Articles | Volume 18, issue 4
https://doi.org/10.5194/bg-18-1511-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-18-1511-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
03 Mar 2021
Research article |
| 03 Mar 2021
| 03 Mar 2021
Rapid soil organic carbon decomposition in river systems: effects of the aquatic microbial community and hydrodynamical disturbance
Man Zhao
CORRESPONDING AUTHOR
Department of Earth and Environmental Sciences, KU Leuven, 3001
Leuven, Belgium
Liesbet Jacobs
Department of Earth and Environmental Sciences, KU Leuven, 3001
Leuven, Belgium
Steven Bouillon
Department of Earth and Environmental Sciences, KU Leuven, 3001
Leuven, Belgium
Gerard Govers
Department of Earth and Environmental Sciences, KU Leuven, 3001
Leuven, Belgium
Related authors
No articles found.
Christian Lønborg, Cátia Carreira, Gwenaël Abril, Susana Agustí, Valentina Amaral, Agneta Andersson, Javier Arístegui, Punyasloke Bhadury, Mariana B. Bif, Alberto V. Borges, Steven Bouillon, Maria Ll. Calleja, Luiz C. Cotovicz Jr., Stefano Cozzi, Maryló Doval, Carlos M. Duarte, Bradley Eyre, Cédric G. Fichot, E. Elena García-Martín, Alexandra Garzon-Garcia, Michele Giani, Rafael Gonçalves-Araujo, Renee Gruber, Dennis A. Hansell, Fuminori Hashihama, Ding He, Johnna M. Holding, William R. Hunter, J. Severino P. Ibánhez, Valeria Ibello, Shan Jiang, Guebuem Kim, Katja Klun, Piotr Kowalczuk, Atsushi Kubo, Choon-Weng Lee, Cláudia B. Lopes, Federica Maggioni, Paolo Magni, Celia Marrase, Patrick Martin, S. Leigh McCallister, Roisin McCallum, Patricia M. Medeiros, Xosé Anxelu G. Morán, Frank E. Muller-Karger, Allison Myers-Pigg, Marit Norli, Joanne M. Oakes, Helena Osterholz, Hyekyung Park, Maria Lund Paulsen, Judith A. Rosentreter, Jeff D. Ross, Digna Rueda-Roa, Chiara Santinelli, Yuan Shen, Eva Teira, Tinkara Tinta, Guenther Uher, Masahide Wakita, Nicholas Ward, Kenta Watanabe, Yu Xin, Youhei Yamashita, Liyang Yang, Jacob Yeo, Huamao Yuan, Qiang Zheng, and Xosé Antón Álvarez-Salgado
Earth Syst. Sci. Data, 16, 1107–1119, https://doi.org/10.5194/essd-16-1107-2024, https://doi.org/10.5194/essd-16-1107-2024, 2024
Short summary
Short summary
In this paper, we present the first edition of a global database compiling previously published and unpublished measurements of dissolved organic matter (DOM) collected in coastal waters (CoastDOM v1). Overall, the CoastDOM v1 dataset will be useful to identify global spatial and temporal patterns and to facilitate reuse in studies aimed at better characterizing local biogeochemical processes and identifying a baseline for modelling future changes in coastal waters.
Claude Raoul Müller, Johan Six, Liesa Brosens, Philipp Baumann, Jean Paolo Gomes Minella, Gerard Govers, and Marijn Van de Broek
EGUsphere, https://doi.org/10.5194/egusphere-2023-2170, https://doi.org/10.5194/egusphere-2023-2170, 2023
Short summary
Short summary
Subsoils in the tropics are not yet as extensively studied as in temperate regions. In this study, the conversion of forest to agriculture in a subtropical region affected the concentration of stabilized organic carbon (OC) down to 90 cm depth, while no significant differences between 90 cm and 300 cm were detected. Our results suggest that subsoils below 90 cm are unlikely to accumulate additional stabilized OC through reforestation over decadal periods due to declining OC input with depth.
Vao Fenotiana Razanamahandry, Marjolein Dewaele, Gerard Govers, Liesa Brosens, Benjamin Campforts, Liesbet Jacobs, Tantely Razafimbelo, Tovonarivo Rafolisy, and Steven Bouillon
Biogeosciences, 19, 3825–3841, https://doi.org/10.5194/bg-19-3825-2022, https://doi.org/10.5194/bg-19-3825-2022, 2022
Short summary
Short summary
In order to shed light on possible past vegetation shifts in the Central Highlands of Madagascar, we measured stable isotope ratios of organic carbon in soil profiles along both forested and grassland hillslope transects in the Lake Alaotra region. Our results show that the landscape of this region was more forested in the past: soils in the C4-dominated grasslands contained a substantial fraction of C3-derived carbon, increasing with depth.
Rey Harvey Suello, Simon Lucas Hernandez, Steven Bouillon, Jean-Philippe Belliard, Luis Dominguez-Granda, Marijn Van de Broek, Andrea Mishell Rosado Moncayo, John Ramos Veliz, Karem Pollette Ramirez, Gerard Govers, and Stijn Temmerman
Biogeosciences, 19, 1571–1585, https://doi.org/10.5194/bg-19-1571-2022, https://doi.org/10.5194/bg-19-1571-2022, 2022
Short summary
Short summary
This research shows indications that the age of the mangrove forest and its position along a deltaic gradient (upstream–downstream) play a vital role in the amount and sources of carbon stored in the mangrove sediments. Our findings also imply that carbon capture by the mangrove ecosystem itself contributes partly but relatively little to long-term sediment organic carbon storage. This finding is particularly relevant for budgeting the potential of mangrove ecosystems to mitigate climate change.
Liesa Brosens, Benjamin Campforts, Gerard Govers, Emilien Aldana-Jague, Vao Fenotiana Razanamahandry, Tantely Razafimbelo, Tovonarivo Rafolisy, and Liesbet Jacobs
Earth Surf. Dynam., 10, 209–227, https://doi.org/10.5194/esurf-10-209-2022, https://doi.org/10.5194/esurf-10-209-2022, 2022
Short summary
Short summary
Obtaining accurate information on the volume of geomorphic features typically requires high-resolution topographic data, which are often not available. Here, we show that the globally available 12 m TanDEM-X DEM can be used to accurately estimate gully volumes and establish an area–volume relationship after applying a correction. This allowed us to get a first estimate of the amount of sediment that has been mobilized by large gullies (lavaka) in central Madagascar over the past 70 years.
Arthur Depicker, Gerard Govers, Liesbet Jacobs, Benjamin Campforts, Judith Uwihirwe, and Olivier Dewitte
Earth Surf. Dynam., 9, 445–462, https://doi.org/10.5194/esurf-9-445-2021, https://doi.org/10.5194/esurf-9-445-2021, 2021
Short summary
Short summary
We investigated how shallow landslide occurrence is impacted by deforestation and rifting in the North Tanganyika–Kivu rift region (Africa). We developed a new approach to calculate landslide erosion rates based on an inventory compiled in biased © Google Earth imagery. We find that deforestation increases landslide erosion by a factor of 2–8 and for a period of roughly 15 years. However, the exact impact of deforestation depends on the geomorphic context of the landscape (rejuvenated/relict).
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, https://doi.org/10.5194/bg-17-5209-2020, https://doi.org/10.5194/bg-17-5209-2020, 2020
Short summary
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.
Benjamin Campforts, Veerle Vanacker, Frédéric Herman, Matthias Vanmaercke, Wolfgang Schwanghart, Gustavo E. Tenorio, Patrick Willems, and Gerard Govers
Earth Surf. Dynam., 8, 447–470, https://doi.org/10.5194/esurf-8-447-2020, https://doi.org/10.5194/esurf-8-447-2020, 2020
Short summary
Short summary
In this contribution, we explore the spatial determinants of bedrock river incision in the tropical Andes. The model results illustrate the problem of confounding between climatic and lithological variables, such as rock strength. Incorporating rock strength explicitly into river incision models strongly improves the explanatory power of all tested models and enables us to clarify the role of rainfall variability in controlling river incision rates.
Clare Woulds, James B. Bell, Adrian G. Glover, Steven Bouillon, and Louise S. Brown
Biogeosciences, 17, 1–12, https://doi.org/10.5194/bg-17-1-2020, https://doi.org/10.5194/bg-17-1-2020, 2020
Short summary
Short summary
Sedimented hydrothermal vents occur where heated, mineral-rich (hydrothermal) water seeps through seafloor sediments. They host chemosynthetic microbes, which use chemical energy to fix dissolved carbon dioxide into sugars (chemosynthesis). We conducted carbon tracing experiments, and observed chemosynthesis at both vent and non-vent sites. Thus, chemosynthesis occurred over a much larger area than expected, suggesting it is more widespread than previously thought.
Alberto V. Borges, François Darchambeau, Thibault Lambert, Cédric Morana, George H. Allen, Ernest Tambwe, Alfred Toengaho Sembaito, Taylor Mambo, José Nlandu Wabakhangazi, Jean-Pierre Descy, Cristian R. Teodoru, and Steven Bouillon
Biogeosciences, 16, 3801–3834, https://doi.org/10.5194/bg-16-3801-2019, https://doi.org/10.5194/bg-16-3801-2019, 2019
Short summary
Short summary
Tropical rivers might be strong sources of CO2 and CH4 to the atmosphere, although there is an enormous data gap. The origin of CO2 in lowland tropical rivers is not well characterized and can be from terra firme or from wetlands (flooded forests and aquatic macrophytes). We obtained a large field dataset of CO2, CH4 and N2O in the Congo, the second-largest river in the world, which allows us to quantity the emission of these greenhouse gases to the atmosphere and investigate their origin.
Trent R. Marwick, Fredrick Tamooh, Bernard Ogwoka, Alberto V. Borges, François Darchambeau, and Steven Bouillon
Biogeosciences, 15, 1683–1700, https://doi.org/10.5194/bg-15-1683-2018, https://doi.org/10.5194/bg-15-1683-2018, 2018
Short summary
Short summary
A 2-year biogeochemical record provides annual sediment and element flux estimates for the non-dammed Sabaki River, Kenya, establishing a baseline for future research in light of impending construction of the first major upstream reservoir. Over 80 % of material fluxes occur across the wet season, with annual yields comparable to the adjacent, and dammed, Tana River. Observations at low-flow periods suggest large mammalian herbivores may be vectors of terrestrial subsidies to the water column.
Alberto V. Borges, Gwenaël Abril, and Steven Bouillon
Biogeosciences, 15, 1093–1114, https://doi.org/10.5194/bg-15-1093-2018, https://doi.org/10.5194/bg-15-1093-2018, 2018
Short summary
Short summary
The Mekong River is among the largest on Earth and is vital for the economy of Vietnam and South East Asia and the livelihood of the local population (70 million across six countries). Numerous dams for hydropower are planned, which will affect the delivery of water and sediments to the Mekong delta, with numerous possible consequences. We report the dynamics of two greenhouse gases (CO2 and CH4) in the Mekong delta that can be used as a reference state to evaluate future changes.
Gerard Govers, Roel Merckx, Bas van Wesemael, and Kristof Van Oost
SOIL, 3, 45–59, https://doi.org/10.5194/soil-3-45-2017, https://doi.org/10.5194/soil-3-45-2017, 2017
Short summary
Short summary
We discuss pathways towards better soil protection in the 21st century. The efficacy of soil conservation technology is not a fundamental barrier for a more sustainable soil management. However, soil conservation is generally not directly beneficial to the farmer. We believe that the solution of this conundrum is a rapid, smart intensification of agriculture in the Global South. This will reduce the financial burden and will, at the same time, allow more effective conservation.
Naomi Geeraert, Fred O. Omengo, Fredrick Tamooh, Trent R. Marwick, Alberto V. Borges, Gerard Govers, and Steven Bouillon
Biogeosciences Discuss., https://doi.org/10.5194/bg-2017-31, https://doi.org/10.5194/bg-2017-31, 2017
Manuscript not accepted for further review
Short summary
Short summary
We observed that the relationship between the concentrations and the water discharge in the Tana River changed in wet seasons with and without flooding. Detailed sampling in those seasons is required in order to construct several rating curves and to obtain reliable flux estimates. The sediment and carbon fluxes in function of discharge will help us to asses the flux changes that can be expected when the hydrology changes due to climate change or human impact.
Marijn Van de Broek, Stijn Temmerman, Roel Merckx, and Gerard Govers
Biogeosciences, 13, 6611–6624, https://doi.org/10.5194/bg-13-6611-2016, https://doi.org/10.5194/bg-13-6611-2016, 2016
Short summary
Short summary
The results of this study on the organic carbon (OC) stocks of tidal marshes show that variations in OC stocks along estuaries are important and should be taken into account to make accurate estimates of the total amount of OC stored in these ecosystems. Moreover, our results clearly show that most studies underestimate the variation in OC stocks along estuaries due to a shallow sampling depth, neglecting the variation in OC decomposition after burial along estuaries.
Thibault Lambert, Steven Bouillon, François Darchambeau, Philippe Massicotte, and Alberto V. Borges
Biogeosciences, 13, 5405–5420, https://doi.org/10.5194/bg-13-5405-2016, https://doi.org/10.5194/bg-13-5405-2016, 2016
Short summary
Short summary
This paper aims to investigate the spatial variability in dissolved organic matter (DOM) in terms of both concentration and composition in the Congo River network. Stable carbon isotopes and absorption and fluorescent properties of DOM were used as proxies for DOM composition. This study shows that DOM degradation within the Congo Basin results in the transition from aromatic to aliphatic DOM as well as the role of landscape and water residence time on this transition.
Clare Woulds, Steven Bouillon, Gregory L. Cowie, Emily Drake, Jack J. Middelburg, and Ursula Witte
Biogeosciences, 13, 4343–4357, https://doi.org/10.5194/bg-13-4343-2016, https://doi.org/10.5194/bg-13-4343-2016, 2016
Short summary
Short summary
Estuarine sediments are important locations for carbon cycling and burial. We used tracer experiments to investigate how site conditions affect the way in which seafloor biological communities cycle carbon. We showed that while total respiration rates are primarily determined by temperature, total carbon processing by the biological community is strongly related to
its biomass. Further, we saw a distinct pattern of carbon cycling in sandy sediment, in which uptake by bacteria dominates.
Thibault Lambert, Cristian R. Teodoru, Frank C. Nyoni, Steven Bouillon, François Darchambeau, Philippe Massicotte, and Alberto V. Borges
Biogeosciences, 13, 2727–2741, https://doi.org/10.5194/bg-13-2727-2016, https://doi.org/10.5194/bg-13-2727-2016, 2016
Short summary
Short summary
This manuscript presents a detailed analysis of transport and transformation of dissolved organic matter along the Zambezi River and its largest tributary. A particular focus is put on the effects of floodplains/wetlands and reservoirs as well as low-flow vs. high-flow conditions on the longitudinal patterns in DOM concentration and composition. It is the first study to present such a detailed analysis for a whole, large river system, and in particular for a tropical river other than the Amazon.
N. Geeraert, F. O. Omengo, G. Govers, and S. Bouillon
Biogeosciences, 13, 517–525, https://doi.org/10.5194/bg-13-517-2016, https://doi.org/10.5194/bg-13-517-2016, 2016
Short summary
Short summary
Rivers transport a large amount of carbon as dissolved organic carbon (DOC). Our incubation experiments on water of the Tana River, Kenya, showed that microbial decomposition of 10–60 % of the initial DOC occurred within the first 24–48 h. Simultaneously, there was a decrease in isotopic composition, indicating that DOC derived from C4 vegetation is preferentially decomposed. This has implications for the assessment of vegetation in a catchment based on isotope signatures of riverine carbon.
C. Morana, F. Darchambeau, F. A. E. Roland, A. V. Borges, F. Muvundja, Z. Kelemen, P. Masilya, J.-P. Descy, and S. Bouillon
Biogeosciences, 12, 4953–4963, https://doi.org/10.5194/bg-12-4953-2015, https://doi.org/10.5194/bg-12-4953-2015, 2015
C. R. Teodoru, F. C. Nyoni, A. V. Borges, F. Darchambeau, I. Nyambe, and S. Bouillon
Biogeosciences, 12, 2431–2453, https://doi.org/10.5194/bg-12-2431-2015, https://doi.org/10.5194/bg-12-2431-2015, 2015
Short summary
Short summary
CO2 and CH4 concentrations and fluxes in the Zambezi River basin are well below the median/average values reported previously for tropical rivers, streams and reservoirs, and mainly controlled by the connectivity with floodplains and the presence of waterfalls and man-made reservoirs. The mass balance suggests that carbon transport to the ocean represents the major component (~60%) of the budget, while emissions to the atmosphere account for less than 40% of the total carbon yield.
C. Morana, A. V. Borges, F. A. E. Roland, F. Darchambeau, J.-P. Descy, and S. Bouillon
Biogeosciences, 12, 2077–2088, https://doi.org/10.5194/bg-12-2077-2015, https://doi.org/10.5194/bg-12-2077-2015, 2015
G. Abril, S. Bouillon, F. Darchambeau, C. R. Teodoru, T. R. Marwick, F. Tamooh, F. Ochieng Omengo, N. Geeraert, L. Deirmendjian, P. Polsenaere, and A. V. Borges
Biogeosciences, 12, 67–78, https://doi.org/10.5194/bg-12-67-2015, https://doi.org/10.5194/bg-12-67-2015, 2015
Short summary
Short summary
We compared pCO2 data calculated from pH and alkalinity from those measured directly in a large array of temperate and tropical freshwaters. This revealed a large overestimation (up to 300%) of calculated pCO2 in the case of acidic and organic-rich waters, due to a contribution of organic acids anions to alkalinity and a lower buffering capacity of the carbonate system at acidic pH. Given the widespread distribution of acidic freshwaters, direct measurements of water pCO2 are encouraged.
T. R. Marwick, F. Tamooh, B. Ogwoka, C. Teodoru, A. V. Borges, F. Darchambeau, and S. Bouillon
Biogeosciences, 11, 443–460, https://doi.org/10.5194/bg-11-443-2014, https://doi.org/10.5194/bg-11-443-2014, 2014
F. Tamooh, A. V. Borges, F. J. R. Meysman, K. Van Den Meersche, F. Dehairs, R. Merckx, and S. Bouillon
Biogeosciences, 10, 6911–6928, https://doi.org/10.5194/bg-10-6911-2013, https://doi.org/10.5194/bg-10-6911-2013, 2013
Related subject area
Biogeochemistry: Rivers & Streams
Seasonal particulate organic carbon dynamics of the Kolyma River tributaries, Siberia
Geomorphologic controls and anthropogenic impacts on dissolved organic carbon from mountainous rivers: insights from optical properties and carbon isotopes
Alkalinity generation from carbonate weathering in a silicate-dominated headwater catchment at Iskorasfjellet, northern Norway
Physical and stoichiometric controls on stream respiration in a headwater stream
Local processes with a global impact: unraveling the dynamics of gas evasion in a step-and-pool configuration
Complex dissolved organic matter (DOM) on the roof of the world – Tibetan DOM molecular characteristics indicate sources, land use effects, and processing along the fluvial–limnic continuum
Maximum respiration rates in hyporheic zone sediments are primarily constrained by organic carbon concentration and secondarily by organic matter chemistry
Glacier loss and vegetation expansion alter organic and inorganic carbon dynamics in high-mountain streams
Particulate organic matter in the Lena River and its delta: from the permafrost catchment to the Arctic Ocean
Stable isotopic evidence for the excess leaching of unprocessed atmospheric nitrate from forested catchments under high nitrogen saturation
Nitrogen isotopes reveal a particulate-matter-driven biogeochemical reactor in a temperate estuary
High-resolution vertical biogeochemical profiles in the hyporheic zone reveal insights into microbial methane cycling
Organic matter transformations are disconnected between surface water and the hyporheic zone
CO2 emissions from peat-draining rivers regulated by water pH
Effects of peatland management on aquatic carbon concentrations and fluxes
Resistance and resilience of stream metabolism to high flow disturbances
Enhanced bioavailability of dissolved organic matter (DOM) in human-disturbed streams in Alpine fluvial networks
Spatial and temporal variability of pCO2 and CO2 emissions from the Dong River in south China
Fluvial carbon dioxide emission from the Lena River basin during the spring flood
Diel patterns in stream nitrate concentration produced by in-stream processes
Complex interactions of in-stream dissolved organic matter and nutrient spiralling unravelled by Bayesian regression analysis
Spatial–temporal variations in riverine carbon strongly influenced by local hydrological events in an alpine catchment
Increased carbon capture by a silicate-treated forested watershed affected by acid deposition
Thermokarst amplifies fluvial inorganic carbon cycling and export across watershed scales on the Peel Plateau, Canada
Temporary and net sinks of atmospheric CO2 due to chemical weathering in subtropical catchment with mixing carbonate and silicate lithology
From canals to the coast: dissolved organic matter and trace metal composition in rivers draining degraded tropical peatlands in Indonesia
Distribution and flux of dissolved iron in the peatland-draining rivers and estuaries of Sarawak, Malaysian Borneo
Comparisons of dissolved organic matter and its optical characteristics in small low and high Arctic catchments
High-frequency measurements explain quantity and quality of dissolved organic carbon mobilization in a headwater catchment
Dissolved inorganic nitrogen in a tropical estuary in Malaysia: transport and transformation
Behaviour of Dissolved Phosphorus with the associated nutrients in relation to phytoplankton biomass of the Rajang River-South China Sea continuum
Synchrony in catchment stream colour levels is driven by both local and regional climate
The post-monsoon carbon biogeochemistry of the Hooghly–Sundarbans estuarine system under different levels of anthropogenic impacts
Riverine particulate C and N generated at the permafrost thaw front: case study of western Siberian rivers across a 1700 km latitudinal transect
Geochemistry of the dissolved loads during high-flow season of rivers in the southeastern coastal region of China: anthropogenic impact on chemical weathering and carbon sequestration
CO2 partial pressure and CO2 emission along the lower Red River (Vietnam)
Stable isotopes of nitrate reveal different nitrogen processing mechanisms in streams across a land use gradient during wet and dry periods
Riverine carbon export in the arid to semiarid Wuding River catchment on the Chinese Loess Plateau
Use of argon to measure gas exchange in turbulent mountain streams
Reviews and syntheses: Anthropogenic perturbations to carbon fluxes in Asian river systems – concepts, emerging trends, and research challenges
Shifts in stream hydrochemistry in responses to typhoon and non-typhoon precipitation
QUAL-NET, a high temporal-resolution eutrophication model for large hydrographic networks
Diel fluctuations of viscosity-driven riparian inflow affect streamflow DOC concentration
A comprehensive biogeochemical record and annual flux estimates for the Sabaki River (Kenya)
Hydro-ecological controls on dissolved carbon dynamics in groundwater and export to streams in a temperate pine forest
Regional-scale lateral carbon transport and CO2 evasion in temperate stream catchments
Carbon and nutrient export regimes from headwater catchments to downstream reaches
Influence of infrastructure on water quality and greenhouse gas dynamics in urban streams
Hydromorphological restoration stimulates river ecosystem metabolism
Quantifying nutrient fluxes with a new hyporheic passive flux meter (HPFM)
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
Biogeosciences, 21, 357–379, https://doi.org/10.5194/bg-21-357-2024, https://doi.org/10.5194/bg-21-357-2024, 2024
Short summary
Short summary
Permafrost thaw releases organic carbon into waterways. Decomposition of this carbon pool emits greenhouse gases into the atmosphere, enhancing climate warming. We show that Arctic river carbon and water chemistry are different between the spring ice breakup and summer and that primary production is initiated in small Arctic rivers right after ice breakup, in contrast to in large rivers. This may have implications for fluvial carbon dynamics and greenhouse gas uptake and emission balance.
Shuai Chen, Jun Zhong, Lishan Ran, Yuanbi Yi, Wanfa Wang, Zelong Yan, Si-liang Li, and Khan M. G. Mostofa
Biogeosciences, 20, 4949–4967, https://doi.org/10.5194/bg-20-4949-2023, https://doi.org/10.5194/bg-20-4949-2023, 2023
Short summary
Short summary
This study found the source of dissolved organic carbon and its optical properties (e.g., aromaticity, humification) are related to human land use and catchment slope in anthropogenically impacted subtropical mountainous rivers. The study highlights that the combination of dual carbon isotopes and optical properties represents a useful tool in tracing the origin of dissolved organic carbon and its in-stream processes.
Nele Lehmann, Hugues Lantuit, Michael Ernst Böttcher, Jens Hartmann, Antje Eulenburg, and Helmuth Thomas
Biogeosciences, 20, 3459–3479, https://doi.org/10.5194/bg-20-3459-2023, https://doi.org/10.5194/bg-20-3459-2023, 2023
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Trent R. Marwick, Fredrick Tamooh, Bernard Ogwoka, Alberto V. Borges, François Darchambeau, and Steven Bouillon
Biogeosciences, 15, 1683–1700, https://doi.org/10.5194/bg-15-1683-2018, https://doi.org/10.5194/bg-15-1683-2018, 2018
Short summary
Short summary
A 2-year biogeochemical record provides annual sediment and element flux estimates for the non-dammed Sabaki River, Kenya, establishing a baseline for future research in light of impending construction of the first major upstream reservoir. Over 80 % of material fluxes occur across the wet season, with annual yields comparable to the adjacent, and dammed, Tana River. Observations at low-flow periods suggest large mammalian herbivores may be vectors of terrestrial subsidies to the water column.
Loris Deirmendjian, Denis Loustau, Laurent Augusto, Sébastien Lafont, Christophe Chipeaux, Dominique Poirier, and Gwenaël Abril
Biogeosciences, 15, 669–691, https://doi.org/10.5194/bg-15-669-2018, https://doi.org/10.5194/bg-15-669-2018, 2018
Short summary
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.
Katrin Magin, Celia Somlai-Haase, Ralf B. Schäfer, and Andreas Lorke
Biogeosciences, 14, 5003–5014, https://doi.org/10.5194/bg-14-5003-2017, https://doi.org/10.5194/bg-14-5003-2017, 2017
Short summary
Short summary
We analyzed the relationship between terrestrial net primary production (NPP) and the rate at which carbon is exported from catchments in a temperate stream network. The carbon exported by streams and rivers corresponds to 2.7 % of the terrestrial NPP. CO2 evasion and downstream transport contribute about equally to this flux. A review of existing studies suggests that the catchment-specific carbon export varies in a relatively narrow range across different study regions and spatial scales.
Rémi Dupas, Andreas Musolff, James W. Jawitz, P. Suresh C. Rao, Christoph G. Jäger, Jan H. Fleckenstein, Michael Rode, and Dietrich Borchardt
Biogeosciences, 14, 4391–4407, https://doi.org/10.5194/bg-14-4391-2017, https://doi.org/10.5194/bg-14-4391-2017, 2017
Short summary
Short summary
Carbon and nutrient export regimes were analyzed from archetypal headwater catchments to
downstream reaches. In headwater catchments, land use and lithology determine
land-to-stream C, N and P transfer processes. The crucial role of riparian
zones in C, N and P coupling was investigated. In downstream reaches,
point-source contributions and in-stream processes alter C, N and P export
regimes.
Rose M. Smith, Sujay S. Kaushal, Jake J. Beaulieu, Michael J. Pennino, and Claire Welty
Biogeosciences, 14, 2831–2849, https://doi.org/10.5194/bg-14-2831-2017, https://doi.org/10.5194/bg-14-2831-2017, 2017
Short summary
Short summary
Urban streams receive excess nitrogen from numerous sources. We hypothesized that variations in carbon availability and subsurface infrastructure influence emissions of N2O and other greenhouse gases (CH4 and CO2) as excess N is utilized by microbes. We sampled eight streams draining four categories of stormwater and sanitary infrastructure. Dissolved nitrogen concentration was the strongest predictor of CO2 and N2O concentrations, while C : N ratio was the strongest predictor of CH4 in streams.
Benjamin Kupilas, Daniel Hering, Armin W. Lorenz, Christoph Knuth, and Björn Gücker
Biogeosciences, 14, 1989–2002, https://doi.org/10.5194/bg-14-1989-2017, https://doi.org/10.5194/bg-14-1989-2017, 2017
Short summary
Short summary
Modern ecosystem restoration should consider a wide range of environmental characteristics, including functional ones, such as rates and patterns of ecosystem metabolism. We show that hydromorphological river restoration enhanced habitat availability and abundance of macrophytes, promoting river primary productivity and respiration. Incorporating ecosystem functioning into monitoring programs enables a more holistic assessment of river health and a better understanding of restoration effects.
Julia Vanessa Kunz, Michael D. Annable, Jaehyun Cho, Wolf von Tümpling, Kirk Hatfield, Suresh Rao, Dietrich Borchardt, and Michael Rode
Biogeosciences, 14, 631–649, https://doi.org/10.5194/bg-14-631-2017, https://doi.org/10.5194/bg-14-631-2017, 2017
Short summary
Short summary
The hyporheic zone, the subsurface region of streams, is a key compartment for in-stream nutrient retention. Knowledge on actual hyporheic processing rates is still limited due to methodological restrictions which are mainly related to the high local and temporal variability of subsurface flow patterns and nutrient transformation processes. We present a new device which allows quantitative assessment of hyporheic nutrient fluxes and demonstrate its advantages in an exemplary field testing.
Cited articles
Angst, G., Mueller, C. W., Prater, I., Angst, Š., Frouz, J.,
Jílková, V., Peterse, F., and Nierop, K. G. J.: Earthworms act as
biochemical reactors to convert labile plant compounds into stabilized soil
microbial necromass, Commun. Biol., 2, 1–7,
https://doi.org/10.1038/s42003-019-0684-z, 2019.
Aufdenkampe, A. K., Mayorga, E., Raymond, P. A., Melack, J. M., Doney, S.
C., Alin, S. R., Aalto, R. E., and Yoo, K.: Riverine coupling of
biogeochemical cycles between land, oceans, and atmosphere, Front. Ecol.
Environ., 9, 53–60, https://doi.org/10.1890/100014, 2011.
Berggren, M., Laudon, H., Jonsson, A., and Jansson, M.: Nutrient constraints
on metabolism affect the temperature regulation of aquatic bacterial growth
efficiency, Microb. Ecol., 60, 894–902,
https://doi.org/10.1007/s00248-010-9751-1, 2010.
Berggren, M., Lapierre, J. F., and Del Giorgio, P. A.: Magnitude and
regulation of bacterioplankton respiratory quotient across freshwater
environmental gradients, ISME J., 6, 984–993,
https://doi.org/10.1038/ismej.2011.157, 2012.
Bianchi, T. S.: The role of terrestrially derived organic carbon in the
coastal ocean: A changing paradigm and the priming effect, Proc. Natl. Acad.
Sci., 108, 19473–19481, https://doi.org/10.1073/pnas.1017982108, 2011.
Broothaerts, N., Verstraeten, G., Kasse, C., Bohncke, S., Notebaert, B., and
Vandenberghe, J.: From natural to human-dominated floodplain geoecology – A
Holocene perspective for the Dijle catchment, Belgium, Anthropocene, 8,
46–58, https://doi.org/10.1016/j.ancene.2014.12.001, 2014.
Butman, D. and Raymond, P. A.: Significant efflux of carbon dioxide from
streams and rivers in the United States, Nat. Geosci., 4, 839–842,
https://doi.org/10.1038/ngeo1294, 2011.
Cleveland, C. C., Nemergut, D. R., Schmidt, S. K., and Townsend, A. R.:
Increases in soil respiration following labile carbon additions linked to
rapid shifts in soil microbial community composition, Biogeochemistry,
82, 229–240, https://doi.org/10.1007/s10533-006-9065-z, 2007.
Cole, J. J. and Caraco, N. F.: Carbon in catchments: Connecting terrestrial
carbon losses with aquatic metabolism, Mar. Freshw. Res., 52, 101–110,
https://doi.org/10.1071/mf00084, 2001.
Cole, J. J., Prairie, Y. T., Caraco, N. F., McDowell, W. H., Tranvik, L. J.,
Striegl, R. G., Duarte, C. M., Kortelainen, P., Downing, J. A., Middelburg,
J. J., and Melack, J.: Plumbing the global carbon cycle: Integrating inland
waters into the terrestrial carbon budget, Ecosystems, 10, 172–185,
https://doi.org/10.1007/s10021-006-9013-8, 2007.
Dodds, W. K. and Cole, J. J.: Expanding the concept of trophic state in
aquatic ecosystems: It's not just the autotrophs, Aquat. Sci., 69,
427–439, https://doi.org/10.1007/s00027-007-0922-1, 2007.
FAO: World Reference Base for Soil Resources, World Soil Resources Reports
84, Food and Agriculture Organization of the United Nations, Rome, https://doi.org/10.1108/09504121011021959, 1998.
Gajic, B., Dugalic, G., and Djurovic, N.: Comparison of soil organic matter
content, aggregate composition and water stability of gleyic fluvisol from
adjacent forest and cultivated areas, Agron. Res., 4, 499–508, 2006.
Gillabel, J., Cebrian-Lopez, B., Six, J., and Merckx, R.: Experimental
evidence for the attenuating effect of SOM protection on temperature
sensitivity of SOM decomposition, Glob. Chang. Biol., 16, 2789–2798,
https://doi.org/10.1111/j.1365-2486.2009.02132.x, 2010.
Govers, G.: Rill Erosion on Arable Land in Central Belgium: Rates, Controls
and Predictability, Catena, 18, 133–155,
https://doi.org/10.1016/0341-8162(91)90013-n, 1991.
Göl, C.: The effects of land use change on soil properties and organic
carbon at Dagdami river catchment in Turkey, J. Environ. Biol., 30,
825–830, 2009.
Gudasz, C., Sobek, S., Bastviken, D., Koehler, B., and Tranvik, L. J.:
Temperature sensitivity of organic carbon mineralization in contrasting lake
sediments, J. Geophys. Res.-Biogeosci., 120, 1215–1225,
https://doi.org/10.1002/2015jg002928, 2015.
Guenet, B., Danger, M., Harrault, L., Allard, B., Jauset-Alcala, M.,
Bardoux, G., Benest, D., Abbadie, L., and Lacroix, G.: Fast mineralization of
land-born C in inland waters: First experimental evidences of aquatic
priming effect, Hydrobiologia, 721, 35–44,
https://doi.org/10.1007/s10750-013-1635-1, 2014.
Hu, Y., Xiang, D., Veresoglou, S. D., Chen, F., Chen, Y., Hao, Z., Zhang, X.,
and Chen, B.: Soil organic carbon and soil structure are driving microbial
abundance and community composition across the arid and semi-arid grasslands
in northern China, Soil Biol. Biochem., 77, 51–57,
https://doi.org/10.1016/j.soilbio.2014.06.014, 2014.
Kling, G. W.: Land-water interactions: the influence of terrestrial
diversity on aquatic ecosystems, in: Arctic and Alpine Biodiversity:
Patterns, Causes and Ecosystem Consequences, edited by: Chapin, F. S. and
Körner, C., Springer, Berlin and Heidelberg, Germany, 297–310,
https://doi.org/10.1007/978-3-642-78966-3, 1995.
Kögel-Knabner, I.: The macromolecular organic composition of plant and
microbial residues as inputs to soil organic matter, Soil Biol. Biochem.,
34, 139–162, https://doi.org/10.1016/s0038-0717(01)00158-4, 2002.
Koehler, B., Von Wachenfeldt, E., Kothawala, D., and Tranvik, L. J.:
Reactivity continuum of dissolved organic carbon decomposition in lake
water, J. Geophys. Res.-Biogeosci., 117, G01024,
https://doi.org/10.1029/2011jg001793, 2012.
Lal, R.: Soil erosion and the global carbon budget, Environ. Int., 29,
437–450, https://doi.org/10.1016/S0160-4120(02)00192-7, 2003.
Lapierre, J. F., Guillemette, F., Berggren, M., and Del Giorgio, P. A.:
Increases in terrestrially derived carbon stimulate organic carbon
processing and CO2 emissions in boreal aquatic ecosystems, Nat.
Commun., 4, 1–7, https://doi.org/10.1038/ncomms3972, 2013.
Le Bissonnais, Y. L.: Aggregate stability and assessment of soil
crustability and erodibility: I. Theory and methodology, Eur. J. Soil Sci.,
47, 425–437, https://doi.org/10.1111/j.1365-2389.1996.tb01843.x, 1996.
Lennon, J. T. and Pfaff, L. E.: Source and supply of terrestrial organic
matter affects aquatic microbial metabolism, Aquat. Microb. Ecol., 39,
107–119, https://doi.org/10.3354/ame039107, 2005.
Li, J., Wu, X., Gebremikael, M. T., Wu, H., Cai, D., Wang, B., Li, B.,
Zhang, J., Li, Y., and Xi, J.: Response of soil organic carbon fractions,
microbial community composition and carbon mineralization to high-input
fertilizer practices under an intensive agricultural system, PLoS One,
13, e0195144, https://doi.org/10.1371/journal.pone.0195144, 2018.
Liang, X., Yuan, J., Yang, E., and Meng, J.: Responses of soil organic carbon
decomposition and microbial community to the addition of plant residues with
different C : N ratio, Eur. J. Soil Biol., 82, 50–55,
https://doi.org/10.1016/j.ejsobi.2017.08.005, 2017.
Marín-Spiotta, E., Gruley, K. E., Crawford, J., Atkinson, E. E., Miesel, J.
R., Greene, S., Cardona-Correa, C., and Spencer, R. G.: Paradigm shifts in soil
organic matter research affect interpretations of aquatic carbon cycling:
transcending disciplinary and ecosystem boundaries, Biogeochemistry,
117, 279–297, https://doi.org/10.1007/s10533-013-9949-7, 2014.
Marwick, T. R., Tamooh, F., Teodoru, C. R., Borges, A. V, Darchambeau, F.,
and Bouillon, S.: The age of river-transported carbon: a global perspective,
Global Biogeochem. Cy., 29, 122–137,
https://doi.org/10.1002/2014gb004911, 2015.
Mayorga, E., Aufdenkampe, A. K., Masiello, C. A., Krusche, A. V., Hedges, J.
I., Quay, P. D., Richey, J. E., and Brown, T. A.: Young organic matter as a
source of carbon dioxide outgassing from Amazonian rivers, Nature,
436, 538–541, https://doi.org/10.1038/nature03880, 2005.
McCallister, S. L. and Del Giorgio, P. A.: Evidence for the respiration of
ancient terrestrial organic C in northern temperate lakes and streams, Proc.
Natl. Acad. Sci., 109, 16963–16968,
https://doi.org/10.1073/pnas.1207305109, 2012.
Raymond, P. A. and Bauer, J. E.: Riverine export of aged terrestrial organic
matter to the North Atlantic Ocean, Nature, 409, 497–500,
https://doi.org/10.1038/35054034, 2001.
Richardson, D. C., Newbold, J. D., Aufdenkampe, A. K., Taylor, P. G., and
Kaplan, L. A.: Measuring heterotrophic respiration rates of suspended
particulate organic carbon from stream ecosystems, Limnol. Oceanogr., 11, 247–261, https://doi.org/10.4319/lom.2013.11.247, 2013.
Rosenheim, B. E., Roe, K. M., Roberts, B. J., Kolker, A. S., Allison, M. A.,
and Johannesson, K. H.: River discharge influences on particulate organic
carbon age structure in the Mississippi/Atchafalaya River System, Global
Biogeochem. Cy., 27, 154–166, https://doi.org/10.1002/gbc.20018,
2013.
Schmidt, M. W. I., Torn, M. S., Abiven, S., Dittmar, T., Guggenberger, G.,
Janssens, I. A., Kleber, M., Kögel-Knabner, I., Lehmann, J., Manning, D.
A. C., Nannipieri, P., Rasse, D. P., Weiner, S., and Trumbore, S. E.:
Persistence of soil organic matter as an ecosystem property, Nature,
478, 49–56, https://doi.org/10.1038/nature10386, 2011.
Spencer, R. G. M., Stubbins, A., Hernes, P. J., Baker, A., Mopper, K.,
Aufdenkampe, A. K., Dyda, R. Y., Mwamba, V. L., Mangangu, A. M.,
Wabakanghanzi, J. N., and Six, J.: Photochemical degradation of dissolved
organic matter and dissolved lignin phenols from the Congo River, J.
Geophys. Res.-Biogeosci., 114, G03010, https://doi.org/10.1029/2009jg000968,
2009.
Takken, I., Beuselinck, L., Nachtergaele, J., Govers, G., Poesen, J., and
Degraer, G.: Spatial evaluation of a physically-based distributed erosion
model (LISEM), Catena, 37, 431–447,
https://doi.org/10.1016/s0341-8162(99)00031-4, 1999.
Tian, Q., Yang, X., Wang, X., Liao, C., Li, Q., and Wang, M.: Microbial
community mediated response of organic carbon mineralization to labile
carbon and nitrogen addition in topsoil and subsoil, Biogeochemistry,
128, 125–139, https://doi.org/10.1007/s10533-016-0198-4, 2016.
Trumbore, S.: Age of soil organic matter and soil respiration: Radiocarbon
constraints on belowground C dynamics, Ecol. Appl., 10, 399–411,
https://doi.org/10.1890/1051-0761(2000)010[0399:aosoma]2.0.co;2, 2000.
Ward, N. D., Keil, R. G., Medeiros, P. M., Brito, D. C., Cunha, A. C.,
Dittmar, T., Yager, P. L., Krusche, A. V., and Richey, J. E.: Degradation of
terrestrially derived macromolecules in the Amazon River, Nat. Geosci.,
6, 530–533, https://doi.org/10.1038/ngeo1817, 2013.
Ward, N. D., Bianchi, T. S., Medeiros, P. M., Seidel, M., Richey, J. E.,
Keil, R. G., and Sawakuchi, H. O.: Where Carbon Goes When Water Flows: Carbon
Cycling across the Aquatic Continuum, Front. Mar. Sci., 4, 7,
https://doi.org/10.3389/fmars.2017.00007, 2017.
Ward, N. D., Sawakuchi, H. O., Neu, V., Less, D. F. S., Valerio, A. M.,
Cunha, A. C., Kampel, M., Bianchi, T. S., Krusche, A. V., Richey, J. E., and
Keil, R. G.: Velocity-amplified microbial respiration rates in the lower
Amazon River, Limnol. Oceanogr. Lett., 3, 265–274,
https://doi.org/10.1002/lol2.10062, 2018.
Ward, N. D., Sawakuchi, H. O., Richey, J. E., Keil, R. G., and Bianchi, T.
S.: Enhanced Aquatic Respiration Associated With Mixing of Clearwater
Tributary and Turbid Amazon River Waters, Front. Earth Sci., 7, 1–6,
https://doi.org/10.3389/feart.2019.00101, 2019a.
Ward, N. D., Morrison, E. S., Liu, Y., Rivas-Ubach, A., Osborne, T. Z.,
Ogram, A. V., and Bianchi, T. S.: Marine microbial community responses
related to wetland carbon mobilization in the coastal zone, Limnol.
Oceanogr. Lett., 4, 25–33, https://doi.org/10.1002/lol2.10101, 2019b.
Weyhenmeyer, G. A., Fröberg, M., Karltun, E., Khalili, M., Kothawala,
D., Temnerud, J., and Tranvik, L. J.: Selective decay of terrestrial organic
carbon during transport from land to sea, Glob. Change Biol., 18,
349–355, https://doi.org/10.1111/j.1365-2486.2011.02544.x, 2012.
Wilkinson, G. M., Pace, M. L., and Cole, J. J.: Terrestrial dominance of
organic matter in north temperate lakes, Global Biogeochem. Cy., 27,
43–51, https://doi.org/10.1029/2012gb004453, 2013.
Wu, X., Wu, L., Liu, Y., Zhang, P., Li, Q., Zhou, J., Hess, N. J., Hazen, T.
C., Yang, W., and Chakraborty, R.: Microbial interactions with dissolved
organic matter drive carbon dynamics and community succession, Front.
Microbiol., 9, 1234, https://doi.org/10.3389/fmicb.2018.01234, 2018.
Short summary
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.
We investigate the relative importance of two individual factors (hydrodynamical disturbance and...
Altmetrics
Final-revised paper
Preprint