Articles | Volume 12, issue 4
https://doi.org/10.5194/bg-12-1073-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/bg-12-1073-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Sources and export of particle-borne organic matter during a monsoon flood in a catchment of northern Laos
E. Gourdin
CORRESPONDING AUTHOR
Laboratoire des Sciences du Climat et de l'Environnement (LSCE), UMR 8212 (CEA-CNRS-UVSQ-IPSL), Domaine du CNRS, avenue de la Terrasse, 91198 Gif-sur-Yvette CEDEX, France
S. Huon
Université Pierre et Marie Curie (UPMC), UMR 7618 iEES (UPMC-CNRS-IRD-INRA-Université Paris 7-UPEC), case 120, 4 place Jussieu, 75252 Paris CEDEX 05, France
O. Evrard
Laboratoire des Sciences du Climat et de l'Environnement (LSCE), UMR 8212 (CEA-CNRS-UVSQ-IPSL), Domaine du CNRS, avenue de la Terrasse, 91198 Gif-sur-Yvette CEDEX, France
O. Ribolzi
IRD, Géosciences Environnement Toulouse (GET), UMR 5563 (CNRS-UPS-IRD), 14 avenue Edouard Belin, 31400 Toulouse, France
T. Bariac
CNRS, UMR 7618 iEES (UPMC-CNRS-IRD-INRA-Université Paris 7-UPEC), campus INRA – AgroParisTech, Bâtiment EGER, 78550 Thiverval-Grignon, France
O. Sengtaheuanghoung
Department of Agriculture Land Management (DALam), P.O. Box 4199, Ban Nogviengkham, Xaythany District, Vientiane, Laos
S. Ayrault
Laboratoire des Sciences du Climat et de l'Environnement (LSCE), UMR 8212 (CEA-CNRS-UVSQ-IPSL), Domaine du CNRS, avenue de la Terrasse, 91198 Gif-sur-Yvette CEDEX, France
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Gerald Dicen, Floriane Guillevic, Surya Gupta, Pierre-Alexis Chaboche, Katrin Meusburger, Pierre Sabatier, Olivier Evrard, and Christine Alewell
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2024-509, https://doi.org/10.5194/essd-2024-509, 2024
Preprint under review for ESSD
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Fallout radionuclides such as 137Cs and 239+240Pu are considered as critical tools in various environmental research. Here, we compiled reference soil data on these fallout radionuclides from the literature to build a comprehensive database. Using this database, we determined the distribution and sources of 137Cs and 239+240Pu. We also demonstrated how the database can be used to identify the environmental factors that influence their distribution using a machine-learning algorithm.
Thomas Chalaux-Clergue, Rémi Bizeul, Pedro V. G. Batista, Núria Martínez-Carreras, J. Patrick Laceby, and Olivier Evrard
SOIL, 10, 109–138, https://doi.org/10.5194/soil-10-109-2024, https://doi.org/10.5194/soil-10-109-2024, 2024
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Sediment source fingerprinting is a relevant tool to support soil conservation and watershed management in the context of accelerated soil erosion. To quantify sediment source contribution, it requires the selection of relevant tracers. We compared the three-step method and the consensus method and found very contrasted trends. The divergences between virtual mixtures and sample prediction ranges highlight that virtual mixture statistics are not directly transferable to actual samples.
Anthony Foucher, Sergio Morera, Michael Sanchez, Jhon Orrillo, and Olivier Evrard
Hydrol. Earth Syst. Sci., 27, 3191–3204, https://doi.org/10.5194/hess-27-3191-2023, https://doi.org/10.5194/hess-27-3191-2023, 2023
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The current research investigated, as a representative study case, the sediment accumulated in the Poechos Reservoir (located on the west coast of northern Peru) for retrospectively reconstructing the impact on sediment dynamics (1978–2019) of extreme phases of the El Niño–Southern Oscillation, land cover changes after humid periods and agricultural expansion along the riverine system.
Olivier Evrard, Thomas Chalaux-Clergue, Pierre-Alexis Chaboche, Yoshifumi Wakiyama, and Yves Thiry
SOIL, 9, 479–497, https://doi.org/10.5194/soil-9-479-2023, https://doi.org/10.5194/soil-9-479-2023, 2023
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Twelve years after the nuclear accident that occurred in Fukushima in March 2011, radioactive contamination remains a major concern in north-eastern Japan. The Japanese authorities completed an unprecedented decontamination programme. The central objective was to not expose local inhabitants to excessive radioactive doses. At the onset of the full reopening of the Difficult-to-Return Zone in 2023, the current review provides an update of a previous synthesis published in 2019.
Marie Dumont, Simon Gascoin, Marion Réveillet, Didier Voisin, François Tuzet, Laurent Arnaud, Mylène Bonnefoy, Montse Bacardit Peñarroya, Carlo Carmagnola, Alexandre Deguine, Aurélie Diacre, Lukas Dürr, Olivier Evrard, Firmin Fontaine, Amaury Frankl, Mathieu Fructus, Laure Gandois, Isabelle Gouttevin, Abdelfateh Gherab, Pascal Hagenmuller, Sophia Hansson, Hervé Herbin, Béatrice Josse, Bruno Jourdain, Irene Lefevre, Gaël Le Roux, Quentin Libois, Lucie Liger, Samuel Morin, Denis Petitprez, Alvaro Robledano, Martin Schneebeli, Pascal Salze, Delphine Six, Emmanuel Thibert, Jürg Trachsel, Matthieu Vernay, Léo Viallon-Galinier, and Céline Voiron
Earth Syst. Sci. Data, 15, 3075–3094, https://doi.org/10.5194/essd-15-3075-2023, https://doi.org/10.5194/essd-15-3075-2023, 2023
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Saharan dust outbreaks have profound effects on ecosystems, climate, health, and the cryosphere, but the spatial deposition pattern of Saharan dust is poorly known. Following the extreme dust deposition event of February 2021 across Europe, a citizen science campaign was launched to sample dust on snow over the Pyrenees and the European Alps. This campaign triggered wide interest and over 100 samples. The samples revealed the high variability of the dust properties within a single event.
Laurie Boithias, Olivier Ribolzi, Emma Rochelle-Newall, Chanthanousone Thammahacksa, Paty Nakhle, Bounsamay Soulileuth, Anne Pando-Bahuon, Keooudone Latsachack, Norbert Silvera, Phabvilay Sounyafong, Khampaseuth Xayyathip, Rosalie Zimmermann, Sayaphet Rattanavong, Priscia Oliva, Thomas Pommier, Olivier Evrard, Sylvain Huon, Jean Causse, Thierry Henry-des-Tureaux, Oloth Sengtaheuanghoung, Nivong Sipaseuth, and Alain Pierret
Earth Syst. Sci. Data, 14, 2883–2894, https://doi.org/10.5194/essd-14-2883-2022, https://doi.org/10.5194/essd-14-2883-2022, 2022
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Fecal pathogens in surface waters may threaten human health, especially in developing countries. The Escherichia coli (E. coli) database is organized in three datasets and includes 1602 records from 31 sampling stations located within the Mekong River basin in Lao PDR. Data have been used to identify the drivers of E. coli dissemination across tropical catchments, including during floods. Data may be further used to interpret new variables or to map the health risk posed by fecal pathogens.
Virginie Sellier, Oldrich Navratil, John Patrick Laceby, Cédric Legout, Anthony Foucher, Michel Allenbach, Irène Lefèvre, and Olivier Evrard
SOIL, 7, 743–766, https://doi.org/10.5194/soil-7-743-2021, https://doi.org/10.5194/soil-7-743-2021, 2021
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Open-cast mining increases soil erosion and transfer of sediment in river systems. Providing a methodology to better understand the sediment dynamic of these catchments is essential to manage this pollution. In this study, different tracers such as elemental geochemistry or colour properties were tested to trace and quantify the mining source contributions to the sediment inputs in the Thio River catchment, one of the first areas exploited for nickel mining in New Caledonia (i.e. since 1880).
Anthony Foucher, Pierre-Alexis Chaboche, Pierre Sabatier, and Olivier Evrard
Earth Syst. Sci. Data, 13, 4951–4966, https://doi.org/10.5194/essd-13-4951-2021, https://doi.org/10.5194/essd-13-4951-2021, 2021
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Sediment archives provide a powerful and unique tool for reconstructing the trajectory and the resilience of terrestrial and aquatic ecosystems facing major environmental changes. Establishing an age depth–model is the first prerequisite of any paleo-investigation. This study synthesizes the distribution of two radionuclides classically used to this aim, providing a worldwide reference to help the scientific community reach a consensus for dating recent sedimentary archives.
Olivier Evrard, Caroline Chartin, J. Patrick Laceby, Yuichi Onda, Yoshifumi Wakiyama, Atsushi Nakao, Olivier Cerdan, Hugo Lepage, Hugo Jaegler, Rosalie Vandromme, Irène Lefèvre, and Philippe Bonté
Earth Syst. Sci. Data, 13, 2555–2560, https://doi.org/10.5194/essd-13-2555-2021, https://doi.org/10.5194/essd-13-2555-2021, 2021
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This dataset provides an original compilation of radioactive dose rates and artificial radionuclide activities in sediment deposited after floods in the rivers draining the main radioactive pollution plume in Fukushuma, Japan, between November
2011 and November 2020. In total, 782 sediment samples collected from 27 to 71 locations during 16 fieldwork campaigns were analysed. This provides a unique post-accidental dataset to better understand the environmental fate of radionuclides.
André-Marie Dendievel, Brice Mourier, Alexandra Coynel, Olivier Evrard, Pierre Labadie, Sophie Ayrault, Maxime Debret, Florence Koltalo, Yoann Copard, Quentin Faivre, Thomas Gardes, Sophia Vauclin, Hélène Budzinski, Cécile Grosbois, Thierry Winiarski, and Marc Desmet
Earth Syst. Sci. Data, 12, 1153–1170, https://doi.org/10.5194/essd-12-1153-2020, https://doi.org/10.5194/essd-12-1153-2020, 2020
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Polychlorinated biphenyl indicators (ΣPCBi) from sediment cores, bed and flood deposits, suspended particulate matter, and dredged sediments along the major French rivers (1945–2018) are compared with socio-hydrological drivers. ΣPCBi increased from 1945 to the 1990s due to urban and industrial emissions. It gradually decreased with the implementation of regulations. Specific ΣPCBi fluxes reveal the amount of PCB-polluted sediment transported by French rivers to European seas over 40 years.
Olivier Evrard, J. Patrick Laceby, and Atsushi Nakao
SOIL, 5, 333–350, https://doi.org/10.5194/soil-5-333-2019, https://doi.org/10.5194/soil-5-333-2019, 2019
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The Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident in March 2011 resulted in the contamination of Japanese landscapes with radioactive fallout. The objective of this review is to provide an overview of the decontamination strategies and their potential effectiveness in Japan. Overall, we believe it is important to synthesise the remediation lessons learnt following the FDNPP nuclear accident, which could be fundamental if radioactive fallout occurred somewhere on Earth in the future.
Guillaume Lacombe, Olivier Ribolzi, Anneke de Rouw, Alain Pierret, Keoudone Latsachak, Norbert Silvera, Rinh Pham Dinh, Didier Orange, Jean-Louis Janeau, Bounsamai Soulileuth, Henri Robain, Adrien Taccoen, Phouthamaly Sengphaathith, Emmanuel Mouche, Oloth Sengtaheuanghoung, Toan Tran Duc, and Christian Valentin
Hydrol. Earth Syst. Sci., 20, 2691–2704, https://doi.org/10.5194/hess-20-2691-2016, https://doi.org/10.5194/hess-20-2691-2016, 2016
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Laos and Vietnam have switched from net forest loss to net forest expansion between 1990 and 2015. Based on long-term field measurements of land use, river flows, and weather data, we demonstrate that forest expansion can have extreme, yet opposite, impacts on water resources, depending on how the newly established tree-based cover is managed. The conversion of annual crops to teak plantations in Laos or to naturally regrowing forests in Vietnam led to increased and decreased flows, respectively.
J. Patrick Laceby, Caroline Chartin, Olivier Evrard, Yuichi Onda, Laurent Garcia-Sanchez, and Olivier Cerdan
Hydrol. Earth Syst. Sci., 20, 2467–2482, https://doi.org/10.5194/hess-20-2467-2016, https://doi.org/10.5194/hess-20-2467-2016, 2016
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Characterizing rainfall erosivity in the Fukushima fallout-impacted region is important for predicting radiocesium behavior. The majority of rainfall (60 %) and rainfall erosivity (86 %) occurs between June and October. Tropical cyclones contribute 22 % of the precipitation though 44 % of the rainfall erosivity. Understanding the rainfall regime and the influence of tropical cyclones is important managing radiocesium transfers in contaminated catchments in the Fukushima prefecture.
H. Lepage, O. Evrard, Y. Onda, I. Lefèvre, J. P. Laceby, and S. Ayrault
SOIL Discuss., https://doi.org/10.5194/soild-1-401-2014, https://doi.org/10.5194/soild-1-401-2014, 2014
Revised manuscript not accepted
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Biogeosciences, 21, 3537–3550, https://doi.org/10.5194/bg-21-3537-2024, https://doi.org/10.5194/bg-21-3537-2024, 2024
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Biogeosciences, 21, 3093–3120, https://doi.org/10.5194/bg-21-3093-2024, https://doi.org/10.5194/bg-21-3093-2024, 2024
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EGUsphere, https://doi.org/10.5194/egusphere-2024-492, https://doi.org/10.5194/egusphere-2024-492, 2024
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Kirsi H. Keskitalo, Lisa Bröder, Tommaso Tesi, Paul J. Mann, Dirk J. Jong, Sergio Bulte Garcia, Anna Davydova, Sergei Davydov, Nikita Zimov, Negar Haghipour, Timothy I. Eglinton, and Jorien E. Vonk
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Riverine alkalinity in the silicate-dominated headwater catchment at subarctic Iskorasfjellet, northern Norway, was almost entirely derived from weathering of minor carbonate occurrences in the riparian zone. The uphill catchment appeared limited by insufficient contact time of weathering agents and weatherable material. Further, alkalinity increased with decreasing permafrost extent. Thus, with climate change, alkalinity generation is expected to increase in this permafrost-degrading landscape.
Jancoba Dorley, Joel Singley, Tim Covino, Kamini Singha, Michael Gooseff, David Van Horn, and Ricardo González-Pinzón
Biogeosciences, 20, 3353–3366, https://doi.org/10.5194/bg-20-3353-2023, https://doi.org/10.5194/bg-20-3353-2023, 2023
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We quantified how microbial respiration is controlled by discharge and the supply of C, N, and P in a stream. We ran two rounds of experiments adding a conservative tracer, an indicator of aerobic respiration, and nutrient treatments: a) N, b) N+C, c) N+P, and d) C+N+P. Microbial respiration remained similar between rounds and across nutrient treatments. This suggests that complex interactions between hydrology, resource supply, and biological community drive in-stream respiration.
Paolo Peruzzo, Matteo Cappozzo, Nicola Durighetto, and Gianluca Botter
Biogeosciences, 20, 3261–3271, https://doi.org/10.5194/bg-20-3261-2023, https://doi.org/10.5194/bg-20-3261-2023, 2023
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Small cascades greatly enhance mountain stream gas emissions through the turbulent energy dissipation rate and air bubbles entrained into the water. We numerically studied the local contribution of these mechanisms driving gas transfer velocity used to quantify the outgassing. The gas evasion is primarily due to bubbles concentrated in irregular spots of limited area. Consequently, the gas exchange velocity is scale-dependent and unpredictable, posing concerns about its use in similar scenarios.
Philipp Maurischat, Michael Seidel, Thorsten Dittmar, and Georg Guggenberger
Biogeosciences, 20, 3011–3026, https://doi.org/10.5194/bg-20-3011-2023, https://doi.org/10.5194/bg-20-3011-2023, 2023
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Production and consumption of organic matter (OM) on the Tibetan Plateau are important for this sensitive ecosystem. We investigated the chemical composition of dissolved organic matter and the most mobile fraction of OM in glaciers, wetlands, and groundwater as well as in the rivers and a large terminal lake. Our data show that the sources differ in the molecular composition of OM, that the stream is influenced by agriculture, and that the lake strongly changes the inflowing organic matter.
James C. Stegen, Vanessa A. Garayburu-Caruso, Robert E. Danczak, Amy E. Goldman, Lupita Renteria, Joshua M. Torgeson, and Jacqueline Hager
Biogeosciences, 20, 2857–2867, https://doi.org/10.5194/bg-20-2857-2023, https://doi.org/10.5194/bg-20-2857-2023, 2023
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Chemical reactions in river sediments influence how clean the water is and how much greenhouse gas comes out of a river. Our study investigates why some sediments have higher rates of chemical reactions than others. We find that to achieve high rates, sediments need to have two things: only a few different kinds of molecules, but a lot of them. This result spans about 80 rivers such that it could be a general rule, helpful for predicting the future of rivers and our planet.
Andrew L. Robison, Nicola Deluigi, Camille Rolland, Nicolas Manetti, and Tom Battin
Biogeosciences, 20, 2301–2316, https://doi.org/10.5194/bg-20-2301-2023, https://doi.org/10.5194/bg-20-2301-2023, 2023
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Climate change is affecting mountain ecosystems intensely, including the loss of glaciers and the uphill migration of plants. How these changes will affect the streams draining these landscapes is unclear. We sampled streams across a gradient of glacier and vegetation cover in Switzerland and found glacier loss reduced the carbon dioxide sink from weathering, while vegetation cover increased dissolved organic carbon in the stream. These changes are important to consider for mountains globally.
Olga Ogneva, Gesine Mollenhauer, Bennet Juhls, Tina Sanders, Juri Palmtag, Matthias Fuchs, Hendrik Grotheer, Paul J. Mann, and Jens Strauss
Biogeosciences, 20, 1423–1441, https://doi.org/10.5194/bg-20-1423-2023, https://doi.org/10.5194/bg-20-1423-2023, 2023
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Arctic warming accelerates permafrost thaw and release of terrestrial organic matter (OM) via rivers to the Arctic Ocean. We compared particulate organic carbon (POC), total suspended matter, and C isotopes (δ13C and Δ14C of POC) in the Lena delta and Lena River along a ~1600 km transect. We show that the Lena delta, as an interface between the Lena River and the Arctic Ocean, plays a crucial role in determining the qualitative and quantitative composition of OM discharged into the Arctic Ocean.
Weitian Ding, Urumu Tsunogai, Fumiko Nakagawa, Takashi Sambuichi, Masaaki Chiwa, Tamao Kasahara, and Ken'ichi Shinozuka
Biogeosciences, 20, 753–766, https://doi.org/10.5194/bg-20-753-2023, https://doi.org/10.5194/bg-20-753-2023, 2023
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By monitoring the concentration and Δ17O of stream nitrate in three forested streams, the new nitrogen saturation index of forested catchments (Matm/Datm ratio) was estimated. We found that (1) the unprocessed atmospheric nitrate in our studied forested stream (FK1 catchment) was the highest ever reported in forested streams; (2) the Matm/Datm ratio can be used as a robust index for evaluating nitrogen saturation in forested catchments as the Matm/Datm ratio is independent of the precipitation.
Kirstin Dähnke, Tina Sanders, Yoana Voynova, and Scott D. Wankel
Biogeosciences, 19, 5879–5891, https://doi.org/10.5194/bg-19-5879-2022, https://doi.org/10.5194/bg-19-5879-2022, 2022
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Nitrogen is an important macronutrient that fuels algal production in rivers and coastal regions. We investigated the production and removal of nitrogen-bearing compounds in the freshwater section of the tidal Elbe Estuary and found that particles in the water column are key for the production and removal of water column nitrate. Using a stable isotope approach, we pinpointed regions where additional removal of nitrate or input from sediments plays an important role in estuarine biogeochemistry.
Tamara Michaelis, Anja Wunderlich, Ömer K. Coskun, William Orsi, Thomas Baumann, and Florian Einsiedl
Biogeosciences, 19, 4551–4569, https://doi.org/10.5194/bg-19-4551-2022, https://doi.org/10.5194/bg-19-4551-2022, 2022
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The greenhouse gas methane (CH4) drives climate change. Microorganisms in river sediments produce CH4 when degrading organic matter, but the contribution of rivers to atmospheric CH4 concentrations is uncertain. To better understand riverine CH4 cycling, we measured concentration profiles of CH4 and relevant reactants that might influence the CH4 cycle. We found substantial CH4 production, especially in fine, organic-rich sediments during summer and signs of microbial CH4 consumption.
James C. Stegen, Sarah J. Fansler, Malak M. Tfaily, Vanessa A. Garayburu-Caruso, Amy E. Goldman, Robert E. Danczak, Rosalie K. Chu, Lupita Renteria, Jerry Tagestad, and Jason Toyoda
Biogeosciences, 19, 3099–3110, https://doi.org/10.5194/bg-19-3099-2022, https://doi.org/10.5194/bg-19-3099-2022, 2022
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Rivers are vital to Earth, and in rivers, organic matter (OM) is an energy source for microbes that make greenhouse gas and remove contaminants. Predicting Earth’s future requires understanding how and why river OM is transformed. Our results help meet this need. We found that the processes influencing OM transformations diverge between river water and riverbed sediments. This can be used to build new models for predicting the future of rivers and, in turn, the Earth system.
Alexandra Klemme, Tim Rixen, Denise Müller-Dum, Moritz Müller, Justus Notholt, and Thorsten Warneke
Biogeosciences, 19, 2855–2880, https://doi.org/10.5194/bg-19-2855-2022, https://doi.org/10.5194/bg-19-2855-2022, 2022
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Tropical peat-draining rivers contain high amounts of carbon. Surprisingly, measured carbon dioxide (CO2) emissions from those rivers are comparatively moderate. We compiled data from 10 Southeast Asian rivers and found that CO2 production within these rivers is hampered by low water pH, providing a natural threshold for CO2 emissions. Furthermore, we find that enhanced carbonate input, e.g. caused by human activities, suspends this natural threshold and causes increased CO2 emissions.
Amy E. Pickard, Marcella Branagan, Mike F. Billett, Roxane Andersen, and Kerry J. Dinsmore
Biogeosciences, 19, 1321–1334, https://doi.org/10.5194/bg-19-1321-2022, https://doi.org/10.5194/bg-19-1321-2022, 2022
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Peatlands have been subject to a range of land management regimes over the past century. This has affected the amount of carbon that drains into surrounding streams and rivers. In our study, we measured carbon concentrations in streams draining from drained, non-drained, and restored areas of the Flow Country blanket bog in N Scotland. We found that drained peatland had higher concentrations and fluxes of carbon relative to non-drained areas. Restored peatland areas were highly variable.
Brynn O'Donnell and Erin R. Hotchkiss
Biogeosciences, 19, 1111–1134, https://doi.org/10.5194/bg-19-1111-2022, https://doi.org/10.5194/bg-19-1111-2022, 2022
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A stream is defined by flowing water, but higher flow from storms is also a frequent disturbance. This paper tests how higher flow changes stream metabolism (respiration and photosynthesis, R and P). P was less resistant to changes in flow compared to R, and P took longer to recover from storms than R (2.2 versus 0.6 d). Further work on metabolic responses to flow disturbance is critical given projected increases in storms and the influence of higher flows on ecosystem health and functioning.
Thibault Lambert, Pascal Perolo, Nicolas Escoffier, and Marie-Elodie Perga
Biogeosciences, 19, 187–200, https://doi.org/10.5194/bg-19-187-2022, https://doi.org/10.5194/bg-19-187-2022, 2022
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The bacterial mineralization of dissolved organic matter (DOM) in inland waters contributes to CO2 emissions to the atmosphere. Human activities affect DOM sources. However, the implications on DOM mineralization are poorly known. Combining sampling and incubations, we showed that higher bacterial respiration in agro-urban streams related to a labile pool from aquatic origin. Therefore, human activities may have a limited impact on the net carbon exchanges between inland waters and atmosphere.
Boyi Liu, Mingyang Tian, Kaimin Shih, Chun Ngai Chan, Xiankun Yang, and Lishan Ran
Biogeosciences, 18, 5231–5245, https://doi.org/10.5194/bg-18-5231-2021, https://doi.org/10.5194/bg-18-5231-2021, 2021
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Spatial and temporal patterns of pCO2 in the subtropical Dong River basin were mainly affected by C inputs and in-stream metabolism, both of which varied due to differential catchment settings, land cover, and hydrological conditions. CO2 fluxes in the wet season were 2-fold larger than in the dry season due to high pCO2 and turbulence caused by high flow velocity. The absence of high CO2 fluxes in small rivers could be associated with the depletion effect caused by abundant precipitation.
Sergey N. Vorobyev, Jan Karlsson, Yuri Y. Kolesnichenko, Mikhail A. Korets, and Oleg S. Pokrovsky
Biogeosciences, 18, 4919–4936, https://doi.org/10.5194/bg-18-4919-2021, https://doi.org/10.5194/bg-18-4919-2021, 2021
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In order to quantify riverine carbon (C) exchange with the atmosphere in permafrost regions, we report a first assessment of CO2 and CH4 concentration and fluxes of the largest permafrost-affected river, the Lena River, during the peak of spring flow. The results allowed identification of environmental factors controlling GHG concentrations and emission in the Lena River watershed; this new knowledge can be used for foreseeing future changes in C balance in permafrost-affected Arctic rivers.
Jan Greiwe, Markus Weiler, and Jens Lange
Biogeosciences, 18, 4705–4715, https://doi.org/10.5194/bg-18-4705-2021, https://doi.org/10.5194/bg-18-4705-2021, 2021
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We analyzed variability in diel nitrate patterns at three locations in a lowland stream. Comparison of time lags between monitoring sites with water travel time indicated that diel patterns were created by in-stream processes rather than transported downstream from an upstream point of origin. Most of the patterns (70 %) could be explained by assimilatory nitrate uptake. The remaining patterns suggest seasonally varying dominance and synchronicity of different biochemical processes.
Matthias Pucher, Peter Flödl, Daniel Graeber, Klaus Felsenstein, Thomas Hein, and Gabriele Weigelhofer
Biogeosciences, 18, 3103–3122, https://doi.org/10.5194/bg-18-3103-2021, https://doi.org/10.5194/bg-18-3103-2021, 2021
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Dissolved organic matter is an important carbon source in aquatic ecosystems, yet the uptake processes are not totally understood. We found evidence for the release of degradation products, efficiency loss in the uptake with higher concentrations, stimulating effects, and quality-dependent influences from the benthic zone. To conduct this analysis, we included interactions in the equations of the nutrient spiralling concept and solve it with a Bayesian non-linear fitting algorithm.
Xin Wang, Ting Liu, Liang Wang, Zongguang Liu, Erxiong Zhu, Simin Wang, Yue Cai, Shanshan Zhu, and Xiaojuan Feng
Biogeosciences, 18, 3015–3028, https://doi.org/10.5194/bg-18-3015-2021, https://doi.org/10.5194/bg-18-3015-2021, 2021
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We show a comprehensive monitoring dataset on the discharge and carbon transport in a small alpine river on the Qinghai–Tibetan Plateau, where riverine carbon increased downstream in the pre-monsoon season due to an increasing contribution of organic matter derived from seasonal permafrost thaw while it fluctuated in the monsoon season induced by sporadic precipitation. These results indicate a high sensitivity of riverine carbon in alpine headwater catchments to local hydrological events.
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.
Lyla L. Taylor, Charles T. Driscoll, Peter M. Groffman, Greg H. Rau, Joel D. Blum, and David J. Beerling
Biogeosciences, 18, 169–188, https://doi.org/10.5194/bg-18-169-2021, https://doi.org/10.5194/bg-18-169-2021, 2021
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Enhanced rock weathering (ERW) is a carbon dioxide removal (CDR) strategy involving soil amendments with silicate rock dust. Over 15 years, a small silicate application led to net CDR of 8.5–11.5 t CO2/ha in an acid-rain-impacted New Hampshire forest. We accounted for the total carbon cost of treatment and compared effects with an adjacent, untreated forest. Our results suggest ERW can improve the greenhouse gas balance of similar forests in addition to mitigating acid rain effects.
Scott Zolkos, Suzanne E. Tank, Robert G. Striegl, Steven V. Kokelj, Justin Kokoszka, Cristian Estop-Aragonés, and David Olefeldt
Biogeosciences, 17, 5163–5182, https://doi.org/10.5194/bg-17-5163-2020, https://doi.org/10.5194/bg-17-5163-2020, 2020
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High-latitude warming thaws permafrost, exposing minerals to weathering and fluvial transport. We studied the effects of abrupt thaw and associated weathering on carbon cycling in western Canada. Permafrost collapse affected < 1 % of the landscape yet enabled carbonate weathering associated with CO2 degassing in headwaters and increased bicarbonate export across watershed scales. Weathering may become a driver of carbon cycling in ice- and mineral-rich permafrost terrain across the Arctic.
Yingjie Cao, Yingxue Xuan, Changyuan Tang, Shuai Guan, and Yisheng Peng
Biogeosciences, 17, 3875–3890, https://doi.org/10.5194/bg-17-3875-2020, https://doi.org/10.5194/bg-17-3875-2020, 2020
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About half of the global CO2 sequestration due to chemical weathering occurs in warm and high-runoff regions. To evaluate the temporary and net sinks of atmospheric CO2 due to chemical weathering, we selected a typical subtropical catchment as our study area and did fieldwork to sample surface water along the main channel and major tributaries in 1 hydrological year. The result of mass balance calculation showed that human activities dramatically decreased the CO2 net sink.
Laure Gandois, Alison M. Hoyt, Stéphane Mounier, Gaël Le Roux, Charles F. Harvey, Adrien Claustres, Mohammed Nuriman, and Gusti Anshari
Biogeosciences, 17, 1897–1909, https://doi.org/10.5194/bg-17-1897-2020, https://doi.org/10.5194/bg-17-1897-2020, 2020
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Worldwide, peatlands are important sources of dissolved organic matter (DOM) and trace metals (TMs) to surface waters, and these fluxes may increase with peatland degradation. In Southeast Asia, tropical peatlands are being rapidly deforested and drained. This work aims to address the fate of organic carbon and its role as a trace metal carrier in drained peatlands of Indonesia.
Xiaohui Zhang, Moritz Müller, Shan Jiang, Ying Wu, Xunchi Zhu, Aazani Mujahid, Zhuoyi Zhu, Mohd Fakharuddin Muhamad, Edwin Sien Aun Sia, Faddrine Holt Ajon Jang, and Jing Zhang
Biogeosciences, 17, 1805–1819, https://doi.org/10.5194/bg-17-1805-2020, https://doi.org/10.5194/bg-17-1805-2020, 2020
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This study offered detailed information on dFe concentrations, distribution and the magnitude of yield in the Rajang River, the largest river in Malaysia. Three blackwater rivers, draining from peatlands, were also included in our study. Compared with the Rajang River, the dFe concentrations and yield from three blackwater rivers were much higher. The precipitation and agricultural activities, such as palm oil plantations, may markedly increase the concentration dFe in these tropical rivers.
Caroline Coch, Bennet Juhls, Scott F. Lamoureux, Melissa J. Lafrenière, Michael Fritz, Birgit Heim, and Hugues Lantuit
Biogeosciences, 16, 4535–4553, https://doi.org/10.5194/bg-16-4535-2019, https://doi.org/10.5194/bg-16-4535-2019, 2019
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Climate change affects Arctic ecosystems. This includes thawing of permafrost (ground below 0 °C) and an increase in rainfall. Both have substantial impacts on the chemical composition of river water. We compared the composition of small rivers in the low and high Arctic with the large Arctic rivers. In comparison, dissolved organic matter in the small rivers is more susceptible to degradation; thus, it could potentially increase carbon dioxide emissions. Rainfall events have a similar effect.
Benedikt J. Werner, Andreas Musolff, Oliver J. Lechtenfeld, Gerrit H. de Rooij, Marieke R. Oosterwoud, and Jan H. Fleckenstein
Biogeosciences, 16, 4497–4516, https://doi.org/10.5194/bg-16-4497-2019, https://doi.org/10.5194/bg-16-4497-2019, 2019
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Increased dissolved organic carbon (DOC) concentration in streams can pose a threat to downstream water resources. Analyzing data from an in-stream probe we found that hydroclimatic and hydrological drivers can describe up to 72 % of the observed DOC concentration and composition variability. Variability was found to be highest during discharge events with warm and dry preconditions. The findings suggest an impact of climate change on DOC exports and thus also on downstream water quality.
Shan Jiang, Moritz Müller, Jie Jin, Ying Wu, Kun Zhu, Guosen Zhang, Aazani Mujahid, Tim Rixen, Mohd Fakharuddin Muhamad, Edwin Sien Aun Sia, Faddrine Holt Ajon Jang, and Jing Zhang
Biogeosciences, 16, 2821–2836, https://doi.org/10.5194/bg-16-2821-2019, https://doi.org/10.5194/bg-16-2821-2019, 2019
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Three cruises were conducted in the Rajang River estuary, Malaysia. The results revealed that the decomposition of terrestrial organic matter and the subsequent soil leaching were the main sources of dissolved inorganic nitrogen (DIN) in the fresh river water. Porewater exchange and ammonification enhanced DIN concentrations in the estuary water, while intensities of DIN addition varied between seasons. The riverine DIN flux could reach 101.5 ton(N) / d, supporting the coastal primary producers.
Edwin Sien Aun Sia, Jing Zhang, Shan Jiang, Zhuoyi Zhu, Gonzalo Carrasco, Faddrine Holt Jang, Aazani Mujahid, and Moritz Müller
Biogeosciences Discuss., https://doi.org/10.5194/bg-2019-219, https://doi.org/10.5194/bg-2019-219, 2019
Revised manuscript not accepted
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Nutrient loads carried by large rivers and discharged into the continental shelf and coastal waters are vital to support primary production. Our knowledge of tropical river systems is fragmented with very few seasonal studies available for Southeast Asia (SEA). We present data from three sampling campaigns on the longest river in Malaysia, the Rajang river. Our results show the generalization of SEA as a nutrient hotspot might not hold true for all regions and requires further investigation.
Brian C. Doyle, Elvira de Eyto, Mary Dillane, Russell Poole, Valerie McCarthy, Elizabeth Ryder, and Eleanor Jennings
Biogeosciences, 16, 1053–1071, https://doi.org/10.5194/bg-16-1053-2019, https://doi.org/10.5194/bg-16-1053-2019, 2019
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This study explores the drivers of variation in the water colour of rivers, and hence organic carbon export, in a blanket peatland catchment. We used 6 years of weekly river water colour data (2011 to 2016) from three proximate river sub-catchments in western Ireland. in tandem with a range of topographical, hydrological and climate data, to discover the principle environmental drivers controlling changes in colour concentration in the rivers.
Manab Kumar Dutta, Sanjeev Kumar, Rupa Mukherjee, Prasun Sanyal, and Sandip Kumar Mukhopadhyay
Biogeosciences, 16, 289–307, https://doi.org/10.5194/bg-16-289-2019, https://doi.org/10.5194/bg-16-289-2019, 2019
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The study focused on understanding C biogeochemistry of two adjacently located estuaries undergoing different levels of anthropogenic stresses. Different parameters related to C cycling were measured in an anthropogenically influenced and a mangrove-dominated estuary. Although the entire estuarine system acted as a source of carbon dioxide to the regional atmosphere, emission approximately 17 times higher was noticed from the anthropogenically affected estuary compared to mangrove-dominated one.
Ivan V. Krickov, Artem G. Lim, Rinat M. Manasypov, Sergey V. Loiko, Liudmila S. Shirokova, Sergey N. Kirpotin, Jan Karlsson, and Oleg S. Pokrovsky
Biogeosciences, 15, 6867–6884, https://doi.org/10.5194/bg-15-6867-2018, https://doi.org/10.5194/bg-15-6867-2018, 2018
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We tested the effect of climate, permafrost and physio-geographical landscape parameters on particulate C, N and P concentrations in small- and medium- sized rivers in the Western Siberian Lowland (WSL). We discovered a maximum of particulate C and N concentrations at the beginning of the permafrost appearance. A northward shift of permafrost boundaries may increase the particulate C and N export by WSL rivers to the Arctic Ocean by a factor of 2.
Wenjing Liu, Zhifang Xu, Huiguo Sun, Tong Zhao, Chao Shi, and Taoze Liu
Biogeosciences, 15, 4955–4971, https://doi.org/10.5194/bg-15-4955-2018, https://doi.org/10.5194/bg-15-4955-2018, 2018
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The southeastern coastal region is the top acid-rain-impacted area in China. It is worth evaluating the acid deposition impacts on chemical weathering and CO2 consumption there. River water geochemistry evidenced an overestimation of CO2 sequestration if H2SO4/HNO3 involvement was ignored, which accounted for 33.6 % of the total flux by silicate weathering in this area. This study quantitatively highlights the anthropogenic acid effects on chemical weathering and associated CO2 consumption.
Thi Phuong Quynh Le, Cyril Marchand, Cuong Tu Ho, Nhu Da Le, Thi Thuy Duong, XiXi Lu, Phuong Kieu Doan, Trung Kien Nguyen, Thi Mai Huong Nguyen, and Duy An Vu
Biogeosciences, 15, 4799–4814, https://doi.org/10.5194/bg-15-4799-2018, https://doi.org/10.5194/bg-15-4799-2018, 2018
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The Red River is a typical south-east Asian river, strongly affected by climate and human activity. This study showed the spatial and seasonal variability of CO2 emissions at the water–air interface of the lower part of this river due to natural conditions (meteo-hydrological-geomorphological characteristics) and human activities (dam impoundment, population, land use). The Red River water was supersaturated with CO2, providing a mean water–air CO2 flux of 530 ± 17 mmol m−2 d−1.
Wei Wen Wong, Jesse Pottage, Fiona Y. Warry, Paul Reich, Keryn L. Roberts, Michael R. Grace, and Perran L. M. Cook
Biogeosciences, 15, 3953–3965, https://doi.org/10.5194/bg-15-3953-2018, https://doi.org/10.5194/bg-15-3953-2018, 2018
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Over-enrichment of nitrate can pose substantial risk to the quality of freshwater ecosystems. Hence, understanding the dynamics of nitrate is the key to better management of waterways. This study evaluates the relationship between the effects of land use and rainfall on the major sources and processing of nitrate within and between five streams in five catchments spanning an agricultural land use gradient. We found that rainfall exerted significant control over the fate of nitrate.
Lishan Ran, Mingyang Tian, Nufang Fang, Suiji Wang, Xixi Lu, Xiankun Yang, and Frankie Cho
Biogeosciences, 15, 3857–3871, https://doi.org/10.5194/bg-15-3857-2018, https://doi.org/10.5194/bg-15-3857-2018, 2018
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We systematically assessed the transport and fate of riverine carbon in the moderate-sized Wuding catchment on the Chinese Loess Plateau by constructing a riverine carbon budget and further relating it to terrestrial ecosystem productivity. The riverine carbon export accounted for 16 % of the catchment's net ecosystem production (NEP). It seems that a significant fraction of terrestrial NEP in this catchment is laterally transported from the terrestrial biosphere to the drainage network.
Robert O. Hall Jr. and Hilary L. Madinger
Biogeosciences, 15, 3085–3092, https://doi.org/10.5194/bg-15-3085-2018, https://doi.org/10.5194/bg-15-3085-2018, 2018
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Streams exchange oxygen with the atmosphere, but this rate is difficult to measure. We added argon to small mountain streams to estimate gas exchange. We compared these rates with sulfur hexafluoride, an intense greenhouse gas. Argon worked well to measure gas exchange, but had higher-than-predicted rates than sulfur hexafluoride. Argon exchange is more likely to represent that for oxygen because they share similar physical properties. We suggest argon to measure gas exchange in small streams.
Ji-Hyung Park, Omme K. Nayna, Most S. Begum, Eliyan Chea, Jens Hartmann, Richard G. Keil, Sanjeev Kumar, Xixi Lu, Lishan Ran, Jeffrey E. Richey, Vedula V. S. S. Sarma, Shafi M. Tareq, Do Thi Xuan, and Ruihong Yu
Biogeosciences, 15, 3049–3069, https://doi.org/10.5194/bg-15-3049-2018, https://doi.org/10.5194/bg-15-3049-2018, 2018
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Human activities are drastically altering water and material flows in river systems across Asia. This review provides a conceptual framework for assessing the human impacts on Asian river C fluxes and an update on anthropogenic alterations of riverine C fluxes, focusing on the impacts of water pollution and river impoundments on CO2 outgassing from the rivers draining South, Southeast, and East Asian regions that account for the largest fraction of river discharge and C exports from Asia.
Chung-Te Chang, Jr-Chuan Huang, Lixin Wang, Yu-Ting Shih, and Teng-Chiu Lin
Biogeosciences, 15, 2379–2391, https://doi.org/10.5194/bg-15-2379-2018, https://doi.org/10.5194/bg-15-2379-2018, 2018
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Our analysis of ion input–output budget illustrates that hydrochemical responses to typhoon storms are distinctly different from those of regular storms. In addition, even mild land use change may have large impacts on nutrient exports/losses. We propose that hydrological models should separate hydrochemical processes into regular and extreme conditions to better capture the whole spectrum of hydrochemical responses to a variety of climate conditions.
Camille Minaudo, Florence Curie, Yann Jullian, Nathalie Gassama, and Florentina Moatar
Biogeosciences, 15, 2251–2269, https://doi.org/10.5194/bg-15-2251-2018, https://doi.org/10.5194/bg-15-2251-2018, 2018
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We developed the model QUALity-NETwork (QUAL-NET) to simulate water quality variations in large drainage networks. This model is accurate enough to represent processes occurring over short periods of time such as storm events and helps to fully understand water quality variations in stream networks in the context of climate change and varying human pressures. It was tested on the Loire River and provided good performances and a new understanding of the functioning of the river.
Michael P. Schwab, Julian Klaus, Laurent Pfister, and Markus Weiler
Biogeosciences, 15, 2177–2188, https://doi.org/10.5194/bg-15-2177-2018, https://doi.org/10.5194/bg-15-2177-2018, 2018
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We studied the diel fluctuations of dissolved organic carbon (DOC) concentrations in a small stream in Luxembourg. We identified an increased proportion of DOC from terrestrial sources as responsible for the peaks in DOC in the afternoon. Warmer water temperatures in the riparian zone in the afternoon increased the amount of water flowing towards the stream. Consequently, an increased amount of DOC-rich water from the riparian zone was entering the stream.
Cited articles
Amundson, R., Austin, A. T., Schuur, E. A. G., Yoo, K., Matzek, V., Kendall, C., Uebersax, A., Brenner, D., and Baisden, W. T.: Global patterns of the isotopic composition of soil and plant nitrogen, Global Biogeochem. Cy., 17, 1031, https://doi.org/10.1029/2002GB001903, 2003.
Balesdent, J., Girardin, C., and Mariotti, A.: Site-related δ13C of tree leaves and soil organic matter in a temperate forest, Ecology, 74, 1713–1721, 1993.
Bellanger, B., Huon, S., Velasquez, F., Vallès, V., Girardin, C., and Mariotti, A.: Monitoring soil organic carbon erosion with δ13C and δ15N on experimental field plots in the Venezuelan Andes, Catena, 58, 125–150, 2004.
Ben Slimane, A., Raclot, D., Evrard, O., Sanaa, M., Lefèvre, I., Ahmadi, M., Tounsi, M., Rumpel, C., Ben Mammou, A., and Le Bissonnais, Y.: Fingerprinting sediment sources in the outlet reservoir of a hilly cultivated catchment in Tunisia, J. Soils Sediments, 13, 801–815, 2013.
Bricquet, J.-P., Boonsaner, A., Bouahom, B., and Toan, T. D.: Statistical Analysis of Long Series Rainfall Data: A Regional Study in South-East Asia, in: from soil research to land and water management: harmonizing people and nature: proceedings of the IWMI-ADB project annual meeting and 7th MSEC assembly, edited by: Maglinao, A. R., Valentin, C., and Penning de Vries, F., Vientiane (LAO), Vientiane (LAO): IWMI-ADB Project Annual Meeting; MSEC Assembly, 7, 83–89, 2003.
Buttle, J. M.: Isotope hydrograph separations and rapid delivery of pre-event water from drainage basins, Prog. Phys. Geogr., 18, 16–41, 1994.
Chaplot, V. and Poesen, J.: Sediment, soil organic carbon and runoff delivery at various spatial scales, Catena, 88, 46–56, 2012.
Chaplot, V., Coadoulebrozec, E., Silvera, N., and Valentin, C.: Spatial and temporal assessment of linear erosion in catchments under sloping lands of northern Laos, Catena, 63, 167–184, 2005.
Chaplot, V., Podwojewski, P., Phachomphon, K., and Valentin, C.: Soil erosion impact on soil organic carbon spatial variability on steep tropical slopes, Soil Sci. Soc. Am. J., 73, 769–779, 2009.
Chow, V. T., Maidment, D. R., and Mays, L. W.: Applied Hydrology, McGraw Hill Book Co., 572 pp., 1988.
Clark, K. E., Hilton, R. G., West, A. J., Malhi, Y., Gröcke, D. R., Bryant, C. L., Ascough, P. L., Robles Caceres, A., and New, M.: New views on "old" carbon in the Amazon River: Insight from the source of organic carbon eroded from the Peruvian Andes, Geochemistry, Geophysics, Geosystems, 14, 1644–1659, 2013.
Copard, Y., Amiotte-Suchet, P., and Di-Giovanni, C.: Storage and release of fossil organic carbon related to weathering of sedimentary rocks, Earth Planet. Sci. Lett., 258, 345–357, 2007.
Coplen, T. B., Kendall, C., and Hopple, J.: Comparison of stable isotope reference samples, Nature, 302, 236–238, 1983.
Dansgaard, W.: Stable isotopes in precipitation, Tellus, 16, 436–468, 1964.
Degens, E. T., Kempe, S., and Richey, J. E.: Summary: Biogeochemistry of major world rivers, in: Biogeochemistry of major world rivers, edited by: Degens, E. T., Kempe, S., and Richey, J. E., SCOPE Rep. 42, John Wiley and Sons, Chichester, 323–347, 1991.
de Rouw, A., Soulileuth, B., and Huon, S.: Stable carbon isotope ratios in soil and vegetation shift with cultivation, Agriculture, Ecosyst. Environ., 200, 161–168, 2015.
Descroix, L., González Barrios, J. L., Viramontes, D., Poulenard, J., Anaya, E., Esteves, M., and Estrada, J.: Gully and sheet erosion on subtropical mountain slopes: Their respective roles and the scale effect, Catena, 72, 325–339, 2008.
Dixon, R. K., Brown, S., Houghton, R. A., Solomon, A. M., Trexler, M. C., and Wisniewski, J.: Carbon pools and flux of global forest ecosystems, Science, 263, 185–191, 1994.
Downing, J. A., Cole, J. J., Middelburg, J. J., Striegl, R. G., Duarte, C. M., Kortelainen, P., Prairie, Y. T., and Laube, K. A.: Sediment organic carbon burial in agriculturally eutrophic impoundments over the last century, Global Biogeochem. Cy., 22, 1–10, 2008.
Dupin, B., de Rouw, A., Phantahvong, K. B., and Valentin, C.: Assessment of tillage erosion rates on steep slopes in northern Laos, Soil Till. Res., 103, 119–126, 2009.
Duvert, C., Gratiot, N., Evrard, O., Navratil, O., Némery, J., Prat, C., and Esteves, M.: Drivers of erosion and suspended sediment transport in three headwater catchments of the Mexican Central Highlands, Geomorphology, 123, 243–256, 2010.
Ellis, E. E., Keil, R. G., Ingalls, A. E., Richey, J. E., and Alin, S. R.: Seasonal variability in the sources of particulate organic matter of the Mekong River as discerned by elemental and lignin analyses, J. Geophys. Res., 117, G01038, https://doi.org/10.1029/2011JG001816, 2012.
Epstein, S. and Mayeda, T.: Variation of 18O content of waters from natural sources, Geochim. Cosmochim. Ac., 4, 213–224, 1953.
Evrard, O., Némery, J., Gratiot, N., Duvert, C., Ayrault, S., Lefèvre, I., Poulenard, J., Prat, C., Bonté, P., and Esteves, M.: Sediment dynamics during the rainy season in tropical highland catchments of central Mexico using fallout radionuclides, Geomorphology, 124, 42–54, 2010.
Gateuille, D., Evrard, O., Lefèvre, I., Moreau-Guigon, E., Alliot, F., Chevreuil, M., and Mouchel, J.-M.: Mass balance and depollution times of Polycyclic Aromatic Hydrocarbons in rural nested catchments of an early industrialized region (Orgeval River, Seine River basin, France), Sci. Total Environ., 470/471, 608–617, 2014.
Girardin, C. and Mariotti, A.: Analyse isotopique du 13C en abondance naturelle un système automatique avec robot préparateur, Cah. Orstom, sér. Pédol., 120, 371–380, 1991.
Goldsmith, S. T., Carey, A. E., Lyons, W. B., Kao, S.-J., Lee, T.-Y., and Chen, J.: Extreme storm events, landscape denudation, and carbon sequestration: Typhoon Mindulle, Choshui River, Taiwan, Geology, 36, 483–486, 2008.
Gonfiantini, R.: Standards for stable isotope measurements in natural compounds, Nature, 271, 534–536, 1978.
Gourdin, E., Evrard, O., Huon, S., Lefèvre, I., Ribolzi, O., Reyss, J.-L., Sengtaheuanghoung, O., and Ayrault, S.: Suspended sediment dynamics in a Southeast Asian mountainous catchment: combining river monitoring and fallout radionuclide tracers, J. Hydrol., 519, 1811–1823, 2014.
Graz, Y., Di-Giovanni, C., Copard, Y., Mathys, N., Cras, A., and Marc, V.: Annual fossil organic carbon delivery due to mechanical and chemical weathering of marly badlands areas, Earth Surf. Process. Landforms, 37, 1263–1271, 2012.
Gurnell, A. M.: Analogies between mineral sediment and vegetative particle dynamics in fluvial systems, Geomorphology, 89, 9–22, 2007.
Harris, D. M., McDonnell, J. J., and Rodhe, A.: Hydrograph separation using continuous open system isotope mixing, Water Resour. Res., 31, 157–171, 1995.
Hilton, R. G., Galy, A., Hovius, N., Horng, M.-J., and Chen, H.: The isotopic composition of particulate organic carbon in mountain rivers of Taiwan, Geochim. Cosmochim. Ac., 74, 3164–3181, 2010.
Hilton, R. G., Galy, A., Hovius, N., Horng, M.-J., and Chen, H.: Efficient transport of fossil organic carbon to the ocean by steep mountain rivers: An orogenic carbon sequestration mechanism, Geology, 39, 71–74, 2011.
Houghton, R. A.: Tropical deforestation and atmospheric carbon dioxide, Clim. Change, 19, 99–118, 1991.
Hsieh, J. C. C., Chadwick, O. A., Kelly, E. F., and Savin, S. M.: Oxygen isotopic composition of soil water: Quantifying evaporation and transpiration, Geoderma, 82, 269–293, 1998.
Huang, T.-H., Fu, Y.-H., Pan, P.-Y., and Chen, C.-T. A.: Fluvial carbon fluxes in tropical rivers, Curr. Opin. Environ. Sustain., 4, 162–169, 2012.
Huon, S., Bellanger, B., Bonté, P., Sogon, S., Podwojewski, P., Girardin, C., Valentin, C., De Rouw, A., Velasquez, F., Bricquet, J.-P., and Mariotti, A.: Monitoring soil organic carbon erosion with isotopic tracers: two case studies on cultivated tropical catchments with steep slopes (Laos, Venezuela), in: Advances in Soil Science, Soil erosion and carbon dynamics , edited by: Roose, E., Lal, R., Barthès, B., Feller C., and Stewart, B. A., CRC Press, Boca Raton. Florida (USA), 301–328, 2006.
Huon, S., de Rouw, A., Bonté, P., Robain, H., Valentin, C., Lefèvre, I., Girardin, C., Le Troquer, Y., Podwojewski, P., and Sengtaheuanghoung O.: Long-term soil carbon loss and accumulation in a catchment following the conversion of forest to arable land in northern Laos, Agriculture, Ecosyst. Environ., 169, 43–57, 2013.
Kao, S. J. and Liu, K. K.: Fluxes of dissolved and nonfossil particulate organic carbon from an Oceania small river (Lanyang Hsi) in Taiwan, Biogeochemistry, 39, 255–269, 1997.
Kao, S. J. and Liu, K. K.: Stable carbon and nitrogen isotope systematics in a human- disturbed watershed (Lanyang-Hsi) in Taiwan and the estimation of biogenic particulate organic carbon and nitrogen fluxes, Global Biogeochem. Cy., 14, 189–198, 2000.
Klaus, J. and McDonnell, J. J.: Hydrograph separation using stable isotopes: Review and evaluation, J. Hydrol., 505, 47–64, 2013.
Koiter, A. J., Owens, P. N., Petticrew, E. L., and Lobb, D. A.: The behavioural characteristics of sediment properties and their implications for sediment fingerprinting as an approach for identifying sediment sources in river basins, Earth-Sci. Rev., 125, 24–42, 2013.
Ladouche, B., Probst, A., Viville, D., Idir, S., Baqué, D., Loubet, M., Probst, J.-L., and Bariac, T.: Hydrograph separation using isotopic , chemical and hydrological approaches (Strengbach catchment, France), J. Hydrol., 242, 255–274, 2001.
Lal, R.: Soil erosion and the global carbon budget, Environ. Int., 29, 437–450, 2003.
Lenzi, M. A. and Marchi, L.: Suspended sediment load during floods in a small stream of the Dolomites (Northeastern Italy), Catena, 39, 267–282, 2000.
Ludwig, W., Probst, J., and Kempe, S.: Predicting the oceanic input of organic carbon by continental erosion, Global Biogeochem. Cy., 10, 23–41, 1996.
Mariotti, A., Lancelot, C., and Billen, G.: Natural isotopic composition of nitrogen as a tracer of origin for suspended organic matter in the Scheldt estuary, Geochim. Cosmochim. Ac., 48, 549–555, 1983.
Masiello, C. A. and Druffel, E. R. M.: Carbon isotope geochemistry of the Santa Clara River, Global Biogeochem. Cy., 15, 407–416, 2001.
McDonnell, J. J., Bonell, M., Stewart, M. K., and Pearce, A. J.: Deuterium variations in storm rainfall: implications for stream hydrograph separation, Water Resour. Res., 26, 455–458, 1990.
Meybeck, M.: Riverine transport of atmospheric carbon: sources, global typology and budget, Water. Air. Soil Pollut., 70, 443–463, 1993.
Meybeck, M.: Origins and behaviors of carbon species in world rivers, in: Soil erosion and Carbon Dynamics, edited by: Roose, E., Lal, R.; Barthès, B., Feller C., and Stewart, B. A., CRC Press, Boca Raton, Florida (USA), 209–238, 2006.
Milliman, J. D. and Syvitski, J. P. M.: Geomorphic / tectonic control of sediment discharge to the ocean?: the importance of small mountainous rivers, J. Geol., 100, 525–544, 1992.
Patin, J., Mouche, E., Ribolzi, O., Chaplot, V., Sengtahevanghoung, O., Latsachak, K. O., Soulileuth, B., and Valentin, C.: Analysis of runoff production at the plot scale during a long-term survey of a small agricultural catchment in Lao PDR, J. Hydrol., 426/427, 79–92, 2012.
Quinton, J. N., Govers, G., Van Oost, K., and Bardgett, R. D.: The impact of agricultural soil erosion on biogeochemical cycling, Nat. Geosci., 3, 311–314, 2010.
Raymond, P. A. and Bauer, J. E.: Riverine export of aged terrestrial organic matter to the North Atlantic Ocean, Nature, 409, 497–500, 2001.
Ribolzi, O., Andrieux, P., Valles, V., Bouzigues, R., Bariac, T., and Voltz, M.: Contribution of groundwater and overland flows to storm flow generation in a cultivated Mediterranean catchment, Quantification by natural chemical tracing, J. Hydrol., 233, 241–257, 2000.
Ribolzi, O., Cuny, J., Sengsoulichanh, P., Pierret, A., Thiébaux, J. P., Huon, S., Bourdon, E., Robain, E., and Sengtaheuanghoung O.: Assessment of water quality along a tributary of the Mekong River in a mountainous, mixed land-use environment of the Lao P.D.R., Lao J. Agricult. Forest., 17, 91–111, 2008.
Ribolzi, O., Cuny, J., Sengsoulichanh, P., Mousquès, C., Soulileuth, B., Pierret, A., Huon, S., and Sengtaheuanghoung O.: Land use and water quality along a Mekong tributary in northern Lao P.D.R., Environ. Manage., 47, 291–302, 2010.
Ribolzi, O., Patin, J., Bresson, L. M., Latsachack, K. O., Mouche, E., Sengtaheuanghoung, O., Silvera, N., Thiébaux, J. P., and Valentin, C.: Impact of slope gradient on soil surface features and infiltration on steep slopes in northern Laos, Geomorphology, 127, 53–63, 2011.
Ritchie, J. C. and McHenry, J. R.: Application of Radioactive Fallout Cesium-137 for Measuring Soil Erosion and Sediment Accumulation Rates and Patterns?: A Review, J. Environ. Qual., 19, 215–233, 1990.
Ritchie, J. C. and McCarty, G. W.: 137Cesium and soil carbon in a small agricultural watershed, Soil Till. Res., 69, 45–51, 2003.
Rumpel, C., Chaplot, V., Planchon, O., Bernadou, J., Valentin, C., and Mariotti, A.: Preferential erosion of black carbon on steep slopes with slash and burn agriculture, Catena, 65, 30–40, 2006.
Sarmiento, J. L. and Gruber, N.: Sinks for anthropogenic carbon, Physics Today, 55, 30–36, 2002.
Schindler Wildhaber, Y., Liechti, R., and Alewell, C.: Organic matter dynamics and stable isotope signature as tracers of the sources of suspended sediment, Biogeosciences, 9, 1985–1996, https://doi.org/10.5194/bg-9-1985-2012, 2012.
Sklash, M. G. and Farvolden, R. N.: The role of groundwater in storm runoff, J. Hydrol., 43, 45–65, 1979.
Smith, H. G. and Blake, W. H.: Sediment fingerprinting in agricultural catchments: A critical re-examination of source discrimination and data corrections, Geomorphology, 204, 177–191, 2014.
Smith, J. C., Galy, A., Hovius, N., Tye, A. M., Turowski, J. M., and Schleppi, P.: Runoff-driven export of particulate organic carbon from soil in temperate forested uplands, Earth Planet. Sci. Lett., 365, 198–208, 2013.
Soto, B., Basanta, R., Perez, R., and Diaz-Fierros, F.: An experimental study of the influence of traditional slash-and-burn practices on soil erosion, Catena, 24, 13–23, 1995.
Syvitski, J. P. M., Vörösmarty, C. J., Kettner, A. J., and Green, P.: Impact of humans on the flux of terrestrial sediment to the global coastal ocean, Science, 308, 376–80, 2005.
Tanik, A., Beler Baykal, B., and Gonenc, I. E.: The impact of agricultural pollutants in six drinking water reservoirs, Water Sci. Technol., 40, 11–17, 1999.
Thothong, W., Huon, S., Janeau, J.-L., Boonsaner, A., de Rouw, A., Planchon, O., Bardoux, G., and Parkpian, P.: Impact of land use change and rainfall on sediment and carbon accumulation in a water reservoir of North Thailand, Agriculture, Ecosyst. Environ., 140, 521–533, 2011.
UNESCO (United Nations Educational Scientific and Cultural Organization): FAO/UNESCO Soil map of the world, 1:5 000 000 Vol.1. Paris: UNESCO, 1974.
Valentin, C., Agus, F., Alamban, R., Boosaner, A., Bricquet, J. P., Chaplot, V., de Guzman, T., de Rouw, A., Janeau, J. L., Orange, D., Phachomphonh, K., Podwojewski, P., Ribolzi, O., Silvera, N., Subagyono, K., Thiébaux, J. P., and Vadari, T.: Runoff and sediment losses from 27 upland catchments in Southeast Asia: Impact of rapid land use changes and conservation practices, Agriculture, Ecosyst. Environ., 128, 225–238, 2008.
Williams, G. P.: Sediment concentration versus water discharge during single hydrologic events in rivers, J. Hydrol., 111, 89–106, 1989.
Zech, W., Senesi, N., Guggenberger, G., Kaiser, K., Lehmann, J., Miano, T.M., Miltner, A., and Schroth, G.: Factors controlling humification and mineralization of soil organic matter in the tropics, Geoderma, 79, 117–161, 1997.
Short summary
The origin and dynamics of particulate organic matter were studied in a 11.6km² catchment (northern Laos) during the first erosive flood of the 2012 rainy season. Upstream suspended sediments mainly originated from cultivated soils labelled by their C3 vegetation cover. In contrast, channel banks with C4 vegetation supplied significant quantities of sediment to the river downstream. Swamps located along the main stream acted as sediment filters and controlled the composition of suspended POM.
The origin and dynamics of particulate organic matter were studied in a 11.6km² catchment...
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