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@article{Boudreau1996a,
author = {Boudreau, Bernard P.},
doi = {10.1016/0098-3004(95)00115-8},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Boudreau, A method-of-lines code for carbon and nutrient diagenesis in aquatic sediments, 1996.pdf:pdf},
isbn = {0098-3004},
issn = {00983004},
journal = {Computers and Geosciences},
number = {5},
pages = {479--496},
title = {{A method-of-lines code for carbon and nutrient diagenesis in aquatic sediments}},
volume = {22},
year = {1996}
}
@article{Bick1989a,
abstract = {A polychaete new for the Baltic Sea was recorded during routine sampling in the Darss-Zingst bodden chain (Southern Baltic) in 1985. It was identified as Marenzelleria viridis (Verrill, 1873). Since 1987, the species has been numerous in this estuary, with densities up to 740 ind. X m−2. In April 1988, its expansion into the oligohaline parts of the bodden chain was recorded. The species inhabits sandy and muddy sediments. No relationship between abundance and type of sediment could be found. The most important taxonomic characters of this polychaete are described and figured. 8 scanning electron micrographs complete the diagnosis. An identification key to the 13 spionid polychaetes known from the Baltic Sea is presented.},
author = {Bick, Andreas and Burckhardt, Roger},
doi = {10.1002/mmnz.19890650208},
issn = {18600743},
journal = {Mitteilungen aus dem Museum f{\"{u}}r Naturkunde in Berlin. Zoologisches Museum und Institut f{\"{u}}r Spezielle Zoologie (Berlin)},
keywords = {Baltic Sea,Marenzelleria viridis,Polychaeta,Spionidae,ecology,identification key,redescription},
number = {2},
pages = {237--247},
title = {{Erstnachweis von Marenzelleria viridis (Polychaeta, Spionidae) f{\"{u}}r den Ostseeraum, mit einem Bestimmungsschl{\"{u}}ssel der Spioniden der Ostsee}},
volume = {65},
year = {1989}
}
@article{Egger2016b,
abstract = {Globally, the methane (CH4) efflux from the ocean to the atmosphere is small, despite high rates of CH4 production in continental shelf and slope environments. This low efflux results from the biological removal of CH4 through anaerobic oxidation with sulfate in marine sediments. In some settings, however, pore water CH4 is found throughout the sulfate-bearing zone, indicating an apparently inefficient oxidation barrier for CH4. Here we demonstrate that rapid sediment accumulation can explain this limited capacity for CH4 removal in coastal sediments. In a saline coastal reservoir (Lake Grevelingen, The Netherlands), we observed high diffusive CH4 effluxes from the sediment into the overlying water column (0.2–0.8 molm-2 yr-1) during multiple years. Linear pore water CH4 profiles and the absence of an isotopic enrichment commonly associated with CH4 oxidation in a zone with high rates of sulfate reduction (50–170 nmol cm-3 d-1) both suggest that CH4 is bypassing the zone of sulfate reduction.We propose that the rapid sediment accumulation at this site ({\~{}}13 cm yr-1) reduces the residence time of the CH4 oxidizing microorganisms in the sulfate/methane transition zone ({\textless} 5 years), thus making it difficult for these slow growing methanotrophic communities to build-up sufficient biomass to efficiently remove pore water CH4. In addition, our results indicate that the high input of organic matter ({\~{}} 91 mol Cm-2 yr-1) allows for the co-occurrence of different dissimilatory respiration processes, such as (acetotrophic) methanogenesis and sulfate reduction in the surface sediments by providing abundant sub- strate. We conclude that anthropogenic eutrophication and rapid sediment accumulation likely increase the release of CH4 from coastal sediments.},
author = {Egger, Matthias and Lenstra, Wytze and Jong, Dirk and Meysman, Filip J.R. and Sapart, C{\'{e}}lia J. and {Van Der Veen}, Carina and R{\"{o}}ckmann, Thomas and Gonzalez, Santiago and Slomp, Caroline P.},
doi = {10.1371/journal.pone.0161609},
isbn = {1932-6203},
issn = {19326203},
journal = {PLoS ONE},
number = {8},
title = {{Rapid sediment accumulation results in high methane effluxes from coastal sediments}},
volume = {11},
year = {2016}
}
@article{Reed2011b,
abstract = {A multicomponent diagenetic model was developed and applied to reconstruct the conditions under which the most recent sapropel, S1, was deposited in the eastern Mediterranean Sea. Simulations demonstrate that bottom waters must have been anoxic and sulphidic during the formation of S1 and that organic matter deposition was approximately three times higher than at present. Nevertheless, most present day sediment and pore water profiles - with the exception of pyrite, iron oxyhydroxides, iron-bound phosphorus and phosphate - can be reproduced under a wide range of redox conditions during formation of S1 by varying the depositional flux of organic carbon. As a result, paleoredox indicators (e.g., Corg:S ratio, Corg:Porg ratio, trace metals) are needed when assessing the contribution of oxygen-depletion and enhanced primary production to the formation of organic-rich layers in the geological record. Furthermore, simulations show that the organic carbon concentration in sediments is a direct proxy for export production under anoxic bottom waters. The model is also used to examine the post-depositional alteration of the organic-rich layer focussing on nitrogen, phosphorus, and organic carbon dynamics. After sapropel formation, remineralisation is dominated by aerobic respiration at a rate that is inversely proportional to the time since bottom waters became oxic once again. A sensitivity analysis was undertaken to identify the most pertinent parameters in regulating the oxidation of sapropels, demonstrating that variations in sedimentation rate, depositional flux of organic carbon during sapropel formation, bottom water oxygen concentration, and porosity have the largest impact. Simulations reveal that sedimentary nutrient cycling was markedly different during the formation of S1, as well as after reoxygenation of bottom waters. Accumulation of organic nitrogen in sediments doubled during sapropel deposition, representing a significant nitrogen sink. Following reventilation of deep waters, N2 production by denitrification was almost 12 times greater than present day values. Phosphorus cycling also exhibits a strong redox sensitivity. The benthic efflux of phosphate was up to 3.5 times higher during the formation of S1 than at present due to elevated depositional fluxes of organic matter coupled with enhanced remineralisation of organic phosphorus. Reoxygenation of bottom waters leads to a large phosphate pulse to the water column that declines rapidly with time due to rapid oxidation of organic material. The oxidation of pyrite at the redox front forms iron oxyhydroxides that bind phosphorus and, thus, attenuate the benthic phosphate efflux. These results underscore the contrasting effects of oxygen-depletion on sedimentary nitrogen and phosphorus cycling. The simulations also confirm that the current conceptual paradigm of sapropel formation and oxidation is valid and quantitatively coherent. ?? 2011 Elsevier Ltd.},
author = {Reed, Daniel C. and Slomp, Caroline P. and de Lange, Gert J.},
doi = {10.1016/j.gca.2011.07.002},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/reed, OM reconstruction model 2011.pdf:pdf},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
number = {19},
pages = {5540--5558},
publisher = {Elsevier Ltd},
title = {{A quantitative reconstruction of organic matter and nutrient diagenesis in Mediterranean Sea sediments over the Holocene}},
url = {http://dx.doi.org/10.1016/j.gca.2011.07.002},
volume = {75},
year = {2011}
}
@article{Leipe2011,
author = {Leipe, Thomas and Tauber, Franz and Vallius, Henry and Virtasalo, Joonas and U{\'{s}}cinowicz, Szymon and Kowalski, Nicole and Hille, Sven and Lindgren, Susanna and Myllyvirta, Tero},
issn = {0276-0460},
journal = {Geo-Marine Letters},
number = {3},
pages = {175--188},
publisher = {Springer},
title = {{Particulate organic carbon (POC) in surface sediments of the Baltic Sea}},
volume = {31},
year = {2011}
}
@article{Meysman2006,
abstract = {Bioturbation refers to the biological reworking of soils and sediments, and its importance for soil processes and geomorphology was first realised by Charles Darwin, who devoted his last scientific book to the subject. Here, we review some new insights into the evolutionary and ecological role of bioturbation that would have probably amazed Darwin. In modern ecological theory, bioturbation is now recognised as an archetypal example of 'ecosystem engineering', modifying geochemical gradients, redistributing food resources, viruses, bacteria, resting stages and eggs. From an evolutionary perspective, recent investigations provide evidence that bioturbation had a key role in the evolution of metazoan life at the end of the Precambrian Era. {\textcopyright} 2006 Elsevier Ltd. All rights reserved.},
author = {Meysman, Filip J R and Middelburg, Jack J. and Heip, Carlo H R},
doi = {10.1016/j.tree.2006.08.002},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Meysman, Bioturbation a fresh look at darwins last idea, 2006.pdf:pdf},
isbn = {0169-5347},
issn = {01695347},
journal = {Trends in Ecology and Evolution},
number = {12},
pages = {688--695},
pmid = {16901581},
title = {{Bioturbation: a fresh look at Darwin's last idea}},
volume = {21},
year = {2006}
}
@article{Nembrini1983,
abstract = {The interstitial waters and the solid phase of a core collected in Lago Maggiore (Italy) were analysed principally for Fe and P. Thermodynamic equilibrium calculations from the data of the pore fluids show that the interstitial waters are oversaturated with respect to vivianite in the upper part of the core. "Vivianite" was detected by optical microscopy as brown-orange concretions at depth below 3 cm and as blue concretions below 5.5 cm. At the 7-8 cm level these concretions were sufficiently large to be separated from the sediment and SEM-EDAX analysis showed the blue and the brown-orange concretions to have similar compositions. X-ray diffraction identified the blue concretions as vivianite, which M{\"{o}}ssbauer spectroscopy showed to be partially oxidized. The brown-orange concretions were identified as fully oxidized vivianite. Total P and total Fe profiles in the core together with sedimentation data help to explain the presence of these large concretions at a depth of 7-8 cm. {\textcopyright} 1983.},
author = {Nembrini, G. P. and Capobianco, J. A. and Viel, M. and Williams, A. F.},
doi = {10.1016/0016-7037(83)90304-6},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/nebrini1983.pdf:pdf},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
number = {8},
pages = {1459--1464},
title = {{A M{\"{o}}ssbauer and chemical study of the formation of vivianite in sediments of Lago Maggiore (Italy)}},
volume = {47},
year = {1983}
}
@article{Egger2015a,
abstract = {Studies of authigenic phosphorus (P) minerals in marine sediments typically focus on authigenic carbonate fluorapatite, which is considered to be the major sink for P in marine sediments and can easily be semi-quantitatively extracted with the SEDEX sequential extraction method. The role of other potentially important authigenic P phases, such as the reduced iron (Fe) phosphate mineral vivianite (Fe(II)3(PO4)*8H2O) has so far largely been ignored in marine systems. This is, in part, likely due to the fact that the SEDEX method does not distinguish between vivianite and P associated with Fe-oxides. Here, we show that vivianite can be quantified in marine sediments by combining the SEDEX method with microscopic and spectroscopic techniques such as micro X-ray fluorescence ($\mu$XRF) elemental mapping of resin-embedded sediments, as well as scanning electron microscope-energy dispersive spectroscopy (SEM-EDS) and powder X-ray diffraction (XRD). We further demonstrate that resin embedding of vertically intact sediment sub-cores enables the use of synchrotron-based microanalysis (X-ray absorption near-edge structure (XANES) spectroscopy) to differentiate between different P burial phases in aquatic sediments. Our results reveal that vivianite represents a major burial sink for P below a shallow sulfate/methane transition zone in Bothnian Sea sediments, accounting for 40-50{\%} of total P burial. We further show that anaerobic oxidation of methane (AOM) drives a sink-switching from Fe-oxide bound P to vivianite by driving the release of both phosphate (AOM with sulfate and Fe-oxides) and ferrous Fe (AOM with Fe-oxides) to the pore water allowing supersaturation with respect to vivianite to be reached. The vivianite in the sediment contains significant amounts of manganese ({\~{}}4-8wt.{\%}), similar to vivianite obtained from freshwater sediments. Our results indicate that methane dynamics play a key role in providing conditions that allow for vivianite authigenesis in coastal surface sediments. We suggest that vivianite may act as an important burial sink for P in brackish coastal environments worldwide.},
author = {Egger, Matthias and Jilbert, Tom and Behrends, Thilo and Rivard, Camille and Slomp, Caroline P.},
doi = {10.1016/j.gca.2015.09.012},
file = {:C$\backslash$:/Users/Wytse Lenstra/AppData/Local/Mendeley Ltd./Mendeley Desktop/Downloaded/Egger et al. - 2015 - Vivianite is a major sink for phosphorus in methanogenic coastal surface sediments.pdf:pdf},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
pages = {217--235},
publisher = {Elsevier Ltd},
title = {{Vivianite is a major sink for phosphorus in methanogenic coastal surface sediments}},
url = {http://dx.doi.org/10.1016/j.gca.2015.09.012},
volume = {169},
year = {2015}
}
@article{Beal2009,
abstract = {Anaerobic methanotrophs help regulate Earth's climate and may have been an important part of the microbial ecosystem on the early Earth. The anaerobic oxidation of methane (AOM) is often thought of as a sulfate-dependent process, despite the fact that other electron acceptors are more energetically favorable. Here, we show that microorganisms from marine methane-seep sediment in the Eel River Basin in California are capable of using manganese (birnessite) and iron (ferrihydrite) to oxidize methane, revealing that marine AOM is coupled, either directly or indirectly, to a larger variety of oxidants than previously thought. Large amounts of manganese and iron are provided to oceans from rivers, indicating that manganese- and iron-dependent AOM have the potential to be globally important.},
author = {Beal, Emily J and House, Christopher H and Orphan, Victoria J},
doi = {10.1126/science.1169984},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Proposal papers/Beal, Manganese- and iron-dependent marine (Fe and Methane).pdf:pdf},
isbn = {0036-8075},
issn = {0036-8075},
journal = {Science},
number = {5937},
pages = {184--187},
pmid = {19589998},
title = {{Manganese- and iron-dependent marine methane oxidation.}},
volume = {325},
year = {2009}
}
@article{Asmala2017,
abstract = {Despite slow nutrient supply to the subtropical surface ocean, the rates of annual inorganic carbon uptake and net oxygen production are similar to those of nutrient-rich high-latitude waters. This surprisingly high subtropical carbon uptake cannot be fully accounted for by sediment trap-collected sinking particles and the downward mixing of suspended and dissolved organic carbon. We propose an explanation for these paradoxical observations: gel-like organic matter rich in carbon but poor in nutrients, akin to transparent exopolymer particles, is produced by phytoplankton under nutrient limitation, and a portion sinks into the shallow subsurface, where it is respired by heterotrophic bacteria. This organic matter would evade detection by sediment traps, effectively representing an additional (sinking-driven) source of dissolved organic carbon to the subsurface. Building on existing evidence for the production of such nutrient-poor organic matter in surface waters, we describe evidence for its decomposition in the shallow subsurface of the Sargasso Sea. First, oxygen at these depths is consumed over the summer without comparable production of nitrate. Second, a seasonal change in the},
author = {Asmala, Eero and Carstensen, Jacob and Conley, Daniel and Slomp, Caroline P. and Stadmark, J and Voss, Maren},
doi = {10.13140/RG.2.1.3702.8566},
isbn = {7034894671},
issn = {09088857},
journal = {Limnology and Oceanography},
title = {{Efficiency of the coastal filter: nitrogen and phosphorous removal in the Baltic Sea}},
year = {2017}
}
@article{Egger2017,
abstract = {Methane is a powerful greenhouse gas and its emission from marine sediments to the atmosphere is largely controlled by anaerobic oxidation of methane (AOM). Traditionally, sulfate is considered to be the most important electron acceptor for AOM in marine sediments. Recent evidence suggests, however, that AOM may also be coupled to the reduction of iron (Fe) oxides. In the Baltic Sea, the post-glacial transition from the Ancylus freshwater phase to the Littorina brackish/marine phase (A/L-transition) around 9–7 kyr BP (before present), resulted in the accumulation of organic-rich brackish/marine sediments overlying organic-poor limnic deposits rich in Fe oxides. Methane produced in the organic-rich layer diffuses into the lake sediments, thus allowing for the possible coupling between Fe oxide reduction and methane oxidation. Here, we combine detailed geochemical analyses of the sediment and pore water retrieved from three sites that were drilled during the IODP Baltic Sea Paleoenvironment Expedition 347 with multicomponent diagenetic modeling to study the possible role of Fe-mediated AOM as a mechanism for the apparent Fe oxide reduction in the methane-bearing lake deposits below the A/L transition. Our results reveal a complex interplay between production, oxidation and transport of methane showing that besides organoclastic Fe reduction, oxidation of downward migrating methane with Fe oxides may also explain the elevated concentrations of dissolved ferrous Fe in deep Baltic Sea sediments. Our findings imply that the transition of a lake toward a marine system could lead to reactivation of deeply buried, mostly crystalline Fe oxides in organic-poor lake deposits through reactions with downward diffusing methane from the overlying organic-rich marine sediments. Based on the geochemical profiles and numerical modeling, we propose that a potential coupling between Fe oxide reduction and methane oxidation likely affects deep Fe cycling and related biogeochemical processes, such as burial of phosphorus, in systems subject to changes in organic matter loading or bottom water salinity.},
author = {Egger, Matthias and Hagens, Mathilde and Sapart, C{\'{e}}lia J. and Dijkstra, Nikki and van Helmond, Niels A.G.M. and Mogoll{\'{o}}n, Jos{\'{e}} M. and Risgaard-Petersen, Nils and van der Veen, Carina and Kasten, Sabine and Riedinger, Natascha and B{\"{o}}ttcher, Michael E. and R{\"{o}}ckmann, Thomas and J{\o}rgensen, Bo Barker and Slomp, Caroline P.},
doi = {10.1016/j.gca.2017.03.019},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
keywords = {Baltic Sea,Iron reduction,Marine sediments,Methane},
pages = {256--276},
title = {{Iron oxide reduction in methane-rich deep Baltic Sea sediments}},
volume = {207},
year = {2017}
}
@article{Rember2004,
abstract = {Arctic rivers typically transport more than half of their annual amounts of water and suspended sediments during spring floods. In this study, the Sagavanirktok, Kuparuk and Colville rivers in the Alaskan Arctic were sampled during the spring floods of 2001 to determine levels of total suspended solids (TSS) and dissolved and particulate metals and organic carbon. Concentrations of dissolved organic carbon (DOC) increased from 167 to 742 ??mol/L during peak discharge in the Sagavanirktok River, at about the same time that river flow increased to maximum levels. Concentrations of dissolved Cu, Pb, Zn and Fe in the Sagavanirktok River followed trends observed for DOC with 3- to 25-fold higher levels at peak flow than during off-peak discharge. Similar patterns were found for the Kuparuk and Colville rivers, where average concentrations of dissolved trace metals and DOC were even higher. These observations are linked to a large pulse of DOC and dissolved metals incorporated into snowmelt from thawing ponds and upper soil layers. In contrast with Cu, Fe, Pb and Zn, concentrations of dissolved Ba did not increase in response to increased discharge of water, TSS and DOC. Concentrations of particulate Cu, Fe, Pb and Zn were more uniform than observed for their respective dissolved species and correlated well with the Al content of the suspended particles. However, concentrations of particulate Al were poorly correlated with particulate organic carbon. Results from this study show that {\textgreater}80{\%} of the suspended sediment and more than one-third of the annual inputs of dissolved Cu, Fe, Pb, Zn and DOC were carried to the coastal Beaufort Sea in 3 and 12 d, respectively, by the Kuparuk and Sagavanirktok rivers. ?? 2004 Elsevier Ltd.},
author = {Rember, Robert D. and Trefry, John H.},
doi = {10.1016/S0016-7037(03)00458-7},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
number = {3},
pages = {477--489},
title = {{Increased concentrations of dissolved trace metals and organic carbon during snowmelt in rivers of the Alaskan Arctic}},
volume = {68},
year = {2004}
}
@article{Meier2012,
abstract = {Multi-model ensemble simulations for the marine biogeochemistry and food web of the Baltic Sea were performed for the period 1850–2098, and projected changes in the future climate were compared with the past climate environment. For the past period 1850–2006, atmospheric, hydrological and nutrient forcings were reconstructed, based on historical measurements. For the future period 1961–2098, scenario simulations were driven by regionalized global general circulation model (GCM) data and forced by various future greenhouse gas emission and air- and riverborne nutrient load scenarios (ranging from a pessimistic ‘business-as-usual' to the most optimistic case). To estimate uncertainties, different models for the various parts of the Earth system were applied. Assuming the IPCC greenhouse gas emission scenarios A1B or A2, we found that water temperatures at the end of this century may be higher and salinities and oxygen concentrations may be lower than ever measured since 1850. There is also a tendency of increased eutrophication in the future, depending on the nutrient load scenario. Although cod biomass is mainly controlled by fishing mortality, climate change together with eutrophication may result in a biomass decline during the latter part of this century, even when combined with lower fishing pressure. Despite considerable shortcomings of state-of-the-art models, this study suggests that the future Baltic Sea ecosystem may unprecedentedly change compared to the past 150 yr. As stakeholders today pay only little attention to adaptation and mitigation strategies, more information is needed to raise public awareness of the possible impacts of climate change on marine ecosystems.},
author = {Meier, H E Markus and Andersson, Hel{\'{e}}n C and Arheimer, Berit and Blenckner, Thorsten and Chubarenko, Boris and Donnelly, Chantal and Eilola, Kari and Gustafsson, Bo G and Hansson, Anders and Havenhand, Jonathan and H{\"{o}}glund, Anders and Kuznetsov, Ivan and MacKenzie, Brian R and M{\"{u}}ller-Karulis, B{\"{a}}rbel and Neumann, Thomas and Niiranen, Susa and Piwowarczyk, Joanna and Raudsepp, Urmas and Reckermann, Marcus and Ruoho-Airola, Tuija and Savchuk, Oleg P and Schenk, Frederik and Schimanke, Semjon and V{\"{a}}li, Germo and Weslawski, Jan-Marcin and Zorita, Eduardo},
doi = {10.1088/1748-9326/7/3/034005},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Meier 2012 future projections baltic.pdf:pdf},
isbn = {1748-9326},
issn = {1748-9326},
journal = {Environmental Research Letters},
number = {3},
pages = {034005},
title = {{Comparing reconstructed past variations and future projections of the Baltic Sea ecosystem—first results from multi-model ensemble simulations}},
volume = {7},
year = {2012}
}
@article{Fleming-Lehtinen2012,
abstract = {Secchi depth, as a proxy of water transparency, provides valuable information on the availability of light to the underwater ecosystems. Changes in water transparency have also been widely linked to eutrophication and phytoplankton biomass. This study aimed to describe the development of water transparency in the Baltic Sea through a unique century-long set of Secchi depth observations. Furthermore, the aim was to explain the role of phytoplankton in determining water transparency in these optically complex waters. Water transparency in the open Baltic Sea has decreased during the last one hundred years. The development differs between the sub-basins of the Baltic Sea. The decrease has been most profound in the north-eastern Baltic sub-basins, but apparent also in parts of the Southern and Central Baltic. In many of the northern areas the decrease has accelerated during the last decades, whereas in the Southern Baltic a recent increase was observed. The analysis of simultaneous chlorophyll . a observations during the period from 1972 to 2006 revealed that during summer time, 13-17{\%} of the light attenuation can be attributed to phytoplankton. In spring, the average proportion is between 31 and 42{\%}, with great variation between observations. We find Secchi depth a suitable indicator of eutrophication, integrating various organic matter related features. It should always be applied with sufficient background information of the optical properties of the water mass, and complemented by other indicators. ?? 2012 Elsevier Ltd.},
author = {Fleming-Lehtinen, Vivi and Laamanen, Maria},
doi = {10.1016/j.ecss.2012.02.015},
isbn = {0272-7714},
issn = {02727714},
journal = {Estuarine, Coastal and Shelf Science},
keywords = {Baltic Sea,Chlorophyll a,Eutrophication,Secchi depth},
pages = {1--10},
title = {{Long-term changes in Secchi depth and the role of phytoplankton in explaining light attenuation in the Baltic Sea}},
volume = {102-103},
year = {2012}
}
@misc{Alpha1967,
author = {Clesceri, LenoreS. and Greenberg, Arnold E. and Eaton, Andrew D.},
booktitle = {Health laboratory science},
doi = {10.2105/AJPH.51.6.940-a},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/alpha, measuring methods,.pdf:pdf},
isbn = {0875530478},
issn = {0017-9035},
keywords = {Laboratories,Public Health,United States,Water Pollution,Water Supply},
pages = {137--41},
pmid = {6033010},
title = {{Standard methods for the examination of water and wastewater.}},
url = {http://www.ncbi.nlm.nih.gov/pubmed/17489283},
volume = {4},
year = {1967}
}
@article{Slomp1996b,
abstract = {Differential X-ray powder diffraction (DXRD) and extraction procedures were used to characterize the iron oxides present in four sediments from contrasting environments in the North Sea. Stations were located in depositional areas on the southern shelf (German Bight) and on the north-eastern shelf-slope transition (Skagerrak) and in areas with no net deposition in the southern North Sea. Poorly crystalline ferrihydrite and akageneite (extractable with 0.1 M HCI and 0.2 M NH4-oxalate) were identified in the fine sediment fraction ({\textless} 10 $\mu$m) of surface samples at all locations. Evidence for the dominant role of these Fe oxides in the binding of phosphorus in North Sea sediments was obtained from the good relationship of both the content of Fe-bound P and the linear adsorption coefficient for phosphate with NH4-oxalate extractable Fe. A tight coupling of pore water Fe2+ and HPO42− was observed at 3 stations. Pore water View the MathML source ratios at maximum pore water concentrations of Fe2+ were similar to NH4-oxalate View the MathML source P ratios for surface sediment at these locations, and were in the range known for synthetic poorly crystalline Fe oxides. This suggests that pore water HPO42− production at the time of core collection was dominated by release from poorly crystalline Fe oxides. In contrast, at the German Bight station, much higher HPO42− levels and a decoupling of pore water Fe2+ and HPO42− was observed, suggesting a larger contribution of mineralization of organic matter to pore water HPO42− than at the other sites. Solid phase P analyses indicate possible redistribution of Fe-bound P to another inorganic phase at depth at the Skagerrak station, but not at the other stations. The persistence with depth of poorly crystalline Fe oxides and Fe-bound P suggests that these Fe phases can act as both a temporary and permanent sink for P in continental margin sediments.},
author = {Slomp, C.P. and {Van der Gaast}, S.J. and {Van Raaphorst}, W.},
doi = {10.1016/0304-4203(95)00078-X},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Slomp, phosphorus binding by poorlu crystalline iron oxides in North Sea sediments, 1996.pdf:pdf},
isbn = {0304-4203},
issn = {03044203},
journal = {Marine Chemistry},
number = {1},
pages = {55--73},
title = {{Phosphorus binding by poorly crystalline iron oxides in North Sea sediments}},
volume = {52},
year = {1996}
}
@article{Nriagu1972a,
abstract = {A portion of the solubility isotherm for synthetic vivianite (Fe3(PO4)2{\textperiodcentered}8H2O) in the three component system Fe3(PO4)2-H3PO4-H2O has been determined at 25°C. Interpretation of the data allowing for the formation of the ion-pairs FeH2PO4+ and FeHPO4° resulted in the solubility product constant for vivianite of 10-36.0±0.1. The association constants obtained were 102.7±0.2 and 103.6±0.3 respectively for FeH2PO4+ and FeHPO4°. The solubility data show that vivianite may be of significance in controlling the phosphate concentration in anaerobic sedimentary environments and that Fe2+ can be an effective precipitant for removing orthophosphates from anaerobic digester supernatant and related process streams. The $\Delta$Gf° for vivianite of -1037 kcal/mole along with the other data from the literature were used to construct diagrams depicting the stability fields of vivianite and strengite (FePO4{\textperiodcentered}2H2O) in different chemical environments. {\textcopyright} 1972.},
author = {Nriagu, Jerome O.},
doi = {10.1016/0016-7037(72)90035-X},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
number = {4},
pages = {459--470},
title = {{Stability of vivianite and ion-pair formation in the system Fe3(PO4)2-H3PO4H3PO4-H2O}},
volume = {36},
year = {1972}
}
@article{Norkko2012,
abstract = {Invasive species and bottom-water hypoxia both constitute major global threats to the diversity and integrity of marine ecosystems. These stressors may interact with unexpected consequences, as invasive species that require an initial environmental disturbance to become established can subsequently become important drivers of ecological change. There is recent evidence that improved bottom-water oxygen conditions in coastal areas of the northern Baltic Sea coincide with increased abundances of the invasive polychaetes Marenzelleria spp. Using a reactive-transport model, we demonstrate that the long-term bioirrigation activities of dense Marenzelleria populations have a major impact on sedimentary phosphorus dynamics. This may facilitate the switch from a seasonally hypoxic system back to a normoxic system by reducing the potential for sediment-induced eutrophication in the upper water column. In contrast to short-term laboratory experiments, our simulations, which cover a 10-year period, show that Marenzelleria has the potential to enhance long-term phosphorus retention in muddy sediments. Over time bioirrigation leads to a substantial increase in the iron-bound phosphorus content of sediments while reducing the concentration of labile organic carbon. As surface sediments are maintained oxic, iron oxyhydroxides are able to persist and age into more refractory forms. The model illustrates mechanisms through which Marenzelleria can act as a driver of ecological change, although hypoxic disturbance or natural population declines in native species may be needed for them to initially become established. Invasive species are generally considered to have a negative impact; however, we show here that one of the main recent invaders in the Baltic Sea may provide important ecosystem services. This may be of particular importance in low-diversity systems, where disturbances may dramatically alter ecosystem services due to low functional redundancy. Thus, an environmental problem in one region may be either exacerbated or alleviated by a single species from another region, with potentially ecosystem-wide consequences.},
author = {Norkko, Joanna and Reed, Daniel C. and Timmermann, Karen and Norkko, Alf and Gustafsson, Bo G. and Bonsdorff, Erik and Slomp, Caroline P. and Carstensen, Jacob and Conley, Daniel J.},
doi = {10.1111/j.1365-2486.2011.02513.x},
file = {:C$\backslash$:/Users/Wytse Lenstra/AppData/Local/Mendeley Ltd./Mendeley Desktop/Downloaded/Norkko et al. - 2012 - A welcome can of worms Hypoxia mitigation by an invasive species.pdf:pdf},
isbn = {1365-2486},
issn = {13541013},
journal = {Global Change Biology},
keywords = {Hypoxia,Invasive species,Multiple stressors,Reactive-transport model,Remediation,Sediment phosphorus dynamics},
number = {2},
pages = {422--434},
title = {{A welcome can of worms? Hypoxia mitigation by an invasive species}},
volume = {18},
year = {2012}
}
@article{Mortimer1941,
author = {Society, British Ecological},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Mortimer, The Exchange of Dissolved Substances Between Mud and Water in Lakes, 1941.pdf:pdf},
journal = {Society},
number = {2},
pages = {280--329},
title = {{The Exchange of Dissolved Substances Between Mud and Water in Lakes Author ( s ): Clifford H . Mortimer Published by : British Ecological Society Stable URL : http://www.jstor.org/stable/2256395}},
volume = {29},
year = {2010}
}
@incollection{Wulff2001,
author = {Wulff, F and Rahm, L and Hallin, A.K. and Sandberg, J},
booktitle = {A Systems Analysis of the Baltic Sea},
doi = {10.1007/978-3-662-04453-7-13},
isbn = {978-3-662-04453-7},
pages = {353--372},
title = {{A Nutrient Budget Model of the Baltic Sea}},
url = {http://dx.doi.org/10.1007/978-3-662-04453-7-13},
year = {2001}
}
@article{Egger2015b,
abstract = {Methane is a powerful greenhouse gas and its biological conversion in marine sediments, largely controlled by anaerobic oxidation of methane (AOM), is a crucial part of the global carbon cycle. However, little is known about the role of iron oxides as an oxidant for AOM. Here we provide the first field evidence for iron-dependent AOM in brackish coastal surface sediments and show that methane produced in Bothnian Sea sediments is oxidized in distinct zones of iron- and sulfate-dependent AOM. At our study site, anthropogenic eutrophication over recent decades has led to an upward migration of the sulfate/methane transition zone in the sediment. Abundant iron oxides and high dissolved ferrous iron indicate iron reduction in the methanogenic sediments below the newly established sulfate/methane transition. Laboratory incubation studies of these sediments strongly suggest that the in situ microbial community is capable of linking methane oxidation to iron oxide reduction. Eutrophication of coastal environments may therefore create geochemical conditions favorable for iron-mediated AOM and thus increase the relevance of iron-dependent methane oxidation in the future. Besides its role in mitigating methane emissions, iron-dependent AOM strongly impacts sedimentary iron cycling and related biogeochemical processes through the reduction of large quantities of iron oxides.},
author = {Egger, Matthias and Rasigraf, Olivia and Sapart, C{\'{e}}lia J. and Jilbert, Tom and Jetten, Mike S M and R{\"{o}}ckmann, Thomas and {Van Der Veen}, Carina and B{\^{a}}nda, Narcisa and Kartal, Boran and Ettwig, Katharina F. and Slomp, Caroline P.},
doi = {10.1021/es503663z},
isbn = {1520-5851 (Electronic)$\backslash$r0013-936X (Linking)},
issn = {15205851},
journal = {Environmental Science and Technology},
number = {1},
pages = {277--283},
pmid = {25412274},
title = {{Iron-mediated anaerobic oxidation of methane in brackish coastal sediments}},
volume = {49},
year = {2015}
}
@article{Soetaert2010,
author = {Soetaert, Karline and Petzoldt, Thomas and Meysman, Filip J. R.},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Soetaert, marelac, 2010.pdf:pdf},
journal = {R package},
keywords = {coastal science,constants,estuarine,lacustrine,marine,r,riverine,utilities},
title = {{Marelac: Tools for Aquatic Sciences v2.1.3}},
year = {2010}
}
@article{Cline1969,
archivePrefix = {arXiv},
arxivId = {98105},
author = {Cline, Joel D.},
doi = {10.4319/lo.1969.14.3.0454},
eprint = {98105},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Cline, sulfide measure method.pdf:pdf},
isbn = {1939-5590},
issn = {00243590},
journal = {Limnology and Oceanography},
number = {3},
pages = {454--458},
title = {{Spectrophotometric determination of hydrogen sulfide in natural waters}},
volume = {14},
year = {1969}
}
@article{Berg2003,
abstract = {In this paper, we present a dynamic diagenetic model of the oxygen consumption pathways and cycling of carbon, nitrogen, manganese, iron, and sulfur in marine sediments. Sixteen dissolved or solid species are included in our model and the vertical transport processes accounted for are molecular diffusion, bioturbation, irrigation, and burial. Adsorption of dissolved species onto solid sediment is assumed to be reversible and to follow a linear equilibrium isotherm. Interactions between species are formulated in 21 biogeochemical reactions that are regulated through simplified Michaelis-Menten kinetics. The key driving input parameter to the model is the transient flux of organic matter supplied to the sediment surface, below which mineralization is described through the well-known 3-G model that includes a fast, a slow, and a non-degradable pool of organic matter. The model was applied to the Arctic sediment of Young Sound in Northeast Greenland using extensive measurements covering a full annual cycle. The model parameterization was performed in a stepwise process, first focusing on parameters describing transport in the sediment and then on parameters related to biogeochemical reactions. The model successfully simulated the measured concentration-depth profiles of O-2, SigmaCO(2), NH4+, NO3-, Mn2+, Fe2+, adsorbed Fe2+ SO4+ H2S FeS2, FeS2, MnO2, FeOOH, and organic matter; sediment-water fluxes of SigmaCO(2), O-2, NH4+, and NO3- ; depth-integrated process rates of denitrification and sulfate reduction; and depth profiles of iron-and sulfate reduction rates. The model application to the Young Sound sediment provided an excellent means to examine whether our perceptions of the most significant transport processes and biogeochemical reactions were correct. The successful simulation of measured data supported their internal consistency and confirmed previously reported interpretations and conclusions. The imposed supply of organic matter to the sediment surface that reproduced the measured data was found to be almost three times higher for the month of July than the average for the rest of the year. The peak in organic matter supply in mid-July coincided with the disappearance of sea ice. A sensitivity analysis performed for the model showed that the rate constants for the two degradable pools of organic matter were among those input variables that most affected the simulated results. As a result, we are confident of the accuracy of these rate constants of 76 y(-1) and 0.095 y(-1). In comparison with results from temperate sediments, these constants showed no significant correlation to the sub-zero Arctic temperatures. The reproduction of measured data for the sulfur cycle could be obtained only when sulfur disproportionation was included in the model as a sink for S-0, indicating that this process plays an important role in the Young Sound sediment.},
author = {Berg, P and Rysgaard, S and Thamdrup, B},
doi = {10.2475/ajs.303.10.905},
isbn = {0002-9599},
issn = {00029599},
journal = {American Journal of Science},
keywords = {aquatic sediments,bacterial sulfate reduction,continental-margin sediments,elemental sulfur,long-island sound,organic-matter,quantifying bioirrigation,reactive transport,surface sediments,young sound},
number = {10},
pages = {905--955},
pmid = {46},
title = {{Dynamic modeling of early diagenesis and nutrient cycling. A case study in an Arctic marine sediment}},
volume = {303},
year = {2003}
}
@article{Algesten2006,
abstract = {We calculated input of organic carbon to the unproductive, brackish water basin of the Gulf of Bothnia from rivers, point sources and the atmosphere. We also calculated the net exchange of organic carbon between the Gulf of Bothnia and the adjacent marine system, the Baltic Proper. We compared the input with sinks for organic carbon; permanent incorporation in sediments and mineralization and subsequent evasion of CO2 to the atmosphere. The major fluxes were riverine input (1500??Gg C year- 1), exchange with the Baltic Proper (depending on which of several possible DOC concentration differences between the basins that was used in the calculation, the flux varied between an outflow of 466 and an input of 950??Gg C year- 1), sediment burial (1100??Gg C year- 1) and evasion to the atmosphere (3610??Gg C year- 1). The largest single net flux was the emission of CO2 to the atmosphere, mainly caused by bacterial mineralization of organic carbon. Input and output did not match in our budget which we ascribe uncertainties in the calculation of the exchange of organic carbon between the Gulf of Bothnia and the Baltic Proper, and the fact that CO2 emission, which in our calculation represented 1??year (2002) may have been overestimated in comparison with long-term means. We conclude that net heterotrophy of the Gulf of Bothnia was due to input of organic carbon from both the catchment and from the Baltic Proper and that the future degree of net heterotrophy will be sensible to both catchment export of organic carbon and to the ongoing eutrophication of the Baltic Proper. ?? 2006 Elsevier B.V. All rights reserved.},
author = {Algesten, Grete and Brydsten, Lars and Jonsson, Per and Kortelainen, Pirkko and L{\"{o}}fgren, Stefan and Rahm, Lars and R{\"{a}}ike, Antti and Sobek, Sebastian and Tranvik, Lars and Wikner, Johan and Jansson, Mats},
doi = {10.1016/j.jmarsys.2006.06.004},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Algesten, Organic carbon budget for the Gulf of Bothnia, 2006.pdf:pdf},
isbn = {0924-7963},
issn = {09247963},
journal = {Journal of Marine Systems},
keywords = {Advective flux,CO2 emission,Organic carbon,River transport,Sediment},
number = {3-4},
pages = {155--161},
title = {{Organic carbon budget for the Gulf of Bothnia}},
volume = {63},
year = {2006}
}
@article{Gledhill1994,
abstract = {A method is presented to determine the extent of iron complexation by natural organic ligands in seawater. Catalytic cathodic stripping voltammetry (CSV) is used to take advantage of ligand competition between the added ligand, 1-nitroso-2-napthol (NN), and natural ligands present in seawater. The conditional stability constant for the complexation of iron by NN was calibrated for salinities between 1 and 36 using ligand competition with EDTA. The values of log K′Fe(NN)3 (valid for pH 6.9 seawater) were found to vary linearly with log salinity according to log K′Fe(NN)3 = -1.04 ± 0.08 log(salinity) + 30.12 ± 0.09. The detection window, defined by the iron complexing ability of NN was altered by varying the concentration of NN. Preliminary measurements of iron complexing ligands in samples from coastal and open oceanic origin revealed the presence of natural complexing ligands at concentrations higher than that of total dissolved iron. The stability constants for the complexes were high, log K′FeL falling within the range of 18.8-21.2, indicating that by far the greatest component (99{\%}) of the dissolved iron occurs organically complexed in pH 6.9 seawater. Model calculations showed that it is possible that the organic fraction may be somewhat less at a pH value near 8. {\textcopyright} 1994.},
author = {Gledhill, Martha and van den Berg, Constant M G},
doi = {10.1016/0304-4203(94)90012-4},
isbn = {0304-4203},
issn = {03044203},
journal = {Marine Chemistry},
number = {1},
pages = {41--54},
pmid = {3632535},
title = {{Determination of complexation of iron(III) with natural organic complexing ligands in seawater using cathodic stripping voltammetry}},
volume = {47},
year = {1994}
}
@article{Burton2006,
abstract = {This study describes iron and sulfur fractionation, and the related extractability of selected trace elements (As, Cd, Cr, Cu, Ni, Pb and Zn) in estuarine sediments. The sediments were sulfidic, with moderately high concentrations of pore-water sulfide (200-600 $\mu$mol l-1) and acid-volatile sulfide (AVS; 9.9-129 $\mu$mol g-1). Pyrite-S concentrations increased with depth, with 63-251 $\mu$mol g-1at site W1 and 312-669 $\mu$mol g-1at site W2. The degree of sulfidisation was generally high ({\textgreater}80{\%}), indicating that Fe may be limiting pyrite accumulation. The ratios of AVS to pyrite-S increased with sediment depth, as expected for the pyritisation of solid-phase AVS. Cadmium, Pb and Zn extractability in 1 M HCl indicated that these elements are not significantly sequestered during pyritisation, whereas sequestration may be important for As, Cu and possibly Ni. Extractability trends for Cr suggest that diagenesis in sulfidic sediments may enhance Cr reactivity. Overall, replacement of AVS by pyrite during diagenesis may enhance the reactivity of Cd, Cr, Pb and Zn, whereas As, Cu and possibly Ni may be rendered less reactive. {\textcopyright} 2005 Elsevier Ltd. All rights reserved.},
author = {Burton, Edward D. and Bush, Richard T. and Sullivan, Leigh A.},
doi = {10.1016/j.chemosphere.2005.12.003},
isbn = {0045-6535},
issn = {00456535},
journal = {Chemosphere},
keywords = {AVS,Diagenesis,Heavy metals,Pyrite},
number = {8},
pages = {1421--1428},
pmid = {16434078},
title = {{Fractionation and extractability of sulfur, iron and trace elements in sulfidic sediments}},
volume = {64},
year = {2006}
}
@article{Meysman2005,
abstract = {Current bioturbation models are marked by confusion in their treatment of porosity. Different equations appear to be needed for different biodiffusion mechanisms, i.e., interphase mixing, where biological activity causes bulk mixing of sediment affecting both tracer and porosity profiles, versus intraphase mixing, where the solid components are intermixed, but the porosity is left unchanged. Another issue is whether the model depends upon the particle type with which tracers are associated, e.g., 137Cs on small clay particles versus 210Pb on larger grains. This uncertainty has lead to conflicting conservation equations for radiotracers, and in particular, to the question whether the porosity should be placed inside or outside of the differential term that governs the biodiffusive flux. We have reexamined this situation in the context of multiphase, multicomponent continuum theory. Most importantly, we prove that under the assumption of steady-state porosity, there exists only one correct form of the steady-state conservation equation for a radiotracer, regardless of biodiffusion mechanism and particle type, i.e., ∂/∂x [$\phi$sDB ∂Cs/ ∂x] - Fseds/$\rho$s ∂Cs/∂x - $\phi$s$\lambda$Cs = 0 where x is depth, Cs is the concentration/activity of the tracer, Fseds is the constant flux of solid sediment to the sediment, $\rho$s is the density of the solid phase, $\phi$s is the solid volume fraction, DB is the biodiffusion coefficient, and $\lambda$ is the decay constant. This pertinent finding results from a substantial revision and extension of diagenetic theory. By considering the conservation of momentum, as well as mass, we have identified the correct reference velocities to define biodiffusional fluxes. From that, we have formulated a consistent set of model equations that govern (1) transient porosity and transient tracer concentrations, (2) steady-state porosity and transient tracer concentrations, and (3) steady-state porosity and steady-state tracer concentrations, in sediments that are subject to both compaction and bioturbation. Copyright {\textcopyright} 2005 Elsevier Ltd.},
author = {Meysman, Filip J R and Boudreau, Bernard P. and Middelburg, Jack J.},
doi = {10.1016/j.gca.2005.01.004},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Meysman, Modeling reactive transport in sediments subject to bioturbation and compaction, 2005.pdf:pdf},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
number = {14},
pages = {3601--3617},
title = {{Modeling reactive transport in sediments subject to bioturbation and compaction}},
volume = {69},
year = {2005}
}
@article{Gachter1988,
abstract = {Cycling of phosphorus at the sediment-water interface is traditionally considered to be controlled by pH- and redox-dependent, abiotic processes, such as formation and dissolution of FeOOH-PO4 complexes. In this study, however, a large part of total P in sediments of Lake Sempach, an 87-m deep eutrophic lake, was estimated to be incorporated in bacterial biomass. Laboratory experiments indicated that sediment microorganisms can rapidly take up and release soluble reactive P (SRP), depending on redox conditions, and that sterilization of oxic sediments decreased their SRP sorption capacity. In an in situ experiment conducted in the lake, bacteria also contributed considerably to SRP fixation when water enclosed within a sediment flux chamber was reoxygenated following anoxia. Moreover, in that experiment and in data sets from several other lakes, anoxic releases of Fe and P from sediments appeared to be partly uncoupled. As part of an ongoing revision of the classical model for P exchange across the sediment-water interface, these results provide direct evidence that fixation and release of SRP may be controlled partly by redox-dependent changes in microbial physiology, as well as by production and decomposition of microbial biomass.},
author = {G{\"{a}}chter, Ren{\'{e}} and Meyer, Joseph S. and Mares, Antonin},
isbn = {0024-3590},
issn = {00243590},
journal = {Limnology and Oceanography},
number = {6 part 2},
pages = {1542--1558},
title = {{Contribution of bacteria to release and fixation of phosphorus in lake sediments}},
url = {http://onlinelibrary.wiley.com/doi/10.4319/lo.1988.33.6part2.1542/abstract},
volume = {33},
year = {1988}
}
@article{Nriagu1974,
abstract = {Thermochemical data for many basic iron phosphates have been estimated by a method which regards these cornpounds as components on joins between the simple phosphates and hydroxides. The data so derived have been used to develop models depicting the phase com- patibilities and the general diagenetic behavior of iron phosphates in subaqueous freshwater environments. The models are combined with measurements on the interstitial waters of Lake Erie to define the chemical requirements for the formation of vivianite and other iron phocphates in the Great Lakes sediments. In aerobic lake sediments, ferrosoferric (and manganousferric) hydroxyphosphates are the stable minerals which may be derived by phosphating ferromanganese oxides or by the oxidation of ferrous phosphates. Strengite and simple ferric phosphates are unlikely to be important diagenetic constituents of freshwater sediments. The stable and most probable phosphate minerals in reducing environments are vivianite, reddingite, and anapaite. The precipitation and dissolution of these iron phosphates (particularly vivianite and ludlamite, the dominant phases) in the Great Lakes sedirnents are considered an important buffer mechanism which regulates both the levels of phosphorus in the interstitial waters and the release of phosphorus to the overlying lake waters.},
author = {Nriagu, J.O. and Dell, C.I.},
journal = {American Mineralogist},
keywords = {2-sediment,4-iron,6-Canada,6-Lake Erie,6-Laurentian Great Lakes,6-Ontario},
pages = {934--946},
title = {{Diagenetic Formation of lron Phosphates in Recent Lake Sediments}},
volume = {59},
year = {1974}
}
@article{Jorgensen1978,
abstract = {A mathematical model describing vertical sulfate gradients as a function of diffusion, bacterial reduction, and sedimentation is applied to calculate the steady‐state rates of sulfate reduction in coastal sediments. Diffusion coefficients of sulfate are determined experimentally in different sediment types and depths. The rate of sulfate reduction is also determined directly on sediment cores by a radiotracer technique. Experimentally determined rates are compared with those calculated from the model. The results of the model are shown to depend strongly on its assumptions about the kinetics of bacterial sulfate reduction.},
author = {J{\o}rgensen, B. B.},
doi = {10.1080/01490457809377723},
isbn = {0149-0451},
issn = {0149-0451},
journal = {Geomicrobiology Journal},
number = {1},
pages = {49--64},
title = {{A comparison of methods for the quantification of bacterial sulfate reduction in coastal marine sediments}},
volume = {1},
year = {1978}
}
@article{Nurnberg1984a,
abstract = {Importance of Internal Phosphorus Load to the Eutrophication of Lakes with Anoxic Hypolimnia Nurnberg, G Peters, RH Verhandlung Internationale Vereinigung Limnologie Vol. 22, No. 1, p 190-194, July, 1984. 8 Fig, 9 Ref.},
author = {N{\"{u}}rnberg, Gertrud and Peters, Robert H.},
journal = {Verh. Internat. Verein. Limnol},
number = {1},
pages = {190--194},
title = {{The importance of internal phosphorus load to the eutrophication of lakes with anoxi hypolimnia}},
volume = {22},
year = {1984}
}
@article{VanSantvoort2002,
abstract = {Aerobic mineralisation of Corg in surface sedimentsof the deep ({\textgreater}2000 m water depth) eastern Mediterranean Sea has been quantified by analysis of detailedbox core Corg concentration versus depth profiles and the modelling environment for early diageneticproblems MEDIA. The reactive fraction comprises 60–80{\%} of the total Corg reachingthe sediments and is largely oxidised within the surficial 10 cm. A non-reactive C orgfraction (GNR) dominates at depths {\textgreater}10 cm, and makes up20–40{\%} of the total C org flux to the sediments. First-order rateconstants for decomposition of the reactive fraction calculated from theC org profiles range from 5.4 × 10-3 to8.0 × 10-3 y-1 to 8.0 × 10-3 y-1. Total mineralization rates in thesurface sediment are between 1.7 and 2.6 mol C cm-2 y-1 and thus are typical for oligotrophic, deep-seaenvironments. The low fluxes and rapid remineralisation of C org are accompanied by210Pbexcess surface mixed layers which are only 2 cm deep, among the thinnest reported for oxygenated marine sediments.Model results indicate a mismatch between the C org profiles and O2 microprofileswhich were measured onboard ship. This can be attributed to a combination of decompression artefactsaffecting onboard measurement of the O2 profiles or the leakage ofoxygen into the core during handling on deck. Furthermore, the used Db values, based on 210Pb, may not befully appropriate; calculations with higher Db values improve the O2 fits. The surficial sediment13C org values of  -22 become less negative with increasing depth and decreasing C orgconcentrations. The major 13C change occurs in the top 3 to 4 cm and coincides with the interval weremost of the organic carbon oxidation takes place. This indicates that the reactive fractionof organic matter, commonly assumed to be marine, has a more negative 13C orgthan the refractory fraction, usually held to be terrestrial. Palaeoproductivity estimates calculated from thesediment data by means of literature algorithms yield low surface productivities(12–88 gC m-2 y-1), which are in good agreement with field measurements of primary productivity in otherstudies. Such values are, however, significantly lower than those indicated by recent productivitymaps of the area derived from satellite imagery ({\textgreater}100 gC m-2 y-1).},
author = {{Van Santvoort}, P. J M and {De Lange}, G. J. and Thomson, J. and Colley, S. and Meysman, F. J R and Slomp, C. P.},
doi = {10.1023/A:1024271706896},
isbn = {1380-6165},
issn = {13806165},
journal = {Aquatic Geochemistry},
keywords = {210Pb,Diagenesis,Eastern Mediterranean,Organic carbon,Oxidation,Production,$\delta$13C},
number = {3},
pages = {153--175},
title = {{Oxidation and origin of organic matter in surficial Eastern Mediterranean hemipelagic sediments}},
volume = {8},
year = {2002}
}
@article{Aller1998,
abstract = {The activities of infaunal macrobenthos strongly influence the pathways, rates, and extent of organic matter remineralization and associated reactions in marine sediments. Solute transport during irrigation is a particularly important process that stimulates microbial activity and net remineralization, both within and adjacent to the bioturbated zone. Part of the stimulation proximal to the bioturbated zone is due to redox oscillation and oxidant supply during transport, but part of both the near and far-field effects are a result of other factors. Experiments designed to simulate different degrees of diffusive exchange, and thus infaunal abundances or activity, demonstrate a regular and strong dependence of anaerobic remineralization on diffusive transport. For example, net production of NH4+, HPO4-, I-, and Mn++ increases as the effective distance between burrows becomes less than or similar to 2 cm (burrow abundance greater than or similar to 800 m(-2)) in otherwise identical anoxic sediment. Corresponding changes in sedimentary bacterial numbers, exoenzyme activity, per cell growth rate (RNA), and solid phase properties (N, C/N, P) indicate that the increases in net rates are due in part to an absolute increase in total production. Transport-reaction models and experimental results demonstrate that relative decreases in the uptake of solutes into biomass, abiogenic precipitation reactions, and increased removal of inhibiting metabolites all occur simultaneously, enhancing both total and net remineralization. The phenonomenological first-order rate constant for organic matter decomposition is therefore a function not only of the reductant and oxidant pool properties, but also the environmental transport regime. Solid phase reaction products can differ substantially as a function of diffusive openness. For example, both organic P and the organic P/inorganic P ratio increase in more diffusively-open (irrigated) compared to diffusively-closed, anoxic sediment. The sensitivity of solute concentrations, microbial activity and diagenetic reaction balances to diffusive transport regime, indicates that macrofauna can functionally manipulate these properties through relatively small changes in burrow spacing patterns and individual burrow geometries.},
author = {Aller, Robert C. and Aller, Josephine Y.},
doi = {10.1357/002224098321667413},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Aller, The effect of biogenic irrigation intensity and solute, 1998.pdf:pdf},
isbn = {0022-2402},
issn = {00222402},
journal = {Journal of Marine Research},
number = {4},
pages = {905--936},
title = {{The effect of biogenic irrigation intensity and solute exchange on diagenetic reaction rates in marine sediments}},
volume = {56},
year = {1998}
}
@article{Fleming-Lehtinen2008,
abstract = {Eutrophication is an ongoing process in most parts of the Baltic Sea. This article reports on the changes during recent decades of several eutrophication-related variables in the open sea areas surrounding Finland (wintertime nutrient concentrations, wintertime nutrient ratios, and summer time chlorophyll alpha concentrations at the surface). The sum of nitrate- and nitrite-nitrogen ([NO3+NO2]-N) was observed to increase nearly fourfold in the Northern Baltic Proper and the Gulf of Finland and almost double in the Bothnian Sea from the 1960s until the 1980s or 1990s. The increase was followed by a decrease, which was modest in the two former subregions. Phosphate-phosphorus (PO4-P) concentrations followed a similar pattern in the Northern Baltic Proper (threefold increase and subsequent slight decrease) and Bothnian Sea (30{\%} increase and subsequent decrease), but increased throughout the study in the Gulf of Finland, with the present concentration being threefold to the measurements made in the early 1970s. The PO4-P concentration decreased throughout the study in the Bothnian Bay. Silicate-silicon (SiO4-Si) concentrations decreased 30-50{\%} from the early 1970s to the late 1990s and increased 20-40{\%} thereafter in the Northern Baltic Proper, the Gulf of Finland, and the Bothnian Sea. Chlorophyll alpha showed an increase of over 150{\%} in the Northern Baltic Proper and the Gulf of Finland from the 1970s until the early 2000s. In the Bothnian Sea the chlorophyll alpha concentration increased more than 180{\%} from the late 1970s until the late 1990s, and decreased thereafter. According to these long-term observations, the Gulf of Finland and Northern Baltic Proper show clear signs of eutrophication, which may be emphasized by hydrographical changes affecting the phytoplankton communities and thus the algal biomass.},
author = {Fleming-Lehtinen, Vivi and Laamanen, Maria and Kuosa, Harri and Haahti, Hannu and Olsonen, Riitta},
doi = {10.1579/0044-7447(2008)37[86:LDOINA]2.0.CO;2},
isbn = {00447447},
issn = {0044-7447},
journal = {Ambio},
number = {2},
pages = {86--92},
pmid = {18488550},
title = {{Long-term development of inorganic nutrients and chlorophyll alpha in the open northern Baltic Sea.}},
volume = {37},
year = {2008}
}
@article{Gillibrand2005,
abstract = {The sea lochs (fjords) of NW Scotland bridge the land-ocean interface in a region of Europe which is particularly well situated to monitor changes in westerly air streams. Inter-annual atmospheric circulation changes at this latitude are largely governed by the North Atlantic Oscillation (NAO). Comparing two recent extreme NAO years, a two-dimensional model of Loch Sunart, NW Scotland, is used to examine the potential effects of climate oscillations on the magnitude and frequency of deep-water renewal events and the resulting water properties in the fjord basins. In the upper basin of the fjord, meteorological forcing during the high NAO index year (1988-89) resulted in less-frequent deep-water renewal, greater variability in basin salinity and a lower annual-mean salinity (by 0.52) than that predicted for the low NAO index year (1995-96). In the main basin, variations in meteorological forcing had much less effect on basin water properties. In both basins, predicted deep water inflow was significantly greater during the negative phase NAO, with annual inflow to the upper and main basins being respectively 50{\%} and 300{\%} greater during 1995-96 relative to 1988-99. Through a sensitivity analysis, the NAO is shown to affect upper basin water properties through the influence of low-frequency anomalies in the meteorological forcing, particularly the enhanced westerly wind stress associated with positive phases, which inhibits deep water renewal over the winter months. The salinity of the main and upper basins respond differently to the boundary forcing due to differential tidal mixing above the respectively sub- and super-critical entrance sills. Predictions of basin water isotope ratios are made by applying the salinity:$\delta$18Owatermixing line for the region to the salinity results; the combination of the weak dependence of $\delta$18Owateron salinity and the stable salinity predicted for the main basin suggests that some fjord basins may provide ideal sites for palaeotemperature studies. {\textcopyright} 2004 Elsevier Ltd. All rights reserved.},
author = {Gillibrand, P. A. and Cage, A. G. and Austin, W. E.N.},
doi = {10.1016/j.csr.2004.10.011},
isbn = {0278-4343},
issn = {02784343},
journal = {Continental Shelf Research},
keywords = {Basin water salinity,NAO,Numerical model,Oxygen isotopes,Scottish sea loch},
number = {5-6},
pages = {571--587},
title = {{A preliminary investigation of basin water response to climate forcing in a Scottish fjord: Evaluating the influence of the NAO}},
volume = {25},
year = {2005}
}
@article{Pokrovsky2002,
abstract = {The chemical status of major and trace elements (TE) in various boreal small rivers and watershed has been investigated along a 1500-km transect of NW Russia. Samples were filtered in the field through a progressively decreasing pore size (5, 0.8 and 0.22 $\mu$m 100, 10, and 1 kD) using a frontal filtration technique. All major and trace elements and organic carbon (OC) were measured in filtrates and ultrafiltrates. Most rivers exhibit high concentration of dissolved iron (0.2-4 mg/l), OC (10-30 mg/l) and significant amounts of trace elements usually considered as immobile in weathering processes (Ti, Zr, Th, Al, Ga, Y, REE, V, Pb). In (ultra) filtrates, Fe and OC are poorly correlated: iron concentration gradually decreases upon filtration from 5 $\mu$m to 1 kD whereas the major part of OC is concentrated in the {\textless}1-10 kD fraction. This reveals the presence of two pools of colloids composed of organic-rich and Fe-rich particles. According to their behavior during filtration and association with these two types of colloids, three groups of elements can be distinguished: (i) species that are not affected by ultrafiltration and are present in the form of true dissolved inorganic species (Ca, Mg, Li, Na, K, Sr, Ba, Rb, Cs, Si, B, As, Sb, Mo) or weak organic complexes (Ca, Mg, Sr, Ba), (ii) elements present in the fraction smaller than 1-10 kD prone to form inorganic or organic complexes (Mn, Co, Ni, Zn, Cu, Cd, and, for some rivers, Pb, Cr, Y, HREE, U), and (iii) elements strongly associated with colloidal iron in all ultrafiltrates (P, Al, Ga, REE, Pb, V, Cr, W, Ti, Ge, Zr, Th, U). Based on size fractionation results and taking into account the nominal pore size for membranes, an estimation of the effective surface area of Fe colloids was performed. Although the total amount of available surface sites on iron colloids (i.e., 1-10 $\mu$M) is enough to accommodate the nanomolar concentrations of dissolved trace elements, very poor correlation between TE and surface sites concentrations was observed in filtrates and ultrafiltrates. This strongly suggests a preferential transport of TE as coprecipitates with iron oxy(hydr)oxides. These colloids can be formed on redox boundaries by precipitation of Fe(III) from inflowing Fe(II)/TE-rich anoxic ground waters when they meet well-oxygenated surface waters. Dissolved organic matter stabilizes these colloids and prevents their aggregation and coagulation. Estuarine behavior of several trace elements was studied for two small iron- and organic-rich rivers. While Si, Sr, Ba, Rb, and Cs show a clear conservative behavior during mixing of freshwaters with the White sea, Al, Pb and REE are scavenged with iron during coagulation of Fe hydroxide colloids. {\textcopyright} 2002 Elsevier Science B.V. All rights reserved.},
author = {Pokrovsky, O. S. and Schott, J.},
doi = {10.1016/S0009-2541(02)00115-8},
isbn = {0009-2541},
issn = {00092541},
journal = {Chemical Geology},
keywords = {Boreal river,Estuary,Iron colloids,Organic matter,Trace elements},
number = {1-4},
pages = {141--179},
pmid = {179349900009},
title = {{Iron colloids/organic matter associated transport of major and trace elements in small boreal rivers and their estuaries (NW Russia)}},
volume = {190},
year = {2002}
}
@book{Soetaert2008,
author = {Soetaert, Karline and Herman, Peter M J},
isbn = {1402086245},
publisher = {Springer Science {\&} Business Media},
title = {{A practical guide to ecological modelling: using R as a simulation platform}},
year = {2008}
}
@article{VanCappellen1996,
abstract = {This paper presents a multicomponent early diagenetic model which explicitly accounts for the coupling of the redox cycles of Fe and Mn to those of oxygen, carbon, sulfur, and nitrogen. Rate expressions are used to represent the oxidation of organic carbon, the oxidation of secondary reduced species formed as byproducts of organic matter oxidation, and the precipitation and dissolution of sulfide and carbonate minerals. The net rate of organic carbon oxidation is broken down into the contributions of aerobic respiration, denitrification, dissimilatory Mn(IV) reduction, dissimilatory Fe(III) reduction, sulfate reduction, and methanogenesis. The computational algorithm is based on a modified Monod kinetics formulation for the organic matter degradation pathways. The non-specific adsorption of ammonia, the surface complexation of Fe2+ and Mn2+ cations, and the homogeneous interconversions within the dissolved carbonate-sulfide system are treated as equilibrium reactions. The transport processes included are sediment advection, pore water diffusion, and particle mixing and irrigation by benthic macrofauna. Chemical component concentrations and pore water alkalinity are described by a set df continuity equations characterized by nonlinear reaction rate terms. The equations are solved by finite-difference. The distribution of pore water pH is derived from the calculated profiles of total dissolved inorganic carbon, total dissolved sulfide, and alkalinity. Particulate deposition fluxes and bottom water composition are imposed as upper boundary conditions. The model is applied to an extensive set of data collected in a marine sediment from the Skagerrak (Denmark). Theoretical depth profiles reproduce the measured pore water concentrations of O-2, NO3-, NH4+, Mn2+. and Fe2+ ins the solid sediment concentrations of Fe(III), Mn(TV), sulfide-bound Fe(II), and non-sulfide Fe(II). The model also correctly simulates the depth distribution of measured sulfate reduction rates. According to the computations, approximately two thirds of the total rate of iron reduction in the sediment are utilized directly by bacteria to oxidize organic carbon (dissimilatory Fe reduction). Manganese reduction, on the other hand, is mostly due to chemical reaction with dissolved Fe2+. Despite the relatively high rates of iron and manganese reduction, only very small amounts of the Fe(II) and Mn(II) produced during early diagenesis are permanently buried in the deeper sediment. Most of the dissolved and solid-bound Fe(II) and Mn(II) cations reoxidize in the surface sediment or escape to the water column. The main oxidation pathways in the sediment are heterogeneous oxygenation of surface complexed Fe2+ and Mn2+ cations. The model also predicts that intense redox cycling of Fe and Mn should cause the appearance of a pH minimum at the base of the aerobic surface layer.},
archivePrefix = {arXiv},
arxivId = {0904.2111},
author = {{Van Cappellen}, Philippe and Wang, Yifeng},
doi = {10.2475/ajs.296.3.197},
eprint = {0904.2111},
isbn = {0002-9599},
issn = {00029599},
journal = {American Journal of Science},
pmid = {293},
title = {{Cycling of iron and manganese in surface sediments: A general theory for the coupled transport and reaction of carbon, oxygen, nitrogen, sulfur, iron, and manganese}},
year = {1996}
}
@article{Wu1995,
abstract = {Total and labile Fe measurements, and Fe3+ titrations were carried out both at sea and in the laboratory with adsorptive cathodic stripping voltammetry (CSV) methods using 1-nitroso-2-naphthol (1N2N) as a complexing ligand to study Fe(III) speciation and the kinetic interaction of Fe3+ with naturally occurring organic ligands. On the continental slope and at the shelf/slope front of the Northwest Atlantic ocean, the total dissolved ({\textless} 0.4 $\mu$m) Fe was predominantly 1N2N nonlabile, with 60{\%} nonlabile at the mouth of Delaware Bay. The exact chemical speciation of this nonlabile Fe is not known; although some of this Fe is likely in strong organic complexes with a KFeL1023.22 as determined by a competitive ligand equilibration/cathodic stripping voltammetry (CLE/CSV) method. To obtain kinetic information on Fe3+ uptake by natural ligands in excess of ambient Fe3+ concentrations in seawater, Fe3+ was added to UV irradiated seawater samples with and without the model ligands, EDTA and enterobactin. Measurable Fe in UV seawater with model ligands decreased with time much faster than that without model ligands. Similar faster decreases of measurable Fe with time were observed for field samples, suggesting the existence of Fe(III) complexing organic ligands. The reaction kinetics of the added Fe3+ with natural organic ligands and of the Fe(III)-organic complexes with 1N2N suggested that there were different organic ligands in different oceanographic regimes. Two classes of ligands are distinguished from these studies; one class which binds to Ca and Mg and another which does not. The latter assessment could not be unambiguously determined by a CLE/CSV method. Our kinetic experiments indicate that equilibrium is not achieved at the same rate in all natural samples studied and that different ligands occur in different water masses. The maximum second-order rate constant determined for Fe3+ uptake by natural ligands in our field samples is 106 M-1s-1. Using a CLE/CSV method at pH 6.9 with complete equilibrium established for the samples, a KFeLCL value of {\textless} 1012.04 ± 0.09 is calculated for the excess ligands in these samples. These data are in agreement with our detailed kinetic analysis using the steady state approximation based on natural ligand dissociation from FeL and recovery of that Fe by 1N2N at pH 8. KFeL (1020.6 M-1) estimated from kinetic data is within the range of estimates made by researchers using only the CLE/CSV approach. {\textcopyright} 1995.},
author = {Wu, Jingfeng and Luther, George W.},
doi = {10.1016/0304-4203(95)00033-N},
isbn = {0304-4203},
issn = {03044203},
journal = {Marine Chemistry},
number = {1-4},
pages = {159--177},
title = {{Complexation of Fe(III) by natural organic ligands in the Northwest Atlantic Ocean by a competitive ligand equilibration method and a kinetic approach}},
volume = {50},
year = {1995}
}
@article{Soetaert2012a,
abstract = {The concentrations of many natural compounds are altered by chemical and biological transformations, and physical processes such as adsorption and transport. Their fate can be predicted using reactive transport models that describe reaction and advective and dispersive movement of these components in their natural environment. Recently a number of software packages have been implemented in the open source software R that allow one to implement reactive transport models. Central to this is the ReacTran R-package, a comprehensive collection of functions for modeling reactive components that may be distributed over multiple phases, whose dynamics are coupled through biological and geochemical reactions, and that are transported in one-, two- or three-dimensional domains with simple geometries. Dedicated solution methods are in R-packages deSolve and rootSolve. The modeling packages facilitate the simulation of reaction and transport of components for spatial scales ranging from micrometers to kilometers and spanning multiple time-scales. As they are influenced in similar ways, the same functions can solve biogeochemical models of the sediment, groundwater, rivers, estuaries, lakes or water columns, experimental setups, or even describe reaction and transport within flat, cylindrical or spherical bodies, such as organisms, aggregates, or the dispersion of individuals on flat surfaces and so on. We illustrate the use of R for reactive transport modeling by three applications spanning several orders of magnitude with respect to spatial and temporal scales. They comprise (1) a model of an experimental flow-through sediment reactor, where fitting so-called breakthrough curves are used to derive sulfate reduction rates in an estuarine sediment, (2) a conservative and reactive tracer addition experiment in a small stream, which implements the concept of river spiraling, and (3) a 2-D and 3-D model that describes oxygen dynamics in the upper layers of the sediment, interspersed with several hotspots of increased reaction intensities. The packages ReacTran, deSolve and rootSolve are implemented in the software R and thus available for all popular platforms (Linux, Windows, Mac). Models implemented using this software are short and easily readable, yet they are efficiently solved. This makes R extremely well suited for rapid model prototyping. ?? 2011 Elsevier Ltd.},
author = {Soetaert, Karline and Meysman, Filip},
doi = {10.1016/j.envsoft.2011.08.011},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Soetaert, Reactive transport in aquatic ecosystems, 2012.pdf:pdf},
isbn = {1364-8152},
issn = {13648152},
journal = {Environmental Modelling and Software},
keywords = {Model,Open source,R,Reactive transport,Software},
pages = {49--60},
publisher = {Elsevier Ltd},
title = {{Reactive transport in aquatic ecosystems: Rapid model prototyping in the open source software R}},
url = {http://dx.doi.org/10.1016/j.envsoft.2011.08.011},
volume = {32},
year = {2012}
}
@article{Froelich1979,
abstract = {Pore water profiles of total-CO2, pH, PO3-4, NO-3 plus NO-2, SO2-4, S2-, Fe2+ and Mn2+ have been obtained in cores from pelagic sediments of the eastern equatorial Atlantic under waters of moderate to high productivity. These profiles reveal that oxidants are consumed in order of decreasing energy production per mole of organic carbon oxidized (O2 {\textgreater} manganese oxides {\~{}} nitrate {\textgreater} iron oxides {\textgreater} sulfate). Total CO2 concentrations reflect organic regeneration and calcite dissolution. Phosphate profiles are consistent with organic regeneration and with the effects of release and uptake during inorganic reactions. Nitrate profiles reflect organic regeneration and nitrate reduction, while dissolved iron and manganese profiles suggest reduction of the solid oxide phases, upward fluxes of dissolved metals and subsequent entrapment in the sediment column. Sulfate values are constant and sulfide is absent, reflecting the absence of strongly anoxic conditions. {\textcopyright} 1979.},
author = {Froelich, P. N. and Klinkhammer, G. P. and Bender, M. L. and Luedtke, N. A. and Heath, G. R. and Cullen, Doug and Dauphin, Paul and Hammond, Doug and Hartman, Blayne and Maynard, Val},
doi = {10.1016/0016-7037(79)90095-4},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Froelich, Early oxidation of organic matter in pelagic sediments of the eastern equatorial Atlantic suboxic diagenesis, 1979.pdf:pdf},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
number = {7},
pages = {1075--1090},
pmid = {9457},
title = {{Early oxidation of organic matter in pelagic sediments of the eastern equatorial Atlantic: suboxic diagenesis}},
volume = {43},
year = {1979}
}
@article{Malmgren1992,
abstract = {Sedimentation of river transported particles in the Ore Estuary was studied during spring flow (April- May, 1989) . River input was calculated as the product of discharge and particle concentration in the river water . The concentration of suspended matter in the estuary water was determined with a lightscattering probe at 25 depth profiles throughout the estuary . The sedimentation was measured using sediment traps on 5 stations along a line from the river mouth to the mouth of the estuary . Sampling was carried out on four dates with different water discharge . The extension of the particle plume varied during the observation period mainly due to variation in river discharge . The maximum extension of the river plume occurred during the peak of the spring flow and covered approximately 70{\%} of the estuary area . The sedimentation rates were generally high and the average retention time for a particle in the water column was less than 1 day which verifies that the river transported fine-grained particles are primary deposited within the estuary . The major part of the river input of suspended matter was deposited near the river mouth . There was a surplus of the total sedimentation compared to the river input which was due to wave-induced resuspension, especially in the eastern part of the estuary .},
author = {Malmgren, Louise and Brydsten, Lars},
doi = {10.1007/BF00026200},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Malmgren,Ore{\_}estuary.pdf:pdf},
issn = {0018-8158},
journal = {Hydrobiologia},
keywords = {estuary,river plume,sedimentation},
number = {1},
pages = {59--69},
title = {{Sedimentation of river-transported particles in the Ore estuary, northern Sweden}},
volume = {235-236},
year = {1992}
}
@article{Dijkstra2016,
abstract = {Phosphorus (P) is an essential nutrient for marine organisms. Its burial in hypoxic and anoxic marine basins is still incompletely understood. Recent studies suggest that P can be sequestered in sediments of such basins as reduced iron (Fe)-P but the exact phase and the underlying mechanisms that lead to its formation are unknown. In this study, we investigated sediments from the deepest basin in the Baltic Sea, the Landsort Deep (site M0063), that were retrieved during the Integrated Ocean Drilling Project (IODP) Baltic Sea Paleoenvironment Expedition 347. The record comprises the whole brackish/marine Littorina Sea stage including past intervals of extensive hypoxia in the Baltic Sea that occurred during the Holocene Thermal Maximum (HTMHI) and the Medieval Climate Anomaly (MCA1HI and MCA2HI). Various redox proxies (e.g. the presence of laminations and high Mo contents) suggest almost permanent bottom water hypoxia during the Littorina Sea stage in the Landsort Deep. The bottom waters were likely even seasonally anoxic or sulfidic during the MCA1HI and MCA2HI, and permanently sulfidic during the HTMHI. With the use of micro-analysis of sieved minerals (SEM-EDS, XRD and synchrotron-based XAS), we show that Mn- and Mg-rich vivianite crystals are present at various depths in the Littorina Sea sediments. We also have indications for vivianite in the MCA1HI, MCA2HI and HTMHI deposits. The formation of vivianite thus likely explains the high Fe-bound P fraction throughout the whole Littorina Sea stage. Shuttling of Fe and Mn from the shelves into the basin and high inputs of P in settling organic matter are likely key drivers for vivianite formation. Our study shows that vivianite can likely form in near-surface sediments under a broad range of bottom water redox conditions, varying from hypoxic and anoxic to sulfidic.},
author = {Dijkstra, Nikki and Slomp, Caroline P. and Behrends, Thilo},
doi = {10.1016/j.chemgeo.2016.05.025},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Dijkstra, vivianite landsort deep 2016.pdf:pdf},
issn = {00092541},
journal = {Chemical Geology},
keywords = {Baltic Sea Basin Paleoenvironment,Integrated Ocean Drilling Program,Landsort Deep,Phosphorus burial,Shelf-to-basin shuttle,Vivianite},
pages = {58--72},
publisher = {Elsevier B.V.},
title = {{Vivianite is a key sink for phosphorus in sediments of the Landsort Deep, an intermittently anoxic deep basin in the Baltic Sea}},
url = {http://dx.doi.org/10.1016/j.chemgeo.2016.05.025},
volume = {438},
year = {2016}
}
@article{Hartzell2017,
author = {Hartzell, Jeanne L and Jordan, Thomas E and Cornwell, Jeffrey C},
issn = {1559-2723},
journal = {Estuaries and Coasts},
pages = {1--19},
publisher = {Springer},
title = {{Phosphorus sequestration in sediments along the salinity gradients of Chesapeake Bay subestuaries}},
year = {2017}
}
@article{Soetaert1996,
abstract = {We present a numerical model of sedimentary early diagenetic processes that includes oxic and anoxic mineralization. The model belongs to the new wave of early diagenesis models that account for depth-dependent bioturbation and porosity profiles; it can be used both for calculating steady-state conditions and transient simulation. It was developed to reproduce the cycling of carbon, oxygen, and nitrogen along the ocean margin; it resolves the sediment-depth profiles of carbon, oxygen, nitrate, ammonium, and other reduced substances. Organic carbon is modeled as two degradable fractions with different first-order degradation rates and nitrogen:carbon ratios, to account for the decreasing reactivity and N/C ratio of the organic matter with depth into the sediment. The consumption of oxygen and nitrate as terminal electron acceptors is explicitly modeled, and mineralization is limited both by carbon (first order kinetics) and by oxidant availability (Michaelis-Menten type kinetics). Nitrification and oxic mineralization are decoupled, which allows the description of ammonium profiles. Mineralization processes using other oxidants (manganese oxides, iron oxides, sulphate) are lumped into one process, where degradation is only carbon limited; the terminal electron acceptors are not explicitly modeled, only the production of reduced substances is described. These substances are in part permanently removed (e.g., pyrite formation below the bioturbation zone) and partly diffuse towards the oxic layer where they react with oxygen. The values of several parameters were constrained using literature-derived relationships. The model was calibrated on a dataset obtained from the literature, which relates the magnitude of the different pathways to total organic carbon mineralization. The influence of carbon flux, bioturbation, sedimentation rate, bottomwater concentrations of oxygen, and nitrate and carbon degradability on the different mineralization pathways is examined. The relative contribution of the oxic mineralization in the model is significantly depressed under high organic flux, under low bottomwater oxygen conditions and when the bioturbation increases; higher carbon degradability has only a small positive effect, while sedimentation rate is relatively unimportant. Denitrification is mainly influenced by the nitrate concentration in the overlying bottomwater.},
author = {Soetaert, Karline and Herman, Peter M J and Middelburg, Jack J.},
doi = {10.1016/0016-7037(96)00013-0},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/soetaert, diagenetic model.pdf:pdf},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
number = {6},
pages = {1019--1040},
title = {{A model of early diagenetic processes from the shelf to abyssal depths}},
volume = {60},
year = {1996}
}
@article{Ruttenberg1993,
abstract = {Evidence for precipitation of authigenic carbonate fluorapatite (CFA) in Long Island Sound and Mississippi Delta sediments suggests that formation of CFA is not restricted to environments of active coastal upwelling. We present porewater data suggestive of CFA formation in both these areas. Application of a sequential leaching procedure, designed specifically to separate authigenic carbonate fluorapatite from other phosphorus-containing phases, including detrital apatite of igneous or metamorphic origin, provides strong supporting evidence for authigenic apatite formation in these sediments. The size of the authigenic apatite reservoir increases with depth, indicating continued formation of CFA during early diagenesis. This depth increase is mirrored by a decrease in solid-phase organic P at both sites, suggesting that CFA is forming at the expense of organic P. Mass balance considerations, application of diagenetic models to interstitial water nutrient data and the saturation state of the interstitial water are consistent with this interpretation. Diagenetic redistribution of phosphorus among the different solid-phase reservoirs is observed at both sites and results in near perfect retention of P by these sediments over the depth intervals sampled. Formation of CFA in continental margins which do not conform to the classically defined regions of phosphorite formation renders CFA a quantitatively more important sink than has previously been recognized. Including this reservoir as a newly identified sink for reactive P in the ocean, the residence time of P in the modern ocean must be revised downward. The implication for ancient oceans of CFA formation in continental margin sediments other than phosphorites is that phosphorite formation may be less a representation of episodicity in removal of reactive P from the oceans than of localized concentration of CFA in phosphatic sediments by secondary physical processes. ?? 1993.},
author = {Ruttenberg, Kathleen C. and Berner, Robert A.},
doi = {10.1016/0016-7037(93)90035-U},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Ruttenberg, Authigenic apatite formation and burial in sediments from non-upwelling, 1992.pdf:pdf},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
number = {5},
pages = {991--1007},
title = {{Authigenic apatite formation and burial in sediments from non-upwelling, continental margin environments}},
volume = {57},
year = {1993}
}
@article{Boudreau1984,
author = {Boudreau, Bernard P},
issn = {0022-2402},
journal = {Journal of Marine Research},
number = {3},
pages = {731--735},
publisher = {Sears Foundation for Marine Research},
title = {{On the equivalence of nonlocal and radial-diffusion models for porewater irrigation}},
volume = {42},
year = {1984}
}
@article{Moodley2005,
abstract = {Clarification of the factors involved in the formation of unusual ancient organic carbon- rich deposits (like eastern Mediterranean sapropels) is central in understanding oceanic carbon cycling. The role of oxygenation remains a subject of controversy primarily due to two major uncertainties: (1) it is unknown if ancient organic-rich deposits reflect an accumulation of refractory organic matter (OM) or oxygenation-related aberrant sediment OM recycling, and (2) although marine OM degradation may be slower under anoxic conditions, its ultimate impact on organic carbon (Corg) preservation over geological time remains unclear. Here we provide direct experimental evidence that the Corg in eastern Mediterranean S1 sapropels (deposited {\textgreater}5 ka) is still highly reactive and that a shutdown in labile organic matter degradation under anoxic conditions played a key role in the formation of these deposits.},
author = {Moodley, Leon and Middelburg, Jack J. and Herman, Peter M J and Soetaert, Karline and de Lange, Gert J.},
doi = {10.1130/G21731.1},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Moodley 2005, geology.pdf:pdf},
isbn = {0091-7613},
issn = {00917613},
journal = {Geology},
keywords = {Carbons isotopes,Nitrogen isotopes,Organic carbon,Preservation,Remineralization,Sapropel},
number = {11},
pages = {889--892},
pmid = {16859},
title = {{Oxygenation and organic-matter preservation in marine sediments: Direct experimental evidence from ancient organic carbon-rich deposits}},
volume = {33},
year = {2005}
}
@article{Li2015,
abstract = { Nutrient contamination has been one of the lingering issues in the Chesapeake Bay because the bay restoration is complicated by temporally and seasonally variable nutrient sources and complex interaction between imported and regenerated nutrients. Differential reactivity of sedimentary phosphorus (P) pools in response to imposed biogeochemical conditions can record past sediment history and therefore a detailed sediment P speciation may provide information on P cycling particularly the stability of a P pool and the formation of one pool at the expense of another. This study examined sediment P speciation from three sites in the Chesapeake Bay: (i) a North site in the upstream bay, (ii) a middle site in the central bay dominated by seasonally hypoxic bottom water, and (iii) a South site at the bay-ocean boundary using a combination of sequential P extraction (SEDEX) and spectroscopic techniques, including 31P NMR, P X-ray absorption near edge structure spectroscopy (XANES), and Fe extended X-ray absorption fine structure (EXAFS). Results from sequential P extraction reveal that sediment P is composed predominantly of ferric Fe-bound P and authigenic P, which was further confirmed by solid-state 31P NMR, XANES, and EXAFS analyses. Additionally, solution 31P NMR results show that the sediments from the middle site contain high amounts of organic P such as monoesters and diesters, compared to the other two sites, but that these compounds rapidly decrease with sediment depth indicating remineralized P could have precipitated as authigenic P. Fe EXAFS enabled to identify the changes in Fe mineral composition and P sinks in response to imposed redox condition in the middle site sediments. The presence of lepidocrocite, vermiculite, and Fe smectite in the middle site sediments indicates that some ferric Fe minerals can still be present along with pyrite and vivianite, and that ferric Fe-bound P pool can be a major P sink in anoxic sediments. These results provide improved insights into sediment P dynamics, particularly the rapid remineralization of organic P and the stability of Fe minerals and the ferric Fe-bound P pool in anoxic sediments in the Chesapeake Bay. },
author = {Li, Wei and Joshi, Sunendra R and Hou, Guangjin and Burdige, David J and Sparks, Donald L and Jaisi, Deb P},
doi = {10.1021/es504648d},
issn = {1520-5851},
journal = {Environmental Science {\&} Technology},
number = {1},
pages = {203--211},
pmid = {25469633},
title = {{Characterizing Phosphorus Speciation of Chesapeake Bay Sediments Using Chemical Extraction, 31P NMR, and X-ray Absorption Fine Structure Spectroscopy}},
url = {http://dx.doi.org/10.1021/es504648d},
volume = {49},
year = {2015}
}
@article{Jordan2008,
abstract = {We used sequential extractions to quantify different forms of particulate phosphorus (PP) in sediments along the salinity gradient of the Patuxent River estuary. About 50–90{\%} of the PP was phosphate bound to iron oxides (Fe-P), and 8–30{\%} was organic P (org-P). Loosely sorbed phosphate (sorb-P), detrital apatite, and authigenic plus biogenic apatite each made up ,10{\%} of the PP. Suspended sediments from the watershed and deposited sediments in tidal freshwater had the highest concentrations of Fe-P, ranging about 30–55 mmol g21 sediment. As pore-water salinity increased to 7 along the estuarine gradient, Fe-P declined to 15–25 mmol g21, org-P increased from 4 to 10 mmol g21, sorb-P increased from 0.5 to 2.5 mmol g21, and total sediment PP declined from 60 to 40 mmol g21. Concentrations of pore-water solutes also changed with salinity. As salinity increased, dissolved Fe and ammonium decreased, while dissolved phosphate increased. Near the freshwater end of the gradient, the molar ratio of pore-water ammonium : phosphate was generally .16 (the Redfield ratio) and ranged up to .700, while at the saline end of the gradient the ratio was generally ,16 and ranged down to ,1.5. Our observations are consistent with the hypothesis that phosphate is released from terrigenous sediments when they are deposited in saline portions of the estuary where sulfide may enhance dissolution of Fe-P and form Fe sulfide precipitates. Such phosphate release may contribute to the generally observed switch from phosphorus limitation in freshwater to nitrogen limitation in coastal marine water.},
author = {Jordan, Thomas E. and Cornwell, Jeffrey C. and Boynton, Walter R. and Anderson, Jon T.},
doi = {10.4319/lo.2008.53.1.0172},
isbn = {0024-3590},
issn = {0024-3590},
journal = {Limnology and Oceanography},
number = {1},
pages = {172--184},
title = {{Changes in phosphorus biogeochemistry along an estuarine salinity gradient: The iron conveyer belt}},
volume = {53},
year = {2008}
}
@article{Wang1996,
abstract = {STEADYSED1 is a multicomponent reactive transport code for steady-state early diagenesis which fully incorporates the reaction couplings among the elements, C, O, N, S, Fe, and Mn. The model is tested against extensive datasets collected by Canfield et al. (1993a,b) at three coastal marine sites that exhibit high rates of combined iron and manganese (hydr)oxide reduction. It is shown that the model provides a consistent explanation of the entire body of multicomponent multisite observations. The measured concentration profiles of twenty-eight individual porewater and solid sediment species are satisfactorily reproduced. Furthermore, the model predicts the observed distributions of sulfate reduction rates, as well as diagnostic features of the porewater pH profiles. The coupled nature of the reactive species imposes stringent constraints when fitting model-calculated distributions to the data, because a single set of reaction and transport parameters must account for the profiles of all the species at each site. The parameters are further separated into site-specific (e.g., deposition fluxes, bottom water composition) and reaction-specific parameters (e.g., rate coefficients, apparent equilibrium constants, limiting substrate concentrations). By minimizing the variations of the reaction-specific parameters from one site to another, the fitting strategy emphasizes the retrieval from field data of reaction parameters that are mechanistically meaningful. The model reproduces the significant vertical overlap between organic carbon oxidation pathways observed in the sediments. The overlap is explained by the combination of high rates of organic carbon oxidation plus intense bioturbation and irrigation at the sites studied. The model-derived contributions of the various respiratory processes compare favorably with the incubation results of Canfield et al. (1993a,b). Aerobic respiration accounts for less than 32{\%} of total organic carbon oxidation at the three sites. From 22 to 46{\%} of the O-2 uptake by the sediments is directly coupled to organic carbon oxidation, while the remainder is used for the oxidation of secondary reduced species, in particular dissolved, adsorbed and solid Fe(II) and Mn(II) species. According to the model, the oxidation of Fe2+ by Mn (hydr)oxides is responsible for the observed spatial separation of the porewater build-up of Mn2+ and Fe2+. At two of the sites, 75 and 97{\%} of the total rate of Mn oxide reduction is due to chemical reaction with dissolved Fe2+. In contrast, at the same sites, iron (hydr)oxides are mostly utilized by bacteria for the oxidation of organic matter (dissimilatory iron reduction). As shown also by Canfield et al. (1993a,b), dissimilatory reduction is the principal dissolution pathway for manganese oxides at the third site. A sensitivity analysis suggests that, for given deposition fluxes of reactive Fe and Mn, the competition between dissimilatory and nondissimilatory metal reduction pathways depends primarily on the total carbon oxidation rate and the intensity of porewater irrigation. The simulations also highlight the importance of adsorption-desorption of Fe(II) and Mn(II) in the redox cycling of the metals, as well as their impact on porewater alkalinity and pH. Based on the calculated rate distributions, detailed budgets of Fe, Mn, and O-2 in the sediments are presented. The model-calculated benthic exchange fluxes of solutes are dominated by irrigation. For nitrate, molecular diffusion and irrigation cause fluxes in opposite directions. As a result, there is a net transfer of nitrate from the water column to the sediments, although the interfacial porewater gradients predict diffusional fluxes out of the sediments. A significant fraction of the benthic Fe and Mn fluxes to the bottom waters may be due to desorption at the water-sediment interface.},
author = {Wang, Y F and {Van Cappellen}, P},
doi = {10.1016/0016-7037(96)00140-8},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/wang, reactive transport modelling.pdf:pdf},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica Et Cosmochimica Acta},
keywords = {iron reduction,manganese reduction,mathematical-model,mn,natural-waters,organic-matter,oxidation-kinetics,oxygen,sea-water,sulfate reduction},
number = {16},
pages = {2993--3014},
title = {{A multicomponent reactive transport model of early diagenesis: Application to redox cycling in coastal marine sediments}},
volume = {60},
year = {1996}
}
@article{Sivan2011a,
abstract = {Anaerobic oxidation of methane (AOM) by sulfate has been recognized as a critical process to maintain this greenhouse gas stability by limiting methane flux to the atmosphere. We show geochemical evidence for AOM in deep lake sediments and demonstrate that AOM is likely driven by iron (Fe) reduction. Pore-water profiles from Lake Kinneret (Sea of Galilee, Israel) show that this sink for methane is located below the 20-cm depth in the sediment, which is well below the depths at which nitrate and sulfate are completely exhausted, as well as below the zone of methanogenesis. Iron-dependant AOM was verified by Fe(III)-amended mesocosm studies using intact sediment cores, and native iron oxides were detectable throughout the sediments. Because anaerobic Fe(III) respiration is thermodynamically more favorable than both sulfate-dependent methanotrophy and methanogenesis, its occurrence below the zone of methane production supports the idea that reduction of sedimentary iron oxides is kinetically or biologically limited. Similar conditions are likely to prevail in other incompletely pyritized aquatic sediments, indicating that AOM with Fe(III) is an important global sink for methane.},
author = {Sivan, Orit and Adler, Michal and Pearson, Ann and Gelman, Faina and Bar-Or, Itay and John, Seth G. and Eckert, Werner},
doi = {10.4319/lo.2011.56.4.1536},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Sivan, Geochemical evidence for iron-mediated anaerobic oxidation of methane, 2011.pdf:pdf},
isbn = {0024-3590},
issn = {00243590},
journal = {Limnology and Oceanography},
number = {4},
pages = {1536--1544},
title = {{Geochemical evidence for iron-mediated anaerobic oxidation of methane}},
volume = {56},
year = {2011}
}
@article{Bjorneras2017,
author = {Bj{\"{o}}rner{\aa}s, Caroline and Weyhenmeyer, Gesa A. and Evans, Chris D. and Gessner, Mark O. and Grossart, Hans-Peter and Kangur, K{\"{u}}lli and Kokorite, Ilga and Kortelainen, Pirkko and Laudon, Hjalmar and Lehtoranta, Jouni and Lottig, Noah and Monteith, Don T. and N{\~{o}}ges, Peeter and N{\~{o}}ges, Tiina and Oulehle, Filip and Riise, Gunnhild and Rusak, James A. and R{\"{a}}ike, Antti and Sire, Janis and Sterling, Shannon and Kritzberg, Emma S.},
doi = {10.1002/2017GB005749},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Bj{\"{o}}rneras et al.{\%}2c 2017 Widespread increases in Fe concentrations in freshwaters.pdf:pdf},
issn = {08866236},
journal = {Global Biogeochemical Cycles},
keywords = {Browning,Climate change,Freshwaters,Iron,Trends},
pages = {1488--1500},
title = {{Widespread increases in iron concentration in European and North American freshwaters}},
url = {http://doi.wiley.com/10.1002/2017GB005749},
year = {2017}
}
@article{Renz2013,
abstract = {The invasive spionid polychaetes of the genus Marenzelleria spp., consisting of the three sibling species M. neglecta, M. viridis, and M. arctia, has been found in the Baltic Sea since the 1980s. Because of difficulties in species identification, little is known about species-dependent sediment reworking and solute transport. The closely related species are apparently similar in feeding and sediment-dwelling behavior, but size and burrowing depth indicate differences in bioturbation and the biogeochemical consequences thereof. To investigate these potential differences, a tracer experiment with artificial particles (luminophores) and solute tracer (bromide) was conducted. Polychaetes were identified to species level using a molecular genetic key. Modeled results show that all three species display markedly low particle reworking rates with biodiffusion coefficients (Db) of 1.76 cm2 yr21 (M. viridis) and 0.07 cm2 yr21 (M. neglecta) at an abundance of 1273 individuals m22 and 0.44 cm2 yr21 (M. arctia) at twice that abundance. Nonlocal transport coefficients are negligible in all cases. Solute transport by M. neglecta and M. viridis are more similar to one another than to M. arctia, whose solute transport mode is much more diffusive in character (10.9-fold enhanced diffusivity with nonlocal irrigation coefficients [a] of 55.3 yr21) than that of the two other species, which affect tracer distributions in the sediment predominantly through a nonlocal, advective transport mode (a of 108.9 yr21 M. viridis and 130.9 yr21 M. neglecta). Thus, a functional grouping of the sibling species in terms of bioirrigation is not recommended. The},
author = {Renz, Judith R. and Forster, Stefan},
doi = {10.4319/lo.2013.58.6.2046},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Renz, bio turbation Baltic Marenzelleria 2013.pdf:pdf},
issn = {00243590},
journal = {Limnology and Oceanography},
number = {6},
pages = {2046--2058},
title = {{Are similar worms different? A comparative tracer study on bioturbation in the three sibling species Marenzelleria arctia, M. viridis, and M. neglecta from the Baltic Sea}},
volume = {58},
year = {2013}
}
@article{Harley2006,
abstract = {Anthropogenically induced global climate change has profound implications for marine ecosystems and the economic and social systems that depend upon them. The relationship between temperature and individual performance is reasonably well understood, and much climate-related research has focused on potential shifts in distribution and abundance driven directly by temperature. However, recent work has revealed that both abiotic changes and biological responses in the ocean will be substantially more complex. For example, changes in ocean chemistry may be more important than changes in temperature for the performance and survival of many organisms. Ocean circulation, which drives larval transport, will also change, with important consequences for population dynamics. Furthermore, climatic impacts on one or a few 'leverage species' may result in sweeping community-level changes. Finally, synergistic effects between climate and other anthropogenic variables, particularly fishing pressure, will likely exacerbate climate-induced changes. Efforts to manage and conserve living marine systems in the face of climate change will require improvements to the existing predictive framework. Key directions for future research include identifying key demographic transitions that influence population dynamics, predicting changes in the community-level impacts of ecologically dominant species, incorporating populations' ability to evolve (adapt), and understanding the scales over which climate will change and living systems will respond.},
author = {Harley, Christopher D G and Hughes, A. Randall and Hultgren, Kristin M. and Miner, Benjamin G. and Sorte, Cascade J B and Thornber, Carol S. and Rodriguez, Laura F. and Tomanek, Lars and Williams, Susan L.},
doi = {10.1111/j.1461-0248.2005.00871.x},
isbn = {1461-0248},
issn = {1461023X},
journal = {Ecology Letters},
keywords = {Anthropogenic climate change,Carbon dioxide (CO2),Coastal oceanography,Community structure,Distributional shifts,Marine ecosystems,Ocean pH,Population dynamics,Synergistic effects,Temperature},
number = {2},
pages = {228--241},
pmid = {16958887},
title = {{The impacts of climate change in coastal marine systems}},
volume = {9},
year = {2006}
}
@article{Emerson1984,
abstract = {Pore water profiles in shallow estuarine sediments of Puget Sound show the characteristics of enhanced interstitial-water transport by animal activity. Using an in situ 3H experiment and dissolved silicate profiles we evaluate the transport parameter due to animal activity in the surface 20 cm of sediments to be 1-5 × 10-7 s-1 which is in the range of similar parameters determined in other nearshore environments in the U.S. The fluxes of alkalinity, ammonia and silicate across the sediment-water interface due to biological processes are greater than that by one-dimensional molecular diffusion. For the metals Fe, Mn, Cu, Ni and Cd the dominant transport mechanism depends upon the depth at which the metal is released to the pore waters. Probably the most important effect of biological activity on metal remobilization is the removal of sulfide from the pore waters, via ventilation of sediments with oxic overlying water, allowing the enrichment of dissolved metals which might otherwise be very low in concentration due to insoluble sulfide formation. The result is a greatly enhanced flux of metals to the bottom waters.},
author = {Emerson, Steven and Jahnke, Richard and Heggie, David},
doi = {doi:10.1357/002224084788505942},
isbn = {42(1-4), 709-},
issn = {00222402},
journal = {Journal of Marine Research},
number = {3},
pages = {709--730},
title = {{Sediment-water exchange in shallow water estuarine sediments}},
volume = {42},
year = {1984}
}
@article{Ponter1990,
abstract = {Particulate and dissolved Fe and Mn were measured once a week from May to September 1982 in the Kalix River, north Sweden. During winter baseflow the dissolved Fe concentration was 450 ??g l-1. Early snow-melt discharge increased the concentration slightly but during springflood maximum the concentration decreased to a minimum value of 60 ??g l-1 in mid-July. Particulate matter in the Kalix River is dominated by Fe which ranges between 14{\%} and 38{\%} of the ashed suspended load, ??? 70-80{\%} of the total Fe load being retained by 0.45-??m filters. Approximately 10{\%} of particulate Fe can be accounted for by a detrital phase. The particulate Fe/Al ratio showed a mean value of 6.5 which is more than ten times the ratio in mean world river. Particulate Fe showed a peak during early snowmelt and decreased during maximum discharge similar to dissolved Fe. Dissolved Mn concentrations ranged from 1.1 to 53.4 ??m l-1 with a mean value of 11.2 ?? 12.4 ??g l-1, whereas particulate Mn ranged from 3.1 ti 18.2 ??g l-1, with a mean concentration of 10.6 ?? 4.9 ??g l-1. During May and June most Mn was transported in the dissolved phase whereas in July and August the particulate fraction dominated. There was a drastic increase in non-detrital particulate Mn with a concomitant decrease in the dissolved fraction in early July with peak values in mid-July and early August. The decrease in dissolved Mn and increase of particulate Mn is probably the consequence of two processes, namely addition of non-detrital particulate Mn to the river, possibly from lakes, and transformation of dissolved Mn to a particulate phase within the river. A combination of increased pH, temperature and particulate Mn triggered the precipitation of dissolved Mn, although the significance of each factor can not be evaluated from this study. ?? 1990.},
author = {Ponter, Christer and Ingri, Johan and Burman, Jan Ola and Bostrom, Kurt},
doi = {10.1016/0009-2541(90)90042-6},
isbn = {0009-2541},
issn = {00092541},
journal = {Chemical Geology},
number = {1-2},
pages = {121--131},
title = {{Temporal variations in dissolved and suspended iron and manganese in the Kalix River, northern Sweden}},
volume = {81},
year = {1990}
}
@article{Laudon2011,
abstract = {We bring together three decades of research from a boreal catchment to facilitate an improved mecha- nistic understanding of surface water dissolved or- ganic carbon(DOC) regulation acrossmultiple scales. The Krycklan Catchment Study encompasses 15 monitored nested research catchments, ranging from 3 to 6900 ha in size, as well as a set of monitored transects of forested and wetland soils.We showthat in small homogenous catchments, hydrological functioning provides a first order control on the temporal variability of stream water DOC. In larger, more heterogeneous catchments, stream water DOC dynamics are regulated by the combined effect of hydrological mechanisms and the proportion of ma- jor landscape elements, such aswetland and forested areas.Asa consequence, streams withheterogeneous catchments undergo a temporal switch in the DOC source. In a typical boreal catchment covered by 10-20{\%} wetlands, DOC originates predominantly from wetland sources during low flow conditions. During high flow, the major source of DOC is from forested areas of the catchment.Wedemonstrate that by connecting knowledge about DOC sources in the landscape with detailed hydrological process under- standing, animprovedrepresentationof streamwater DOC regulation can be provided. The purpose of this study is to serve as a framework for appreciating the role of regulating mechanisms, connectivity and scalingforunderstandingthepatternanddynamicsof surface water DOC across complex landscapes. The results from this study suggest that the sensitivity of streamwaterDOC in the boreal landscape ultimately depends on changes within individual landscape elements, the proportion and connectivity of these affected landscape elements, and how these changes are propagated downstream.},
archivePrefix = {arXiv},
arxivId = {arXiv:1011.1669v3},
author = {Laudon, Hjalmar and Berggren, Martin and Agren, Anneli and Buffam, Ishi and Bishop, Kevin and Grabs, Thomas and Jansson, Mats and Kohler, Stephan},
doi = {10.1007/s10021-011-9452-8},
eprint = {arXiv:1011.1669v3},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Laudon, patterns and dynamics of DOC, 2011.pdf:pdf},
isbn = {1432-9840$\backslash$n1435-0629},
issn = {14329840},
journal = {Ecosystems},
keywords = {Krycklan catchment,boreal forest,connectivity,dissolved organic carbon,hydrology,scaling},
number = {6},
pages = {880--893},
pmid = {264460600012},
title = {{Patterns and Dynamics of Dissolved Organic Carbon (DOC) in Boreal Streams: The Role of Processes, Connectivity, and Scaling}},
volume = {14},
year = {2011}
}
@article{Kuma1996,
abstract = {Iron solubilities of Fe(III) hydroxide in coastal and oceanic waters and$\backslash$nin the ultraviolet (UV)-irradiated seawaters over a pH range of 5.7-8.2$\backslash$nat 20 degrees C were determined by a simple filtration (0.025 mu m)$\backslash$ninvolving gamma-activity measurement of Fe-59. At pH ranges of 5.7-7.2$\backslash$n(coastal water) and of 5.7-7.6 (oceanic water), only the Fe(OH)(2)(+)$\backslash$nspecies is significant. The calculated solubility products, log{\{}*{\}}K-SO,$\backslash$nfor coastal and oceanic waters were 4.8-5.0 and 4.4-4.6, respectively.$\backslash$nThe solubilities within the pH range of 7.8-8.2 are relatively$\backslash$nindependent of pH and aging time. Solubility in the oceanic water was$\backslash$nabout one order of magnitude lower than that in the coastal water, and$\backslash$nUV irradiation reduced solubility to less than or equal to 0.1 nM. The$\backslash$nvertical profiles of ambient Fe(III) solubility (pH 8.0-8.2) in oceanic$\backslash$nwaters have the following features in common: solubility in the surface$\backslash$nmixed layer is high and variable (0.3-0.6 nM), generally corresponding$\backslash$nwith the depth of high chlorophyll a concentrations; solubility minima$\backslash$n(0.15-0.2 nM) occur at a depth of 50-200 m. These results suggest that$\backslash$nnatural organic Fe(III) chelators exist in significant concentrations$\backslash$nand control the dissolved iron concentration in seawaters.},
archivePrefix = {arXiv},
arxivId = {Limnol.Oceanogr., 41(3), 1996, 396-407},
author = {Kuma, Kenshi and Nishioka, Jun and Matsunaga, Katsuhiko},
doi = {10.4319/lo.1996.41.3.0396},
eprint = {Limnol.Oceanogr., 41(3), 1996, 396-407},
isbn = {0024-3590},
issn = {0024-3590},
journal = {Limnology and Oceanography},
number = {3},
pages = {396--407},
title = {{Controls on iron(III) hydroxide solubility in seawater: The influence of pH and natural organic chelators}},
volume = {41},
year = {1996}
}
@article{Kraal2012,
abstract = {In this study, we investigate phosphorus (P) and iron (Fe) cycling in sediments along a depth transect from within to well below the oxygen minimum zone (OMZ) in the northern Arabian Sea (Murray Ridge). Pore-water and solid-phase analyses show that authigenic formation of calcium phosphate minerals (Ca-P) is largely restricted to where the OMZ intersects the seafloor topography, likely due to higher depositional fluxes of reactive P. Nonetheless, increased ratios of organic carbon to organic P (C-org/P-org) and to total reactive P (C-org/P-reactive) in surface sediments indicate that the overall burial efficiency of P relative to C-org decreases under the low bottom water oxygen concentrations (BWO) in the OMZ. The relatively constant Fe/Al ratio in surface sediments along the depth transect suggest that corresponding changes in Fe burial are limited. Sedimentary pyrite contents are low throughout the similar to 25 cm sediment cores at most stations, as commonly observed in the Arabian Sea OMZ. However, pyrite is an important sink for reactive Fe at one station in the OMZ. A reactive transport model (RTM) was applied to quantitatively investigate P and Fe diagenesis at an intermediate station at the lower boundary of the OMZ (bottom water O-2: similar to 14 mu mol L-1). The RTM results contrast with earlier findings in showing that Fe redox cycling can control authigenic apatite formation and P burial in Arabian Sea sediment. In addition, results suggest that a large fraction of the sedimentary Ca-P is not authigenic, but is instead deposited from the water column and buried. Dust is likely a major source of this Ca-P. Inclusion of the unreactive Ca-P pool in the C-org/P ratio leads to an overestimation of the burial efficiency of reactive P relative to C-org along the depth transect. Moreover, the unreactive Ca-P accounts for similar to 85{\%} of total Ca-P burial. In general, our results reveal large differences in P and Fe chemistry between stations in the OMZ, indicating dynamic sedimentary conditions under these oxygen-depleted waters.},
author = {Kraal, P. and Slomp, C. P. and Reed, D. C. and Reichart, G. J. and Poulton, S. W.},
doi = {10.5194/bg-9-2603-2012},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Kraal, Sedimentary phosphorus and iron cycling in and below the oxygen, 2012.pdf:pdf},
isbn = {1726-4170},
issn = {17264170},
journal = {Biogeosciences},
number = {7},
pages = {2603--2624},
title = {{Sedimentary phosphorus and iron cycling in and below the oxygen minimum zone of the northern Arabian Sea}},
volume = {9},
year = {2012}
}
@article{moore2013,
abstract = {Nature Geoscience 6, 701 (2013). doi:10.1038/ngeo1765},
author = {Moore, C M and Mills, M M and Arrigo, K R and Berman-Frank, I and Bopp, L and Boyd, P W and Galbraith, E D and Geider, R J and Guieu, C and Jaccard, S L and Jickells, T D and Roche, J L and Lenton, T M and Mahowald, N M and Mara{\~{n}}{\'{o}}n, E and Marinov, I and Moore, J K and Nakatsuka, T and Oschlies, A and Saito, M a and Thingstad, T F and Tsuda, A and Ulloa, O},
doi = {10.1038/ngeo1765},
file = {:C$\backslash$:/Users/Wytse Lenstra/AppData/Local/Mendeley Ltd./Mendeley Desktop/Downloaded/Moore et al. - 2013 - Processes and patterns of oceanic nutrient limitation.pdf:pdf},
isbn = {1752-0894},
issn = {1752-0894},
journal = {Nature Publishing Group},
number = {9},
pages = {701--710},
publisher = {Nature Publishing Group},
title = {{Processes and patterns of oceanic nutrient limitation}},
url = {http://dx.doi.org/10.1038/ngeo1765{\%}5Cnpapers://dee23da0-e34b-4588-b624-f878b46d7b3d/Paper/p935},
volume = {6},
year = {2013}
}
@article{Steenbergh2011a,
abstract = {The relationship between phosphatase activity and the element limiting microbial activity (carbon [C], nitrogen [N], or phosphorus [P]) was studied experimentally in sediment from four stations in the Baltic Sea located along a depth transect from oxic to anoxic bottom waters. The role of extracellular phosphatases was assessed by determining the percentages of intact cells that could be labeled with an artificial substrate for phosphatases (i.e., enzyme-labeled fluorescence 97 phosphatase substrate [ELF]) using a flow cytometer. Phosphatase activity was detected in sediment slurries from all sites either with or without prior incubation under oxic or anoxic conditions. In addition, ELF-labeled cells were detected in all incubated sediments, indicating that intact cells bearing phosphatases contribute to the phosphatase activity. Phosphatase activities and percentages of ELF-labeled cells were lower for the anoxic than for the oxic slurry incubations. Phosphatases are likely used to relieve the limitation of microbial activity by utilizable C in these recently deposited, organic C–rich sediments in the Baltic Sea. In marine sediments overlain by anoxic bottom waters, the biological and chemical mechanisms of P retention are often less efficient than in oxic settings and the P released to relieve C limitation escapes to the overlying water. This explains the ongoing higher P fluxes from sediments overlain by anoxic bottom waters.},
author = {Steenbergh, Anne K. and Bodelier, Paul L. E. and Hoogveld, Hans L. and Slomp, Caroline P. and Laanbroek, Hendrikus J.},
doi = {10.4319/lo.2011.56.6.2018},
isbn = {0024-3590},
issn = {00243590},
journal = {Limnology and Oceanography},
number = {6},
pages = {2018--2026},
title = {{Phosphatases relieve carbon limitation of microbial activity in Baltic Sea sediments along a redox-gradient}},
url = {http://doi.wiley.com/10.4319/lo.2011.56.6.2018},
volume = {56},
year = {2011}
}
@article{Meier2006,
abstract = {As the uncertainty of projected precipitation and wind changes in$\backslash$nregional climate change scenario simulations over Europe for the$\backslash$nlate 21st century is large, we applied a multi-model ensemble approach$\backslash$nusing 16 scenario simulations based upon seven regional models, five$\backslash$nglobal models, and two emission scenarios to gain confidence in projected$\backslash$nsalinity changes in the Baltic Sea. In the dynamical downscaling$\backslash$napproach a regional ocean circulation model and a large-scale hydrological$\backslash$nmodel for the entire Baltic Sea catchment area were used. Despite$\backslash$nthe uncertainties, mainly caused by global model biases, salinity$\backslash$nchanges in all projections are either negative or not statistically$\backslash$nsignificant in terms of natural variability.},
author = {Meier, H. E Markus and Kjellstr{\"{o}}m, Erik and Graham, L. Phil},
doi = {10.1029/2006GL026488},
file = {:C$\backslash$:/Users/Wytse Lenstra/AppData/Local/Mendeley Ltd./Mendeley Desktop/Downloaded/Meier, Kjellstr{\"{o}}m, Graham - 2006 - Estimating uncertainties of projected Baltic Sea salinity in the late 21st century.pdf:pdf},
isbn = {0094-8276},
issn = {00948276},
journal = {Geophysical Research Letters},
number = {15},
pages = {1--4},
title = {{Estimating uncertainties of projected Baltic Sea salinity in the late 21st century}},
volume = {33},
year = {2006}
}
@article{Caraco1989,
abstract = {Sediments of aquatic systems play a critical part in controlling phosphorus loading to the water column. Because P loading is an important determinant of productivity in aquatic systems, there has been keen interest in variables that influence P release from sediments. In disagreement with present theories our data from 23 different aquatic systems indicate that sulphate concentration of waters is an extremely important variable controlling P release from sediments. The increased P release from sediments at higher sulphate concentrations may help to explain why primary productivity in freshwater systems (with relatively low sulphate concentrations) tends to be P limited, whereas in many saline systems (with high sulphate concentrations) production i soften P sufficient. Further, our results indicate that anthropogenically induced changes from atmospheric S inputs could, over time, alter the P cycle of aquatic systems.},
archivePrefix = {arXiv},
arxivId = {nature.vol.342.30nov1989},
author = {Caraco, N F and Cole, J J and Likens, G E},
doi = {10.1038/341316a0},
eprint = {nature.vol.342.30nov1989},
isbn = {0028-0836},
issn = {0028-0836},
journal = {Nature},
keywords = {1-field monitoring,1-review,2-lakewater,3-internal phosphorus loading,4-sulfur,6-Canada},
number = {6240},
pages = {316--318},
pmid = {2507922},
title = {{Evidence for sulphate-controlled phosphorus release from sediments of aquatic systems}},
url = {http://www.nature.com/doifinder/10.1038/341316a0},
volume = {341},
year = {1989}
}
@article{Stockenberg1997,
abstract = {Denitrification was measured over an 8-month period in the Bothnian Bay and the Bothnian Sea, the two northernmost basins of the Baltic Sea. The recorded rates varied between 0 and 0.94 mmol N m(-2) day(-1). In the Bothnian Sea, a seasonal pattern could be discerned with high rates in spring, no rate in summer and a moderate rate in winter. In the Bothnian Bay, no such seasonality was observed. It is suggested that denitrification in the Gulf of Bothnia is regulated by sediment nitrification. Calculation of annual mean rates of denitrification gave that the amount of nitrogen consumed by denitrification corresponded to 1.45 x 10(4) tons N year(-1) for the Bothnian Bay and 3.45 x 10(4) tons N year(-1) for the Bothnian Sea. A comparison with total N input (river runoff, point sources and atmospheric deposition) to the two basins showed that the proportion of N removed through denitrification amounted to 23{\%} for the Bothnian Bay and 31{\%} for the Bothnian Sea. (C) 1997 Academic Press Limited.},
author = {Stockenberg, a and Johnstone, R W},
doi = {DOI 10.1006/ecss.1997.0271},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Stockenberg, Benthic Denitrification in the Gulf of Bothnia, 1997.pdf:pdf},
isbn = {0272-7714},
issn = {02727714},
journal = {Marine Ecology Progress Series},
keywords = {baltic sea,denitrification,gulf of bothnia,nitrogen cycling},
number = {February 1996},
pages = {835--843},
title = {{Benthic Denitrification in the Gulf of Bothnia}},
year = {1997}
}
@article{Slomp2013,
abstract = {Studies of phosphorus (P) dynamics in surface sediments of lakes and coastal seas typically emphasize the role of coupled iron (Fe), sulfur (S) and P cycling for sediment P burial and release. Here, we show that anaerobic oxidation of methane (AOM) also may impact sediment P cycling in such systems. Using porewater and sediment profiles for sites in an oligotrophic coastal basin (Bothnian Sea), we provide evidence for the formation of Fe-bound P (possibly vivianite; Fe3(PO4)2({\textperiodcentered})8H2O) below the zone of AOM with sulfate. Here, dissolved Fe(2+) released from oxides is no longer scavenged by sulfide and high concentrations of both dissolved Fe(2+) ({\textgreater}1 mM) and PO4 in the porewater allow supersaturation with respect to vivianite to be reached. Besides formation of Fe(II)-P, preservation of Fe-oxide bound P likely also contributes to permanent burial of P in Bothnian Sea sediments. Preliminary budget calculations suggest that the burial of Fe-bound P allows these sediments to act as a major sink for P from the adjacent eutrophic Baltic Proper.},
author = {Slomp, Caroline P. and Mort, Haydon P. and Jilbert, Tom and Reed, Daniel C. and Gustafsson, Bo G. and Wolthers, Mariette},
doi = {10.1371/journal.pone.0062386},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Proposal papers/Slomp, Coupled dynamics of iron and phosphorus in sediments, anaeriboc oxidation of methane (Fe and Methane).pdf:pdf},
issn = {19326203},
journal = {PLoS ONE},
number = {4},
pmid = {23626815},
title = {{Coupled dynamics of iron and phosphorus in sediments of an oligotrophic coastal basin and the impact of anaerobic oxidation of methane}},
volume = {8},
year = {2013}
}
@article{Capet2016,
abstract = {We show that from 1955 to 2013, the inventory of oxygen in the Black Sea has decreased by 36 {\%} and the basin-averaged oxygen penetration depth has decreased from 140 m in 1955 to 90 m in 2013, which is the shallowest annual value recorded during that period. The oxygenated Black Sea surface layer separates the world's largest reservoir of toxic hydrogen sulphide from the atmosphere. The threat of chemocline excursion events led to hot debates in the past decades arguing on the vertical stability of the Black Sea oxic/suboxic interface. In the 1970s and 1980s the Black Sea faced severe eutrophication. Enhanced respiration rates reduced the thickness of the oxygenated layer. The consecutive increase of oxygen inventory in 1985–1995 supported arguments in favor of the stability of the oxic layer. Concomitant with a reduction of nutrient loads, this increase also supported the perception of a Black Sea recovering from eutrophication. More recently, atmospheric warming was shown to reduce the ventilation of the lower oxic layer by lowering Cold Intermediate Layer (CIL) formation rates. The debate on the vertical migration of the oxic interface also addressed the natural spatial variability affecting Black Sea properties when expressed in terms of depth. Here we show that using isopycnal coordinates does not free from a significant spatial variability of oxygen penetration depths. Considering this spatial variability, the analysis of a composite historical set of oxygen profiles evidenced a significant shoaling of the oxic layer, and showed that the transient "recovery" of the 1990s was mainly a result of increased CIL formation rates during that period. As both atmospheric warming and eutrophication are expected to increase in the near future, monitoring the dynamics of the Black Sea oxic layer is required to assess the threat of further shoaling.},
author = {Capet, Arthur and Stanev, Emil V. and Beckers, Jean Marie and Murray, James W. and Gr{\'{e}}goire, Marilaure},
doi = {10.5194/bg-13-1287-2016},
file = {:C$\backslash$:/Users/Wytse Lenstra/Downloads/bg-13-1287-2016{\%}281{\%}29.pdf:pdf},
isbn = {1726-4170},
issn = {17264189},
journal = {Biogeosciences},
number = {4},
pages = {1287--1297},
title = {{Decline of the Black Sea oxygen inventory}},
volume = {13},
year = {2016}
}
@article{Ingall1997,
abstract = {Organic carbon oxidation and benthic total phosphorus flux measurements from sites covering a range of bottom-water oxygen concentrations have been compiled. The data show that P regeneration relative to carbon oxidation is much more extensive in sediments overlain by oxygen-depleted waters. These results are consistent with studies showing that low oxygen bottom-water concentrations correlate with reduced total phosphorus burial efficiencies and enhanced organic carbon burial efficiencies. Based on these observations a positive feedback is proposed between water-column anoxia, enhanced benthic phosphorus regeneration, and marine productivity. This feedback may help explain the widespread accumulation of organic-rich marine sediments from anoxic waters observed in the geologic record.},
author = {Ingall, Ellery and Jahnke, Richard},
doi = {10.1016/S0025-3227(96)00112-0},
isbn = {0025-3227},
issn = {00253227},
journal = {Marine Geology},
number = {1-4},
pages = {219--229},
pmid = {23218245},
title = {{Influence of water-column anoxia on the elemental fractionation of carbon and phosphorus during sediment diagenesis}},
volume = {139},
year = {1997}
}
@incollection{Ruttenberg2003,
abstract = {Phosphorus is an essential nutrient for all life-forms. It is a key player in fundamental biochemical reactions involving genetic material (DNA and RNA) and energy transfer (ATP) and in structural support of organisms provided by membranes (phospholipids) and bone (the biomineral hydroxyapatite). Photosynthetic organisms utilize dissolved phosphorus, carbon, and other essential nutrients to build their tissues using energy from the sun. Biological productivity is contingent upon the availability of phosphorus to these simple organisms that constitute the base of the food web in both terrestrial and aquatic systems. It begins with a brief overview of the various components of the global phosphorus cycle. Estimates of the mass of important phosphorus reservoirs, transport rates (fluxes) between reservoirs. Following the overview, various aspects of the global phosphorus cycle are examined in more depth, including a discussion of the most pressing research questions currently being posed and research efforts presently underway to address these questions. ?? 2014 Elsevier Ltd. All rights reserved.},
author = {Ruttenberg, K. C.},
booktitle = {Treatise on Geochemistry: Second Edition},
doi = {10.1016/B978-0-08-095975-7.00813-5},
isbn = {9780080983004},
issn = {1529-6466},
keywords = {Biogeochemistry,Cycling,Global P cycle},
pages = {499--558},
pmid = {24388},
title = {{The Global Phosphorus Cycle}},
volume = {10},
year = {2003}
}
@article{Gunnars2002,
abstract = {The formation of Fe(III) oxyhydroxide colloids by oxidation of Fe(II) and their subsequent aggregation to larger particles were studied in laboratory experiments with natural water from a freshwater lake and a brackish coastal sea. Phosphate was incorporated in the solid phase during the course of hydrolysis of iron. The resulting precipitated amorphous Fe(III) oxyhydroxide phases were of varying composition, depending primarily on the initial dissolved Fe/P molar ratio, but with little influence by salinity or concentration of calcium ions. The lower limiting Fe/P ratio found for the solid phase suggests the formation of a basic Fe(III) phosphate compound with a stoichiometric Fe/P ratio of close to two. This implies that an Fe/P stoichiometry of ≈2 ultimately limits the capacity of precipitating Fe(III) to fix dissolved phosphate at oxic/anoxic boundaries in natural waters. In contrast to phosphorus, the uptake of calcium seemed to be controlled by sorption processes at the surface of the iron-rich particles formed. This uptake was more efficient in freshwater than in brackish water, suggesting that salinity restrains the uptake of calcium by newly formed Fe(III) oxyhydroxides in natural waters. Moreover, salinity enhanced the aggregation rate of the colloids formed. The suspensions were stabilised by the presence of organic matter, although this effect was less pronounced in seawater than in freshwater. Thus, in seawater of 6 to 33 ‰S, the removal of particles was fast (removal half time {\textless} 200 h), whereas the colloidal suspensions formed in freshwater were stable (removal half time {\textgreater} 900 h). Overall, oxidation of Fe(II) and removal of Fe(III) oxyhydroxide particles were much faster in seawater than in freshwater. This more rapid turnover results in lower iron availability in coastal seawater than in freshwater, making iron more likely to become a limiting element for chemical scavenging and biologic production. Copyright {\textcopyright} 2002 Elsevier Science Ltd.},
author = {Gunnars, Anneli and Blomqvist, Sven and Johansson, Peter and Andersson, Christian},
doi = {10.1016/S0016-7037(01)00818-3},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
number = {5},
pages = {745--758},
title = {{Formation of Fe(III) oxyhydroxide colloids in freshwater and brackish seawater, with incorporation of phosphate and calcium}},
volume = {66},
year = {2002}
}
@article{Marz2008,
abstract = {The Zambezi deep-sea fan, the largest of its kind along the east African continental margin, is poorly studied to date, despite its potential to record marine and terrestrial climate signals in the southwest Indian Ocean. Therefore, gravity core GeoB 9309-1, retrieved from 1219 m water depth, was investigated for various geophysical (magnetic susceptibility, porosity, colour reflectance) and geochemical (pore water and sediment geochemistry, Fe and P speciation) properties. Onboard and onshore data documented a sulphate/methane transition (SMT) zone at {\~{}} 450-530 cm sediment depth, where the simultaneous consumption of pore water sulphate and methane liberates hydrogen sulphide and bi-carbonate into the pore space. This leads to characteristic changes in the sediment and pore water chemistry, as the reduction of primary Fe (oxyhydr)oxides, the precipitation of Fe sulphides, and the mobilization of Fe (oxyhydr)oxide-bound P. These chemical processes also lead to a marked decrease in magnetic susceptibility. Below the SMT, we find a reduction of porosity, possibly due to pore space cementation by authigenic minerals. Formation of the observed geochemical, magnetic and mineralogical patterns requires a fixation of the SMT at this distinct sediment depth for a considerable time-which we calculated to be {\~{}} 10 000 years assuming steady-state conditions-following a period of rapid upward migration towards this interval. We postulate that the worldwide sea-level rise at the last glacial/interglacial transition ({\~{}} 10 000 years B.P.) most probably caused the fixation of the SMT at its present position, through drastically reduced sediment delivery to the deep-sea fan. In addition, we report an internal redistribution of P occurring around the SMT, closely linked to the (de)coupling of sedimentary Fe and P, and leaving a characteristic pattern in the solid P record. By phosphate re-adsorption onto Fe (oxyhydr)oxides above, and formation of authigenic P minerals (e.g. vivianite) below the SMT, deep-sea fan deposits may potentially act as long-term sinks for P. {\textcopyright} 2008 Elsevier B.V. All rights reserved.},
author = {M{\"{a}}rz, C. and Hoffmann, J. and Bleil, U. and de Lange, G. J. and Kasten, S.},
doi = {10.1016/j.margeo.2008.05.013},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Marz, Diagenetic changes of magnetic and geochemical signals by anaerobic methane, 2008.pdf:pdf},
isbn = {0025-3227},
issn = {00253227},
journal = {Marine Geology},
keywords = {Anaerobic oxidation of methane,Deep-sea fan,Early diagenesis,Fe,P,Susceptibility},
number = {3-4},
pages = {118--130},
publisher = {Elsevier B.V.},
title = {{Diagenetic changes of magnetic and geochemical signals by anaerobic methane oxidation in sediments of the Zambezi deep-sea fan (SW Indian Ocean)}},
url = {http://dx.doi.org/10.1016/j.margeo.2008.05.013},
volume = {255},
year = {2008}
}
@article{Middelburg1989,
abstract = {A model is presented for the decomposition of organic matter in marine sediments. The model considers the organic matter as a whole. In this model the first-order rate parameters (k) gradually decrease with time (t) according to log k = -0.95 log t - 0.81 (N= 140; r = 0.987). This equation is found to be valid over eight orders of magnitude and is based on organic carbon versus depth profiles of well-dated cores and laboratory experiments. The predicted continuous decrease in the reactivity of organic matter is consistent with multi-G models and in situ measurements of sulphate reduction. Although all organic carbon versus depth profiles follow the same reactivity decrease with time, their reactivity at the sediment-water interface (i.e., "apparent initial age") is different. Apparent initial ages calculated on the basis of various experiments and field measurements show consistent trends. {\textcopyright} 1989.},
author = {Middelburg, Jack J.},
doi = {10.1016/0016-7037(89)90239-1},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Middelburg,A simple rate model for organic matter decomposition in marine sediments,1989.pdf:pdf},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
number = {7},
pages = {1577--1581},
pmid = {4172},
title = {{A simple rate model for organic matter decomposition in marine sediments}},
volume = {53},
year = {1989}
}
@article{Poulton2005,
abstract = {The development of a sequential extraction procedure for iron in modern and ancient sediments is presented. The scheme recognizes seven operationally derived iron pools: (1) carbonate associated Fe (Fecarb), including siderite and ankerite; (2) easily reducible oxides (Feox1), including ferrihydrite and lepidocrocite; (3) reducible oxides (Feox2), including goethite, hematite and akagan??ite; (4) magnetite (Femag); (5) poorly reactive sheet silicate Fe (FePRS); (6) pyrite Fe (Fepy); and (7) unreactive silicate Fe (FeU). As such, this is the first extraction scheme specifically developed to allow the separate identification of magnetite, and the first to allow a complete evaluation of Fe carbonate phases such as siderite and ankerite. The scheme was developed following tests on pure mineral phases to evaluate the minerals solubilized by each technique and to determine optimum extraction times. Further tests on mixtures of pure minerals and on grain-size separated sediments from two major US rivers and two glacial meltwaters validate the specificity of the scheme for different pools of iron minerals, and demonstrate a high degree of reproducibility for each analytical stage. The data obtained for the riverine and glacial sediments are additionally discussed in relation to the dominant modes of transport of different iron minerals in fine-grained continental sediments. ?? 2004 Elsevier B.V. All rights reserved.},
author = {Poulton, Simon W. and Canfield, Donald E.},
doi = {10.1016/j.chemgeo.2004.09.003},
file = {:C$\backslash$:/Users/Wytse Lenstra/AppData/Local/Mendeley Ltd./Mendeley Desktop/Downloaded/Poulton, Canfield - 2005 - Development of a sequential extraction procedure for iron Implications for iron partitioning in continentally.pdf:pdf},
isbn = {0009-2541},
issn = {00092541},
journal = {Chemical Geology},
keywords = {Extraction,Glacial sediments,Iron,Magnetite,River particulates,Siderite},
number = {3-4},
pages = {209--221},
pmid = {17},
title = {{Development of a sequential extraction procedure for iron: Implications for iron partitioning in continentally derived particulates}},
volume = {214},
year = {2005}
}
@article{Tyrrell1999,
abstract = {A simple model has the potential to resolve the long-running debate amongst oceanographers over whether nitrogen or phosphorus exerts overall control on oceanic primary production. A representation of the competition between nitrogen-fixing and other phytoplankton is inserted into a two-box global model of the oceanic nitrogen and phosphorus cycles. Homeostatic regulation of both nitrate and phosphate concentrations results, with surface waters more deficient in nitrate than phosphate in the steady state, but with external phosphate inputs controlling longer-term primary production in the global ocean.},
author = {Tyrrell, Toby},
doi = {10.1038/22941},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Tyrell, the relative influence of nitrogen and phosphorus on oceanic primary production, 1999.pdf:pdf},
isbn = {0028-0836},
issn = {00280836},
journal = {Nature},
keywords = {GC Oceanography,QH301 Biology},
number = {6744},
pages = {525--531},
pmid = {310},
title = {{The relative influences of nitrogen and phosohorus on oceanic primary production}},
url = {http://www.nature.com/nature/journal/v400/n6744/full/400525a0.html{\%}5Cnhttp://www.nature.com/doifinder/10.1038/22941},
volume = {400},
year = {1999}
}
@article{Jilbert2013a,
abstract = {Microanalysis of epoxy resin-embedded sediments is used to demonstrate the presence of authigenic iron (Fe) (II) phosphates and manganese (Mn)-calcium (Ca)-carbonate-phosphates in the deep euxinic basins of the Baltic Sea. These minerals constitute major burial phases of phosphorus (P) in this area, elevating the total P burial rate above that expected for a euxinic depositional environment. Particle shuttles of Fe and Mn oxides into the deep euxinic basins act as drivers for P-bearing mineral authigenesis. While Fe(II) phosphates are formed continuously in the upper sediments following the sulfidization of Fe-oxyhydroxides and release of associated P, Mn-Ca-carbonate-phosphates are formed intermittently following inflow events of oxygenated North Sea water into the deep basins. The mechanism of Fe(II) phosphate formation differs from previously reported occurrences of vivianite formation in marine sediments, by occurring within, rather than below, the sulfate-methane transition zone. The spatial distribution of both authigenic phases in Baltic sediments varies in accordance with the periodic expansion of anoxia on centennial to millennial timescales. The results highlight the potential importance of authigenic P-bearing minerals other than carbonate fluorapatite for total P burial in euxinic basins. ?? 2013 Elsevier Ltd.},
author = {Jilbert, Tom and Slomp, Caroline P.},
doi = {10.1016/j.gca.2013.01.005},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
pages = {155--169},
title = {{Iron and manganese shuttles control the formation of authigenic phosphorus minerals in the euxinic basins of the Baltic Sea}},
volume = {107},
year = {2013}
}
@article{Burton2008,
abstract = {A new chromium-reducible sulfur (CRS) method suitable for the quantification of reduced inorganic S (RIS) in acid-sulfate soils is presented. The new method utilises the reduction of RIS by an acidic Cr(II) solution within a sealed reaction chamber and diffusion of the produced H2S(g) into an alkaline Zn solution. It offers rapid sample processing times, without the need for large volumes of high-purity N2(g) or for specialized, expensive glassware. Examination of pyrite-talc mixtures containing up to 11.8{\%} pyrite, revealed that the method achieves 95-98{\%} recovery of RIS. A comparison between CRS measured by the new diffusion-based method and that measured by a standard purge-and-trap method for 25 pyritic soil samples shows a very strong (r2 = 0.996) linear relationship with a slope of 0.995. The ability of the new diffusion-based CRS method to achieve accurate and precise quantification of RIS in acid-sulfate soils is demonstrated. ?? 2008 Elsevier Ltd. All rights reserved.},
author = {Burton, Edward D. and Sullivan, Leigh A. and Bush, Richard T. and Johnston, Scott G. and Keene, Annabelle F.},
doi = {10.1016/j.apgeochem.2008.07.007},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Methods/Extractions/Sulfur/Burton, S extraction.pdf:pdf},
isbn = {0883-2927},
issn = {08832927},
journal = {Applied Geochemistry},
number = {9},
pages = {2759--2766},
title = {{A simple and inexpensive chromium-reducible sulfur method for acid-sulfate soils}},
volume = {23},
year = {2008}
}
@article{Graham2004,
abstract = {River flow to the Baltic Sea originates under a range of different climate regimes in a drainage basin covering some 1 600 000 km2 Changes to the climate in the Baltic Basin will not only affect the total amount of freshwater flowing into the sea, but also the distribution of the origin of these flows. Using hydrological modeling, the effects of future climate change on river runoff to the Baltic Sea have been analyzed. Four different climate change scenarios from the Swedish Regional Climate Modelling Programme (SWE-CLIM) were used. The resulting change to total mean annual river flow to the Baltic Sea ranges from -2{\%} to +15{\%} of present-day flow according to the different climate scenarios. The magnitude of changes within different subregions of the basin varies considerably, with the most severe mean annual changes ranging from -30{\%} to +40{\%}. However, common to all of the scenarios evaluated is a general trend of reduced river flow from the south of the Baltic Basin together with increased river flow from the north.},
author = {Graham, L. Phil},
doi = {10.1639/0044-7447(2004)033},
isbn = {0044-7447},
issn = {0044-7447},
journal = {AMBIO: A Journal of the Human Environment},
number = {4},
pages = {235--241},
pmid = {15264602},
title = {{Climate change effects on river flow to the Baltic Sea}},
volume = {33},
year = {2004}
}
@article{Krachler2016,
abstract = {Iron is a micronutrient of particular interest as low levels of iron limit primary production of phytoplankton and carbon fluxes in extended regions of the world's oceans. Sphagnum-peatland runoff is extraordinarily rich in dissolved humic-bound iron. Given that several of the world's largest wetlands are Sphagnum-dominated peatlands, this ecosystem type may serve as one of the major sources of iron to the ocean. Here, we studied five near-coastal creeks in North Scotland using freshwater/seawater mixing experiments of natural creek water and synthetic seawater based on a 59Fe radiotracer technique combined with isotopic characterization of dissolved organic carbon by Accelerator Mass Spectrometry. Three of the creeks meander through healthy Sphagnum-dominated peat bogs and the two others through modified peatlands which have been subject to artificial drainage for centuries. The results revealed that, at the time of sampling (August 16-24, 2014), the creeks that run through modified peatlands delivered 11-15 $\mu$g iron per liter creek water to seawater, whereas the creeks that run through intact peatlands delivered 350-470 $\mu$g iron per liter creek water to seawater. To find out whether this humic-bound iron is bio-available to marine algae, we performed algal growth tests using the unicellular flagellated marine prymnesiophyte Diacronema lutheri and the unicellular marine green alga Chlorella salina, respectively. In both cases, the riverine humic material provided a highly bio-available source of iron to the marine algae. These results add a new item to the list of ecosystem services of Sphagnum-peatlands.},
author = {Krachler, Regina and Krachler, Rudolf F. and Wallner, Gabriele and Steier, Peter and {El Abiead}, Yasin and Wiesinger, Hubert and Jirsa, Franz and Keppler, Bernhard K.},
doi = {10.1016/j.scitotenv.2016.03.012},
issn = {18791026},
journal = {Science of the Total Environment},
keywords = {Aquatic humic substances,Biogeochemistry of iron,Ecosystem services,Iron bioavailability,Seawater,Sphagnum peatlands},
pages = {53--62},
title = {{Sphagnum-dominated bog systems are highly effective yet variable sources of bio-available iron to marine waters}},
volume = {556},
year = {2016}
}
@article{Ingri2006,
abstract = {Temporal variations in the iron isotopic composition, ??56Fe between -??0.13??? and 0.31???, have been measured in the suspended fraction in a Boreal river. The major mechanism behind these variations is temporal mixing between two types of particles-colloids, Fe-oxyhydroxides and Fe-C colloids. Data in this study indicate that these two types of colloids have different Fe-isotope composition. The Fe-C colloid has a negative ??56Fe value whereas the Fe-oxyhydroxide colloid is enriched in 56Fe. These two types of colloidal matter have different hydrogeochemical origin. The Fe-C colloid reaches the river during storm events when the upper sections of the soil profile (O and E horizons) are flooded by a rising water table. Colloidal Fe-oxyhydroxides reach the river via inflow and subsequent oxidation of groundwater enriched in dissolved Fe(II). ?? 2006.},
author = {Ingri, Johan and Malinovsky, Dmitry and Rodushkin, Ilia and Baxter, Douglas C. and Widerlund, Anders and Andersson, Per and Gustafsson, Orjan and Forsling, Willis and Ohlander, Bjorn},
doi = {10.1016/j.epsl.2006.03.031},
isbn = {0012821X},
issn = {0012821X},
journal = {Earth and Planetary Science Letters},
keywords = {Fe isotopes,Fe-colloids,Kalix River,suspended matter,temporal variation},
number = {3-4},
pages = {792--798},
title = {{Iron isotope fractionation in river colloidal matter}},
volume = {245},
year = {2006}
}
@misc{Froelich1982a,
abstract = {[American Journal of Science, Vol. 282, April, 1982, P. 474-511] THE MARINE PHOSPHORUS CYCLE PN FROELICH*, ML BENDER, NA LUEDTKE** Graduate School of Oceanography, University of Rhode Island, Kingston, RI 02882, GR HEATH AND T. DeVRIES*** School of ...},
author = {Froelich, P. N. and Bender, M. L. and Luedtke, N. A.},
booktitle = {American Journal of Science},
doi = {10.3389/fmicb.2013.00105},
isbn = {0002-9599},
issn = {00029599},
number = {4},
pages = {474--511},
pmid = {23734145},
title = {{The marine phosphorus cycle}},
volume = {282},
year = {1982}
}
@article{Westrich1984,
abstract = {Laboratory study of the bacterial decomposition of Long Island Sound plankton in oxygenated seawater over a period of 2 years shows that the organic material undergoes decomposition via first-order kinetics and can be divided into two decomposable fractions, of considerably different reactivity, and a nonmetabolizable fraction. This planktonic material, after undergoing varying degrees of oxic degradation, was added in the laboratory to anoxic sediment taken from a depth of 1 m at the NWC site of Long Island Sound and the rate of bacterial sulfate reduction in the sediment measured by the {\$}{\^{}}35S{\$} radiotracer technique. The stimulated rate of sulfate reduction was in direct proportion to the amount of planktonic carbon added. This provides direct confirmation of the first-order decomposition, or G model, for marine sediments and proves that the in situ rate of sulfate reduction is organic-matter limited. Slower sulfate reduction rates resulted when oxically degraded plankton rather than fresh plankton was added, and the result confirm the presence of the same two fractions of organic matter deduced from the oxic degradation studies. Near-surface Long Island Sound sediment, which already contains abundant readily decomposable organic matter, was also subjected to anoxic decomposition by bacterial sulfate reduction. The decrease in sulfate reduction rate with time parallels decreases in the amount of organic matter, and these results also indicate the presence of two fractions of organic carbon of distinctly different reactivity. From plots of the log of reduction rate vs. time two first-order rate constants were obtained that agree well with those derived from the plankton addition experiment. Together, the two experiments confirm the use of a simple multi-first-order rate law for organic matter decomposition in marine sediments.},
author = {Westrich, Joseph T. and Berner, Robert A.},
doi = {10.4319/lo.1984.29.2.0236},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Westrich, The role of sedimentary organic matter, 1984.pdf:pdf},
isbn = {00243590},
issn = {00243590},
journal = {Limnology and Oceanography},
number = {2},
pages = {236--249},
title = {{The role of sedimentary organic matter in bacterial sulfate reduction: The G model tested}},
volume = {29},
year = {1984}
}
@article{OConnell2015,
abstract = {Vivianite [(Fe{\textless}inf{\textgreater}3{\textless}/inf{\textgreater}(PO{\textless}inf{\textgreater}4{\textless}/inf{\textgreater}){\textless}inf{\textgreater}2{\textless}/inf{\textgreater}??8H{\textless}inf{\textgreater}2{\textless}/inf{\textgreater}O)] may precipitate in anoxic lake sediments affecting the porewater orthophosphate concentration, and thereby the trophic status of lakes. We have investigated changes in lake diagenesis of Fe and P (1969-2009), with particular attention focused on vivianite formation with sediment depth (0-20cm) in an iron-silica-carbon rich lake sediment (??rns??, Denmark). Porewaters were supersaturated for vivianite by two to five orders of magnitude (upper 10cm) with porewater phosphate concentrations ranging between 0.69 and 10??moll{\textless}sup{\textgreater}-1{\textless}/sup{\textgreater}, in winter, and summer concentrations ranging between 9.8 and 40??moll{\textless}sup{\textgreater}-1{\textless}/sup{\textgreater}. Significant formation of vivianite was confirmed by X-ray diffraction while scanning electron microscopy and electron dispersive X-ray spectroscopy indicated an increase in vivianite crystal size with depth ({\~{}}20 to {\~{}}70??m across). Variations in elemental composition of vivianite crystals in relation to at.{\%} P and Fe were especially seen going from 9.5cm to 24.5cm. The total sediment Fe pool was very large {\~{}}3000??molg{\textless}sup{\textgreater}-1{\textless}/sup{\textgreater} and total P increased from 200??molg{\textless}sup{\textgreater}-1{\textless}/sup{\textgreater} to 400??molg{\textless}sup{\textgreater}-1{\textless}/sup{\textgreater} descending down the sediment profile. Differential extraction experiments of P release at pH3 estimated that vivianite amounts to between 3 and 5{\%} of the total Fe pool. The total P burial fluxes estimate that {\~{}}38??molcm{\textless}sup{\textgreater}-2{\textless}/sup{\textgreater}yr{\textless}sup{\textgreater}-1{\textless}/sup{\textgreater} or {\~{}}26{\%} of sedimentary P in the lower sediments is sequestered as vivianite. There are seasonal variations in the porewater composition with lower Fe, orthophosphate and higher sulfate concentrations during winter (5??C), than during summer (15??C). This suggests that temperature modulates the rate of organic matter degradation which in turns affects the rate of Fe(III) phase reduction, release of phosphate, and thereby the porewater Fe{\textless}sup{\textgreater}2+{\textless}/sup{\textgreater} and orthophosphate concentrations and hence vivianite formation. This work highlights the role vivianite can play for P retention in a Si-Fe-C rich lake sediment.},
author = {O'Connell, David W. and {Mark Jensen}, Marlene and Jakobsen, Rasmus and Thamdrup, Bo and {Joest Andersen}, Thorbj??rn and Kovacs, Andras and {Bruun Hansen}, Hans Christian},
doi = {10.1016/j.chemgeo.2015.05.002},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/O'connell,Vivianite formation and its role in phosphorus retention,2015.pdf:pdf},
issn = {00092541},
journal = {Chemical Geology},
keywords = {Burial flux,Eutrophication,Fe release,Fe-silicate,P release,P sequestration,Phosphate,Seasonal flux,Sulfate,Sulfide,Vivianite},
pages = {42--53},
publisher = {Elsevier B.V.},
title = {{Vivianite formation and its role in phosphorus retention in Lake Orn, Denmark}},
url = {http://dx.doi.org/10.1016/j.chemgeo.2015.05.002},
volume = {409},
year = {2015}
}
@article{Dijkstra2014,
abstract = {Phosphorus (P) is a key nutrient for marine organisms. The only long-term removal pathway for P in the marine realm is burial in sediments. Iron (Fe) bound P accounts for a significant proportion of this burial at the global scale. In sediments underlying anoxic bottom waters, burial of Fe-bound P is generally assumed to be negligible because of reductive dissolution of Fe(III) (oxyhydr)oxides and release of the associated P. However, recent work suggests that Fe-bound P is an important burial phase in euxinic (i.e. anoxic and sulfidic) basin sediments in the Baltic Sea. In this study, we investigate the role of Fe-bound P as a potential sink for P in Black Sea sediments overlain by oxic and euxinic bottom waters. Sequential P extractions performed on sediments from six multicores along two shelf-to-basin transects provide evidence for the burial of Fe-bound P at all sites, including those in the euxinic deep basin. In the latter sediments, Fe-bound P accounts for more than 20{\%} of the total sedimentary P pool. We suggest that this P is present in the form of reduced Fe-P minerals. We hypothesize that these minerals may be formed as inclusions in sulfur-disproportionating Deltaproteobacteria. Further research is required to elucidate the exact mineral form and formation mechanism of this P burial phase, as well as its role as a sink for P in sulfide-rich marine sediments.},
author = {Dijkstra, Nikki and Kraal, Peter and Kuypers, Marcel M M and Schnetger, Bernhard and Slomp, Caroline P.},
doi = {10.1371/journal.pone.0101139},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Dijkstra, are iron-phosphate minerals a sink for phosphorus in anoxic black sea seidments, 2014.PDF:PDF},
issn = {19326203},
journal = {PLoS ONE},
number = {7},
pages = {1--12},
pmid = {24988389},
title = {{Are iron-phosphate minerals a sink for phosphorus in anoxic Black Sea sediments?}},
volume = {9},
year = {2014}
}
@article{Madison2011,
author = {Madison, Andrew S and Tebo, Bradley M and {Luther III}, George W},
issn = {0039-9140},
journal = {Talanta},
number = {2},
pages = {374--381},
publisher = {Elsevier},
title = {{Simultaneous determination of soluble manganese (III), manganese (II) and total manganese in natural (pore) waters}},
volume = {84},
year = {2011}
}
@article{Delaney1998a,
abstract = {Ideas about key factors in the oceanic mass balance of dissolved, reactive phosphate have changed substantially. I present an integrated overview of these here, with an emphasis on evaluating the burial sinks for P and defining areas needing further research. The major source of reactive P to the ocean is river input. Reactive P is delivered to the oceanic sediment-water interface primarily in particulate organic matter. P scavenged by hydrothermal iron-rich oxyhydroxide particles, with uptake in proportion to deep water phosphate concentrations, represents a substantially smaller flux to the sediment-water interface. Diagenetic transformations are important influences on the form of reactive P burial in marine sediments. P burial occurs with organic carbon burial and as P associated with iron-rich oxyhydroxide particles and coatings. Formation of authigenic P-rich phases, presumably apatite, at the expense of organic P and oxide-associated P, is significant in open ocean marine sediments. The authigenic P sink may represent a substantially larger portion of the sedimentary burial than indicated by previous estimates focused on P burial in organic-rich continental margin sediments.},
author = {Delaney, M. L.},
doi = {10.1029/98GB02263},
isbn = {0886-6236},
issn = {08866236},
journal = {Global Biogeochemical Cycles},
number = {4},
pages = {563--572},
title = {{Phosphorus accumulation in marine sediments and the oceanic phosphorus cycle}},
url = {http://doi.wiley.com/10.1029/98GB02263},
volume = {12},
year = {1998}
}
@article{Delaney1998,
abstract = {Ideas about key factors in the oceanic mass balance of dissolved, reactive phosphate have changed substantially. I present an integrated overview of these here, with an emphasis on evaluating the burial sinks for P and defining areas needing further research. The major source of reactive P to the ocean is river input. Reactive P is delivered to the oceanic sediment-water interface primarily in particulate organic matter. P scavenged by hydrothermal iron-rich oxyhydroxide particles, with uptake in proportion to deep water phosphate concentrations, represents a substantially smaller flux to the sediment-water interface. Diagenetic transformations are important influences on the form of reactive P burial in marine sediments. P burial occurs with organic carbon burial and as P associated with iron-rich oxyhydroxide particles and coatings. Formation of authigenic P-rich phases, presumably apatite, at the expense of organic P and oxide-associated P, is significant in open ocean marine sediments. The authigenic P sink may represent a substantially larger portion of the sedimentary burial than indicated by previous estimates focused on P burial in organic-rich continental margin sediments.},
author = {Delaney, M. L.},
doi = {10.1029/98GB02263},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Delaney,delaney Phosphorus accumulation in marine sediments and the oceanic phosphorus cycle.,1998.pdf:pdf},
isbn = {0886-6236},
issn = {0886-6236},
journal = {Global Biogeochemical Cycles},
keywords = {http://dx.doi.org/10.1029/98GB02263, doi:10.1029/9},
number = {4},
pages = {563},
title = {{Phosphorus accumulation in marine sediments and the oceanic phosphorus cycle}},
volume = {12},
year = {1998}
}
@article{Egger2016a,
abstract = {The surface sediments in the Black Sea are un-derlain by extensive deposits of iron (Fe)-oxide-rich lake sediments that were deposited prior to the inflow of ma-rine Mediterranean Sea waters ca. 9000 years ago. The subsequent downward diffusion of marine sulfate into the methane-bearing lake sediments has led to a multitude of diagenetic reactions in the sulfate-methane transition zone (SMTZ), including anaerobic oxidation of methane (AOM) with sulfate. While the sedimentary cycles of sulfur (S), methane and Fe in the SMTZ have been extensively stud-ied, relatively little is known about the diagenetic alterations of the sediment record occurring below the SMTZ. Here we combine detailed geochemical analyses of the sediment and porewater with multicomponent diagenetic modeling to study the diagenetic alterations below the SMTZ at two sites in the western Black Sea. We focus on the dy-namics of Fe, S and phosphorus (P), and demonstrate that diagenesis has strongly overprinted the sedimentary burial records of these elements. In line with previous studies in the Black Sea, we show that sulfate-mediated AOM substan-tially enhances the downward diffusive flux of sulfide into the deep limnic deposits. During this downward sulfidization, Fe oxides, Fe carbonates and Fe phosphates (e.g., vivianite) are converted to sulfide phases, leading to an enrichment in solid-phase S and the release of phosphate to the porewater. Below the sulfidization front, high concentrations of dissolved fer-rous Fe (Fe 2+) lead to sequestration of downward-diffusing phosphate as authigenic vivianite, resulting in a transient ac-cumulation of total P directly below the sulfidization front. Our model results further demonstrate that downward-migrating sulfide becomes partly re-oxidized to sulfate due to reactions with oxidized Fe minerals, fueling a cryptic S cycle and thus stimulating slow rates of sulfate-driven AOM (∼ 1–100 pmol cm −3 d −1) in the sulfate-depleted limnic de-posits. However, this process is unlikely to explain the ob-served release of dissolved Fe 2+ below the SMTZ. Instead, we suggest that besides organoclastic Fe oxide reduction and reactivation of less reactive Fe oxides by methanogens, AOM coupled to the reduction of Fe oxides may also provide a pos-sible mechanism for the high concentrations of Fe 2+ in the porewater at depth. Our results reveal that methane plays a key role in the diagenetic alterations of Fe, S and P records in Black Sea sediments. The downward sulfidization into the limnic deposits is enhanced through sulfate-driven AOM with sulfate, and AOM with Fe oxides may provide a deep source of dissolved Fe 2+ that drives the sequestration of P in vivianite below the sulfidization front. Published by Copernicus Publications on behalf of the European Geosciences Union. 5334 M. Egger et al.: Anaerobic oxidation of methane alters sediment records},
author = {Egger, Matthias and Kraal, Peter and Jilbert, Tom and Sulu-Gambari, Fatimah and Sapart, C{\'{e}}lia J. and R{\"{o}}ckmann, Thomas and Slomp, Caroline P.},
doi = {10.5194/bg-13-5333-2016},
isbn = {1726-4170},
issn = {17264189},
journal = {Biogeosciences},
number = {18},
pages = {5333--5355},
title = {{Anaerobic oxidation of methane alters sediment records of sulfur, iron and phosphorus in the Black Sea}},
volume = {13},
year = {2016}
}
@article{Sundby1992,
abstract = {Approximately half of the sedimentation flux of particulate phosphorus in the Laurentian Trough in the Gulf of St. Lawrence is mobilized within the sediment and returned to the water column. In the oxidizing surface sediment, a major portion of the sedimentation flux of organic phosphorus is mineralized, and the released phosphate is partitioned between the pore water and surface adsorption sites. Surface-adsorbed phosphate is released to the pore water as needed to replace dissolved phosphate that escapes to the overlying water. Most of the phosphate is released deeper in the sediment column from iron oxides undergoing reduction. The nonmobilized phosphorus, which is buried with the accumulating sediment, appear to consist mostly of stable minerals such as apatite. The concentration of dissolved phosphate in sediment pore waters increases sharply across the sediment-water interface from 2 $\mu$ mol PO4 liter-1 in the bottom water to 6± 3 $\mu$ mol PO4 liter-1 in the top centimeter, remains almost constant at this value down to 5-15-cm depth, and then increases rapidly with further depth. In the region of constant concentration, phosphate is buffered by adsorption-desorption equilibria with the sediment. The production rate of phosphate, the buffering capacity of the sediment, and the thickness of the diffusive boundary layer at the sediment-water interface control the shape of the pore-water profile.},
author = {Sundby, Bj{\o}rn and Gobeil, Charles and Silverberg, Norman and Mucci, Alfonso},
doi = {10.4319/lo.1992.37.6.1129},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Sundby, The phosphorus cycle in coastal marine sediments , 1992.pdf:pdf},
isbn = {00243590},
issn = {0018-8158},
journal = {Limnology and Oceanography},
number = {September},
pages = {1129--1145},
pmid = {59},
title = {{The phosphorus cycle in coastal marine sediments}},
volume = {37},
year = {1992}
}
@article{Reed2011a,
abstract = {The present study examines oxygen and phosphorus dynamics at a seasonally hypoxic site in the Arkona basin of the Baltic Sea. A coupled benthic-pelagic reactive-transport model is used to describe the evolution of bottom-water solute concentrations, as well as pore-water and sediment profiles. Aerobic respiration dominates remineralization, with iron reduction, denitrification, and sulphate reduction playing secondary roles, while other pathways are negligible. Sediments represent a significant oxygen sink chiefly due to the aerobic degradation of organic matter, as well as nitrification and iron oxyhydroxide precipitation. Most phosphorus deposited in sediments is in organic matter, yet cycling is dominated by iron-bound phosphorus due to rapid dissimilatory iron reduction coupled with aerobic iron oxyhydroxide formation. Sustained hypoxia results in an initial decrease in sediment phosphorus content due to dissolution of phosphorus-bearing iron oxyhydroxides, resulting in a pulse of phosphate to overlying waters. Although an organic-rich layer is formed under low-oxygen conditions, enhanced remineralization of organic phosphorus relative to organic carbon tempers sedimentary phosphorus accumulation. Upon reoxygenation of bottom waters after a decade of sustained hypoxia, oxygen concentrations do not immediately achieve values observed prior to hypoxia because the organic-rich layer creates a higher benthic oxygen demand. Artificial reoxygenation of bottom waters leads to a substantial increase in the iron-bound phosphorus pool; the total phosphorus content of the sediment, however, is unaffected. A relapse into hypoxia would consequently produce a large pulse of phosphate to the overlying waters potentially exacerbating the situation.},
author = {Reed, Daniel C. and Slomp, Caroline P. and Gustafsson, Bo G.},
doi = {10.4319/lo.2011.56.3.1075},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/reed, phosphorus, model, 2011.pdf:pdf},
isbn = {0024-3590},
issn = {00243590},
journal = {Limnology and Oceanography},
number = {3},
pages = {1075--1092},
title = {{Sedimentary phosphorus dynamics and the evolution of bottom-water hypoxia: A coupled benthic-pelagic model of a coastal system}},
volume = {56},
year = {2011}
}
@article{Conley2002,
abstract = {Deep-water oxygen concentrations in the Baltic Sea are influenced by eutrophication, but also by saltwater inflows from the North Sea. In the last two decades, only two major inflows have been recorded and the lack of major inflows is believed to have resulted in a long-term stagnation of the deepest bottom water. Analyzing data from 1970 to 2000 at the basin scale, we show that the estimated volume of water with oxygen, {\textless}2 mL L(-1), was actually at a minimum at the end of the longest so-called stagnation period on record. We also show that annual changes in dissolved inorganic phosphate water pools were positively correlated to the area of bottom covered by hypoxic water, but not to changes in total phosphorus load, thus addressing the legacy of eutrophication on a basinwide scale. The variations in phosphorus pools that have occurred during the past decades do not reflect any human action to reduce inputs. The long residence time and internally controlled variation of the large P pool in the Baltic Sea has important implications for management of both N and P inputs into this eutrophicated enclosed basin.},
author = {Conley, Daniel J. and Humborg, Christoph and Rahm, Lars and Savchuk, Oleg P. and Wulff, Fredrik},
doi = {10.1021/es025763w},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Conley, hypoxia in the Baltic Sea and basin-scale chanhes in phosphorus biogeochemistry, 2002.pdf:pdf},
isbn = {0013-936X},
issn = {0013936X},
journal = {Environmental Science and Technology},
number = {24},
pages = {5315--5320},
pmid = {12521155},
title = {{Hypoxia in the baltic sea and basin-scale changes in phosphorus biogeochemistry}},
volume = {36},
year = {2002}
}
@article{Raiswell1998,
abstract = {More than two hundred aerobic continental margin, aerobic deep sea, dysaerobic, and anaerobic / euxinic sediments have been examined for their variations in different operationally defined iron fractions, each of which represents a different reactivity towards dissolved sulfide. Aerobic continental margin, deep sea, and dysaerobic sediments contain similar contents of highly reactive iron (dithionite-soluble iron plus pyrite iron), poorly reactive iron (iron soluble in HCl less that soluble in dithionite), and unreactive iron (total iron less that soluble in HCl). By contrast non-turbidite euxinic samples from the Black Sea, as well as euxinic samples from the Cariaco Basin and Framvaren are enriched in highly reactive iron. These sediments contain a small lithogenous fraction and a large biogenous, organic C-rich fraction, which decays by sulphate reduction in an iron-rich water column to form pyrite-rich sediment. Other anaerobic / euxinic samples from the Black Sea, Orca Basin, and Kau Bay contain lower concentrations of biogenous sediment and are not therefore enriched in highly reactive iron. Degrees of Pyritization (DOP) for all the aerobic, dysaerobic, and anaerobic/euxinix samples (except those low in biogenous material) are consistent with analogous ancient sediments and indicate that most pyrite formation occurs form the highly reactive iron fraction.},
archivePrefix = {arXiv},
arxivId = {arXiv:1011.1669v3},
author = {Raiswell, Robert and Canfield, Donald E.},
doi = {10.2475/ajs.298.3.219},
eprint = {arXiv:1011.1669v3},
isbn = {0002-9599},
issn = {00029599},
journal = {American Journal of Science},
number = {3},
pages = {219--245},
pmid = {15003161},
title = {{Sources of iron for pyrite formation in marine sediments}},
volume = {298},
year = {1998}
}
@article{Kraal2009,
abstract = {We investigated the phosphorus (P) and iron (Fe) fractionation in four cores with anoxic sediments, deposited during the mid-Cretaceous oceanic anoxic event 2 (∼94 Ma) and the Paleocene-Eocene thermal maximum (∼55 Ma), that were exposed to oxygen after core recovery. Surprisingly, P associated with iron oxyhydroxides (Fe-bound P) was a major P phase in these laminated sediments deposited under euxinic conditions. A significant fraction of total Fe was present as (poorly) crystalline ferric Fe. This fraction increased with increasing storage time of the investigated cores. In carbonate-poor samples, Fe-bound P accounted for up to 99{\%} of total P and its abundance correlated with pyrite contents. In samples with higher CaCO3 contents ({\textgreater}5 wt{\%} in the investigated samples), P was mostly present in authigenic Ca-P minerals, irrespective of pyrite contents. We conclude that the P fractionation in anoxic, carbonate-poor, sediments is strongly affected by pyrite oxidation that occurs when these sediments are exposed to oxygen. Pyrite oxidation produces sulfuric acid and iron oxyhydroxides. The abundance of poorly crystalline Fe oxyhydroxides provides further evidence that these were indeed formed through recent (post-recovery) oxidation rather than in situ tens of millions of years ago. The acid dissolves apatite and the released phosphate is subsequently bound in the freshly formed iron oxyhydroxides. Pyrite oxidation thus leads to a conversion of authigenic Ca-P to Fe-bound P. In more calcareous samples, CaCO3 can act as an effective buffer against acidic dissolution of Ca-P minerals. The results indicate that shielding of sediments from atmospheric oxygen is vital to preserve the in situ P fractionation and to enable a valid reconstruction of marine phosphorus cycling based on sediment records. {\textcopyright} 2009 Elsevier Ltd. All rights reserved.},
author = {Kraal, Peter and Slomp, Caroline P. and Forster, Astrid and Kuypers, Marcel M M and Sluijs, Appy},
doi = {10.1016/j.gca.2009.02.026},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
number = {11},
pages = {3277--3290},
title = {{Pyrite oxidation during sample storage determines phosphorus fractionation in carbonate-poor anoxic sediments}},
volume = {73},
year = {2009}
}
@article{Bouwman2013,
abstract = {In river basins, soils, groundwater, riparian zones and floodplains, streams, rivers, lakes and reservoirs act as successive filters in which the hydrology, ecology and biogeochemical processing are strongly coupled and together act to retain a significant fraction of the nutrients transported. This paper compares existing river ecology concepts with current approaches to describe river biogeochemistry, and assesses the value of these concepts and approaches for understanding the impacts of interacting global change disturbances on river biogeochemistry. Through merging perspectives, concepts, and modeling techniques, we propose integrated model approaches that encompass both aquatic and terrestrial components in heterogeneous landscapes. In this model framework, existing ecological and biogeochemical concepts are extended with a balanced approach for assessing nutrient and sediment delivery, on the one hand, and nutrient in-stream retention on the other hand.},
author = {Bouwman, A. F. and Bierkens, M. F P and Griffioen, J. and Hefting, M. M. and Middelburg, J. J. and Middelkoop, H. and Slomp, C. P.},
doi = {10.5194/bg-10-1-2013},
isbn = {1726-4170},
issn = {17264170},
journal = {Biogeosciences},
number = {1},
pages = {1--23},
pmid = {85950193},
title = {{Nutrient dynamics, transfer and retention along the aquatic continuum from land to ocean: Towards integration of ecological and biogeochemical models}},
volume = {10},
year = {2013}
}
@misc{Canfield1992,
abstract = {Sediment from the FOAM (Friends of Anoxic Mud) site in Long Island Sound, Connecticut, was partitioned into several different size fractions (and magnetite), and the concentration and isotopic composition of sulfur in each fraction was determined. Size fractions were chosen to represent different associations of pyrite with iron. For example, pyrite in the 4 to 21 mum size fraction was mostly framboidal and the earliest formed; by contrast pyrite in the 21 to 63 mum size fraction was found to form later and only on and within the layers of sheet silicate minerals. Sulfur isotopes were found to reflect the various stages of pyrite formation, with later formed pyrites up to 40 permil heavier in S-34 than the earliest formed pyrites. Sulfur concentration data show that iron is reacted from sheet silicates (the largest pool of unpyritized iron at FOAM) with a half-life of about 100,000 yrs. Sheet silicates react with sulfide about 10(8) times more slowly than the most reactive iron oxyhydroxides in sediments. Such dramatic differences in reactivity explain why sulfide builds up in pore solution after iron oxides are consumed in pyrite formation. Lastly, these data demonstrate that calculated values of sediment DOP (degree of pyritization) cannot be used to demonstrate uniquely iron or sulfur limitation in pyrite formation. Rather, what limits pyrite formation will depend on the relative rates of sulfate reduction compared to rates of sulfide reaction with iron minerals; DOP does not yield information on these factors.},
archivePrefix = {arXiv},
arxivId = {American Journal of Science},
author = {Canfield, D. E. and Raiswell, R. and Bottrell, S.},
booktitle = {American Journal of Science},
doi = {10.2475/ajs.292.9.659},
eprint = {American Journal of Science},
isbn = {0002-9599},
issn = {00029599},
number = {9},
pages = {659--683},
pmid = {286},
title = {{The reactivity of sedimentary iron minerals toward sulfide}},
volume = {292},
year = {1992}
}
@article{Burdige1993,
abstract = {Manganese and iron reduction in marine sediments are known to play important roles in the biogeochemical cycles of many elements, including carbon, sulfur, phosphorus and several trace elements. These reduction reactions affect these cycles on a variety of time scales, ranging from those as short as seasonal time scales (e.g., nutrient cycling in coastal ecosystems), to those as long as thousands to tens of thousands of years (e.g., glacial-interglacial transformations in deep sea sediments). In this review article I will briefly summarize the results of laboratory studies on the types of manganese and iron reduction that are known to occur in marine sediments, and then discuss the occurrence of these processes in different sedimentary environments. Particular efforts will be given to examining the rates and mechanisms of sedimentary manganese and iron reduction in relationship to other biogeochemical processes in sediments.},
author = {Burdige},
doi = {10.1016/0012-8252(93)90040-E},
isbn = {0012-8252},
issn = {00128252},
journal = {Earth Science Reviews},
number = {3},
pages = {249--284},
pmid = {165},
title = {{The biogeochemistry of manganese and iron reduction in marine sediments.}},
url = {dx.doi.org/10.1016/0012-8252(93)90040-E},
volume = {35},
year = {1993}
}
@article{Redfield1958,
abstract = { IT IS a recognized principle of ecology that the interactions of organ isms and environment are reciprocal. The environment not only determines the conditions under which life exists, but the organisms influence the conditions prevailing in their environment. The examples$\backslash$r$\backslash$n on which this principle rests are usually difficult to describe in quantita$\backslash$r$\backslash$n tive terms and are frequently local in their application. In the ocean$\backslash$r$\backslash$n the principal interactions between organisms and environment are$\backslash$r$\backslash$n chemical. Because of its unity, its fluid nature, and the intensity of the$\backslash$r$\backslash$n mixing to which the water is subject their relations can be examined$\backslash$r$\backslash$n statistically and expressed in quantitative terms.$\backslash$r$\backslash$n The purpose of this essay is to discuss the relations between the$\backslash$r$\backslash$n statistical proportions in which certain elements enter into the bio$\backslash$r$\backslash$n chemical cycle in the sea, and their relative availability in the water.$\backslash$r$\backslash$n These relations suggest not only that the nitrate present in sea water$\backslash$r$\backslash$n and the oxygen of the atmosphere have been produced in large part by$\backslash$r$\backslash$n},
archivePrefix = {arXiv},
arxivId = {arXiv:1011.1669v3},
author = {Redfield, Alfred C.},
doi = {10.2307/27828530},
eprint = {arXiv:1011.1669v3},
isbn = {00030996},
issn = {00030996},
journal = {American Scientist},
number = {230},
pages = {205--221},
pmid = {1},
title = {{The Biological Control of Chemical Factors in the Environment}},
url = {http://www.jstor.org/stable/27827150},
volume = {46},
year = {1958}
}
@article{Marttila2016,
abstract = {Quantification of suspended sediment yield from rivers is essential to determining how land cover and land use affect water quality in fluvial ecosystems and erosion rates in catchment basins. In this study we used long-term (1967-2011) river-runoff and sediment concentration data to seek new insights into suspended sediment transport and its governing factors. We found that long-term suspended sediment concentrations and yield of very fine sediment ({\textless} 0.4-1.2 mu m) are dependent on: (i) temporal changes in biogeochemical processes in catchment soils and fluvial systems, and (ii) temporal variations in metal humate colloid concentrations, especially in peat-covered catchments. The results also showed that the proportion of very fine sediment varies seasonally and can significantly affect transport rates in boreal rivers. Thus national monitoring activities should include parameters describing the quality of suspended sediment (e.g. particle size range and loss on-ignition) in order to provide information relevant to land management and ecological assessments in boreal rivers.},
author = {Marttila, H and Nieminen, M L and Arje, J and Meissner, K and Tuukkanen, T and Saukkoriipi, J and Klove, B},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Marttila, dynamics of temporal changes in suspended sediment, 2016.pdf:pdf},
isbn = {1239-6095},
journal = {Boreal Environment Research},
number = {5-6},
pages = {541--555},
title = {{Dynamics and temporal changes in suspended sediment transport in northern Finland: transport of very fine particulate matter}},
volume = {21},
year = {2016}
}
@article{Rooze2016,
author = {Rooze, Jurjen and Egger, Matthias and Tsandev, Iana and Slomp, Caroline P.},
doi = {10.1002/lno.10275},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Rooze2016{\_}L{\&}O.pdf:pdf},
issn = {19395590},
journal = {Limnology and Oceanography},
number = {1},
title = {{Iron-dependent anaerobic oxidation of methane in coastal surface sediments: Potential controls and impact}},
year = {2016}
}
@incollection{Slomp2011,
abstract = {Abstract Phosphorus (P) is a key biogeochemical element supporting$\backslash$nphytoplankton growth and fish production in estuaries and on continental$\backslash$nshelves. This chapter reviews the role of rivers as the ultimate$\backslash$nsource of P in the marine realm, of burial in sediments as the major$\backslash$nsink, and of recycling of P in coastal systems. The impact of human$\backslash$nactivities and climate change in modulating P dynamics in coastal$\backslash$nenvironments and its global scale significance are also discussed.$\backslash$n},
author = {Slomp, C.P.},
booktitle = {Treatise on Estuarine and Coastal Science},
doi = {10.1016/B978-0-12-374711-2.00506-4},
isbn = {9780123747112},
issn = {978-0-08-087885-0},
pages = {201--229},
title = {{Phosphorus cycling in the estuarine and coastal zones}},
year = {2011}
}
@article{Martin1979,
abstract = {An estimate of average river particulate matter (RPM) composition was b{\`{a}}sed on analyses of more than 40 elements in the Amazon, Congo, Ganges, Magdalena, Mekong, Parana and Orinoco rivers, to which were added literature data for 13 other major world rivers, covering the whole spectrum of morphoclimatic features. Geographic variations of major elements in RPM are mostly linked to weathering types and to the balance between weathering rate and river transport. As a result of chemical erosion, Al, Fe and Ti are enriched in RPM with respect to the average parent rock, while Na, Ca, Mg and Sr are strongly depleted. These figures are directly related to the relative importance of dissolved and particulate transport in rivers; this has been computed for each of 40 elements. In order to study weathering on a global scale, the total observed elemental fluxes (dissolved + particulate) have been computed and compared to theoretical ones. The latter were derived from the elemental content in the average parent rock and the total quantity of weathered material, computed from the Al ratio in RPM and in parent rock. Observed and theoretical fluxes are balanced for the less mobilized elements (rare earths, Co, Cr, Cs, Fe, Mn, Rb, Si, Th, Ti, U and V) for which no enrichment relative to Al is noted in RPM, and for B, Ba, Ca, K, Mg, Na, Sr which are relatively depleted in RPM due to their high dissolved transport. Additional fluxes have been found for Br, Sb, Pb, Cu, Mo, Zn and are possible also for Ni and P. This is reflected by marked enrichments in RPM relative to Al for the poorly or moderately dissolved transports (Pb, Cu, Zn). Several hypotheses involving either the natural origin (volcanic dust, marine aerosols, geochemical fractionation) or the artificial origin (worldwide pollution) are discussed to explain these discrepancies, assuming river transport and weathering either to be in a steady state on a global scale or not. However, none of them can fully account for these additional fluxes. It is most likely that these excesses have multiple origins, anthropogenic or natural or both. The comparison between RPM and deep-sea clay compositions emphasizes the prime influence of river input on oceanic sedimentation of Si, Al, Fe, Ti, lanthanides, Sc, Rb, V, etc. A few elements such as Zn, Sb, occur in excess in RPM as compared to deep-sea clays; in order to balance this excess, a remobilization of these elements out of the sediment can be considered. Finally, the enrichment of Co, Cu, Mn and Ni in deep-sea clays compared to RPM is discussed and attributed to several sources and processes. {\textcopyright} 1979.},
author = {Martin, Jean Marie and Meybeck, Michel},
doi = {10.1016/0304-4203(79)90039-2},
isbn = {0304-4203},
issn = {03044203},
journal = {Marine Chemistry},
number = {3},
pages = {173--206},
pmid = {2391},
title = {{Elemental mass-balance of material carried by major world rivers}},
volume = {7},
year = {1979}
}
@article{Gogina2016,
abstract = {This study provides an inventory of the recent benthic macrofaunal communities in the entire Baltic Sea. The analyses of soft-bottom benthic inver-tebrate community data based on over 7000 locations in the Baltic Sea suggested the existence of 10 major communities based on species abundances and 17 communities based on species biomasses, respectively. The low-saline northern Baltic, characterized by silty sediments, is dominated by Monoporeia affinis, Marenzelleria spp., and Macoma balthica. Hydrobiidae, Pygospio elegans, and Cerastoderma glaucum dominate the community in sandy habitats off the Estonian west coast and in the southeastern and southern Baltic Sea. Deep parts of the Gulf of Finland and central Baltic Sea often experience hypoxia, and when oxygen levels in these regions recover, Bylgides sarsi was the first species to colonize. The southwestern Baltic Sea, with high salinity, has higher macrofaunal diversity compared with the northern parts. To spatially interpolate the distribution of the major communities, we used the Random Forest method. Substrate data, bathymetric maps, and modelled hydrographical fields were used as predictors. Model predictions were in good agreement with observations, quantified by Cohen's k of 0.90 for the abundance and 0.89 in the wet weight-based model. Misclassifications were mainly associated with uncommon classes in regions with high spatial variability. Our analysis provides a detailed baseline map of the distribution of benthic communities in the Baltic Sea to be used both in science and management.},
author = {Gogina, Mayya and Nyg{\aa}rd, Henrik and Blomqvist, Mats and Daunys, Darius and Josefson, Alf B. and Kotta, Jonne and Maximov, Alexey and Warzocha, Jan and Yermakov, Vadim and Gr{\"{a}}we, Ulf and Zettler, Michael L.},
doi = {10.1093/icesjms/fsv265},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Gogina, Baltic sea inventory benthic fauna, 2016.pdf:pdf},
issn = {10959289},
journal = {ICES Journal of Marine Science},
keywords = {Baltic Sea,Random Forest,community analysis,large scale,macrozoobenthos,spatial distribution},
number = {4},
pages = {1196--1213},
title = {{The Baltic Sea scale inventory of benthic faunal communities}},
volume = {73},
year = {2016}
}
@article{Krom1980,
abstract = {The adsorption of dissolved phosphate in anoxic marine sediments has been investigated in samples of mud from two locations in Long Island Sound kept under strictly anoxic conditions. Kinetic experiments showed that desorption is more rapid than adsorption, but that both reach equilibrium within 24 h. The process of adsorption of phosphate can be described by a simple linear isotherm: the dimensionless in situ adsorption coefficient (K) determined from four separate runs on mud from the FOAM site was 1.7± 0.2; for sediment from the NWC site it was 1.9. Diffusion measurements provide independent experimental confirmation of this value of K. These values of K are much lower than those in oxic sediments because the iron oxyhydroxides which are important in the adsorption of phosphate in oxic sediments are converted to iron sulfides in anoxic muds.},
author = {Krom, Michael D. and Berner, Robert A.},
doi = {10.4319/lo.1980.25.5.0797},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Krom, Adsorption of phosphate in anoxic marine sediments, 1980.pdf:pdf},
isbn = {00243590},
issn = {00243590},
journal = {Limnology and Oceanography},
number = {5},
pages = {797--806},
pmid = {409},
title = {{Adsorption of Phosphate in Anoxic Marine Sediments}},
url = {http://www.jstor.org/stable/2836052},
volume = {25},
year = {1980}
}
@article{Boetius2000a,
abstract = {A large fraction of globally produced methane is converted to CO2 by anaerobic oxidation in marine sediments. Strong geochemical evidence for net methane consumption in anoxic sediments is based on methane profiles, radiotracer experiments and stable carbon isotope data. But the elusive microorganisms mediating this reaction have not yet been isolated, and the pathway of anaerobic oxidation of methane is insufficiently understood. Recent data suggest that certain archaea reverse the process of methanogenesis by interaction with sulphate-reducing bacteria. Here we provide microscopic evidence for a structured consortium of archaea and sulphate-reducing bacteria, which we identified by fluorescence in situ hybridization using specific 16S rRNA-targeted oligonucleotide probes. In this example of a structured archaeal-bacterial symbiosis, the archaea grow in dense aggregates of about 100 cells and are surrounded by sulphate-reducing bacteria. These aggregates were abundant in gas-hydrate-rich sediments with extremely high rates of methane-based sulphate reduction, and apparently mediate anaerobic oxidation of methane.},
author = {Boetius, Antje and Ravenschlag, Katrin and Schubert, Carsten J and Rickert, Dirk and Widdel, Friedrich and Gieseke, Armin and Amann, Rudolf and J{\o}rgensen, Bo Barker and Witte, Ursula and Pfannkuche, Olaf},
doi = {10.1038/35036572},
isbn = {0028-0836 (Print)$\backslash$r0028-0836 (Linking)},
issn = {00280836},
journal = {Nature},
number = {6804},
pages = {623--626},
pmid = {11034209},
title = {{A marine microbial consortium apparently mediating anaerobic oxidation of methane}},
url = {http://www.nature.com/doifinder/10.1038/35036572},
volume = {407},
year = {2000}
}
@article{Bartlett1954,
author = {Bartlett, J K and Skoog, D A},
doi = {10.1021/ac60090a014},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Methods/Extractions/Sulfur/Elementair S meten/Bartlett{\_}1954{\_}AnalChem{\_}Colorimetric determination elemental S.pdf:pdf},
isbn = {0003-2700},
issn = {0003-2700},
journal = {Analytical Chemistry},
number = {6},
pages = {1008--1011},
title = {{Colorimetric determination of elemental sulfur in hydrocarbons}},
volume = {26},
year = {1954}
}
@article{Rozan2002,
abstract = {We conducted a study to determine the seasonal relationship between iron, sulfur, and phosphorus in the upper sediments and pore waters of a shallow intercoastal bay. From April 1999 to September 2000, sediment cores were collected from Rehoboth Bay, Delaware. Analyses of the sediments in the upper 4 cm revealed that redox conditions controlled Fe-S-P concentrations in the sediments, pore waters, and overlying water. Monthly sampling showed a marked decrease in the reactive solid phase P pool (ascorbate leachable fraction, ASC-P) and sharp increases in soluble P (measured as PO) in pore waters and overlying waters, as the conditions became more reducing through-3Ϫ 4},
author = {Rozan, Tim F and Taillefert, Martial and Trouwborst, Robert E and Glazer, Brian T and Ma, Shufen and Herszage, Julian and Valdes, Lexia M and Price, Kent S and {Luther III}, George W},
doi = {10.4319/lo.2002.47.5.1346},
isbn = {00243590},
issn = {0024-3590},
journal = {Limnol. Oceanogr.},
number = {5},
pages = {1346--1354},
title = {{Iron sulfur phosphorus cycling in the sediments of a shallow coastal bay: Implications for sediment nutrient release and benthic macroalgal blooms}},
volume = {47},
year = {2002}
}
@article{Leipe2011,
abstract = {In this study, particulate organic carbon (POC) contents and their distribution pattern in surficial sediments of the Baltic Sea are presented for 1,471 sampling stations. POC contents range from approx. 0.1{\%} in shallow sandy areas up to 16{\%} in deep muddy basins (e.g. Gotland Basin). Some novel relationships were identified between sediment mass physical properties (dry bulk density (DBD), grain size) and POC levels. Notably, the highest POC concentrations (about 10–17 mg cm–3) occur in sandy mud to mud (60–100{\%} mud content) with intermediate POC contents of about 3–7{\%} and DBDs of 0.1–0.4 g cm–3. Areas with this range in values seem to represent the optimum conditions for POC accumulation in the Baltic Sea. The maximum POC contents (8–16{\%}) are found in fluid mud of the central Baltic Sea characterized by extremely low DBDs ({\textless}0.1 g cm–3) and moderate POC concentrations (4–7 mg cm–3). Furthermore, sediment mass accumulation rates (MAR), based on 210Pb and 137Cs measurements and available for 303 sites of the Baltic Sea, were used for assessing the spatial distribution of POC burial rates. Overall, these vary between 14 and 35 g m–2 year–1 in the mud depositional areas and, in total, at least 3.5 (±2.9) Mt POC are buried annually. Distribution patterns of POC contents and burial rates are not identical for the central Baltic Sea because of the low MAR in this area. The presented data characterize Baltic Sea sediments as an important sink for organic carbon. Regional differences in organic carbon deposition can be explained by the origin and transport pathways of POC, as well as the environmental conditions prevailing at the seafloor (morphology, currents, redox conditions). These findings can serve to improve budget calculations and modelling of the carbon cycle in this large brackish-water marginal sea.},
author = {Leipe, Thomas and Tauber, Franz and Vallius, Henry and Virtasalo, Joonas and U{\'{s}}cinowicz, Szymon and Kowalski, Nicole and Hille, Sven and Lindgren, Susanna and Myllyvirta, Tero},
doi = {10.1007/s00367-010-0223-x},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Leipe,  Particulate organic carbon (POC) in surface sediments of the Baltic Sea, 2011.pdf:pdf},
isbn = {0276-0460},
issn = {02760460},
journal = {Geo-Marine Letters},
number = {3},
pages = {175--188},
title = {{Particulate organic carbon (POC) in surface sediments of the Baltic Sea}},
volume = {31},
year = {2011}
}
@article{Mackin1984,
abstract = {One important reaction which affects dissolved NH,+ distributions in marine sediments is reversible adsorption on sediment solids. We investigate both the temperature dependency and spatial variability of the NH,+ linear adsorption coefficient, K, in marine scdimcnts. For a wide range of environments, because of approximately offsetting variations in sediment porosity and properties such as clay mineral and organic matter content, K is nearly constant (1.3 + 0.1) in terrigenous, surface, marine sediments. The value of K also does not vary significantly as a function of temperature. In biogenic and very high porosity ({\~{}}0.95) sediments K may be somewhat lower than for other sedimentarv environments. Sediments containing seagrass detritus such as Thalassia may be expected to exhibit relatively high K values.},
author = {Mackin, James E. and Aller, Robert C.},
doi = {10.4319/lo.1984.29.2.0250},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/mackin aller, nh4 oxidation.pdf:pdf},
isbn = {0024-3590},
issn = {00243590},
journal = {Limnology and Oceanography},
number = {2},
pages = {250--257},
title = {{Ammonium adsorption in marine sediments}},
volume = {29},
year = {1984}
}
@article{Hellemann2017,
author = {Hellemann, Dana and Tallberg, Petra and Bartl, Ines and Voss, Maren and Hietanen, Susanna},
doi = {10.3354/meps12359},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Hellemann2017{\_}MarEcolProgSer (3).pdf:pdf},
issn = {01718630},
journal = {Marine Ecology Progress Series},
keywords = {Coastal filter,Isotope pairing technique,Nitrogen,Northern Baltic Sea,Particulate organic nitrogen,Quark Strait,Sand sediment},
number = {Nixon 1995},
pages = {63--80},
title = {{Denitrification in an oligotrophic estuary: A delayed sink for riverine nitrate}},
volume = {583},
year = {2017}
}
@book{APHA2005,
abstract = {With new content and over 40{\%} of the sections updated Standard Methods for the Examination of Water and Wastewater™ 22nd edition provides methods for measuring the biological, chemical, and physical attributes of waters, and offers guidance for choosing among available methods for specific elements and compounds. Analysts, researchers, and regulators have relied on this peer-reviewed publication since 1905, and it remains a trusted source of accurate, proven methodology for analyzing natural waters, water supplies, and wastewaters. Published by the American Public Health Association, the American Water Works Association, and the Water Environment Federation.},
author = {APHA},
booktitle = {American Water Works Association/American Public Works Association/Water Environment Federation},
doi = {10.2105/AJPH.51.6.940-a},
isbn = {9780875530475},
pages = {1469},
title = {{Standard methods for the examination of water and wastewater}},
year = {2005}
}
@article{Bjorkvald2008,
abstract = {Stream water from a stream network of 15 small boreal catchments (0.03-67 km2) in northern Sweden was analyzed for unfiltered (total) and filtered ({\textless}0.4 ??m) concentrations of iron (Fetot and Fe{\textless}0.4) and manganese (Mntot and Mn{\textless}0.4). The purpose was to investigate the temporal and spatial dynamics of Fe, Mn and dissolved organic carbon (DOC) as influenced by snow melt driven spring floods and landscape properties, in particular the proportion of wetland area. During spring flood, concentrations of Fetot, Fe{\textless}0.4, Mntot, Mn{\textless}0.4 and DOC increased in streams with forested catchments ({\textless}2{\%} wetland area). In catchments with high coverage of wetlands ({\textgreater}30{\%} wetland area) the opposite behavior was observed. The hydrogeochemistry of Fe was highly dependent on wetlands as shown by the strong positive correlation of the Fetot/Altot ratio with wetland coverage (r2 = 0.89, p {\textless} 0.001). Furthermore, PCA analysis showed that at base flow Fetot and Fe{\textless}0.4 were positively associated with wetlands and DOC, whereas they were not associated during peak flow at spring flood. The temporal variation of Fe was likely related to varying hydrological pathways. At peak discharge Fetot was associated with variables like silt coverage, which highlights the importance of particulates during high discharge events. For Mn there was no significant correlation with wetlands, instead, PCA analysis showed that during spring flood Mn was apparently more dependent on the supply of minerogenic particulates from silt deposits on the stream banks of some of the streams. The influence of minerogenic particulates on the concentration of, in particular, Mn was greatest in the larger, lower gradient streams, characterized by silt deposits in the near-stream zone. In the small forested streams underlain by till, DOC was of greater importance for the observed concentrations, as indicated by the positive correlation of both Fetot and Fe{\textless}0.4 with DOC (r2 = 0.77 and r2 = 0.76, p {\textless} 0.001) at the smallest headwater forest site. In conclusion, wetland area and DOC were important for Fe concentrations in this boreal stream network, whereas silt deposits strongly influenced Mn concentrations. This study highlights the importance of studying stream water chemistry from a landscape perspective in order to address future environmental issues concerning mobility of Fe, Mn and associated trace metals. ?? 2008 Elsevier Ltd. All rights reserved.},
author = {Bj{\"{o}}rkvald, Louise and Buffam, Ishi and Laudon, Hjalmar and M{\"{o}}rth, Carl Magnus},
doi = {10.1016/j.gca.2008.03.024},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Bjorkvald, Hydrogeochemistry of Fe and Mn in small boreal streams, 2008.pdf:pdf},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
number = {12},
pages = {2789--2804},
title = {{Hydrogeochemistry of Fe and Mn in small boreal streams: The role of seasonality, landscape type and scale}},
volume = {72},
year = {2008}
}
@article{Schwertmann2004,
abstract = {2-line ferrihydrite stored in water at ambient temperatures from 4 to 25{\&}{\#}176;C and at ten different pH values between 2.5 and 12 for up to 10{\&}{\#}150;12 y transformed to both goethite and hematite at all temperatures and pH values except at pH 12 where only goethite was formed. The rate and degree of transformation (20{\&}{\#}150;100{\&}{\#}037;) increased with increasing pH and temperature. The hematite/ (hematite+goethite) ratio varied between 0 and {\~{}}0.8, increased with increasing temperature and showed a strong maximum at pH 7{\&}{\#}150;8 which increased from 0.1{\&}{\#}150;0.2 at 4{\&}{\#}176;C to 0.7{\&}{\#}150;0.8 at 25{\&}{\#}176;C. The maximum coincides with the zero point of charge of ferrihydrite where its solubility and, thus, its via-solution transformation rate to goethite are minimal. We assume, therefore, that in this pH-range the (slower) via-solution transformation to hematite can more efficiently compete with that to goethite.},
author = {Schwertmann, U. and Stanjek, H. and Becher, H.-H.},
doi = {10.1180/0009855043940145},
isbn = {0009-8558},
issn = {00098558},
journal = {Clay Minerals},
number = {4},
pages = {433--438},
title = {{Long-term{\textless}I{\textgreater} in vitro{\textless}/I{\textgreater} transformation of 2-line ferrihydrite to goethite/hematite at 4, 10, 15 and 25°C}},
url = {http://www.ingentaselect.com/rpsv/cgi-bin/cgi?ini=xref{\&}body=linker{\&}reqdoi=10.1180/0009855043940145},
volume = {39},
year = {2004}
}
@article{Strickland1972,
abstract = {analysis; tpm; pim; pom; chlorophyll-a; strickland; seawater},
author = {Strickland, J. D. H. and Parsons, T. R.},
doi = {10.1002/iroh.19700550118},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Strickland-Parsons{\_}1972.pdf:pdf},
isbn = {9780660115962},
issn = {00209309},
journal = {A practical handbook of seawater analysis},
keywords = {analysis,chlorophyll-a,pim,pom,seawater,strickland,tpm},
pages = {185},
pmid = {19457},
title = {{A Practical Handbook of Seawater Analysis}},
volume = {167},
year = {1972}
}
@article{Scavia2002,
abstract = {Increases in concentrations of greenhouse gases projected for the 21st century are expected to lead to increased mean global air and ocean temperatures. The National Assessment of Potential Consequences of Climate Variability and Change (NAST 2001) was based on a series of regional and sector assessments. This paper is a summary of the coastal and marine resources sector review of potential impacts on shorelines, estuaries, coastal wetlands, coral reefs, and ocean margin ecosystems. The assessment considered the impacts of several key drivers of climate change: sea level change; alterations in precipitation patterns and subsequent delivery of freshwater, nutrients, and sediment; increased ocean temperature; alterations in circulation patterns; changes in frequency and intensity of coastal storms; and increased levels of atmospheric CO 2 . Increasing rates of sea-level rise and intensity and frequency of coastal storms and hurricanes over the next decades will increase threats to shorelines, wetlands, and coastal development. Estuarine productivity will change in response to alteration in the timing and amount of freshwater, nutrients, and sediment delivery. Higher water temperatures and changes in freshwater delivery will alter estuarine stratification, residence time, and eutrophication. Increased ocean temperatures are expected to increase coral bleaching and higher CO 2 levels may reduce coral calcification, making it more difficult for corals to recover from other disturbances, and inhibiting poleward shifts. Ocean warming is expected to cause poleward shifts in the ranges of many other organisms, including commercial species, and these shifts may have secondary effects on their predators and prey. Although these potential impacts of climate change and variability will vary from system to system, it is important to recognize that they will be superimposed},
author = {Scavia, Donald and Field, John C and Boesch, Donald F and Buddemeier, Robert W and Burkett, Virginia and Cayan, Daniel R and Fogarty, Michael and Harwell, Mark A and Howarth, Robert W and Mason, Curt and Reed, Denise J and Royer, Thomas C and Sallenger, Asbury H and Titus, James G},
doi = {10.1007/BF02691304},
isbn = {0160-8347},
issn = {1559-2723},
journal = {Estuarine Research Federation Estuaries},
number = {2},
pages = {149--164},
title = {{Climate change impacts on U.S. coastal and marine ecosystems}},
volume = {149},
year = {2002}
}
@article{Dijkstra2018,
abstract = {Phosphorus (P) concentrations in sediments are frequently used to reconstruct past environmental conditions in freshwater and marine systems, with high values thought to be indicative of a high biological productivity. Recent studies suggest that the post-depositional formation of vivianite, an iron(II)-phosphate mineral, might significantly alter trends in P with sediment depth. To assess its importance, we investigate a sediment record from the Bornholm Basin that was retrieved during the Integrated Ocean Drilling Program (IODP) Baltic Sea Paleoenvironment Expedition 347 in 2013, consisting of lake sediments overlain by brackish–marine deposits. Combining bulk sediment geochemistry with microanalysis using scanning electron microscope energy dispersive spectroscopy (SEM-EDS) and synchrotron-based X-ray absorption spectroscopy (XAS), we demonstrate that vivianite-type minerals rich in manganese and magnesium are present in the lake deposits just below the transition to the brackish–marine sediments (at 11.5 to 12 m sediment depth). In this depth interval, phosphate that diffuses down from the organic-rich, brackish–marine sediments meets porewaters rich in dissolved iron in the lake sediments, resulting in the precipitation of iron(II) phosphate. Results from a reactive transport model suggest that the peak in iron(II) phosphate originally occurred at the lake–marine transition (9 to 10 m) and moved downwards due to changes in the depth of a sulfidization front. However, its current position relative to the lake–marine transition is stable as the vivianite-type minerals and active sulfidization fronts have been spatially separated over time. Experiments in which vivianite was subjected to sulfidic conditions demonstrate that incorporation of manganese or magnesium in vivianite does not affect its susceptibility to sulfide-induced dissolution. Our work highlights that post-depositional formation of iron(II) phosphates such as vivianite has the potential to strongly alter sedimentary P records particularly in systems that are subject to environmental perturbation, such as a change in primary productivity, which can be associated with a lake–marine transition.},
author = {Dijkstra, Nikki and Hagens, Mathilde and Egger, Matthias and Slomp, Caroline P.},
doi = {10.5194/bg-15-861-2018},
issn = {17264189},
journal = {Biogeosciences},
number = {3},
pages = {861--883},
title = {{Post-depositional formation of vivianite-type minerals alters sediment phosphorus records}},
volume = {15},
year = {2018}
}
@article{Roden1997,
abstract = {Mechanisms of phosphate (PO43- mobilization and retention were examined in iron-rich anaerobic freshwater wetland, lake, and coastal marine sediments. Direct microbial Fe(III) oxide reduction solubilized only 3-25{\%} of initial solid-phase PO43- during sulfate-free sediment incubation experiments. Experiments with reduced, non-sulfidic solid-phase Fe(II)-rich sediment demonstrated PO43- sorption by the solid-phase, and chemical equilibrium calculations indicated that conditions were favorable for precipitation of Fe(II)-PO4 minerals [e.g. Fe-3(PO4)(2)] in such sediments. These results suggested that much of the PO43- released from Fe(III) oxides during microbial Fe(III) reduction was captured by solid-phase reduced iron compounds (Fe(II) hydroxide-PO4 complexes and/or Fe(II)-PO4 minerals). Enhanced liberation of PO43- to sediment porewaters (33-100{\%} of initial solid-phase PO43- occurred during anaerobic incubation in the presence of abundant sulfate and was directly correlated with sulfate reduction and iron-sulfide mineral formation. Incubation of PO43--amended sediment with different amounts of sulfate demonstrated a linear correlation between PO43- release and sulfate reduction. Release of Po-4(3-) to sediment porewaters during decomposition of fresh organic matter (freeze-dried cyanobacteria) was more extensive in sulfate-amended (67{\%} of added organic P) than in sulfate-free sediment (17{\%} of added organic P), and the ratio of dissolved PO43- released to organic carbon oxidized was seven-fold higher in sulfate-amended sediment despite a common level of overall organic C and P mineralization in the two treatments. Our results demonstrate that iron-rich anaerobic sediments can immobilize substantial amounts of PO43- under Fe(III) oxide-reducing conditions, but that extensive PO43- release will take place if sediment Fe compounds are converted to iron-sulfides via bacterial sulfate reduction.},
author = {Roden, Eric E. and Edmonds, Jennifer W.},
isbn = {0003-9136},
issn = {0003-9136},
journal = {Archiv Fur Hydrobiologie},
number = {3},
pages = {347--378},
title = {{Phosphate mobilization in iron-rich anaerobic sediments: Microbial Fe(III) oxide reduction versus iron-sulfide formation}},
volume = {139},
year = {1997}
}
@article{Hsu2014,
abstract = {Authigenesis of iron-rich phosphate nodules occurs in iron-rich cold-seep sediments (MD052911 core) at Yung-An Ridge offshore southwestern Taiwan. Raman, FTIR, and quantitative X-ray energy-dispersive spectroscopic analyses indicate that the phosphate mineral is vivianite (or bari{\'{c}}ite) and shows Fe/Mg molar ratios spanning from ca. 0.6 to 4.0 and a general down core trend of increasing Fe/Mg ratios. The formation of vivianite is limited to a depth interval of 13–17mbsf (meters below seafloor) and is most prominent at ∼16mbsf in association with high dissolved iron concentrations and depleted dissolved sulfide below a peak sulfidization zone (enriched in mackinawite and greigite). Alternate growths of vivianite and iron monosulfides and compositional zoning with Mg enriched towards the peripheries of individual nodules occur in the transition from the zone of vivianite mineralization to the sulfidization zone. The crystallization of vivianite below the sulfidization front could have been favored by scavenging of downward diffusive dissolved sulfide from pore waters in the sulfidization zone. Alternate growths and overlapping of the zones of iron monosulfides and vivianite can be attributed to fluctuations of the sulfidization front and methane flux. The discovery of vivianite in the Yung-An Ridge sediments implies that authigenic vivianite can be an important sink for phosphorus burial in cold-seep sediments that have high reactive-iron contents and high sedimentation rates.},
author = {Hsu, Ta-Wei and Jiang, Wei-Teh and Wang, Yunshuen},
doi = {10.1016/j.jseaes.2014.03.027},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Hsu,Authigenesis of vivianite as influenced by methane-induced sulfidization, 2014.pdf:pdf},
isbn = {1367-9120},
issn = {13679120},
journal = {Journal of Asian Earth Sciences},
keywords = {Anaerobic methane oxidation,Gas hydrate,Iron phosphate,Microanalysis,Sulfidization front},
number = {August 2014},
pages = {88--97},
title = {{Authigenesis of vivianite as influenced by methane-induced sulfidization in cold-seep sediments off southwestern Taiwan}},
volume = {89},
year = {2014}
}
@article{Petzold1983,
abstract = {This paper describes a scheme for automatically determining whether a problem can be solved more efficiently using a class of methods suited for nonstiff problems or a class of methods designed for stiff problems. The technique uses information that is available at the end of each step in the integration for making the decision between the two types of methods. If a problem changes character in the interval of integration, the solver automatically switches to the class of methods which is likely to be most efficient for that part of the problem. Test results, using a modified version of the LSODE package, indicate that many problems can be solved more efficiently using this scheme than with a single class of methods, and that the overhead of choosing the most efficient methods is relatively small. TS - RIS},
author = {Petzold, Linda},
doi = {10.1137/0904010},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Petzold, automatic selection of methods for solving stiff and nonstiff systems, 1983.pdf:pdf},
isbn = {0196-5204},
issn = {0196-5204},
journal = {SIAM J Sci and Stat Comput},
keywords = {1,can be solved more,class of methods,dt,efficiently using a class,f,initial value problems,introduction,nonstiff,nonstiff problems or a,of methods suited for,ordinary differential equations,problem dy,scheme for automatically determining,stiff,t,this paper describes a,to,whether an initial value,y,yo},
number = {1},
pages = {136--148},
title = {{Automatic selection of methods for solving stiff and nonstiff systems of ordinary differential equations}},
volume = {4},
year = {1983}
}
@article{Rickard1997,
abstract = {H2S acts as an oxidizing agent in natural systems and compares with molecular oxygen as an electron acceptor. The experimentally determined lowest unoccupied molecular orbital (LUMO) for H2S is −1.1 eV, which means that H2S can be an excellent electron acceptor. In the oxidation of Fe(II) monosulfide by H2S in aqueous solutions between 25 and 125°C, FeS+H2S(aq)=FeS2+H2(g) (where FeS is any Fe(II) monosulfide, H2S(aq) is aqueous H2S, FeS2 is pyrite and H2(g) is hydrogen gas), FeS is the electron donor (reductant) and aqueous H2S is the electron acceptor (oxidant) and the product of the oxidation is H2 gas. Because of the relative destabilization of H2S caused by the presence of an antibonding LUMO orbital in a significantly bent molecule, electrons added to this LUMO orbital cause a weakening of both SH bonds as an SS bond forms. This allows the hydrogen atoms to combine to form H2 because of their proximity and favorable interaction based on the original LUMO of H2S. The reaction is transport-controlled. The mean Arrhenius energy for the reaction is 33.7 kJ mol−1. The Arrhenius energy is temperature dependent, which is consistent with electroactive, colloidal FeS being the FeS reactant. MO calculations suggest that the reaction proceeds through a FeS → SH2 intermediate. The intermediate allows for the formation of an SS bond, the breaking of HS bonds with the formation of H2 and the conversion of Fe(II) from high to low spin. The H2 and FeS2 formed interact with adsorption of H2 onto the FeS2 surface. The reaction mechanism can be summarised 1.FeS(s)→FeS(aq)(fast{\textless}ca.100°C{\textgreater}slow)2.FeS(aq)+H2S(aq)→{\{}FeS→SH2{\}}(fast)3.{\{}FeS→SH2{\}}→[FeS2⋅H2(occluded)](fast)4.[FeS2⋅H2(occluded)]→FeS2(s)+H2(g)(slow{\textless}ca.100°C{\textgreater}fast) The product pyrite forms as mixtures of individual cubes (up to 800 nm in size) and sub-spherical aggregates up to 1400 nm in diameter (“protoframboids”) on the surface of aggregates of particulate FeS. The lack of crystal growth observed in the pyrite products through 20 days of reaction at 125°C suggests that growth is nutrient limited. Observations show that initially, pyrite nucleates on the FeS but subsequently nucleation occurs on pre-formed pyrite crystals. Nucleation is rapid and kinetically favored over crystal growth leading to no significant increase in crystal size as the reaction progresses. There is some evidence that the crystal growth mechanism is through screw dislocation growth. HS− cannot be an electron acceptor because of the high positive calculated energy for the LUMO orbital (+8.015 eV). It is not possible to write an electronically balanced redox reaction involving HS− with FeS without the presence of an additional electron acceptor. In contrast, it is possible at high pH values that the complex FeSH+ could react with HS− to form pyrite: however, the reaction is very slow and has not been observed experimentally. The net effect of these observations in natural systems is that reduced systems may change from oxidized to reduced merely by changing pH, from H2S-dominant (oxidizing) at pH {\textless} 7 to HS− dominant (reducing) at pH {\textgreater} 7.},
author = {Rickard, David and Luther, George W.},
doi = {10.1016/S0016-7037(96)00322-5},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Rickart, 1997 h2s oxidation.pdf:pdf},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
number = {1},
pages = {135--147},
title = {{Kinetics of pyrite formation by the H2S oxidation of iron (II) monosulfide in aqueous solutions between 25 and 125C: The mechanism}},
volume = {61},
year = {1997}
}
@article{Norkko1993,
abstract = {The north American polychaete species Marenzelleria viridis (Verril) is reported for the first time from Finland. Brief notes on the biology of the species are given.},
author = {Norkko, Alf and Bonsdorff, Erik and Bostr{\"{o}}m, Christoffer},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/norkko, marenzelleria observation, 1993.pdf:pdf},
journal = {Memoranda Societatis pro Fauna Flora Fennica},
pages = {112--113},
title = {{Observations of the polychaete Marenzelleria viridis (Verril) on a shallow sandy bottom on the south coast of Finland}},
volume = {69},
year = {1993}
}
@article{Froelich1988b,
abstract = {Pore water chemistry (total dissolved CO2, NH4, NO3, NO2, PO4, Si(OH)4, Ca, Mg, Fe, Mn, SO4, H2S and F, and titration alkalinity), solid phase chemistry (Corg, Porg, CTOT, NTOT, F, SiOPAL and SII), and sediment characteristics (porosity, dry bulk density and formation factors) were determined on a centimeter-scale spacing in the upper 20-40 cm of sediments under intense upwelling areas on the Peru continental shelf. These data demonstrate that carbonate fluorapatite (CFA) is precipitating from pore waters in the upper few centimeters of a gelatinous mud with high organic carbon content (up to 20{\%} Corg), very high porosity ({\textgreater} 0.96 ml cm-3) and very low dry bulk density ({\textless} 0.1 g cm-3). Dissolved phosphate concentrations at the sediment-water interface range from 20 to 100 $\mu$M, orders of magnitude higher than bottom-water concentrations, and much higher than predicted from regeneration of organic matter. The mechanism of this interfacial phosphate release is unclear, but is apparently uncoupled from carbon and nitrogen metabolism and thus may be linked either to dissolution of fish debris or to the presence of a microbial mat in surficial sediments. Fluoride is incorporated into CFA by diffusion from the overlying seawater, and carbonate ions are provided from pore-water alkalinity. Magnesium concentrations in this reaction zone are not significantly different from those of seawater, suggesting that magnesium depletion is not a necessary prerequisite for CFA precipitation. The environment of precipitation is interface-linked rather than driven by organic diagenesis of phosphorus deeper in the sediment. Most of the cores display a wide range of diagenetic characteristics below the immediate interfacial region, but almost all show the precipitation signature near the interface. This interface-linked early diagenetic porewater environment for the precipitation of CFA explains many of the geochemical characteristics of phosphorites and provides a "testable" model to compare the modern phosphogenic analog with ancient phosphorite deposits. Two of the cores display very high solid phase phosphorus and fluoride contents reflecting the presence of apparently modern pelletal apatites. {\textcopyright} 1988.},
author = {Froelich, P. N. and Arthur, M. A. and Burnett, W. C. and Deakin, M. and Hensley, V. and Jahnke, R. and Kaul, L. and Kim, K. H. and Roe, K. and Soutar, A. and Vathakanon, C.},
doi = {10.1016/0025-3227(88)90095-3},
isbn = {0025-3227},
issn = {00253227},
journal = {Marine Geology},
number = {3-4},
pages = {309--343},
pmid = {4048},
title = {{Early diagenesis of organic matter in Peru continental margin sediments: Phosphorite precipitation}},
volume = {80},
year = {1988}
}
@article{Reed2016,
abstract = {Coastal hypoxia is a growing and persistent problem largely attributable to enhanced terrestrial nutrient (i.e., nitrogen and phosphorus) loading. Recent studies suggest phosphorus removal through burial of iron (II) phosphates, putatively vivianite, plays an important role in nutrient cycling in the Baltic Sea - the world's largest anthropogenic dead zone - yet the dynamics of iron (II) phosphate formation are poorly constrained. To address this, a reactive-transport model was used to reconstruct the diagenetic and depositional history of sediments in the F{\aa}r{\"{o}} basin, a deep anoxic and sulphidic region of the Baltic Sea where iron (II) phosphates have been observed. Simulations demonstrate that transport of iron from shelf sediments to deep basins enhances vivianite formation while sulphide concentrations are low, but that pyrite forms preferentially over vivianite when sulphate reduction intensifies due to elevated organic loading. Episodic reoxygenation events, associated with major inflows of oxic waters, encourage the retention of iron oxyhydroxides and iron-bound phosphorus in sediments, increasing vivianite precipitation as a result. Results suggest that artificial reoxygenation of the Baltic Sea bottom waters could sequester up to 3{\%} of the annual external phosphorus loads as iron (II) phosphates, but this is negligible when compared to potential internal phosphorus loads due to dissolution of iron oxyhydroxides when low oxygen conditions prevail. Thus, enhancing vivianite formation through artificial reoxygenation of deep waters is not a viable engineering solution to eutrophication in the Baltic Sea. Finally, simulations suggest that regions with limited sulphate reduction and hypoxic intervals, such as eutrophic estuaries, could act as important phosphorus sinks by sequestering vivianite. This could potentially alleviate eutrophication in shelf and slope environments.},
author = {Reed, Daniel C. and Gustafsson, Bo G. and Slomp, Caroline P.},
doi = {10.1016/j.epsl.2015.11.033},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Reed, vivianite 2016.pdf:pdf},
issn = {0012821X},
journal = {Earth and Planetary Science Letters},
keywords = {Baltic Sea,Eutrophication,Iron,Phosphorus,Reactive-transport modelling,Sediment geochemistry},
pages = {241--251},
publisher = {Elsevier B.V.},
title = {{Shelf-to-basin iron shuttling enhances vivianite formation in deep Baltic Sea sediments}},
url = {http://dx.doi.org/10.1016/j.epsl.2015.11.033},
volume = {434},
year = {2016}
}
@article{Slomp1996a,
abstract = {A combination of pore water and solid phase analysis was used to determine whether authigenic carbonate fluorapatite (CFA) is currently forming in the sediment at two locations (OMEX I and II) on the North Atlantic continental platform Goban Spur (southwest of Ireland). Results of selective P extractions suggest that an early diagenetic redistribution of Fe-bound P to an authigenic P phase may be occurring at both stations. A steady-state diagenetic model describing the depth profiles of pore water HPO42- and three solid phase forms of P (organic P, Fe-bound P and authigenic P) was developed and applied to the data of station OMEX-I. The model results indicate that CFA formation can account for the observed increase of authigenic P with depth at this station. Furthermore, the results show that an intense cycling of P between Fe-bound P and pore water HPO42- at the redox interface can create conditions beneficial for CFA formation. This internal P cycle is driven by downward, bioturbational transport of mainly in-situ-formed Fe-bound P into the reduced sediment zone. Losses from the internal P cycle due to CFA formation and HPO42- diffusion are compensated for by sorption of HPO42- released from organic matter to Fe oxides in the oxidized surface sediment. Fe-bound P thus acts as an intermediate between organic P and CFA. CFA can account for between 25 and 70{\%} of the total burial flux of reactive P at station OMEX-I and thus may act as an important sink for P in this low sedimentation, continental margin environment.},
author = {Slomp, Caroline P. and Epping, Eric H. G. and Helder, Willem and Raaphorst, Wim Van},
doi = {10.1357/0022240963213745},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Slomp, apetite formation.pdf:pdf},
isbn = {0022-2402},
issn = {00222402},
journal = {Journal of Marine Research},
number = {6},
pages = {1179--1205},
title = {{A key role for iron-bound phosphorus in authigenic apatite formation in North Atlantic continental platform sediments}},
volume = {54},
year = {1996}
}
@article{Steenbergh2013,
abstract = {The stoichiometry of prokaryotes (Bacteria and Archaea) can control benthic phosphorus (P) fluxes relative to carbon (C) and nitrogen (N) during organic matter remineralization. This paper presents the first experimental data on benthic microbial stoichiometry. We used X-ray microanalysis to determine C : N : P ratios of individual prokaryotes from C-limited Baltic Sea sediments incubated under oxic or anoxic conditions. At approximately 400:1, C : P ratios of prokaryotes from both oxic and anoxic incubations were higher than the Redfield ratio for marine organic matter (106:1), whereas prokaryotic C : N ratios (6.4:1) were close to the Redfield ratio. We conclude that high microbial C : P ratios contribute to the enhanced remineralization of P from organic matter relative to C and N observed in many low oxygen marine settings.},
author = {Steenbergh, A. K. and Bodelier, P. L E and Heldal, M. and Slomp, C. P. and Laanbroek, H. J.},
doi = {10.1111/1462-2920.12042},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Steenbergh,Does microbial stoichiometry modulate eutrophicationof aquatic ecosystems,2013.pdf:pdf},
isbn = {1462-2912},
issn = {14622912},
journal = {Environmental Microbiology},
number = {5},
pages = {1572--1579},
pmid = {23227825},
title = {{Does microbial stoichiometry modulate eutrophication of aquatic ecosystems?}},
volume = {15},
year = {2013}
}
@article{Raiswell2011,
abstract = {The biogeochemical cycle of iron plays a key role in the ocean by delivering bioavailable iron that controls plankton productivity. Transport through the iron cycle occurs mainly as nanoparticulate (oxyhydr)oxides, which are physically and chemically intermediate between aqueous and particulate forms and can be directly or indirectly bioavailable. Iron nanoparticles transform with time to more stable forms by increased crystallinity, aggregation and growth, and they also alter to other nanominerals. These age transformations can be inhibited or reversed. The resulting aging-rejuvenation cycle first produces stability during long-distance transport and then reverses the process such that bioavailable and labile iron can be produced and delivered to the open ocean.},
author = {Raiswell, Robert},
doi = {10.2113/gselements.7.2.101},
isbn = {1811-5209},
issn = {18115209},
journal = {Elements},
keywords = {Estuaries,Icebergs,Iron (oxyhydr)oxide,Iron cycle,Nanoparticle,Shelf sources,Wind-blown dust},
number = {2},
pages = {101--106},
title = {{Iron transport from the continents to the open ocean: The aging-rejuvenation cycle}},
volume = {7},
year = {2011}
}
@book{Berner1980,
abstract = {Diagenesis refers to changes taking place in sediments after deposition. In a theoretical treatment of early diagenesis, Robert Berner shows how a rigorous development of the mathematical modeling of diagenetic processes can be useful to the understanding and interpretation of both experimental and field observations. His book is unique in that the models are based on quantitative rate expressions, in contrast to the qualitative descriptions that have dominated the field.},
author = {Berner, R A},
booktitle = {Princeton Series in Geochemistry},
isbn = {069108260X},
number = {1},
pages = {241},
title = {{Early Diagenesis: A Theoretical Approach}},
url = {http://books.google.com/books?id=weRFglCVBkUC{\&}pgis=1},
year = {1980}
}
@article{Andersson2006,
abstract = {Variations in the physico-chemical speciation of the rare earth elements (REE) have been investigated in a subarctic boreal river during an intense spring flood event using prefiltered ({\textless}100 $\mu$m) samples, cross-flow (ultra)filtration (CFF), flow field-flow fractionation (FlFFF), and diffusive gradients in thin films (DGT). This combination of techniques has provided new information regarding the release and transport of the REE in river water. The colloidal material can be described in terms of two fractions dominated by carbon and iron, respectively. These two fractions, termed colloidal carrier phases, showed significant temporal changes in concentration and size distribution. Before the spring flood, colloidal carbon concentrations were low, the colloids being dominated by relatively large iron colloids. Colloidal concentrations increased sharply during the spring flood, with smaller carbon colloids dominating. Following the spring flood, colloidal concentrations decreased again, smaller carbon colloids still dominating. The REE are transported mainly in the particulate and colloidal phases. Before the spring flood, the REE composition of all measured fractions was similar to local till. During the spring flood, the REE concentrations in the colloidal and particulate fractions increased. The increase was most marked for the lighter REE, which therefore showed a strong enrichment when normalized to local till. Following the spring flood, the REE concentrations decreased again and reverted to a distribution similar to local till. These changes in the concentration and distributions of carbon iron and REE are interpreted in terms of changing hydrological flow paths in soil and bedrock which occur during the spring flood. {\textcopyright} 2006 Elsevier Inc. All rights reserved.},
author = {Andersson, Karen and Dahlqvist, Ralf and Turner, David and Stolpe, Bj{\"{o}}rn and Larsson, Tobias and Ingri, Johan and Andersson, Per},
doi = {10.1016/j.gca.2006.04.021},
isbn = {00167037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
number = {13},
pages = {3261--3274},
title = {{Colloidal rare earth elements in a boreal river: Changing sources and distributions during the spring flood}},
volume = {70},
year = {2006}
}
@book{Boudreau1997,
abstract = {The study of sedimentary chemistry and its associated processes is becoming increasingly mathematical. There is a growing desire to gain a quantitative understand of the reasons for the natural chemical changes observed in sediments as they are buried. Past textbooks have not emphasized the steps necessary to develop transport-reaction (diagenetic) models themselves nor methods for their solution. This book attempts to present a detailed account of model formulation by explaining some useful solution techniques. The choice of material illustrates methods that are simple to understand and implement, yet powerful enough to attack even the most complicated diagenetic problems. The cited computer programs are accessible on the Internet.},
author = {Boudreau, Bernard P.},
booktitle = {Springer, New York},
doi = {0.I007/97S-3-642-60421-S},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Boudreau, Diagenetic Models and their Implementation.pdf:pdf},
isbn = {9783642643996},
issn = {02648172},
number = {November},
pages = {49--66},
title = {{Diagenetic models and their implementation. Modelling transport and reactions in aquatic sediments}},
volume = {171},
year = {1997}
}
@article{Ettwig2016,
author = {Ettwig, Katharina F. and Zhu, Baoli and Speth, Daan and Keltjens, Jan T. and Jetten, Mike S. M. and Kartal, Boran},
doi = {10.1073/pnas.1609534113},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Ettwig, Fe-AOM archaea, PNAS 2016.pdf:pdf},
issn = {0027-8424},
journal = {Proceedings of the National Academy of Sciences},
pages = {201609534},
title = {{Archaea catalyze iron-dependent anaerobic oxidation of methane}},
url = {http://www.pnas.org/lookup/doi/10.1073/pnas.1609534113},
year = {2016}
}
@article{Froelich1988a,
abstract = {The primary mode of interaction of dissolved phosphate with fluvial inorganic suspended par- ticles is via a reversible two-step sorption process. The first step, adsorption/desorption on surfaces, has fast kinetics (minutes-hours). The second step, solid-state diffusion of adsorbed phosphate from the surface into the interior of particles, has slow kinetics (days-months) and is dependent on the time history of the previous surface sorption and the chemistry of the solid diffusional layer. Natural clay particles with a surficial armoring of reactive iron and aluminum hydroxyoxides resulting from chemical weathering of rocks and soils have a high capacity for absorbing phosphate in the second step and for maintaining low "equilibrium phosphate concentrations" in solution. Extrapolation of laboratory sorption and extraction experiments with natural soils and suspended sediments to the environment suggests that the phosphate concentrations of unperturbed turbid rivers (SPM {\textgreater}50 mg liter-') are controlled near the dynamic equilibrium phosphate concentration of their particles (EPCO = 0.2-1.5 ,uM) and that fluvial suspended particles "at equilibrium" contain up to 10 ,umol-P g-' that is desorbable. Release of this phosphate from particles entering the sea produces the characteristic shape and magnitude of input profiles of dissolved phosphate observed in unperturbed estuaries. On a global scale, fluvial particulates could transport from 1.4 to 14 x 10'? mol yr-' of reactive phosphate to the sea, some 2-5 times more than that in the dissolved load alone.},
author = {Froelich, Philip N.},
doi = {10.2307/2837216},
isbn = {00243590},
issn = {0024-3590},
journal = {Limnology and Oceanography},
number = {4, Part 2},
pages = {649--668},
pmid = {389},
title = {{Kinetic control of dissolved phosphate in natural rivers and estuaries: A primer on the phosphate buffer mechanism}},
volume = {33},
year = {1988}
}
@article{Ruttenberg1992,
abstract = {A sequential extraction method (SEDEX) has been developed to separately quantify five sedi- mentary P reservoirs: loosely sorbed P; ferric iron-bound P, authigenic carbonate fluorapatite + biogenic apatite + CaCO,-associated P; detrital apatite P; and organic P. The SEDEX method successfully separates two of the main categories of authigenic phosphate phases called upon most often as sedimentary sinks for diagenetically mobilized I? ferric oxyhydroxide-associated P and authigenic carbonate fluorapatite (CFAP). It offers a means for separating authigenic CFAP from detrital apatite of igneous or metamorphic origin. The importance of this distinction is that CFAP represents an oceanic sink for reactive P, whereas detrital apatite does not. In addition, a means for reversing secondary adsorption of P onto residual solid surfaces during extraction has been developed. Extensive standardization of the SEDEX method for application to marine sediments has been performed with analogs for naturally occurring phosphatic phases. To},
author = {Ruttenberg, Kathleen C},
doi = {10.4319/lo.1992.37.7.1460},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Methods/Extractions/Phosphate/Ruttenberg, SEDEX.pdf:pdf},
isbn = {0024-3590},
issn = {00243590},
journal = {Limnology and Oceanography},
number = {7},
pages = {1460--1482},
pmid = {588},
title = {{Development of a sequential extraction method for different forms of phosphorus in marine sediments}},
volume = {37},
year = {1992}
}
@article{Holemann2005,
abstract = {The distribution of dissolved and particulate trace metals (Fe, Mn, Cu, Ni, Zn, and Pb) was studied for the first time during the spring high flow period of the Lena River (Arctic Siberia). The results show that concentrations of dissolved metals in the river Lena during the spring high flow in June 1996 (spring freshet) were significantly higher than those reported for the rest of the year. For example the measured average concentration of dissolved Fe (6349 ± 2122 nM) during the high flow is approximately 7 times higher than previously published concentrations measured during the summer months. Dissolved Fe concentrations in the freshwater (salinity {\textless} 1) are positively correlated with the amount of suspended particulate matter (SPM) (p {\textless} 0.01), but negatively correlated with the Fe concentrations in SPM (p {\textless} 0.01). The data showed that the aluminium-normalized concentrations of particulate Fe, Mn, Pb, Ni, and Zn in the freshwater are negatively correlated with SPM. This suggests that the mobilization of metals from suspended particulate matter is the driving force for the observed high concentrations of dissolved Fe, Mn, Zn and Pb in the water of the Lena River during the spring freshet. During the high flow period in June about 35{\%} of the total annual flow of the river Lena flows into the Laptev Sea. Previously published metal budgets for the river Lena that did not incorporate data from the spring high flow period, therefore, underestimate the fluxes of dissolved trace metals from the Siberian rivers to the Arctic Ocean. For instance, the estimated input of dissolved Fe in June 1996 is approximately 4.5 times higher than the average annual dissolved Fe input calculated on the basis of summer data. The results of this study demonstrate that the previous evaluations of the trace metal flux of the Lena river-which are based on data obtained from August to October-may underestimate the total riverine input of dissolved trace metals to the Arctic Ocean. {\textcopyright} 2005 Elsevier B.V. All rights reserved.},
author = {H{\"{o}}lemann, J. A. and Schirmacher, M. and Prange, A.},
doi = {10.1016/j.gloplacha.2004.12.008},
isbn = {0921-8181},
issn = {09218181},
journal = {Global and Planetary Change},
keywords = {Arctic,Laptev Sea,Lena River,Seasonal variability,Trace elements},
number = {1-3 SPEC. ISS.},
pages = {112--125},
title = {{Seasonal variability of trace metals in the Lena River and the southeastern Laptev Sea: Impact of the spring freshet}},
volume = {48},
year = {2005}
}
@article{Martens1978,
abstract = {The stoichiometry of nutrient regeneration in anoxic Long Island Sound sediments is examined through changes in the concentration of dissolved sulfate, ammonia, reactive phosphate, and other chemical species with depth in interstitial waters. In offshore sediments the mean {\^{I}}” SO4: {\^{I}}” NH4:{\^{I}}” {\^{a}}ˆ‘ P ratio is -53:4.6:0.37; in shallow harbor sediment it is -53:19:3.3 and {\^{I}}” NH4:{\^{I}}” {\^{a}}ˆ‘ P ratios are half the offshore ratio. These indicated shoreward changes probably reflect more rapid deposition, and thus less preferential stripping of P and N from organic material before burial in shallow water harbor sediments, or selective stripping in the heavily bioturbated upper sediment layers offshore, or both. The effects of differential diffusion and adsorption of ammonia and phosphorus are considered. Phosphate concentration maxima in ammonia-and phosphate-rich shallow harbor sediments yield evidence for possible equilibrium with respect to vivianite, FE3(PO4)2{\^{A}}{\textperiodcentered} 8H2O, and struvite, MgNH4PO 4{\^{A}}{\textperiodcentered} 6H2O.},
author = {Martens, Christopher S. and Berner, Robert A. and Rosenfeld, Jeffrey K.},
doi = {10.4319/lo.1978.23.4.0605},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Martens, nterstitial water chemistry of anoxic Long Island Sound, 1978.pdf:pdf},
isbn = {00243590},
issn = {00243590},
journal = {Limnology and Oceanography},
number = {4},
pages = {605--617},
title = {{Interstitial water chemistry of anoxic Long Island Sound sediments. 2. Nutrient regeneration and phosphate removal}},
volume = {23},
year = {1978}
}
@book{Burdige2006,
abstract = {The processes occurring in surface marine sediments have a profound effect on the local and global cycling of many elements. This graduate text presents the fundamentals of marine sediment geochemistry by examining the complex chemical, biological, and physical processes that contribute to the conversion of these sediments to rock, a process known as early diagenesis. Research over the past three decades has uncovered the fact that the oxidation of organic matter deposited in sediment acts as a causative agent for many early diagenetic changes. Summarizing and discussing these findings and providing a much-needed update to Robert Berner'sEarly Diagenesis: A Theoretical Approach, David J. Burdige describes the ways to quantify geochemical processes in marine sediment. By doing so, he offers a deeper understanding of the cycling of elements such as carbon, nitrogen, and phosphorus, along with important metals such as iron and manganese. No other book presents such an in-depth look at marine sediment geochemistry. Including the most up-to-date research, a complete survey of the subject, explanatory text, and the most recent mathematical formulations that have contributed to our greater understanding of early diagenesis,Geochemistry of Marine Sedimentswill interest graduate students of geology, geochemistry, and oceanography, as well as the broader community of earth scientists. It is poised to become the standard text on the subject for years to come.},
author = {Burdige, David J.},
booktitle = {Princeton University Press},
doi = {10.1086/533614},
isbn = {0-691-09506-X},
issn = {0022-1376},
pages = {208--209},
title = {{Geochemistry of Marine Sediments}},
year = {2006}
}
@article{Berner1984,
abstract = {Sedimentary pyrite formation during early diagenesis is a major process for controlling the oxygen level of the atmosphere and the sulfate concentration in seawater over geologic time. The amount of pyrite that may form in a sediment is limited by the rates of supply of decomposable organic matter, dissolved sulfate, and reactive detrital iron minerals. Organic matter appears to be the major control on pyrite formation in normal (non-euxinic) terrigenous marine sediments where dissolved sulfate and iron minerals are abundant. By contrast, pyrite formation in non-marine, freshwater sediments is severely limited by low concentrations of sulfate and this characteristic can be used to distinguish ancient organic-rich fresh water shales from marine shales. Under marine euxinic conditions sufficient H2S is produced that the dominant control on pyrite formation is the availability of reactive iron minerals. Calculations, based on a sulfur isotope model, indicate that over Phanerozoic time the worldwide average organic carbon-to-pyrite sulfur ratio of sedimentary rocks has varied considerably. High C S ratios during Permo-Carboniferous time can be explained by a shift of major organic deposition from the oceans to the land which resulted in the formation of vast coal swamps at that time. Low C S ratios, compared to today, during the early Paleozoic can be explained in terms of a greater abundance of euxinic basins combined with deposition of a more reactive type of organic matter in the remaining oxygenated portions of the ocean. The latter could have been due to lower oceanic oxygen levels and/or a lack of transportation of refractory terrestrial organic matter to the marine environment due to the absence of vascular land plants at that time. {\textcopyright} 1984.},
author = {Berner, Robert A.},
doi = {10.1016/0016-7037(84)90089-9},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
number = {4},
pages = {605--615},
pmid = {4163},
title = {{Sedimentary pyrite formation: An update}},
volume = {48},
year = {1984}
}
@article{Rue1995,
abstract = {A highly sensitive voltammetric technique was developed to examine Fe speciation in seawater. The technique involves adding an Fe(III)-complexing ligand, salicylaldoxime, which competitively equilibrates with inorganic and organic Fe(III) species in ambient seawater. The Fe(III)-salicylaldoxime complex then is measured by adsorptive cathodic stripping voltammetry (ACSV). This new method revealed that 99.97{\%} of the dissolved Fe(III) in central North Pacific surface waters is chelated by natural organic ligands. The total concentration of Fe-binding ligands is approximately 2 nM, a value greatly in excess of ambient dissolved iron concentrations. The titration data can be modeled as consisting of two classes of Fe-binding ligands, a strong ligand class (L1) with an average surface-water concentration equal to 0.44 nM with a conditional stability constant KL1 Fe???cond = 1.2 ?? 1013 M-1, and a weaker ligand class (L2) with an average concentration equal to 1.5 nM with KL2 Fe???cond = 3.0 ?? 1011 M-1. The low concentration of dissolved Fe present in surface waters ({\~{}} 0.2 nM), coupled with the excess of strong Fe-chelators, results in extremely low equilibrium concentrations of dissolved inorganic iron, [Fe???] ??? 0.07 pM. In the deeper waters there is a 2 nM excess of Fe-binding ligands with a stability constant similar to that of the L2 class of ligands observed in surface waters, resulting in dissolved Fe(III) existing primarily in the chelated form in deep waters as well. The stability constants of the natural ligands are comparable to the model ligands desferal, a siderophore, and the prosthetic heme group, protoporphyrin-IX. The high degree of organic complexation of iron makes it critically important to reevaluate our perceptions of the marine biogeochemistry of iron and the mechanisms by which biota can access this chelated Fe. ?? 1995.},
author = {Rue, Eden L. and Bruland, Kenneth W.},
doi = {10.1016/0304-4203(95)00031-L},
isbn = {0304-4203},
issn = {03044203},
journal = {Marine Chemistry},
number = {1-4},
pages = {117--138},
title = {{Complexation of iron(III) by natural organic ligands in the Central North Pacific as determined by a new competitive ligand equilibration/adsorptive cathodic stripping voltammetric method}},
volume = {50},
year = {1995}
}
@article{Savchuk2005,
abstract = {Total nitrogen and phosphorus budgets based on more than 32,000 oceanographic stations have been constructed for the first time for all seven major marine basins within the Baltic Sea, including the Kattegat. The budgeted time interval, 1991-1999, comprises both extreme and more typical states of the Baltic Sea. The budgets were compared with published independent estimates of water flows and biogeochemical fluxes to ensure consistency. The budgets show that the Baltic Sea annually exported to Skagerrak masses of nutrients equivalent to 15{\%} of nitrogen and 45{\%} of phosphorus inputs from land and atmosphere during the period studied. The high phosphorus export during this decade is explained by an internal phosphorus source in the Baltic Proper of 18,000 tons released annually from anoxic sediments. A network flow analysis, which demonstrates how changing the loads to each individual basin changes the total nutrient inputs into all basins, indicates that the Baltic Proper is more susceptible to such changes than any other subbasin of the Baltic. {\textcopyright} 2004 Elsevier B.V. All rights reserved.},
author = {Savchuk, Oleg P.},
doi = {10.1016/j.jmarsys.2004.08.005},
isbn = {0924-7963},
issn = {09247963},
journal = {Journal of Marine Systems},
keywords = {Baltic Sea,Biogeochemical budgets,Network analyses,Nitrogen,Phosphorus},
number = {1-2},
pages = {1--15},
title = {{Resolving the Baltic Sea into seven subbasins: N and P budgets for 1991-1999}},
volume = {56},
year = {2005}
}
@misc{Cappellen1988,
author = {Cappellen, P. V. and Berner, R. A.},
booktitle = {American Journal of Science},
doi = {10.2475/ajs.288.4.289},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/van cappellen, A mathematical model for the early diagenesis of phosphorus and fluorine in marine sediments$\backslash$; apatite precipitation, 1988.pdf:pdf},
issn = {00029599},
number = {4},
pages = {289--333},
title = {{A mathematical model for the early diagenesis of phosphorus and fluorine in marine sediments: apatite precipitation}},
volume = {288},
year = {1988}
}
@article{Kauppi2015,
abstract = {Invasive species are considered to be a major threat to both terrestrial and aquatic ecosystems worldwide due to their negative effects on biodiversity, ecosystem functioning and species interactions. This study investigates with the help of large-scale monitoring datasets the spatial and temporal distribution of a successful invader, the polychaete species complex Marenzelleria spp. Mesnil 1896 into a species-poor, brackish water ecosystem in northern Europe, the Baltic Sea. The species complex has spread throughout the entire Baltic Sea and has become a dominant member of the communities especially in deeper, hypoxia-affected areas. The dynamics of the invasion follow a boom-and-bust pattern, with abundances peaking almost simultaneously throughout the Baltic Sea in 2005–2006. Possible mechanisms behind the successful establishment are changes in hydrography and species composition. Hypothesized and observed ecological impacts are reviewed. Evidence suggests a multitude of potential, sometimes contrasting, impacts. Due to the widespread distribution and high abundances, the biology and ecology of Marenzelleria spp. in the Baltic Sea need to be investigated further in order to assess its impact on ecosystem structure and functioning.},
author = {Kauppi, Laura and Norkko, Alf and Norkko, Joanna},
doi = {10.1007/s10530-015-0860-0},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Kauppi, marenzelleria, 2015.pdf:pdf},
isbn = {1387-3547
1573-1464},
issn = {13873547},
journal = {Biological Invasions},
keywords = {Dominance,Habitat degradation,Hypoxia,Soft-sediment communities,Spionid polychaete},
number = {7},
pages = {2055--2074},
publisher = {Springer International Publishing},
title = {{Large-scale species invasion into a low-diversity system: spatial and temporal distribution of the invasive polychaetes Marenzelleria spp. in the Baltic Sea}},
url = {http://dx.doi.org/10.1007/s10530-015-0860-0},
volume = {17},
year = {2015}
}
@article{Ingall1993,
abstract = {Organic P and organic C concentrations were measured in several well-characterized Phanerozoic marine shale sequences with the primary focus being the Camp Run Member of the Devonian-Mississippian New Albany Shale. Sequences were selected with close spatial association of bioturbated and laminated sediments which reflect deposition from oxic and anoxic waters, respectively. Average organic C/P mole ratios calculated from the data are 150 for bioturbated shales and 3900 for the laminated shales of the New Albany. Differences in the extent and mechanisms of early diagenesis related to the oxygenation of waters at the sediment-water interface can account for the C/P ratios of buried organic matter. Low C/P ratios of bioturbated sediments are attributed to 1. (1) the increased ability of bacteria to store P in well-oxygenated environments which leads to the production of low C/P ratio bacterial biomass and 2. (2) the extensive oxidation of sedimentary organic matter resulting in the formation of residual organic phases with low C/P ratios. High organic C/P ratios of laminated sediments are explained by a combination of 1. (1) the limited ability of bacteria to store P under anoxic conditions, 2. (2) extensive P regeneration from sedimentary organic matter, 3. (3) enhanced C preservation relative to the bioturbated shales. It is also shown that relative to organic C, laminated shales are not as effective a P sink as are bioturbated shales. This provides a mechanism in anoxic environments for burying large quantities of organic matter without simultaneously sequestering the P needed to sustain further productivity. ?? 1993.},
author = {Ingall, Ellery D. and Bustin, R. M. and {Van Cappellen}, Philippe},
doi = {10.1016/0016-7037(93)90433-W},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Ingall, Influence ofwater column anoxia on the burial and preservation of carbon and phosphorus in marine shales., 1993.pdf:pdf},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
number = {2},
pages = {303--316},
pmid = {29993},
title = {{Influence of water column anoxia on the burial and preservation of carbon and phosphorus in marine shales}},
volume = {57},
year = {1993}
}
@article{Kraal2014,
abstract = {The chemical forms of phosphorus (P) in sediments are routinely measured in studies of P in modern and ancient marine environments. However, samples for such analyses are often exposed to atmospheric oxygen during storage and handling. Recent work suggests that long-term exposure of pyrite-bearing sediments can lead to a decline in apatite P and an increase in ferric Fe-bound P. Here, we report on alterations in P speciation in reducing modern Baltic Sea sediments that we deliberately exposed to atmospheric oxygen for a period of either one week or one year. During oxidation of the sediment, extensive changes occurred in all measured P reservoirs. Exchangeable P all but disappeared during the first week of exposure, likely reflecting adsorption of porewater PO4 by Fe(III) (oxyhydr)oxides (i.e. ferric Fe-bound P formation). Detrital and organic P were also rapidly affected: decreases in both reservoirs were already observed after the first week of exposure to atmospheric oxygen. This was likely because of acidic dissolution of detrital apatite and oxidation of organic matter, respectively. These processes produced dissolved PO4 that was then scavenged by Fe(III) (oxyhydr)oxides. Interestingly, P in authigenic calcium phosphates (i.e. apatite: authigenic Ca-P) remained unaffected after the first week of exposure, which we attributed to the shielding effect of microfossils in which authigenic Ca-P occurs in Baltic Sea sediments. This effect was transient; a marked decrease in the authigenic Ca-P pool was observed in the sediments after one year of exposure to oxygen. In summary, we show that handling and storage of wet sediments under oxic conditions can lead to rapid and extensive alteration of the original sediment P speciation.},
author = {Kraal, Peter and Slomp, Caroline P.},
doi = {10.1371/journal.pone.0096859},
isbn = {10.1371/journal.pone.0096859},
issn = {19326203},
journal = {PLoS ONE},
number = {5},
pmid = {24802813},
title = {{Rapid and extensive alteration of phosphorus speciation during oxic storage of wet sediment samples}},
volume = {9},
year = {2014}
}
@article{Sarkkola2013,
abstract = {Observations of increased water colour have been made in lakes and rivers all across the northern mid-latitudes of Europe and North America, particularly during the last 10-20yr. This water browning or brownification has been attributed to the increased organic carbon concentrations due to climate change and decreased acid atmospheric deposition. Given that iron (Fe) may also increase water colour, the contribution of Fe to water brownification has received small attention. Our aim was to study the temporal trends of Fe in forested headwater catchments in eastern Finland, where an increasing air temperature and total organic carbon (TOC) trend had been observed in an earlier study. We found a statistically significant increasing trend also in stream water Fe concentrations and a strong correlation between the trends of TOC and Fe. The average increase in TOC and Fe concentrations between 1995 and 2006 was 0.5mgl-1yr-1 (2.5{\%}), and 34.6??gl-1yr-1 (3.5{\%}), respectively. These results indicate that the increased water colour or brownification in Northern Europe may not only be due to increased concentrations of organic matter but also increased concentrations of Fe. The change in precipitation and temperature conditions, particularly during late autumn and early winter periods, appeared to be the main environmental factor behind increasing Fe trends. The strong correlation between the trends of Fe and TOC indicated that the increased Fe-organic matter complexation is the mechanism behind increasing Fe trends, but further research is needed to assess the chemical forms of increased Fe that coupled with increased TOC concentrations would enhance water brownification. ?? 2013 Elsevier B.V.},
author = {Sarkkola, Sakari and Nieminen, Mika and Koivusalo, Harri and Lauren, Ari and Kortelainen, Pirkko and Mattsson, Tuija and Palviainen, Marjo and Piirainen, Sirpa and Starr, Mike and Finer, Leena},
doi = {10.1016/j.scitotenv.2013.06.072},
issn = {00489697},
journal = {Science of the Total Environment},
keywords = {Brownification,Fe concentration,Peatland,TOC concentration,Time series,Trend analysis},
pages = {683--689},
pmid = {23850658},
title = {{Iron concentrations are increasing in surface waters from forested headwater catchments in eastern Finland}},
volume = {463-464},
year = {2013}
}
@article{Gachter2003,
abstract = {In order to improve the trophic state of Lake Sempach, a eutrophied lake in central Switzerland, its external phosphorus (P) load has been decreased and its hypolimnion has been artificially oxygenated to lower the lake-internal P recycling. Based on more than 15 yr of experience, we conclude that the reduction of the external P load resulted in a corresponding decrease of the lake's P concentration. However, contrary to initial expectations, increased hypolimnetic dissolved oxygen concentrations neither (1) reduced the P release from sediments during summer nor (2) resulted in an increased permanent P retention. These observations warrant a reevaluation of the well-accepted management strategy of decreasing the lake internal P cycling by maintaining an aerobic hypolimnion and sediment surface. We hypothesize that oxygenation only results in an increased permanent benthic P burial if, because of the depressed sulfide production, more ferrous phosphate (e.g., vivianite) and less FeS is deposited in the anoxic sediment. Hence, it is not the oxic sediment surface that directly affects the permanent redox-dependent sediment P retention but the molar ratio of the available reactive Fe(II) S2-: PO4 in the anoxic sediment. This ratio is driven by the settling rate and the nature of organic matter and particulate iron, as well as the supply of oxygen, nitrate, and sulfate to the sediment.},
author = {G{\"{a}}chter, Ren{\'{e}} and M{\"{u}}ller, Beat},
doi = {10.4319/lo.2003.48.2.0929},
isbn = {0024-3590},
issn = {00243590},
journal = {Limnology and Oceanography},
number = {2},
pages = {929--933},
pmid = {829},
title = {{Why the phosphorus retention of lakes does not necessarily depend on the oxygen supply to their sediment surface}},
volume = {48},
year = {2003}
}
@incollection{Schwertmann1989,
abstract = {The iron oxides (embracing oxides, oxyhydroxides, and hydrated oxides) are the most abundant of the metallic oxides in soils. They are present in most soils of the different climatic regions as very fine particles in one or more of their mineral forms and at variable levels of concentration. They may occur evenly dispersed throughout the soil in horizons with a friable or loose consistency, or concentrated in discrete horizons or in particular morphological features as in ferricretes, mottles, nodules, pipestems, etc.$\backslash$nThe many different mineral phases previously have been referred to i as "free iron oxides" in an attempt to differentiate between true oxides and the Fe bound in other minerals such as the silicates. This distinction is unnecessary, since Fe in other minerals is not really present as an oxide; therefore, it will be more meaningful to refer to the minerals collectively as "iron oxides," and to subsequently distinguish prime and secondary-or pedogenic-forms.$\backslash$nPedog�nic Fe-oxide minerals form under the influence of the com-mon soil-forming factors (temperature, moisture, pH, Eh, etc), and there-fore reflect the pedoenvironmental conditions under which they have formed. Once formed, the mineral phases, composition, and distribution of Fe oxides may be subject to continual modification in an approach toward equilibrium with the changing soil environment.$\backslash$nEven at low concentrations in a soil, Fe oxides have a high pigmenting power and determine the color of many soils. Thus, yellow, brown, and red soil colors, as determined by the type and distribution of Fe oxides within a profile, help explain soil genesis and are used in all languages for naming and classifying soils (e.g., Red-Yellow Podzolic, Braunerde, sols rouges tropicaux, terra rossa, krasnozem, etc.).The chemical nature and high specific surface area of submicroscopic Fe-oxide particles make them efficient sorbents and therefore sinks for (i) inorganic anions such as silicate, phosphate, and molybdate; (ii) or-ganic anions and molecules such as citrate, fulvic and humic acids, and biocides; and (iii) cations such as Al, Cu, Pb, V, Zn, Co, Cr, and Ni, some of which are essential for plant growth. The cations can be adsorbed on the surface or incorporated into the oxide structure. Iron oxides also affect soil structure, often inducing the formation of aggregates and the cementation of other major soil components, giving rise to nodules, pipestems, plinthites, ortsteins, bog iron ores, etc.$\backslash$nFrom this short introduction, which briefly illustrates the manifold significance of Fe oxides in soils, it can be concluded that a thorough understanding of these oxide minerals will enable us to better understand the genesis of many soils and their behaviors as plant growth mediums and material resources.},
author = {Schwertmann, U and Taylor, R M},
booktitle = {Minerals in Soil Environments},
doi = {10.2136/sssabookser1.2ed.c8},
isbn = {978-0-89118-860-5},
keywords = {Iron oxide,Soil,environment},
number = {8},
pages = {379--438},
title = {{Iron Oxides}},
year = {1989}
}
@misc{Boudreau1996b,
abstract = {Use of Fick's First Law to estimate solute fluxes is arguably the most common and important calculation related to the geochemistry and environmental chemistry of fine-grained unlithified sediments. In such porous media, the diffusion coefficient in this law must be reduced by the square of the tortuosity to account for the longer diffusive paths. Experimental methods to estimate tortuosity are specialized or time consuming, and not routinely done. An analysis of available data shows that tortuosity, ??, is accurately correlated to readily measured porosity values, ??, through the simple relation: ??2 = 1 - ln(??2).},
author = {Boudreau, Bernard P.},
booktitle = {Geochimica et Cosmochimica Acta},
doi = {10.1016/0016-7037(96)00158-5},
isbn = {0016-7037},
issn = {00167037},
number = {16},
pages = {3139--3142},
title = {{The diffusive tortuosity of fine-grained unlithified sediments}},
volume = {60},
year = {1996}
}
@article{Schlitzer2015,
author = {Schlitzer, R},
journal = {Available: http://odv. awi. de. Accepted on October},
title = {{Ocean Data View. 2012}},
year = {2015}
}
@article{Glud2008,
abstract = {Benthic O-2 availability regulates many important biogeochemical processes and has crucial implications for the biology and ecology of benthic communities. Further, the benthic O-2 exchange rate represents the most widely used proxy for quantifying mineralization and primary production of marine sediments. Consequently, numerous researchers have investigated the benthic O-2 dynamics in a wide range of environments. On the basis of case studies - from abyssal sediments to microbial phototrophic communities - I hereby try to review the current status on what we know about controls that interrelate with the O-2 dynamics of marine sediments. This includes factors like: sedimentation rates, bottom water O-2 concentrations, diffusive boundary layers, fauna activity, light, temperature, and sediment permeability. The investigation of benthic O-2 dynamics represents a challenge in resolving variations on temporal and spatial scales covering several orders of magnitude. Such an effort requires the use of several complementary measuring techniques and modeling approaches. Recent technical developments (improved chamber approaches, O-2 optodes, eddy-correlation, benthic observatories) and advances in diagenetic modeling have facilitated our abilities to resolve and interpret benthic O-2 dynamics. However, all approaches have limitations and caveats that must be carefully evaluated during data interpretation. Much has been learned during the last decades but there are still many unanswered questions that need to be addressed in order to fully understand benthic O-2 dynamics and the role of sediments for marine carbon cycling.},
author = {{R. N. Glud}},
doi = {Doi 10.1080/17451000801888726},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Glud, Oxygen dynamics of marine sediments, 2008.pdf:pdf},
isbn = {1745-1000},
issn = {1745-1000},
journal = {Marine Biology Research},
keywords = {australian estuary brunswick,benthic carbon mineralization,benthic mineralization,benthic photosynthesis,biogeochemistry,deep-sea sediments,diffusive boundary-layer,eastern north pacific,european continental-margin,in situ,in-situ measurements,lander technology,microsensors,particulate organic-matter,photosynthesis-coupled respiration,planar optodes,star amphiura-filiformis},
number = {4},
pages = {243--289},
title = {{Oxygen dynamics of marine sediments}},
volume = {4},
year = {2008}
}
@article{Tamminen2007,
abstract = {The in situ P versus N limitation of northern Baltic Sea phytoplankton was studied over 3 seasonal cycles at 6 locations, encompassing the large-scale salinity and eutrophy gradients of the Baltic Sea. Limitation patterns were inferred from 170 time-series (3 d) experiments with a replicated factorial experimental design, analyzed using a novel model selection-based classification. Seven limitation classes describe exclusive and primary limitation by N, P, combined N and P, or none. Response parameters were chlorophyll a (chl a) and primary productivity. Although chl a responses reported more N-limited, and 14C responses more P-limited cases, the responses of both parameters were highly similar. Distinct seasonal patterns of in situ P versus N limitation were evident, reproducible, and dissimilar even in closely related environments. The most pristine low-saline areas were dominantly P-limited, while more eutrophied areas showed predominant N limitation even at comparable salinities. The typical Baltic Sea surface salinity regions (5 to 6 PSU) were clearly N-limited either for summer months (e.g. the mildly eutrophied Bothnian Sea), or throughout the growth season (e.g. the eutrophied Gulf of Finland), although terrestrial loading ratios for the Baltic Sea exceed the Redfield ratio several-fold. The commonly vigorous N 2-fixing cyanobacterial blooms in the southern basins do not alleviate the basic N-limitation pattern, and do not appear in the summertime N-limited Bothnian Sea. Management strategies should include toning down the N-limited spring bloom in eutrophied areas, which fuels summertime P release from sediments, in turn favoring cyanobacteria. Terrestrial nutrient loading does not reach offshore areas without significant modification and loss, emphasizing the role of coastal zones in global nutrient cycles and stoichiometry. ¬{\textcopyright} Inter-Research 2007.},
author = {Tamminen, Timo and Andersen, Tom},
doi = {10.3354/meps340121},
isbn = {0171-8630},
issn = {01718630},
journal = {Marine Ecology Progress Series},
keywords = {Baltic Sea,Bioassays,Coastal eutrophication,Nitrogen,Nutrient limitation,Phosphorus,Phytoplankton},
pages = {121--138},
pmid = {1104},
title = {{Seasonal phytoplankton nutrient limitation patterns as revealed by bioassays over Baltic Sea gradients of salinity and eutrophication}},
volume = {340},
year = {2007}
}
@article{Kritzberg2012,
abstract = {Browning of inland waters has been noted over large parts of the Northern hemisphere and is a phenomenon with both ecological and societal consequences. The increase in water color is generally ascribed to increasing concentrations of dissolved organic matter of terrestrial origin. However, oftentimes the increase in water color is larger than that of organic matter, implying that changes in the concentration of organic matter alone cannot explain the enhanced water color. Water color is known to be affected also by the quality of organic matter and the prevalence of iron. Here we investigated trends in water color, organic matter and iron between 1972 and 2010 in 30 rivers draining into the Swedish coast (data from the national Swedish monitoring program), and performed a laboratory iron addition experiment to natural waters, to evaluate the role of iron and organic matter in determining water color. By comparing the effect of iron additions on water color in the experiment, to variation in water color and iron concentration in the monitoring data, we show that iron can explain a significant share of the variation in water color (on average 25 {\%}), especially in the rivers in the north of Sweden (up to 74 {\%}). Furthermore, positive trends for iron are seen in 27 of 30 rivers (21–468 {\%}) and the increase in iron is larger than that of organic matter, indicating that iron and organic matter concentrations are controlled by similar but not identical processes. We speculate that increasing iron concentrations can be caused by changes in redox conditions, that mean that more anoxic water with high concentrations of soluble FeII are feeding into the surface waters. More studies are needed about why iron is increasing so strongly, since both causes and consequences are partly different from those of increasing organic matter content.},
author = {Kritzberg, E. S. and Ekstr{\"{o}}m, S. M.},
doi = {10.5194/bg-9-1465-2012},
isbn = {1726-4170},
issn = {17264170},
journal = {Biogeosciences},
number = {4},
pages = {1465--1478},
title = {{Increasing iron concentrations in surface waters - A factor behind brownification?}},
volume = {9},
year = {2012}
}
@article{Slomp1993,
author = {Slomp, C P and {Van Raaphorst}, W},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Slomp, Phosphate adsorption in oxidized marine sediments , 1993.pdf:pdf},
journal = {Chemical Geology},
keywords = {sorption; goethite},
number = {3-4},
pages = {477--480},
title = {{Phosphate Adsorption in Oxidized Marine-Sediments}},
volume = {107},
year = {1993}
}
@article{Jilbert2011,
abstract = {Patterns of regeneration and burial of phosphorus (P) in the Baltic Sea are strongly dependent on redox conditions. Redox varies spatially along water depth gradients and temporally in response to the seasonal cycle and multidecadal hydrographic variability. Alongside the well-documented link between iron oxyhydroxide dissolution and release of P from Baltic Sea sediments, we show that preferential remineralization of P with respect to carbon (C) and nitrogen (N) during degradation of organic matter plays a key role in determining the surplus of bioavailable P in the water column. Preferential remineralization of P takes place both in the water column and upper sediments and its rate is shown to be redox-dependent, increasing as reducing conditions become more severe at greater water-depth in the deep basins. Existing Redfield-based biogeochemical models of the Baltic may therefore underestimate the imbalance between N and P availability for primary production, and hence the vulnerability of the Baltic to sustained eutrophication via the fixation of atmospheric N. However, burial of organic P is also shown to increase during multidecadal intervals of expanded hypoxia, due to higher net burial rates of organic matter around the margins of the deep basins. Such intervals may be characterized by basin-scale acceleration of all fluxes within the P cycle, including productivity, regeneration and burial, sustained by the relative accessibility of the water column P pool beneath a shallow halocline.},
author = {Jilbert, T. and Slomp, C. P. and Gustafsson, B. G. and Boer, W.},
doi = {10.5194/bg-8-1699-2011},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Proposal papers/Measurement methods/Jilbert, Beyond the Fe-P-redox connection ( diffusive fluxes of Fe from pore water profiles).pdf:pdf},
isbn = {1726-4170},
issn = {17264170},
journal = {Biogeosciences},
number = {6},
pages = {1699--1720},
title = {{Beyond the Fe-P-redox connection: Preferential regeneration of phosphorus from organic matter as a key control on Baltic Sea nutrient cycles}},
volume = {8},
year = {2011}
}
@article{Palviainen2015,
abstract = {NO3, Mn, Fe, and SO4 act as terminal electron acceptors (TEAs), modifying mineralization pathways and coupling biogeochemical cycles. Although single TEA concentrations and fluxes have been intensively studied, the factors regulating the simultaneous fluxes and molar ratios of TEAs are poorly elucidated. We studied the mean concentrations, exports, and molar ratios of TEAs from 27 boreal catchments differing in land cover (percentage of agricultural land, peatland, forest, and built-up area) during the years 2000–2011. TEA exports and molar ratios were strongly controlled by land cover and only a little by atmospheric deposition. Fields produced the highest export of TEAs, particularly NO3. Peatland was linked to low NO3 and SO4, but high Fe exports. NO3, Mn, and Fe exports from forests were low, SO4 having proportionally the highest export. Together, the percentages of field and peatland predicted 93, 80, 75, and 67{\%} of the variation in the export of NO3, Mn, Fe, and SO4, respectively. The variable export of TEAs having different availability and physical behavior may create different premises for anaerobic mineralization in downstream systems, which adds a new dimension to the link between terrestrial system, land use, and environmental problems, such as eutrophication and climate change.},
author = {Palviainen, Marjo and Lehtoranta, Jouni and Ekholm, Petri and Ruoho-Airola, Tuija and Kortelainen, Pirkko},
doi = {10.1007/s10021-014-9832-y},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Ore estuary/Palviainen2015.pdf:pdf},
issn = {14350629},
journal = {Ecosystems},
keywords = {atmospheric deposition,climate change,eutrophication,iron,land cover,manganese,nitrate,organic carbon,sulfate},
number = {2},
pages = {343--358},
title = {{Land cover controls the export of terminal electron acceptors from boreal catchments}},
volume = {18},
year = {2015}
}
@misc{Solorzano1969,
author = {Solorzano, Lucia},
booktitle = {Limnology and Oceanography},
doi = {10.4319/lo.1969.14.5.0799},
issn = {19395590},
number = {5},
pages = {799--801},
title = {{Determination of ammonia in natural waters by the phenolhypochlorite method}},
volume = {14},
year = {1969}
}
@article{Poulton2002,
abstract = {Suspended sediments from 34 major rivers (geographically widespread)and 36 glacial meltwater streams have been examined for their variations in different operationally-defined iron fractions; FeHR (iron oxides soluble in dithionite), FePR (iron soluble in boiling HCl but not in dithionite) and FeU (total iron less that soluble in boiling HCl). River particulates show a close association between FeHR and total iron (FeT), reflecting the effects of chemical weathering which derive oxide iron$\backslash$r$\backslash$nfrom, and retain it in close association with, total iron. Consistent with this, continentalscale$\backslash$r$\backslash$naverage FeHR/FeT ratios vary with runoff ratios (average river runoff per unit$\backslash$r$\backslash$narea/average precipitation per unit area). By contrast, the diminished effects of$\backslash$r$\backslash$nchemical weathering produce no recognizable association of FeHR with FeT in glacial$\backslash$r$\backslash$nparticulates, and instead both FePR and FeU are closely correlated with FeT, reflecting$\backslash$r$\backslash$nessentially pristine mineralogy. A comparison of the globally-averaged compositions of$\backslash$r$\backslash$nriverine particulates and marine sediments reveals that the latter are depleted in FeHR,$\backslash$r$\backslash$nFePR and FeT but enriched in FeU. The river and glacial particulate data are combined$\backslash$r$\backslash$nwith estimates of authigenic, hydrothermal, atmospheric and coastal erosive iron$\backslash$r$\backslash$nfluxes from the literature to produce a global budget for FeHR, FePR, FeU and FeT.$\backslash$r$\backslash$nThis budget suggests that the differences between riverine particulates and marine$\backslash$r$\backslash$nsediments can be explained by; (i) preferentially removing FeHR from the riverine$\backslash$r$\backslash$nparticulate flux by deposition into inner shore reservoirs such as floodplains, salt$\backslash$r$\backslash$nmarshes and estuaries; and (ii) mixing the resulting riverine particulates with FeHRdepleted$\backslash$r$\backslash$nglacial particulates. Preliminary measurements of inner shore sediments are$\backslash$r$\backslash$nconsistent with (i) above. Phanerozoic and modern normal marine sediments have$\backslash$r$\backslash$nsimilar iron speciation characteristics, which implies the existence of a long-term$\backslash$r$\backslash$nsteady state for the iron cycle. This steady state could be maintained by a glacioeustatic$\backslash$r$\backslash$nfeedback, where FeHR-enriched riverine particulates are either more effectively trapped$\backslash$r$\backslash$nwhen sealevel is high (small ice masses, diminished glacial erosion), or are mixed with$\backslash$r$\backslash$ngreater masses of FeHR-depleted glacial particulates when sealevel is low (large ice$\backslash$r$\backslash$nmasses, enhanced glacial erosion). Further important controls on the steady state for FeHR operate through the formation of euxinic sediments and ironstones, which also$\backslash$r$\backslash$nprovide sealevel-dependent sinks for FeHR-enriched sediment.},
author = {Poulton, S. W. and Raiswell, R.},
doi = {10.2475/ajs.302.9.774},
isbn = {0002-9599},
issn = {00029599},
journal = {American Journal of Science},
number = {9},
pages = {774--805},
pmid = {8},
title = {{The low-temperature geochemical cycle of iron: From continental fluxes to marine sediment deposition}},
volume = {302},
year = {2002}
}
@article{Nixon1995,
abstract = {There is a need in the marine research and management communities for a clear operational definition of the term, eutrophication. I propose the following: eutrophication (noun) - an increase in the rate of supply of organic matter to an ecosystem. This definition is consistent with historical usage and emphasizes that eutrophication is a process, not a trophic state. A simple trophic classification for marine systems is also proposed: [GRAPHICS] Various factors may increase the supply of organic matter to coastal systems, but the most common is clearly nutrient enrichment. The major causes of nutrient enrichment in coastal areas are associated directly or indirectly with meeting the requirements and desires of human nutrition and diet. The deposition of reactive nitrogen emitted to the atmosphere as a consequence of fossil fuel combustion is also an important anthropogenic factor. The intensity of nitrogen emission from fertilizer, livestock waste, and fossil fuel combustion varies widely among the countries of the world. It is strongest in Europe, the northeastern United States, India/Pakistan, Japan/Korea, and the Caribbean. This geographical distribution corresponds with many areas where coastal marine eutrophication has become a recent concern. Demographic and social trends suggest that past practices leading to coastal nutrient enrichment are likely to be repeated in the coming decades in the developing countries of Asia, Africa, and Latin America.},
author = {Nixon, Scott W.},
doi = {10.1080/00785236.1995.10422044},
isbn = {0078-5326},
issn = {0078-5326},
journal = {Ophelia},
number = {September},
pages = {199--219},
title = {{Coastal marine eutrophication: a definition, social causes, and future concerns}},
url = {http://www.tandfonline.com/doi/abs/10.1080/00785236.1995.10422044{\%}5Cn{\%}3CGo to ISI{\%}3E://A1995QQ83600010},
volume = {41},
year = {1995}
}
@misc{Jørgensen1982b,
abstract = {The bacterial reduction of sulphate to sulphide at the sea bed is a key process in the oceanic sulphur cycle, and is responsible for the oxidation of organic matter which becomes buried below the oxic and sub-oxic zones of the sea bed. The oxic surface layer of the sea bed varies in thickness from a few millimetres in sheltered coastal areas to 1 m in pelagic sediments1,2. Below this layer, organic matter is mineralized mainly by fermenting, denitrifying, sulphate-reducing and methane-producing bacteria. Sulphate reduction is the predominant terminal step in the mineralization processes of sulphate-rich shelf sediments where the sulphate reducers inhibit the methanogens by competing with them for common substrates3−5. Sulphate reduction may therefore have a quantitatively important role in the overall oxidation of organic matter in the sea bed. Recently, concurrent measurements of oxygen uptake and sulphate reduction in a coastal sediment6 have demonstrated the importance of the sulphate-reducing bacteria in the mineralization of organic carbon. I present here the first comparative survey of aerobic and anaerobic mineralization in the sea bed based on direct rate measurements of the two processes. The results demonstrate a surprisingly high contribution from the sulphate-reducers. In coastal sediments, this specialized group of bacteria oxidized as much organic matter to CO2 as did all the aerobic organisms. Their relative contribution decreased three fold over the continental shelf from the shore to a depth of 200 m.},
author = {J{\o}rgensen, Bo Barker},
booktitle = {Nature},
doi = {10.1038/296643a0},
isbn = {0028-0836},
issn = {0028-0836},
keywords = {MARINE SEDIMENT,radiotracer,sulfate reduction},
number = {5858},
pages = {643--645},
pmid = {26679},
title = {{Mineralization of organic matter in the sea bed – the role of sulphate reduction}},
url = {http://dx.doi.org/10.1038/296643a0},
volume = {296},
year = {1982}
}
@article{Segarra2013,
abstract = {Methane, a powerful greenhouse gas, is both produced and consumed in anoxic coastal sediments via microbial processes. Although the anaerobic oxidation of methane (AOM) is almost certainly an important process in coastal freshwater and salt marsh sediments, the factors that control the rates and pathways of AOM in these habitats are poorly understood. Here, we present the first direct measurements of AOM activity in freshwater (0. PSU) and brackish (25. PSU) wetland sediments. Despite disparate sulfate concentrations, both environments supported substantial rates of AOM. Higher sulfate reduction (SR) rates were measured in the freshwater site and SR at both sites was of sufficient magnitude to support the observed AOM activity. Laboratory incubations of freshwater and brackish tidal, wetland sediments amended with either nothing [control], sulfate, nitrate, manganese oxide (birnessite) or iron oxide (ferrihydrite) and supplied with a methane headspace were used to evaluate the impact(s) of electron acceptor availability on potential AOM rates. Maximum AOM rates in brackish slurries occurred in the sulfate amendments. In contrast, addition of sulfate and several possible electron acceptors to the freshwater slurries decreased AOM rates relative to the control. High ratios of AOM activity relative to SR activity in the nitrate, birnessite, and ferrihydrite treatments of both the brackish and freshwater slurries provided evidence of AOM decoupled from SR. This study demonstrates that both freshwater and brackish coastal wetland sediments support considerable rates of anaerobic methanotrophy and provides evidence for sulfate-independent AOM that may be coupled to nitrate, iron, or manganese reduction in both environments. ?? 2013 Elsevier Ltd.},
author = {Segarra, Katherine E a and Comerford, Christopher and Slaughter, Julia and Joye, Samantha B.},
doi = {10.1016/j.gca.2013.03.029},
file = {:C$\backslash$:/Users/Wytse Lenstra/SURFdrive/PhD/Papers/Proposal papers/Katherine, Impact of electron acceptor availability on the anaerobic oxidation of methane (Fe and Methane).pdf:pdf},
isbn = {0016-7037},
issn = {00167037},
journal = {Geochimica et Cosmochimica Acta},
pages = {15--30},
publisher = {Elsevier Ltd},
title = {{Impact of electron acceptor availability on the anaerobic oxidation of methane in coastal freshwater and brackish wetland sediments}},
url = {http://dx.doi.org/10.1016/j.gca.2013.03.029},
volume = {115},
year = {2013}
}
