Articles | Volume 19, issue 1
07 Jan 2022
Research article | 07 Jan 2022
Partitioning carbon sources between wetland and well-drained ecosystems to a tropical first-order stream – implications for carbon cycling at the watershed scale (Nyong, Cameroon)
Moussa Moustapha et al.
No articles found.
Simon Cazaurang, Manuel Marcoux, Oleg S. Pokrovsky, Sergey V. Loiko, Artem G. Lim, Stéphane Audry, Liudmila S. Shirokova, and Laurent Orgogozo
Moss, lichen and peat samples are reconstructed using X-ray tomography. Most samples can be cut down to a representative volume based on porosity. However, only homogeneous samples could be reduced to a representative volume based on hydraulic conductivity. For heterogeneous samples, a devoted pore network model is computed. The studied samples are mostly highly porous and water-conductive. These results must be put into perspective with compressibility phenomena occurring in field tests.
Julia Gensel, Marc Steven Humphries, Matthias Zabel, David Sebag, Annette Hahn, and Enno Schefuß
Biogeosciences, 19, 2881–2902,Short summary
We investigated organic matter (OM) and plant-wax-derived biomarkers in sediments and plants along the Mkhuze River to constrain OM's origin and transport pathways within South Africa's largest freshwater wetland. Presently, it efficiently captures OM, so neither transport from upstream areas nor export from the swamp occurs. Thus, we emphasize that such geomorphological features can alter OM provenance, questioning the assumption of watershed-integrated information in downstream sediments.
Robin Fentimen, Eline Feenstra, Andres Rüggeberg, Efraim Hall, Valentin Rime, Torsten Vennemann, Irka Hajdas, Antonietta Rosso, David Van Rooij, Thierry Adatte, Hendrik Vogel, Norbert Frank, and Anneleen Foubert
Clim. Past Discuss.,
Revised manuscript accepted for CPShort summary
In contrast to northeast Atlantic counterparts, coral mound build-up in the southeast Alboran Sea occurs during glacial as well as during interglacial periods and at very low aggradation rates (between 1 and 10 cm.ky−1). Interglacial benthic foraminiferal assemblages composition highlight the paramount importance of enhanced terrestrial input as a trigger for cold-water coral mound build-up. Rigid erect bryozoans may play an overlooked role in coral mound build-up during glacial periods.
Sakaros Bogning, Frédéric Frappart, Gil Mahé, Adrien Paris, Raphael Onguene, Fabien Blarel, Fernando Niño, Jacques Etame, and Jean-Jacques Braun
Proc. IAHS, 384, 181–186,Short summary
This paper investigates links between rainfall variability in the Ogooué River Basin (ORB) and El Niño Southern Oscillation (ENSO) in the Pacific Ocean. Recent hydroclimatology studies of the ORB and surrounding areas resulting in contrasting conclusions about links between rainfall variability and ENSO. Then, this work uses cross-wavelet and wavelet coherence analysis to highlight significant links between ENSO and rainfall in the ORB.
Louis Honegger, Thierry Adatte, Jorge E. Spangenberg, Miquel Poyatos-Moré, Alexandre Ortiz, Magdalena Curry, Damien Huyghe, Cai Puigdefàbregas, Miguel Garcés, Andreu Vinyoles, Luis Valero, Charlotte Läuchli, Andrés Nowak, Andrea Fildani, Julian D. Clark, and Sébastien Castelltort
Solid Earth Discuss.,
Preprint under review for SE
Lydia R. Bailey, Filippo L. Schenker, Maria Giuditta Fellin, Miriam Cobianchi, Thierry Adatte, and Vincenzo Picotti
Solid Earth, 11, 2463–2485,Short summary
The Kallipetra Basin, formed in the Late Cretaceous on the reworked Pelagonian–Axios–Vardar contact in the Hellenides, is described for the first time. We document how and when the basin evolved in response to tectonic forcings and basin inversion. Cenomanian extension and basin widening was followed by Turonian compression and basin inversion. Thrusting occurred earlier than previously reported in the literature, with a vergence to the NE, at odds with the regional SW vergence of the margin.
Robin Fentimen, Eline Feenstra, Andres Rüggeberg, Efraim Hall, Valentin Rime, Torsten Vennemann, Irka Hajdas, Antonietta Rosso, David Van Rooij, Thierry Adatte, Hendrik Vogel, Norbert Frank, Thomas Krengel, and Anneleen Foubert
Clim. Past Discuss.,
Manuscript not accepted for further reviewShort summary
This study describes the development of a cold-water Coral mound in the southeast alboran sea over the last 300 ky. Mound development follows interglacial-glacial cycles.
Louis Honegger, Thierry Adatte, Jorge E. Spangenberg, Jeremy K. Caves Rugenstein, Miquel Poyatos-Moré, Cai Puigdefàbregas, Emmanuelle Chanvry, Julian Clark, Andrea Fildani, Eric Verrechia, Kalin Kouzmanov, Matthieu Harlaux, and Sébastien Castelltort
Clim. Past, 16, 227–243,Short summary
A geochemical study of a continental section reveals a rapid global warming event (hyperthermal U), occurring ca. 50 Myr ago, only described until now in marine sediment cores. Documenting how the Earth system responded to rapid climatic shifts provides fundamental information to constrain climatic models. Our results suggest that continental deposits can be high-resolution recorders of these warmings. They also give an insight on the climatic conditions occurring during at the time.
Liudmila S. Shirokova, Artem V. Chupakov, Svetlana A. Zabelina, Natalia V. Neverova, Dahedrey Payandi-Rolland, Carole Causserand, Jan Karlsson, and Oleg S. Pokrovsky
Biogeosciences, 16, 2511–2526,Short summary
Regardless of the size and landscape context of surface water in frozen peatland in NE Europe, the bio- and photo-degradability of dissolved organic matter (DOM) over a 1-month incubation across a range of temperatures was below 10 %. We challenge the paradigm of dominance of photolysis and biodegradation in DOM processing in surface waters from frozen peatland, and we hypothesize peat pore-water DOM degradation and respiration of sediments to be the main drivers of CO2 emission in this region.
Camille Jourdan, Valérie Borrell-Estupina, David Sebag, Jean-Jacques Braun, Jean-Pierre Bedimo Bedimo, François Colin, Armand Crabit, Alain Fezeu, Cécile Llovel, Jules Rémy Ndam Ngoupayou, Benjamin Ngounou Ngatcha, Sandra Van-Exter, Eric Servat, and Roger Moussa
Hydrol. Earth Syst. Sci. Discuss.,
Publication in HESS not foreseenShort summary
In the theme Panta Rhei, this paper aims to develop a combined approach of data acquisition and a new semi-distributed non-stationary model taking into account land-use changes to reconstruct and predict annual runoff on an urban catchment in a data-sparse context. We use historical data and deploy a complementary short-term spatially-dense dedicated instrumentation. Applications were conducted on the tropical Mefou catchment (Yaoundé, Cameroon) to assess contributions of sub-catchments.
Daniel D. Richter, Sharon A. Billings, Peter M. Groffman, Eugene F. Kelly, Kathleen A. Lohse, William H. McDowell, Timothy S. White, Suzanne Anderson, Dennis D. Baldocchi, Steve Banwart, Susan Brantley, Jean J. Braun, Zachary S. Brecheisen, Charles W. Cook, Hilairy E. Hartnett, Sarah E. Hobbie, Jerome Gaillardet, Esteban Jobbagy, Hermann F. Jungkunst, Clare E. Kazanski, Jagdish Krishnaswamy, Daniel Markewitz, Katherine O'Neill, Clifford S. Riebe, Paul Schroeder, Christina Siebe, Whendee L. Silver, Aaron Thompson, Anne Verhoef, and Ganlin Zhang
Biogeosciences, 15, 4815–4832,Short summary
As knowledge in biology and geology explodes, science becomes increasingly specialized. Given the overlap of the environmental sciences, however, the explosion in knowledge inevitably creates opportunities for interconnecting the biogeosciences. Here, 30 scientists emphasize the opportunities for biogeoscience collaborations across the world’s remarkable long-term environmental research networks that can advance science and engage larger scientific and public audiences.
Chandrashekhar Deshmukh, Frédéric Guérin, Axay Vongkhamsao, Sylvie Pighini, Phetdala Oudone, Saysoulinthone Sopraseuth, Arnaud Godon, Wanidaporn Rode, Pierre Guédant, Priscia Oliva, Stéphane Audry, Cyril Zouiten, Corinne Galy-Lacaux, Henri Robain, Olivier Ribolzi, Arun Kansal, Vincent Chanudet, Stéphane Descloux, and Dominique Serça
Biogeosciences, 15, 1775–1794,Short summary
Based on an intense monitoring of CO2 concentrations and organic and inorganic carbon in the reservoir, in the rivers upstream and downstream, and of CO2 emissions from the drawdown area, we confirmed the importance of the flooded stock of organic matter as a source of C fueling emissions and we show that the drawdown area contributes, depending on the year, from 50 to 75 % of total annual gross emissions in the flat and shallow Nam Theun 2 Reservoir.
Abdelhadi El Yazidi, Michel Ramonet, Philippe Ciais, Gregoire Broquet, Isabelle Pison, Amara Abbaris, Dominik Brunner, Sebastien Conil, Marc Delmotte, Francois Gheusi, Frederic Guerin, Lynn Hazan, Nesrine Kachroudi, Giorgos Kouvarakis, Nikolaos Mihalopoulos, Leonard Rivier, and Dominique Serça
Atmos. Meas. Tech., 11, 1599–1614,
Loris Deirmendjian, Denis Loustau, Laurent Augusto, Sébastien Lafont, Christophe Chipeaux, Dominique Poirier, and Gwenaël Abril
Biogeosciences, 15, 669–691,Short summary
Carbon leaching to streams represents a very small (~ 2 %) fraction of forest net ecosystem exchange (NEE). Such weak export of carbon from forest ecosystems, at least in temperate regions, is at odds with recent studies that attempt to integrate the contribution of inland waters in the continent carbon budget. Understanding why local and global carbon mass balances strongly diverge on the proportion of land NEE exported to aquatic systems is a major challenge for research in this field.
Frédéric Guérin, Chandrashekhar Deshmukh, David Labat, Sylvie Pighini, Axay Vongkhamsao, Pierre Guédant, Wanidaporn Rode, Arnaud Godon, Vincent Chanudet, Stéphane Descloux, and Dominique Serça
Biogeosciences, 13, 3647–3663,Short summary
Methane (CH4) emissions from hydroelectric reservoirs could represent a significant fraction of global CH4 emissions from inland waters. The monitoring of methane emissions every 2 weeks at nine stations in a subtropical hydroelectric reservoir revealed that emissions could occasionally be 1 to 2 orders of magnitude higher than expected for these man-made ecosystems. Upstream of the water intake, emissions are enhanced by the water column mixing that upwells CH4-rich water to the surface.
Chandrashekhar Deshmukh, Frédéric Guérin, David Labat, Sylvie Pighini, Axay Vongkhamsao, Pierre Guédant, Wanidaporn Rode, Arnaud Godon, Vincent Chanudet, Stéphane Descloux, and Dominique Serça
Biogeosciences, 13, 1919–1932,Short summary
Methane (CH4) emissions from hydroelectric reservoirs could represent a significant fraction of global CH4 emissions from inland waters and wetlands. The first quantification of emissions downstream of a subtropical reservoir shows that they contribute only 10 to 30 % of total CH4 emissions from the reservoir. This surprisingly low contribution is due to the seasonal reservoir overturn and the effect of the turbine on re-aerating the reservoir water column.
C. Deshmukh, D. Serça, C. Delon, R. Tardif, M. Demarty, C. Jarnot, Y. Meyerfeld, V. Chanudet, P. Guédant, W. Rode, S. Descloux, and F. Guérin
Biogeosciences, 11, 4251–4269,
Related subject area
Biogeochemistry: Greenhouse GasesControls on autotrophic and heterotrophic respiration in an ombrotrophic bogEpisodic N2O emissions following tillage of a legume–grass cover crop mixtureVariation in CO2 and CH4 fluxes among land cover types in heterogeneous Arctic tundra in northeastern SiberiaResponse of vegetation and carbon fluxes to brown lemming herbivory in northern AlaskaSources of nitrous oxide and the fate of mineral nitrogen in subarctic permafrost peat soilsData-based estimates of interannual sea–air CO2 flux variations 1957–2020 and their relation to environmental driversLateral carbon export has low impact on the net ecosystem carbon balance of a polygonal tundra catchmentEvaluating alternative ebullition models for predicting peatland methane emission and its pathways via data–model fusionThe effect of Static Chamber's Base on N2O Flux in Drip IrrigationExcess soil moisture and fresh carbon input are prerequisites for methane production in podzolic soilLow biodegradability of particulate organic carbon mobilized from thaw slumps on the Peel Plateau, NT, and possible chemosynthesis and sorption effectsSpatial and temporal variation of 13C signature of methane emitted from a temperate mire: Methanogenesis, methanotrophy, and hysteresisGrazing enhances carbon cycling but reduces methane emission during peak growing season in the Siberian Pleistocene Park tundra siteIdeas and perspectives: Enhancing research and monitoring of carbon pools and land-to-atmosphere greenhouse gases exchange in developing countriesIgnoring carbon emissions from thermokarst ponds results in overestimation of tundra net carbon uptakeQuantification of potential methane emissions associated with organic matter amendments following oxic-soil inundationAssessing the spatial and temporal variability of greenhouse gas emissions from different configurations of on-site wastewater treatment system using discrete and continuous gas flux measurementDimethylated sulfur compounds in the Peruvian upwelling systemIntercomparison of methods to estimate GPP based on CO2 and COS flux measurementsExtreme events driving year-to-year differences in gross primary productivity across the USMethane gas emissions from savanna fires: what analysis of local burning regimes in a working West African landscape tell usMethane in Zackenberg Valley, NE Greenland: multidecadal growing season fluxes of a high-Arctic tundraField-scale CH4 emission at a subarctic mire with heterogeneous permafrost thaw statusEvaluation of denitrification and decomposition from three biogeochemical models using laboratory measurements of N2, N2O and CO2Temporal trends in methane emissions from a small eutrophic reservoir: the key role of a spring burstGreenhouse gases emissions from riparian wetlands: an example from the Inner Mongolia grassland region in ChinaVariability of North Atlantic CO2 fluxes for the 2000–2017 period estimated from atmospheric inverse analysesEffects of clear-fell harvesting on soil CO2, CH4, and N2O fluxes in an upland Sitka spruce stand in EnglandConventional subsoil irrigation techniques do not lower carbon emissions from drained peat meadowsDifferent responses of ecosystem CO2 and N2O emissions and CH4 uptake to seasonally asymmetric warming in an alpine grassland of the TianshanThe role of termite CH4 emissions on the ecosystem scale: a case study in the Amazon rainforestBiogeochemical and plant trait mechanisms drive enhanced methane emissions in response to whole-ecosystem warmingA decade of dimethyl sulfide (DMS), dimethylsulfoniopropionate (DMSP) and dimethyl sulfoxide (DMSO) measurements in the southwestern Baltic SeaMethane dynamics in three different Siberian water bodies under winter and summer conditionsTopography-based statistical modelling reveals high spatial variability and seasonal emission patches in forest floor methane fluxTechnical note: CO2 is not like CH4 – limits of and corrections to the headspace method to analyse pCO2 in fresh waterComparison of greenhouse gas fluxes from tropical forests and oil palm plantations on mineral soilAre there memory effects on greenhouse gas emissions (CO2, N2O and CH4) following grassland restoration?Intraseasonal variability of greenhouse gas emission factors from biomass burning in the Brazilian CerradoEvaluating stream CO2 outgassing via drifting and anchored flux chambers in a controlled flume experimentCarbon dioxide and methane exchange of a patterned subarctic fen during two contrasting growing seasonsUsing satellite data to identify the methane emission controls of South Sudan's wetlandsIdeas and perspectives: patterns of soil CO2, CH4, and N2O fluxes along an altitudinal gradient – a pilot study from an Ecuadorian neotropical montane forestEstimating immediate post-fire carbon fluxes using the eddy-covariance techniqueWater flow controls the spatial variability of methane emissions in a northern valley fen ecosystemSeasonality, drivers, and isotopic composition of soil CO2 fluxes from tropical forests of the Congo BasinSpatially resolved evaluation of Earth system models with satellite column-averaged CO2Ideas and perspectives: A strategic assessment of methane and nitrous oxide measurements in the marine environmentStem and soil nitrous oxide fluxes from rainforest and cacao agroforest on highly weathered soils in the Congo BasinMethane paradox in tropical lakes? Sedimentary fluxes rather than pelagic production in oxic conditions sustain methanotrophy and emissions to the atmosphere
Tracy E. Rankin, Nigel T. Roulet, and Tim R. Moore
Biogeosciences, 19, 3285–3303,Short summary
Peatland respiration is made up of plant and peat sources. How to separate these sources is not well known as peat respiration is not straightforward and is more influenced by vegetation dynamics than previously thought. Results of plot level measurements from shrubs and sparse grasses in a woody bog show that plants' respiration response to changes in climate is related to their different root structures, implying a difference in the mechanisms by which they obtain water resources.
Alison Bressler and Jennifer Blesh
Biogeosciences, 19, 3169–3184,Short summary
Our field experiment tested if a mixture of a nitrogen-fixing legume and non-legume cover crop could reduce nitrous oxide (N2O) emissions following tillage, compared to the legume grown alone. We found higher N2O following both legume treatments, compared to those without, and lower emissions from the cover crop mixture at one of the two test sites, suggesting that interactions between cover crop types and soil quality influence N2O emissions.
Sari Juutinen, Mika Aurela, Juha-Pekka Tuovinen, Viktor Ivakhov, Maiju Linkosalmi, Aleksi Räsänen, Tarmo Virtanen, Juha Mikola, Johanna Nyman, Emmi Vähä, Marina Loskutova, Alexander Makshtas, and Tuomas Laurila
Biogeosciences, 19, 3151–3167,Short summary
We measured CO2 and CH4 fluxes in heterogenous Arctic tundra in eastern Siberia. We found that tundra wetlands with sedge and grass vegetation contributed disproportionately to the landscape's ecosystem CO2 uptake and CH4 emissions to the atmosphere. Moreover, we observed high CH4 consumption in dry tundra, particularly in barren areas, offsetting part of the CH4 emissions from the wetlands.
Jessica Plein, Rulon W. Clark, Kyle A. Arndt, Walter C. Oechel, Douglas Stow, and Donatella Zona
Biogeosciences, 19, 2779–2794,Short summary
Tundra vegetation and the carbon balance of Arctic ecosystems can be substantially impacted by herbivory. We tested how herbivory by brown lemmings in individual enclosure plots have impacted carbon exchange of tundra ecosystems via altering carbon dioxide (CO2) and methane (CH4) fluxes. Lemmings significantly decreased net CO2 uptake while not affecting CH4 emissions. There was no significant difference in the subsequent growing season due to recovery of the vegetation.
Jenie Gil, Maija E. Marushchak, Tobias Rütting, Elizabeth M. Baggs, Tibisay Pérez, Alexander Novakovskiy, Tatiana Trubnikova, Dmitry Kaverin, Pertti J. Martikainen, and Christina Biasi
Biogeosciences, 19, 2683–2698,Short summary
N2O emissions from permafrost soils represent up to 11.6 % of total N2O emissions from natural soils, and their contribution to the global N2O budget will likely increase due to climate change. A better understanding of N2O production from permafrost soil is needed to evaluate the role of arctic ecosystems in the global N2O budget. By studying microbial N2O production processes in N2O hotspots in permafrost peatlands, we identified denitrification as the dominant source of N2O in these surfaces.
Christian Rödenbeck, Tim DeVries, Judith Hauck, Corinne Le Quéré, and Ralph F. Keeling
Biogeosciences, 19, 2627–2652,Short summary
The ocean is an important part of the global carbon cycle, taking up about a quarter of the anthropogenic CO2 emitted by burning of fossil fuels and thus slowing down climate change. However, the CO2 uptake by the ocean is, in turn, affected by variability and trends in climate. Here we use carbon measurements in the surface ocean to quantify the response of the oceanic CO2 exchange to environmental conditions and discuss possible mechanisms underlying this response.
Lutz Beckebanze, Benjamin Reade Kreps Runkle, Josefine Walz, Christian Wille, David Holl, Manuel Helbig, Julia Boike, Torsten Sachs, and Lars Kutzbach
Revised manuscript accepted for BGShort summary
In this study, we present observations of lateral and vertical carbon fluxes from a permafrost-affected study site in the Russian Arctic. From this dataset we estimate the net ecosystem carbon balance for this study site. We show that lateral carbon export has a low impact on the net ecosystem carbon balance during the complete study period (3 months). Nevertheless, our results also show that lateral carbon export can exceed vertical carbon uptake at the beginning of the growing season.
Shuang Ma, Lifen Jiang, Rachel M. Wilson, Jeff P. Chanton, Scott Bridgham, Shuli Niu, Colleen M. Iversen, Avni Malhotra, Jiang Jiang, Xingjie Lu, Yuanyuan Huang, Jason Keller, Xiaofeng Xu, Daniel M. Ricciuto, Paul J. Hanson, and Yiqi Luo
Biogeosciences, 19, 2245–2262,Short summary
The relative ratio of wetland methane (CH4) emission pathways determines how much CH4 is oxidized before leaving the soil. We found an ebullition modeling approach that has a better performance in deep layer pore water CH4 concentration. We suggest using this approach in land surface models to accurately represent CH4 emission dynamics and response to climate change. Our results also highlight that both CH4 flux and belowground concentration data are important to constrain model parameters.
Shahar Baram, Asher Bar-Tal, Alon Gal, Shmulik P. Friedman, and David Russo
Static chambers are the most common tool used to measure greenhouse gas fluxes. We tested the impact of such chambers on N2O emissions in drip-irrigation. Field measurements and 3-D simulations show that the camber’s base drastically affects the water and nutrient distribution in the soil and hence the measured GHG fluxes. A nomogram is suggested to determine the optimal diameter of a cylindrical chamber that ensures minimal disturbance.
Mika Korkiakoski, Tiia Määttä, Krista Peltoniemi, Timo Penttilä, and Annalea Lohila
Biogeosciences, 19, 2025–2041,Short summary
We measured CH4 fluxes and production and oxidation potentials from irrigated and non-irrigated podzolic soil in a boreal forest. CH4 sink was smaller at the irrigated site but did not cause CH4 emission, with one exception. We also showed that under laboratory conditions, not only wet conditions, but also fresh carbon, are needed to make podzolic soil into a CH4 source. Our study provides important data for improving the process models describing the upland soil CH4 dynamics.
Sarah Shakil, Suzanne E. Tank, Jorien E. Vonk, and Scott Zolkos
Biogeosciences, 19, 1871–1890,Short summary
Permafrost thaw-driven landslides in the western Arctic are increasing organic carbon delivered to headwaters of drainage networks in the western Canadian Arctic by orders of magnitude. Through a series of laboratory experiments, we show that less than 10 % of this organic carbon is likely to be mineralized to greenhouse gases during transport in these networks. Rather most of the organic carbon is likely destined for burial and sequestration for centuries to millennia.
Janne Rinne, Patryk Łakomiec, Patrik Vestin, Joel D. White, Per Weslien, Julia Kelly, Natascha Kljun, Lena Ström, and Leif Klemedtsson
Preprint under review for BGShort summary
The study uses stable isotope 13C of carbon in methane to investigate the origins of spatial and temporal variation of methane emitted by a temperate wetland ecosystem. The results indicate that methane production is more important for spatial variation than methane consumption by micro-organisms. Temporal variation in seasonal timescale is most likely affected by more than one driver simultaneously.
Wolfgang Fischer, Christoph K. Thomas, Nikita Zimov, and Mathias Göckede
Biogeosciences, 19, 1611–1633,Short summary
Arctic permafrost ecosystems may release large amounts of carbon under warmer future climates and may therefore accelerate global climate change. Our study investigated how long-term grazing by large animals influenced ecosystem characteristics and carbon budgets at a Siberian permafrost site. Our results demonstrate that such management can contribute to stabilizing ecosystems to keep carbon in the ground, particularly through drying soils and reducing methane emissions.
Dong-Gill Kim, Ben Bond-Lamberty, Youngryel Ryu, Bumsuk Seo, and Dario Papale
Biogeosciences, 19, 1435–1450,Short summary
As carbon (C) and greenhouse gas (GHG) research has adopted appropriate technology and approach (AT&A), low-cost instruments, open-source software, and participatory research and their results were well accepted by scientific communities. In terms of cost, feasibility, and performance, the integration of low-cost and low-technology, participatory and networking-based research approaches can be AT&A for enhancing C and GHG research in developing countries.
Lutz Beckebanze, Zoé Rehder, David Holl, Christian Wille, Charlotta Mirbach, and Lars Kutzbach
Biogeosciences, 19, 1225–1244,Short summary
Arctic permafrost landscapes feature many water bodies. In contrast to the terrestrial parts of the landscape, the water bodies release carbon to the atmosphere. We compare carbon dioxide and methane fluxes from small water bodies to the surrounding tundra and find not accounting for the carbon dioxide emissions leads to an overestimation of the tundra uptake by 11 %. Consequently, changes in hydrology and water body distribution may substantially impact the overall carbon budget of the Arctic.
Brian Scott, Andrew H. Baldwin, and Stephanie A. Yarwood
Biogeosciences, 19, 1151–1164,Short summary
Carbon dioxide and methane contribute to global warming. What can we do? We can build wetlands: they store carbon dioxide and should cause global cooling. But when first built they produce excess methane. Eventually built wetlands will cause cooling, but it may take decades or even centuries. How we build wetlands matters. We show that a common practice, using organic matter, such as manure, can make a big difference whether or not the wetlands we build start global cooling within our lifetime.
Jan Knappe, Celia Somlai, and Laurence W. Gill
Biogeosciences, 19, 1067–1085,Short summary
Two domestic on-site wastewater treatment systems have been monitored for greenhouse gas (carbon dioxide, methane and nitrous oxide) emissions coming from the process units, soil and vent pipes. This has enabled the net greenhouse gas per person to be quantified for the first time, as well as the impact of pre-treatment on the effluent before being discharged to soil. These decentralised wastewater treatment systems serve approx. 20 % of the population in both Europe and the United States.
Yanan Zhao, Dennis Booge, Christa A. Marandino, Cathleen Schlundt, Astrid Bracher, Elliot L. Atlas, Jonathan Williams, and Hermann W. Bange
Biogeosciences, 19, 701–714,Short summary
We present here, for the first time, simultaneously measured dimethylsulfide (DMS) seawater concentrations and DMS atmospheric mole fractions from the Peruvian upwelling region during two cruises in December 2012 and October 2015. Our results indicate low oceanic DMS concentrations and atmospheric DMS molar fractions in surface waters and the atmosphere, respectively. In addition, the Peruvian upwelling region was identified as an insignificant source of DMS emissions during both periods.
Kukka-Maaria Kohonen, Roderick Dewar, Gianluca Tramontana, Aleksanteri Mauranen, Pasi Kolari, Linda M. J. Kooijmans, Dario Papale, Timo Vesala, and Ivan Mammarella
Revised manuscript accepted for BGShort summary
Four different methods for quantifying photosynthesis (GPP) at ecosystem scale were tested, of which two are based on carbon dioxide (CO2) and two on carbonyl sulfide (COS) flux measurements. CO2-based methods are traditional partitioning and a new method using machine learning. We introduce a novel method for calculating GPP from COS fluxes, with potentially better applicability than the former methods. Both COS-based methods gave on average higher GPP estimates than the CO2-based estimates.
Alexander J. Turner, Philipp Köhler, Troy S. Magney, Christian Frankenberg, Inez Fung, and Ronald C. Cohen
Biogeosciences, 18, 6579–6588,Short summary
This work builds a high-resolution estimate (500 m) of gross primary productivity (GPP) over the US using satellite measurements of solar-induced chlorophyll fluorescence (SIF) from the TROPOspheric Monitoring Instrument (TROPOMI) between 2018 and 2020. We identify ecosystem-specific scaling factors for estimating gross primary productivity (GPP) from TROPOMI SIF. Extreme precipitation events drive four regional GPP anomalies that account for 28 % of year-to-year GPP differences across the US.
Paul Laris, Moussa Koné, Fadiala Dembélé, Christine M. Rodrigue, Lilian Yang, Rebecca Jacobs, and Quincy Laris
Biogeosciences, 18, 6229–6244,Short summary
Savanna fires play a key role in the global carbon cycle because they release methane. Although it burns the most, there are few studies from West Africa. We conducted 36 experimental fires according to local practice to collect smoke samples. We found that fires set early in the season had higher methane emissions than those set later, and head fires had double the emissions of backfires. We conclude policies to reduce emissions will not have the desired effects if fire type is not considered.
Johan H. Scheller, Mikhail Mastepanov, Hanne H. Christiansen, and Torben R. Christensen
Biogeosciences, 18, 6093–6114,Short summary
Our study presents a time series of methane emissions in a high-Arctic-tundra landscape over 14 summers, which shows large variations between years. The methane emissions from the valley are expected to more than double in the late 21st century. This warming increases permafrost thaw, which could increase surface erosion in the valley. Increased erosion could offset some of the rise in methane fluxes from the valley, but this would require large-scale impacts on vegetated surfaces.
Patryk Łakomiec, Jutta Holst, Thomas Friborg, Patrick Crill, Niklas Rakos, Natascha Kljun, Per-Ola Olsson, Lars Eklundh, Andreas Persson, and Janne Rinne
Biogeosciences, 18, 5811–5830,Short summary
Methane emission from the subarctic mire with heterogeneous permafrost status was measured for the years 2014–2016. Lower methane emission was measured from the palsa mire sector while the thawing wet sector emitted more. Both sectors have a similar annual pattern with a gentle rise during spring and a decrease during autumn. The highest emission was observed in the late summer. Winter emissions were positive during the measurement period and have a significant impact on the annual budgets.
Balázs Grosz, Reinhard Well, Rene Dechow, Jan Reent Köster, Mohammad Ibrahim Khalil, Simone Merl, Andreas Rode, Bianca Ziehmer, Amanda Matson, and Hongxing He
Biogeosciences, 18, 5681–5697,Short summary
To assure quality predictions biogeochemical models must be current. We use data measured using novel incubation methods to test the denitrification sub-modules of three models. We aim to identify limitations in the denitrification modeling to inform next steps for development. Several areas are identified, most urgently improved denitrification control parameters and further testing with high-temporal-resolution datasets. Addressing these would significantly improve denitrification modeling.
Sarah Waldo, Jake J. Beaulieu, William Barnett, D. Adam Balz, Michael J. Vanni, Tanner Williamson, and John T. Walker
Biogeosciences, 18, 5291–5311,Short summary
Human-made reservoirs impact the carbon cycle. In particular, the breakdown of organic matter in reservoir sediments can result in large emissions of greenhouse gases (especially methane) to the atmosphere. This study takes an intensive look at the patterns in greenhouse gas emissions from a single reservoir in Ohio (United States) and the role of water temperature, precipitation, and algal blooms in emissions. We saw a "spring burst" of elevated emissions that challenged our assumptions.
Xinyu Liu, Xixi Lu, Ruihong Yu, Heyang Sun, Hao Xue, Zhen Qi, Zhengxu Cao, Zhuangzhuang Zhang, and Tingxi Liu
Biogeosciences, 18, 4855–4872,Short summary
Gradual riparian wetland drying is increasingly sensitive to global warming and contributes to climate change. We analyzed the emissions of CO2, CH4, and N2O from riparian wetlands in the Xilin River basin to understand the role of these ecosystems in greenhouse gas emissions. Our study showed that anthropogenic activities have extensively changed the hydrological characteristics of the riparian wetlands and might accelerate carbon loss, which could further affect greenhouse gas emissions.
Zhaohui Chen, Parvadha Suntharalingam, Andrew J. Watson, Ute Schuster, Jiang Zhu, and Ning Zeng
Biogeosciences, 18, 4549–4570,Short summary
As the global temperature continues to increase, carbon dioxide (CO2) is a major driver of this global warming. The increased CO2 is mainly caused by emissions from fossil fuel use and land use. At the same time, the ocean is a significant sink in the carbon cycle. The North Atlantic is a critical ocean region in reducing CO2 concentration. We estimate the CO2 uptake in this region based on a carbon inverse system and atmospheric CO2 observations.
Sirwan Yamulki, Jack Forster, Georgios Xenakis, Adam Ash, Jacqui Brunt, Mike Perks, and James I. L. Morison
Biogeosciences, 18, 4227–4241,Short summary
The effect of clear-felling on soil greenhouse gas (GHG) fluxes was assessed in a Sitka spruce forest. Measurements over 4 years showed that CO2, CH4, and N2O fluxes responded differently to clear-felling due to significant changes in soil biotic and abiotic factors and showed large variations between years. Over 3 years since felling, the soil GHG flux was reduced by 45% due to a much larger reduction in CO2 efflux than increases in N2O (up to 20%) and CH4 (changed from sink to source) fluxes.
Stefan Theodorus Johannes Weideveld, Weier Liu, Merit van den Berg, Leon Peter Maria Lamers, and Christian Fritz
Biogeosciences, 18, 3881–3902,Short summary
Raising the groundwater table (GWT) trough subsoil irrigation does not lead to a reduction of carbon emissions from drained peat meadows, even though there was a clear increase in the GWT during summer. Most likely, the largest part of the peat oxidation takes place in the top 70 cm of the soil, which stays above the GWT with the use of subsoil irrigation. We conclude that the use of subsoil irrigation is ineffective as a mitigation measure to sufficiently lower peat oxidation rates.
Yanming Gong, Ping Yue, Kaihui Li, Anwar Mohammat, and Yanyan Liu
Biogeosciences, 18, 3529–3537,Short summary
At present, data on the influence of asymmetric warming on the GHG flux on a temporal scale are scarce. GHG fluxes were measured using static chambers and a gas chromatograph. Our study showed that the effect of seasonally asymmetrical warming on CO2 flux was obvious, with the GHG flux being able to adapt to continuous warming. Warming in the non-growing season increased the temperature dependence of GHG flux.
Hella van Asperen, João Rafael Alves-Oliveira, Thorsten Warneke, Bruce Forsberg, Alessandro Carioca de Araújo, and Justus Notholt
Biogeosciences, 18, 2609–2625,Short summary
Termites are insects that are highly abundant in tropical ecosystems. It is known that termites emit CH4, an important greenhouse gas, but their absolute emission remains uncertain. In the Amazon rainforest, we measured CH4 emissions from termite nests and groups of termites. In addition, we tested a fast and non-destructive field method to estimate termite nest colony size. We found that termites play a significant role in an ecosystem's CH4 budget and probably emit more than currently assumed.
Genevieve L. Noyce and J. Patrick Megonigal
Biogeosciences, 18, 2449–2463,Short summary
Methane (CH4) is a potent greenhouse gas that contributes to global radiative forcing. A mechanistic understanding of how wetland CH4 cycling will respond to global warming is crucial for improving prognostic models. We present results from the first 4 years of a novel whole-ecosystem warming experiment in a coastal wetland, showing that warming increases CH4 emissions and identifying four potential mechanisms that can be added to future modeling efforts.
Yanan Zhao, Cathleen Schlundt, Dennis Booge, and Hermann W. Bange
Biogeosciences, 18, 2161–2179,Short summary
We present a unique and comprehensive time-series study of biogenic sulfur compounds in the southwestern Baltic Sea, from 2009 to 2018. Dimethyl sulfide is one of the key players regulating global climate change, as well as dimethylsulfoniopropionate and dimethyl sulfoxide. Their decadal trends did not follow increasing temperature but followed some algae group abundances at the Boknis Eck Time Series Station.
Ingeborg Bussmann, Irina Fedorova, Bennet Juhls, Pier Paul Overduin, and Matthias Winkel
Biogeosciences, 18, 2047–2061,Short summary
Arctic rivers, lakes, and bays are affected by a warming climate. We measured the amount and consumption of methane in waters from Siberia under ice cover and in open water. In the lake, methane concentrations under ice cover were much higher than in summer, and methane consumption was highest. The ice cover leads to higher methane concentration under ice. In a warmer Arctic, there will be more time with open water when methane is consumed by bacteria, and less methane will escape into the air.
Elisa Vainio, Olli Peltola, Ville Kasurinen, Antti-Jussi Kieloaho, Eeva-Stiina Tuittila, and Mari Pihlatie
Biogeosciences, 18, 2003–2025,Short summary
We studied forest floor methane exchange over an area of 10 ha in a boreal pine forest. The results demonstrate high spatial variability in soil moisture and consequently in the methane flux. We detected wet patches emitting high amounts of methane in the early summer; however, these patches turned to methane uptake in the autumn. We concluded that the small-scale spatial variability of the boreal forest methane flux highlights the importance of soil chamber placement in similar studies.
Matthias Koschorreck, Yves T. Prairie, Jihyeon Kim, and Rafael Marcé
Biogeosciences, 18, 1619–1627,Short summary
The concentration of carbon dioxide (CO2) in water samples is often measured using a gas chromatograph. Depending on the chemical composition of the water, this method can produce wrong results. We quantified the possible error and how it depends on water composition and the analytical procedure. We propose a method to correct wrong results by additionally analysing alkalinity in the samples. We provide an easily usable computer code to perform the correction calculations.
Julia Drewer, Melissa M. Leduning, Robert I. Griffiths, Tim Goodall, Peter E. Levy, Nicholas Cowan, Edward Comynn-Platt, Garry Hayman, Justin Sentian, Noreen Majalap, and Ute M. Skiba
Biogeosciences, 18, 1559–1575,Short summary
In Southeast Asia, oil palm plantations have largely replaced tropical forests. The impact of this shift in land use on greenhouse gas fluxes and soil microbial communities remains uncertain. We have found emission rates of the potent greenhouse gas nitrous oxide on mineral soil to be higher from oil palm plantations than logged forest over a 2-year study and concluded that emissions have increased over the last 42 years in Sabah, with the proportion of emissions from plantations increasing.
Lutz Merbold, Charlotte Decock, Werner Eugster, Kathrin Fuchs, Benjamin Wolf, Nina Buchmann, and Lukas Hörtnagl
Biogeosciences, 18, 1481–1498,Short summary
Our study investigated the exchange of the three major greenhouse gases (GHGs) over a temperate grassland prior to and after restoration through tillage in central Switzerland. Our results show that irregular management events, such as tillage, have considerable effects on GHG emissions in the year of tillage while leading to enhanced carbon uptake and similar nitrogen losses via nitrous oxide in the years following tillage to those observed prior to tillage.
Roland Vernooij, Marcos Giongo, Marco Assis Borges, Máximo Menezes Costa, Ana Carolina Sena Barradas, and Guido R. van der Werf
Biogeosciences, 18, 1375–1393,Short summary
We used drones to measure greenhouse gas emission factors from fires in the Brazilian Cerrado. We compared early-dry-season management fires and late-dry-season fires to determine if fire management can be a tool for abating emissions. Although we found some evidence of increased CO and CH4 emission factors, the seasonal effect was smaller than that found in previous studies. For N2O, the third most important greenhouse gas, we found opposite trends in grass- and shrub-dominated areas.
Filippo Vingiani, Nicola Durighetto, Marcus Klaus, Jakob Schelker, Thierry Labasque, and Gianluca Botter
Biogeosciences, 18, 1223–1240,Short summary
Flexible foil chamber design and the anchored deployment might be useful techniques to enhance the robustness and the accuracy of CO2 measurements in low-order streams. Moreover, the study demonstrates the value of analytical and numerical techniques for the estimation of gas exchange velocities. These results may contribute to the development of novel procedures for chamber data analysis which might improve the robustness and reliability of chamber-based CO2 measurements in first-order streams.
Lauri Heiskanen, Juha-Pekka Tuovinen, Aleksi Räsänen, Tarmo Virtanen, Sari Juutinen, Annalea Lohila, Timo Penttilä, Maiju Linkosalmi, Juha Mikola, Tuomas Laurila, and Mika Aurela
Biogeosciences, 18, 873–896,Short summary
We studied ecosystem- and plant-community-level carbon (C) exchange between subarctic mire and the atmosphere during 2017–2018. We found strong spatial variation in CO2 and CH4 dynamics between the main plant communities. The earlier onset of growing season in 2018 strengthened the CO2 sink of the ecosystem, but this gain was counterbalanced by a later drought period. Variation in water table level, soil temperature and vegetation explained most of the variation in ecosystem-level C exchange.
Sudhanshu Pandey, Sander Houweling, Alba Lorente, Tobias Borsdorff, Maria Tsivlidou, A. Anthony Bloom, Benjamin Poulter, Zhen Zhang, and Ilse Aben
Biogeosciences, 18, 557–572,Short summary
We use atmospheric methane observations from the novel TROPOspheric Monitoring Instrument (TROPOMI; Sentinel-5p) to estimate methane emissions from South Sudan's wetlands. Our emission estimates are an order of magnitude larger than the estimate of process-based wetland models. We find that this underestimation by the models is likely due to their misrepresentation of the wetlands' inundation extent and temperature dependences.
Paula Alejandra Lamprea Pineda, Marijn Bauters, Hans Verbeeck, Selene Baez, Matti Barthel, Samuel Bodé, and Pascal Boeckx
Biogeosciences, 18, 413–421,Short summary
Tropical forest soils are an important source and sink of greenhouse gases (GHGs) with tropical montane forests having been poorly studied. In this pilot study, we explored soil fluxes of CO2, CH4, and N2O in an Ecuadorian neotropical montane forest, where a net consumption of N2O at higher altitudes was observed. Our results highlight the importance of short-term variations in N2O and provide arguments and insights for future, more detailed studies on GHG fluxes from montane forest soils.
Bruna R. F. Oliveira, Carsten Schaller, J. Jacob Keizer, and Thomas Foken
Biogeosciences, 18, 285–302,Short summary
Forest fires have a significant impact on carbon dioxide emissions. The present study from a pine forest in Portugal is one of the few where measurements of CO2 fluxes were started immediately (1.5 months) after the forest fire. Carbon dioxide emissions were linked to soil humidity. Therefore, they started after the beginning of the rainfall in autumn. Due to the beginning of vegetation, the site was already a carbon dioxide sink the following year.
Hui Zhang, Eeva-Stiina Tuittila, Aino Korrensalo, Aleksi Räsänen, Tarmo Virtanen, Mika Aurela, Timo Penttilä, Tuomas Laurila, Stephanie Gerin, Viivi Lindholm, and Annalea Lohila
Biogeosciences, 17, 6247–6270,Short summary
We studied the impact of a stream on peatland microhabitats and CH4 emissions in a northern boreal fen. We found that there were higher water levels, lower peat temperatures, and greater oxygen concentrations close to the stream; these supported the highest biomass production but resulted in the lowest CH4 emissions. Further from the stream, the conditions were drier and CH4 emissions were also low. CH4 emissions were highest at an intermediate distance from the stream.
Simon Baumgartner, Matti Barthel, Travis William Drake, Marijn Bauters, Isaac Ahanamungu Makelele, John Kalume Mugula, Laura Summerauer, Nora Gallarotti, Landry Cizungu Ntaboba, Kristof Van Oost, Pascal Boeckx, Sebastian Doetterl, Roland Anton Werner, and Johan Six
Biogeosciences, 17, 6207–6218,Short summary
Soil respiration is an important carbon flux and key process determining the net ecosystem production of terrestrial ecosystems. The Congo Basin lacks studies quantifying carbon fluxes. We measured soil CO2 fluxes from different forest types in the Congo Basin and were able to show that, even though soil CO2 fluxes are similarly high in lowland and montane forests, the drivers were different: soil moisture in montane forests and C availability in the lowland forests.
Bettina K. Gier, Michael Buchwitz, Maximilian Reuter, Peter M. Cox, Pierre Friedlingstein, and Veronika Eyring
Biogeosciences, 17, 6115–6144,Short summary
Models from Coupled Model Intercomparison Project (CMIP) phases 5 and 6 are compared to a satellite data product of column-averaged CO2 mole fractions (XCO2). The previously believed discrepancy of the negative trend in seasonal cycle amplitude in the satellite product, which is not seen in in situ data nor in the models, is attributed to a sampling characteristic. Furthermore, CMIP6 models are shown to have made progress in reproducing the observed XCO2 time series compared to CMIP5.
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,Short summary
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.
Najeeb Al-Amin Iddris, Marife D. Corre, Martin Yemefack, Oliver van Straaten, and Edzo Veldkamp
Biogeosciences, 17, 5377–5397,Short summary
We quantified the changes in stem and soil nitrous oxide (N2O) fluxes with forest conversion to cacao agroforestry in the Congo Basin, Cameroon. All forest and cacao trees consistently emitted N2O, contributing 8–38 % of the total (soil and stem) emissions. Forest conversion to extensively managed (>–20 years old) cacao agroforestry had no effect on stem and soil N2O fluxes. Our results highlight the importance of including tree-mediated fluxes in the ecosystem-level N2O budget.
Cédric Morana, Steven Bouillon, Vimac Nolla-Ardèvol, Fleur A. E. Roland, William Okello, Jean-Pierre Descy, Angela Nankabirwa, Erina Nabafu, Dirk Springael, and Alberto V. Borges
Biogeosciences, 17, 5209–5221,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.
Åberg, J. and Wallin, B.: Evaluating a fast headspace method for measuring DIC and subsequent calculation of pCO2 in freshwater systems, Inl. Waters, 4, 157–166, https://doi.org/10.5268/IW-4.2.694, 2014.
Abril, G. and Borges, A. V.: Ideas and perspectives: Carbon leaks from flooded land: do we need to replumb the inland water active pipe?, Biogeosciences, 16, 769–784, https://doi.org/10.5194/bg-16-769-2019, 2019.
Abril, G., Martinez, J. M., Artigas, L. F., Moreira-Turcq, P., Benedetti, M. F., Vidal, L., Meziane, T., Kim, J. H., Bernardes, M. C., Savoye, N., Deborde, J., Souza, E. L., Albéric, P., Landim De Souza, M. F., and Roland, F.: Amazon River carbon dioxide outgassing fuelled by wetlands, Nature, 505, 395–398, https://doi.org/10.1038/nature12797, 2014.
Abril, G., Bouillon, S., Darchambeau, F., Teodoru, C. R., Marwick, T. R., Tamooh, F., Ochieng Omengo, F., Geeraert, N., Deirmendjian, L., Polsenaere, P., and Borges, A. V.: Technical Note: Large overestimation of pCO2 calculated from pH and alkalinity in acidic, organic-rich freshwaters, Biogeosciences, 12, 67–78, https://doi.org/10.5194/bg-12-67-2015, 2015.
Alin, S. R., Rasera, M. D. F. F. L., Salimon, C. I., Richey, J. E., Holtgrieve, G. W., Krusche, A. V., and Snidvongs, A.: Physical controls on carbon dioxide transfer velocity and flux in low-gradient river systems and implications for regional carbon budgets, J. Geophys. Res.-Biogeo., 116, G01009, https://doi.org/10.1029/2010JG001398, 2011.
Allen, G. H. and Pavelsky, T. M.: Global extent of rivers and streams, Science, 361, 585–588, https://doi.org/10.1126/science.aat0636, 2018.
Amiotte Suchet, P., Probst, J., and Ludwig, W.: Worldwide distribution of continental rock lithology: Implications for the atmospheric/soil CO2 uptake by continental weathering and alkalinity river transport to the oceans, Global Biogeochem. Cy., 17, 1038, https://doi.org/10.1029/2002GB001891, 2003.
Audry, S., Bessa, H. A., Bedimo, J.-P. B., Boeglin, J.-L., Boithias, L., Braun, J.-J., Dupré, B., Faucheux, M., Lagane, C., Maréchal, J.-C., Ndam-Ngoupayou, J. R., Nnomo, B. N., Nlozoa, J., Ntonga, J.-C., Ribolzi, O., Riotte, J., Rochelle-Newall, E., and Ruiz, L.: The Multiscale TROPIcal CatchmentS critical zone observatory M-TROPICS dataset I: The Nyong River Basin, Cameroon, Hydrol. Process., 35, e14138, https://doi.org/10.1002/HYP.14138, 2021.
Boeglin, J.-L., Ndam, J.-R., and Braun, J.-J.: Composition of the different reservoir waters in a tropical humid area: example of the Nsimi catchment (Southern Cameroon), J. African Earth Sci., 37, 103–110, 2003.
Boeglin, J., Probst, J., Ndam-Ngoupayou, J., Nyeck, B., Etcheber, H., Mortatti, J., and Braun, J.: Soil carbon stock and river carbon fluxes in humid tropical environments: the Nyong river basin (south Cameroon), in: Soil Erosion and Carbon Dynamics, Adv. Soil Sci., CRC Press Boca Raton, Fla., 275–288, 2005.
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We monitor the spatio-temporal variability of organic and inorganic carbon (C) species in the tropical Nyong River (Cameroon), across groundwater and increasing stream orders. We show the significant contribution of wetland as a C source for tropical rivers. Thus, ignoring the river–wetland connectivity might lead to the misrepresentation of C dynamics in tropical watersheds. Finally, total fluvial carbon losses might offset ~10 % of the net C sink estimated for the whole Nyong watershed.
We monitor the spatio-temporal variability of organic and inorganic carbon (C) species in the...