Articles | Volume 20, issue 15
https://doi.org/10.5194/bg-20-3151-2023
© Author(s) 2023. 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-20-3151-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
01 Aug 2023
Research article |
| 01 Aug 2023
| 01 Aug 2023
How well does ramped thermal oxidation quantify the age distribution of soil carbon? Assessing thermal stability of physically and chemically fractionated soil organic matter
Biogeochemical Processes Department, Max Planck Institute for
Biogeochemistry, 07745 Jena, Germany
Department of Environmental Systems Science, ETH Zürich,
8092 Zurich, Switzerland
Marion Schrumpf
Biogeochemical Processes Department, Max Planck Institute for
Biogeochemistry, 07745 Jena, Germany
Alison Hoyt
Earth System Science, Stanford University, Stanford, CA 94305, USA
Carlos A. Sierra
Biogeochemical Processes Department, Max Planck Institute for
Biogeochemistry, 07745 Jena, Germany
Department of Ecology, Swedish University of Agricultural Sciences,
Uppsala, 750 07, Sweden
Sebastian Doetterl
Department of Environmental Systems Science, ETH Zürich,
8092 Zurich, Switzerland
Valier Galy
Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
Susan Trumbore
Biogeochemical Processes Department, Max Planck Institute for
Biogeochemistry, 07745 Jena, Germany
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Manuscript not accepted for further review
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Andrea Scheibe, Carlos A. Sierra, and Marie Spohn
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Lin Yu, Silvia Caldararu, Bernhard Ahrens, Thomas Wutzler, Marion Schrumpf, Julian Helfenstein, Chiara Pistocchi, and Sönke Zaehle
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Thomas Wutzler, Lin Yu, Marion Schrumpf, and Sönke Zaehle
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Jeffrey Prescott Beem-Miller, Craig Rasmussen, Alison May Hoyt, Marion Schrumpf, Georg Guggenberger, and Susan Trumbore
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Preprint withdrawn
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Rachael Akinyede, Martin Taubert, Marion Schrumpf, Susan Trumbore, and Kirsten Küsel
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Carlos A. Sierra, Verónika Ceballos-Núñez, Henrik Hartmann, David Herrera-Ramírez, and Holger Metzler
Biogeosciences, 19, 3727–3738, https://doi.org/10.5194/bg-19-3727-2022, https://doi.org/10.5194/bg-19-3727-2022, 2022
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Empirical work that estimates the age of respired CO2 from vegetation tissue shows that it may take from years to decades to respire previously produced photosynthates. However, many ecosystem models represent respiration processes in a form that cannot reproduce these observations. In this contribution, we attempt to provide compelling evidence, based on recent research, with the aim to promote a change in the predominant paradigm implemented in ecosystem models.
Agustín Sarquis, Ignacio Andrés Siebenhart, Amy Theresa Austin, and Carlos A. Sierra
Earth Syst. Sci. Data, 14, 3471–3488, https://doi.org/10.5194/essd-14-3471-2022, https://doi.org/10.5194/essd-14-3471-2022, 2022
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Moritz Mainka, Laura Summerauer, Daniel Wasner, Gina Garland, Marco Griepentrog, Asmeret Asefaw Berhe, and Sebastian Doetterl
Biogeosciences, 19, 1675–1689, https://doi.org/10.5194/bg-19-1675-2022, https://doi.org/10.5194/bg-19-1675-2022, 2022
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The largest share of terrestrial carbon is stored in soils, making them highly relevant as regards global change. Yet, the mechanisms governing soil carbon stabilization are not well understood. The present study contributes to a better understanding of these processes. We show that qualitative changes in soil organic matter (SOM) co-vary with alterations of the soil matrix following soil weathering. Hence, the type of SOM that is stabilized in soils might change as soils develop.
Pengzhi Zhao, Daniel Joseph Fallu, Sara Cucchiaro, Paolo Tarolli, Clive Waddington, David Cockcroft, Lisa Snape, Andreas Lang, Sebastian Doetterl, Antony G. Brown, and Kristof Van Oost
Biogeosciences, 18, 6301–6312, https://doi.org/10.5194/bg-18-6301-2021, https://doi.org/10.5194/bg-18-6301-2021, 2021
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We investigate the factors controlling the soil organic carbon (SOC) stability and temperature sensitivity of abandoned prehistoric agricultural terrace soils. Results suggest that the burial of former topsoil due to terracing provided an SOC stabilization mechanism. Both the soil C : N ratio and SOC mineral protection regulate soil SOC temperature sensitivity. However, which mechanism predominantly controls SOC temperature sensitivity depends on the age of the buried terrace soils.
Laura Summerauer, Philipp Baumann, Leonardo Ramirez-Lopez, Matti Barthel, Marijn Bauters, Benjamin Bukombe, Mario Reichenbach, Pascal Boeckx, Elizabeth Kearsley, Kristof Van Oost, Bernard Vanlauwe, Dieudonné Chiragaga, Aimé Bisimwa Heri-Kazi, Pieter Moonen, Andrew Sila, Keith Shepherd, Basile Bazirake Mujinya, Eric Van Ranst, Geert Baert, Sebastian Doetterl, and Johan Six
SOIL, 7, 693–715, https://doi.org/10.5194/soil-7-693-2021, https://doi.org/10.5194/soil-7-693-2021, 2021
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We present a soil mid-infrared library with over 1800 samples from central Africa in order to facilitate soil analyses of this highly understudied yet critical area. Together with an existing continental library, we demonstrate a regional analysis and geographical extrapolation to predict total carbon and nitrogen. Our results show accurate predictions and highlight the value that the data contribute to existing libraries. Our library is openly available for public use and for expansion.
Benjamin Bukombe, Peter Fiener, Alison M. Hoyt, Laurent K. Kidinda, and Sebastian Doetterl
SOIL, 7, 639–659, https://doi.org/10.5194/soil-7-639-2021, https://doi.org/10.5194/soil-7-639-2021, 2021
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Through a laboratory incubation experiment, we investigated the spatial patterns of specific maximum heterotrophic respiration in tropical African mountain forest soils developed from contrasting parent material along slope gradients. We found distinct differences in soil respiration between soil depths and geochemical regions related to soil fertility and the chemistry of the soil solution. The topographic origin of our samples was not a major determinant of the observed rates of respiration.
Sebastian Doetterl, Rodrigue K. Asifiwe, Geert Baert, Fernando Bamba, Marijn Bauters, Pascal Boeckx, Benjamin Bukombe, Georg Cadisch, Matthew Cooper, Landry N. Cizungu, Alison Hoyt, Clovis Kabaseke, Karsten Kalbitz, Laurent Kidinda, Annina Maier, Moritz Mainka, Julia Mayrock, Daniel Muhindo, Basile B. Mujinya, Serge M. Mukotanyi, Leon Nabahungu, Mario Reichenbach, Boris Rewald, Johan Six, Anna Stegmann, Laura Summerauer, Robin Unseld, Bernard Vanlauwe, Kristof Van Oost, Kris Verheyen, Cordula Vogel, Florian Wilken, and Peter Fiener
Earth Syst. Sci. Data, 13, 4133–4153, https://doi.org/10.5194/essd-13-4133-2021, https://doi.org/10.5194/essd-13-4133-2021, 2021
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Mario Reichenbach, Peter Fiener, Gina Garland, Marco Griepentrog, Johan Six, and Sebastian Doetterl
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In deeply weathered tropical rainforest soils of Africa, we found that patterns of soil organic carbon stocks differ between soils developed from geochemically contrasting parent material due to differences in the abundance of organo-mineral complexes, the presence/absence of chemical stabilization mechanisms of carbon with minerals and the presence of fossil organic carbon from sedimentary rocks. Physical stabilization mechanisms by aggregation provide additional protection of soil carbon.
Joseph Tamale, Roman Hüppi, Marco Griepentrog, Laban Frank Turyagyenda, Matti Barthel, Sebastian Doetterl, Peter Fiener, and Oliver van Straaten
SOIL, 7, 433–451, https://doi.org/10.5194/soil-7-433-2021, https://doi.org/10.5194/soil-7-433-2021, 2021
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Soil greenhouse gas (GHG) fluxes were measured monthly from nitrogen (N), phosphorous (P), N and P, and control plots of the first nutrient manipulation experiment located in an African pristine tropical forest using static chambers. The results suggest (1) contrasting soil GHG responses to nutrient addition, hence highlighting the complexity of the tropical forests, and (2) that the feedback of tropical forests to the global soil GHG budget could be altered by changes in N and P availability.
Florian Wilken, Peter Fiener, Michael Ketterer, Katrin Meusburger, Daniel Iragi Muhindo, Kristof van Oost, and Sebastian Doetterl
SOIL, 7, 399–414, https://doi.org/10.5194/soil-7-399-2021, https://doi.org/10.5194/soil-7-399-2021, 2021
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This study demonstrates the usability of fallout radionuclides 239Pu and 240Pu as a tool to assess soil degradation processes in tropical Africa, which is particularly valuable in regions with limited infrastructure and challenging monitoring conditions for landscape-scale soil degradation monitoring. The study shows no indication of soil redistribution in forest sites but substantial soil redistribution in cropland (sedimentation >40 cm in 55 years) with high variability.
Sophie F. von Fromm, Alison M. Hoyt, Markus Lange, Gifty E. Acquah, Ermias Aynekulu, Asmeret Asefaw Berhe, Stephan M. Haefele, Steve P. McGrath, Keith D. Shepherd, Andrew M. Sila, Johan Six, Erick K. Towett, Susan E. Trumbore, Tor-G. Vågen, Elvis Weullow, Leigh A. Winowiecki, and Sebastian Doetterl
SOIL, 7, 305–332, https://doi.org/10.5194/soil-7-305-2021, https://doi.org/10.5194/soil-7-305-2021, 2021
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We investigated various soil and climate properties that influence soil organic carbon (SOC) concentrations in sub-Saharan Africa. Our findings indicate that climate and geochemistry are equally important for explaining SOC variations. The key SOC-controlling factors are broadly similar to those for temperate regions, despite differences in soil development history between the two regions.
Marion Schrumpf, Klaus Kaiser, Allegra Mayer, Günter Hempel, and Susan Trumbore
Biogeosciences, 18, 1241–1257, https://doi.org/10.5194/bg-18-1241-2021, https://doi.org/10.5194/bg-18-1241-2021, 2021
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A large amount of organic carbon (OC) in soil is protected against decay by bonding to minerals. We studied the release of mineral-bonded OC by NaF–NaOH extraction and H2O2 oxidation. Unexpectedly, extraction and oxidation removed mineral-bonded OC at roughly constant portions and of similar age distributions, irrespective of mineral composition, land use, and soil depth. The results suggest uniform modes of interactions between OC and minerals across soils in quasi-steady state with inputs.
Carlos A. Sierra, Susan E. Crow, Martin Heimann, Holger Metzler, and Ernst-Detlef Schulze
Biogeosciences, 18, 1029–1048, https://doi.org/10.5194/bg-18-1029-2021, https://doi.org/10.5194/bg-18-1029-2021, 2021
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The climate benefit of carbon sequestration (CBS) is a metric developed to quantify avoided warming by two separate processes: the amount of carbon drawdown from the atmosphere and the time this carbon is stored in a reservoir. This metric can be useful for quantifying the role of forests and soils for climate change mitigation and to better quantify the benefits of carbon removals by sinks.
Simon Baumgartner, Matti Barthel, Travis William Drake, Marijn Bauters, Isaac Ahanamungu Makelele, John Kalume Mugula, Laura Summerauer, Nora Gallarotti, Landry Cizungu Ntaboba, Kristof Van Oost, Pascal Boeckx, Sebastian Doetterl, Roland Anton Werner, and Johan Six
Biogeosciences, 17, 6207–6218, https://doi.org/10.5194/bg-17-6207-2020, https://doi.org/10.5194/bg-17-6207-2020, 2020
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Soil respiration is an important carbon flux and key process determining the net ecosystem production of terrestrial ecosystems. The Congo Basin lacks studies quantifying carbon fluxes. We measured soil CO2 fluxes from different forest types in the Congo Basin and were able to show that, even though soil CO2 fluxes are similarly high in lowland and montane forests, the drivers were different: soil moisture in montane forests and C availability in the lowland forests.
Laurent K. Kidinda, Folasade K. Olagoke, Cordula Vogel, Karsten Kalbitz, and Sebastian Doetterl
SOIL Discuss., https://doi.org/10.5194/soil-2020-80, https://doi.org/10.5194/soil-2020-80, 2020
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In deeply weathered tropical rainforest soils of Africa, we found that patterns of microbial processes differ between soils developed from geochemically contrasting parent materials due to differences in resource availability. Across investigated geochemical regions and soil depths, soil microbes were P-limited rather than N-limited. Topsoil microbes were more C-limited than their subsoil counterparts but inversely P-limited.
Christina Schädel, Jeffrey Beem-Miller, Mina Aziz Rad, Susan E. Crow, Caitlin E. Hicks Pries, Jessica Ernakovich, Alison M. Hoyt, Alain Plante, Shane Stoner, Claire C. Treat, and Carlos A. Sierra
Earth Syst. Sci. Data, 12, 1511–1524, https://doi.org/10.5194/essd-12-1511-2020, https://doi.org/10.5194/essd-12-1511-2020, 2020
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Carbon loss to the atmosphere via microbial decomposition is often assessed by laboratory soil incubation studies that measure greenhouse gases released from soils under controlled conditions. Here, we introduce the Soil Incubation Database (SIDb) version 1.0, a compilation of time series data from incubations, structured into a new, publicly available, open-access database of carbon dioxide and methane flux. We also provide guidance for database entry and the required variables.
Ann-Sophie Lehnert, Thomas Behrendt, Alexander Ruecker, Georg Pohnert, and Susan E. Trumbore
Atmos. Meas. Tech., 13, 3507–3520, https://doi.org/10.5194/amt-13-3507-2020, https://doi.org/10.5194/amt-13-3507-2020, 2020
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Volatile organic compounds (VOCs) like scents can appear and disappear quickly. For example, when a bug starts on a tree, the tree releases VOCs that warn the trees around him. Thus, one needs instruments measuring their concentration in real time and identify which VOC is measured. In our study, we compared two instruments doing that, PTR-MS and SIFT-MS. Both work similarly, but we found that the PTR-MS can measure lower concentrations, but the SIFT-MS can identify VOCs better.
Lin Yu, Bernhard Ahrens, Thomas Wutzler, Marion Schrumpf, and Sönke Zaehle
Geosci. Model Dev., 13, 783–803, https://doi.org/10.5194/gmd-13-783-2020, https://doi.org/10.5194/gmd-13-783-2020, 2020
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In this paper, we have developed a new soil organic carbon model that describes the formation and turnover of soil organic matter in a more mechanistic manner. With this model, we are able to better represent how microorganisms and nutrient processes influence the below-ground carbon storage and better explain some observed features of soil organic matter. We hope this model can increase our confidence in predictions of future climate change, particularly on how soil can mitigate the process.
Marco Pfeiffer, José Padarian, Rodrigo Osorio, Nelson Bustamante, Guillermo Federico Olmedo, Mario Guevara, Felipe Aburto, Francisco Albornoz, Monica Antilén, Elías Araya, Eduardo Arellano, Maialen Barret, Juan Barrera, Pascal Boeckx, Margarita Briceño, Sally Bunning, Lea Cabrol, Manuel Casanova, Pablo Cornejo, Fabio Corradini, Gustavo Curaqueo, Sebastian Doetterl, Paola Duran, Mauricio Escudey, Angelina Espinoza, Samuel Francke, Juan Pablo Fuentes, Marcel Fuentes, Gonzalo Gajardo, Rafael García, Audrey Gallaud, Mauricio Galleguillos, Andrés Gomez, Marcela Hidalgo, Jorge Ivelic-Sáez, Lwando Mashalaba, Francisco Matus, Francisco Meza, Maria de la Luz Mora, Jorge Mora, Cristina Muñoz, Pablo Norambuena, Carolina Olivera, Carlos Ovalle, Marcelo Panichini, Aníbal Pauchard, Jorge F. Pérez-Quezada, Sergio Radic, José Ramirez, Nicolás Riveras, Germán Ruiz, Osvaldo Salazar, Iván Salgado, Oscar Seguel, Maria Sepúlveda, Carlos Sierra, Yasna Tapia, Francisco Tapia, Balfredo Toledo, José Miguel Torrico, Susana Valle, Ronald Vargas, Michael Wolff, and Erick Zagal
Earth Syst. Sci. Data, 12, 457–468, https://doi.org/10.5194/essd-12-457-2020, https://doi.org/10.5194/essd-12-457-2020, 2020
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The CHLSOC database is the biggest soil organic carbon (SOC) database that has been compiled for Chile yet, comprising 13 612 data points. This database is the product of the compilation of numerous sources including unpublished and difficult-to-access data, allowing us to fill numerous spatial gaps where no SOC estimates were publicly available before. The values of SOC compiled in CHLSOC have a wide range, reflecting the variety of ecosystems that exists in Chile.
Nora Linscheid, Lina M. Estupinan-Suarez, Alexander Brenning, Nuno Carvalhais, Felix Cremer, Fabian Gans, Anja Rammig, Markus Reichstein, Carlos A. Sierra, and Miguel D. Mahecha
Biogeosciences, 17, 945–962, https://doi.org/10.5194/bg-17-945-2020, https://doi.org/10.5194/bg-17-945-2020, 2020
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Vegetation typically responds to variation in temperature and rainfall within days. Yet seasonal changes in meteorological conditions, as well as decadal climate variability, additionally shape the state of ecosystems. It remains unclear how vegetation responds to climate variability on these different timescales. We find that the vegetation response to climate variability depends on the timescale considered. This scale dependency should be considered for modeling land–atmosphere interactions.
Corey R. Lawrence, Jeffrey Beem-Miller, Alison M. Hoyt, Grey Monroe, Carlos A. Sierra, Shane Stoner, Katherine Heckman, Joseph C. Blankinship, Susan E. Crow, Gavin McNicol, Susan Trumbore, Paul A. Levine, Olga Vindušková, Katherine Todd-Brown, Craig Rasmussen, Caitlin E. Hicks Pries, Christina Schädel, Karis McFarlane, Sebastian Doetterl, Christine Hatté, Yujie He, Claire Treat, Jennifer W. Harden, Margaret S. Torn, Cristian Estop-Aragonés, Asmeret Asefaw Berhe, Marco Keiluweit, Ágatha Della Rosa Kuhnen, Erika Marin-Spiotta, Alain F. Plante, Aaron Thompson, Zheng Shi, Joshua P. Schimel, Lydia J. S. Vaughn, Sophie F. von Fromm, and Rota Wagai
Earth Syst. Sci. Data, 12, 61–76, https://doi.org/10.5194/essd-12-61-2020, https://doi.org/10.5194/essd-12-61-2020, 2020
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The International Soil Radiocarbon Database (ISRaD) is an an open-source archive of soil data focused on datasets including radiocarbon measurements. ISRaD includes data from bulk or
whole soils, distinct soil carbon pools isolated in the laboratory by a variety of soil fractionation methods, samples of soil gas or water collected interstitially from within an intact soil profile, CO2 gas isolated from laboratory soil incubations, and fluxes collected in situ from a soil surface.
Jeroen H. T. Zethof, Martin Leue, Cordula Vogel, Shane W. Stoner, and Karsten Kalbitz
SOIL, 5, 383–398, https://doi.org/10.5194/soil-5-383-2019, https://doi.org/10.5194/soil-5-383-2019, 2019
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A widely overlooked source of carbon (C) in the soil environment is organic C of geogenic origin, e.g. graphite. Appropriate methods are not available to quantify graphite and to differentiate it from other organic and inorganic C sources in soils. Therefore, we examined Fourier transform infrared spectroscopy, thermogravimetric analysis and the smart combustion method for their ability to identify and quantify graphitic C in soils. The smart combustion method showed the most promising results.
Richard K. F. Nair, Kendalynn A. Morris, Martin Hertel, Yunpeng Luo, Gerardo Moreno, Markus Reichstein, Marion Schrumpf, and Mirco Migliavacca
Biogeosciences, 16, 1883–1901, https://doi.org/10.5194/bg-16-1883-2019, https://doi.org/10.5194/bg-16-1883-2019, 2019
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We investigated how nutrient availability affects seasonal timing of root growth and death in a Spanish savanna, adapted to a long summer drought. We found that nitrogen (N) additions led to more root biomass but number of roots was higher with N and phosphorus together. These effects were strongly affected by the time of year. In autumn root growth occurred after leaf production. This has implications for how we understand biomass production and carbon uptake in these systems.
Shaun R. Levick, Anna E. Richards, Garry D. Cook, Jon Schatz, Marcus Guderle, Richard J. Williams, Parash Subedi, Susan E. Trumbore, and Alan N. Andersen
Biogeosciences, 16, 1493–1503, https://doi.org/10.5194/bg-16-1493-2019, https://doi.org/10.5194/bg-16-1493-2019, 2019
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We used airborne lidar to map the three-dimensional structure and model the biomass of plant canopies across a long-term fire experiment in the Northern Territory of Australia. Our results show that late season fires occurring every 2 years reduce the amount of carbon stored above-ground by 50 % relative to unburnt control plots. We also show how increased fire intensity removes the shrub layer from savannas and discuss the implications for biodiversity conservation.
Thomas Behrendt, Elisa C. P. Catão, Rüdiger Bunk, Zhigang Yi, Elena Schweer, Steffen Kolb, Jürgen Kesselmeier, and Susan Trumbore
SOIL, 5, 121–135, https://doi.org/10.5194/soil-5-121-2019, https://doi.org/10.5194/soil-5-121-2019, 2019
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We measured net fluxes of OCS from nine soils with different land use in a dynamic chamber system and analyzed for one soil RNA relative abundance and gene transcripts. Our data suggest that indeed carbonic anhydrase (CA) plays an important role for OCS exchange, but the role of other enzymes might have been underestimated. Our study is the first assessment of the environmental significance of different microbial groups producing and consuming OCS by various enzymes other than CA.
Boaz Hilman, Jan Muhr, Susan E. Trumbore, Norbert Kunert, Mariah S. Carbone, Päivi Yuval, S. Joseph Wright, Gerardo Moreno, Oscar Pérez-Priego, Mirco Migliavacca, Arnaud Carrara, José M. Grünzweig, Yagil Osem, Tal Weiner, and Alon Angert
Biogeosciences, 16, 177–191, https://doi.org/10.5194/bg-16-177-2019, https://doi.org/10.5194/bg-16-177-2019, 2019
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Combined measurement of CO2 / O2 fluxes in tree stems suggested that on average 41 % of the respired CO2 was not emitted locally to the atmosphere. This finding strengthens the recognition that CO2 efflux from tree stems is not an accurate measure of respiration. The CO2 / O2 fluxes did not vary as expected if CO2 dissolution in the xylem sap was the main driver for the CO2 retention. We suggest the examination of refixation of respired CO2 as a possible mechanism for CO2 retention.
Liviu Giosan, William D. Orsi, Marco Coolen, Cornelia Wuchter, Ann G. Dunlea, Kaustubh Thirumalai, Samuel E. Munoz, Peter D. Clift, Jeffrey P. Donnelly, Valier Galy, and Dorian Q. Fuller
Clim. Past, 14, 1669–1686, https://doi.org/10.5194/cp-14-1669-2018, https://doi.org/10.5194/cp-14-1669-2018, 2018
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Climate reorganization during the early neoglacial anomaly (ENA) may explain the Harappan civilization metamorphosis from an urban, expansive culture to a rural, geographically-confined one. Landcover change is a candidate for causing this climate instability. During ENA agriculture along the flood-deficient floodplains of the Indus became too risky, which pushed people out. In the same time the Himalayan piedmont received augmented winter rain and steady summer precipitation, pulling people in.
Verónika Ceballos-Núñez, Andrew D. Richardson, and Carlos A. Sierra
Biogeosciences, 15, 1607–1625, https://doi.org/10.5194/bg-15-1607-2018, https://doi.org/10.5194/bg-15-1607-2018, 2018
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Will the terrestrial biosphere be a carbon source or sink in the future? Different model simulations cannot reach a consensus, so we need to diagnose the performance of these models. We implemented three models differing in their carbon allocation strategies and assessed their performance using three metrics. The most sensible metric was the distribution of carbon age and transit times. Thus, empirical measurements of these distributions could be key to reduce the model uncertainty.
Marta Camino-Serrano, Bertrand Guenet, Sebastiaan Luyssaert, Philippe Ciais, Vladislav Bastrikov, Bruno De Vos, Bert Gielen, Gerd Gleixner, Albert Jornet-Puig, Klaus Kaiser, Dolly Kothawala, Ronny Lauerwald, Josep Peñuelas, Marion Schrumpf, Sara Vicca, Nicolas Vuichard, David Walmsley, and Ivan A. Janssens
Geosci. Model Dev., 11, 937–957, https://doi.org/10.5194/gmd-11-937-2018, https://doi.org/10.5194/gmd-11-937-2018, 2018
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Global models generally oversimplify the representation of soil organic carbon (SOC), and thus its response to global warming remains uncertain. We present the new soil module ORCHIDEE-SOM, within the global model ORCHIDEE, that refines the representation of SOC dynamics and includes the dissolved organic carbon (DOC) processes. The model is able to reproduce SOC stocks and DOC concentrations in four different ecosystems, opening an opportunity for improved predictions of SOC in global models.
Bernd Kohlhepp, Robert Lehmann, Paul Seeber, Kirsten Küsel, Susan E. Trumbore, and Kai U. Totsche
Hydrol. Earth Syst. Sci., 21, 6091–6116, https://doi.org/10.5194/hess-21-6091-2017, https://doi.org/10.5194/hess-21-6091-2017, 2017
Liviu Giosan, Camilo Ponton, Muhammed Usman, Jerzy Blusztajn, Dorian Q. Fuller, Valier Galy, Negar Haghipour, Joel E. Johnson, Cameron McIntyre, Lukas Wacker, and Timothy I. Eglinton
Earth Surf. Dynam., 5, 781–789, https://doi.org/10.5194/esurf-5-781-2017, https://doi.org/10.5194/esurf-5-781-2017, 2017
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A reconstruction of erosion in the core monsoon zone of India provides unintuitive but fundamental insights: in contrast to semiarid regions that experience enhanced erosion during erratic rain events, the monsoon is annual and acts as a veritable
erosional pumpaccelerating when the land cover is minimal. The existence of such a monsoon erosional pump promises to reconcile conflicting views on the land–sea sediment and carbon transfer as well as the monsoon evolution on longer timescales.
Jordon D. Hemingway, Daniel H. Rothman, Sarah Z. Rosengard, and Valier V. Galy
Biogeosciences, 14, 5099–5114, https://doi.org/10.5194/bg-14-5099-2017, https://doi.org/10.5194/bg-14-5099-2017, 2017
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The balance between organic matter (OM) fixation and decay is a major control on atmospheric CO2 concentrations. Understanding the environmental, chemical, and physical mechanisms that control the distribution of OM decay rates is therefore critical for constraining the global carbon cycle. In this manuscript, we derive a method to relate OM reactivity to its isotope composition using a kinetic model and provide a novel framework to discern the controls on OM decay rates.
Martin E. Nowak, Valérie F. Schwab, Cassandre S. Lazar, Thomas Behrendt, Bernd Kohlhepp, Kai Uwe Totsche, Kirsten Küsel, and Susan E. Trumbore
Hydrol. Earth Syst. Sci., 21, 4283–4300, https://doi.org/10.5194/hess-21-4283-2017, https://doi.org/10.5194/hess-21-4283-2017, 2017
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In the present study we combined measurements of dissolved inorganic carbon (DIC) isotopes with a set of different geochemical and microbiological methods in order to get a comprehensive view of biogeochemical cycling and groundwater flow in two limestone aquifer assemblages. This allowed us to understand interactions and feedbacks between microbial communities, their carbon sources, and water chemistry.
Valérie F. Schwab, Martina Herrmann, Vanessa-Nina Roth, Gerd Gleixner, Robert Lehmann, Georg Pohnert, Susan Trumbore, Kirsten Küsel, and Kai U. Totsche
Biogeosciences, 14, 2697–2714, https://doi.org/10.5194/bg-14-2697-2017, https://doi.org/10.5194/bg-14-2697-2017, 2017
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We used phospholipid fatty acids (PLFAs) to link specific microbial markers to the spatio-temporal changes of groundwater physico-chemistry. PLFA-based functional groups were directly supported by DNA/RNA results. O2 resulted in increased eukaryotic biomass and abundance of nitrite-oxidizing bacteria but impeded anammox, sulphate-reducing and iron-reducing bacteria. Our study demonstrates the power of PLFA-based approaches to study the nature and activity of microorganisms in pristine aquifers.
Stephanie K. Jones, Carole Helfter, Margaret Anderson, Mhairi Coyle, Claire Campbell, Daniela Famulari, Chiara Di Marco, Netty van Dijk, Y. Sim Tang, Cairistiona F. E. Topp, Ralf Kiese, Reimo Kindler, Jan Siemens, Marion Schrumpf, Klaus Kaiser, Eiko Nemitz, Peter E. Levy, Robert M. Rees, Mark A. Sutton, and Ute M. Skiba
Biogeosciences, 14, 2069–2088, https://doi.org/10.5194/bg-14-2069-2017, https://doi.org/10.5194/bg-14-2069-2017, 2017
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We assessed the nitrogen (N), carbon (C) and greenhouse gas (GHG) budget from an intensively managed grassland in southern Scotland using flux budget calculations as well as changes in soil N and C pools over time. Estimates from flux budget calculations indicated that N and C were sequestered, whereas soil stock measurements indicated a smaller N storage and a loss of C from the ecosystem. The GHG sink strength of the net CO2 ecosystem exchange was strongly affected by CH4 and N2O emissions.
Carlos A. Sierra, Saadatullah Malghani, and Henry W. Loescher
Biogeosciences, 14, 703–710, https://doi.org/10.5194/bg-14-703-2017, https://doi.org/10.5194/bg-14-703-2017, 2017
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Temperature, moisture, and oxygen are interacting variables that control the rates of soil organic matter decomposition. With a well-replicated experiment, the authors show that decomposition rates in a boreal forest soil are not limited at high temperatures in the presence of enough water and oxygen. Similarly, at high humidity, oxygen is the main limiting factor for decomposition. The authors conclude that interactions among the three variables are the main determinants of decomposition rates.
Lesego Khomo, Susan Trumbore, Carleton R. Bern, and Oliver A. Chadwick
SOIL, 3, 17–30, https://doi.org/10.5194/soil-3-17-2017, https://doi.org/10.5194/soil-3-17-2017, 2017
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We evaluated mineral control of organic carbon dynamics by relating the content and age of carbon stored in soils of varied mineralogical composition found in the landscapes of Kruger National Park, South Africa. Carbon associated with smectite clay minerals, which have stronger surface–organic matter interactions, averaged about a thousand years old, while most soil carbon was only decades to centuries old and was associated with iron and aluminum oxide minerals.
Daniel Magnabosco Marra, Niro Higuchi, Susan E. Trumbore, Gabriel H. P. M. Ribeiro, Joaquim dos Santos, Vilany M. C. Carneiro, Adriano J. N. Lima, Jeffrey Q. Chambers, Robinson I. Negrón-Juárez, Frederic Holzwarth, Björn Reu, and Christian Wirth
Biogeosciences, 13, 1553–1570, https://doi.org/10.5194/bg-13-1553-2016, https://doi.org/10.5194/bg-13-1553-2016, 2016
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Predicting biomass correctly at the landscape level in hyperdiverse and structurally complex tropical forests requires the inclusion of predictors that express inherent variations in species architecture. The model of interest should comprise the floristic composition and size-distribution variability of the target forest, implying that even generic global or pantropical biomass estimation models can lead to strong biases.
Leandro T. dos Santos, Daniel Magnabosco Marra, Susan Trumbore, Plínio B. de Camargo, Robinson I. Negrón-Juárez, Adriano J. N. Lima, Gabriel H. P. M. Ribeiro, Joaquim dos Santos, and Niro Higuchi
Biogeosciences, 13, 1299–1308, https://doi.org/10.5194/bg-13-1299-2016, https://doi.org/10.5194/bg-13-1299-2016, 2016
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In the Amazon forest, wind disturbances can create canopy gaps of many hundreds of hectares. We show that inputs of plant litter associated with large windthrows cause a short-term increase in soil carbon stock. The degree of increase is related to soil clay content and tree mortality intensity. The higher carbon content and potentially higher nutrient availability in soils from areas recovering from windthrows may favor forest regrowth and increase vegetation resilience.
M. E. Nowak, F. Beulig, J. von Fischer, J. Muhr, K. Küsel, and S. E. Trumbore
Biogeosciences, 12, 7169–7183, https://doi.org/10.5194/bg-12-7169-2015, https://doi.org/10.5194/bg-12-7169-2015, 2015
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Microorganisms have been recognized as an important source of soil organic matter (SOM). Autotrophic microorganisms utilize CO2 instead of organic carbon. Microbial CO2 fixation is accompanied with high 13C isotope discrimination. Because autotrophs are abundant in soils, they might be a significant factor influencing 13C signatures of SOM. Thus, it is important to asses the importance of autotrophs for C isotope signatures in soils, in order to use isotopes as a tracer for soil C dynamics.
O. Perez-Priego, J. Guan, M. Rossini, F. Fava, T. Wutzler, G. Moreno, N. Carvalhais, A. Carrara, O. Kolle, T. Julitta, M. Schrumpf, M. Reichstein, and M. Migliavacca
Biogeosciences, 12, 6351–6367, https://doi.org/10.5194/bg-12-6351-2015, https://doi.org/10.5194/bg-12-6351-2015, 2015
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Sun-induced chlorophyll fluorescence and photochemical reflectance index revealed controls of climate and nutrient availability on photosynthesis (gross primary production, GPP). Meteo-driven models (MMs) were unable to describe nutrient-induced effects on GPP. Important implications can be derived from these results, and uncertainties in the prediction of global GPP still remain when MMs do not account for plant nutrient availability.
B. M. Voss, B. Peucker-Ehrenbrink, T. I. Eglinton, R. G. M. Spencer, E. Bulygina, V. Galy, C. H. Lamborg, P. M. Ganguli, D. B. Montluçon, S. Marsh, S. L. Gillies, J. Fanslau, A. Epp, and R. Luymes
Biogeosciences, 12, 5597–5618, https://doi.org/10.5194/bg-12-5597-2015, https://doi.org/10.5194/bg-12-5597-2015, 2015
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This study presents seasonal cycles of organic matter concentration and composition in the Fraser River. Dissolved organic matter patterns are linked to flushing of shallow soil layers during spring snowmelt and fall rain events. The preliminary Hg data set indicates significant changes in concentrations during the spring freshet. Organic carbon export, as both area-normalized yield and the proportion of basin primary productivity, in the Fraser River is typical of large rivers globally.
M. O. Andreae, O. C. Acevedo, A. Araùjo, P. Artaxo, C. G. G. Barbosa, H. M. J. Barbosa, J. Brito, S. Carbone, X. Chi, B. B. L. Cintra, N. F. da Silva, N. L. Dias, C. Q. Dias-Júnior, F. Ditas, R. Ditz, A. F. L. Godoi, R. H. M. Godoi, M. Heimann, T. Hoffmann, J. Kesselmeier, T. Könemann, M. L. Krüger, J. V. Lavric, A. O. Manzi, A. P. Lopes, D. L. Martins, E. F. Mikhailov, D. Moran-Zuloaga, B. W. Nelson, A. C. Nölscher, D. Santos Nogueira, M. T. F. Piedade, C. Pöhlker, U. Pöschl, C. A. Quesada, L. V. Rizzo, C.-U. Ro, N. Ruckteschler, L. D. A. Sá, M. de Oliveira Sá, C. B. Sales, R. M. N. dos Santos, J. Saturno, J. Schöngart, M. Sörgel, C. M. de Souza, R. A. F. de Souza, H. Su, N. Targhetta, J. Tóta, I. Trebs, S. Trumbore, A. van Eijck, D. Walter, Z. Wang, B. Weber, J. Williams, J. Winderlich, F. Wittmann, S. Wolff, and A. M. Yáñez-Serrano
Atmos. Chem. Phys., 15, 10723–10776, https://doi.org/10.5194/acp-15-10723-2015, https://doi.org/10.5194/acp-15-10723-2015, 2015
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This paper describes the Amazon Tall Tower Observatory (ATTO), a new atmosphere-biosphere observatory located in the remote Amazon Basin. It presents results from ecosystem ecology, meteorology, trace gas, and aerosol measurements collected at the ATTO site during the first 3 years of operation.
M. S. Torn, A. Chabbi, P. Crill, P. J. Hanson, I. A. Janssens, Y. Luo, C. H. Pries, C. Rumpel, M. W. I. Schmidt, J. Six, M. Schrumpf, and B. Zhu
SOIL, 1, 575–582, https://doi.org/10.5194/soil-1-575-2015, https://doi.org/10.5194/soil-1-575-2015, 2015
S. Doetterl, J.-T. Cornelis, J. Six, S. Bodé, S. Opfergelt, P. Boeckx, and K. Van Oost
Biogeosciences, 12, 1357–1371, https://doi.org/10.5194/bg-12-1357-2015, https://doi.org/10.5194/bg-12-1357-2015, 2015
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We link the mineralogy of soils affected by erosion and deposition to the distribution of soil carbon fractions, their turnover and microbial activity. We show that the weathering status of soils and their history are controlling the stabilization of carbon with minerals. After burial, aggregated C is preserved more efficiently while non-aggregated C can be released and younger C re-sequestered more easily. Weathering changes the effectiveness of stabilization mechanism limiting this C sink.
C. A. Sierra, M. Müller, and S. E. Trumbore
Geosci. Model Dev., 7, 1919–1931, https://doi.org/10.5194/gmd-7-1919-2014, https://doi.org/10.5194/gmd-7-1919-2014, 2014
B. Ahrens, M. Reichstein, W. Borken, J. Muhr, S. E. Trumbore, and T. Wutzler
Biogeosciences, 11, 2147–2168, https://doi.org/10.5194/bg-11-2147-2014, https://doi.org/10.5194/bg-11-2147-2014, 2014
M. S. Torn, M. Kleber, E. S. Zavaleta, B. Zhu, C. B. Field, and S. E. Trumbore
Biogeosciences, 10, 8067–8081, https://doi.org/10.5194/bg-10-8067-2013, https://doi.org/10.5194/bg-10-8067-2013, 2013
S. R. Shah, D. R. Griffith, V. Galy, A. P. McNichol, and T. I. Eglinton
Biogeosciences, 10, 7065–7080, https://doi.org/10.5194/bg-10-7065-2013, https://doi.org/10.5194/bg-10-7065-2013, 2013
E. Solly, I. Schöning, S. Boch, J. Müller, S. A. Socher, S. E. Trumbore, and M. Schrumpf
Biogeosciences, 10, 4833–4843, https://doi.org/10.5194/bg-10-4833-2013, https://doi.org/10.5194/bg-10-4833-2013, 2013
C. A. Sierra, E. M. Jiménez, B. Reu, M. C. Peñuela, A. Thuille, and C. A. Quesada
Biogeosciences, 10, 3455–3464, https://doi.org/10.5194/bg-10-3455-2013, https://doi.org/10.5194/bg-10-3455-2013, 2013
M. Schrumpf, K. Kaiser, G. Guggenberger, T. Persson, I. Kögel-Knabner, and E.-D. Schulze
Biogeosciences, 10, 1675–1691, https://doi.org/10.5194/bg-10-1675-2013, https://doi.org/10.5194/bg-10-1675-2013, 2013
M. C. Braakhekke, T. Wutzler, C. Beer, J. Kattge, M. Schrumpf, B. Ahrens, I. Schöning, M. R. Hoosbeek, B. Kruijt, P. Kabat, and M. Reichstein
Biogeosciences, 10, 399–420, https://doi.org/10.5194/bg-10-399-2013, https://doi.org/10.5194/bg-10-399-2013, 2013
Related subject area
Biogeochemistry: Soils
Diverse organic carbon dynamics captured by radiocarbon analysis of distinct compound classes in a grassland soil
The effects of land use on soil carbon stocks in the UK
Technical note: A validated correction method to quantify organic and inorganic carbon in soils using Rock-Eval® thermal analysis
Vegetation patterns associated with nutrient availability and supply in high-elevation tropical Andean ecosystems
A new approach to continuous monitoring of carbon use efficiency and biosynthesis in soil microbes from measurement of CO2 and O2
Technical note: An open-source, low-cost system for continuous monitoring of low nitrate concentrations in soil and open water
Plutonium concentrations link soil organic matter decline to wind erosion in ploughed soils of South Africa
A Synthesis of Sphagnum Litterbag Experiments: Initial Leaching Losses Bias Decomposition Rate Estimates
Long-term fertilization increases soil but not plant or microbial N in a Chihuahuan Desert grassland
Factors controlling spatiotemporal variability of soil carbon accumulation and stock estimates in a tidal salt marsh
Effect of straw retention and mineral fertilization on P speciation and P-transformation microorganisms in water extractable colloids of a Vertisol
Moisture and temperature effects on the radiocarbon signature of respired carbon dioxide to assess stability of soil carbon in the Tibetan Plateau
Non-mycorrhizal root-associated fungi increase soil C stocks and stability via diverse mechanisms
Nine years of warming and nitrogen addition in the Tibetan grassland promoted loss of soil organic carbon but did not alter the bulk change in chemical structure
Soil priming effects and involved microbial community along salt gradients
Adjustments to the Rock-Eval® thermal analysis for soil organic and inorganic carbon quantification
Ecosystem-specific patterns and drivers of global reactive iron mineral-associated organic carbon
Dark septate endophytic fungi associated with pioneer grass inhabiting volcanic deposits and their functions in promoting plant growth
Global patterns and drivers of phosphorus fractions in natural soils
Reviews and syntheses: Iron – a driver of nitrogen bioavailability in soils?
Differential temperature sensitivity of intracellular metabolic processes and extracellular soil enzyme activities
Mapping soil organic carbon fractions for Australia, their stocks, and uncertainty
Technical note: The recovery rate of free particulate organic matter from soil samples is strongly affected by the method of density fractionation
Deforestation for agriculture leads to soil warming and enhanced litter decomposition in subarctic soils
Temperature sensitivity of soil organic carbon respiration along a forested elevation gradient in the Rwenzori Mountains, Uganda
The influence of elevated CO2 and soil depth on rhizosphere activity and nutrient availability in a mature Eucalyptus woodland
The paradox of assessing greenhouse gases from soils for nature-based solutions
Management-induced changes in soil organic carbon on global croplands
Pore network modeling as a new tool for determining gas diffusivity in peat
Temperature sensitivity of dark CO2 fixation in temperate forest soils
Effects of precipitation seasonality, irrigation, vegetation cycle and soil type on enhanced weathering – modeling of cropland case studies across four sites
Stable isotope profiles of soil organic carbon in forested and grassland landscapes in the Lake Alaotra basin (Madagascar): insights in past vegetation changes
Reviews and syntheses: The promise of big diverse soil data, moving current practices towards future potential
Dynamics of rare earth elements and associated major and trace elements during Douglas-fir (Pseudotsuga menziesii) and European beech (Fagus sylvatica L.) litter degradation
To what extent can soil moisture and soil Cu contamination stresses affect nitrous species emissions? Estimation through calibration of a nitrification–denitrification model
Carbon, nitrogen, and phosphorus stoichiometry of organic matter in Swedish forest soils and its relationship with climate, tree species, and soil texture
Soil geochemistry as a driver of soil organic matter composition: insights from a soil chronosequence
Leaching of inorganic and organic phosphorus and nitrogen in contrasting beech forest soils – seasonal patterns and effects of fertilization
Age and chemistry of dissolved organic carbon reveal enhanced leaching of ancient labile carbon at the permafrost thaw zone
Soil organic carbon stabilization mechanisms and temperature sensitivity in old terraced soils
Effect of organic carbon addition on paddy soil organic carbon decomposition under different irrigation regimes
Soil profile connectivity can impact microbial substrate use, affecting how soil CO2 effluxes are controlled by temperature
Additional carbon inputs to reach a 4 per 1000 objective in Europe: feasibility and projected impacts of climate change based on Century simulations of long-term arable experiments
Cycling and retention of nitrogen in European beech (Fagus sylvatica L.) ecosystems under elevated fructification frequency
Mercury mobility, colloid formation and methylation in a polluted Fluvisol as affected by manure application and flooding–draining cycle
Simulating measurable ecosystem carbon and nitrogen dynamics with the mechanistically defined MEMS 2.0 model
Similar importance of edaphic and climatic factors for controlling soil organic carbon stocks of the world
Representing methane emissions from wet tropical forest soils using microbial functional groups constrained by soil diffusivity
Long-term bare-fallow soil fractions reveal thermo-chemical properties controlling soil organic carbon dynamics
Geochemical zones and environmental gradients for soils from the central Transantarctic Mountains, Antarctica
Katherine E. Grant, Marisa N. Repasch, Kari M. Finstad, Julia D. Kerr, Maxwell Marple, Christopher J. Larson, Taylor A. B. Broek, Jennifer Pett-Ridge, and Karis J. McFarlane
Biogeosciences, 21, 4395–4411, https://doi.org/10.5194/bg-21-4395-2024, https://doi.org/10.5194/bg-21-4395-2024, 2024
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Soils store organic carbon composed of multiple compounds from plants and microbes for different lengths of time. To understand how soils store these different carbon types, we measure the time each carbon fraction is in a grassland soil profile. Our results show that the length of time each individual soil fraction is in our soil changes. Our approach allows a detailed look at the different components in soils. This study can help improve our understanding of soil dynamics.
Peter Levy, Laura Bentley, Peter Danks, Bridget Emmett, Angus Garbutt, Stephen Heming, Peter Henrys, Aidan Keith, Inma Lebron, Niall McNamara, Richard Pywell, John Redhead, David Robinson, and Alexander Wickenden
Biogeosciences, 21, 4301–4315, https://doi.org/10.5194/bg-21-4301-2024, https://doi.org/10.5194/bg-21-4301-2024, 2024
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We collated a large data set (15 790 soil cores) on soil carbon stock in different land uses. Soil carbon stocks were highest in woodlands and lowest in croplands. The variability in the effects was large. This has important implications for agri-environment schemes seeking to sequester carbon in the soil by altering land use because the effect of a given intervention is very hard to verify.
Marija Stojanova, Pierre Arbelet, François Baudin, Nicolas Bouton, Giovanni Caria, Lorenza Pacini, Nicolas Proix, Edouard Quibel, Achille Thin, and Pierre Barré
Biogeosciences, 21, 4229–4237, https://doi.org/10.5194/bg-21-4229-2024, https://doi.org/10.5194/bg-21-4229-2024, 2024
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Because of its importance for climate regulation and soil health, many studies focus on carbon dynamics in soils. However, quantifying organic and inorganic carbon remains an issue in carbonated soils. In this technical note, we propose a validated correction method to quantify organic and inorganic carbon in soils using Rock-Eval® thermal analysis. With this correction, the Rock-Eval® method has the potential to become the standard method for quantifying carbon in carbonate soils.
Armando Molina, Veerle Vanacker, Oliver Chadwick, Santiago Zhiminaicela, Marife Corre, and Edzo Veldkamp
Biogeosciences, 21, 3075–3091, https://doi.org/10.5194/bg-21-3075-2024, https://doi.org/10.5194/bg-21-3075-2024, 2024
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The tropical Andes contains unique landscapes where forest patches are surrounded by tussock grasses and cushion-forming plants. The aboveground vegetation composition informs us about belowground nutrient availability: patterns in plant-available nutrients resulted from strong biocycling of cations and removal of soil nutrients by plant uptake or leaching. Future changes in vegetation distribution will affect soil water and solute fluxes and the aquatic ecology of Andean rivers and lakes.
Kyle E. Smart, Daniel O. Breecker, Christopher B. Blackwood, and Timothy M. Gallagher
EGUsphere, https://doi.org/10.5194/egusphere-2024-1757, https://doi.org/10.5194/egusphere-2024-1757, 2024
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When microbes consume carbon within soils, it is important to know how much carbon is respired and lost as carbon dioxide versus how much is used to make new biomass. We used a new approach of monitoring carbon dioxide and oxygen to track the fate of consumed carbon during a series of laboratory experiments where sugar was added to moistened soil. Our approach allowed us to estimate how much sugar was converted to dead microbial biomass, which is more likely to be preserved in soils.
Sahiti Bulusu, Cristina Prieto García, Helen E. Dahlke, and Elad Levintal
Biogeosciences, 21, 3007–3013, https://doi.org/10.5194/bg-21-3007-2024, https://doi.org/10.5194/bg-21-3007-2024, 2024
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Do-it-yourself hardware is a new way to improve measurement resolution. We present a low-cost, automated system for field measurements of low nitrate concentrations in soil porewater and open water bodies. All data hardware components cost USD 1100, which is much cheaper than other available commercial solutions. We provide the complete building guide to reduce technical barriers, which we hope will allow easier reproducibility and set up new soil and environmental monitoring applications.
Joel Mohren, Hendrik Wiesel, Wulf Amelung, L. Keith Fifield, Alexandra Sandhage-Hofmann, Erik Strub, Steven A. Binnie, Stefan Heinze, Elmarie Kotze, Chris Du Preez, Stephen G. Tims, and Tibor J. Dunai
EGUsphere, https://doi.org/10.5194/egusphere-2024-1312, https://doi.org/10.5194/egusphere-2024-1312, 2024
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We measured concentrations of fallout radionuclides (FRNs) in soil samples taken from arable land in South Africa. We find that during the second half of the 20th century CE, the FRN data strongly correlate with the soil organic matter (SOM) content of the soils. The finding implies that wind erosion strongly influenced SOM loss in the soils we investigated. Furthermore, the exponential decline of FRN concentrations and SOM content over time peaks shortly after native grassland is cultivated.
Henning Teickner, Edzer Pebesma, and Klaus-Holger Knorr
EGUsphere, https://doi.org/10.5194/egusphere-2024-1686, https://doi.org/10.5194/egusphere-2024-1686, 2024
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Decomposition rates for Sphagnum mosses, the main peat forming plants in northern peatlands, are often derived from litterbag experiments. Here, we estimate initial leaching losses from available Sphagnum litterbag experiments and analyze how decomposition rates are biased when initial leaching losses are ignored. Our analyses indicate that initial leaching losses range between 3 to 18 mass-% and that this may result in overestimated mass losses when extrapolated to several decades.
Violeta Mendoza-Martinez, Scott L. Collins, and Jennie R. McLaren
Biogeosciences, 21, 2655–2667, https://doi.org/10.5194/bg-21-2655-2024, https://doi.org/10.5194/bg-21-2655-2024, 2024
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We examine the impacts of multi-decadal nitrogen additions on a dryland ecosystem N budget, including the soil, microbial, and plant N pools. After 26 years, there appears to be little impact on the soil microbial or plant community and only minimal increases in N pools within the soil. While perhaps encouraging from a conservation standpoint, we calculate that greater than 95 % of the nitrogen added to the system is not retained and is instead either lost deeper in the soil or emitted as gas.
Sean Fettrow, Andrew Wozniak, Holly A. Michael, and Angelia L. Seyfferth
Biogeosciences, 21, 2367–2384, https://doi.org/10.5194/bg-21-2367-2024, https://doi.org/10.5194/bg-21-2367-2024, 2024
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Salt marshes play a big role in global carbon (C) storage, and C stock estimates are used to predict future changes. However, spatial and temporal gradients in C burial rates over the landscape exist due to variations in water inundation, dominant plant species and stage of growth, and tidal action. We quantified soil C concentrations in soil cores across time and space beside several porewater biogeochemical variables and discussed the controls on variability in soil C in salt marsh ecosystems.
Shanshan Bai, Yifei Ge, Dongtan Yao, Yifan Wang, Jinfang Tan, Shuai Zhang, Yutao Peng, and Xiaoqian Jiang
EGUsphere, https://doi.org/10.5194/egusphere-2024-983, https://doi.org/10.5194/egusphere-2024-983, 2024
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Mineral fertilization led to increases in total P, available P, high-activity inorganic P fractions and organic P, but decreased the abundances of P cycling genes by decreasing soil pH and increasing P in bulk soil. Straw retention brought increases for organic C, total P, available P concentrations in water-extractable colloids (WECs). Abundances of phoD gene and phoD-harbouring Proteobacteria in WECs increased under straw retention, suggesting that the P mineralizing capacity increased.
Andrés Tangarife-Escobar, Georg Guggenberger, Xiaojuan Feng, Guohua Dai, Carolina Urbina-Malo, Mina Azizi-Rad, and Carlos A. Sierra
Biogeosciences, 21, 1277–1299, https://doi.org/10.5194/bg-21-1277-2024, https://doi.org/10.5194/bg-21-1277-2024, 2024
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Soil organic matter stability depends on future temperature and precipitation scenarios. We used radiocarbon (14C) data and model predictions to understand how the transit time of carbon varies under environmental change in grasslands and peatlands. Soil moisture affected the Δ14C of peatlands, while temperature did not have any influence. Our models show the correspondence between Δ14C and transit time and could allow understanding future interactions between terrestrial and atmospheric carbon
Emiko K. Stuart, Laura Castañeda-Gómez, Wolfram Buss, Jeff R. Powell, and Yolima Carrillo
Biogeosciences, 21, 1037–1059, https://doi.org/10.5194/bg-21-1037-2024, https://doi.org/10.5194/bg-21-1037-2024, 2024
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We inoculated wheat plants with various types of fungi whose impacts on soil carbon are poorly understood. After several months of growth, we examined both their impacts on soil carbon and the underlying mechanisms using multiple methods. Overall the fungi benefitted the storage of carbon in soil, mainly by improving the stability of pre-existing carbon, but several pathways were involved. This study demonstrates their importance for soil carbon storage and, therefore, climate change mitigation.
Huimin Sun, Michael W. I. Schmidt, Jintao Li, Jinquan Li, Xiang Liu, Nicholas O. E. Ofiti, Shurong Zhou, and Ming Nie
Biogeosciences, 21, 575–589, https://doi.org/10.5194/bg-21-575-2024, https://doi.org/10.5194/bg-21-575-2024, 2024
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A soil organic carbon (SOC) molecular structure suggested that the easily decomposable and stabilized SOC is similarly affected after 9-year warming and N treatments despite large changes in SOC stocks. Given the long residence time of some SOC, the similar loss of all measurable chemical forms of SOC under global change treatments could have important climate consequences.
Haoli Zhang, Doudou Chang, Zhifeng Zhu, Chunmei Meng, and Kaiyong Wang
Biogeosciences, 21, 1–11, https://doi.org/10.5194/bg-21-1-2024, https://doi.org/10.5194/bg-21-1-2024, 2024
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Soil salinity mediates microorganisms and soil processes like soil organic carbon (SOC) cycling. We observed that negative priming effects at the early stages might be due to the preferential utilization of cottonseed meal. The positive priming that followed decreased with the increase in salinity.
Joséphine Hazera, David Sebag, Isabelle Kowalewski, Eric Verrecchia, Herman Ravelojaona, and Tiphaine Chevallier
Biogeosciences, 20, 5229–5242, https://doi.org/10.5194/bg-20-5229-2023, https://doi.org/10.5194/bg-20-5229-2023, 2023
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This study adapts the Rock-Eval® protocol to quantify soil organic carbon (SOC) and soil inorganic carbon (SIC) on a non-pretreated soil aliquot. The standard protocol properly estimates SOC contents once the TOC parameter is corrected. However, it cannot complete the thermal breakdown of SIC amounts > 4 mg, leading to an underestimation of high SIC contents by the MinC parameter, even after correcting for this. Thus, the final oxidation isotherm is extended to 7 min to quantify any SIC amount.
Bo Zhao, Amin Dou, Zhiwei Zhang, Zhenyu Chen, Wenbo Sun, Yanli Feng, Xiaojuan Wang, and Qiang Wang
Biogeosciences, 20, 4761–4774, https://doi.org/10.5194/bg-20-4761-2023, https://doi.org/10.5194/bg-20-4761-2023, 2023
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This study provided a comprehensive analysis of the spatial variability and determinants of Fe-bound organic carbon (Fe-OC) among terrestrial, wetland, and marine ecosystems and its governing factors globally. We illustrated that reactive Fe was not only an important sequestration mechanism for OC in terrestrial ecosystems but also an effective “rusty sink” of OC preservation in wetland and marine ecosystems, i.e., a key factor for long-term OC storage in global ecosystems.
Han Sun, Tomoyasu Nishizawa, Hiroyuki Ohta, and Kazuhiko Narisawa
Biogeosciences, 20, 4737–4749, https://doi.org/10.5194/bg-20-4737-2023, https://doi.org/10.5194/bg-20-4737-2023, 2023
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In this research, we assessed the diversity and function of the dark septate endophytic (DSE) fungi community associated with Miscanthus condensatus root in volcanic ecosystems. Both metabarcoding and isolation were adopted in this study. We further validated effects on plant growth by inoculation of some core DSE isolates. This study helps improve our understanding of the role of Miscanthus condensatus-associated DSE fungi during the restoration of post-volcanic ecosystems.
Xianjin He, Laurent Augusto, Daniel S. Goll, Bruno Ringeval, Ying-Ping Wang, Julian Helfenstein, Yuanyuan Huang, and Enqing Hou
Biogeosciences, 20, 4147–4163, https://doi.org/10.5194/bg-20-4147-2023, https://doi.org/10.5194/bg-20-4147-2023, 2023
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We identified total soil P concentration as the most important predictor of all soil P pool concentrations, except for primary mineral P concentration, which is primarily controlled by soil pH and only secondarily by total soil P concentration. We predicted soil P pools’ distributions in natural systems, which can inform assessments of the role of natural P availability for ecosystem productivity, climate change mitigation, and the functioning of the Earth system.
Imane Slimani, Xia Zhu-Barker, Patricia Lazicki, and William Horwath
Biogeosciences, 20, 3873–3894, https://doi.org/10.5194/bg-20-3873-2023, https://doi.org/10.5194/bg-20-3873-2023, 2023
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There is a strong link between nitrogen availability and iron minerals in soils. These minerals have multiple outcomes for nitrogen availability depending on soil conditions and properties. For example, iron can limit microbial degradation of nitrogen in aerated soils but has opposing outcomes in non-aerated soils. This paper focuses on the multiple ways iron can affect nitrogen bioavailability in soils.
Adetunji Alex Adekanmbi, Laurence Dale, Liz Shaw, and Tom Sizmur
Biogeosciences, 20, 2207–2219, https://doi.org/10.5194/bg-20-2207-2023, https://doi.org/10.5194/bg-20-2207-2023, 2023
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The decomposition of soil organic matter and flux of carbon dioxide are expected to increase as temperatures rise. However, soil organic matter decomposition is a two-step process whereby large molecules are first broken down outside microbial cells and then respired within microbial cells. We show here that these two steps are not equally sensitive to increases in soil temperature and that global warming may cause a shift in the rate-limiting step from outside to inside the microbial cell.
Mercedes Román Dobarco, Alexandre M. J-C. Wadoux, Brendan Malone, Budiman Minasny, Alex B. McBratney, and Ross Searle
Biogeosciences, 20, 1559–1586, https://doi.org/10.5194/bg-20-1559-2023, https://doi.org/10.5194/bg-20-1559-2023, 2023
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Soil organic carbon (SOC) is of a heterogeneous nature and varies in chemistry, stabilisation mechanisms, and persistence in soil. In this study we mapped the stocks of SOC fractions with different characteristics and turnover rates (presumably PyOC >= MAOC > POC) across Australia, combining spectroscopy and digital soil mapping. The SOC stocks (0–30 cm) were estimated as 13 Pg MAOC, 2 Pg POC, and 5 Pg PyOC.
Frederick Büks
Biogeosciences, 20, 1529–1535, https://doi.org/10.5194/bg-20-1529-2023, https://doi.org/10.5194/bg-20-1529-2023, 2023
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Ultrasonication with density fractionation of soils is a commonly used method to separate soil organic matter pools, which is, e.g., important to calculate carbon turnover in landscapes. It is shown that the approach that merges soil and dense solution without mixing has a low recovery rate and causes co-extraction of parts of the retained labile pool along with the intermediate pool. An alternative method with high recovery rates and no cross-contamination was recommended.
Tino Peplau, Christopher Poeplau, Edward Gregorich, and Julia Schroeder
Biogeosciences, 20, 1063–1074, https://doi.org/10.5194/bg-20-1063-2023, https://doi.org/10.5194/bg-20-1063-2023, 2023
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We buried tea bags and temperature loggers in a paired-plot design in soils under forest and agricultural land and retrieved them after 2 years to quantify the effect of land-use change on soil temperature and litter decomposition in subarctic agricultural systems. We could show that agricultural soils were on average 2 °C warmer than forests and that litter decomposition was enhanced. The results imply that deforestation amplifies effects of climate change on soil organic matter dynamics.
Joseph Okello, Marijn Bauters, Hans Verbeeck, Samuel Bodé, John Kasenene, Astrid Françoys, Till Engelhardt, Klaus Butterbach-Bahl, Ralf Kiese, and Pascal Boeckx
Biogeosciences, 20, 719–735, https://doi.org/10.5194/bg-20-719-2023, https://doi.org/10.5194/bg-20-719-2023, 2023
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The increase in global and regional temperatures has the potential to drive accelerated soil organic carbon losses in tropical forests. We simulated climate warming by translocating intact soil cores from higher to lower elevations. The results revealed increasing temperature sensitivity and decreasing losses of soil organic carbon with increasing elevation. Our results suggest that climate warming may trigger enhanced losses of soil organic carbon from tropical montane forests.
Johanna Pihlblad, Louise C. Andresen, Catriona A. Macdonald, David S. Ellsworth, and Yolima Carrillo
Biogeosciences, 20, 505–521, https://doi.org/10.5194/bg-20-505-2023, https://doi.org/10.5194/bg-20-505-2023, 2023
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Elevated CO2 in the atmosphere increases forest biomass productivity when growth is not limited by soil nutrients. This study explores how mature trees stimulate soil availability of nitrogen and phosphorus with free-air carbon dioxide enrichment after 5 years of fumigation. We found that both nutrient availability and processes feeding available pools increased in the rhizosphere, and phosphorus increased at depth. This appears to not be by decomposition but by faster recycling of nutrients.
Rodrigo Vargas and Van Huong Le
Biogeosciences, 20, 15–26, https://doi.org/10.5194/bg-20-15-2023, https://doi.org/10.5194/bg-20-15-2023, 2023
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Quantifying the role of soils in nature-based solutions requires accurate estimates of soil greenhouse gas (GHG) fluxes. We suggest that multiple GHG fluxes should not be simultaneously measured at a few fixed time intervals, but an optimized sampling approach can reduce bias and uncertainty. Our results have implications for assessing GHG fluxes from soils and a better understanding of the role of soils in nature-based solutions.
Kristine Karstens, Benjamin Leon Bodirsky, Jan Philipp Dietrich, Marta Dondini, Jens Heinke, Matthias Kuhnert, Christoph Müller, Susanne Rolinski, Pete Smith, Isabelle Weindl, Hermann Lotze-Campen, and Alexander Popp
Biogeosciences, 19, 5125–5149, https://doi.org/10.5194/bg-19-5125-2022, https://doi.org/10.5194/bg-19-5125-2022, 2022
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Soil organic carbon (SOC) has been depleted by anthropogenic land cover change and agricultural management. While SOC models often simulate detailed biochemical processes, the management decisions are still little investigated at the global scale. We estimate that soils have lost around 26 GtC relative to a counterfactual natural state in 1975. Yet, since 1975, SOC has been increasing again by 4 GtC due to a higher productivity, recycling of crop residues and manure, and no-tillage practices.
Petri Kiuru, Marjo Palviainen, Arianna Marchionne, Tiia Grönholm, Maarit Raivonen, Lukas Kohl, and Annamari Laurén
Biogeosciences, 19, 5041–5058, https://doi.org/10.5194/bg-19-5041-2022, https://doi.org/10.5194/bg-19-5041-2022, 2022
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Peatlands are large carbon stocks. Emissions of carbon dioxide and methane from peatlands may increase due to changes in management and climate. We studied the variation in the gas diffusivity of peat with depth using pore network simulations and laboratory experiments. Gas diffusivity was found to be lower in deeper peat with smaller pores and lower pore connectivity. However, gas diffusivity was not extremely low in wet conditions, which may reflect the distinctive structure of peat.
Rachael Akinyede, Martin Taubert, Marion Schrumpf, Susan Trumbore, and Kirsten Küsel
Biogeosciences, 19, 4011–4028, https://doi.org/10.5194/bg-19-4011-2022, https://doi.org/10.5194/bg-19-4011-2022, 2022
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Soils will likely become warmer in the future, and this can increase the release of carbon dioxide (CO2) into the atmosphere. As microbes can take up soil CO2 and prevent further escape into the atmosphere, this study compares the rate of uptake and release of CO2 at two different temperatures. With warming, the rate of CO2 uptake increases less than the rate of release, indicating that the capacity to modulate soil CO2 release into the atmosphere will decrease under future warming.
Giuseppe Cipolla, Salvatore Calabrese, Amilcare Porporato, and Leonardo V. Noto
Biogeosciences, 19, 3877–3896, https://doi.org/10.5194/bg-19-3877-2022, https://doi.org/10.5194/bg-19-3877-2022, 2022
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Enhanced weathering (EW) is a promising strategy for carbon sequestration. Since models may help to characterize field EW, the present work applies a hydro-biogeochemical model to four case studies characterized by different rainfall seasonality, vegetation and soil type. Rainfall seasonality strongly affects EW dynamics, but low carbon sequestration suggests that an in-depth analysis at the global scale is required to see if EW may be effective to mitigate climate change.
Vao Fenotiana Razanamahandry, Marjolein Dewaele, Gerard Govers, Liesa Brosens, Benjamin Campforts, Liesbet Jacobs, Tantely Razafimbelo, Tovonarivo Rafolisy, and Steven Bouillon
Biogeosciences, 19, 3825–3841, https://doi.org/10.5194/bg-19-3825-2022, https://doi.org/10.5194/bg-19-3825-2022, 2022
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In order to shed light on possible past vegetation shifts in the Central Highlands of Madagascar, we measured stable isotope ratios of organic carbon in soil profiles along both forested and grassland hillslope transects in the Lake Alaotra region. Our results show that the landscape of this region was more forested in the past: soils in the C4-dominated grasslands contained a substantial fraction of C3-derived carbon, increasing with depth.
Katherine E. O. Todd-Brown, Rose Z. Abramoff, Jeffrey Beem-Miller, Hava K. Blair, Stevan Earl, Kristen J. Frederick, Daniel R. Fuka, Mario Guevara Santamaria, Jennifer W. Harden, Katherine Heckman, Lillian J. Heran, James R. Holmquist, Alison M. Hoyt, David H. Klinges, David S. LeBauer, Avni Malhotra, Shelby C. McClelland, Lucas E. Nave, Katherine S. Rocci, Sean M. Schaeffer, Shane Stoner, Natasja van Gestel, Sophie F. von Fromm, and Marisa L. Younger
Biogeosciences, 19, 3505–3522, https://doi.org/10.5194/bg-19-3505-2022, https://doi.org/10.5194/bg-19-3505-2022, 2022
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Research data are becoming increasingly available online with tantalizing possibilities for reanalysis. However harmonizing data from different sources remains challenging. Using the soils community as an example, we walked through the various strategies that researchers currently use to integrate datasets for reanalysis. We find that manual data transcription is still extremely common and that there is a critical need for community-supported informatics tools like vocabularies and ontologies.
Alessandro Montemagno, Christophe Hissler, Victor Bense, Adriaan J. Teuling, Johanna Ziebel, and Laurent Pfister
Biogeosciences, 19, 3111–3129, https://doi.org/10.5194/bg-19-3111-2022, https://doi.org/10.5194/bg-19-3111-2022, 2022
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We investigated the biogeochemical processes that dominate the release and retention of elements (nutrients and potentially toxic elements) during litter degradation. Our results show that toxic elements are retained in the litter, while nutrients are released in solution during the first stages of degradation. This seems linked to the capability of trees to distribute the elements between degradation-resistant and non-degradation-resistant compounds of leaves according to their chemical nature.
Laura Sereni, Bertrand Guenet, Charlotte Blasi, Olivier Crouzet, Jean-Christophe Lata, and Isabelle Lamy
Biogeosciences, 19, 2953–2968, https://doi.org/10.5194/bg-19-2953-2022, https://doi.org/10.5194/bg-19-2953-2022, 2022
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This study focused on the modellisation of two important drivers of soil greenhouse gas emissions: soil contamination and soil moisture change. The aim was to include a Cu function in the soil biogeochemical model DNDC for different soil moisture conditions and then to estimate variation in N2O, NO2 or NOx emissions. Our results show a larger effect of Cu on N2 and N2O emissions than on the other nitrogen species and a higher effect for the soils incubated under constant constant moisture.
Marie Spohn and Johan Stendahl
Biogeosciences, 19, 2171–2186, https://doi.org/10.5194/bg-19-2171-2022, https://doi.org/10.5194/bg-19-2171-2022, 2022
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We explored the ratios of carbon (C), nitrogen (N), and phosphorus (P) of organic matter in Swedish forest soils. The N : P ratio of the organic layer was most strongly related to the mean annual temperature, while the C : N ratios of the organic layer and mineral soil were strongly related to tree species even in the subsoil. The organic P concentration in the mineral soil was strongly affected by soil texture, which diminished the effect of tree species on the C to organic P (C : OP) ratio.
Moritz Mainka, Laura Summerauer, Daniel Wasner, Gina Garland, Marco Griepentrog, Asmeret Asefaw Berhe, and Sebastian Doetterl
Biogeosciences, 19, 1675–1689, https://doi.org/10.5194/bg-19-1675-2022, https://doi.org/10.5194/bg-19-1675-2022, 2022
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The largest share of terrestrial carbon is stored in soils, making them highly relevant as regards global change. Yet, the mechanisms governing soil carbon stabilization are not well understood. The present study contributes to a better understanding of these processes. We show that qualitative changes in soil organic matter (SOM) co-vary with alterations of the soil matrix following soil weathering. Hence, the type of SOM that is stabilized in soils might change as soils develop.
Jasmin Fetzer, Emmanuel Frossard, Klaus Kaiser, and Frank Hagedorn
Biogeosciences, 19, 1527–1546, https://doi.org/10.5194/bg-19-1527-2022, https://doi.org/10.5194/bg-19-1527-2022, 2022
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As leaching is a major pathway of nitrogen and phosphorus loss in forest soils, we investigated several potential drivers in two contrasting beech forests. The composition of leachates, obtained by zero-tension lysimeters, varied by season, and climatic extremes influenced the magnitude of leaching. Effects of nitrogen and phosphorus fertilization varied with soil nutrient status and sorption properties, and leaching from the low-nutrient soil was more sensitive to environmental factors.
Karis J. McFarlane, Heather M. Throckmorton, Jeffrey M. Heikoop, Brent D. Newman, Alexandra L. Hedgpeth, Marisa N. Repasch, Thomas P. Guilderson, and Cathy J. Wilson
Biogeosciences, 19, 1211–1223, https://doi.org/10.5194/bg-19-1211-2022, https://doi.org/10.5194/bg-19-1211-2022, 2022
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Planetary warming is increasing seasonal thaw of permafrost, making this extensive old carbon stock vulnerable. In northern Alaska, we found more and older dissolved organic carbon in small drainages later in summer as more permafrost was exposed by deepening thaw. Younger and older carbon did not differ in chemical indicators related to biological lability suggesting this carbon can cycle through aquatic systems and contribute to greenhouse gas emissions as warming increases permafrost thaw.
Pengzhi Zhao, Daniel Joseph Fallu, Sara Cucchiaro, Paolo Tarolli, Clive Waddington, David Cockcroft, Lisa Snape, Andreas Lang, Sebastian Doetterl, Antony G. Brown, and Kristof Van Oost
Biogeosciences, 18, 6301–6312, https://doi.org/10.5194/bg-18-6301-2021, https://doi.org/10.5194/bg-18-6301-2021, 2021
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We investigate the factors controlling the soil organic carbon (SOC) stability and temperature sensitivity of abandoned prehistoric agricultural terrace soils. Results suggest that the burial of former topsoil due to terracing provided an SOC stabilization mechanism. Both the soil C : N ratio and SOC mineral protection regulate soil SOC temperature sensitivity. However, which mechanism predominantly controls SOC temperature sensitivity depends on the age of the buried terrace soils.
Heleen Deroo, Masuda Akter, Samuel Bodé, Orly Mendoza, Haichao Li, Pascal Boeckx, and Steven Sleutel
Biogeosciences, 18, 5035–5051, https://doi.org/10.5194/bg-18-5035-2021, https://doi.org/10.5194/bg-18-5035-2021, 2021
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We assessed if and how incorporation of exogenous organic carbon (OC) such as straw could affect decomposition of native soil organic carbon (SOC) under different irrigation regimes. Addition of exogenous OC promoted dissolution of native SOC, partly because of increased Fe reduction, leading to more net release of Fe-bound SOC. Yet, there was no proportionate priming of SOC-derived DOC mineralisation. Water-saving irrigation can retard both priming of SOC dissolution and mineralisation.
Frances A. Podrebarac, Sharon A. Billings, Kate A. Edwards, Jérôme Laganière, Matthew J. Norwood, and Susan E. Ziegler
Biogeosciences, 18, 4755–4772, https://doi.org/10.5194/bg-18-4755-2021, https://doi.org/10.5194/bg-18-4755-2021, 2021
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Soil respiration is a large and temperature-responsive flux in the global carbon cycle. We found increases in microbial use of easy to degrade substrates enhanced the temperature response of respiration in soils layered as they are in situ. This enhanced response is consistent with soil composition differences in warm relative to cold climate forests. These results highlight the importance of the intact nature of soils rarely studied in regulating responses of CO2 fluxes to changing temperature.
Elisa Bruni, Bertrand Guenet, Yuanyuan Huang, Hugues Clivot, Iñigo Virto, Roberta Farina, Thomas Kätterer, Philippe Ciais, Manuel Martin, and Claire Chenu
Biogeosciences, 18, 3981–4004, https://doi.org/10.5194/bg-18-3981-2021, https://doi.org/10.5194/bg-18-3981-2021, 2021
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Increasing soil organic carbon (SOC) stocks is beneficial for climate change mitigation and food security. One way to enhance SOC stocks is to increase carbon input to the soil. We estimate the amount of carbon input required to reach a 4 % annual increase in SOC stocks in 14 long-term agricultural experiments around Europe. We found that annual carbon input should increase by 43 % under current temperature conditions, by 54 % for a 1 °C warming scenario and by 120 % for a 5 °C warming scenario.
Rainer Brumme, Bernd Ahrends, Joachim Block, Christoph Schulz, Henning Meesenburg, Uwe Klinck, Markus Wagner, and Partap K. Khanna
Biogeosciences, 18, 3763–3779, https://doi.org/10.5194/bg-18-3763-2021, https://doi.org/10.5194/bg-18-3763-2021, 2021
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In order to study the fate of litter nitrogen in forest soils, we combined a leaf litterfall exchange experiment using 15N-labeled leaf litter with long-term element budgets at seven European beech sites in Germany. It appears that fructification intensity, which has increased in recent decades, has a distinct impact on N retention in forest soils. Despite reduced nitrogen deposition, about 6 and 10 kg ha−1 of nitrogen were retained annually in the soils and in the forest stands, respectively.
Lorenz Gfeller, Andrea Weber, Isabelle Worms, Vera I. Slaveykova, and Adrien Mestrot
Biogeosciences, 18, 3445–3465, https://doi.org/10.5194/bg-18-3445-2021, https://doi.org/10.5194/bg-18-3445-2021, 2021
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Our incubation experiment shows that flooding of polluted floodplain soils may induce pulses of both mercury (Hg) and methylmercury to the soil solution and threaten downstream ecosystems. We demonstrate that mobilization of Hg bound to manganese oxides is a relevant process in organic-matter-poor soils. Addition of organic amendments accelerates this mobilization but also facilitates the formation of nanoparticulate Hg and the subsequent fixation of Hg from soil solution to the soil.
Yao Zhang, Jocelyn M. Lavallee, Andy D. Robertson, Rebecca Even, Stephen M. Ogle, Keith Paustian, and M. Francesca Cotrufo
Biogeosciences, 18, 3147–3171, https://doi.org/10.5194/bg-18-3147-2021, https://doi.org/10.5194/bg-18-3147-2021, 2021
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Soil organic matter (SOM) is essential for the health of soils, and the accumulation of SOM helps removal of CO2 from the atmosphere. Here we present the result of the continued development of a mathematical model that simulates SOM and its measurable fractions. In this study, we simulated several grassland sites in the US, and the model generally captured the carbon and nitrogen amounts in SOM and their distribution between the measurable fractions throughout the entire soil profile.
Zhongkui Luo, Raphael A. Viscarra-Rossel, and Tian Qian
Biogeosciences, 18, 2063–2073, https://doi.org/10.5194/bg-18-2063-2021, https://doi.org/10.5194/bg-18-2063-2021, 2021
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Using the data from 141 584 whole-soil profiles across the globe, we disentangled the relative importance of biotic, climatic and edaphic variables in controlling global SOC stocks. The results suggested that soil properties and climate contributed similarly to the explained global variance of SOC in four sequential soil layers down to 2 m. However, the most important individual controls are consistently soil-related, challenging current climate-driven framework of SOC dynamics.
Debjani Sihi, Xiaofeng Xu, Mónica Salazar Ortiz, Christine S. O'Connell, Whendee L. Silver, Carla López-Lloreda, Julia M. Brenner, Ryan K. Quinn, Jana R. Phillips, Brent D. Newman, and Melanie A. Mayes
Biogeosciences, 18, 1769–1786, https://doi.org/10.5194/bg-18-1769-2021, https://doi.org/10.5194/bg-18-1769-2021, 2021
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Humid tropical soils are important sources and sinks of methane. We used model simulation to understand how different kinds of microbes and observed soil moisture and oxygen dynamics contribute to production and consumption of methane along a wet tropical hillslope during normal and drought conditions. Drought alters the diffusion of oxygen and microbial substrates into and out of soil microsites, resulting in enhanced methane release from the entire hillslope during drought recovery.
Mathieu Chassé, Suzanne Lutfalla, Lauric Cécillon, François Baudin, Samuel Abiven, Claire Chenu, and Pierre Barré
Biogeosciences, 18, 1703–1718, https://doi.org/10.5194/bg-18-1703-2021, https://doi.org/10.5194/bg-18-1703-2021, 2021
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Evolution of organic carbon content in soils could be a major driver of atmospheric greenhouse gas concentrations over the next century. Understanding factors controlling carbon persistence in soil is a challenge. Our study of unique long-term bare-fallow samples, depleted in labile organic carbon, helps improve the separation, evaluation and characterization of carbon pools with distinct residence time in soils and gives insight into the mechanisms explaining soil organic carbon persistence.
Melisa A. Diaz, Christopher B. Gardner, Susan A. Welch, W. Andrew Jackson, Byron J. Adams, Diana H. Wall, Ian D. Hogg, Noah Fierer, and W. Berry Lyons
Biogeosciences, 18, 1629–1644, https://doi.org/10.5194/bg-18-1629-2021, https://doi.org/10.5194/bg-18-1629-2021, 2021
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Water-soluble salt and nutrient concentrations of soils collected along the Shackleton Glacier, Antarctica, show distinct geochemical gradients related to latitude, longitude, elevation, soil moisture, and distance from coast and glacier. Machine learning algorithms were used to estimate geochemical gradients for the region given the relationship with geography. Geography and surface exposure age drive salt and nutrient abundances, influencing invertebrate habitat suitability and biogeography.
Cited articles
Anderson, D. W. and Paul, E. A.: Organo-Mineral Complexes and Their Study by
Radiocarbon Dating, Soil Sci. Soc. Am. J., 48, 298–301,
https://doi.org/10.2136/sssaj1984.03615995004800020014x, 1984.
Angst, G., Mueller, K. E., Nierop, K. G. J., and Simpson, M. J.: Plant- or
microbial-derived? A review on the molecular composition of stabilized soil
organic matter, Soil Biol. Biochem., 156, 108189,
https://doi.org/10.1016/j.soilbio.2021.108189, 2021.
Baisden, W. T. and Canessa, S.: Using 50 years of soil radiocarbon data to
identify optimal approaches for estimating soil carbon residence times, Nucl.
Instrum. Method. Phys. Res. B, 294, 588–592,
https://doi.org/10.1016/j.nimb.2012.06.021, 2013.
Balesdent, J.: The turnover of soil organic fractions estimated by
radiocarbon dating, Sci. Total Environ., 62, 405–408,
https://doi.org/10.1016/0048-9697(87)90528-6, 1987.
Basile-Doelsch, I., Balesdent, J., and Pellerin, S.: Reviews and syntheses:
The mechanisms underlying carbon storage in soil, Biogeosciences, 17,
5223–5242, https://doi.org/10.5194/bg-17-5223-2020, 2020.
Bianchi, T. S., Galy, V., Rosenheim, B. E., Shields, M., Cui, X., and Van
Metre, P.: Paleoreconstruction of organic carbon inputs to an oxbow lake in
the Mississippi River watershed: Effects of dam construction and land use
change on regional inputs, Geophys. Res. Lett., 42, 7983–7991,
https://doi.org/10.1002/2015GL065595, 2015.
Bolin, B. and Rodhe, H.: A note on the concepts of age distribution and
transit time in natural reservoirs, Tellus, 25, 58–62,
https://doi.org/10.1111/j.2153-3490.1973.tb01594.x, 1973.
Bosatta, E. and Ågren, G. I.: Theoretical analysis of decomposition of
heterogeneous substrates, Soil Biol. Biochem., 17, 601–610,
https://doi.org/10.1016/0038-0717(85)90035-5, 1985.
Castanha, C., Trumbore, S., and Amundson, R.: Methods of separating soil
carbon pools affect the chemistry and turnover time of isolated fractions,
Radiocarbon, 50, 83–97, https://doi.org/10.1017/S0033822200043381, 2008.
Chanca, I., Trumbore, S., Macario, K., and Sierra, C. A.: Probability
Distributions of Radiocarbon in Open Linear Compartmental Systems at
Steady-State, J. Geophys. Res.-Biogeo., 127, 1–23,
https://doi.org/10.1029/2021JG006673, 2022.
Cotrufo, M. F., Ranalli, M. G., Haddix, M. L., Six, J., and Lugato, E.: Soil
carbon storage informed by particulate and mineral-associated organic
matter, Nat. Geosci., 12, 989–994, https://doi.org/10.1038/s41561-019-0484-6,
2019.
Cusack, D. F., Chadwick, O. A., Hockaday, W. C., and Vitousek, P. M.:
Mineralogical controls on soil black carbon preservation, Global Biogeochem.
Cy., 26, 1–10, https://doi.org/10.1029/2011GB004109, 2012.
Dahiya, J. B. and Rana, S.: Thermal degradation and morphological studies on
cotton cellulose modified with various arylphosphorodichloridites, Polym.
Int., 53, 995–1002, https://doi.org/10.1002/pi.1500, 2004.
De Coninck, F.: Major mechanisms in formation of spodic horizons, Geoderma,
24, 101–128, 1980.
Feng, X. and Simpson, M. J.: Temperature responses of individual soil
organic matter components, J. Geophys. Res.-Biogeo., 113, 1–14,
https://doi.org/10.1029/2008JG000743, 2008.
González-Pérez, J. A., Chabbi, A., de la Rosa, J. M., Rumpel, C.,
and González-Vila, F. J.: Evolution of organic matter in
lignite-containing sediments revealed by analytical pyrolysis (Py-GC-MS),
Org. Geochem., 53, 119–130, https://doi.org/10.1016/j.orggeochem.2012.08.001,
2012.
Grandy, A. S., Strickland, M. S., Lauber, C. L., Bradford, M. A., and
Fierer, N.: The influence of microbial communities, management, and soil
texture on soil organic matter chemistry, Geoderma, 150, 278–286,
https://doi.org/10.1016/j.geoderma.2009.02.007, 2009.
Grant, K. E., Galy, V. V., Chadwick, O. A., and Derry, L. A.: Thermal
oxidation of carbon in organic matter rich volcanic soils: insights into SOC
age differentiation and mineral stabilization, Biogeochemistry, 144,
291–304, https://doi.org/10.1007/s10533-019-00586-1, 2019.
Grant, K. E., Hilton, R. G., and Galy, V.: Global patterns of radiocarbon
depletion in subsoil linked to rock-derived organic carbon, Geochem. Perspect.
Lett., 25, 36–40, 2023.
Gregorich, E. G., Beare, M. H., McKim, U. F., and Skjemstad, J. O.: Chemical
and Biological Characteristics of Physically Uncomplexed Organic Matter,
Soil Sci. Soc. Am. J., 70, 975–985,
https://doi.org/10.2136/sssaj2005.0116, 2006.
Heckman, K., Lawrence, C. R., and Harden, J. W.: A sequential selective
dissolution method to quantify storage and stability of organic carbon
associated with Al and Fe hydroxide phases, Geoderma, 312, 24–35,
https://doi.org/10.1016/j.geoderma.2017.09.043, 2018a.
Heckman, K., Throckmorton, H., Horwath, W., Swanston, C., and Rasmussen, C.:
Variation in the Molecular Structure and Radiocarbon Abundance of
Mineral-Associated Organic Matter across a Lithosequence of Forest Soils,
Soil Syst., 2, 36, https://doi.org/10.3390/soilsystems2020036, 2018b.
Heckman, K., Hicks Pries, C. E., Lawrence, C. R., Rasmussen, C., Crow, S.
E., Hoyt, A. M., von Fromm, S. F., Shi, Z., Stoner, S., McGrath, C.,
Beem-Miller, J., Berhe, A. A., Blankinship, J. C., Keiluweit, M.,
Marín-Spiotta, E., Monroe, J. G., Plante, A. F., Schimel, J., Sierra,
C. A., Thompson, A., and Wagai, R.: Beyond bulk: Density fractions explain
heterogeneity in global soil carbon abundance and persistence, Glob. Change
Biol., 28, 1178–1196, https://doi.org/10.1111/gcb.16023, 2022.
Helfrich, M., Flessa, H., Mikutta, R., Dreves, A., and Ludwig, B.:
Comparison of chemical fractionation methods for isolating stable soil
organic carbon pools, Eur. J. Soil Sci., 58, 1316–1329,
https://doi.org/10.1111/j.1365-2389.2007.00926.x, 2007.
Hemingway, J. D.: rampedpyrox: Open-source tools for thermoanalytical data
analysis, https://github.com/FluvialSeds/rampedpyrox (last access: 20 June 2022), 2016.
Hemingway, J. D., Rothman, D. H., Rosengard, S. Z., and Galy, V. V.:
Technical note: An inverse method to relate organic carbon reactivity to
isotope composition from serial oxidation, Biogeosciences, 14, 5099–5114,
https://doi.org/10.5194/bg-14-5099-2017, 2017.
Hemingway, J. D., Rothman, D. H., Grant, K. E., Rosengard, S. Z., Eglinton,
T. I., Derry, L. A., and Galy, V. V.: Mineral protection regulates long-term
global preservation of natural organic carbon, Nature, 570, 228–231,
https://doi.org/10.1038/s41586-019-1280-6, 2019.
Huang, X., Jiang, H., Li, Y., Ma, Y., Tang, H., Ran, W., and Shen, Q.: The
role of poorly crystalline iron oxides in the stability of soil
aggregate-associated organic carbon in a rice-wheat cropping system,
Geoderma, 279, 1–10, https://doi.org/10.1016/j.geoderma.2016.05.011, 2016.
Jagadamma, S., Lal, R., Ussiri, D. A. N., Trumbore, S. E., and Mestelan, S.:
Evaluation of structural chemistry and isotopic signatures of refractory
soil organic carbon fraction isolated by wet oxidation methods,
Biogeochemistry, 98, 29–44, https://doi.org/10.1007/s10533-009-9374-0,
2010.
Kaiser, K., Mikutta, R., and Guggenberger, G.: Increased Stability of
Organic Matter Sorbed to Ferrihydrite and Goethite on Aging, Soil Sci.
Soc. Am. J., 71, 711–719,
https://doi.org/10.2136/sssaj2006.0189, 2007.
Khomo, L., Trumbore, S., Bern, C. R., and Chadwick, O. A.: Timescales of
carbon turnover in soils with mixed crystalline mineralogies, Soil, 3,
17–30, https://doi.org/10.5194/soil-3-17-2017, 2017.
Kleber, M., Bourg, I. C., Coward, E. K., Hansel, C. M., Myneni, S. C. B.,
and Nunan, N.: Dynamic interactions at the mineral–organic matter
interface, Nat. Rev. Earth Environ., 1, 0123456789,
https://doi.org/10.1038/s43017-021-00162-y, 2021.
Lavallee, J. M., Soong, J. L., and Cotrufo, M. F.: Conceptualizing soil
organic matter into particulate and mineral-associated forms to address
global change in the 21st century, Glob. Change Biol., 26, 261–273,
https://doi.org/10.1111/gcb.14859, 2020.
Lehmann, J. and Kleber, M.: The contentious nature of soil organic matter,
Nature, 528, 60–68, https://doi.org/10.1038/nature16069, 2015.
Leifeld, J. and von Lützow, M.: Chemical and microbial activation
energies of soil organic matter decomposition, Biol. Fertil. Soils, 50,
147–153, https://doi.org/10.1007/s00374-013-0822-6, 2014.
Metzler, H., Müller, M., and Sierra, C. A.: Transit-time and age
distributions for nonlinear time-dependent compartmental systems, P. Natl.
Acad. Sci. USA, 115, 1150–1155, https://doi.org/10.1073/pnas.1705296115,
2018.
Mikutta, R. and Kaiser, K.: Organic matter bound to mineral surfaces:
Resistance to chemical and biological oxidation, Soil Biol. Biochem., 43,
1738–1741, https://doi.org/10.1016/j.soilbio.2011.04.012, 2011.
Natali, C., Bianchini, G., and Carlino, P.: Thermal stability of soil carbon
pools: Inferences on soil nature and evolution, Thermochim. Ac., 683,
178478, https://doi.org/10.1016/j.tca.2019.178478, 2020.
Nkwain, F. N., Demyan, M. S., Rasche, F., Dignac, M. F., Schulz, E.,
Kätterer, T., Müller, T., and Cadisch, G.: Coupling pyrolysis with
mid-infrared spectroscopy (Py-MIRS) to fingerprint soil organic matter bulk
chemistry, J. Anal. Appl. Pyrolysis., 133, 176–184,
https://doi.org/10.1016/j.jaap.2018.04.004, 2018.
Paul, E. A., Follett, R. F., Leavitt, S. W., Halvorson, A., Peterson, G. A.,
and Lyon, D. J.: Radiocarbon Dating for Determination of Soil Organic Matter
Pool Sizes and Dynamics, Soil Sci. Soc. Am. J., 61,
1058–1067, https://doi.org/10.2136/sssaj1997.03615995006100040011x, 1997.
Plante, A. F., Fernández, J. M., and Leifeld, J.: Application of thermal
analysis techniques in soil science, Geoderma, 153, 1–10,
https://doi.org/10.1016/j.geoderma.2009.08.016, 2009.
Plante, A. F., Fernández, J. M., Haddix, M. L., Steinweg, J. M., and
Conant, R. T.: Biological, chemical and thermal indices of soil organic
matter stability in four grassland soils, Soil Biol. Biochem., 43, 1051–1058,
https://doi.org/10.1016/j.soilbio.2011.01.024, 2011.
Plante, A. F., Beaupré, S. R., Roberts, M. L., and Baisden, T.:
Distribution of Radiocarbon Ages in Soil Organic Matter by Thermal
Fractionation, Radiocarbon, 55, 1077–1083,
https://doi.org/10.1017/s0033822200058215, 2013.
Quénéa, K., Derenne, S., González-Vila, F. J.,
González-Pérez, J. A., Mariotti, A., and Largeau, C.: Double-shot
pyrolysis of the non-hydrolysable organic fraction isolated from a sandy
forest soil (Landes de Gascogne, South-West France): Comparison with
classical Curie point pyrolysis, J. Anal. Appl. Pyrolysis., 76, 271–279,
https://doi.org/10.1016/j.jaap.2005.12.007, 2006.
Rasmussen, C., Throckmorton, H., Liles, G., Heckman, K., Meding, S., and
Horwath, W. R.: Controls on soil organic carbon partitioning and
stabilization in the California Sierra Nevada, Soil Syst., 2, 1–18,
https://doi.org/10.3390/soilsystems2030041, 2018.
Rennert, T. and Herrmann, L.: Sea spray and land use effects on clay
minerals and organic matter of soils on machair (Harris, Scotland), Geoderma
Reg., 23, e00339, https://doi.org/10.1016/j.geodrs.2020.e00339, 2020.
Rennert, T. and Herrmann, L.: Thermal-gradient analysis of soil organic
matter using an elemental analyser – A tool for qualitative
characterization?, Geoderma, 425, 116085,
https://doi.org/10.1016/j.geoderma.2022.116085, 2022.
Rosenheim, B. E. and Galy, V.: Direct measurement of riverine particulate
organic carbon age structure, Geophys. Res. Lett., 39, 1–6,
https://doi.org/10.1029/2012GL052883, 2012.
Rosenheim, B. E., Day, M. B., Domack, E., Schrum, H., Benthien, A., and
Hayes, J. M.: Antarctic sediment chronology by programmed-temperature
pyrolysis: Methodology and data treatment, Geochem. Geophy.
Geosy., 9, 1–16, https://doi.org/10.1029/2007GC001816, 2008.
Sanderman, J. and Grandy, S. A.: Ramped thermal analysis for isolating
biologically meaningful soil organic matter fractions with distinct
residence times, Soil, 6, 131–144, https://doi.org/10.5194/soil-6-131-2020,
2020.
Sanderman, J., Baisden, W. T., and Fallon, S.: Redefining the inert organic
carbon pool, Soil Biol. Biochem., 92, 149–152,
https://doi.org/10.1016/j.soilbio.2015.10.005, 2016.
Schrumpf, M., Schulze, E. D., Kaiser, K., and Schumacher, J.: How accurately
can soil organic carbon stocks and stock changes be quantified by soil
inventories?, Biogeosciences, 8, 1193–1212,
https://doi.org/10.5194/bg-8-1193-2011, 2011.
Schrumpf, M., Kaiser, K., Guggenberger, G., Persson, T., Kögel-Knabner,
I., and Schulze, E. D.: Storage and stability of organic carbon in soils as
related to depth, occlusion within aggregates, and attachment to minerals,
Biogeosciences, 10, 1675–1691, https://doi.org/10.5194/bg-10-1675-2013,
2013.
Schrumpf, M., Kaiser, K., Mayer, A., Hempel, G., and Trumbore, S.: Age
distribution, extractability, and stability of mineral-bound organic carbon
in central European soils, Biogeosciences, 18, 1241–1257,
https://doi.org/10.5194/bg-18-1241-2021, 2021.
Schuur, E. A. G., Trumbore, S. E., and Druffel, E. R. M.: Radiocarbon and
Climate Change: Mechanisms, Appl. Laborat. Tech., 1, 1–315, https://doi.org/10.1007/978-3-319-25643-6, 2016.
Seifert, A. G., Trumbore, S., Xu, X., Zhang, D., and Gleixner, G.: Variable
effects of plant colonization on black slate uptake into microbial PLFAs,
Geochim. Cosmochim. Ac., 106, 391–403,
https://doi.org/10.1016/j.gca.2012.12.011, 2013.
Sierra, C. A., Müller, M., and Trumbore, S. E.: Modeling radiocarbon
dynamics in soils: SoilR version 1.1, Geosci. Model. Dev., 7, 1919–1931,
https://doi.org/10.5194/gmd-7-1919-2014, 2014.
Sierra, C. A., Hoyt, A. M., He, Y., and Trumbore, S. E.: Soil Organic Matter
Persistence as a Stochastic Process: Age and Transit Time Distributions of
Carbon in Soils, Global Biogeochem. Cy., 32, 1574–1588,
https://doi.org/10.1029/2018GB005950, 2018.
Sollins, P., Kramer, M. G., Swanston, C., Lajtha, K., Filley, T.,
Aufdenkampe, A. K., Wagai, R., and Bowden, R. D.: Sequential density
fractionation across soils of contrasting mineralogy: Evidence for both
microbial- and mineral-controlled soil organic matter stabilization,
Biogeochemistry, 96, 209–231, https://doi.org/10.1007/s10533-009-9359-z,
2009.
Stoner, S.: ShaneStoner/BGS_ThermalFractionation: Publication, v1.0, Zenodo [data set and code],
https://doi.org/10.5281/zenodo.7998659, 2023.
Torn, M. S., Trumbore, S. E., Chadwick, O. A., Vitousek, P. M., and
Hendricks, D. M.: Mineral control of soil organic carbon and storage and
turnover, Nature, 389, 3601–3603, 1997.
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.
Trumbore, S. E.: Comparisons of carbon dynamics in tropical and temperate
soils using radiocarbon measurements, Measurement, 7, 275–290, 1993.
Trumbore, S. E. and Zheng, S.: Comparison of fractionation methods for soil
organic matter 14C analysis, Radiocarbon, 38, 219–229, https://doi.org/10.1017/S0033822200017598, 1996.
Trumbore, S. E., Bonani, G., and Wolfli, W.: The rates of carbon cycling in
several soils from AMS14C measurements of fractionated soil organic matter, in: Soils and the greenhouse effect, Vol. 23, 407–414,
John Wiley and Sons Inc, New York, USA, 575 pp., ISBN 0-471-92358-8, 1990.
von Lützow, M., Kögel-Knabner, I., Ekschmitt, K., Flessa, H.,
Guggenberger, G., Matzner, E., and Marschner, B.: SOM fractionation methods:
Relevance to functional pools and to stabilization mechanisms, Soil Biol.
Biochem., 39, 2183–2207, https://doi.org/10.1016/j.soilbio.2007.03.007,
2007.
Wendeberg, M., Richter, J. M., Rothe, M., and Brand, W. A.: Jena Reference
Air Set (JRAS): A multi-point scale anchor for isotope measurements of CO2 in
air, Atmos. Meas. Tech., 6, 817–822, https://doi.org/10.5194/amt-6-817-2013,
2013.
Williams, E. K., Fogel, M. L., Berhe, A. A., and Plante, A. F.: Distinct
bioenergetic signatures in particulate versus mineral-associated soil
organic matter, Geoderma, 330, 107–116,
https://doi.org/10.1016/j.geoderma.2018.05.024, 2018.
Xu, X., Trumbore, S. E., Zheng, S., Southon, J. R., McDuffee, K. E.,
Luttgen, M., and Liu, J. C.: Modifying a sealed tube zinc reduction method
for preparation of AMS graphite targets: Reducing background and attaining
high precision, Nucl. Instrum. Method. Phys. Res. B, 259, 320–329,
https://doi.org/10.1016/j.nimb.2007.01.175, 2007.
Short summary
Soils store more carbon (C) than any other terrestrial C reservoir, but the processes that control how much C stays in soil, and for how long, are very complex. Here, we used a recent method that involves heating soil in the lab to measure the range of C ages in soil. We found that most C in soil is decades to centuries old, while some stays for much shorter times (days to months), and some is thousands of years old. Such detail helps us to estimate how soil C may react to changing climate.
Soils store more carbon (C) than any other terrestrial C reservoir, but the processes that...
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