Articles | Volume 10, issue 8
https://doi.org/10.5194/bg-10-5533-2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/bg-10-5533-2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
16 Aug 2013
Research article |
| 16 Aug 2013
Seasonal changes in photochemical properties of dissolved organic matter in small boreal streams
P. Porcal
Environmental and Resource Studies, Trent University, 1600 West Bank Drive, Peterborough, ON, K9J 7B8, Canada
Biology Centre of the AS CR, v.v.i., Institute of Hydrobiology, České Budějovice, Czech Republic
P. J. Dillon
Environmental and Resource Studies, Trent University, 1600 West Bank Drive, Peterborough, ON, K9J 7B8, Canada
L. A. Molot
Faculty of Environmental Studies, York University, 4700 Keele Street, Toronto, ON, M3J 1P3, Canada
Related authors
Nana O.-A. Osafo, Jiří Jan, Petr Porcal, Daniel A. Petrash, and Jakub Borovec
Biogeosciences Discuss., https://doi.org/10.5194/bg-2020-296, https://doi.org/10.5194/bg-2020-296, 2020
Manuscript not accepted for further review
Short summary
Short summary
We investigated the role that OM quality plays in the stability of the OM-Fe association in freshwater sediments. It was found that non-humic components enhance OM-Fe stability, while humic components enhance the reductive dissolution of OM-Fe. This information is useful for predicting the fate of OM-Fe in freshwater systems with discrete sources of OM. Stable OM-Fe complexes improve aqueous environments by reducing the release of greenhouse gases, heavy metals and excess nutrients, such as P.
Nana O.-A. Osafo, Jiří Jan, Petr Porcal, Daniel A. Petrash, and Jakub Borovec
Biogeosciences Discuss., https://doi.org/10.5194/bg-2020-296, https://doi.org/10.5194/bg-2020-296, 2020
Manuscript not accepted for further review
Short summary
Short summary
We investigated the role that OM quality plays in the stability of the OM-Fe association in freshwater sediments. It was found that non-humic components enhance OM-Fe stability, while humic components enhance the reductive dissolution of OM-Fe. This information is useful for predicting the fate of OM-Fe in freshwater systems with discrete sources of OM. Stable OM-Fe complexes improve aqueous environments by reducing the release of greenhouse gases, heavy metals and excess nutrients, such as P.
J. Crossman, M. N. Futter, P. G. Whitehead, E. Stainsby, H. M. Baulch, L. Jin, S. K. Oni, R. L. Wilby, and P. J. Dillon
Hydrol. Earth Syst. Sci., 18, 5125–5148, https://doi.org/10.5194/hess-18-5125-2014, https://doi.org/10.5194/hess-18-5125-2014, 2014
Short summary
Short summary
We projected potential hydrochemical responses in four neighbouring catchments to a range of future climates. The highly variable responses in streamflow and total phosphorus (TP) were governed by geology and flow pathways, where larger catchment responses were proportional to greater soil clay content. This suggests clay content might be used as an indicator of catchment sensitivity to climate change, and highlights the need for catchment-specific management plans.
Related subject area
Biogeochemistry: Limnology
Tracing rate and extent of human induced hypoxia during the last 200 years in the mesotrophic lake Tiefer See (NE Germany)
Thermal stratification and meromixis in four dilute temperate zone lakes
Mercury records covering the past 90 000 years from lakes Prespa and Ohrid, SE Europe
Temporary stratification promotes large greenhouse gas emissions in a shallow eutrophic lake
The influence of carbon cycling on oxygen depletion in north-temperate lakes
Conceptual models of dissolved carbon fluxes in a two-layer stratified lake: interannual typhoon responses under extreme climates
Soil-biodegradable plastic films do not decompose in a lake sediment over 9 months of incubation
Anthropogenic activities significantly increase annual greenhouse gas (GHG) fluxes from temperate headwater streams in Germany
Role of formation and decay of seston organic matter in the fate of methylmercury within the water column of a eutrophic lake
Contrasting activation energies of litter-associated respiration and P uptake drive lower cumulative P uptake at higher temperatures
Rapidly increasing sulfate concentration: a hidden promoter of eutrophication in shallow lakes
The dominant role of sunlight in degrading winter dissolved organic matter from a thermokarst lake in a subarctic peatland
Dissolved organic matter signatures in urban surface waters: spatio-temporal patterns and drivers
Towards a history of Holocene P dynamics for the Northern Hemisphere using lake sediment geochemical records
Methane in the Danube Delta: the importance of spatial patterns and diel cycles for atmospheric emission estimates
Methane oxidation in the waters of a humic-rich boreal lake stimulated by photosynthesis, nitrite, Fe(III) and humics
Porewater δ13CDOC indicates variable extent of degradation in different talik layers of coastal Alaskan thermokarst lakes
Holocene phototrophic community and anoxia dynamics in meromictic Lake Jaczno (NE Poland) using high-resolution hyperspectral imaging and HPLC data
Changing sources and processes sustaining surface CO2 and CH4 fluxes along a tropical river to reservoir system
The relative importance of photodegradation and biodegradation of terrestrially derived dissolved organic carbon across four lakes of differing trophic status
The influences of historic lake trophy and mixing regime changes on long-term phosphorus fraction retention in sediments of deep eutrophic lakes: a case study from Lake Burgäschi, Switzerland
Ice formation on lake surfaces in winter causes warm-season bias of lacustrine brGDGT temperature estimates
Drivers of diffusive CH4 emissions from shallow subarctic lakes on daily to multi-year timescales
High organic carbon burial but high potential for methane ebullition in the sediments of an Amazonian hydroelectric reservoir
Direct O2 control on the partitioning between denitrification and dissimilatory nitrate reduction to ammonium in lake sediments
Spatial distribution of environmental indicators in surface sediments of Lake Bolshoe Toko, Yakutia, Russia
Ostracods as ecological and isotopic indicators of lake water salinity changes: the Lake Van example
Reviews and syntheses: Dams, water quality and tropical reservoir stratification
Nitrogen cycling in Sandusky Bay, Lake Erie: oscillations between strong and weak export and implications for harmful algal blooms
Distinctive effects of allochthonous and autochthonous organic matter on CDOM spectra in a tropical lake
High-frequency productivity estimates for a lake from free-water CO2 concentration measurements
Nitrification and ammonium dynamics in Taihu Lake, China: seasonal competition for ammonium between nitrifiers and cyanobacteria
Quality transformation of dissolved organic carbon during water transit through lakes: contrasting controls by photochemical and biological processes
Continuous measurement of air–water gas exchange by underwater eddy covariance
Capturing temporal and spatial variability in the chemistry of shallow permafrost ponds
Organic carbon mass accumulation rate regulates the flux of reduced substances from the sediments of deep lakes
Cyanobacterial carbon concentrating mechanisms facilitate sustained CO2 depletion in eutrophic lakes
New insights on resource stoichiometry: assessing availability of carbon, nitrogen, and phosphorus to bacterioplankton
Spatio-seasonal variability of chromophoric dissolved organic matter absorption and responses to photobleaching in a large shallow temperate lake
Isotopic composition of nitrate and particulate organic matter in a pristine dam reservoir of western India: implications for biogeochemical processes
Bacterial production in subarctic peatland lakes enriched by thawing permafrost
Photochemical mineralisation in a boreal brown water lake: considerable temporal variability and minor contribution to carbon dioxide production
Are flood-driven turbidity currents hot spots for priming effect in lakes?
Organic carbon burial efficiency in a subtropical hydroelectric reservoir
Importance of within-lake processes in affecting the dynamics of dissolved organic carbon and dissolved organic and inorganic nitrogen in an Adirondack forested lake/watershed
Temperature dependence of the relationship between pCO2 and dissolved organic carbon in lakes
The nature of organic carbon in density-fractionated sediments in the Sacramento-San Joaquin River Delta (California)
Microbial nutrient limitation in Arctic lakes in a permafrost landscape of southwest Greenland
Phototrophic pigment diversity and picophytoplankton in permafrost thaw lakes
Carbon dynamics in highly heterotrophic subarctic thaw ponds
Ido Sirota, Rik Tjallingii, Sylvia Pinkerneil, Birgit Schroeder, Marlen Albert, Rebecca Kearney, Oliver Heiri, Simona Breu, and Achim Brauer
EGUsphere, https://doi.org/10.5194/egusphere-2024-835, https://doi.org/10.5194/egusphere-2024-835, 2024
Short summary
Short summary
Hypoxia has spread in lake Tiefer-See (NE Germany) due to the increased human activity. The onset of hypoxia indicated by varve preservation is dated to ~1920 at the lake’s depocenter, which respond faster and more severely to the reduction in oxygen level. The spread of hypoxic conditions is a gradual process that lasted for nearly one hundred years, and the chemistry of the sediments shows that the depletion in oxygen in the lake started several decades before the onset of varve preservation.
Elizabeth D. Swanner, Chris Harding, Sajjad A. Akam, Ioan Lascu, Gabrielle Ledesma, Pratik Poudel, Heeyeon Sun, Samuel Duncanson, Karly Bandy, Alex Branham, Liza Bryant-Tapper, Tanner Conwell, Omri Jamison, and Lauren Netz
Biogeosciences, 21, 1549–1562, https://doi.org/10.5194/bg-21-1549-2024, https://doi.org/10.5194/bg-21-1549-2024, 2024
Short summary
Short summary
Four lakes were thought to be permanently stratified. Years’ worth of data indicate only one lake is permanently stratified. Strong temperature gradients keep it stratified – unusual for a lake in a temperate climate. The lake has elevated oxygen concentrations within the temperature gradient. Rapid development of the gradient in the spring traps oxygen, and oxygen production by photosynthetic organisms during the summer adds more.
Alice R. Paine, Isabel M. Fendley, Joost Frieling, Tamsin A. Mather, Jack H. Lacey, Bernd Wagner, Stuart A. Robinson, David M. Pyle, Alexander Francke, Theodore R. Them II, and Konstantinos Panagiotopoulos
Biogeosciences, 21, 531–556, https://doi.org/10.5194/bg-21-531-2024, https://doi.org/10.5194/bg-21-531-2024, 2024
Short summary
Short summary
Many important processes within the global mercury (Hg) cycle operate over thousands of years. Here, we explore the timing, magnitude, and expression of Hg signals retained in sediments of lakes Prespa and Ohrid over the past ∼90 000 years. Divergent signals suggest that local differences in sediment composition, lake structure, and water balance influence the local Hg cycle and determine the extent to which sedimentary Hg signals reflect local- or global-scale environmental changes.
Thomas A. Davidson, Martin Søndergaard, Joachim Audet, Eti Levi, Chiara Esposito, Tuba Bucak, and Anders Nielsen
Biogeosciences, 21, 93–107, https://doi.org/10.5194/bg-21-93-2024, https://doi.org/10.5194/bg-21-93-2024, 2024
Short summary
Short summary
Shallow lakes and ponds undergo frequent stratification in summer months. Here we studied how this affects greenhouse gas (GHG) emissions. We found that stratification caused anoxia in the bottom waters, driving increased GHG emissions, in particular methane released as bubbles. In addition, methane and carbon dioxide accumulated in the bottom waters during stratification, leading to large emissions when the lake mixed again.
Austin Delany, Robert Ladwig, Cal Buelo, Ellen Albright, and Paul C. Hanson
Biogeosciences, 20, 5211–5228, https://doi.org/10.5194/bg-20-5211-2023, https://doi.org/10.5194/bg-20-5211-2023, 2023
Short summary
Short summary
Internal and external sources of organic carbon (OC) in lakes can contribute to oxygen depletion, but their relative contributions remain in question. To study this, we built a two-layer model to recreate processes relevant to carbon for six Wisconsin lakes. We found that internal OC was more important than external OC in depleting oxygen. This shows that it is important to consider both the fast-paced cycling of internally produced OC and the slower cycling of external OC when studying lakes.
Hao-Chi Lin, Keisuke Nakayama, Jeng-Wei Tsai, and Chih-Yu Chiu
Biogeosciences, 20, 4359–4376, https://doi.org/10.5194/bg-20-4359-2023, https://doi.org/10.5194/bg-20-4359-2023, 2023
Short summary
Short summary
We successfully developed conceptual models to examine how dissolved carbon distributions change with climate within a small subtropical lake, considering both physical and biochemical processes. Typhoons controlled the seasonal and interannual variation in C fluxes due to large amounts of carbon loading and rapid mixing within the whole lake, resulting in the net primary production being 3.14 times higher in typhoon years than in non-typhoon years in Yuan‒Yang Lake.
Sigrid van Grinsven and Carsten Schubert
Biogeosciences, 20, 4213–4220, https://doi.org/10.5194/bg-20-4213-2023, https://doi.org/10.5194/bg-20-4213-2023, 2023
Short summary
Short summary
Agriculture relies heavily on plastic mulch films, which may be transported to aquatic environments. We investigated the breakdown of soil-biodegradable agricultural mulch films in lake sediments. After 40 weeks, films were intact, and no significant CO2 or CH4 was produced from the biodegradable mulch films. We conclude that the mulch films we used have a low biodegradability in lake sediments. The sediment lacks the microbes needed to break down the biodegradable plastics that were used here.
Ricky Mwangada Mwanake, Gretchen Maria Gettel, Elizabeth Gachibu Wangari, Clarissa Glaser, Tobias Houska, Lutz Breuer, Klaus Butterbach-Bahl, and Ralf Kiese
Biogeosciences, 20, 3395–3422, https://doi.org/10.5194/bg-20-3395-2023, https://doi.org/10.5194/bg-20-3395-2023, 2023
Short summary
Short summary
Despite occupying <1 %; of the globe, streams are significant sources of greenhouse gas (GHG) emissions. In this study, we determined anthropogenic effects on GHG emissions from streams. We found that anthropogenic-influenced streams had up to 20 times more annual GHG emissions than natural ones and were also responsible for seasonal peaks. Anthropogenic influences also altered declining GHG flux trends with stream size, with potential impacts on stream-size-based spatial upscaling techniques.
Laura Balzer, Carluvy Baptista-Salazar, Sofi Jonsson, and Harald Biester
Biogeosciences, 20, 1459–1472, https://doi.org/10.5194/bg-20-1459-2023, https://doi.org/10.5194/bg-20-1459-2023, 2023
Short summary
Short summary
Toxic methylmercury (MeHg) in lakes can be enriched in fish and is harmful for humans. Phytoplankton is the entry point for MeHg into the aquatic food chain. We investigated seasonal MeHg concentrations in plankton of a productive lake. Our results show that high amounts of MeHg occur in algae and suspended matter in lakes and that productive lakes are hot spots of MeHg formation, which is mainly controlled by decomposition of algae organic matter and water-phase redox conditions.
Nathan J. Tomczyk, Amy D. Rosemond, Anna Kaz, and Jonathan P. Benstead
Biogeosciences, 20, 191–204, https://doi.org/10.5194/bg-20-191-2023, https://doi.org/10.5194/bg-20-191-2023, 2023
Short summary
Short summary
Warming is expected to increase rates of microbial metabolism, but the effect of warming on nutrient demand is unclear. Our experiments demonstrate that microbial nutrient uptake increases less with temperature than metabolism, particularly when environmental nutrient concentrations are low. However, our simulation models suggest that warming may actually lead to declines in ecosystem-scale nutrient uptake as warming accelerates the depletion of carbon substrates required for microbial growth.
Chuanqiao Zhou, Yu Peng, Li Chen, Miaotong Yu, Muchun Zhou, Runze Xu, Lanqing Zhang, Siyuan Zhang, Xiaoguang Xu, Limin Zhang, and Guoxiang Wang
Biogeosciences, 19, 4351–4360, https://doi.org/10.5194/bg-19-4351-2022, https://doi.org/10.5194/bg-19-4351-2022, 2022
Short summary
Short summary
The dramatical increase in SO42- concentration up to 100 mg L-1 in eutrophic lakes has aroused great attention. It enhanced the sulfate reduction to release a large amount of ΣS2- during cyanobacteria decomposition. The Fe2+ released from the iron reduction process is captured by ΣS2-, and finally the combination of iron and P was reduced, promoting the release of endogenous P. Therefore, increasing sulfate concentrations are shown to be a hidden promoter of eutrophication in shallow lakes.
Flora Mazoyer, Isabelle Laurion, and Milla Rautio
Biogeosciences, 19, 3959–3977, https://doi.org/10.5194/bg-19-3959-2022, https://doi.org/10.5194/bg-19-3959-2022, 2022
Short summary
Short summary
Dissolved organic matter collected at the end of winter from a peatland thermokarst lake was highly transformed and degraded by sunlight, leading to bacterial stimulation and CO2 production, but a fraction was also potentially lost by photoflocculation. Over 18 days, 18 % of the incubated dissolved organic matter was lost under sunlight, while dark bacterial degradation was negligible. Sunlight could have a marked effect on carbon cycling in organic-rich thermokarst lakes after ice-off.
Clara Romero González-Quijano, Sonia Herrero Ortega, Peter Casper, Mark O. Gessner, and Gabriel A. Singer
Biogeosciences, 19, 2841–2853, https://doi.org/10.5194/bg-19-2841-2022, https://doi.org/10.5194/bg-19-2841-2022, 2022
Short summary
Short summary
Despite today's diversity of methods to measure dissolved organic matter (DOM), its potential to give ecological information about urban surface waters has been underused. We found DOM from urban lakes and ponds to differ greatly from that of urban streams and rivers in composition as well as temporal turnover. Urban land use (the percentage of green space), nutrient supply and point source pollution were the principal drivers of DOM. We suggest including DOM composition in regular monitoring.
Madeleine Moyle, John F. Boyle, and Richard C. Chiverrell
Biogeosciences, 18, 5609–5638, https://doi.org/10.5194/bg-18-5609-2021, https://doi.org/10.5194/bg-18-5609-2021, 2021
Short summary
Short summary
We reconstruct Holocene landscape P yield and lake water TP concentration for 24 sites across the Northern Hemisphere by applying a process model to published lake sediment geochemical records. We find sites with the same landscape development history show similar geochemical profiles depending on climate, human impact, and other local factors. Our reconstructions can be used to understand present-day terrestrial P cycling, lake water nutrient status, and export of terrestrial P to the oceans.
Anna Canning, Bernhard Wehrli, and Arne Körtzinger
Biogeosciences, 18, 3961–3979, https://doi.org/10.5194/bg-18-3961-2021, https://doi.org/10.5194/bg-18-3961-2021, 2021
Short summary
Short summary
Inland waters are usually not well restrained in terms of greenhouse gas measurements. One of these regions is the Danube Delta, Romania. Therefore, we measured continuously with sensors to collect high-resolution data for CH4 and O2 throughout the Delta. We found significant variation for all concentrations over the day and night and between regions, as well as large spatial variation throughout all regions, with large CH4 concentrations flowing in from the reed beds to the lakes.
Sigrid van Grinsven, Kirsten Oswald, Bernhard Wehrli, Corinne Jegge, Jakob Zopfi, Moritz F. Lehmann, and Carsten J. Schubert
Biogeosciences, 18, 3087–3101, https://doi.org/10.5194/bg-18-3087-2021, https://doi.org/10.5194/bg-18-3087-2021, 2021
Short summary
Short summary
Lake Lovojärvi is a nutrient-rich lake with high amounts of methane at the bottom, but little near the top. Methane comes from the sediment and rises up through the water but is consumed by microorganisms along the way. They use oxygen if available, but in deeper water layers, no oxygen was present. There, nitrite, iron and humic substances were used, besides a collaboration between photosynthetic organisms and methane consumers, in which the first produced oxygen for the latter.
Ove H. Meisel, Joshua F. Dean, Jorien E. Vonk, Lukas Wacker, Gert-Jan Reichart, and Han Dolman
Biogeosciences, 18, 2241–2258, https://doi.org/10.5194/bg-18-2241-2021, https://doi.org/10.5194/bg-18-2241-2021, 2021
Short summary
Short summary
Arctic permafrost lakes form thaw bulbs of unfrozen soil (taliks) beneath them where carbon degradation and greenhouse gas production are increased. We analyzed the stable carbon isotopes of Alaskan talik sediments and their porewater dissolved organic carbon and found that the top layers of these taliks are likely more actively degraded than the deeper layers. This in turn implies that these top layers are likely also more potent greenhouse gas producers than the underlying deeper layers.
Stamatina Makri, Andrea Lami, Luyao Tu, Wojciech Tylmann, Hendrik Vogel, and Martin Grosjean
Biogeosciences, 18, 1839–1856, https://doi.org/10.5194/bg-18-1839-2021, https://doi.org/10.5194/bg-18-1839-2021, 2021
Short summary
Short summary
Anoxia in lakes is a major growing concern. In this study we applied a multiproxy approach combining high-resolution hyperspectral imaging (HSI) pigment data with specific HPLC data to examine the Holocene evolution and main drivers of lake anoxia and trophic state changes. We find that when human impact was low, these changes were driven by climate and natural lake-catchment evolution. In the last 500 years, increasing human impact has promoted lake eutrophication and permanent anoxia.
Cynthia Soued and Yves T. Prairie
Biogeosciences, 18, 1333–1350, https://doi.org/10.5194/bg-18-1333-2021, https://doi.org/10.5194/bg-18-1333-2021, 2021
Short summary
Short summary
Freshwater reservoirs emit greenhouse gases (GHGs, CO2 and CH4) to the atmosphere; however, the sources underlying these emissions are numerous, and their magnitude is not well known. This study quantifies surface CO2 and CH4 emissions and all their potential sources in a tropical reservoir. Results highlight the changes in GHG sources along the river–reservoir continuum, with internal metabolism being a key component but highly uncertain and challenging to estimate at an ecosystem scale.
Christopher M. Dempsey, Jennifer A. Brentrup, Sarah Magyan, Lesley B. Knoll, Hilary M. Swain, Evelyn E. Gaiser, Donald P. Morris, Michael T. Ganger, and Craig E. Williamson
Biogeosciences, 17, 6327–6340, https://doi.org/10.5194/bg-17-6327-2020, https://doi.org/10.5194/bg-17-6327-2020, 2020
Short summary
Short summary
We looked at how terrestrial dissolved organic carbon (DOC) from the watersheds of four different lakes responded to both biodegradation (i.e., microbes) and photodegradation (i.e., sunlight). The traditional paradigm is that biodegradation is more important than photodegradation. Our research shows that, on short timescales (i.e., 7 d), sunlight is more important than microbes in degrading DOC. Interestingly, the lakes had different responses to sunlight based on their trophic status.
Luyao Tu, Paul Zander, Sönke Szidat, Ronald Lloren, and Martin Grosjean
Biogeosciences, 17, 2715–2729, https://doi.org/10.5194/bg-17-2715-2020, https://doi.org/10.5194/bg-17-2715-2020, 2020
Short summary
Short summary
In a small, deep lake on the Swiss Plateau, net fluxes of labile P fractions in sediments that can be released to surface waters have been predominately controlled by past hypolimnetic anoxic conditions since the early 1900s. More than 40 years of hypolimnetic withdrawal can effectively reduce net P fluxes in sediments and internal P loads but not effectively decrease eutrophication. These findings should likely serve the management of deep eutrophic lakes in temperate zones.
Jiantao Cao, Zhiguo Rao, Fuxi Shi, and Guodong Jia
Biogeosciences, 17, 2521–2536, https://doi.org/10.5194/bg-17-2521-2020, https://doi.org/10.5194/bg-17-2521-2020, 2020
Short summary
Short summary
BrGDGT distribution in Gonghai Lake is different from surrounding soils, and its derived temperature reflects a mean annual lake water temperature (LWT) that is higher than the mean annual air temperature (AT). The higher mean annual LWT is due to ice formation in winter that prevents thermal exchange between lake water and air.
Joachim Jansen, Brett F. Thornton, Alicia Cortés, Jo Snöälv, Martin Wik, Sally MacIntyre, and Patrick M. Crill
Biogeosciences, 17, 1911–1932, https://doi.org/10.5194/bg-17-1911-2020, https://doi.org/10.5194/bg-17-1911-2020, 2020
Short summary
Short summary
Lakes are important emitters of the greenhouse gas methane. We use field observations and a model to evaluate the importance of known drivers of methane production and release. Fast and slow changes of the diffusive flux were governed by wind speed and sediment temperature, respectively. Increased turbulence enhanced release, but storms depleted the lakes of gas and limited emissions. Our findings may inform model studies on the effects of weather and climate change on lake methane emissions.
Gabrielle R. Quadra, Sebastian Sobek, José R. Paranaíba, Anastasija Isidorova, Fábio Roland, Roseilson do Vale, and Raquel Mendonça
Biogeosciences, 17, 1495–1505, https://doi.org/10.5194/bg-17-1495-2020, https://doi.org/10.5194/bg-17-1495-2020, 2020
Short summary
Short summary
Hydropower is expanding in the Amazon Basin, but the potential effects of river damming on carbon fluxes cannot be gauged due to a lack of studies. We quantified, for the first time in an Amazonian reservoir, both organic carbon burial and the concentrations of methane in the sediments. We found that the dual role of sediments as both a carbon sink and methane source may be particularly pronounced in this Amazonian reservoir.
Adeline N. Y. Cojean, Jakob Zopfi, Alan Gerster, Claudia Frey, Fabio Lepori, and Moritz F. Lehmann
Biogeosciences, 16, 4705–4718, https://doi.org/10.5194/bg-16-4705-2019, https://doi.org/10.5194/bg-16-4705-2019, 2019
Short summary
Short summary
Our results demonstrate the importance of oxygen in regulating the fate of nitrogen (N) in the sediments of Lake Lugano south basin, Switzerland. Hence, our study suggests that, by changing oxygen concentration in bottom waters, the seasonal water column turnover may significantly regulate the partitioning between N removal and N recycling in surface sediments, and it is likely that a similar pattern can be expected in a wide range of environments.
Boris K. Biskaborn, Larisa Nazarova, Lyudmila A. Pestryakova, Liudmila Syrykh, Kim Funck, Hanno Meyer, Bernhard Chapligin, Stuart Vyse, Ruslan Gorodnichev, Evgenii Zakharov, Rong Wang, Georg Schwamborn, Hannah L. Bailey, and Bernhard Diekmann
Biogeosciences, 16, 4023–4049, https://doi.org/10.5194/bg-16-4023-2019, https://doi.org/10.5194/bg-16-4023-2019, 2019
Short summary
Short summary
To better understand time-series data in lake sediment cores in times of rapidly changing climate, we study within-lake spatial variabilities of environmental indicator data in 38 sediment surface samples along spatial habitat gradients in the boreal deep Lake Bolshoe Toko (Russia). Our methods comprise physicochemical as well as diatom and chironomid analyses. Species diversities vary according to benthic niches, while abiotic proxies depend on river input, water depth, and catchment lithology.
Jeremy McCormack, Finn Viehberg, Derya Akdemir, Adrian Immenhauser, and Ola Kwiecien
Biogeosciences, 16, 2095–2114, https://doi.org/10.5194/bg-16-2095-2019, https://doi.org/10.5194/bg-16-2095-2019, 2019
Short summary
Short summary
We juxtapose changes in ostracod taxonomy, morphology (noding) and oxygen (δ18O) and carbon (δ13C) isotopic composition for the last 150 kyr with independent low-resolution salinity proxies. We demonstrate that for Lake Van, salinity is the most important factor influencing the composition of the ostracod assemblage and the formation of nodes on the valves of limnocytherinae species. Ostracod δ18O shows a higher sensibility towards climatic and hydrological variations than the bulk isotopy.
Robert Scott Winton, Elisa Calamita, and Bernhard Wehrli
Biogeosciences, 16, 1657–1671, https://doi.org/10.5194/bg-16-1657-2019, https://doi.org/10.5194/bg-16-1657-2019, 2019
Short summary
Short summary
A global boom in dam construction throughout the world’s tropics motivated us to review and synthesize information on the water quality impacts of dams with a focus on low-latitude contexts and scope for mitigation. Sediment trapping and reservoir stratification are key process driving chemical and ecological impacts on tropical rivers. We analyze the 54 most-voluminous low-latitude reservoirs and find that stratification seems to be a ubiquitous phenomenon.
Kateri R. Salk, George S. Bullerjahn, Robert Michael L. McKay, Justin D. Chaffin, and Nathaniel E. Ostrom
Biogeosciences, 15, 2891–2907, https://doi.org/10.5194/bg-15-2891-2018, https://doi.org/10.5194/bg-15-2891-2018, 2018
Short summary
Short summary
This paper highlights dynamic nitrogen cycling in a freshwater estuary, with implications for harmful algal blooms and downstream nitrogen loading. Phytoplankton and microbes actively consumed nitrogen in this system, contributing to recycling of nitrogen within the system and permanent nitrogen removal, respectively. However, delivery of nitrogen from the river and fixation of atmospheric nitrogen by phytoplankton outweighed nitrogen uptake, resulting in variable downstream nitrogen delivery.
Luciana Pena Mello Brandão, Ludmila Silva Brighenti, Peter Anton Staehr, Eero Asmala, Philippe Massicotte, Denise Tonetta, Francisco Antônio Rodrigues Barbosa, Diego Pujoni, and José Fernandes Bezerra-Neto
Biogeosciences, 15, 2931–2943, https://doi.org/10.5194/bg-15-2931-2018, https://doi.org/10.5194/bg-15-2931-2018, 2018
Short summary
Short summary
Using mesocosms we investigated the effect of the increase in the allochthonous and autochthonous sources of DOM in a tropical lake, in order to simulate its effects on the characteristics of lakes caused by anthropogenic impacts. The seasonal allochthonous input has much larger effects on the lake and, in addition to increasing nutrients, alters the transparency of water and consequently controls the seasonal dynamics of phytoplankton (autochthonous source) and lake ecology.
Maria Provenzale, Anne Ojala, Jouni Heiskanen, Kukka-Maaria Erkkilä, Ivan Mammarella, Pertti Hari, and Timo Vesala
Biogeosciences, 15, 2021–2032, https://doi.org/10.5194/bg-15-2021-2018, https://doi.org/10.5194/bg-15-2021-2018, 2018
Short summary
Short summary
We extensively tested and refined a direct, high-frequency free-water CO2 measurement method to study the lake net ecosystem productivity. The method was first proposed in 2008, but neglected ever since.
With high-frequency direct methods, we can calculate the lake productivity more precisely, and parameterise its dependency on environmental variables. This helps us expand our knowledge on the carbon cycle in the water, and leads to a better integration of water bodies in carbon budgets.
Justyna J. Hampel, Mark J. McCarthy, Wayne S. Gardner, Lu Zhang, Hai Xu, Guangwei Zhu, and Silvia E. Newell
Biogeosciences, 15, 733–748, https://doi.org/10.5194/bg-15-733-2018, https://doi.org/10.5194/bg-15-733-2018, 2018
Short summary
Short summary
Our paper highlights the importance of dual-nutrient management: nitrogen (N) and phosphorus (P) in lakes with cyanobacterial harmful algal blooms.
Taihu Lake (China) experiences seasonal blooms due to increased input of N and P from field runoff. The main process investigated in our study, nitrification,
is important for N removal through denitrification. We show that nitrification is less efficient during the blooms, due to competition for nutrients between
N microbes and cyanobacteria.
Martin Berggren, Marcus Klaus, Balathandayuthabani Panneer Selvam, Lena Ström, Hjalmar Laudon, Mats Jansson, and Jan Karlsson
Biogeosciences, 15, 457–470, https://doi.org/10.5194/bg-15-457-2018, https://doi.org/10.5194/bg-15-457-2018, 2018
Short summary
Short summary
The quality of dissolved organic carbon (DOC), especially its color, is a defining feature of freshwater ecosystems. We found that colored DOC fractions are surprisingly resistant to natural degradation during water transit through many brown-water lakes. This is explained by the dominance of microbial processes that appear to selectively remove noncolored DOC. However, in lakes where sunlight degradation plays a relatively larger role, significant DOC bleaching occurs.
Peter Berg and Michael L. Pace
Biogeosciences, 14, 5595–5606, https://doi.org/10.5194/bg-14-5595-2017, https://doi.org/10.5194/bg-14-5595-2017, 2017
Short summary
Short summary
We use the aquatic eddy covariance technique – developed first for benthic O2 flux measurements – right below the air–water interface (~ 4 cm) to determine gas exchange rates and coefficients. This use of the technique is particularly useful in studies of gas exchange and its dynamics and controls. The approach can thus help reduce the recognized problem of large uncertainties linked to gas exchange estimates in traditional aquatic ecosystem studies.
Matthew Q. Morison, Merrin L. Macrae, Richard M. Petrone, and LeeAnn Fishback
Biogeosciences, 14, 5471–5485, https://doi.org/10.5194/bg-14-5471-2017, https://doi.org/10.5194/bg-14-5471-2017, 2017
Short summary
Short summary
Shallow ponds and lakes are common features in permafrost systems. We show that the chemistry of these water bodies can be dynamic, although the changes are consistent through time between ponds. This synchrony in some water chemistry appears to be related to water level variations. Because hydrological conditions can vary greatly over the course of the year and during a storm, this work underscores the importance of interpreting water samples from these systems within their hydrologic context.
Thomas Steinsberger, Martin Schmid, Alfred Wüest, Robert Schwefel, Bernhard Wehrli, and Beat Müller
Biogeosciences, 14, 3275–3285, https://doi.org/10.5194/bg-14-3275-2017, https://doi.org/10.5194/bg-14-3275-2017, 2017
Short summary
Short summary
Based on a broad dataset of lake sediment analysis and porewater measurements from various Swiss lakes, this paper argues that the accumulation of organic carbon in the sediment is one of the main driving forces for the generation of reduced substances such as methane and ammonia. These substances significantly contribute to the hypolimnetic oxygen consumption. The relationships presented help to evaluate the scale of the flux of reduced substances where no direct measurements are available.
Ana M. Morales-Williams, Alan D. Wanamaker Jr., and John A. Downing
Biogeosciences, 14, 2865–2875, https://doi.org/10.5194/bg-14-2865-2017, https://doi.org/10.5194/bg-14-2865-2017, 2017
Short summary
Short summary
Our study investigated the mechanisms sustaining cyanobacteria blooms when CO2 is depleted in lake surface waters. We found that when lake CO2 concentrations drop below those of the atmosphere, cyanobacteria switch on carbon concentrating mechanisms (CCMs), allowing them to actively take up bicarbonate. This may provide bloom-forming cyanobacteria with a competitive advantage over other algae. These results provide insight into the timing and duration of blooms in high-nutrient lakes.
Ana R. A. Soares, Ann-Kristin Bergström, Ryan A. Sponseller, Joanna M. Moberg, Reiner Giesler, Emma S. Kritzberg, Mats Jansson, and Martin Berggren
Biogeosciences, 14, 1527–1539, https://doi.org/10.5194/bg-14-1527-2017, https://doi.org/10.5194/bg-14-1527-2017, 2017
María Encina Aulló-Maestro, Peter Hunter, Evangelos Spyrakos, Pierre Mercatoris, Attila Kovács, Hajnalka Horváth, Tom Preston, Mátyás Présing, Jesús Torres Palenzuela, and Andrew Tyler
Biogeosciences, 14, 1215–1233, https://doi.org/10.5194/bg-14-1215-2017, https://doi.org/10.5194/bg-14-1215-2017, 2017
Short summary
Short summary
As first study within my PhD with the general objective to improve and adapt remote sensing algorithms for the estimation of coloured dissolved organic matter (CDOM) content in lakes in a global scale, we carried out this set of measurements and experiments.
This study gives us a better understanding of sources and variability in the optical properties of CDOM in lakes and how photobleaching controls and affects them.
Pratirupa Bardhan, Syed Wajih Ahmad Naqvi, Supriya G. Karapurkar, Damodar M. Shenoy, Siby Kurian, and Hema Naik
Biogeosciences, 14, 767–779, https://doi.org/10.5194/bg-14-767-2017, https://doi.org/10.5194/bg-14-767-2017, 2017
Short summary
Short summary
Although India has the third highest number of dams globally, there is a knowledge gap on the cycling of bioessential elements in such systems. This study (first of its kind) investigates the stable isotopes of nitrate and particulate organic matter in a pristine Indian reservoir. Nitrogen transformations in the anaerobic bottom waters were isotopically characterised. Overall, solar intensity, water depth and redox conditions are the major controls on the biogeochemical cycling in this system.
Bethany N. Deshpande, Sophie Crevecoeur, Alex Matveev, and Warwick F. Vincent
Biogeosciences, 13, 4411–4427, https://doi.org/10.5194/bg-13-4411-2016, https://doi.org/10.5194/bg-13-4411-2016, 2016
Short summary
Short summary
Subarctic lakes are changing in size as a result of permafrost thawing, resulting in mobilization of soil materials. Our study characterizes the carbon and nutrient regime of a set of thaw lakes and their adjacent permafrost soils in a rapidly degrading landscape, showing how these materials create favorable conditions for aquatic bacterial communities. We discuss the controls over the bacterial community, and demonstrate that gain processes are not a primary control.
Marloes Groeneveld, Lars Tranvik, Sivakiruthika Natchimuthu, and Birgit Koehler
Biogeosciences, 13, 3931–3943, https://doi.org/10.5194/bg-13-3931-2016, https://doi.org/10.5194/bg-13-3931-2016, 2016
Short summary
Short summary
Temporal variability in the apparent quantum yield of photochemical CDOM mineralisation in a boreal brown water lake was severalfold smaller than previously reported across different lakes. Simulated DIC photoproduction (2012–2014) averaged 2.0 ± 0.1 to 10.3 ± 0.7 g C m−2 yr−1 using the least and most reactive sample, which represented 1 to 8 % of the total mean CO2 emissions. Thus, direct CDOM photomineralisation makes only a minor contribution to mean CO2 emissions from Swedish brown water lakes.
Damien Bouffard and Marie-Elodie Perga
Biogeosciences, 13, 3573–3584, https://doi.org/10.5194/bg-13-3573-2016, https://doi.org/10.5194/bg-13-3573-2016, 2016
Short summary
Short summary
This survey of an exceptional flood over Lake Geneva challenges the long-standing hypothesis that dense, particle-loaded and oxygenated rivers plunging into lakes necessarily contribute to deep-oxygen replenishment. We identified some river intrusions as hot spots for oxygen consumption, where inputs of fresh river-borne organic matter reactivate the respiration of more refractory lacustrine organic matter in a process referred to as "priming effect".
Raquel Mendonça, Sarian Kosten, Sebastian Sobek, Simone Jaqueline Cardoso, Marcos Paulo Figueiredo-Barros, Carlos Henrique Duque Estrada, and Fábio Roland
Biogeosciences, 13, 3331–3342, https://doi.org/10.5194/bg-13-3331-2016, https://doi.org/10.5194/bg-13-3331-2016, 2016
Short summary
Short summary
Hydroelectric reservoirs in the tropics emit greenhouse gases but also bury carbon in their sediments. We investigated the efficiency of organic carbon (OC) burial in a large tropical reservoir, using spatially resolved measurements of sediment accumulation, and found that more than half (~ 57 %) of the OC deposited onto the sediment is buried. This high efficiency in OC burial indicates that tropical reservoirs may bury OC more efficiently than natural lakes.
Phil-Goo Kang, Myron J. Mitchell, Patrick J. McHale, Charles T. Driscoll, Shreeram Inamdar, and Ji-Hyung Park
Biogeosciences, 13, 2787–2801, https://doi.org/10.5194/bg-13-2787-2016, https://doi.org/10.5194/bg-13-2787-2016, 2016
Short summary
Short summary
Lakes play important roles in controlling organic matter derived from watersheds and within-lake production. The organic matter is normally measured by elemental quantities, such as carbon(C) and nitrogen(N), because the two elements are essential for aquatic ecosystems. We observed an decrease of C, but an increase of N in organic matters in a lake. The reason of the different pattern might be that inorganic N in the lake appeared to be recycled to produce organic N due to within-lake processes.
L. Pinho, C. M. Duarte, H. Marotta, and A. Enrich-Prast
Biogeosciences, 13, 865–871, https://doi.org/10.5194/bg-13-865-2016, https://doi.org/10.5194/bg-13-865-2016, 2016
Short summary
Short summary
Unlike the positive relationship reported before between partial pression of carbon dioxide and dissolved organic carbon for lake waters, we found no significant relationship in our low-latitude lakes, despite very broad ranges in both variables. The strength of this relationship declines with increasing water temperature, suggesting substantial differences in carbon cycling in warm lakes, which must be considered when upscaling limnetic carbon cycling to global scales.
S. G. Wakeham and E. A. Canuel
Biogeosciences, 13, 567–582, https://doi.org/10.5194/bg-13-567-2016, https://doi.org/10.5194/bg-13-567-2016, 2016
Short summary
Short summary
Bed sediments from the Sacramento-San Joaquin River Delta (CA) were fractionated according to density and analyzed for sediment mass distribution, elemental (C and N) composition, mineral surface area, and stable carbon and radiocarbon isotope compositions of organic carbon (OC) and fatty acids to evaluate the nature of organic carbon in river sediments. These data demonstrate the complex source and age distributions within river sediments.
B. Burpee, J. E. Saros, R. M. Northington, and K. S. Simon
Biogeosciences, 13, 365–374, https://doi.org/10.5194/bg-13-365-2016, https://doi.org/10.5194/bg-13-365-2016, 2016
Short summary
Short summary
This study investigates microbial nutrient limitation patterns across a region of southwest Greenland in relation to environmental factors. Using microbial enzyme activities to infer nutrient limitation patterns, we determined that most lakes are P-limited. Further, P limitation was tightly controlled by lake dissolved organic carbon (DOC) concentration.
A. Przytulska, J. Comte, S. Crevecoeur, C. Lovejoy, I. Laurion, and W. F. Vincent
Biogeosciences, 13, 13–26, https://doi.org/10.5194/bg-13-13-2016, https://doi.org/10.5194/bg-13-13-2016, 2016
Short summary
Short summary
Permafrost thaw lakes are a subject of increasing research interest given their abundance across the northern landscape. Our aim in the present study was to characterize the photosynthetic communities in a range of subarctic thaw lakes using a combination of HPLC analysis of algal and bacterial pigments, flow cytometry and molecular analysis. Our results showed that the thaw lakes contain diverse phototrophic communities and are a previously unrecognized habitat for abundant picophotoautotrophs.
T. Roiha, I. Laurion, and M. Rautio
Biogeosciences, 12, 7223–7237, https://doi.org/10.5194/bg-12-7223-2015, https://doi.org/10.5194/bg-12-7223-2015, 2015
Short summary
Short summary
Global warming thaws permafrost and accelerates the formation of thaw ponds in subarctic and arctic regions. These abundant ponds receive large terrestrial carbon inputs from the thawing and eroding permafrost, which is mainly used by bacterioplankton for the production of new biomass. Bacteria metabolism also produces high levels of CO2 and CH4, which make thaw ponds important sources of greenhouse gases to the atmosphere. We present carbon dynamics in thaw ponds in northern Quebec.
Cited articles
Anesio, A. M. and Granéli, W.: Increased photoreactivity of DOC by acidification: Implications for the carbon cycle in humic lakes, Limnol. Oceanogr., 48, 735–744, 2003.
Bertilsson, S. and Tranvik, L. J.: Photochemical transformation of dissolved organic matter in lakes, Limnol. Oceanogr., 45, 753–762, 2000
Brinkmann, T., Sartorius, D., and Frimmel, F. H.: Photobleaching of humic rich dissolved organic matter, Aquat. Sci., 65, 415–424, 2003.
Brooks, M. L., McKnight, D. M., and Clements, W. H.: Photochemical control of copper complexation by dissolved organic matter in Rocky Mountain streams, Colorado, Limnol. Oceanogr., 52, 766–779, 2007.
Brown, A. M.: A step-by-step guide to non-linear regression analysis of experimental data using a Microsoft Excel spreadsheet, Comput. Meth. Prog. Bio., 65, 191–200, 2001.
Cabaniss, S. E., Madey, G., Leff, L., Maurice, P. A., and Wetzel, R.: A stochastic model for the synthesis and degradation of natural organic matter. Part I. Data structures and reaction kinetics, Biogeochemistry, 76, 319–347, 2005.
Chin, Y. P., Aiken, G., and O'Loughlin, E.: Molecular Weight, Polydispersity, and Spectroscopic Properties of Aquatic Humic Substances, Environ. Sci. Technol., 28, 1853–1858, 1994.
Devito, K. J. and Dillon, P. J.: Importance of runoff and winter anoxia to the P and N dynamics of a beaver pond, Can. J. Fish. Aquat. Sci., 50, 2222–2234, 1993.
Dillon, P. J. and Molot, L. A.: Dissolved organic and inorganic carbon mass balances in central Ontario lakes, Biogeochemistry, 36, 29–42, 1997a.
Dillon, P. J. and Molot, L. A.: Effect of landscape form on export of dissolved organic carbon, iron, and phosphorus from forested stream catchments, Water Resour. Res., 33, 2591–2600, 1997b.
Dillon, P. J., Molot, L. A., and Scheider, W. A.: Phosphorus and Nitrogen Export from Forested Stream Catchments in Central Ontario, J. Environ. Qual., 20, 857–864, 1991.
Eimers, M. C., Buttle, J. and Watmough, S. A.: Influence of seasonal changes in runoff and extreme events on dissolved organic carbon trends in wetland- and upland-draining streams, Can. J. Fish. Aquat. Sci., 65, 796–808, 2008.
Escobedo, J. F., Gomes, E. N., Oliveira, A. P., and Soares, J.: Ratios of UV, PAR and NIR components to global solar radiation measured at Botucatu site in Brazil, Renew. Energ., 1, 169–178, https://doi.org/10.1016/j.renene.2010.06.018, 2011.
Freeman, C., Fenner, N., Ostle, N. J., Kang, H., Dowrick, D. J., Reynolds, B., Lock, M. A., Sleep, D., Hughes, S., and Hudson, J.: Export of dissolved organic carbon from peatlands under elevated carbon dioxide levels, Nature, 430, 195–198, 2004.
Frost, P. C., Larson, J. H., Kinsman, L. E., and Bridgham, S. D.: Attenuation of ultraviolet radiation in streams of northern Michigan, J. N. Am. Benthol. Soc., 24, 246–255, 2005.
Gao, H. and Zepp, R. G.: Factors Influencing Photoreactions of Dissolved Organic Matter in a Coastal River of the Southeastern United States, Environ. Sci. Technol., 32, 2940–2946, 1998
Gennings, C., Molot, L. A., and Dillon, P. J.: Enhanced photochemical loss of organic carbon in acidic waters, Biogeochemistry, 52, 339–354, 2001.
Glaeser, J., Nuss, A. M., Berghoff, B. A., and Klug, G.: Singlet Oxygen Stress in Microorganisms, Adv. Microb. Physiol., 58, 141–173, 2011.
Granéli, W., Lindell, M., and Tranvik, L.: Photo-oxidative production of dissolved inorganic carbon in lakes of different humic content, Limnol. Oceanogr., 41, 698–706, 1996.
Köhler, S., Buffam, I., Jonsson, A., and Bishop, K.: Photochemical and microbial processing of stream and soil water dissolved organic matter in a boreal forested catchment in northern Sweden, Aquat. Sci., 64, 269–281, 2002.
Kothawala, D., Evans, R. D., and Dillon, P. J.: Changes in the molecular weight distribution of dissolved organic carbon within a Precambrian Shield stream, Water Resour. Res., 42, W05401, https://doi.org/10.1029/2005WR004441, 2006.
Laudon, H., Köhler, S., and Buffam, I.: Seasonal TOC export from seven boreal catchments in northern Sweden, Aquat. Sci., 66, 223–230, 2004.
Lindell, M. J., Granéli, H. W., and Bertilsson, S.: Seasonal photoreactivity of dissolved organic matter from lakes with contrasting humic content, Can. J. Fish. Aquat. Sci., 57, 875–885, 2000.
Mantoura, R. F. C., Dickson, A., and Riley, J. P.: The complexation of metals with humic materials in natural waters, Estuar. Coast. Mar. Sci., 6, 387–408, 1978.
Miller, W. L. and Moran, M. A.: Interaction of photochemical and microbial processes in the degradation of refractory dissolved organic matter from a coastal marine environment, Limnol. Oceanogr., 42, 1317–1324, 1997.
Molot, L. A. and Dillon, P. J.: Photolytic regulation of dissolved organic carbon in northern lakes, Global Biochem. Cy., 11, 351–365, 1997.
Molot, L. A., Hudson, J. J., Dillon, P. J., and Miller, S. A.: Effect of pH on photo-oxidation of dissolved organic carbon by hydroxyl radicals in a coloured, softwater stream, Aquat. Sci., 67, 189–195, 2005.
Mulholland, P. J. and Hill, W. R.: Seasonal patterns in streamwater nutrient and dissolved organic carbon concentrations: Separating catchment flow path and in-stream effects, Water Resour. Res., 33, 1297–1306, 1997.
Perdue, E. M.: Chemical composition, structure, and metal binding properties, in: Aquatic humic substances, edited by: Hessen, D. O. and Tranvik, L. J., Springer-Verlag, Berlin Heidelberg, 41–61, 1998.
Petty, G. W.: A first course in atmospheric radiation, 2nd Edn., Sundog Publishing, Madison, Wisconsin, USA, 2006.
Porcal, P., Hejzlar, J., and Kopáček, J.: Seasonal and photochemical changes of DOM in an acidified forest lake and its tributaries, Aquat. Sci., 66, 211–222, 2004.
Porcal, P., Koprivnjak, J. F., Molot, L. A., and Dillon, P. J.: Humic substances – part 7: the biogeochemistry of dissolved organic carbon and its interactions with climate change, Environ. Sci. Pollut. Res., 16, 714–726, 2009.
Porcal, P., Amirbahman, A., Kopáček, J., and Norton, S. A.: Experimental photochemical release of organically bound aluminum and iron in three streams in Maine, USA, Environ. Monit. Assess., 171, 71–81, https://doi.org/10.1007/s10661-010-1529-x, 2010.
Porcal, P., Dillon, P. J., and Molot, L. A.: Photochemical production and decomposition of particulate organic carbon in a freshwater stream, Aquat. Sci., https://doi.org/10.1007/s00027-013-0293-8, 2013.
Ruiz-Gonzáles, C., Simó, R., Sommaruga, R., and Gasol, J. M.: Away from darkness: A review on the effects of solar radiation on heterotrophic bacterioplankron activity, Front. Microbiol., 4, https://doi.org/10.3389/fmicb.2013.00131, 2013
Salonen, K. and Vähätalo, A.: Photochemical mineralisation of dissolved organic matter in Lake Skervatjern, Environ. Int., 20, 307–312, 1994.
Scully, N. M., Cooper, W. J., and Tranvik, L. J.: Photochemical effects on microbial activity in natural waters: the interaction of reactive oxygen species and dissolved organic matter, FEMS Microbiol. Ecol., 46, 353–357, 2003
Suhett, A. L., Amado, A. M., Enrich-Prast, A., de Assis, E. F., and Farjalla, V. F.: Seasonla changes of dissolved organic carbon photo-oxidation rates in a tropical humic lagoon: the role of rainfall as a major regulator, Can. J. Fish. Aquat. Sci., 64, 1266–1272, 2007.
Twardowski, M. S. and Donaghay, P. L.: Photobleaching of aquatic dissolved materials: Absorption removal, spectral alteration, and their interrelationship, J. Geophys. Res., 107, 3091, https://doi.org/10.1029/1999JC000281, 2002.
Vähätalo, A., Salkinoja-Salonen, M., Taalas, P., and Salonen, K.: Spectrum of the quantum yield for photochemical mineralization of dissolved organic carbon in a humic lake, Limnol. Oceanogr., 45, 664–676, 2000.
Vance, G. F., Stevenson, F. J., and Sikora, F. J.: Environmental chemistry of aluminum-organic complexes, in: The environmental chemistry of aluminum, edited by: Sposito, G., Lewis Publishers, Chelsea, 169–220, 1996.
Von Wachenfeldt, E., Sobek, S., Bastviken, D., and Tranvik, L. J.: Linking allochthonous dissolved organic matter and boreal lake sediment carbon sequestration: The role of light-mediated flocculation, Limnol. Oceanogr., 53, 2416–2426, 2008.
Vuorenmaa, J., Forsius, M., and Mannio, J.: Increasing trends of total organic carbon concentrations in small forest lakes in Finland from 1987 to 2003, Sci. Total Environ., 365, 47–65, 2006.
Wang, W., Tarr, M. A., Bianchi, T. S., and Engelhaupt, E.: Ammonium Photoproduction from Aquatic Humic and Colloidal Matter, Aquat. Geochem., 6, 275–292, 2000.
Weishaar, J. L., Aiken, G. R., Bergamashi, B. A., Fram, M. R., Fujii, R., and Mopper, K.: Evaluation of Specific Ultraviolet Absorbance as an Indicator of the Chemical Composition and Reactivity of Dissolved Organic Carbon, Environ. Sci. Technol., 37, 4702–4708, 2003.
Wetzel, R. G., Hatcher, P. G., and Bianchi, T. S.: Natural photolysis by ultraviolet irradiance of recalcitrant dissolved organic matter to simple substrates for rapid bacterial metabolism, Limnol. Oceanogr., 40, 1369–1380, 1995.
Worrall, F., Harriman, R., Evans, C. D., Watts, C. D., Adamson, J., Neal, C., Tipping, E., Burt, T., Grieve, I., Monteith, D., Naden, P. S., Nisbet, T., Reynolds, B., and Stevens, P.: Review of riverine DOC trends in the UK, Biogeochemistry, 70, 369–402, 2004.
Wu, F. C., Evans, R. D., and Dillon, P. J.: Separation and Characterization of NOM by High-Performance Liquid Chromatography and On-Line Three-Dimensional Excitation Emission Matrix Fluorescence Detection, Environ. Sci. Technol., 37, 3687–3693, 2003.
Zepp, R. G., Wolfe, N. L., Baughman, G. L., and Hollis, R. C.: Singlet oxygen in natural waters, Nature, 267, 421–423, 1977.
