Articles | Volume 17, issue 20
https://doi.org/10.5194/bg-17-5209-2020
© 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-17-5209-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
29 Oct 2020
Research article |
| 29 Oct 2020
| 29 Oct 2020
Methane paradox in tropical lakes? Sedimentary fluxes rather than pelagic production in oxic conditions sustain methanotrophy and emissions to the atmosphere
Cédric Morana
CORRESPONDING AUTHOR
KU Leuven, Leuven, Belgium
Université de Liège, Liège, Belgium
Steven Bouillon
KU Leuven, Leuven, Belgium
Vimac Nolla-Ardèvol
KU Leuven, Leuven, Belgium
Fleur A. E. Roland
Université de Liège, Liège, Belgium
William Okello
National Fisheries Resources Research Institute, Jinja, Uganda
Jean-Pierre Descy
Université de Liège, Liège, Belgium
Angela Nankabirwa
National Fisheries Resources Research Institute, Jinja, Uganda
Erina Nabafu
National Fisheries Resources Research Institute, Jinja, Uganda
Dirk Springael
KU Leuven, Leuven, Belgium
Alberto V. Borges
Université de Liège, Liège, Belgium
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Thomas Bauduin, Nathalie Gypens, and Alberto V. Borges
Biogeosciences, 22, 3785–3805, https://doi.org/10.5194/bg-22-3785-2025, https://doi.org/10.5194/bg-22-3785-2025, 2025
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To investigate if greenhouse gases (GHG) emissions from ponds vary among clear-water ponds with macrophytes and turbid-water ponds with phytoplankton, we measured CO2, CH4, and N2O concentrations and emissions in two clear- and two turbid-water urban ponds in the city of Brussels from June 2021 to December 2023. Differences in CH4 ebullitive emissions were observed between clear- and turbid-water ponds but none for CO2 and N2O emissions.
Mona Huyzentruyt, Maarten Wens, Gregory Scott Fivash, David C. Walters, Steven Bouillon, Joell A. Carr, Glenn C. Guntenspergen, Matthew L. Kirwan, and Stijn Temmerman
EGUsphere, https://doi.org/10.5194/egusphere-2025-3293, https://doi.org/10.5194/egusphere-2025-3293, 2025
This preprint is open for discussion and under review for Biogeosciences (BG).
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Vegetated environments from forests to peatlands store carbon in the soil, which mitigates climate change. But which environment does this best? In this study, we show how the levees of tidal marshes are one of the most effective carbon sequestering environments in the world. This is because soil water-logging and high salinity inhibits carbon degradation while the levee fosters fast vegetation growth, complimented also by the preferential settlement of carbon-rich sediments on the marsh levee.
Zita Kelemen, David P. Gillikin, and Steven Bouillon
Biogeosciences, 22, 2621–2635, https://doi.org/10.5194/bg-22-2621-2025, https://doi.org/10.5194/bg-22-2621-2025, 2025
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We analysed the C and O stable isotope composition (δ13C, δ18O) across the growth axis of museum-archived and recent Chambardia wissmanni shells from the Oubangui River (Congo basin) covering sections of the past ~120 years. Recent shells showed a much wider range of δ18O values compared to historical specimens, consistent with the suggestion that dry periods in the upper Congo basin have become more extreme in recent times and highlighting the potential of this species to reconstruct hydroclimatic conditions.
Vao Fenotiana Razanamahandry, Alberto Vieira Borges, Liesa Brosens, Cedric Morana, Tantely Razafimbelo, Tovonarivo Rafolisy, Gerard Govers, and Steven Bouillon
Biogeosciences, 22, 2403–2424, https://doi.org/10.5194/bg-22-2403-2025, https://doi.org/10.5194/bg-22-2403-2025, 2025
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A comprehensive survey of the biogeochemistry of the Lake Alaotra system showed that the lake and surrounding wetlands acted as a substantial source of new organic carbon (OC), which was exported downstream. Marsh vegetation was the main source of dissolved OC, while phytoplankton contributed to the particulate OC pool. The biogeochemical functioning of Lake Alaotra differs from most East African lakes studied, likely due to its large surface area, shallow water depth, and surrounding wetlands.
Christian Lønborg, Cátia Carreira, Gwenaël Abril, Susana Agustí, Valentina Amaral, Agneta Andersson, Javier Arístegui, Punyasloke Bhadury, Mariana B. Bif, Alberto V. Borges, Steven Bouillon, Maria Ll. Calleja, Luiz C. Cotovicz Jr., Stefano Cozzi, Maryló Doval, Carlos M. Duarte, Bradley Eyre, Cédric G. Fichot, E. Elena García-Martín, Alexandra Garzon-Garcia, Michele Giani, Rafael Gonçalves-Araujo, Renee Gruber, Dennis A. Hansell, Fuminori Hashihama, Ding He, Johnna M. Holding, William R. Hunter, J. Severino P. Ibánhez, Valeria Ibello, Shan Jiang, Guebuem Kim, Katja Klun, Piotr Kowalczuk, Atsushi Kubo, Choon-Weng Lee, Cláudia B. Lopes, Federica Maggioni, Paolo Magni, Celia Marrase, Patrick Martin, S. Leigh McCallister, Roisin McCallum, Patricia M. Medeiros, Xosé Anxelu G. Morán, Frank E. Muller-Karger, Allison Myers-Pigg, Marit Norli, Joanne M. Oakes, Helena Osterholz, Hyekyung Park, Maria Lund Paulsen, Judith A. Rosentreter, Jeff D. Ross, Digna Rueda-Roa, Chiara Santinelli, Yuan Shen, Eva Teira, Tinkara Tinta, Guenther Uher, Masahide Wakita, Nicholas Ward, Kenta Watanabe, Yu Xin, Youhei Yamashita, Liyang Yang, Jacob Yeo, Huamao Yuan, Qiang Zheng, and Xosé Antón Álvarez-Salgado
Earth Syst. Sci. Data, 16, 1107–1119, https://doi.org/10.5194/essd-16-1107-2024, https://doi.org/10.5194/essd-16-1107-2024, 2024
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In this paper, we present the first edition of a global database compiling previously published and unpublished measurements of dissolved organic matter (DOM) collected in coastal waters (CoastDOM v1). Overall, the CoastDOM v1 dataset will be useful to identify global spatial and temporal patterns and to facilitate reuse in studies aimed at better characterizing local biogeochemical processes and identifying a baseline for modelling future changes in coastal waters.
Vao Fenotiana Razanamahandry, Marjolein Dewaele, Gerard Govers, Liesa Brosens, Benjamin Campforts, Liesbet Jacobs, Tantely Razafimbelo, Tovonarivo Rafolisy, and Steven Bouillon
Biogeosciences, 19, 3825–3841, https://doi.org/10.5194/bg-19-3825-2022, https://doi.org/10.5194/bg-19-3825-2022, 2022
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In order to shed light on possible past vegetation shifts in the Central Highlands of Madagascar, we measured stable isotope ratios of organic carbon in soil profiles along both forested and grassland hillslope transects in the Lake Alaotra region. Our results show that the landscape of this region was more forested in the past: soils in the C4-dominated grasslands contained a substantial fraction of C3-derived carbon, increasing with depth.
Rey Harvey Suello, Simon Lucas Hernandez, Steven Bouillon, Jean-Philippe Belliard, Luis Dominguez-Granda, Marijn Van de Broek, Andrea Mishell Rosado Moncayo, John Ramos Veliz, Karem Pollette Ramirez, Gerard Govers, and Stijn Temmerman
Biogeosciences, 19, 1571–1585, https://doi.org/10.5194/bg-19-1571-2022, https://doi.org/10.5194/bg-19-1571-2022, 2022
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This research shows indications that the age of the mangrove forest and its position along a deltaic gradient (upstream–downstream) play a vital role in the amount and sources of carbon stored in the mangrove sediments. Our findings also imply that carbon capture by the mangrove ecosystem itself contributes partly but relatively little to long-term sediment organic carbon storage. This finding is particularly relevant for budgeting the potential of mangrove ecosystems to mitigate climate change.
Man Zhao, Liesbet Jacobs, Steven Bouillon, and Gerard Govers
Biogeosciences, 18, 1511–1523, https://doi.org/10.5194/bg-18-1511-2021, https://doi.org/10.5194/bg-18-1511-2021, 2021
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We investigate the relative importance of two individual factors (hydrodynamical disturbance and aquatic microbial community) that possibly control SOC decomposition rates in river systems. We found aquatic microbial organisms led to rapid SOC decomposition, while effect of mechanical disturbance is relative minor. We propose a simple conceptual model: hydrodynamic disturbance is only important when soil aggregates are strong enough to withstand the disruptive forces imposed by water immersions.
Samuel T. Wilson, Alia N. Al-Haj, Annie Bourbonnais, Claudia Frey, Robinson W. Fulweiler, John D. Kessler, Hannah K. Marchant, Jana Milucka, Nicholas E. Ray, Parvadha Suntharalingam, Brett F. Thornton, Robert C. Upstill-Goddard, Thomas S. Weber, Damian L. Arévalo-Martínez, Hermann W. Bange, Heather M. Benway, Daniele Bianchi, Alberto V. Borges, Bonnie X. Chang, Patrick M. Crill, Daniela A. del Valle, Laura Farías, Samantha B. Joye, Annette Kock, Jabrane Labidi, Cara C. Manning, John W. Pohlman, Gregor Rehder, Katy J. Sparrow, Philippe D. Tortell, Tina Treude, David L. Valentine, Bess B. Ward, Simon Yang, and Leonid N. Yurganov
Biogeosciences, 17, 5809–5828, https://doi.org/10.5194/bg-17-5809-2020, https://doi.org/10.5194/bg-17-5809-2020, 2020
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The oceans are a net source of the major greenhouse gases; however there has been little coordination of oceanic methane and nitrous oxide measurements. The scientific community has recently embarked on a series of capacity-building exercises to improve the interoperability of dissolved methane and nitrous oxide measurements. This paper derives from a workshop which discussed the challenges and opportunities for oceanic methane and nitrous oxide research in the near future.
Clare Woulds, James B. Bell, Adrian G. Glover, Steven Bouillon, and Louise S. Brown
Biogeosciences, 17, 1–12, https://doi.org/10.5194/bg-17-1-2020, https://doi.org/10.5194/bg-17-1-2020, 2020
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Sedimented hydrothermal vents occur where heated, mineral-rich (hydrothermal) water seeps through seafloor sediments. They host chemosynthetic microbes, which use chemical energy to fix dissolved carbon dioxide into sugars (chemosynthesis). We conducted carbon tracing experiments, and observed chemosynthesis at both vent and non-vent sites. Thus, chemosynthesis occurred over a much larger area than expected, suggesting it is more widespread than previously thought.
Alberto V. Borges, François Darchambeau, Thibault Lambert, Cédric Morana, George H. Allen, Ernest Tambwe, Alfred Toengaho Sembaito, Taylor Mambo, José Nlandu Wabakhangazi, Jean-Pierre Descy, Cristian R. Teodoru, and Steven Bouillon
Biogeosciences, 16, 3801–3834, https://doi.org/10.5194/bg-16-3801-2019, https://doi.org/10.5194/bg-16-3801-2019, 2019
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Tropical rivers might be strong sources of CO2 and CH4 to the atmosphere, although there is an enormous data gap. The origin of CO2 in lowland tropical rivers is not well characterized and can be from terra firme or from wetlands (flooded forests and aquatic macrophytes). We obtained a large field dataset of CO2, CH4 and N2O in the Congo, the second-largest river in the world, which allows us to quantity the emission of these greenhouse gases to the atmosphere and investigate their origin.
Gwenaël Abril and Alberto V. Borges
Biogeosciences, 16, 769–784, https://doi.org/10.5194/bg-16-769-2019, https://doi.org/10.5194/bg-16-769-2019, 2019
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Based on classical concepts in ecology, and a literature survey, we highlight the importance of flooded land as a preferential source of atmospheric carbon to aquatic systems at the global scale. Studies in terrestrial and aquatic ecosystems could be reconciled by considering the occurrence of an efficient wetland CO2 pump to river systems. New methodological approaches coupling hydrology and ecology are also necessary to improve scientific knowledge on carbon fluxes at the land–water interface.
Samuel T. Wilson, Hermann W. Bange, Damian L. Arévalo-Martínez, Jonathan Barnes, Alberto V. Borges, Ian Brown, John L. Bullister, Macarena Burgos, David W. Capelle, Michael Casso, Mercedes de la Paz, Laura Farías, Lindsay Fenwick, Sara Ferrón, Gerardo Garcia, Michael Glockzin, David M. Karl, Annette Kock, Sarah Laperriere, Cliff S. Law, Cara C. Manning, Andrew Marriner, Jukka-Pekka Myllykangas, John W. Pohlman, Andrew P. Rees, Alyson E. Santoro, Philippe D. Tortell, Robert C. Upstill-Goddard, David P. Wisegarver, Gui-Ling Zhang, and Gregor Rehder
Biogeosciences, 15, 5891–5907, https://doi.org/10.5194/bg-15-5891-2018, https://doi.org/10.5194/bg-15-5891-2018, 2018
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To determine the variability between independent measurements of dissolved methane and nitrous oxide, seawater samples were analyzed by multiple laboratories. The results revealed the influences of the different parts of the analytical process, from the initial sample collection to the calculation of the final concentrations. Recommendations are made to improve dissolved methane and nitrous oxide measurements to help preclude future analytical discrepancies between laboratories.
Trent R. Marwick, Fredrick Tamooh, Bernard Ogwoka, Alberto V. Borges, François Darchambeau, and Steven Bouillon
Biogeosciences, 15, 1683–1700, https://doi.org/10.5194/bg-15-1683-2018, https://doi.org/10.5194/bg-15-1683-2018, 2018
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A 2-year biogeochemical record provides annual sediment and element flux estimates for the non-dammed Sabaki River, Kenya, establishing a baseline for future research in light of impending construction of the first major upstream reservoir. Over 80 % of material fluxes occur across the wet season, with annual yields comparable to the adjacent, and dammed, Tana River. Observations at low-flow periods suggest large mammalian herbivores may be vectors of terrestrial subsidies to the water column.
Alberto V. Borges, Gwenaël Abril, and Steven Bouillon
Biogeosciences, 15, 1093–1114, https://doi.org/10.5194/bg-15-1093-2018, https://doi.org/10.5194/bg-15-1093-2018, 2018
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The Mekong River is among the largest on Earth and is vital for the economy of Vietnam and South East Asia and the livelihood of the local population (70 million across six countries). Numerous dams for hydropower are planned, which will affect the delivery of water and sediments to the Mekong delta, with numerous possible consequences. We report the dynamics of two greenhouse gases (CO2 and CH4) in the Mekong delta that can be used as a reference state to evaluate future changes.
Naomi Geeraert, Fred O. Omengo, Fredrick Tamooh, Trent R. Marwick, Alberto V. Borges, Gerard Govers, and Steven Bouillon
Biogeosciences Discuss., https://doi.org/10.5194/bg-2017-31, https://doi.org/10.5194/bg-2017-31, 2017
Manuscript not accepted for further review
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We observed that the relationship between the concentrations and the water discharge in the Tana River changed in wet seasons with and without flooding. Detailed sampling in those seasons is required in order to construct several rating curves and to obtain reliable flux estimates. The sediment and carbon fluxes in function of discharge will help us to asses the flux changes that can be expected when the hydrology changes due to climate change or human impact.
Thibault Lambert, Steven Bouillon, François Darchambeau, Philippe Massicotte, and Alberto V. Borges
Biogeosciences, 13, 5405–5420, https://doi.org/10.5194/bg-13-5405-2016, https://doi.org/10.5194/bg-13-5405-2016, 2016
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This paper aims to investigate the spatial variability in dissolved organic matter (DOM) in terms of both concentration and composition in the Congo River network. Stable carbon isotopes and absorption and fluorescent properties of DOM were used as proxies for DOM composition. This study shows that DOM degradation within the Congo Basin results in the transition from aromatic to aliphatic DOM as well as the role of landscape and water residence time on this transition.
Clare Woulds, Steven Bouillon, Gregory L. Cowie, Emily Drake, Jack J. Middelburg, and Ursula Witte
Biogeosciences, 13, 4343–4357, https://doi.org/10.5194/bg-13-4343-2016, https://doi.org/10.5194/bg-13-4343-2016, 2016
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Estuarine sediments are important locations for carbon cycling and burial. We used tracer experiments to investigate how site conditions affect the way in which seafloor biological communities cycle carbon. We showed that while total respiration rates are primarily determined by temperature, total carbon processing by the biological community is strongly related to
its biomass. Further, we saw a distinct pattern of carbon cycling in sandy sediment, in which uptake by bacteria dominates.
Fleur A. E. Roland, François Darchambeau, Cédric Morana, Sean A. Crowe, Bo Thamdrup, and Alberto V. Borges
Biogeosciences Discuss., https://doi.org/10.5194/bg-2016-300, https://doi.org/10.5194/bg-2016-300, 2016
Manuscript not accepted for further review
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We studied methane consumption in a tropical Great Lake (Lake Kivu, East Africa). Lake Kivu has huge methane concentrations in its deep anoxic waters, but is a very poor emitter of methane to the atmosphere, which suppose a strong methane consumption in the water column. During this study, we put in evidence high aerobic and anaerobic consumption rates, whose relative importance varied with the season (higher aerobic rates in dry season, when the oxic compartment is wider).
Thibault Lambert, Cristian R. Teodoru, Frank C. Nyoni, Steven Bouillon, François Darchambeau, Philippe Massicotte, and Alberto V. Borges
Biogeosciences, 13, 2727–2741, https://doi.org/10.5194/bg-13-2727-2016, https://doi.org/10.5194/bg-13-2727-2016, 2016
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This manuscript presents a detailed analysis of transport and transformation of dissolved organic matter along the Zambezi River and its largest tributary. A particular focus is put on the effects of floodplains/wetlands and reservoirs as well as low-flow vs. high-flow conditions on the longitudinal patterns in DOM concentration and composition. It is the first study to present such a detailed analysis for a whole, large river system, and in particular for a tropical river other than the Amazon.
N. Geeraert, F. O. Omengo, G. Govers, and S. Bouillon
Biogeosciences, 13, 517–525, https://doi.org/10.5194/bg-13-517-2016, https://doi.org/10.5194/bg-13-517-2016, 2016
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Rivers transport a large amount of carbon as dissolved organic carbon (DOC). Our incubation experiments on water of the Tana River, Kenya, showed that microbial decomposition of 10–60 % of the initial DOC occurred within the first 24–48 h. Simultaneously, there was a decrease in isotopic composition, indicating that DOC derived from C4 vegetation is preferentially decomposed. This has implications for the assessment of vegetation in a catchment based on isotope signatures of riverine carbon.
C. Morana, F. Darchambeau, F. A. E. Roland, A. V. Borges, F. Muvundja, Z. Kelemen, P. Masilya, J.-P. Descy, and S. Bouillon
Biogeosciences, 12, 4953–4963, https://doi.org/10.5194/bg-12-4953-2015, https://doi.org/10.5194/bg-12-4953-2015, 2015
C. R. Teodoru, F. C. Nyoni, A. V. Borges, F. Darchambeau, I. Nyambe, and S. Bouillon
Biogeosciences, 12, 2431–2453, https://doi.org/10.5194/bg-12-2431-2015, https://doi.org/10.5194/bg-12-2431-2015, 2015
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CO2 and CH4 concentrations and fluxes in the Zambezi River basin are well below the median/average values reported previously for tropical rivers, streams and reservoirs, and mainly controlled by the connectivity with floodplains and the presence of waterfalls and man-made reservoirs. The mass balance suggests that carbon transport to the ocean represents the major component (~60%) of the budget, while emissions to the atmosphere account for less than 40% of the total carbon yield.
C. Morana, A. V. Borges, F. A. E. Roland, F. Darchambeau, J.-P. Descy, and S. Bouillon
Biogeosciences, 12, 2077–2088, https://doi.org/10.5194/bg-12-2077-2015, https://doi.org/10.5194/bg-12-2077-2015, 2015
M. Hagens, C. P. Slomp, F. J. R. Meysman, D. Seitaj, J. Harlay, A. V. Borges, and J. J. Middelburg
Biogeosciences, 12, 1561–1583, https://doi.org/10.5194/bg-12-1561-2015, https://doi.org/10.5194/bg-12-1561-2015, 2015
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This study looks at the combined impacts of hypoxia and acidification, two major environmental stressors affecting coastal systems, in a seasonally stratified basin. Here, the surface water experiences less seasonality in pH than the bottom water despite higher process rates. This is due to a substantial reduction in the acid-base buffering capacity of the bottom water as it turns hypoxic in summer. This highlights the crucial role of the buffering capacity as a modulating factor in pH dynamics.
G. Abril, S. Bouillon, F. Darchambeau, C. R. Teodoru, T. R. Marwick, F. Tamooh, F. Ochieng Omengo, N. Geeraert, L. Deirmendjian, P. Polsenaere, and A. V. Borges
Biogeosciences, 12, 67–78, https://doi.org/10.5194/bg-12-67-2015, https://doi.org/10.5194/bg-12-67-2015, 2015
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We compared pCO2 data calculated from pH and alkalinity from those measured directly in a large array of temperate and tropical freshwaters. This revealed a large overestimation (up to 300%) of calculated pCO2 in the case of acidic and organic-rich waters, due to a contribution of organic acids anions to alkalinity and a lower buffering capacity of the carbonate system at acidic pH. Given the widespread distribution of acidic freshwaters, direct measurements of water pCO2 are encouraged.
P. Ciais, A. J. Dolman, A. Bombelli, R. Duren, A. Peregon, P. J. Rayner, C. Miller, N. Gobron, G. Kinderman, G. Marland, N. Gruber, F. Chevallier, R. J. Andres, G. Balsamo, L. Bopp, F.-M. Bréon, G. Broquet, R. Dargaville, T. J. Battin, A. Borges, H. Bovensmann, M. Buchwitz, J. Butler, J. G. Canadell, R. B. Cook, R. DeFries, R. Engelen, K. R. Gurney, C. Heinze, M. Heimann, A. Held, M. Henry, B. Law, S. Luyssaert, J. Miller, T. Moriyama, C. Moulin, R. B. Myneni, C. Nussli, M. Obersteiner, D. Ojima, Y. Pan, J.-D. Paris, S. L. Piao, B. Poulter, S. Plummer, S. Quegan, P. Raymond, M. Reichstein, L. Rivier, C. Sabine, D. Schimel, O. Tarasova, R. Valentini, R. Wang, G. van der Werf, D. Wickland, M. Williams, and C. Zehner
Biogeosciences, 11, 3547–3602, https://doi.org/10.5194/bg-11-3547-2014, https://doi.org/10.5194/bg-11-3547-2014, 2014
T. R. Marwick, F. Tamooh, B. Ogwoka, C. Teodoru, A. V. Borges, F. Darchambeau, and S. Bouillon
Biogeosciences, 11, 443–460, https://doi.org/10.5194/bg-11-443-2014, https://doi.org/10.5194/bg-11-443-2014, 2014
F. Tamooh, A. V. Borges, F. J. R. Meysman, K. Van Den Meersche, F. Dehairs, R. Merckx, and S. Bouillon
Biogeosciences, 10, 6911–6928, https://doi.org/10.5194/bg-10-6911-2013, https://doi.org/10.5194/bg-10-6911-2013, 2013
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Biogeosciences, 22, 3785–3805, https://doi.org/10.5194/bg-22-3785-2025, https://doi.org/10.5194/bg-22-3785-2025, 2025
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To investigate if greenhouse gases (GHG) emissions from ponds vary among clear-water ponds with macrophytes and turbid-water ponds with phytoplankton, we measured CO2, CH4, and N2O concentrations and emissions in two clear- and two turbid-water urban ponds in the city of Brussels from June 2021 to December 2023. Differences in CH4 ebullitive emissions were observed between clear- and turbid-water ponds but none for CO2 and N2O emissions.
Ida Bagus Mandhara Brasika, Pierre Friedlingstein, Stephen Sitch, Michael O'Sullivan, Maria Carolina Duran-Rojas, Thais Michele Rosan, Kees Klein Goldewijk, Julia Pongratz, Clemens Schwingshackl, Louise P. Chini, and George C. Hurtt
Biogeosciences, 22, 3547–3561, https://doi.org/10.5194/bg-22-3547-2025, https://doi.org/10.5194/bg-22-3547-2025, 2025
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Indonesia is the world's third-highest carbon emitter from land use change. However, there are uncertainties in the carbon emissions of Indonesia. Our best estimate of carbon emissions from land use change in Indonesia is 0.12 ± 0.02 PgC/yr with a steady trend. Despite many uncertainties created by drivers, models, and products, we also found robust agreements between these models and products. All agree that Indonesian carbon emissions from LULCC (land use and land cover change) have had no decreasing trend for the last 2 decades.
Antonio Donateo, Daniela Famulari, Donato Giovannelli, Arturo Mariani, Mauro Mazzola, Stefano Decesari, and Gianluca Pappaccogli
Biogeosciences, 22, 2889–2908, https://doi.org/10.5194/bg-22-2889-2025, https://doi.org/10.5194/bg-22-2889-2025, 2025
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This study focuses on measurements of CO2 and CH4 turbulent fluxes in tundra ecosystems in the Svalbard islands over a 2-year period. Our results reveal dynamic interactions between climatic conditions and ecosystem activities such as photosynthesis and microbial activity. In summer, photosynthesis and microbial activity increase, leading to net carbon uptake and methane consumption. Wind influences soil drying and CH4 emissions. Thermal anomalies can reduce annual carbon uptake.
Stavros Stagakis, Dominik Brunner, Junwei Li, Leif Backman, Anni Karvonen, Lionel Constantin, Leena Järvi, Minttu Havu, Jia Chen, Sophie Emberger, and Liisa Kulmala
Biogeosciences, 22, 2133–2161, https://doi.org/10.5194/bg-22-2133-2025, https://doi.org/10.5194/bg-22-2133-2025, 2025
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The balance between CO2 uptake and emissions from urban green areas is still not well understood. This study evaluated for the first time the urban park CO2 exchange simulations with four different types of biosphere model by comparing them with observations. Even though some advantages and disadvantages of the different model types were identified, there was no strong evidence that more complex models performed better than simple ones.
Chaolei Yang, Yufeng Tian, Jingqi Cui, Guangxiong He, Jingyuan Li, Canfeng Li, Haichuang Duan, Zong Wei, Liu Yan, Xin Xia, Yong Huang, Aihua Jiang, and Yuwen Feng
Biogeosciences, 22, 2097–2114, https://doi.org/10.5194/bg-22-2097-2025, https://doi.org/10.5194/bg-22-2097-2025, 2025
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Due to the influence of extreme-drought events in southwest China, the carbon sequestration capacity of the open savanna in the dry–hot valley of the Jinsha River has been significantly diminished, with soil water content being the key environmental factor governing CO2 flux. Under the climate scenario where the frequency and severity of extreme droughts are expected to continue increasing, the CO2 emissions from the open savanna are also anticipated to rise persistently.
Maren Jenrich, Juliane Wolter, Susanne Liebner, Christian Knoblauch, Guido Grosse, Fiona Giebeler, Dustin Whalen, and Jens Strauss
Biogeosciences, 22, 2069–2086, https://doi.org/10.5194/bg-22-2069-2025, https://doi.org/10.5194/bg-22-2069-2025, 2025
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Climate warming in the Arctic is causing the erosion of permafrost coasts and the transformation of permafrost lakes into lagoons. To understand how this affects greenhouse gas (GHG) emissions, we studied carbon dioxide (CO₂) and methane (CH₄) production in lagoons with varying sea connections. Younger lagoons produce more CH₄, while CO₂ increases under more marine conditions. Flooding of permafrost lowlands due to rising sea levels may lead to higher GHG emissions from Arctic coasts in future.
Amélie Pouliot, Isabelle Laurion, Antoine Thiboult, and Daniel F. Nadeau
EGUsphere, https://doi.org/10.5194/egusphere-2025-1497, https://doi.org/10.5194/egusphere-2025-1497, 2025
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Small thermokarst lakes release greenhouse gases (GHGs) as permafrost thaws, but most studies focus on diurnal measurements, potentially overlooking significant variations. We measured GHG fluxes from 2 lakes in Nunavik over twosummers—one colder, one warmer—alongside two years of continuous water column monitoring. Fluxes were higher in the warmer summer, with strong day-night differences. Our findings show that accurate GHG estimates require full diel measurements and seasonal considerations.
Tea Thum, Tuuli Miinalainen, Outi Seppälä, Holly Croft, Cheryl Rogers, Ralf Staebler, Silvia Caldararu, and Sönke Zaehle
Biogeosciences, 22, 1781–1807, https://doi.org/10.5194/bg-22-1781-2025, https://doi.org/10.5194/bg-22-1781-2025, 2025
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Climate change has the potential to influence the carbon sequestration potential of terrestrial ecosystems, and here the nitrogen cycle is also important. We used the terrestrial biosphere model QUINCY (QUantifying Interactions between terrestrial Nutrient CYcles and the climate system) in a mixed deciduous forest in Canada. We investigated the usefulness of using the leaf area index and leaf chlorophyll content to improve the parameterization of the model. This work paves the way for using spaceborne observations in model parameterizations, also including information on the nitrogen cycle.
An Truong Nguyen, Gwenaël Abril, Jacob S. Diamond, Raphaël Lamouroux, Cécile Martinet, and Florentina Moatar
EGUsphere, https://doi.org/10.5194/egusphere-2025-1478, https://doi.org/10.5194/egusphere-2025-1478, 2025
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This 32-year study of France’s Loire River shows cleaner water reduced carbon dioxide emissions by 62 %, despite increased contributions from aquatic plant activity. Seasonal emissions were higher in autumn than spring, while long-term declines were driven by reduced external carbon inputs from groundwater and soils. Results highlight how ecosystem changes influence rivers' role in global carbon cycles and climate management.
Patrick Aurich, Uwe Spank, and Matthias Koschorreck
Biogeosciences, 22, 1697–1709, https://doi.org/10.5194/bg-22-1697-2025, https://doi.org/10.5194/bg-22-1697-2025, 2025
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Lakes can be sources and sinks of the greenhouse gas carbon dioxide. The gas exchange between the atmosphere and the water can be measured by taking gas samples from them. However, the depth of water samples is not well defined, which may cause errors. We hypothesized that gradients of CO2 concentrations develop under the surface when wind speeds are very low. Our measurements show that such a gradient can occur on calm nights, potentially shifting lakes from a CO2 sink to a source.
Roxanne Daelman, Marijn Bauters, Matti Barthel, Emmanuel Bulonza, Lodewijk Lefevre, José Mbifo, Johan Six, Klaus Butterbach-Bahl, Benjamin Wolf, Ralf Kiese, and Pascal Boeckx
Biogeosciences, 22, 1529–1542, https://doi.org/10.5194/bg-22-1529-2025, https://doi.org/10.5194/bg-22-1529-2025, 2025
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The increase in atmospheric concentrations of several greenhouse gases (GHGs) since 1750 is attributed to human activity. However, natural ecosystems, such as tropical forests, also contribute to GHG budgets. The Congo Basin hosts the second largest tropical forest and is understudied. In this study, measurements of soil GHG exchange were carried out during 16 months in a tropical forest in the Congo Basin. Overall, the soil acted as a major source of CO2 and N2O and a minor sink of CH4.
Aldis Butlers, Raija Laiho, Andis Lazdiņš, Thomas Schindler, Kaido Soosaar, Jyrki Jauhiainen, Arta Bārdule, Muhammad Kamil-Sardar, Ieva Līcīte, Valters Samariks, Andreas Haberl, Hanna Vahter, Dovilė Čiuldienė, Jani Anttila, and Kęstutis Armolaitis
EGUsphere, https://doi.org/10.5194/egusphere-2025-1032, https://doi.org/10.5194/egusphere-2025-1032, 2025
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A two-year study in Estonia, Latvia, and Lithuania evaluated the carbon balance of drained and undrained nutrient-rich forest organic soils, ranging from highly mineralized soils close to the threshold of organic soil definition to deep peat. The soils varied in pH, macronutrient levels, and C:N ratio, which contributed to the observed behavior of the soils demonstrating carbon sink and source dynamics under both drained and undrained conditions.
Olli-Pekka Tikkasalo, Olli Peltola, Pavel Alekseychik, Juha Heikkinen, Samuli Launiainen, Aleksi Lehtonen, Qian Li, Eduardo Martínez-García, Mikko Peltoniemi, Petri Salovaara, Ville Tuominen, and Raisa Mäkipää
Biogeosciences, 22, 1277–1300, https://doi.org/10.5194/bg-22-1277-2025, https://doi.org/10.5194/bg-22-1277-2025, 2025
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The emissions of greenhouse gases (GHGs) carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) were measured from a clear-cut peatland forest site. The measurements covered the whole year of 2022, which was the second growing season after the clear-cut. The site was a strong GHG source, and the highest emissions came from CO2, followed by N2O and CH4. A statistical model that included information on different surfaces at the site was developed to unravel surface-type-specific GHG fluxes.
Ruth Reef, Edoardo Daly, Tivanka Anandappa, Eboni-Jane Vienna-Hallam, Harriet Robertson, Matthew Peck, and Adrien Guyot
Biogeosciences, 22, 1149–1162, https://doi.org/10.5194/bg-22-1149-2025, https://doi.org/10.5194/bg-22-1149-2025, 2025
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Studies show that saltmarshes excel at capturing carbon from the atmosphere. In this study, we measured CO2 flux in an Australian temperate saltmarsh on French Island. The temperate saltmarsh exhibited strong seasonality. During the warmer growing season, the saltmarsh absorbed 10.5 g CO2 m−2 on average daily from the atmosphere. Even in winter, when plants were dormant, it continued to be a CO2 sink, albeit a smaller one. Cool temperatures and high cloud cover inhibit carbon sequestration.
Sebastian F. A. Jordan, Stefan Schloemer, Martin Krüger, Tanja Heffner, Marcus A. Horn, and Martin Blumenberg
Biogeosciences, 22, 809–830, https://doi.org/10.5194/bg-22-809-2025, https://doi.org/10.5194/bg-22-809-2025, 2025
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Using a multilayer approach, we studied the methane flux, soil gas composition, and isotopic signatures of soil methane and carbon dioxide at eight cut and buried abandoned oil wells in a peat-rich area of northern Germany. The detected methane emissions were of biogenic, peat origin and were not associated with the abandoned wells. Additional microbial analysis and methane oxidation rate measurements demonstrated a high methane emission mitigation potential in the studied peat soils.
Laura Thölix, Leif Backman, Minttu Havu, Esko Karvinen, Jesse Soininen, Justine Trémeau, Olli Nevalainen, Joyson Ahongshangbam, Leena Järvi, and Liisa Kulmala
Biogeosciences, 22, 725–749, https://doi.org/10.5194/bg-22-725-2025, https://doi.org/10.5194/bg-22-725-2025, 2025
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Cities aim for carbon neutrality and seek to understand urban vegetation's role as a carbon sink. Direct measurements are challenging, so models are used to estimate the urban carbon cycle. We evaluated model performance at estimating carbon sequestration in lawns, park trees, and urban forests in Helsinki, Finland. Models captured seasonal and annual variations well. Trees had higher sequestration rates than lawns, and irrigation often enhanced carbon sinks.
Laura M. van der Poel, Laurent V. Bataille, Bart Kruijt, Wietse Franssen, Wilma Jans, Jan Biermann, Anne Rietman, Alex J. V. Buzacott, Ype van der Velde, Ruben Boelens, and Ronald W. A. Hutjes
EGUsphere, https://doi.org/10.5194/egusphere-2025-431, https://doi.org/10.5194/egusphere-2025-431, 2025
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We combine two types of carbon dioxide (CO2) data from Dutch peatlands in a machine learning model: from fixed measurement towers and from a light research aircraft. We find that emissions increase with deeper water table depths (WTD) by 4.6 tonnes CO2 per hectare per year, per 10 cm deeper WTD on average. The effect is stronger in winter than in summer and varies between locations. This variability should be taken into account when developing mitigation measures.
Gabrielle E. Kleber, Leonard Magerl, Alexandra V. Turchyn, Stefan Schloemer, Mark Trimmer, Yizhu Zhu, and Andrew Hodson
Biogeosciences, 22, 659–674, https://doi.org/10.5194/bg-22-659-2025, https://doi.org/10.5194/bg-22-659-2025, 2025
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Our research on Svalbard shows that glacier melt rivers can transport large amounts of methane, a potent greenhouse gas. By studying a glacier over one summer, we found that its river was highly concentrated in methane, suggesting that rivers could provide a significant source of methane emissions as the Arctic warms and glaciers melt. This is the first time such emissions have been measured on Svalbard, indicating a wider environmental concern as such processes are occurring across the Arctic.
Martino E. Malerba, Blake Edwards, Lukas Schuster, Omosalewa Odebiri, Josh Glen, Rachel Kelly, Paul Phan, Alistair Grinham, and Peter I. Macreadie
EGUsphere, https://doi.org/10.31219/osf.io/54rd2, https://doi.org/10.31219/osf.io/54rd2, 2025
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The Pondi is a cost-effective, lightweight logger designed for long-term monitoring of carbon dioxide, methane, and nitrous oxide emissions in both terrestrial and aquatic ecosystems. It addresses key challenges in greenhouse gas monitoring by providing an automated, low-cost, solar-powered solution with cloud connectivity and real-time analytics. Its robust design enables deployment in diverse environmental conditions, supporting large-scale, high-resolution emission assessments.
Eeva Järvi-Laturi, Teemu Tahvanainen, Eero Koskinen, Efrén López-Blanco, Juho Lämsä, Hannu Marttila, Mikhail Mastepanov, Riku Paavola, Maria Väisänen, and Torben Røjle Christensen
EGUsphere, https://doi.org/10.5194/egusphere-2025-217, https://doi.org/10.5194/egusphere-2025-217, 2025
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Our research investigates how plant community composition influences methane emissions in a northern boreal rich fen. We measured methane fluxes year-round using manual chambers across 36 plots. Our findings suggest that sedges, particularly Carex rostrata, significantly impact the fluxes throughout the year. This study enhances our understanding of vegetation-driven methane emissions, providing valuable insights for predicting future changes in peatland methane emissions.
Eva-Marie Metz, Sanam Noreen Vardag, Sourish Basu, Martin Jung, and André Butz
Biogeosciences, 22, 555–584, https://doi.org/10.5194/bg-22-555-2025, https://doi.org/10.5194/bg-22-555-2025, 2025
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We estimate CO2 fluxes in semiarid southern Africa from 2009 to 2018 based on satellite CO2 measurements and atmospheric inverse modeling. By selecting process-based vegetation models, which agree with the satellite CO2 fluxes, we find that soil respiration mainly drives the seasonality, whereas photosynthesis substantially influences the interannual variability. Our study emphasizes the need for better representation of the response of semiarid ecosystems to soil rewetting in vegetation models.
Ella Kivimäki, Tuula Aalto, Michael Buchwitz, Kari Luojus, Jouni Pulliainen, Kimmo Rautiainen, Oliver Schneising, Anu-Maija Sundström, Johanna Tamminen, Aki Tsuruta, and Hannakaisa Lindqvist
EGUsphere, https://doi.org/10.5194/egusphere-2025-249, https://doi.org/10.5194/egusphere-2025-249, 2025
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We investigate how environmental variables influencing natural methane fluxes explain the large-scale seasonal variability of satellite-observed methane at Northern high latitudes. Our findings show that soil moisture, snow cover, and soil temperature have the strongest influence, with snowmelt playing a surprisingly significant role, likely through soil isolation and wetting. This study highlights the value of multi-satellite observations for understanding large-scale wetland emissions.
Jérémy Mayen, Pierre Polsenaere, Aurore Regaudie de Gioux, Jonathan Deborde, Karine Collin, Yoann Le Merrer, Élodie Foucault, Vincent Ouisse, Laurent André, Marie Arnaud, Pierre Kostyrka, Éric Lamaud, Gwenaël Abril, and Philippe Souchu
EGUsphere, https://doi.org/10.5194/egusphere-2025-335, https://doi.org/10.5194/egusphere-2025-335, 2025
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In a salt marsh, we performed seasonal 24-h cycles to look for aquatic metabolism influence on water carbon dynamics and net ecosystem CO2 exchanges (NEE). From high to low tide in winter, marsh anaerobic respiration induced the highest levels of dissolved inorganic carbon and alkalinity. On the contrary, in spring and summer, marsh primary production led to CO2-depleted water exportations downstream. Aquatic heterotrophy at high tide can influence NEE during the highest immersion levels only.
Jacqueline Kay Knutson, François Clayer, Peter Dörsch, Sebastian Westermann, and Heleen A. de Wit
EGUsphere, https://doi.org/10.5194/egusphere-2025-184, https://doi.org/10.5194/egusphere-2025-184, 2025
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Thawing permafrost at Iškoras in northern Norway is transforming peat plateaus into thermokarst ponds and wetlands. These small ponds show striking oversaturation of dissolved greenhouse gases like carbon dioxide (CO2) and methane (CH4), partly due to organic matter processing. Streams nearby emit CO2 driven by turbulence. As permafrost disappears, carbon dynamics will change, potentially increasing emissions of CH4. This study highlights the need to integrate these changes into climate models.
Tuula Aalto, Aki Tsuruta, Jarmo Mäkelä, Jurek Müller, Maria Tenkanen, Eleanor Burke, Sarah Chadburn, Yao Gao, Vilma Mannisenaho, Thomas Kleinen, Hanna Lee, Antti Leppänen, Tiina Markkanen, Stefano Materia, Paul A. Miller, Daniele Peano, Olli Peltola, Benjamin Poulter, Maarit Raivonen, Marielle Saunois, David Wårlind, and Sönke Zaehle
Biogeosciences, 22, 323–340, https://doi.org/10.5194/bg-22-323-2025, https://doi.org/10.5194/bg-22-323-2025, 2025
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Wetland methane responses to temperature and precipitation were studied in a boreal wetland-rich region in northern Europe using ecosystem models, atmospheric inversions, and upscaled flux observations. The ecosystem models differed in their responses to temperature and precipitation and in their seasonality. However, multi-model means, inversions, and upscaled fluxes had similar seasonality, and they suggested co-limitation by temperature and precipitation.
Zhen Zhang, Benjamin Poulter, Joe R. Melton, William J. Riley, George H. Allen, David J. Beerling, Philippe Bousquet, Josep G. Canadell, Etienne Fluet-Chouinard, Philippe Ciais, Nicola Gedney, Peter O. Hopcroft, Akihiko Ito, Robert B. Jackson, Atul K. Jain, Katherine Jensen, Fortunat Joos, Thomas Kleinen, Sara H. Knox, Tingting Li, Xin Li, Xiangyu Liu, Kyle McDonald, Gavin McNicol, Paul A. Miller, Jurek Müller, Prabir K. Patra, Changhui Peng, Shushi Peng, Zhangcai Qin, Ryan M. Riggs, Marielle Saunois, Qing Sun, Hanqin Tian, Xiaoming Xu, Yuanzhi Yao, Yi Xi, Wenxin Zhang, Qing Zhu, Qiuan Zhu, and Qianlai Zhuang
Biogeosciences, 22, 305–321, https://doi.org/10.5194/bg-22-305-2025, https://doi.org/10.5194/bg-22-305-2025, 2025
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This study assesses global methane emissions from wetlands between 2000 and 2020 using multiple models. We found that wetland emissions increased by 6–7 Tg CH4 yr-1 in the 2010s compared to the 2000s. Rising temperatures primarily drove this increase, while changes in precipitation and CO2 levels also played roles. Our findings highlight the importance of wetlands in the global methane budget and the need for continuous monitoring to understand their impact on climate change.
Lorena Carrasco-Barea, Dolors Verdaguer, Maria Gispert, Xavier D. Quintana, Hélène Bourhis, and Laura Llorens
Biogeosciences, 22, 289–304, https://doi.org/10.5194/bg-22-289-2025, https://doi.org/10.5194/bg-22-289-2025, 2025
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Carbon dioxide fluxes have been measured seasonally in four plant species in a Mediterranean non-tidal salt marsh, highlighting the high carbon removal potential that these species have. Carbon dioxide and methane emissions from soil showed high variability among the habitats studied, and they were generally higher than those observed in tidal salt marshes. Our results are important for making more accurate predictions regarding carbon emissions from these ecosystems.
Ekaterina Ezhova, Topi Laanti, Anna Lintunen, Pasi Kolari, Tuomo Nieminen, Ivan Mammarella, Keijo Heljanko, and Markku Kulmala
Biogeosciences, 22, 257–288, https://doi.org/10.5194/bg-22-257-2025, https://doi.org/10.5194/bg-22-257-2025, 2025
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Machine learning (ML) models are gaining popularity in biogeosciences. They are applied as gap-filling methods and used to upscale carbon fluxes to larger areas. Here we use explainable artificial intelligence (XAI) methods to elucidate the performance of machine learning models for carbon dioxide fluxes in boreal forests. We show that statistically equal models treat input variables differently. XAI methods can help scientists make informed decisions when applying ML models in their research.
Jessica Breavington, Alexandra Steckbauer, Chuancheng Fu, Mongi Ennasri, and Carlos M. Duarte
Biogeosciences, 22, 117–134, https://doi.org/10.5194/bg-22-117-2025, https://doi.org/10.5194/bg-22-117-2025, 2025
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Mangrove carbon storage in the Red Sea is lower than average due to challenging growth conditions. We collected mangrove soil cores over multiple seasons to measure greenhouse gas (GHG) flux of carbon dioxide and methane. GHG emissions are a small offset to mangrove carbon storage overall but punctuated by periods of high emission. This variation is linked to environmental and soil properties, which were also measured. The findings aid understanding of GHG dynamics in arid mangrove ecosystems.
Alouette van Hove, Kristoffer Aalstad, Vibeke Lind, Claudia Arndt, Vincent Odongo, Rodolfo Ceriani, Francesco Fava, John Hulth, and Norbert Pirk
EGUsphere, https://doi.org/10.5194/egusphere-2024-3994, https://doi.org/10.5194/egusphere-2024-3994, 2025
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Research on methane emissions from African livestock is limited. We used a probabilistic method fusing drone and flux tower observations with an atmospheric model to estimate emissions from various herds. This approach proved robust under non-stationary wind conditions and effective in estimating emissions as low as 100 g h-1. We also detected herd locations using spectral anomalies in satellite data. Our approach can be used to estimate diverse sources, thereby improving emission inventories.
Boris Ťupek, Aleksi Lehtonen, Stefano Manzoni, Elisa Bruni, Petr Baldrian, Etienne Richy, Bartosz Adamczyk, Bertrand Guenet, and Raisa Mäkipää
EGUsphere, https://doi.org/10.5194/egusphere-2024-3813, https://doi.org/10.5194/egusphere-2024-3813, 2024
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We explored soil microbial respiration (Rh) kinetics of low-dose and long-term N fertilization in N-limited boreal forest in connection to CH₄, and N₂O fluxes, soil, and tree C sinks. The insights show that N fertilization effects C retention in boreal forest soils through modifying Rh sensitivities to soil temperature and moisture. The key findings reveal that N-enriched soils exhibited reduced sensitivity of Rh to moisture, which on annual level contributes to enhanced soil C sequestration.
Johnathan Daniel Maxey, Neil D. Hartstein, Hermann W. Bange, and Moritz Müller
Biogeosciences, 21, 5613–5637, https://doi.org/10.5194/bg-21-5613-2024, https://doi.org/10.5194/bg-21-5613-2024, 2024
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The distribution of N2O in fjord-like estuaries is poorly described in the Southern Hemisphere. Our study describes N2O distribution and its drivers in one such system in Macquarie Harbour, Tasmania. Water samples were collected seasonally in 2022 and 2023. Results show the system removes atmospheric N2O when river flow is high, whereas the system emits N2O when the river flow is low. N2O generated in basins is intercepted by the surface water and exported to the ocean during high river flow.
Wael Al Hamwi, Maren Dubbert, Jörg Schaller, Matthias Lück, Marten Schmidt, and Mathias Hoffmann
Biogeosciences, 21, 5639–5651, https://doi.org/10.5194/bg-21-5639-2024, https://doi.org/10.5194/bg-21-5639-2024, 2024
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We present a fully automatic, low-cost soil–plant enclosure system to monitor CO2 and evapotranspiration fluxes within greenhouse experiments. It operates in two modes: independent, using low-cost sensors, and dependent, where multiple chambers connect to a single gas analyzer via a low-cost multiplexer. This system provides precise, accurate measurements and high temporal resolution, enabling comprehensive monitoring of plant–soil responses to various treatments and conditions.
Rui Su, Kexin Li, Nannan Wang, Fenghui Yuan, Ying Zhao, Yunjiang Zuo, Ying Sun, Liyuan He, Xiaofeng Xu, and Lihua Zhang
EGUsphere, https://doi.org/10.5194/egusphere-2024-3347, https://doi.org/10.5194/egusphere-2024-3347, 2024
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This research examines the effect of sulfate on methane oxidation in soil, finding that sulfate may facilitate methane oxidation. Considering methane's role as a greenhouse gas and rising sulfate deposition, the study aims to predict changes in methane oxidation due to acid deposition. Future experiments will explore microbial mechanisms, as sulfate reduces methane emissions while enhancing its consumption, providing insights for mitigation strategies.
Zhao-Jun Yong, Wei-Jen Lin, Chiao-Wen Lin, and Hsing-Juh Lin
Biogeosciences, 21, 5247–5260, https://doi.org/10.5194/bg-21-5247-2024, https://doi.org/10.5194/bg-21-5247-2024, 2024
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We measured CO2 and CH4 fluxes from mangrove stems and soils of Avicennia marina and Kandelia obovata during tidal cycles. Both stem types served as CO2 and CH4 sources, emitting less CH4 than soils, with no difference in CO2 flux. While A. marina stems showed increased CO2 fluxes from low to high tides, they acted as a CH4 sink before flooding and as a source after ebbing. However, K. obovata stems showed no flux pattern. This study highlights the need to consider tidal influence and species.
Ihab Alfadhel, Ignacio Peralta-Maraver, Isabel Reche, Enrique P. Sánchez-Cañete, Sergio Aranda-Barranco, Eva Rodríguez-Velasco, Andrew S. Kowalski, and Penélope Serrano-Ortiz
Biogeosciences, 21, 5117–5129, https://doi.org/10.5194/bg-21-5117-2024, https://doi.org/10.5194/bg-21-5117-2024, 2024
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Inland saline lakes are crucial in the global carbon cycle, but increased droughts may alter their carbon exchange capacity. We measured CO2 and CH4 fluxes in a Mediterranean saline lake using the eddy covariance method under dry and wet conditions. We found the lake acts as a carbon sink during wet periods but not during droughts. These results highlight the importance of saline lakes in carbon sequestration and their vulnerability to climate-change-induced droughts.
Nathaniel B. Weston, Cynthia Troy, Patrick J. Kearns, Jennifer L. Bowen, William Porubsky, Christelle Hyacinthe, Christof Meile, Philippe Van Cappellen, and Samantha B. Joye
Biogeosciences, 21, 4837–4851, https://doi.org/10.5194/bg-21-4837-2024, https://doi.org/10.5194/bg-21-4837-2024, 2024
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Nitrous oxide (N2O) is a potent greenhouse and ozone-depleting gas produced largely from microbial nitrogen cycling processes, and human activities have resulted in increases in atmospheric N2O. We investigate the role of physical and chemical disturbances to soils and sediments in N2O production. We demonstrate that physicochemical perturbation increases N2O production, microbial community adapts over time, and initial perturbation appears to confer resilience to subsequent disturbance.
Sigrid Trier Kjær, Sebastian Westermann, Nora Nedkvitne, and Peter Dörsch
Biogeosciences, 21, 4723–4737, https://doi.org/10.5194/bg-21-4723-2024, https://doi.org/10.5194/bg-21-4723-2024, 2024
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Permafrost peatlands are thawing due to climate change, releasing large quantities of carbon that degrades upon thawing and is released as CO2, CH4 or dissolved organic carbon (DOC). We incubated thawed Norwegian permafrost peat plateaus and thermokarst pond sediment found next to permafrost for up to 350 d to measure carbon loss. CO2 production was initially the highest, whereas CH4 production increased over time. The largest carbon loss was measured at the top of the peat plateau core as DOC.
Olivier Bouriaud, Ernst-Detlef Schulze, Konstantin Gregor, Issam Bourkhris, Peter Högberg, Roland Irslinger, Phillip Papastefanou, Julia Pongratz, Anja Rammig, Riccardo Valentini, and Christian Körner
EGUsphere, https://doi.org/10.5194/egusphere-2024-3092, https://doi.org/10.5194/egusphere-2024-3092, 2024
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The impact of harvesting on forests' carbon sink capacities is debated. One view is that their sink strength is resilient to harvesting, the other that it disrupts these capacities. Our work shows that leaf area index (LAI) has been overlooked in this discussion. We found that temperate forests' carbon uptake is largely insensitive to variations in LAI beyond about 4 m² m-², but that forests operate at higher levels.
Silvie Lainela, Erik Jacobs, Stella-Theresa Luik, Gregor Rehder, and Urmas Lips
Biogeosciences, 21, 4495–4519, https://doi.org/10.5194/bg-21-4495-2024, https://doi.org/10.5194/bg-21-4495-2024, 2024
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We evaluate the variability of carbon dioxide and methane in the surface layer of the north-eastern basins of the Baltic Sea in 2018. We show that the shallower coastal areas have considerably higher spatial variability and seasonal amplitude of surface layer pCO2 and cCH4 than measured in the offshore areas of the Baltic Sea. Despite this high variability, caused mostly by coastal physical processes, the average annual air–sea CO2 fluxes differed only marginally between the sub-basins.
Martti Honkanen, Mika Aurela, Juha Hatakka, Lumi Haraguchi, Sami Kielosto, Timo Mäkelä, Jukka Seppälä, Simo-Matti Siiriä, Ken Stenbäck, Juha-Pekka Tuovinen, Pasi Ylöstalo, and Lauri Laakso
Biogeosciences, 21, 4341–4359, https://doi.org/10.5194/bg-21-4341-2024, https://doi.org/10.5194/bg-21-4341-2024, 2024
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The exchange of CO2 between the sea and the atmosphere was studied in the Archipelago Sea, Baltic Sea, in 2017–2021, using an eddy covariance technique. The sea acted as a net source of CO2 with an average yearly emission of 27.1 gC m-2 yr-1, indicating that the marine ecosystem respired carbon that originated elsewhere. The yearly CO2 emission varied between 18.2–39.2 gC m-2 yr-1, mostly due to the yearly variation of ecosystem carbon uptake.
Ralf C. H. Aben, Daniël van de Craats, Jim Boonman, Stijn H. Peeters, Bart Vriend, Coline C. F. Boonman, Ype van der Velde, Gilles Erkens, and Merit van den Berg
Biogeosciences, 21, 4099–4118, https://doi.org/10.5194/bg-21-4099-2024, https://doi.org/10.5194/bg-21-4099-2024, 2024
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Drained peatlands cause high CO2 emissions. We assessed the effectiveness of subsurface water infiltration systems (WISs) in reducing CO2 emissions related to increases in water table depth (WTD) on 12 sites for up to 4 years. Results show WISs markedly reduced emissions by 2.1 t CO2-C ha-1 yr-1. The relationship between the amount of carbon above the WTD and CO2 emission was stronger than the relationship between WTD and emission. Long-term monitoring is crucial for accurate emission estimates.
Ingeborg Bussmann, Eric P. Achterberg, Holger Brix, Nicolas Brüggemann, Götz Flöser, Claudia Schütze, and Philipp Fischer
Biogeosciences, 21, 3819–3838, https://doi.org/10.5194/bg-21-3819-2024, https://doi.org/10.5194/bg-21-3819-2024, 2024
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Methane (CH4) is an important greenhouse gas and contributes to climate warming. However, the input of CH4 from coastal areas to the atmosphere is not well defined. Dissolved and atmospheric CH4 was determined at high spatial resolution in or above the North Sea. The atmospheric CH4 concentration was mainly influenced by wind direction. With our detailed study on the spatial distribution of CH4 fluxes we were able to provide a detailed and more realistic estimation of coastal CH4 fluxes.
Niu Zhu, Jinniu Wang, Dongliang Luo, Xufeng Wang, Cheng Shen, and Ning Wu
Biogeosciences, 21, 3509–3522, https://doi.org/10.5194/bg-21-3509-2024, https://doi.org/10.5194/bg-21-3509-2024, 2024
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Our study delves into the vital role of subalpine forests in the Qinghai–Tibet Plateau as carbon sinks in the context of climate change. Utilizing advanced eddy covariance systems, we uncover their significant carbon sequestration potential, observing distinct seasonal patterns influenced by temperature, humidity, and radiation. Notably, these forests exhibit robust carbon absorption, with potential implications for global carbon balance.
Colette L. Kelly, Nicole M. Travis, Pascale Anabelle Baya, Claudia Frey, Xin Sun, Bess B. Ward, and Karen L. Casciotti
Biogeosciences, 21, 3215–3238, https://doi.org/10.5194/bg-21-3215-2024, https://doi.org/10.5194/bg-21-3215-2024, 2024
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Nitrous oxide, a potent greenhouse gas, accumulates in regions of the ocean that are low in dissolved oxygen. We used a novel combination of chemical tracers to determine how nitrous oxide is produced in one of these regions, the eastern tropical North Pacific Ocean. Our experiments showed that the two most important sources of nitrous oxide under low-oxygen conditions are denitrification, an anaerobic process, and a novel “hybrid” process performed by ammonia-oxidizing archaea.
Hella van Asperen, Thorsten Warneke, Alessandro Carioca de Araújo, Bruce Forsberg, Sávio José Filgueiras Ferreira, Thomas Röckmann, Carina van der Veen, Sipko Bulthuis, Leonardo Ramos de Oliveira, Thiago de Lima Xavier, Jailson da Mata, Marta de Oliveira Sá, Paulo Ricardo Teixeira, Julie Andrews de França e Silva, Susan Trumbore, and Justus Notholt
Biogeosciences, 21, 3183–3199, https://doi.org/10.5194/bg-21-3183-2024, https://doi.org/10.5194/bg-21-3183-2024, 2024
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Carbon monoxide (CO) is regarded as an important indirect greenhouse gas. Soils can emit and take up CO, but, until now, uncertainty remains as to which process dominates in tropical rainforests. We present the first soil CO flux measurements from a tropical rainforest. Based on our observations, we report that tropical rainforest soils are a net source of CO. In addition, we show that valley streams and inundated areas are likely additional hot spots of CO in the ecosystem.
Yélognissè Agbohessou, Claire Delon, Manuela Grippa, Eric Mougin, Daouda Ngom, Espoir Koudjo Gaglo, Ousmane Ndiaye, Paulo Salgado, and Olivier Roupsard
Biogeosciences, 21, 2811–2837, https://doi.org/10.5194/bg-21-2811-2024, https://doi.org/10.5194/bg-21-2811-2024, 2024
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Emissions of greenhouse gases in the Sahel are not well represented because they are considered weak compared to the rest of the world. However, natural areas in the Sahel emit carbon dioxide and nitrous oxides, which need to be assessed because of extended surfaces. We propose an assessment of such emissions in Sahelian silvopastoral systems and of how they are influenced by environmental characteristics. These results are essential to inform climate change strategies in the region.
Merit van den Berg, Thomas M. Gremmen, Renske J. E. Vroom, Jacobus van Huissteden, Jim Boonman, Corine J. A. van Huissteden, Ype van der Velde, Alfons J. P. Smolders, and Bas P. van de Riet
Biogeosciences, 21, 2669–2690, https://doi.org/10.5194/bg-21-2669-2024, https://doi.org/10.5194/bg-21-2669-2024, 2024
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Drained peatlands emit 3 % of the global greenhouse gas emissions. Paludiculture is a way to reduce CO2 emissions while at the same time generating an income for landowners. The side effect is the potentially high methane emissions. We found very high methane emissions for broadleaf cattail compared with narrowleaf cattail and water fern. The rewetting was, however, effective to stop CO2 emissions for all species. The highest potential to reduce greenhouse gas emissions had narrowleaf cattail.
Thea H. Heimdal, Galen A. McKinley, Adrienne J. Sutton, Amanda R. Fay, and Lucas Gloege
Biogeosciences, 21, 2159–2176, https://doi.org/10.5194/bg-21-2159-2024, https://doi.org/10.5194/bg-21-2159-2024, 2024
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Measurements of ocean carbon are limited in time and space. Machine learning algorithms are therefore used to reconstruct ocean carbon where observations do not exist. Improving these reconstructions is important in order to accurately estimate how much carbon the ocean absorbs from the atmosphere. In this study, we find that a small addition of observations from the Southern Ocean, obtained by autonomous sampling platforms, could significantly improve the reconstructions.
Guilherme L. Torres Mendonça, Julia Pongratz, and Christian H. Reick
Biogeosciences, 21, 1923–1960, https://doi.org/10.5194/bg-21-1923-2024, https://doi.org/10.5194/bg-21-1923-2024, 2024
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We study the timescale dependence of airborne fraction and underlying feedbacks by a theory of the climate–carbon system. Using simulations we show the predictive power of this theory and find that (1) this fraction generally decreases for increasing timescales and (2) at all timescales the total feedback is negative and the model spread in a single feedback causes the spread in the airborne fraction. Our study indicates that those are properties of the system, independently of the scenario.
Cited articles
Bastviken, D., Ejlertsson, J., Sundh, I., and Tranvik, L.: Methane as a
source of carbon and energy for lake pelagic food webs, Ecology, 84,
969–981, 2003.
Bastviken, D., Tranvik, L. J., Downing, J. A., Crill, P. M., and
Enrich-Prast, A.: Freshwater methane emissions offset the continental carbon
sink, Science, 331, 50–50, 2011.
Baines, S. B. and Pace, M. L: The production of dissolved organic matter
by phytoplankton and its importance to bacteria: patterns across marine and
freshwater systems, Limnol. Oceanogr., 36, 1078–1090, https://doi.org/10.4319/lo.1991.36.6.1078, 1991.
Bishop, N. I.: The influence of the herbicide, DCMU, on the oxygen-evolving
system of photosynthesis, Biochim. Biophys. Acta, 27, 205–206,
https://doi.org/10.1016/0006-3002(58)90313-5, 1958.
Bižić, M., Ionescu, D., Günthel, M., Tang, K. W., and Grossart,
H. P.: Oxic Methane Cycling: New Evidence for Methane Formation in Oxic Lake
Water, Biogenesis of Hydrocarbons, 1, 1–22, 2018.
Bižić, M., Klintzsch, T., Ionescu, D., Hindiyeh, M. Y., Günthel,
M., Muro-Pastor, A. M., Eckert, W., Urich, T., and Grossart, H. P.: Aquatic
and terrestrial cyanobacteria produce methane, Sci. Adv., 6,
eaax5343, https://doi.org/10.1126/sciadv.aax5343, 2020.
Bogard, M. J., Del Giorgio, P. A., Boutet, L., Chaves, M. C. G., Prairie, Y.
T., Merante, A., and Derry, A. M.: Oxic water column methanogenesis as a
major component of aquatic CH4 fluxes, Nat. Commun., 5, 5350, https://doi.org/10.1038/ncomms6350, 2014.
Borges, A. V., Darchambeau, F., Teodoru, C. R., Marwick, T. R., Tamooh, F.,
Geeraert, N., Morana, C., Okuku, E., and Bouillon, S.: Globally significant
greenhouse-gas emissions from African inland waters, Nat. Geosci.,
8, 637–642, 2015.
Bruhn, D., Møller, I. M., Mikkelsen, T. N., and Ambus, P.: Terrestrial
plant methane production and emission, Physiol. Plantarum, 144,
201–209, https://doi.org/10.1111/j.1399-3054.2011.01551, 2012.
Cole, J. J. and Caraco, N. F.: Atmospheric exchange of carbon dioxide in a
low-wind oligotrophic lake measured by the addition of SF6, Limnol.
Oceanogr., 43, 647–656, https://doi.org/10.4319/lo.1998.43.4.0647, 1998.
Damm, E., Helmke, E., Thoms, S., Schauer, U., Nöthig, E., Bakker, K.,
and Kiene, R. P.: Methane production in aerobic oligotrophic surface water
in the central Arctic Ocean, Biogeosciences, 7, 1099–1108, https://doi.org/10.5194/bg-7-1099-2010, 2010.
DelSontro, T., McGinnis, D. F., Wehrli, B., and Ostrovsky, I.: Size does
matter: Importance of large bubbles and small-scale hot spots for methane
transport, Environ. Sci. Technol., 49, 1268–1276, https://doi.org/10.1021/es5054286,
2015.
DelSontro, T., del Giorgio, P. A., and Prairie, Y. T.: No longer a paradox:
the interaction between physical transport and biological processes explains
the spatial distribution of surface water methane within and across lakes,
Ecosystems, 21, 1073–1087, https://doi.org/10.1007/s10021-017-0205-1, 2018.
Delwiche, K. B. and Hemond, H. F.: Methane bubble size distributions, flux,
and dissolution in a freshwater lake, Environ. Sci. Technol., 51, 13733–13739,
https://doi.org/10.1021/acs.est.7b04243, 2017.
Denman, S. E., Tomkins, N. W., and McSweeney, C. S.: Quantitation and
diversity analysis of ruminal methanogenic populations in response to the
antimethanogenic compound bromochloromethane, FEMS Microbiol. Ecol.,
62, 313–322, https://doi.org/10.1111/j.1574-6941.2007.00394.x, 2007.
Descy, J. P., Darchambeau, F., Lambert, T., Stoyneva-Gaertner, M. P.,
Bouillon, S., and Borges, A. V.: Phytoplankton dynamics in the Congo River,
Freshwater Biol., 62, 87–101, 2017.
Donis, D., Flury, S., Stöckli, A., Spangenberg, J. E., Vachon, D., and
McGinnis, D. F.: Full-scale evaluation of methane production under
oxic conditions in a mesotrophic lake, Nat. Commun., 8, 1661,
https://doi.org/10.1038/s41467-017-01648-4, 2017.
Dumestre, J. F., Guézennec, J., Galy-Lacaux, C., Delmas, R., Richard,
S., and Labroue, L.: Influence of Light Intensity on Methanotrophic Bacterial Activity in Petit Saut Reservoir, French Guiana, Appl. Environ. Microbiol., 65, 534–539, https://doi.org/10.1128/aem.65.2.534-539.1999, 1999.
Fernández, J. E., Peeters, F., and Hofmann, H.: On the methane paradox:
Transport from shallow water zones rather than in situ methanogenesis is the
major source of CH4 in the open surface water of lakes, J.
Geophys. Res.-Biogeo., 121, 2717–2726, https://doi.org/10.1002/2016JG003586, 2016.
French, E., Kozlowski, J. A., Mukherjee, M., Bullerjahn, G., and Bollmann,
A.: Ecophysiological characterization of ammonia-oxidizing archaea and
bacteria from freshwater, Appl. Environ. Microbiol., 78,
5773–5780, https://doi.org/10.1128/aem.00432-12, 2012.
Gillikin, D. P. and Bouillon, S.: Determination of delta O-18 of water and
delta C-13 of dissolved inorganic carbon using a simple modification of an
elemental analyzer-isotope ratio mass spectrometer: an evaluation, Rapid
Commun. Mass Sp., 21, 1475–1478,
https://doi.org/10.1002/rcm.2968, 2007.
Greinert, J. and McGinnis, D. F.: Single Bubble Dissolution Model: The
Graphical User Interface SiBu-GUI, Environ. Modell. Softw., 24, 1012–1013,
https://doi.org/10.1016/j.envsoft.2008.12.011, 2009.
Grossart, H. P., Frindte, K., Dziallas, C., Eckert, W., and Tang, K. W.:
Microbial methane production in oxygenated water column of an oligotrophic
lake, P. Natl. Acad. Sci. USA, 108, 19657–19661,
https://doi.org/10.1073/pnas.1110716108, 2011.
Günthel, M., Donis, D., Kirillin, G., Ionescu, D., Bizic, M., McGinnis,
D. F., Grossart, H. P., and Tang, K. W.: Contribution of oxic methane
production to surface methane emission in lakes and its global importance,
Nat. Commun., 10, 5497, https://doi.org/10.1038/s41467-019-13320-0, 2019.
Hama, T., Miyazaki, T., Ogawa, Y., Iwakuma, T., Takahashi, M., Otsuki, A.,
and Ichimura, S.: Measurement of photosynthetic production of a marine
phytoplankton population using a stable 13C isotope, Mar. Biol., 73,
31–36, https://doi.org/10.1007/BF00396282, 1983.
Hofmann, H., Federwisch, L., and Peeters, F.: Wave-induced release of
methane: littoral zones as source of methane in lakes, Limnol.
Oceanogr., 55, 1990–2000, https://doi.org/10.4319/lo.2010.55.5.1990, 2010.
Klindworth, A., Pruesse, E., Schweer, T., Peplies, J., Quast, C., Horn, M.,
and Glöckner, F. O.: Evaluation of general 16S ribosomal RNA gene PCR
primers for classical and next-generation se,quencing-based diversity
studies, Nucleic Acids Res., 41, e1, https://doi.org/10.1093/nar/gks808, 2013.
Klintzsch, T., Langer, G., Nehrke, G., Wieland, A., Lenhart, K., and
Keppler, F.: Methane production by three widespread marine phytoplankton
species: release rates, precursor compounds, and potential relevance for the
environment, Biogeosciences, 16, 4129–4144, https://doi.org/10.5194/bg-16-4129-2019, 2019.
Kosten, S., Huszar, V. L., Bécares, E., Costa, L. S., van Donk, E.,
Hansson, L. A., Jeppesen, E., Kruk, C., Lacerot, G., Mazzeo, N., De Meester,
L., Moss, B., Lurling, M., Noges, T., Romo, S., and Scheffer, M.: Warmer
climates boost cyanobacterial dominance in shallow lakes, Glob. Change
Biol., 18, 118–126, https://doi.org/10.1111/j.1365-2486.2011.02488.x, 2012.
Kozich, J. J., Westcott, S. L., Baxter, N. T., Highlander, S. K., and
Schloss, P. D.: Development of a dual-index sequencing strategy and curation
pipeline for analyzing amplicon sequence data on the MiSeq Illumina
sequencing platform, Appl. Environ. Microbiol., 79, 5112–5120, https://doi.org/10.1128/aem.01043-13, 2013.
Lehner, B. and Döll, P.: Development and validation of a global database of
lakes, reservoirs and wetlands, J. Hydrol., 296, 1–22, https://doi.org/10.1016/j.jhydrol.2004.03.028, 2004.
Lenhart, K., Klintzsch, T., Langer, G., Nehrke, G., Bunge, M., Schnell, S.,
and Keppler, F.: Evidence for methane production by the marine algae
Emiliania huxleyi, Biogeosciences, 13, 3163–3174,
https://doi.org/10.5194/bg-13-3163-2016, 2016.
Levine, R. L., Mosoni, L., Berlett, B. S., and Stadtman, E. R.: Methionine
residues as endogenous antioxidants in proteins, P. Natl.
Acad. Sci. USA, 93, 15036–15040, https://doi.org/10.1073/pnas.93.26.15036,
1996.
Lewis Jr., W. M.: Tropical limnology, Annu. Rev. Ecol.
Syst., 18, 159–184, https://doi.org/10.1146/annurev.es.18.110187.001111, 1987.
Martinez-Cruz, K., Sepulveda-Jauregui, A., Greene, S., Fuchs, A., Rodriguez,
M., Pansch, N., Gonsiorczyk, T., and Casper, P.: Diel variation of CH4 and
CO2 dynamics in two contrasting temperate lakes, Inland Waters, 10, 333–347, https://doi.org/10.1080/20442041.2020.1728178, 2020.
McGinnis, D. F., Greinert, J., Artemov, Y., Beaubien, S. E., and Wüest,
A. N. D. A.: Fate of rising methane bubbles in stratified waters: How much
methane reaches the atmosphere?, J. Geophys. Res.-Ocean.,
111, C09007, https://doi.org/10.1029/2005JC003183, 2006.
Mohr, W., Grosskopf, T., Wallace, D. W., and LaRoche, J.: Methodological
underestimation of oceanic nitrogen fixation rates, PloS One, 5, e12583,
https://doi.org/10.1371/journal.pone.0012583, 2010.
Montoya, J. P., Voss, M., Kahler, P., and Capone, D. G.: A Simple,
High-Precision, High-Sensitivity Tracer Assay for N (inf2) Fixation, Appl.
Environ. Microbiol., 62, 986–993, https://doi.org/10.1128/aem.62.3.986-993.1996,
1996
Morana, C., Sarmento, H., Descy, J. P., Gasol, J. M., Borges, A. V.,
Bouillon, S., and Darchambeau, F.: Production of dissolved organic matter
by phytoplankton and its uptake by heterotrophic prokaryotes in large
tropical lakes, Limnol. Oceanogr., 59,
1364–1375, https://doi.org/10.4319/lo.2014.59.4.1364, 2014.
Morana, C., Darchambeau, F., Roland, F. A. E., Borges, A. V., Muvundja, F., Kelemen, Z., Masilya, P., Descy, J.-P., and Bouillon, S.: Biogeochemistry of a large and deep tropical lake (Lake Kivu, East Africa: insights from a stable isotope study covering an annual cycle, Biogeosciences, 12, 4953–4963, https://doi.org/10.5194/bg-12-4953-2015, 2015a.
Morana, C., Borges, A. V., Roland, F. A. E., Darchambeau, F., Descy, J. P.,
and Bouillon, S.: Methanotrophy within the water column of a large
meromictic tropical lake (Lake Kivu, East Africa), Biogeosciences, 12,
2077–2088, https://doi.org/10.5194/bg-12-2077-2015, 2015b.
Mountfort, D. O. and Asher, R. A.: Effect of inorganic sulfide on the growth
and metabolism of Methanosarcina barkeri strain DM, Appl. Environ.
Microbiol., 37, 670–675, 1979.
Mugidde, R., Hecky, R. E., Hendzel, L. L., and Taylor, W. D.: Pelagic
nitrogen fixation in lake Victoria (East Africa), J. Great Lakes
Res., 29, 76–88, https://doi.org/10.1016/S0380-1330(03)70540-1, 2003.
Murase, J. and Sugimoto, A: Inhibitory effect of light on methane
oxidation in the pelagic water column of a mesotrophic lake (Lake Biwa,
Japan), Limnol. Oceanogr., 50, 1339–1343, https://doi.org/10.4319/lo.2005.50.4.1339, 2005.
Peeters, F., Fernandez, J. E., and Hofmann, H.: Sediment fluxes rather than
oxic methanogenesis explain diffusive CH4 emissions from lakes and
reservoirs, Sci. Rep., 9, 1–10, https://doi.org/10.1038/s41598-018-36530-w, 2019.
Petrillo, E., Herz, M. A. G., Fuchs, A., Reifer, D., Fuller, J., Yanovsky,
M. J., Simpson, C., Brown, J. W. S., Barta, A., Kalyna, M., and Kornblihtt,
A. R.: A chloroplast retrograde signal regulates nuclear alternative
splicing, Science, 344, 427–430, https://doi.org/10.1126/science.1250322, 2014.
Repine, J. E., Eaton, J. W., Anders, M. W., Hoidal, J. R., and Fox, R. B.:
Generation of hydroxyl radical by enzymes, chemicals, and human phagocytes
in vitro: detection with the anti-inflammatory agent, dimethyl sulfoxide,
J. Clin. Invest., 64, 1642–1651, https://doi.org/10.1172/jci109626, 1979.
Sarmento, H., Romera-Castillo, C., Lindh, M., Pinhassi, J., Sala, M. M.,
Gasol, J. M., Marassé, C., and Taylor, G. T.: Phytoplankton
species-specific release of dissolved free amino acids and their selective
consumption by bacteria, Limnol. Oceanogr., 58, 1123–1135, https://doi.org/10.4319/lo.2013.58.3.1123, 2013.
Tang, K. W., McGinnis, D. F., Ionescu, D., and Grossart, H. P.: Methane
production in oxic lake waters potentially increases aquatic methane flux to
air, Environ. Sci. Technol. Lett., 3, 227–233, https://doi.org/10.1021/acs.estlett.6b00150, 2016.
Tolar, B. B., Powers, L. C., Miller, W. L., Wallsgrove, N. J., Popp, B. N.,
and Hollibaugh, J. T.: Ammonia oxidation in the ocean can be inhibited by
nanomolar concentrations of hydrogen peroxide, Front. Mar. Sci.,
3, 237, https://doi.org/10.3389/fmars.2016.00237, 2016
Vollenweider, R. A.: Calculations models of photosynthesis-depth curves and
some implications regarding day rate estimates in primary production
measurements, Memorie dell'Istituto Italiano di Idrobiologia, 18, 425–457,
1965.
Wanninkhof, R.: Relationship between wind speed and gas exchange over the
ocean, J. Geophys. Res.-Ocean., 97, 7373–7382, https://doi.org/10.1029/92JC00188, 1992.
Yao, M., Henny, C., and Maresca, J. A.: Freshwater bacteria release methane
as a byproduct of phosphorus acquisition, Appl. Environ.
Microbiol., 82, 6994–7003, https://doi.org/10.1128/aem.02399-16, 2016.
Yvon-Durocher, G., Allen, A. P., Bastviken, D., Conrad, R., Gudasz, C.,
St-Pierre, A., Thanh-Duc, N., and Del Giorgio, P. A.: Methane fluxes show
consistent temperature dependence across microbial to ecosystem scales,
Nature, 507, 488–491, https://doi.org/10.1038/nature13164, 2014.
Short summary
A growing body of studies challenges the paradigm that methane (CH4) production occurs only under anaerobic conditions. Our field experiments revealed that oxic CH4 production is closely related to phytoplankton metabolism and is indeed a common feature in five contrasting African lakes. Nevertheless, we found that methanotrophic activity in surface waters and CH4 emissions to the atmosphere were predominantly fuelled by CH4 generated in sediments and physically transported to the surface.
A growing body of studies challenges the paradigm that methane (CH4) production occurs only...
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