Articles | Volume 7, issue 2
https://doi.org/10.5194/soil-7-693-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/soil-7-693-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Original research article
| 
26 Oct 2021
Original research article |
| 26 Oct 2021
| 26 Oct 2021
The central African soil spectral library: a new soil infrared repository and a geographical prediction analysis
Laura Summerauer
CORRESPONDING AUTHOR
Department of Environmental Systems Science, ETH Zurich, Zurich Switzerland
Philipp Baumann
Department of Environmental Systems Science, ETH Zurich, Zurich Switzerland
Leonardo Ramirez-Lopez
Data Science Department, BUCHI Labortechnik AG, Flawil, Switzerland
Matti Barthel
Department of Environmental Systems Science, ETH Zurich, Zurich Switzerland
Marijn Bauters
Department of Green Chemistry and Technology, Ghent University, Ghent, Belgium
Department of Environment, Ghent University, Ghent, Belgium
Benjamin Bukombe
Institute of Geography, University of Augsburg, Augsburg, Germany
Mario Reichenbach
Institute of Geography, University of Augsburg, Augsburg, Germany
Pascal Boeckx
Department of Green Chemistry and Technology, Ghent University, Ghent, Belgium
Elizabeth Kearsley
Department of Environment, Ghent University, Ghent, Belgium
Kristof Van Oost
Earth and Life Institute, UCLouvain, Louvain-la-Neuve, Belgium
Bernard Vanlauwe
International Institute of Tropical Agriculture, Nairobi, Kenya
Dieudonné Chiragaga
International Institute of Tropical Agriculture, Bukavu, Democratic Republic of Congo
Aimé Bisimwa Heri-Kazi
Earth and Life Institute, UCLouvain, Louvain-la-Neuve, Belgium
Pieter Moonen
Department of Earth and Environmental Sciences, KU Leuven, Leuven, Belgium
Andrew Sila
World Agroforestry Centre, Nairobi, Kenya
Keith Shepherd
World Agroforestry Centre, Nairobi, Kenya
Basile Bazirake Mujinya
Department of General Agricultural Sciences, University of Lubumbashi, Lubumbashi, Democratic Republic of Congo
Eric Van Ranst
Department of Geology, Ghent University, Ghent, Belgium
Geert Baert
Department of Green Chemistry and Technology, Ghent University, Ghent, Belgium
Sebastian Doetterl
Department of Environmental Systems Science, ETH Zurich, Zurich Switzerland
Institute of Geography, University of Augsburg, Augsburg, Germany
Johan Six
Department of Environmental Systems Science, ETH Zurich, Zurich Switzerland
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Vira Leng, Rémi Cardinael, Florent Tivet, Vang Seng, Phearum Mark, Pascal Lienhard, Titouan Filloux, Johan Six, Lyda Hok, Stéphane Boulakia, Clever Briedis, João Carlos de Moraes Sá, and Laurent Thuriès
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Moritz Laub, Magdalena Necpalova, Marijn Van de Broek, Marc Corbeels, Samuel Mathu Ndungu, Monicah Wanjiku Mucheru-Muna, Daniel Mugendi, Rebecca Yegon, Wycliffe Waswa, Bernard Vanlauwe, and Johan Six
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Claude Raoul Müller, Johan Six, Liesa Brosens, Philipp Baumann, Jean Paolo Gomes Minella, Gerard Govers, and Marijn Van de Broek
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Johan Six, Sebastian Doetterl, Moritz Laub, Claude R. Müller, and Marijn Van de Broek
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SOIL, 10, 231–249, https://doi.org/10.5194/soil-10-231-2024, https://doi.org/10.5194/soil-10-231-2024, 2024
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Armwell Shumba, Regis Chikowo, Christian Thierfelder, Marc Corbeels, Johan Six, and Rémi Cardinael
SOIL, 10, 151–165, https://doi.org/10.5194/soil-10-151-2024, https://doi.org/10.5194/soil-10-151-2024, 2024
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Moritz Laub, Sergey Blagodatsky, Marijn Van de Broek, Samuel Schlichenmaier, Benjapon Kunlanit, Johan Six, Patma Vityakon, and Georg Cadisch
Geosci. Model Dev., 17, 931–956, https://doi.org/10.5194/gmd-17-931-2024, https://doi.org/10.5194/gmd-17-931-2024, 2024
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Gina Garland, John Koestel, Alice Johannes, Olivier Heller, Sebastian Doetterl, Dani Or, and Thomas Keller
SOIL, 10, 23–31, https://doi.org/10.5194/soil-10-23-2024, https://doi.org/10.5194/soil-10-23-2024, 2024
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The concept of soil aggregates is hotly debated, leading to confusion about their function or relevancy to soil processes. We propose that the use of conceptual figures showing detached and isolated aggregates can be misleading and has contributed to this skepticism. Here, we conceptually illustrate how aggregates can form and dissipate within the context of undisturbed soils, highlighting the fact that aggregates do not necessarily need to have distinct physical boundaries.
Shane W. Stoner, Marion Schrumpf, Alison Hoyt, Carlos A. Sierra, Sebastian Doetterl, Valier Galy, and Susan Trumbore
Biogeosciences, 20, 3151–3163, https://doi.org/10.5194/bg-20-3151-2023, https://doi.org/10.5194/bg-20-3151-2023, 2023
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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.
Moritz Laub, Marc Corbeels, Antoine Couëdel, Samuel Mathu Ndungu, Monicah Wanjiku Mucheru-Muna, Daniel Mugendi, Magdalena Necpalova, Wycliffe Waswa, Marijn Van de Broek, Bernard Vanlauwe, and Johan Six
SOIL, 9, 301–323, https://doi.org/10.5194/soil-9-301-2023, https://doi.org/10.5194/soil-9-301-2023, 2023
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In sub-Saharan Africa, long-term low-input maize cropping threatens soil fertility. We studied how different quality organic inputs combined with mineral N fertilizer could counteract this. Farmyard manure was the best input to counteract soil carbon loss; mineral N fertilizer had no effect on carbon. Yet, the rates needed to offset soil carbon losses are unrealistic for farmers (>10 t of dry matter per hectare and year). Additional agronomic measures may be needed.
Kristof Van Oost and Johan Six
Biogeosciences, 20, 635–646, https://doi.org/10.5194/bg-20-635-2023, https://doi.org/10.5194/bg-20-635-2023, 2023
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The direction and magnitude of the net erosion-induced land–atmosphere C exchange have been the topic of a big scientific debate for more than a decade now. Many have assumed that erosion leads to a loss of soil carbon to the atmosphere, whereas others have shown that erosion ultimately leads to a carbon sink. Here, we show that the soil carbon erosion source–sink paradox is reconciled when the broad range of temporal and spatial scales at which the underlying processes operate are considered.
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.
Charlotte Decock, Juhwan Lee, Matti Barthel, Elizabeth Verhoeven, Franz Conen, and Johan Six
Biogeosciences Discuss., https://doi.org/10.5194/bg-2022-221, https://doi.org/10.5194/bg-2022-221, 2022
Preprint withdrawn
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One of the least well understood processes in the nitrogen (N) cycle is the loss of nitrogen gas (N2), referred to as total denitrification. This is mainly due to the difficulty of quantifying total denitrification in situ. In this study, we developed and tested a novel modeling approach to estimate total denitrification over the depth profile, based on concentrations and isotope values of N2O. Our method will help close N budgets and identify management strategies that reduce N pollution.
Flossie Brown, Gerd A. Folberth, Stephen Sitch, Susanne Bauer, Marijn Bauters, Pascal Boeckx, Alexander W. Cheesman, Makoto Deushi, Inês Dos Santos Vieira, Corinne Galy-Lacaux, James Haywood, James Keeble, Lina M. Mercado, Fiona M. O'Connor, Naga Oshima, Kostas Tsigaridis, and Hans Verbeeck
Atmos. Chem. Phys., 22, 12331–12352, https://doi.org/10.5194/acp-22-12331-2022, https://doi.org/10.5194/acp-22-12331-2022, 2022
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Surface ozone can decrease plant productivity and impair human health. In this study, we evaluate the change in surface ozone due to climate change over South America and Africa using Earth system models. We find that if the climate were to change according to the worst-case scenario used here, models predict that forested areas in biomass burning locations and urban populations will be at increasing risk of ozone exposure, but other areas will experience a climate benefit.
Haicheng Zhang, Ronny Lauerwald, Pierre Regnier, Philippe Ciais, Kristof Van Oost, Victoria Naipal, Bertrand Guenet, and Wenping Yuan
Earth Syst. Dynam., 13, 1119–1144, https://doi.org/10.5194/esd-13-1119-2022, https://doi.org/10.5194/esd-13-1119-2022, 2022
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We present a land surface model which can simulate the complete lateral transfer of sediment and carbon from land to ocean through rivers. Our model captures the water, sediment, and organic carbon discharges in European rivers well. Application of our model in Europe indicates that lateral carbon transfer can strongly change regional land carbon budgets by affecting organic carbon distribution and soil moisture.
Tegawende Léa Jeanne Ilboudo, Lucien NGuessan Diby, Delwendé Innocent Kiba, Tor Gunnar Vågen, Leigh Ann Winowiecki, Hassan Bismarck Nacro, Johan Six, and Emmanuel Frossard
EGUsphere, https://doi.org/10.5194/egusphere-2022-209, https://doi.org/10.5194/egusphere-2022-209, 2022
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Our results showed that at landscape level SOC stock variability was mainly explained by clay content. We found significant linear positive relationships between VC and SOC stocks for the land uses annual croplands, perennial croplands, grasslands and bushlands without soil depth restrictions until 110 cm. We concluded that in the forest-savanna transition zone, soil properties and topography determine land use, which in turn affects the stocks of SOC and TN and to some extent the VC stocks.
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.
Caroline C. Clason, Will H. Blake, Nick Selmes, Alex Taylor, Pascal Boeckx, Jessica Kitch, Stephanie C. Mills, Giovanni Baccolo, and Geoffrey E. Millward
The Cryosphere, 15, 5151–5168, https://doi.org/10.5194/tc-15-5151-2021, https://doi.org/10.5194/tc-15-5151-2021, 2021
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Our paper presents results of sample collection and subsequent geochemical analyses from the glaciated Isfallsglaciären catchment in Arctic Sweden. The data suggest that material found on the surface of glaciers,
cryoconite, is very efficient at accumulating products of nuclear fallout transported in the atmosphere following events such as the Chernobyl disaster. We investigate how this compares with samples in the downstream environment and consider potential environmental implications.
Philipp Baumann, Juhwan Lee, Emmanuel Frossard, Laurie Paule Schönholzer, Lucien Diby, Valérie Kouamé Hgaza, Delwende Innocent Kiba, Andrew Sila, Keith Sheperd, and Johan Six
SOIL, 7, 717–731, https://doi.org/10.5194/soil-7-717-2021, https://doi.org/10.5194/soil-7-717-2021, 2021
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This work delivers openly accessible and validated calibrations for diagnosing 26 soil properties based on mid-infrared spectroscopy. These were developed for four regions in Burkina Faso and Côte d'Ivoire, including 80 fields of smallholder farmers. The models can help to site-specifically and cost-efficiently monitor soil quality and fertility constraints to ameliorate soils and yields of yam or other staple crops in the four regions between the humid forest and the northern Guinean savanna.
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.
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.
Lander Van Tricht, Philippe Huybrechts, Jonas Van Breedam, Alexander Vanhulle, Kristof Van Oost, and Harry Zekollari
The Cryosphere, 15, 4445–4464, https://doi.org/10.5194/tc-15-4445-2021, https://doi.org/10.5194/tc-15-4445-2021, 2021
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We conducted innovative research on the use of drones to determine the surface mass balance (SMB) of two glaciers. Considering appropriate spatial scales, we succeeded in determining the SMB in the ablation area with large accuracy. Consequently, we are convinced that our method and the use of drones to monitor the mass balance of a glacier’s ablation area can be an add-on to stake measurements in order to obtain a broader picture of the heterogeneity of the SMB of glaciers.
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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The African Tropics are hotspots of modern-day land use change and are of great relevance for the global carbon cycle. Here, we present data collected as part of the DFG-funded project TropSOC along topographic, land use, and geochemical gradients in the eastern Congo Basin and the Albertine Rift. Our database contains spatial and temporal data on soil, vegetation, environmental properties, and land management collected from 136 pristine tropical forest and cropland plots between 2017 and 2020.
Philipp Baumann, Anatol Helfenstein, Andreas Gubler, Armin Keller, Reto Giulio Meuli, Daniel Wächter, Juhwan Lee, Raphael Viscarra Rossel, and Johan Six
SOIL, 7, 525–546, https://doi.org/10.5194/soil-7-525-2021, https://doi.org/10.5194/soil-7-525-2021, 2021
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We developed the Swiss mid-infrared spectral library and a statistical model collection across 4374 soil samples with reference measurements of 16 properties. Our library incorporates soil from 1094 grid locations and 71 long-term monitoring sites. This work confirms once again that nationwide spectral libraries with diverse soils can reliably feed information to a fast chemical diagnosis. Our data-driven reduction of the library has the potential to accurately monitor carbon at the plot scale.
Mario Reichenbach, Peter Fiener, Gina Garland, Marco Griepentrog, Johan Six, and Sebastian Doetterl
SOIL, 7, 453–475, https://doi.org/10.5194/soil-7-453-2021, https://doi.org/10.5194/soil-7-453-2021, 2021
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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.
Anatol Helfenstein, Philipp Baumann, Raphael Viscarra Rossel, Andreas Gubler, Stefan Oechslin, and Johan Six
SOIL, 7, 193–215, https://doi.org/10.5194/soil-7-193-2021, https://doi.org/10.5194/soil-7-193-2021, 2021
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In this study, we show that a soil spectral library (SSL) can be used to predict soil carbon at new and very different locations. The importance of this finding is that it requires less time-consuming lab work than calibrating a new model for every local application, while still remaining similar to or more accurate than local models. Furthermore, we show that this method even works for predicting (drained) peat soils, using a SSL with mostly mineral soils containing much less soil carbon.
Simon Baumgartner, Marijn Bauters, Matti Barthel, Travis W. Drake, Landry C. Ntaboba, Basile M. Bazirake, Johan Six, Pascal Boeckx, and Kristof Van Oost
SOIL, 7, 83–94, https://doi.org/10.5194/soil-7-83-2021, https://doi.org/10.5194/soil-7-83-2021, 2021
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We compared stable isotope signatures of soil profiles in different forest ecosystems within the Congo Basin to assess ecosystem-level differences in N cycling, and we examined the local effect of topography on the isotopic signature of soil N. Soil δ15N profiles indicated that the N cycling in in the montane forest is more closed, whereas the lowland forest and Miombo woodland experienced a more open N cycle. Topography only alters soil δ15N values in forests with high erosional forces.
Paula Alejandra Lamprea Pineda, Marijn Bauters, Hans Verbeeck, Selene Baez, Matti Barthel, Samuel Bodé, and Pascal Boeckx
Biogeosciences, 18, 413–421, https://doi.org/10.5194/bg-18-413-2021, https://doi.org/10.5194/bg-18-413-2021, 2021
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Tropical forest soils are an important source and sink of greenhouse gases (GHGs) with tropical montane forests having been poorly studied. In this pilot study, we explored soil fluxes of CO2, CH4, and N2O in an Ecuadorian neotropical montane forest, where a net consumption of N2O at higher altitudes was observed. Our results highlight the importance of short-term variations in N2O and provide arguments and insights for future, more detailed studies on GHG fluxes from montane forest soils.
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.
Zhengang Wang, Jianxiu Qiu, and Kristof Van Oost
Geosci. Model Dev., 13, 4977–4992, https://doi.org/10.5194/gmd-13-4977-2020, https://doi.org/10.5194/gmd-13-4977-2020, 2020
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This study developed a spatially distributed carbon cycling model applicable in an eroding landscape. It includes all three carbon isotopes so that it is able to represent the carbon isotopic compositions. The model is able to represent the observations that eroding area is enriched in 13C and depleted of 14C compared to depositional area. Our simulations show that the spatial variability of carbon isotopic properties in an eroding landscape is mainly caused by the soil redistribution.
Hannes P. T. De Deurwaerder, Marco D. Visser, Matteo Detto, Pascal Boeckx, Félicien Meunier, Kathrin Kuehnhammer, Ruth-Kristina Magh, John D. Marshall, Lixin Wang, Liangju Zhao, and Hans Verbeeck
Biogeosciences, 17, 4853–4870, https://doi.org/10.5194/bg-17-4853-2020, https://doi.org/10.5194/bg-17-4853-2020, 2020
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The depths at which plants take up water is challenging to observe directly. To do so, scientists have relied on measuring the isotopic composition of xylem water as this provides information on the water’s source. Our work shows that this isotopic composition changes throughout the day, which complicates the interpretation of the water’s source and has been currently overlooked. We build a model to help understand the origin of these composition changes and their consequences for science.
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Short summary
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.
We present a soil mid-infrared library with over 1800 samples from central Africa in order to...
