Articles | Volume 17, issue 18
https://doi.org/10.5194/bg-17-4707-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-17-4707-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
28 Sep 2020
Research article |
| 28 Sep 2020
| 28 Sep 2020
Reconstructing extreme climatic and geochemical conditions during the largest natural mangrove dieback on record
James Z. Sippo
CORRESPONDING AUTHOR
Southern Cross GeoScience, Southern Cross University, Lismore 2480, Australia
National Marine Science Centre, Southern Cross University, P.O. Box 4321, Coffs Harbour, NSW 2450, Australia
Isaac R. Santos
National Marine Science Centre, Southern Cross University, P.O. Box 4321, Coffs Harbour, NSW 2450, Australia
Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden
Christian J. Sanders
National Marine Science Centre, Southern Cross University, P.O. Box 4321, Coffs Harbour, NSW 2450, Australia
Patricia Gadd
Australian Nuclear Science and Technology Organisation (ANSTO), Locked Bag 2001, Kirrawee DC, NSW 2232, Australia
Quan Hua
Australian Nuclear Science and Technology Organisation (ANSTO), Locked Bag 2001, Kirrawee DC, NSW 2232, Australia
Catherine E. Lovelock
School of Biological Sciences, the University of Queensland, St Lucia, QLD 4072, Australia
Nadia S. Santini
Cátedra Consejo Nacional de Ciencia y Tecnología, Av. Insurgentes Sur 1582, Crédito Constructor, Benito Juárez 03940, Ciudad de México, Mexico
Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04500, Ciudad de México, Mexico
Scott G. Johnston
Southern Cross GeoScience, Southern Cross University, Lismore 2480, Australia
Yota Harada
Australian Rivers Institute – Coast and Estuaries, and School of Environment and Science, Griffith University, Gold Coast, QLD 4222, Australia
Gloria Reithmeir
Southern Cross GeoScience, Southern Cross University, Lismore 2480, Australia
Damien T. Maher
Southern Cross GeoScience, Southern Cross University, Lismore 2480, Australia
School of Environment, Science and Engineering, Southern Cross University, Lismore 2480, Australia
Related authors
No articles found.
Benjamin Hmiel, Vasilii V. Petrenko, Christo Buizert, Andrew M. Smith, Michael N. Dyonisius, Philip Place, Bin Yang, Quan Hua, Ross Beaudette, Jeffrey P. Severinghaus, Christina Harth, Ray F. Weiss, Lindsey Davidge, Melisa Diaz, Matthew Pacicco, James A. Menking, Michael Kalk, Xavier Faïn, Alden Adolph, Isaac Vimont, and Lee T. Murray
The Cryosphere Discuss., https://doi.org/10.5194/tc-2023-121, https://doi.org/10.5194/tc-2023-121, 2023
Revised manuscript accepted for TC
Short summary
Short summary
The main aim of this research is to improve understanding of carbon-14 that is produced by cosmic rays in ice sheets. Measurements of carbon-14 in ice cores can provide a range of useful information (age of ice, past atmospheric chemistry, past cosmic ray intensity). Our results show that almost all (approx. 95 %) of carbon-14 that is produced in the upper layer of ice sheets is rapidly lost to the atmosphere. Our results also provide better estimates of carbon-14 production rates in deeper ice.
Naima Iram, Emad Kavehei, Damien T. Maher, Stuart E. Bunn, Mehran Rezaei Rashti, Bahareh Shahrabi Farahani, and Maria Fernanda Adame
Biogeosciences, 18, 5085–5096, https://doi.org/10.5194/bg-18-5085-2021, https://doi.org/10.5194/bg-18-5085-2021, 2021
Short summary
Short summary
Greenhouse gas emissions were measured and compared from natural coastal wetlands and their converted agricultural lands across annual seasonal cycles in tropical Australia. Ponded pastures emitted ~ 200-fold-higher methane than any other tested land use type, suggesting the highest greenhouse gas mitigation potential and financial incentives by the restoration of ponded pastures to natural coastal wetlands.
Dylan R. Brown, Humberto Marotta, Roberta B. Peixoto, Alex Enrich-Prast, Glenda C. Barroso, Mario L. G. Soares, Wilson Machado, Alexander Pérez, Joseph M. Smoak, Luciana M. Sanders, Stephen Conrad, James Z. Sippo, Isaac R. Santos, Damien T. Maher, and Christian J. Sanders
Biogeosciences, 18, 2527–2538, https://doi.org/10.5194/bg-18-2527-2021, https://doi.org/10.5194/bg-18-2527-2021, 2021
Short summary
Short summary
Hypersaline tidal flats (HTFs) are coastal ecosystems with freshwater deficits often occurring in arid or semi-arid regions near mangrove supratidal zones with no major fluvial contributions. This study shows that HTFs are important carbon and nutrient sinks which may be significant given their extensive coverage. Our findings highlight a previously unquantified carbon as well as a nutrient sink and suggest that coastal HTF ecosystems could be included in the emerging blue carbon framework.
Vasilii V. Petrenko, Andrew M. Smith, Edward M. Crosier, Roxana Kazemi, Philip Place, Aidan Colton, Bin Yang, Quan Hua, and Lee T. Murray
Atmos. Meas. Tech., 14, 2055–2063, https://doi.org/10.5194/amt-14-2055-2021, https://doi.org/10.5194/amt-14-2055-2021, 2021
Short summary
Short summary
This paper presents an improved methodology for measurements of atmospheric concentration of carbon-14-containing carbon monoxide (14CO), as well as a 1-year dataset that demonstrates the methodology. Atmospheric 14CO concentration measurements are useful for improving the understanding of spatial and temporal variability of hydroxyl radical concentrations. Key improvements over prior methods include a greatly reduced air sample size and accurate procedural blank characterization.
Yota Harada, Rod M. Connolly, Brian Fry, Damien T. Maher, James Z. Sippo, Luke C. Jeffrey, Adam J. Bourke, and Shing Yip Lee
Biogeosciences, 17, 5599–5613, https://doi.org/10.5194/bg-17-5599-2020, https://doi.org/10.5194/bg-17-5599-2020, 2020
Short summary
Short summary
In 2015–2016, an extensive area of mangroves along ~ 1000 km of coastline in the Gulf of Carpentaria, Australia, experienced dieback as a result of a climatic extreme event that included drought conditions and low sea levels. Multiannual field campaigns conducted from 2016 to 2018 show substantial recovery of the mangrove vegetation. However, stable isotopes suggest long-lasting changes in carbon, nitrogen and sulfur cycling following the dieback.
Sabina Yeasmin, Balwant Singh, Cliff T. Johnston, Donald L. Sparks, and Quan Hua
Biogeosciences Discuss., https://doi.org/10.5194/bg-2019-416, https://doi.org/10.5194/bg-2019-416, 2019
Preprint withdrawn
Short summary
Short summary
This study demonstrated impact of land use change on organic carbon (OC) pools in four soils with contrasting mineralogy for both surface and sub-surface depths. Bulk soils were isolated into particulate and mineral associated OC by density fractionation, and analysed for mineralogy, OC, nitrogen and isotopic signatures. Results reveal that quantity and quality of OC after land use change was influenced by nature of C input in surface soils and by mineral-organic association in sub-surface soils.
Agathe Lisé-Pronovost, Michael-Shawn Fletcher, Tom Mallett, Michela Mariani, Richard Lewis, Patricia S. Gadd, Andy I. R. Herries, Maarten Blaauw, Hendrik Heijnis, Dominic A. Hodgson, and Joel B. Pedro
Sci. Dril., 25, 1–14, https://doi.org/10.5194/sd-25-1-2019, https://doi.org/10.5194/sd-25-1-2019, 2019
Short summary
Short summary
We present the first results from scientific drilling at Darwin Crater, a 816 000-year-old meteorite impact crater in Tasmania. The aim was to recover lacustrine sediments in the crater to reconstruct paleoclimate and bridge a time gap in understanding climate change in mid-latitude Australia. The multi-proxy dataset provides clear signatures of alternating glacial and interglacial lithologies, promising for investigating the role of the Southern Hemisphere westerly winds in Pleistocene climate.
Luke C. Jeffrey, Damien T. Maher, Scott G. Johnston, Kylie Maguire, Andrew D. L. Steven, and Douglas R. Tait
Biogeosciences, 16, 1799–1815, https://doi.org/10.5194/bg-16-1799-2019, https://doi.org/10.5194/bg-16-1799-2019, 2019
Short summary
Short summary
Wetlands represent the largest natural source of methane (CH4), so understanding CH4 drivers is important for management and climate models. We compared several CH4 pathways of a remediated subtropical Australian wetland. We found permanently inundated sites emitted more CH4 than seasonally inundated sites and that the soil properties of each site corresponded to CH4 emissions. This suggests that selective wetland remediation of favourable soil types may help to mitigate unwanted CH4 emissions.
Ariane Arias-Ortiz, Pere Masqué, Jordi Garcia-Orellana, Oscar Serrano, Inés Mazarrasa, Núria Marbà, Catherine E. Lovelock, Paul S. Lavery, and Carlos M. Duarte
Biogeosciences, 15, 6791–6818, https://doi.org/10.5194/bg-15-6791-2018, https://doi.org/10.5194/bg-15-6791-2018, 2018
Short summary
Short summary
Efforts to include tidal marsh, mangrove and seagrass ecosystems in existing carbon mitigation strategies are limited by a lack of estimates of carbon accumulation rates (CARs). We discuss the use of 210Pb dating to determine CARs in these habitats, which are often composed of heterogeneous sediments and affected by sedimentary processes. Results show that obtaining reliable geochronologies in these systems is ambitious, but estimates of mean 100-year CARs are mostly secure within 20 % error.
Alistair Grinham, Simon Albert, Nathaniel Deering, Matthew Dunbabin, David Bastviken, Bradford Sherman, Catherine E. Lovelock, and Christopher D. Evans
Hydrol. Earth Syst. Sci., 22, 5281–5298, https://doi.org/10.5194/hess-22-5281-2018, https://doi.org/10.5194/hess-22-5281-2018, 2018
Short summary
Short summary
Artificial water bodies are a major source of methane and an important contributor to flooded land greenhouse gas emissions. Past studies focussed on large water supply or hydropower reservoirs with small artificial water bodies (ponds) almost completely ignored. This regional study demonstrated ponds accounted for one-third of flooded land surface area and emitted over 1.6 million t CO2 eq. yr−1 (10 % of land use sector emissions). Ponds should be included in regional GHG inventories.
Julie A. Trotter, Charitha Pattiaratchi, Paolo Montagna, Marco Taviani, James Falter, Ron Thresher, Andrew Hosie, David Haig, Federica Foglini, Quan Hua, and Malcolm T. McCulloch
Biogeosciences Discuss., https://doi.org/10.5194/bg-2018-319, https://doi.org/10.5194/bg-2018-319, 2018
Manuscript not accepted for further review
Short summary
Short summary
The first ROV exploration of the Perth Canyon offshore southwest Australia discovered diverse
hot spotsof deep-sea biota to depths of ~ 2000 m. Some corals were living below the carbonate saturation horizon. Extensive coral graveyards found at ~ 700 and ~ 1700 m are between ~ 18 000 and ~ 30 000 years old, indicating these corals flourished during the last ice age. Anthropogenic carbon detected within the upper ~ 800 m highlights the increasing threat of climate change to deep-sea ecosystems.
Luciana M. Sanders, Kathryn Taffs, Debra Stokes, Christian J. Sanders, Alex Enrich-Prast, Leonardo Amora-Nogueira, and Humberto Marotta
Biogeosciences, 15, 447–455, https://doi.org/10.5194/bg-15-447-2018, https://doi.org/10.5194/bg-15-447-2018, 2018
Short summary
Short summary
The Amazon rainforest produce large quantities of carbon, a portion of which is deposited in floodplain lakes. This research shows a potentially important spatial dependence of the carbon deposition in the Amazon lacustrine sediments in relation to deforestation rates in the catchment. The findings presented here highlight the effects of abrupt and temporary events in which some of the biomass released by the deforestation reach the depositional environments in the Amazon floodplains.
Mitchell Call, Kai G. Schulz, Matheus C. Carvalho, Isaac R. Santos, and Damien T. Maher
Biogeosciences, 14, 1305–1313, https://doi.org/10.5194/bg-14-1305-2017, https://doi.org/10.5194/bg-14-1305-2017, 2017
Short summary
Short summary
The conventional method for determining dissolved inorganic carbon (DIC) and it carbon stable isotope ratio (δ13C–DIC) can be a laborious process which can limit sampling frequency. This paper presents a new approach to autonomously determine DIC & δ13C–DIC at high temporal resolution. The simple method requires no customised design. Instead it uses two commercially available instruments and achieved a sampling resolution of 16 mins with precision and accuracy comparable to conventional methods.
I. Mazarrasa, N. Marbà, C. E. Lovelock, O. Serrano, P. S. Lavery, J. W. Fourqurean, H. Kennedy, M. A. Mateo, D. Krause-Jensen, A. D. L. Steven, and C. M. Duarte
Biogeosciences, 12, 4993–5003, https://doi.org/10.5194/bg-12-4993-2015, https://doi.org/10.5194/bg-12-4993-2015, 2015
Short summary
Short summary
There has been growing interest in quantifying the capacity of seagrass ecosystems to act as carbon sinks as a natural way of offsetting anthropogenic carbon emissions to the atmosphere. However, most of the efforts have focused on the organic fraction and ignored the inorganic carbon pool. This study offers the first global assessment of PIC stocks and accumulation rates in seagrass sediments, identifying these ecosystems as important contributors to carbonate dynamics in coastal areas.
M. F. Adame, N. S. Santini, C. Tovilla, A. Vázquez-Lule, L. Castro, and M. Guevara
Biogeosciences, 12, 3805–3818, https://doi.org/10.5194/bg-12-3805-2015, https://doi.org/10.5194/bg-12-3805-2015, 2015
Short summary
Short summary
Riverine wetlands of the south Pacific coast of Mexico had large ecosystem C stocks (784.5 MgC ha-1 for mangroves, 722.2 MgC ha-1 for peat swamps, and 336.5 MgC ha-1 for marshes). Long-term soil C sequestration values in mangroves were 1.3 ± 0.2 MgC ha-1yr-1. C stocks, and soil nitrogen stocks were in general larger for mangroves in the upper than in the lower estuary.
B. D. Eyre, I. R. Santos, and D. T. Maher
Biogeosciences, 10, 2601–2615, https://doi.org/10.5194/bg-10-2601-2013, https://doi.org/10.5194/bg-10-2601-2013, 2013
T. Cyronak, I. R. Santos, D. V. Erler, and B. D. Eyre
Biogeosciences, 10, 2467–2480, https://doi.org/10.5194/bg-10-2467-2013, https://doi.org/10.5194/bg-10-2467-2013, 2013
Related subject area
Biogeochemistry: Coastal Ocean
Ocean alkalinity enhancement using sodium carbonate salts does not lead to measurable changes in Fe dynamics in a mesocosm experiment
Quantification and mitigation of bottom-trawling impacts on sedimentary organic carbon stocks in the North Sea
Influence of ocean alkalinity enhancement with olivine or steel slag on a coastal plankton community in Tasmania
Multi-model comparison of trends and controls of near-bed oxygen concentration on the northwest European continental shelf under climate change
Picoplanktonic methane production in eutrophic surface waters
Vertical mixing alleviates autumnal oxygen deficiency in the central North Sea
Hypoxia also occurs in small highly turbid estuaries: the example of the Charente (Bay of Biscay)
Seasonality and response of ocean acidification and hypoxia to major environmental anomalies in the southern Salish Sea, North America (2014–2018)
Oceanographic processes driving low-oxygen conditions inside Patagonian fjords
Above- and belowground plant mercury dynamics in a salt marsh estuary in Massachusetts, USA
Variability and drivers of carbonate chemistry at shellfish aquaculture sites in the Salish Sea, British Columbia
Unusual Hemiaulus bloom influences ocean productivity in Northeastern US Shelf waters
Insights into carbonate environmental conditions in the Chukchi Sea
UAV approaches for improved mapping of vegetation cover and estimation of carbon storage of small saltmarshes: examples from Loch Fleet, northeast Scotland
Iron “ore” nothing: benthic iron fluxes from the oxygen-deficient Santa Barbara Basin enhance phytoplankton productivity in surface waters
Marine anoxia initiates giant sulfur-oxidizing bacterial mat proliferation and associated changes in benthic nitrogen, sulfur, and iron cycling in the Santa Barbara Basin, California Borderland
Uncertainty in the evolution of northwestern North Atlantic circulation leads to diverging biogeochemical projections
The additionality problem of ocean alkalinity enhancement
Short-term variation in pH in seawaters around coastal areas of Japan: characteristics and forcings
Revisiting the applicability and constraints of molybdenum- and uranium-based paleo redox proxies: comparing two contrasting sill fjords
Influence of a small submarine canyon on biogenic matter export flux in the lower St. Lawrence Estuary, eastern Canada
Single-celled bioturbators: benthic foraminifera mediate oxygen penetration and prokaryotic diversity in intertidal sediment
Assessing impacts of coastal warming, acidification, and deoxygenation on Pacific oyster (Crassostrea gigas) farming: a case study in the Hinase area, Okayama Prefecture, and Shizugawa Bay, Miyagi Prefecture, Japan
Distribution of nutrients and dissolved organic matter in a eutrophic equatorial estuary, the Johor River and East Johor Strait
The estimates of carbon sequestration potential in an expanding Arctic fjord affected by dark plumes of glacial meltwater (Hornsund, Svalbard)
Multiple nitrogen sources for primary production inferred from δ13C and δ15N in the southern Sea of Japan
Investigating the effect of silicate and calcium based ocean alkalinity enhancement on diatom silicification
Influence of manganese cycling on alkalinity in the redox stratified water column of Chesapeake Bay
Estuarine flocculation dynamics of organic carbon and metals from boreal acid sulfate soils
Drivers of particle sinking velocities in the Peruvian upwelling system
Impacts and uncertainties of climate-induced changes in watershed inputs on estuarine hypoxia
Considerations for hypothetical carbon dioxide removal via alkalinity addition in the Amazon River watershed
High metabolism and periodic hypoxia associated with drifting macrophyte detritus in the shallow subtidal Baltic Sea
Production and accumulation of reef framework by calcifying corals and macroalgae on a remote Indian Ocean cay
Zooplankton community succession and trophic links during a mesocosm experiment in the coastal upwelling off Callao Bay (Peru)
Temporal and spatial evolution of bottom-water hypoxia in the St Lawrence estuarine system
Significant nutrient consumption in the dark subsurface layer during a diatom bloom: a case study on Funka Bay, Hokkaido, Japan
Contrasts in dissolved, particulate, and sedimentary organic carbon from the Kolyma River to the East Siberian Shelf
Sediment quality assessment in an industrialized Greek coastal marine area (western Saronikos Gulf)
Limits and CO2 equilibration of near-coast alkalinity enhancement
Role of phosphorus in the seasonal deoxygenation of the East China Sea shelf
Interannual variability of the initiation of the phytoplankton growing period in two French coastal ecosystems
Spatio-temporal distribution, photoreactivity and environmental control of dissolved organic matter in the sea-surface microlayer of the eastern marginal seas of China
Metabolic alkalinity release from large port facilities (Hamburg, Germany) and impact on coastal carbon storage
A Numerical reassessment of the Gulf of Mexico carbon system in connection with the Mississippi River and global ocean
Observed and projected global warming pressure on coastal hypoxia
Benthic alkalinity fluxes from coastal sediments of the Baltic and North seas: comparing approaches and identifying knowledge gaps
Investigating the effect of nickel concentration on phytoplankton growth to assess potential side-effects of ocean alkalinity enhancement
Unprecedented summer hypoxia in southern Cape Cod Bay: an ecological response to regional climate change?
Interannual variabilities, long-term trends, and regulating factors of low-oxygen conditions in the coastal waters off Hong Kong
David González-Santana, María Segovia, Melchor González-Dávila, Librada Ramírez, Aridane G. González, Leonardo J. Pozzo-Pirotta, Veronica Arnone, Victor Vázquez, Ulf Riebesell, and J. Magdalena Santana-Casiano
Biogeosciences, 21, 2705–2715, https://doi.org/10.5194/bg-21-2705-2024, https://doi.org/10.5194/bg-21-2705-2024, 2024
Short summary
Short summary
In a recent experiment off the coast of Gran Canaria (Spain), scientists explored a method called ocean alkalinization enhancement (OAE), where carbonate minerals were added to seawater. This process changed the levels of certain ions in the water, affecting its pH and buffering capacity. The researchers were particularly interested in how this could impact the levels of essential trace metals in the water.
Lucas Porz, Wenyan Zhang, Nils Christiansen, Jan Kossack, Ute Daewel, and Corinna Schrum
Biogeosciences, 21, 2547–2570, https://doi.org/10.5194/bg-21-2547-2024, https://doi.org/10.5194/bg-21-2547-2024, 2024
Short summary
Short summary
Seafloor sediments store a large amount of carbon, helping to naturally regulate Earth's climate. If disturbed, some sediment particles can turn into CO2, but this effect is not well understood. Using computer simulations, we found that bottom-contacting fishing gears release about 1 million tons of CO2 per year in the North Sea, one of the most heavily fished regions globally. We show how protecting certain areas could reduce these emissions while also benefitting seafloor-living animals.
Jiaying A. Guo, Robert F. Strzepek, Kerrie M. Swadling, Ashley T. Townsend, and Lennart T. Bach
Biogeosciences, 21, 2335–2354, https://doi.org/10.5194/bg-21-2335-2024, https://doi.org/10.5194/bg-21-2335-2024, 2024
Short summary
Short summary
Ocean alkalinity enhancement aims to increase atmospheric CO2 sequestration by adding alkaline materials to the ocean. We assessed the environmental effects of olivine and steel slag powder on coastal plankton. Overall, slag is more efficient than olivine in releasing total alkalinity and, thus, in its ability to sequester CO2. Slag also had less environmental effect on the enclosed plankton communities when considering its higher CO2 removal potential based on this 3-week experiment.
Giovanni Galli, Sarah Wakelin, James Harle, Jason Holt, and Yuri Artioli
Biogeosciences, 21, 2143–2158, https://doi.org/10.5194/bg-21-2143-2024, https://doi.org/10.5194/bg-21-2143-2024, 2024
Short summary
Short summary
This work shows that, under a high-emission scenario, oxygen concentration in deep water of parts of the North Sea and Celtic Sea can become critically low (hypoxia) towards the end of this century. The extent and frequency of hypoxia depends on the intensity of climate change projected by different climate models. This is the result of a complex combination of factors like warming, increase in stratification, changes in the currents and changes in biological processes.
Sandy E. Tenorio and Laura Farías
Biogeosciences, 21, 2029–2050, https://doi.org/10.5194/bg-21-2029-2024, https://doi.org/10.5194/bg-21-2029-2024, 2024
Short summary
Short summary
Time series studies show that CH4 is highly dynamic on the coastal ocean surface and planktonic communities are linked to CH4 accumulation, as found in coastal upwelling off Chile. We have identified the crucial role of picoplankton (> 3 µm) in CH4 recycling, especially with the addition of methylated substrates (trimethylamine and methylphosphonic acid) during upwelling and non-upwelling periods. These insights improve understanding of surface ocean CH4 recycling, aiding CH4 emission estimates.
Charlotte A. J. Williams, Tom Hull, Jan Kaiser, Claire Mahaffey, Naomi Greenwood, Matthew Toberman, and Matthew R. Palmer
Biogeosciences, 21, 1961–1971, https://doi.org/10.5194/bg-21-1961-2024, https://doi.org/10.5194/bg-21-1961-2024, 2024
Short summary
Short summary
Oxygen (O2) is a key indicator of ocean health. The risk of O2 loss in the productive coastal/continental slope regions is increasing. Autonomous underwater vehicles equipped with O2 optodes provide lots of data but have problems resolving strong vertical O2 changes. Here we show how to overcome this and calculate how much O2 is supplied to the low-O2 bottom waters via mixing. Bursts in mixing supply nearly all of the O2 to bottom waters in autumn, stopping them reaching ecologically low levels.
Sabine Schmidt and Ibrahima Iris Diallo
Biogeosciences, 21, 1785–1800, https://doi.org/10.5194/bg-21-1785-2024, https://doi.org/10.5194/bg-21-1785-2024, 2024
Short summary
Short summary
Along the French coast facing the Bay of Biscay, the large Gironde and Loire estuaries suffer from hypoxia. This prompted a study of the small Charente estuary located between them. This work reveals a minimum oxygen zone in the Charente estuary, which extends for about 25 km. Temperature is the main factor controlling the hypoxia. This calls for the monitoring of small turbid macrotidal estuaries that are vulnerable to hypoxia, a risk expected to increase with global warming.
Simone R. Alin, Jan A. Newton, Richard A. Feely, Samantha Siedlecki, and Dana Greeley
Biogeosciences, 21, 1639–1673, https://doi.org/10.5194/bg-21-1639-2024, https://doi.org/10.5194/bg-21-1639-2024, 2024
Short summary
Short summary
We provide a new multi-stressor data product that allows us to characterize the seasonality of temperature, O2, and CO2 in the southern Salish Sea and delivers insights into the impacts of major marine heatwave and precipitation anomalies on regional ocean acidification and hypoxia. We also describe the present-day frequencies of temperature, O2, and ocean acidification conditions that cross thresholds of sensitive regional species that are economically or ecologically important.
Pamela Linford, Iván Pérez-Santos, Paulina Montero, Patricio A. Díaz, Claudia Aracena, Elías Pinilla, Facundo Barrera, Manuel Castillo, Aida Alvera-Azcárate, Mónica Alvarado, Gabriel Soto, Cécile Pujol, Camila Schwerter, Sara Arenas-Uribe, Pilar Navarro, Guido Mancilla-Gutiérrez, Robinson Altamirano, Javiera San Martín, and Camila Soto-Riquelme
Biogeosciences, 21, 1433–1459, https://doi.org/10.5194/bg-21-1433-2024, https://doi.org/10.5194/bg-21-1433-2024, 2024
Short summary
Short summary
The Patagonian fjords comprise a world region where low-oxygen water and hypoxia conditions are observed. An in situ dataset was used to quantify the mechanism involved in the presence of these conditions in northern Patagonian fjords. Water mass analysis confirmed the contribution of Equatorial Subsurface Water in the advection of the low-oxygen water, and hypoxic conditions occurred when the community respiration rate exceeded the gross primary production.
Ting Wang, Buyun Du, Inke Forbrich, Jun Zhou, Joshua Polen, Elsie M. Sunderland, Prentiss H. Balcom, Celia Chen, and Daniel Obrist
Biogeosciences, 21, 1461–1476, https://doi.org/10.5194/bg-21-1461-2024, https://doi.org/10.5194/bg-21-1461-2024, 2024
Short summary
Short summary
The strong seasonal increases of Hg in aboveground biomass during the growing season and the lack of changes observed after senescence in this salt marsh ecosystem suggest physiologically controlled Hg uptake pathways. The Hg sources found in marsh aboveground tissues originate from a mix of sources, unlike terrestrial ecosystems, where atmospheric GEM is the main source. Belowground plant tissues mostly take up Hg from soils. Overall, the salt marsh currently serves as a small net Hg sink.
Eleanor Simpson, Debby Ianson, Karen E. Kohfeld, Ana C. Franco, Paul A. Covert, Marty Davelaar, and Yves Perreault
Biogeosciences, 21, 1323–1353, https://doi.org/10.5194/bg-21-1323-2024, https://doi.org/10.5194/bg-21-1323-2024, 2024
Short summary
Short summary
Shellfish aquaculture operates in nearshore areas where data on ocean acidification parameters are limited. We show daily and seasonal variability in pH and saturation states of calcium carbonate at nearshore aquaculture sites in British Columbia, Canada, and determine the contributing drivers of this variability. We find that nearshore locations have greater variability than open waters and that the uptake of carbon by phytoplankton is the major driver of pH and saturation state variability.
S. Alejandra Castillo Cieza, Rachel H. R. Stanley, Pierre Marrec, Diana N. Fontaine, E. Taylor Crockford, Dennis J. McGillicuddy Jr., Arshia Mehta, Susanne Menden-Deuer, Emily E. Peacock, Tatiana A. Rynearson, Zoe O. Sandwith, Weifeng Zhang, and Heidi M. Sosik
Biogeosciences, 21, 1235–1257, https://doi.org/10.5194/bg-21-1235-2024, https://doi.org/10.5194/bg-21-1235-2024, 2024
Short summary
Short summary
The coastal ocean in the northeastern USA provides many services, including fisheries and habitats for threatened species. In summer 2019, a bloom occurred of a large unusual phytoplankton, the diatom Hemiaulus, with nitrogen-fixing symbionts. This led to vast changes in productivity and grazing rates in the ecosystem. This work shows that the emergence of one species can have profound effects on ecosystem function. Such changes may become more prevalent as the ocean warms due to climate change.
Claudine Hauri, Brita Irving, Sam Dupont, Rémi Pagés, Donna D. W. Hauser, and Seth L. Danielson
Biogeosciences, 21, 1135–1159, https://doi.org/10.5194/bg-21-1135-2024, https://doi.org/10.5194/bg-21-1135-2024, 2024
Short summary
Short summary
Arctic marine ecosystems are highly susceptible to impacts of climate change and ocean acidification. We present pH and pCO2 time series (2016–2020) from the Chukchi Ecosystem Observatory and analyze the drivers of the current conditions to get a better understanding of how climate change and ocean acidification could affect the ecological niches of organisms.
William Hiles, Lucy C. Miller, Craig Smeaton, and William E. N. Austin
Biogeosciences, 21, 929–948, https://doi.org/10.5194/bg-21-929-2024, https://doi.org/10.5194/bg-21-929-2024, 2024
Short summary
Short summary
Saltmarsh soils may help to limit the rate of climate change by storing carbon. To understand their impacts, they must be accurately mapped. We use drone data to estimate the size of three saltmarshes in NE Scotland. We find that drone imagery, combined with tidal data, can reliably inform our understanding of saltmarsh size. When compared with previous work using vegetation communities, we find that our most reliable new estimates of stored carbon are 15–20 % smaller than previously estimated.
De'Marcus Robinson, Anh L. D. Pham, David J. Yousavich, Felix Janssen, Frank Wenzhöfer, Eleanor C. Arrington, Kelsey M. Gosselin, Marco Sandoval-Belmar, Matthew Mar, David L. Valentine, Daniele Bianchi, and Tina Treude
Biogeosciences, 21, 773–788, https://doi.org/10.5194/bg-21-773-2024, https://doi.org/10.5194/bg-21-773-2024, 2024
Short summary
Short summary
The present study suggests that high release of ferrous iron from the seafloor of the oxygen-deficient Santa Barabara Basin (California) supports surface primary productivity, creating positive feedback on seafloor iron release by enhancing low-oxygen conditions in the basin.
David J. Yousavich, De'Marcus Robinson, Xuefeng Peng, Sebastian J. E. Krause, Frank Wenzhöfer, Felix Janssen, Na Liu, Jonathan Tarn, Franklin Kinnaman, David L. Valentine, and Tina Treude
Biogeosciences, 21, 789–809, https://doi.org/10.5194/bg-21-789-2024, https://doi.org/10.5194/bg-21-789-2024, 2024
Short summary
Short summary
Declining oxygen (O2) concentrations in coastal oceans can threaten people’s ways of life and food supplies. Here, we investigate how mats of bacteria that proliferate on the seafloor of the Santa Barbara Basin sustain and potentially worsen these O2 depletion events through their unique chemoautotrophic metabolism. Our study shows how changes in seafloor microbiology and geochemistry brought on by declining O2 concentrations can help these mats grow as well as how that growth affects the basin.
Krysten Rutherford, Katja Fennel, Lina Garcia Suarez, and Jasmin G. John
Biogeosciences, 21, 301–314, https://doi.org/10.5194/bg-21-301-2024, https://doi.org/10.5194/bg-21-301-2024, 2024
Short summary
Short summary
We downscaled two mid-century (~2075) ocean model projections to a high-resolution regional ocean model of the northwest North Atlantic (NA) shelf. In one projection, the NA shelf break current practically disappears; in the other it remains almost unchanged. This leads to a wide range of possible future shelf properties. More accurate projections of coastal circulation features would narrow the range of possible outcomes of biogeochemical projections for shelf regions.
Lennart Thomas Bach
Biogeosciences, 21, 261–277, https://doi.org/10.5194/bg-21-261-2024, https://doi.org/10.5194/bg-21-261-2024, 2024
Short summary
Short summary
Ocean alkalinity enhancement (OAE) is a widely considered marine carbon dioxide removal method. OAE aims to accelerate chemical rock weathering, which is a natural process that slowly sequesters atmospheric carbon dioxide. This study shows that the addition of anthropogenic alkalinity via OAE can reduce the natural release of alkalinity and, therefore, reduce the efficiency of OAE for climate mitigation. However, the additionality problem could be mitigated via a variety of activities.
Tsuneo Ono, Daisuke Muraoka, Masahiro Hayashi, Makiko Yorifuji, Akihiro Dazai, Shigeyuki Omoto, Takehiro Tanaka, Tomohiro Okamura, Goh Onitsuka, Kenji Sudo, Masahiko Fujii, Ryuji Hamanoue, and Masahide Wakita
Biogeosciences, 21, 177–199, https://doi.org/10.5194/bg-21-177-2024, https://doi.org/10.5194/bg-21-177-2024, 2024
Short summary
Short summary
We carried out parallel year-round observations of pH and related parameters in five stations around the Japan coast. It was found that short-term acidified situations with Omega_ar less than 1.5 occurred at four of five stations. Most of such short-term acidified events were related to the short-term low salinity event, and the extent of short-term pH drawdown at high freshwater input was positively correlated with the nutrient concentration of the main rivers that flow into the coastal area.
K. Mareike Paul, Martijn Hermans, Sami A. Jokinen, Inda Brinkmann, Helena L. Filipsson, and Tom Jilbert
Biogeosciences, 20, 5003–5028, https://doi.org/10.5194/bg-20-5003-2023, https://doi.org/10.5194/bg-20-5003-2023, 2023
Short summary
Short summary
Seawater naturally contains trace metals such as Mo and U, which accumulate under low oxygen conditions on the seafloor. Previous studies have used sediment Mo and U contents as an archive of changing oxygen concentrations in coastal waters. Here we show that in fjords the use of Mo and U for this purpose may be impaired by additional processes. Our findings have implications for the reliable use of Mo and U to reconstruct oxygen changes in fjords.
Hannah Sharpe, Michel Gosselin, Catherine Lalande, Alexandre Normandeau, Jean-Carlos Montero-Serrano, Khouloud Baccara, Daniel Bourgault, Owen Sherwood, and Audrey Limoges
Biogeosciences, 20, 4981–5001, https://doi.org/10.5194/bg-20-4981-2023, https://doi.org/10.5194/bg-20-4981-2023, 2023
Short summary
Short summary
We studied the impact of submarine canyon processes within the Pointe-des-Monts system on biogenic matter export and phytoplankton assemblages. Using data from three oceanographic moorings, we show that the canyon experienced two low-amplitude sediment remobilization events in 2020–2021 that led to enhanced particle fluxes in the deep-water column layer > 2.6 km offshore. Sinking phytoplankton fluxes were lower near the canyon compared to background values from the lower St. Lawrence Estuary.
Dewi Langlet, Florian Mermillod-Blondin, Noémie Deldicq, Arthur Bauville, Gwendoline Duong, Lara Konecny, Mylène Hugoni, Lionel Denis, and Vincent M. P. Bouchet
Biogeosciences, 20, 4875–4891, https://doi.org/10.5194/bg-20-4875-2023, https://doi.org/10.5194/bg-20-4875-2023, 2023
Short summary
Short summary
Benthic foraminifera are single-cell marine organisms which can move in the sediment column. They were previously reported to horizontally and vertically transport sediment particles, yet the impact of their motion on the dissolved fluxes remains unknown. Using microprofiling, we show here that foraminiferal burrow formation increases the oxygen penetration depth in the sediment, leading to a change in the structure of the prokaryotic community.
Masahiko Fujii, Ryuji Hamanoue, Lawrence Patrick Cases Bernardo, Tsuneo Ono, Akihiro Dazai, Shigeyuki Oomoto, Masahide Wakita, and Takehiro Tanaka
Biogeosciences, 20, 4527–4549, https://doi.org/10.5194/bg-20-4527-2023, https://doi.org/10.5194/bg-20-4527-2023, 2023
Short summary
Short summary
This is the first study of the current and future impacts of climate change on Pacific oyster farming in Japan. Future coastal warming and acidification may affect oyster larvae as a result of longer exposure to lower-pH waters. A prolonged spawning period may harm oyster processing by shortening the shipping period and reducing oyster quality. To minimize impacts on Pacific oyster farming, in addition to mitigation measures, local adaptation measures may be required.
Amanda Y. L. Cheong, Kogila Vani Annammala, Ee Ling Yong, Yongli Zhou, Robert S. Nichols, and Patrick Martin
EGUsphere, https://doi.org/10.5194/egusphere-2023-2528, https://doi.org/10.5194/egusphere-2023-2528, 2023
Short summary
Short summary
We measured nutrients and dissolved organic matter for one year in a eutrophic tropical estuary to understand their sources and cycling. Our data show that the dissolved organic matter originates partly from land and partly from microbial processes in the water. Internal recycling is likely important for maintaining high nutrient concentrations, and we found that there is often excess nitrogen over silicon and phosphorus. Our data help to explain how eutrophication persists in this system.
Marlena Szeligowska, Déborah Benkort, Anna Przyborska, Mateusz Moskalik, Bernabé Moreno, Emilia Trudnowska, and Katarzyna Błachowiak-Samołyk
Biogeosciences Discuss., https://doi.org/10.5194/bg-2023-162, https://doi.org/10.5194/bg-2023-162, 2023
Revised manuscript accepted for BG
Short summary
Short summary
European Arctic experiences rapid regional warming resulting in the retreat of glaciers terminating in the sea onto land. Due to this process, area of one of the well-studied fjords, Hornsund, increased by 100 km2 and 38 %. Using improved mathematical model, we estimated that despite some negative consequences of glacial meltwater release such newly ice-free area markedly contribute to atmospheric carbon uptake and become efficient carbon sinks.
Taketoshi Kodama, Atsushi Nishimoto, Ken-ichi Nakamura, Misato Nakae, Naoki Iguchi, Yosuke Igeta, and Yoichi Kogure
Biogeosciences, 20, 3667–3682, https://doi.org/10.5194/bg-20-3667-2023, https://doi.org/10.5194/bg-20-3667-2023, 2023
Short summary
Short summary
Carbon and nitrogen are essential elements for organisms; their stable isotope ratios (13C : 12C, 15N : 14N) are useful tools for understanding turnover and movement in the ocean. In the Sea of Japan, the environment is rapidly being altered by human activities. The 13C : 12C of small organic particles is increased by active carbon fixation, and phytoplankton growth increases the values. The 15N : 14N variations suggest that nitrates from many sources contribute to organic production.
Aaron Ferderer, Kai G. Schulz, Ulf Riebesell, Kirralee G. Baker, Zanna Chase, and Lennart Thomas Bach
Biogeosciences Discuss., https://doi.org/10.5194/bg-2023-144, https://doi.org/10.5194/bg-2023-144, 2023
Revised manuscript accepted for BG
Short summary
Short summary
Ocean alkalinity enhancement (OAE) is a promising method of atmospheric carbon removal, however it's ecological impacts remain largely unknown. We assessed the effects of simulated silicate and calcium based mineral OAE on diatom silicification. We found that increased silicate concentrations from silicate based OAE increased diatom silicification. In contrast, the enhancement of alkalinity had no effect on community silicification and minimal effects on the silicification of different genera.
Aubin Thibault de Chanvalon, George W. Luther, Emily R. Estes, Jennifer Necker, Bradley M. Tebo, Jianzhong Su, and Wei-Jun Cai
Biogeosciences, 20, 3053–3071, https://doi.org/10.5194/bg-20-3053-2023, https://doi.org/10.5194/bg-20-3053-2023, 2023
Short summary
Short summary
The intensity of the oceanic trap of CO2 released by anthropogenic activities depends on the alkalinity brought by continental weathering. Between ocean and continent, coastal water and estuaries can limit or favour the alkalinity transfer. This study investigate new interactions between dissolved metals and alkalinity in the oxygen-depleted zone of estuaries.
Joonas J. Virtasalo, Peter Österholm, and Eero Asmala
Biogeosciences, 20, 2883–2901, https://doi.org/10.5194/bg-20-2883-2023, https://doi.org/10.5194/bg-20-2883-2023, 2023
Short summary
Short summary
We mixed acidic metal-rich river water from acid sulfate soils and seawater in the laboratory to study the flocculation of dissolved metals and organic matter in estuaries. Al and Fe flocculated already at a salinity of 0–2 to large organic flocs (>80 µm size). Precipitation of Al and Fe hydroxide flocculi (median size 11 µm) began when pH exceeded ca. 5.5. Mn transferred weakly to Mn hydroxides and Co to the flocs. Up to 50 % of Cu was associated with the flocs, irrespective of seawater mixing.
Moritz Baumann, Allanah Joy Paul, Jan Taucher, Lennart Thomas Bach, Silvan Goldenberg, Paul Stange, Fabrizio Minutolo, and Ulf Riebesell
Biogeosciences, 20, 2595–2612, https://doi.org/10.5194/bg-20-2595-2023, https://doi.org/10.5194/bg-20-2595-2023, 2023
Short summary
Short summary
The sinking velocity of marine particles affects how much atmospheric CO2 is stored inside our oceans. We measured particle sinking velocities in the Peruvian upwelling system and assessed their physical and biochemical drivers. We found that sinking velocity was mainly influenced by particle size and porosity, while ballasting minerals played only a minor role. Our findings help us to better understand the particle sinking dynamics in this highly productive marine system.
Kyle E. Hinson, Marjorie A. M. Friedrichs, Raymond G. Najjar, Maria Herrmann, Zihao Bian, Gopal Bhatt, Pierre St-Laurent, Hanqin Tian, and Gary Shenk
Biogeosciences, 20, 1937–1961, https://doi.org/10.5194/bg-20-1937-2023, https://doi.org/10.5194/bg-20-1937-2023, 2023
Short summary
Short summary
Climate impacts are essential for environmental managers to consider when implementing nutrient reduction plans designed to reduce hypoxia. This work highlights relative sources of uncertainty in modeling regional climate impacts on the Chesapeake Bay watershed and consequent declines in bay oxygen levels. The results demonstrate that planned water quality improvement goals are capable of reducing hypoxia levels by half, offsetting climate-driven impacts on terrestrial runoff.
Linquan Mu, Jaime B. Palter, and Hongjie Wang
Biogeosciences, 20, 1963–1977, https://doi.org/10.5194/bg-20-1963-2023, https://doi.org/10.5194/bg-20-1963-2023, 2023
Short summary
Short summary
Enhancing ocean alkalinity accelerates carbon dioxide removal from the atmosphere. We hypothetically added alkalinity to the Amazon River and examined the increment of the carbon uptake by the Amazon plume. We also investigated the minimum alkalinity addition in which this perturbation at the river mouth could be detected above the natural variability.
Karl M. Attard, Anna Lyssenko, and Iván F. Rodil
Biogeosciences, 20, 1713–1724, https://doi.org/10.5194/bg-20-1713-2023, https://doi.org/10.5194/bg-20-1713-2023, 2023
Short summary
Short summary
Aquatic plants produce a large amount of organic matter through photosynthesis that, following erosion, is deposited on the seafloor. In this study, we show that plant detritus can trigger low-oxygen conditions (hypoxia) in shallow coastal waters, making conditions challenging for most marine animals. We propose that the occurrence of hypoxia may be underestimated because measurements typically do not consider the region closest to the seafloor, where detritus accumulates.
M. James McLaughlin, Cindy Bessey, Gary A. Kendrick, John Keesing, and Ylva S. Olsen
Biogeosciences, 20, 1011–1026, https://doi.org/10.5194/bg-20-1011-2023, https://doi.org/10.5194/bg-20-1011-2023, 2023
Short summary
Short summary
Coral reefs face increasing pressures from environmental change at present. The coral reef framework is produced by corals and calcifying algae. The Kimberley region of Western Australia has escaped land-based anthropogenic impacts. Specimens of the dominant coral and algae were collected from Browse Island's reef platform and incubated in mesocosms to measure calcification and production patterns of oxygen. This study provides important data on reef building and climate-driven effects.
Patricia Ayón Dejo, Elda Luz Pinedo Arteaga, Anna Schukat, Jan Taucher, Rainer Kiko, Helena Hauss, Sabrina Dorschner, Wilhelm Hagen, Mariona Segura-Noguera, and Silke Lischka
Biogeosciences, 20, 945–969, https://doi.org/10.5194/bg-20-945-2023, https://doi.org/10.5194/bg-20-945-2023, 2023
Short summary
Short summary
Ocean upwelling regions are highly productive. With ocean warming, severe changes in upwelling frequency and/or intensity and expansion of accompanying oxygen minimum zones are projected. In a field experiment off Peru, we investigated how different upwelling intensities affect the pelagic food web and found failed reproduction of dominant zooplankton. The changes projected could severely impact the reproductive success of zooplankton communities and the pelagic food web in upwelling regions.
Mathilde Jutras, Alfonso Mucci, Gwenaëlle Chaillou, William A. Nesbitt, and Douglas W. R. Wallace
Biogeosciences, 20, 839–849, https://doi.org/10.5194/bg-20-839-2023, https://doi.org/10.5194/bg-20-839-2023, 2023
Short summary
Short summary
The deep waters of the lower St Lawrence Estuary and gulf have, in the last decades, experienced a strong decline in their oxygen concentration. Below 65 µmol L-1, the waters are said to be hypoxic, with dire consequences for marine life. We show that the extent of the hypoxic zone shows a seven-fold increase in the last 20 years, reaching 9400 km2 in 2021. After a stable period at ~ 65 µmol L⁻¹ from 1984 to 2019, the oxygen level also suddenly decreased to ~ 35 µmol L-1 in 2020.
Sachi Umezawa, Manami Tozawa, Yuichi Nosaka, Daiki Nomura, Hiroji Onishi, Hiroto Abe, Tetsuya Takatsu, and Atsushi Ooki
Biogeosciences, 20, 421–438, https://doi.org/10.5194/bg-20-421-2023, https://doi.org/10.5194/bg-20-421-2023, 2023
Short summary
Short summary
We conducted repetitive observations in Funka Bay, Japan, during the spring bloom 2019. We found nutrient concentration decreases in the dark subsurface layer during the bloom. Incubation experiments confirmed that diatoms could consume nutrients at a substantial rate, even in darkness. We concluded that the nutrient reduction was mainly caused by nutrient consumption by diatoms in the dark.
Dirk Jong, Lisa Bröder, Tommaso Tesi, Kirsi H. Keskitalo, Nikita Zimov, Anna Davydova, Philip Pika, Negar Haghipour, Timothy I. Eglinton, and Jorien E. Vonk
Biogeosciences, 20, 271–294, https://doi.org/10.5194/bg-20-271-2023, https://doi.org/10.5194/bg-20-271-2023, 2023
Short summary
Short summary
With this study, we want to highlight the importance of studying both land and ocean together, and water and sediment together, as these systems function as a continuum, and determine how organic carbon derived from permafrost is broken down and its effect on global warming. Although on the one hand it appears that organic carbon is removed from sediments along the pathway of transport from river to ocean, it also appears to remain relatively ‘fresh’, despite this removal and its very old age.
Georgia Filippi, Manos Dassenakis, Vasiliki Paraskevopoulou, and Konstantinos Lazogiannis
Biogeosciences, 20, 163–189, https://doi.org/10.5194/bg-20-163-2023, https://doi.org/10.5194/bg-20-163-2023, 2023
Short summary
Short summary
The pollution of the western Saronikos Gulf from heavy metals has been examined through the study of marine sediment cores. It is a deep gulf (maximum depth 440 m) near Athens affected by industrial and volcanic activity. Eight cores were received from various stations and depths and analysed for their heavy metal content and geochemical characteristics. The results were evaluated by using statistical methods, environmental indicators and comparisons with old data.
Jing He and Michael D. Tyka
Biogeosciences, 20, 27–43, https://doi.org/10.5194/bg-20-27-2023, https://doi.org/10.5194/bg-20-27-2023, 2023
Short summary
Short summary
Recently, ocean alkalinity enhancement (OAE) has gained interest as a scalable way to address the urgent need for negative CO2 emissions. In this paper we examine the capacity of different coastlines to tolerate alkalinity enhancement and the time scale of CO2 uptake following the addition of a given quantity of alkalinity. The results suggest that OAE has significant potential and identify specific favorable and unfavorable coastlines for its deployment.
Arnaud Laurent, Haiyan Zhang, and Katja Fennel
Biogeosciences, 19, 5893–5910, https://doi.org/10.5194/bg-19-5893-2022, https://doi.org/10.5194/bg-19-5893-2022, 2022
Short summary
Short summary
The Changjiang is the main terrestrial source of nutrients to the East China Sea (ECS). Nutrient delivery to the ECS has been increasing since the 1960s, resulting in low oxygen (hypoxia) during phytoplankton decomposition in summer. River phosphorus (P) has increased less than nitrogen, and therefore, despite the large nutrient delivery, phytoplankton growth can be limited by the lack of P. Here, we investigate this link between P limitation, phytoplankton production/decomposition, and hypoxia.
Coline Poppeschi, Guillaume Charria, Anne Daniel, Romaric Verney, Peggy Rimmelin-Maury, Michaël Retho, Eric Goberville, Emilie Grossteffan, and Martin Plus
Biogeosciences, 19, 5667–5687, https://doi.org/10.5194/bg-19-5667-2022, https://doi.org/10.5194/bg-19-5667-2022, 2022
Short summary
Short summary
This paper aims to understand interannual changes in the initiation of the phytoplankton growing period (IPGP) in the current context of global climate changes over the last 20 years. An important variability in the timing of the IPGP is observed with a trend towards a later IPGP during this last decade. The role and the impact of extreme events (cold spells, floods, and wind burst) on the IPGP is also detailed.
Lin Yang, Jing Zhang, Anja Engel, and Gui-Peng Yang
Biogeosciences, 19, 5251–5268, https://doi.org/10.5194/bg-19-5251-2022, https://doi.org/10.5194/bg-19-5251-2022, 2022
Short summary
Short summary
Enrichment factors of dissolved organic matter (DOM) in the eastern marginal seas of China exhibited a significant spatio-temporal variation. Photochemical and enrichment processes co-regulated DOM enrichment in the sea-surface microlayer (SML). Autochthonous DOM was more frequently enriched in the SML than terrestrial DOM. DOM in the sub-surface water exhibited higher aromaticity than that in the SML.
Mona Norbisrath, Johannes Pätsch, Kirstin Dähnke, Tina Sanders, Gesa Schulz, Justus E. E. van Beusekom, and Helmuth Thomas
Biogeosciences, 19, 5151–5165, https://doi.org/10.5194/bg-19-5151-2022, https://doi.org/10.5194/bg-19-5151-2022, 2022
Short summary
Short summary
Total alkalinity (TA) regulates the oceanic storage capacity of atmospheric CO2. TA is also metabolically generated in estuaries and influences coastal carbon storage through its inflows. We used water samples and identified the Hamburg port area as the one with highest TA generation. Of the overall riverine TA load, 14 % is generated within the estuary. Using a biogeochemical model, we estimated potential effects on the coastal carbon storage under possible anthropogenic and climate changes.
Le Zhang and Z. George Xue
Biogeosciences, 19, 4589–4618, https://doi.org/10.5194/bg-19-4589-2022, https://doi.org/10.5194/bg-19-4589-2022, 2022
Short summary
Short summary
We adopt a high-resolution carbon model for the Gulf of Mexico (GoM) and calculate the decadal trends of important carbon system variables in the GoM from 2001 to 2019. The GoM surface CO2 values experienced a steady increase over the past 2 decades, and the ocean surface pH is declining. Although carbonate saturation rates remain supersaturated with aragonite, they show a slightly decreasing trend. The northern GoM is a stronger carbon sink than we thought.
Michael M. Whitney
Biogeosciences, 19, 4479–4497, https://doi.org/10.5194/bg-19-4479-2022, https://doi.org/10.5194/bg-19-4479-2022, 2022
Short summary
Short summary
Coastal hypoxia is a major environmental problem of increasing severity. The 21st-century projections analyzed indicate global coastal waters will warm and experience rapid declines in oxygen. The forecasted median coastal trends for increasing sea surface temperature and decreasing oxygen capacity are 48 % and 18 % faster than the rates observed over the last 4 decades. Existing hypoxic areas are expected to worsen, and new hypoxic areas likely will emerge under these warming-related pressures.
Bryce Van Dam, Nele Lehmann, Mary A. Zeller, Andreas Neumann, Daniel Pröfrock, Marko Lipka, Helmuth Thomas, and Michael Ernst Böttcher
Biogeosciences, 19, 3775–3789, https://doi.org/10.5194/bg-19-3775-2022, https://doi.org/10.5194/bg-19-3775-2022, 2022
Short summary
Short summary
We quantified sediment–water exchange at shallow sites in the North and Baltic seas. We found that porewater irrigation rates in the former were approximately twice as high as previously estimated, likely driven by relatively high bioirrigative activity. In contrast, we found small net fluxes of alkalinity, ranging from −35 µmol m−2 h−1 (uptake) to 53 µmol m−2 h−1 (release). We attribute this to low net denitrification, carbonate mineral (re-)precipitation, and sulfide (re-)oxidation.
Jiaying Abby Guo, Robert Strzepek, Anusuya Willis, Aaron Ferderer, and Lennart Thomas Bach
Biogeosciences, 19, 3683–3697, https://doi.org/10.5194/bg-19-3683-2022, https://doi.org/10.5194/bg-19-3683-2022, 2022
Short summary
Short summary
Ocean alkalinity enhancement is a CO2 removal method with significant potential, but it can lead to a perturbation of the ocean with trace metals such as nickel. This study tested the effect of increasing nickel concentrations on phytoplankton growth and photosynthesis. We found that the response to nickel varied across the 11 phytoplankton species tested here, but the majority were rather insensitive. We note, however, that responses may be different under other experimental conditions.
Malcolm E. Scully, W. Rockwell Geyer, David Borkman, Tracy L. Pugh, Amy Costa, and Owen C. Nichols
Biogeosciences, 19, 3523–3536, https://doi.org/10.5194/bg-19-3523-2022, https://doi.org/10.5194/bg-19-3523-2022, 2022
Short summary
Short summary
For two consecutive summers, the bottom waters in southern Cape Cod Bay became severely depleted of dissolved oxygen. Low oxygen levels in bottom waters have never been reported in this area before, and this unprecedented occurrence is likely the result of a new algae species that recently began blooming during the late-summer months. We present data suggesting that blooms of this new species are the result of regional climate change including warmer waters and changes in summer winds.
Zheng Chen, Bin Wang, Chuang Xu, Zhongren Zhang, Shiyu Li, and Jiatang Hu
Biogeosciences, 19, 3469–3490, https://doi.org/10.5194/bg-19-3469-2022, https://doi.org/10.5194/bg-19-3469-2022, 2022
Short summary
Short summary
Deterioration of low-oxygen conditions in the coastal waters off Hong Kong was revealed by monitoring data over two decades. The declining wind forcing and the increasing nutrient input contributed significantly to the areal expansion and intense deterioration of low-oxygen conditions. Also, the exacerbated eutrophication drove a shift in the dominant source of organic matter from terrestrial inputs to in situ primary production, which has probably led to an earlier onset of hypoxia in summer.
Cited articles
Alber, M., Swenson, E. M., Adamowicz, S. C., and Mendelssohn, I. A.: Salt Marsh Dieback:
An overview of recent events in the US, Estuar. Coast. Shelf Sci., 80, 1–11,
https://doi.org/10.1016/j.ecss.2008.08.009, 2008.
Alongi, D. M.: The Impact of Climate Change on Mangrove Forests, Curr. Clim. Change
Rep., 1, 30–39, https://doi.org/10.1007/s40641-015-0002-x, 2015.
Asbridge, E., Lucas, R., Ticehurst, C., and Bunting, P.: Mangrove response to
environmental change in Australia's Gulf of Carpentaria, Ecol. Evol., 6, 3523–3539, 2016.
Asbridge, E., Bartolo, R., Finlayson, C. M., Lucas, R. M., Rogers, K., and Woodroffe,
C. D.: Assessing the distribution and drivers of mangrove dieback in Kakadu National Park,
northern Australia, Estuar. Coast. Shelf Sci., 228, 106353, https://doi.org/10.1016/j.ecss.2019.106353,
2019.
Barbier, E. B., Hacker, S. D., Kennedy, C., Koch, E. W., Stier, A. C., and Silliman,
B. R.: The value of estuarine and coastal ecosystem services, Ecol. Monogr., 81, 169–193,
https://doi.org/10.1890/10-1510.1, 2011.
Bronk Ramsey, C.: Deposition models for chronological records, Quat. Sci. Rev., 27,
42–60, 2008.
Brookhouse, M.: Eucalypt dendrochronology: past, present and potential, Aust. J. Bot.,
54, 435–449, 2006.
Burdige, D. J.: Estuarine and coastal sediments – coupled biogeochemical cycling,
Treat. Estuar. Coast. Sci., 5, 279–316, 2011.
Bureau of Meteorology: Climate data online, available at: http://www.bom.gov.au/climate/data/, last access: 12 August 2019.
Burton, E. D., Bush, R. T., and Sullivan, L. A.: Sedimentary iron geochemistry in
acidic waterways associated with coastal lowland acid sulfate soils, Geochim. Cosmochim. Acta, 70,
5455–5468, https://doi.org/10.1016/j.gca.2006.08.016, 2006.
Burton, E. D., Sullivan, L. A., Bush, R. T., Johnston, S. G., and Keene, A. F.: A
simple and inexpensive chromium-reducible sulfur method for acid-sulfate soils, Appl. Geochem.,
23, 2759–2766, 2008.
Cai, W., Borlace, S., Lengaigne, M., van Rensch, P., Collins, M., Vecchi, G.,
Timmermann, A., Santoso, A., McPhaden, M. J., Wu, L., England, M. H., Wang, G., Guilyardi E., and
Jin, F. F.: Increasing frequency of extreme El Niño events due to greenhouse warming,
Nat. Clim. Change, 4, 111, https://doi.org/10.1038/nclimate2100, 2014.
Cook, E. R. and Jacoby, G. C.: Tree-ring-drought relationships in the Hudson Valley, New York, Science, 198, 399–401, 1977.
Donato, D. Kauffman, C., Murdiyarso, J. B., Kurnianto, D., Stidham S. M., and Kanninen,
M.: Mangroves among the most carbon-rich forests in the tropics, Nat. Geosci., 4, 293–297, 2011.
Elrod, V. A., Berelson, W. M., Coale K. H., and Johnson, K. S.: The flux of iron from
continental shelf sediments: A missing source for global budgets, Geophys. Res. Lett., 31, L12307,
https://doi.org/10.1029/2004gl020216, 2004.
Fabricius, A.-L., Duester, L., Ecker, D., and Ternes, T. A.: New Microprofiling and
Micro Sampling System for Water Saturated Environmental Boundary Layers, Environ. Sci. Technol.,
48, 8053–8061, 2014.
Farquhar, G., K. Hubick, Condon, A., and Richards, R.: Carbon isotope fractionation and
plant water-use efficiency, Stable isotopes in ecological research, Springer, New York, 21–40, 1989.
Farquhar, G. and Richards, R.: Isotopic composition of plant carbon correlates with
water-use efficiency of wheat genotypes, Funct. Plant Biol., 11, 539–552, 1984.
Fink, D., Hotchkis, M., Hua, Q., Jacobsen, G., Smith, A. M., Zoppi, U., Child, D.,
Mifsud, C., van der Gaast, H., and Williams, A.: The antares AMS facility at ANSTO,
Nucl. Instrum. Methods Phys. Res. B, 223, 109–115, 2004.
Freund, M. B., Henley, B. J., Karoly, D. J., McGregor, H. V., Abram, N. J., and
Dommenget, D.: Higher frequency of Central Pacific El Niño events in recent decades relative
to past centuries, Nat. Geosci., 12, 450–455, https://doi.org/10.1038/s41561-019-0353-3, 2019.
Fung, I. Y., Meyn, S. K., Tegen, I., Doney, S. C., John, J. G., and Bishop, J. K.: Iron
supply and demand in the upper ocean, Global Biogeochem. Cy., 14, 281–295, 2000.
Gilman, E. L., Ellison, J., Duke, N. C., and Field, C.: Threats to mangroves from
climate change and adaptation options: A review, Aquat. Bot., 89, 237–250, 2008.
Google Earth: Karumba, Qld, Australia, Digital Globe, 2019.
Gregory, B. R. B., Patterson, R. T., Reinhardt, E. G., Galloway, J. M., and Roe, H. M.:
An evaluation of methodologies for calibrating Itrax X-ray fluorescence counts with ICP-MS
concentration data for discrete sediment samples, Chem. Geol., 521, 12–27, 2019.
Hamilton, S. E. and Casey, D.: Creation of a high spatio-temporal resolution global
database of continuous mangrove forest cover for the 21st century (CGMFC-21), Global
Ecol. Biogeogr., 25, 729–738, 2016.
Harada, Y., Connolly, R. M., Fry, B., Maher, D. T., Sippo, J. Z., Jeffrey, L. C., Bourke, A. J., and Lee, S. Y.: Stable isotopes track the ecological and biogeochemical legacy of mass mangrove forest dieback in the Gulf of Carpentaria, Australia, Biogeosciences Discuss., https://doi.org/https://doi.org/10.5194/bg-2019-468, in review, 2020.
Harris, R. M. B., Beaumont, L. J., Vance, T. R., Tozer, C. R., Remenyi, T. A.,
Perkins-Kirkpatrick, S. E., Mitchell, P. J., Nicotra, A. B., McGregor, S., Andrew, N. R., Letnic,
M., Kearney, M. R., Wernberg, T., Hutley, L. B., Chambers, L. E., Fletcher, M. S., Keatley, M. R.,
Woodward, C. A., Williamson, G., Duke N. C., and Bowman, D. M. J. S.: Biological responses to the
press and pulse of climate trends and extreme events, Nat. Clim. Change, 8, 579–587,
https://doi.org/10.1038/s41558-018-0187-9, 2018.
Harris, T., Hope, P., Oliver, E., Smalley, R., Arblaster, J., Holbrook, N., Duke, N., Pearce, K., Braganza, K., and Bindoff, N.: Climate drivers of the 2015 Gulf of Carpentaria mangrove dieback. Earth Systems and Climate
Change Hub Report No. 2, NESP Earth Systems and Climate Change Hub, Australia, 2017.
Hevia, A., R. Sánchez-Salguero, J. J., Camarero, A., Buras, G.,
Sangüesa-Barreda, J., Galván, D., and Gutiérrez, E.: Towards a better understanding of
long-term wood-chemistry variations in old-growth forests: A case study on ancient Pinus uncinata
trees from the Pyrenees, Sci. Total Environ., 625, 220–232, 2018.
Holloway, C. J., Santos, I. R., and Rose, A. L.: Porewater inputs drive Fe redox
cycling in the water column of a temperate mangrove wetland, Estuar. Coast. Shelf Sci., 207,
259–268, 2018.
Holloway, C. J., Santos, I. R., Tait, D. R., Sanders, C. J., Rose, A. L., Schnetger,
B., Brumsack, H.-J., Macklin, P. A., Sippo, J. Z., and Maher, D. T.: Manganese and iron release
from mangrove porewaters: a significant component of oceanic budgets?, Mar. Chem., 184, 43–52,
2016.
Hoppe-Speer, S. C. L., Adams, J. B., and Rajkaran, A.: Response of mangroves to drought
and non-tidal conditions in St Lucia Estuary, South Africa, Afr. J. Aquat. Sci., 38, 153–162,
https://doi.org/10.2989/16085914.2012.759095, 2013.
Hua, Q. and Barbetti, M.: Review of tropospheric bomb 14C data for carbon
cycle modeling and age calibration purposes, Radiocarbon, 46, 1273–1298, 2004.
Hua, Q., Jacobsen, G. E., Zoppi, U., Lawson, E. M., Williams, A. A., Smith, A. M., and
McGann, M. J.: Progress in radiocarbon target preparation at the ANTARES AMS Centre, Radiocarbon,
43, 275–282, 2001.
Hua, Q., Barbetti, M., Zoppi, U., Fink, D., Watanasak, M., and Jacobsen, G. E.:
Radiocarbon in tropical tree rings during the Little Ice Age, Nucl. Instrum. Methods Phys. Res. B,
223, 489–494, 2004.
Hua, Q., Barbetti, M., and Rakowski, A. Z.: Atmospheric radiocarbon for the period
1950-2010, Radiocarbon, 55, 2059–2072, 2013.
Hunt, J. E., Croudace, I. W., and MacLachlan, S. E.: Use of calibrated ITRAX XRF data
in determining turbidite geochemistry and provenance in Agadir Basin, Northwest African passive
margin, Micro-XRF Studies of Sediment Cores, Springer, Dordrecht, 127–146, 2015.
Jickells, T. and Spokes, L.: The biogeochemistry of iron in seawater, edited by:
Turner, D. R., Hunter, K. A., Wiley, Chichester, UK, 2002.
Johnston, S. G., Keene, A. F., Bush, R. T., Burton, E. D., Sullivan, L. A., Isaacson,
L., McElnea, A. E., Ahern, C. R., Smith, C. D., and Powell B.: Iron geochemical zonation in a
tidally inundated acid sulfate soil wetland, Chem. Geol., 280, 257–270,
https://doi.org/10.1016/j.chemgeo.2010.11.014, 2011.
Johnston, S. G., Morgan, B., and Burton, E. D.: Legacy impacts of acid sulfate soil
runoff on mangrove sediments: Reactive iron accumulation, altered sulfur cycling and trace metal
enrichment, Chem. Geol., 427, 43–53, 2016.
Jones, D. A., Wang, W., and Fawcett, R.: High-quality spatial climate data-sets for
Australia, Austral. Meteorol. Oceanogr. J., 58, 233–248, 2009.
Keene, A. F., Johnston, S. G., Bush, R. T., Burton, E. D., Sullivan, L. A., Dundon, M.,
McElnea, A. E., Smith, C. D., Ahern, C. R., and Powell, B.: Enrichment and heterogeneity of trace
elements at the redox-interface of Fe-rich intertidal sediments, Chem. Geol., 383, 1–12,
https://doi.org/10.1016/j.chemgeo.2014.06.003, 2014.
Kristensen, E., Bouillon, S., Dittmar, T., and Marchand, C.: Organic carbon dynamics in
mangrove ecosystems: A review, Aquat. Bot., 89, 201–219, 2008.
Lee, T. and McPhaden, M. J.: Increasing intensity of El Niño in the
central-equatorial Pacific, Geophys. Res. Lett., 37, L14603, https://doi.org/10.1029/2010GL044007, 2010.
Lovelock, C. E., Cahoon, D. R., Friess, D. A., Guntenspergen, G. R., Krauss, K. W.,
Reef, R., Rogers, K., Saunders, M. L., Sidik, F., and Swales, A.: The vulnerability of
Indo-Pacific mangrove forests to sea-level rise, Nature, 526, 559–563, 2015.
Lovelock, C. E., Feller, I. C., Reef, R., Hickey, S., and Ball, M. C.: Mangrove dieback
during fluctuating sea levels, Sci. Rep., 7, 1680, https://doi.org/10.1038/s41598-017-01927-6, 2017.
Marchand, C., Fernandez, J. M., and Moreton, B.: Trace metal geochemistry in mangrove
sediments and their transfer to mangrove plants (New Caledonia), Sci. Total Environ., 562,
216–227, 2016.
Maxwell, J. T., Harley, G. L., and Rahman, A. F.: Annual Growth Rings in Two Mangrove
Species from the Sundarbans, Bangladesh Demonstrate Linkages to Sea-Level Rise and Broad-Scale
Ocean-Atmosphere Variability, Wetlands, 38, 1159–1170, https://doi.org/10.1007/s13157-018-1079-5, 2018.
McKee, K. L., Mendelssohn, I. A., and Materne, M. D.: Acute salt marsh dieback in the
Mississippi River deltaic plain: a drought-induced phenomenon?, Global Ecol. Biogeogr., 13,
65–73, https://doi.org/10.1111/j.1466-882X.2004.00075.x, 2004.
Medina, E. and Francisco, M.: Osmolality and 13C of leaf tissues of mangrove
species from environments of contrasting rainfall and salinity, Estuar. Coast. Shelf Sci., 45,
337–344, 1997.
Nguyen, H. T., Meir, P., Sack, L., Evans, J. R., Oliveira, R. S., and Ball, M. C.: Leaf
water storage increases with salinity and aridity in the mangrove Avicennia marina: integration of
leaf structure, osmotic adjustment and access to multiple water sources, Plant Cell Environ., 40,
1576–1591, 2017.
Nielsen, O. I., Kristensen, E., and Macintosh, D. J.: Impact of fiddler crabs (Uca
spp.) on rates and pathways of benthic mineralization in deposited mangrove shrimp pond waste,
J. Exp. Mar. Biol. Ecol., 289, 59–81, 2003.
Ogburn, M. B. and Alber, M.: An investigation of salt marsh dieback in Georgia using
field transplants, Estuar. Coasts, 29, 54–62, https://doi.org/10.1007/bf02784698, 2006.
Queensland Government: QldGlobe, available at:
https://qldglobe.information.qld.gov.au, last access: August 2019.
Richards, D. R. and Friess, D. A.: Rates and drivers of mangrove deforestation in
Southeast Asia, 2000–2012, P. Natl. Acad. Sci. USA, 113, 344–349, https://doi.org/10.1073/pnas.1510272113,
2016.
Robert, E. M., Schmitz, N., Okello, J. A., Boeren, I., Beeckman, H., and Koedam, N.:
Mangrove growth rings: fact or fiction?, Trees, 25, 49–58, 2011.
Santini, N. S., Hua, Q., Schmitz, N., and Lovelock, C. E.: Radiocarbon dating and wood
density chronologies of mangrove trees in arid Western Australia, PloS one, 8, e80116,
https://doi.org/10.1371/journal.pone.0080116, 2013.
Santini, N. S., Schmitz, N., and Lovelock, C. E.: Variation in wood density and anatomy
in a widespread mangrove species, Trees, 26, 1555–1563, 2012.
Schmitz, N., Verheyden, A., Beeckman, H., Kairo, J. G., and Koedam, N.: Influence of a
salinity gradient on the vessel characters of the mangrove species Rhizophora mucronata,
Ann. Bot., 98, 1321–1330, 2006.
Silliman, B. R., Van De Koppel, J., Bertness, M. D., Stanton, L. E., and Mendelssohn,
I. A.: Drought, snails, and large-scale die-off of southern US salt marshes, Science, 310,
1803–1806, 2005.
Sippo, J. Z., Lovelock, C. E., Santos, I. R., Sanders, C. J., and Maher, D. T.:
Mangrove mortality in a changing climate: An overview, Estuar. Coast. Shelf Sci., 215, 241–249,
https://doi.org/10.1016/j.ecss.2018.10.011, 2018.
Sippo, J. Z., Maher, D. T., Schulz, K. G., Sanders, C. J., McMahon, A., Tucker, J., and
Santos, I. R.: Carbon outwelling across the shelf following a massive mangrove dieback in
Australia: Insights from radium isotopes, Geochim. Cosmochim. Acta, 253, 142–158,
https://doi.org/10.1016/j.gca.2019.03.003, 2019.
Sippo, J. Z., Sanders, C. J., Santos, I. R., Jeffrey, L. C., Call, M., Harada, Y.,
Maguire, K., Brown, D., Conrad, S. R., and Maher, D. T.: Coastal carbon cycle changes following
mangrove loss, Limnol. Oceanogr., https://doi.org/10.1002/lno.11476,
2020.
Stieglitz, T.: Submarine groundwater discharge into the near-shore zone of the Great Barrier Reef, Australia, Mar. Pollut. Bull., 51, 51–59, https://doi.org/10.1016/j.marpolbul.2004.10.055, 2005.
Stuiver, M. and Polach, H. A.: Discussion: reporting of 14C data, Radiocarbon, 19, 355–363, https://doi.org/10.1017/S0033822200003672, 1977.
Turner, J. N., Holmes, N., Davis, S. R., Leng, M. J., Langdon, C., and Scaife, R. G.: A
multiproxy (micro-XRF, pollen, chironomid and stable isotope) lake sediment record for the
Lateglacial to Holocene transition from Thomastown Bog, Ireland, J. Quatern. Sci., 30, 514–528,
2015.
Van Breemen, N.: Redox Processes of Iron and Sulfur Involved in the Formation of Acid
Sulfate Soils, in: Iron in Soils and Clay Minerals, edited by: Stucki, J. W., Goodman, B. A.,
Schwertmann, U., Dordrecht, Springer Netherlands, pp. 825–841, 1988.
Van Der Sleen, P., Groenendijk, P., Vlam, M., Anten, N. P., Boom, A., Bongers, F.,
Pons, T. L., Terburg, G., and Zuidema, P. A.: No growth stimulation of tropical trees by 150 years
of CO2 fertilization but water-use efficiency increased, Nat. Geosci., 8, 24–28,
https://doi.org/10.1038/ngeo2313, 2015.
Verheyden, A., De Ridder, F., Schmitz, N., Beeckman, H., and Koedam, N.:
High-resolution time series of vessel density in Kenyan mangrove trees reveal a link with climate,
New Phytol., 167, 425–435, 2005.
Widlansky, M. J., Timmermann, A., and Cai, W.: Future extreme sea level seesaws in the
tropical Pacific, Sci. Adv., 1, e1500560, https://doi.org/10.1126/sciadv.1500560, 2015.
Witt, B., English, N. B., Balanzategui, D., Hua, Q., Gadd, P., Heijnis, H., and Bird, M. I.: The climate reconstruction potential of Acacia cambagei (gidgee) for semi-arid regions of Australia using stable isotopes and elemental abundances, J. Arid Environ., 136, 19–27, https://doi.org/10.1016/j.jaridenv.2016.10.002, 2017.
Zhu, Q. and Aller, R. C.: Two-dimensional dissolved ferrous iron distributions in
marine sediments as revealed by a novel planar optical sensor, Mar. Chem., 136, 14–23, 2012.
Zhu, Q., Aller, R. C., and Fan, Y.: Two-dimensional pH distributions and dynamics in
bioturbated marine sediments, Geochim. Cosmochim. Acta, 70, 4933–4949, 2006.
Short summary
In 2015–2016, a massive mangrove dieback event occurred along ~1000 km of coastline in Australia. Multiple lines of evidence from climate data, wood and sediment samples suggest low water availability within the dead mangrove forest. Wood and sediments also reveal a large increase in iron concentrations in mangrove sediments during the dieback. This study supports the hypothesis that the forest dieback was associated with low water availability driven by a climate-change-related ENSO event.
In 2015–2016, a massive mangrove dieback event occurred along ~1000 km of coastline in ...
Altmetrics
Final-revised paper
Preprint