Articles | Volume 1, issue 2
https://doi.org/10.5194/soil-1-707-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/soil-1-707-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Effect of biochar and liming on soil nitrous oxide emissions from a temperate maize cropping system
R. Hüppi
Climate and Air Pollution Group, Agroscope Institute for SustaInability Sciences, Zurich, Switzerland
Department of Environmental Science, Institute of Agricultural Sciences, ETH Zurich, Zurich, Switzerland
R. Felber
Climate and Air Pollution Group, Agroscope Institute for SustaInability Sciences, Zurich, Switzerland
A. Neftel
Climate and Air Pollution Group, Agroscope Institute for SustaInability Sciences, Zurich, Switzerland
Department of Environmental Science, Institute of Agricultural Sciences, ETH Zurich, Zurich, Switzerland
J. Leifeld
Climate and Air Pollution Group, Agroscope Institute for SustaInability Sciences, 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
SOIL, 10, 699–725, https://doi.org/10.5194/soil-10-699-2024, https://doi.org/10.5194/soil-10-699-2024, 2024
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We assessed the long-term impacts of no-till cropping systems on soil organic carbon and nitrogen dynamics down to 1 m depth under the annual upland crop productions (cassava, maize, and soybean) in the tropical climate of Cambodia. We showed that no-till systems combined with rotations and cover crops could store large amounts of carbon in the top and subsoil in both the mineral organic matter and particulate organic matter fractions. We also question nitrogen management in these systems.
Claude Raoul Müller, Johan Six, Daniel Mugendi Njiru, Bernard Vanlauwe, and Marijn Van de Broek
EGUsphere, https://doi.org/10.5194/egusphere-2024-2796, https://doi.org/10.5194/egusphere-2024-2796, 2024
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We studied how different organic and inorganic nutrient inputs affect soil organic carbon (SOC) down to 70 cm in Kenya. After 19 years, all organic treatments increased SOC stocks as compared to the control, but mineral nitrogen had no significant effect. Manure was the organic treatment that significantly increased SOC the deepest as its effect could be observed down to 60 cm. Manure was the best strategy to limit SOC loss in croplands and maintain soil quality after deforestation.
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
Biogeosciences, 21, 3691–3716, https://doi.org/10.5194/bg-21-3691-2024, https://doi.org/10.5194/bg-21-3691-2024, 2024
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We used the DayCent model to assess the potential impact of integrated soil fertility management (ISFM) on maize production, soil fertility, and greenhouse gas emission in Kenya. After adjustments, DayCent represented measured mean yields and soil carbon stock changes well and N2O emissions acceptably. Our results showed that soil fertility losses could be reduced but not completely eliminated with ISFM and that, while N2O emissions increased with ISFM, emissions per kilogram yield decreased.
Roxanne Daelman, Marijn Bauters, Matti Barthel, Emmanuel Bulonza, Lodewijk Lefevre, José Mbifo, Johan Six, Klaus Butterbach-Bahl, Benjamin Wolf, Ralf Kiese, and Pascal Boeckx
EGUsphere, https://doi.org/10.5194/egusphere-2024-2346, https://doi.org/10.5194/egusphere-2024-2346, 2024
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The increase in atmospheric concentrations of several greenhouse gasses (GHG) since 1750 is attributed to human activity, however natural ecosystems, such as tropical forests, also contribute to GHG budgets. The Congo basin hosts the second largest tropical forest and is understudied. In this study, measurements of soil GHG exchange were carried out during 16 months in a tropical forest in the Congo Basin. Overall, the soil acted as a major source for CO2 and N2O and a minor sink for CH4.
Marcel Bühler, Christoph Häni, Albrecht Neftel, Patrice Bühler, Christof Ammann, and Thomas Kupper
Atmos. Meas. Tech., 17, 4649–4658, https://doi.org/10.5194/amt-17-4649-2024, https://doi.org/10.5194/amt-17-4649-2024, 2024
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Methane was released from an artificial source inside a barn to test the applicability of the inverse dispersion method (IDM). Multiple open-path concentration devices and ultrasonic anemometers were used at the site. It is concluded that, for the present study case, the effect of a building and a tree in the main wind axis led to a systematic underestimation of the IDM-derived emission rate probably due to deviations in the wind field and turbulent dispersion from the ideal assumptions.
Marijn Van de Broek, Gerard Govers, Marion Schrumpf, and Johan Six
EGUsphere, https://doi.org/10.5194/egusphere-2024-2205, https://doi.org/10.5194/egusphere-2024-2205, 2024
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Soil organic carbon models are used to predict how soils affect the concentration of CO2 in the atmosphere. We show that equifinality – the phenomenon that different parameter values lead to correct overall model outputs, albeit with a different model behaviour – is an important source of model uncertainty. Our results imply that adding more complexity to soil organic carbon models is unlikely to lead to better predictions, as long as more data to constrain model parameters are not available.
Claude Raoul Müller, Johan Six, Liesa Brosens, Philipp Baumann, Jean Paolo Gomes Minella, Gerard Govers, and Marijn Van de Broek
SOIL, 10, 349–365, https://doi.org/10.5194/soil-10-349-2024, https://doi.org/10.5194/soil-10-349-2024, 2024
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Subsoils in the tropics are not as extensively studied as those in temperate regions. In this study, the conversion of forest to agriculture in a subtropical region affected the concentration of stabilized organic carbon (OC) down to 90 cm depth, while no significant differences between 90 cm and 300 cm were detected. Our results suggest that subsoils below 90 cm are unlikely to accumulate additional stabilized OC through reforestation over decadal periods due to declining OC input with depth.
Johan Six, Sebastian Doetterl, Moritz Laub, Claude R. Müller, and Marijn Van de Broek
SOIL, 10, 275–279, https://doi.org/10.5194/soil-10-275-2024, https://doi.org/10.5194/soil-10-275-2024, 2024
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Soil C saturation has been tested in several recent studies and led to a debate about its existence. We argue that, to test C saturation, one should pay attention to six fundamental principles: the right measures, the right units, the right dispersive energy and application, the right soil type, the right clay type, and the right saturation level. Once we take care of those six rights across studies, we find support for a maximum of C stabilized by minerals and thus soil C saturation.
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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Conservation agriculture (CA), combining reduced or no tillage, permanent soil cover, and improved rotations, is often promoted as a climate-smart practice. However, our knowledge of the impact of CA on top- and subsoil soil organic carbon (SOC) stocks in the low-input cropping systems of sub-Saharan Africa is rather limited. Using two long-term experimental sites with different soil types, we found that mulch could increase top SOC stocks, but no tillage alone had a slightly negative impact.
Mosisa Tujuba Wakjira, Nadav Peleg, Johan Six, and Peter Molnar
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2024-37, https://doi.org/10.5194/hess-2024-37, 2024
Revised manuscript under review for HESS
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While rainwater is a key resource in crop production, its productivity faces challenges from climate change. Using a simple model of climate, water, and crop yield interactions, we found that rain-scarce croplands in Ethiopia are likely to experience decreases in crop yield during the main growing season, primarily due to future temperature increases. These insights are crucial for shaping future water management plans, policies, and informed decision-making for climate adaptation.
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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To manage soil organic matter (SOM) sustainably, we need a better understanding of the role that soil microbes play in aggregate protection. Here, we propose the SAMM model, which connects soil aggregate formation to microbial growth. We tested it against data from a tropical long-term experiment and show that SAMM effectively represents the microbial growth, SOM, and aggregate dynamics and that it can be used to explore the importance of aggregate formation in SOM stabilization.
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.
Marsailidh M. Twigg, Augustinus J. C. Berkhout, Nicholas Cowan, Sabine Crunaire, Enrico Dammers, Volker Ebert, Vincent Gaudion, Marty Haaima, Christoph Häni, Lewis John, Matthew R. Jones, Bjorn Kamps, John Kentisbeer, Thomas Kupper, Sarah R. Leeson, Daiana Leuenberger, Nils O. B. Lüttschwager, Ulla Makkonen, Nicholas A. Martin, David Missler, Duncan Mounsor, Albrecht Neftel, Chad Nelson, Eiko Nemitz, Rutger Oudwater, Celine Pascale, Jean-Eudes Petit, Andrea Pogany, Nathalie Redon, Jörg Sintermann, Amy Stephens, Mark A. Sutton, Yuk S. Tang, Rens Zijlmans, Christine F. Braban, and Bernhard Niederhauser
Atmos. Meas. Tech., 15, 6755–6787, https://doi.org/10.5194/amt-15-6755-2022, https://doi.org/10.5194/amt-15-6755-2022, 2022
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Ammonia (NH3) gas in the atmosphere impacts the environment, human health, and, indirectly, climate. Historic NH3 monitoring was labour intensive, and the instruments were complicated. Over the last decade, there has been a rapid technology development, including “plug-and-play” instruments. This study is an extensive field comparison of the currently available technologies and provides evidence that for routine monitoring, standard operating protocols are required for datasets to be comparable.
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.
Brieuc Hardy, Nils Borchard, and Jens Leifeld
SOIL, 8, 451–466, https://doi.org/10.5194/soil-8-451-2022, https://doi.org/10.5194/soil-8-451-2022, 2022
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Soil amendment with artificial black carbon (BC; biomass transformed by incomplete combustion) has the potential to mitigate climate change. Nevertheless, the accurate quantification of BC in soil remains a critical issue. Here, we successfully used dynamic thermal analysis (DTA) to quantify centennial BC in soil. We demonstrate that DTA is largely under-exploited despite providing rapid and low-cost quantitative information over the range of soil organic matter.
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
Preprint withdrawn
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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.
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.
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.
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.
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.
Christoph Häni, Marcel Bühler, Albrecht Neftel, Christof Ammann, and Thomas Kupper
Atmos. Meas. Tech., 14, 1733–1741, https://doi.org/10.5194/amt-14-1733-2021, https://doi.org/10.5194/amt-14-1733-2021, 2021
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.
Long Ho, Ruben Jerves-Cobo, Matti Barthel, Johan Six, Samuel Bode, Pascal Boeckx, and Peter Goethals
Biogeosciences Discuss., https://doi.org/10.5194/bg-2020-311, https://doi.org/10.5194/bg-2020-311, 2020
Revised manuscript not accepted
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Rivers are being polluted by human activities, especially in urban areas. We studied the greenhouse gas (GHG) emissions from an urban river system. The results showed a clear trend between water quality and GHG emissions in which the more polluted the sites were, the higher were their emissions. When river water quality worsened, its contribution to global warming can go up by 10 times. Urban rivers emitted 4-times more than of the amount of GHGs compared to rivers in natural sites.
Miriam Groß-Schmölders, Pascal von Sengbusch, Jan Paul Krüger, Kristy Klein, Axel Birkholz, Jens Leifeld, and Christine Alewell
SOIL, 6, 299–313, https://doi.org/10.5194/soil-6-299-2020, https://doi.org/10.5194/soil-6-299-2020, 2020
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Degradation turns peatlands into a source of CO2. There is no cost- or time-efficient method available for indicating peatland hydrology or the success of restoration. We found that 15N values have a clear link to microbial communities and degradation. We identified trends in natural, drained and rewetted conditions and concluded that 15N depth profiles can act as a reliable and efficient tool for obtaining information on current hydrology, restoration success and drainage history.
Marijn Van de Broek, Shiva Ghiasi, Charlotte Decock, Andreas Hund, Samuel Abiven, Cordula Friedli, Roland A. Werner, and Johan Six
Biogeosciences, 17, 2971–2986, https://doi.org/10.5194/bg-17-2971-2020, https://doi.org/10.5194/bg-17-2971-2020, 2020
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Four wheat cultivars were labeled with 13CO2 to quantify the effect of rooting depth and root biomass on the belowground transfer of organic carbon. We found no clear relation between the time since cultivar development and the amount of carbon inputs to the soil. Therefore, the hypothesis that wheat cultivars with a larger root biomass and deeper roots promote carbon stabilization was rejected. The amount of root biomass that will be stabilized in the soil on the long term is, however, unknown.
Stephen J. Harris, Jesper Liisberg, Longlong Xia, Jing Wei, Kerstin Zeyer, Longfei Yu, Matti Barthel, Benjamin Wolf, Bryce F. J. Kelly, Dioni I. Cendón, Thomas Blunier, Johan Six, and Joachim Mohn
Atmos. Meas. Tech., 13, 2797–2831, https://doi.org/10.5194/amt-13-2797-2020, https://doi.org/10.5194/amt-13-2797-2020, 2020
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The latest commercial laser spectrometers have the potential to revolutionize N2O isotope analysis. However, to do so, they must be able to produce trustworthy data. Here, we test the performance of widely used laser spectrometers for ambient air applications and identify instrument-specific dependencies on gas matrix and trace gas concentrations. We then provide a calibration workflow to facilitate the operation of these instruments in order to generate reproducible and accurate data.
Chris R. Flechard, Andreas Ibrom, Ute M. Skiba, Wim de Vries, Marcel van Oijen, David R. Cameron, Nancy B. Dise, Janne F. J. Korhonen, Nina Buchmann, Arnaud Legout, David Simpson, Maria J. Sanz, Marc Aubinet, Denis Loustau, Leonardo Montagnani, Johan Neirynck, Ivan A. Janssens, Mari Pihlatie, Ralf Kiese, Jan Siemens, André-Jean Francez, Jürgen Augustin, Andrej Varlagin, Janusz Olejnik, Radosław Juszczak, Mika Aurela, Daniel Berveiller, Bogdan H. Chojnicki, Ulrich Dämmgen, Nicolas Delpierre, Vesna Djuricic, Julia Drewer, Eric Dufrêne, Werner Eugster, Yannick Fauvel, David Fowler, Arnoud Frumau, André Granier, Patrick Gross, Yannick Hamon, Carole Helfter, Arjan Hensen, László Horváth, Barbara Kitzler, Bart Kruijt, Werner L. Kutsch, Raquel Lobo-do-Vale, Annalea Lohila, Bernard Longdoz, Michal V. Marek, Giorgio Matteucci, Marta Mitosinkova, Virginie Moreaux, Albrecht Neftel, Jean-Marc Ourcival, Kim Pilegaard, Gabriel Pita, Francisco Sanz, Jan K. Schjoerring, Maria-Teresa Sebastià, Y. Sim Tang, Hilde Uggerud, Marek Urbaniak, Netty van Dijk, Timo Vesala, Sonja Vidic, Caroline Vincke, Tamás Weidinger, Sophie Zechmeister-Boltenstern, Klaus Butterbach-Bahl, Eiko Nemitz, and Mark A. Sutton
Biogeosciences, 17, 1583–1620, https://doi.org/10.5194/bg-17-1583-2020, https://doi.org/10.5194/bg-17-1583-2020, 2020
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Experimental evidence from a network of 40 monitoring sites in Europe suggests that atmospheric nitrogen deposition to forests and other semi-natural vegetation impacts the carbon sequestration rates in ecosystems, as well as the net greenhouse gas balance including other greenhouse gases such as nitrous oxide and methane. Excess nitrogen deposition in polluted areas also leads to other environmental impacts such as nitrogen leaching to groundwater and other pollutant gaseous emissions.
Chris R. Flechard, Marcel van Oijen, David R. Cameron, Wim de Vries, Andreas Ibrom, Nina Buchmann, Nancy B. Dise, Ivan A. Janssens, Johan Neirynck, Leonardo Montagnani, Andrej Varlagin, Denis Loustau, Arnaud Legout, Klaudia Ziemblińska, Marc Aubinet, Mika Aurela, Bogdan H. Chojnicki, Julia Drewer, Werner Eugster, André-Jean Francez, Radosław Juszczak, Barbara Kitzler, Werner L. Kutsch, Annalea Lohila, Bernard Longdoz, Giorgio Matteucci, Virginie Moreaux, Albrecht Neftel, Janusz Olejnik, Maria J. Sanz, Jan Siemens, Timo Vesala, Caroline Vincke, Eiko Nemitz, Sophie Zechmeister-Boltenstern, Klaus Butterbach-Bahl, Ute M. Skiba, and Mark A. Sutton
Biogeosciences, 17, 1621–1654, https://doi.org/10.5194/bg-17-1621-2020, https://doi.org/10.5194/bg-17-1621-2020, 2020
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Nitrogen deposition from the atmosphere to unfertilized terrestrial vegetation such as forests can increase carbon dioxide uptake and favour carbon sequestration by ecosystems. However the data from observational networks are difficult to interpret in terms of a carbon-to-nitrogen response, because there are a number of other confounding factors, such as climate, soil physical properties and fertility, and forest age. We propose a model-based method to untangle the different influences.
Karl Voglmeier, Johan Six, Markus Jocher, and Christof Ammann
Biogeosciences, 16, 1685–1703, https://doi.org/10.5194/bg-16-1685-2019, https://doi.org/10.5194/bg-16-1685-2019, 2019
Tino Colombi, Florian Walder, Lucie Büchi, Marlies Sommer, Kexing Liu, Johan Six, Marcel G. A. van der Heijden, Raphaël Charles, and Thomas Keller
SOIL, 5, 91–105, https://doi.org/10.5194/soil-5-91-2019, https://doi.org/10.5194/soil-5-91-2019, 2019
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The role of soil aeration in carbon sequestration in arable soils has only been explored little, especially at the farm level. The current study, which was conducted on 30 fields that belong to individual farms, reveals a positive relationship between soil gas transport capability and soil organic carbon content. We therefore conclude that soil aeration needs to be accounted for when developing strategies for carbon sequestration in arable soil.
Elizabeth Verhoeven, Matti Barthel, Longfei Yu, Luisella Celi, Daniel Said-Pullicino, Steven Sleutel, Dominika Lewicka-Szczebak, Johan Six, and Charlotte Decock
Biogeosciences, 16, 383–408, https://doi.org/10.5194/bg-16-383-2019, https://doi.org/10.5194/bg-16-383-2019, 2019
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This study utilized state-of-the-art measurements of nitrogen isotopes to evaluate nitrogen cycling and to assess the biological sources of the potent greenhouse gas, N2O, in response to water-saving practices in rice systems. Water-saving practices did emit more N2O, and high N2O production had a lower 15N isotope signature. Modeling and visual interpretation indicate that these emissions mostly came from denitrification or nitrifier denitrification, controlled upstream by nitrification rates.
Cédric Bader, Moritz Müller, Rainer Schulin, and Jens Leifeld
Biogeosciences, 15, 703–719, https://doi.org/10.5194/bg-15-703-2018, https://doi.org/10.5194/bg-15-703-2018, 2018
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When drained, peatlands degrade and release large quantities of CO2, thereby contributing to global warming. Do land use or the chemical composition of peat control the rate of that release? We studied 21 sites from the temperate climate zone managed as croplands, grasslands, or forests and found that the CO2 release was high, but only slightly influenced by land use or peat composition. Hence, only keeping peatlands in their natural state prevents them from becoming strong CO2 sources.
Michael Bell, Chris Flechard, Yannick Fauvel, Christoph Häni, Jörg Sintermann, Markus Jocher, Harald Menzi, Arjan Hensen, and Albrecht Neftel
Atmos. Meas. Tech., 10, 1875–1892, https://doi.org/10.5194/amt-10-1875-2017, https://doi.org/10.5194/amt-10-1875-2017, 2017
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This study applies horizontal concentration gradient measurements and inverse dispersion modelling to evaluate ammonia emissions from cattle grazing. The results can contribute to an emission factor for cattle grazing, where emissions where found to be towards the lower end of the range found in the limited number of existing studies. The influences of ammonia deposition, uneven urine patch distribution and climate conditions are discussed.
Jörg Sintermann, Klaus Dietrich, Christoph Häni, Michael Bell, Markus Jocher, and Albrecht Neftel
Atmos. Meas. Tech., 9, 2721–2734, https://doi.org/10.5194/amt-9-2721-2016, https://doi.org/10.5194/amt-9-2721-2016, 2016
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We present a DOAS instrument optimised for open-path field measurements of ambient ammonia (NH3) alongside nitrogen oxide (NO) and sulfur dioxide (SO2). We use a temperature-controlled spectrometer, a deuterium light source and a modified optical arrangement. The system was set up in a robust, field-deployable, temperature-regulated housing. For the evaluation of light spectra a new high-pass filter routine based upon robust baseline extraction with local regression was used.
Robert F. Grant, Albrecht Neftel, and Pierluigi Calanca
Biogeosciences, 13, 3549–3571, https://doi.org/10.5194/bg-13-3549-2016, https://doi.org/10.5194/bg-13-3549-2016, 2016
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The magnitude of N2O emissions from managed grasslands depends on weather and on harvesting and fertilizer practices. Modelling provides a means to predict these emissions under diverse weather and management types. In this modelling study, we show that N2O emissions depend on how weather affects temperatures and water contents of surface litter and near-surface soil. N2O emissions modelled from the grassland were increased by suboptimal harvesting practices, fertilizer timing and soil properties.
Lorenzo Menichetti, Thomas Kätterer, and Jens Leifeld
Biogeosciences, 13, 3003–3019, https://doi.org/10.5194/bg-13-3003-2016, https://doi.org/10.5194/bg-13-3003-2016, 2016
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Soil organic carbon dynamics are crucial for the global greenhouse gas balance, but their complexity is difficult to model and understand. We therefore often rely on radiocarbon measurements for calibrating models, but their effect on our understanding of the processes is still unclear. We calibrated five model structures on data from a long-term Swiss field experiment in a Bayesian framework to assess the effect of radiocarbon on the parameter and structural uncertainty of a soil carbon model.
Raphael Felber, Daniel Bretscher, Andreas Münger, Albrecht Neftel, and Christof Ammann
Biogeosciences, 13, 2959–2969, https://doi.org/10.5194/bg-13-2959-2016, https://doi.org/10.5194/bg-13-2959-2016, 2016
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We compare the carbon budget of a pasture using two different system boundaries: including and excluding grazing cows. We reveal the importance of non-CO2 fluxes as budget components depending on the chosen system boundaries and discuss the effect of their uncertainties. Budget components were directly measured or derived from cow related measured parameters like milk yield. The resulting carbon budgets of both approaches agree within the limits of uncertainty showing a near-neutral behavior.
C. Decock, J. Lee, M. Necpalova, E. I. P. Pereira, D. M. Tendall, and J. Six
SOIL, 1, 687–694, https://doi.org/10.5194/soil-1-687-2015, https://doi.org/10.5194/soil-1-687-2015, 2015
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Further progress in understanding and mitigating N2O emissions from soil lies within transdisciplinary research that reaches across spatial scales and takes an ambitious look into the future.
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
J. Leifeld and J. Mayer
SOIL, 1, 537–542, https://doi.org/10.5194/soil-1-537-2015, https://doi.org/10.5194/soil-1-537-2015, 2015
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We present 14C data for field replicates of a controlled agricultural long-term experiment. We show that 14C variability is, on average, 12 times that of the analytical precision of the 14C measurement. Experimental 14C variability is related to neither management nor soil depth. Application of a simple carbon turnover model reveals that experimental variability of radiocarbon results in higher absolute uncertainties of estimated carbon turnover time for deeper soil layers.
G. Wohlfahrt, C. Amelynck, C. Ammann, A. Arneth, I. Bamberger, A. H. Goldstein, L. Gu, A. Guenther, A. Hansel, B. Heinesch, T. Holst, L. Hörtnagl, T. Karl, Q. Laffineur, A. Neftel, K. McKinney, J. W. Munger, S. G. Pallardy, G. W. Schade, R. Seco, and N. Schoon
Atmos. Chem. Phys., 15, 7413–7427, https://doi.org/10.5194/acp-15-7413-2015, https://doi.org/10.5194/acp-15-7413-2015, 2015
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Methanol is the second most abundant volatile organic compound in the troposphere and plays a significant role in atmospheric chemistry. While there is consensus about the dominant role of plants as the major source and the reaction with OH as the major sink, global methanol budgets diverge considerably in terms of source/sink estimates. Here we present micrometeorological methanol flux data from eight sites in order to provide a first cross-site synthesis of the terrestrial methanol exchange.
R. Felber, A. Münger, A. Neftel, and C. Ammann
Biogeosciences, 12, 3925–3940, https://doi.org/10.5194/bg-12-3925-2015, https://doi.org/10.5194/bg-12-3925-2015, 2015
J. Sintermann and A. Neftel
Biogeosciences, 12, 3225–3240, https://doi.org/10.5194/bg-12-3225-2015, https://doi.org/10.5194/bg-12-3225-2015, 2015
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In this article we summarise recent science, which shows how airborne amines, specifically methylamines (MAs), play a key role in atmospheric new particle formation (NPF) by stabilising small molecule clusters. Agricultural emissions are assumed to constitute the most important MA source, but given the short atmospheric residence time of MAs, they can hardly have a direct impact on NFP events observed in remote regions. This leads us to the presentation of existing knowledge focussing on natural
J. P. Krüger, J. Leifeld, S. Glatzel, S. Szidat, and C. Alewell
Biogeosciences, 12, 2861–2871, https://doi.org/10.5194/bg-12-2861-2015, https://doi.org/10.5194/bg-12-2861-2015, 2015
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Biogeochemical soil parameters are studied to detect peatland degradation along a land use gradient (intensive, extensive, near-natural). Stable carbon isotopes, radiocarbon ages and ash content confirm peat growth in the near-natural bog but also indicate previous degradation. When the bog is managed extensively or intensively as grassland, all parameters indicate degradation and substantial C loss of the order of 18.8 to 42.9 kg C m-2.
B. Wolf, L. Merbold, C. Decock, B. Tuzson, E. Harris, J. Six, L. Emmenegger, and J. Mohn
Biogeosciences, 12, 2517–2531, https://doi.org/10.5194/bg-12-2517-2015, https://doi.org/10.5194/bg-12-2517-2015, 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.
E. C. Brevik, A. Cerdà, J. Mataix-Solera, L. Pereg, J. N. Quinton, J. Six, and K. Van Oost
SOIL, 1, 117–129, https://doi.org/10.5194/soil-1-117-2015, https://doi.org/10.5194/soil-1-117-2015, 2015
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This paper provides a brief accounting of some of the many ways that the study of soils can be interdisciplinary, therefore giving examples of the types of papers we hope to see submitted to SOIL.
J. Sintermann, S. Schallhart, M. Kajos, M. Jocher, A. Bracher, A. Münger, D. Johnson, A. Neftel, and T. Ruuskanen
Biogeosciences, 11, 5073–5085, https://doi.org/10.5194/bg-11-5073-2014, https://doi.org/10.5194/bg-11-5073-2014, 2014
J. Leifeld, C. Bader, E. Borraz, M. Hoffmann, M. Giebels, M. Sommer, and J. Augustin
Biogeosciences Discuss., https://doi.org/10.5194/bgd-11-12341-2014, https://doi.org/10.5194/bgd-11-12341-2014, 2014
Revised manuscript not accepted
J. P. Krüger, J. Leifeld, and C. Alewell
Biogeosciences, 11, 3369–3380, https://doi.org/10.5194/bg-11-3369-2014, https://doi.org/10.5194/bg-11-3369-2014, 2014
Related subject area
Soils and biogeochemical cycling
Soil organic matter interactions along the elevation gradient of the James Ross Island (Antarctica)
Investigating the complementarity of thermal and physical soil organic carbon fractions
An ensemble estimate of Australian soil organic carbon using machine learning and process-based modelling
What is the stability of additional organic carbon stored thanks to alternative cropping systems and organic waste product application? A multi-method evaluation
Improving measurements of microbial growth, death, and turnover by accounting for extracellular DNA in soils
Freeze-thaw processes correspond to the protection-loss of soil organic carbon through regulating pore structure of aggregates in alpine ecosystems
The influence of land use and management on the behaviour and persistence of soil organic carbon in a subtropical Ferralsol
Dissolved carbon flow to particulate organic carbon enhances soil carbon sequestration
Effect of colloidal particle size on physicochemical properties and aggregation behaviors of two alkaline soils
Depth-dependence of soil organic carbon additional storage capacity in different soil types by the 2050 target for carbon neutrality
Mixed signals: interpreting mixing patterns of different soil bioturbation processes through luminescence and numerical modelling
Shifts in controls and abundance of particulate and mineral-associated organic matter fractions among subfield yield stability zones
The six rights of how and when to test for soil C saturation
Comprehensive increase in CO2 release by drying-rewetting cycles among Japanese forests and pastureland soils and exploring predictors of increasing magnitude
Interactions of fertilisation and crop productivity on soil nitrogen cycle microbiome and gas emissions
Cover crops improve soil structure and change organic carbon distribution in macroaggregate fractions
Soil carbon, nitrogen, and phosphorus storage in juniper–oak savanna: role of vegetation and geology
Organic matters, but inorganic matters too: column examination of elevated mercury sorption on low organic matter aquifer material using concentrations and stable isotope ratios
Soil organic carbon mineralization is controlled by the application dose of exogenous organic matter
Contrasting potential for biological N2 fixation at three polluted central European Sphagnum peat bogs: combining the 15N2-tracer and natural-abundance isotope approaches
Soil organic carbon stocks did not change after 130 years of afforestation on a former Swiss Alpine pasture
Land inclination controls CO2 and N2O fluxes, but not CH4 uptake, in a temperate upland forest soil
Tropical Andosol organic carbon quality and degradability in relation to soil geochemistry as affected by land use
Elemental stoichiometry and Rock-Eval® thermal stability of organic matter in French topsoils
Oil-palm management alters the spatial distribution of amorphous silica and mobile silicon in topsoils
Semantics about soil organic carbon storage: DATA4C+, a comprehensive thesaurus and classification of management practices in agriculture and forestry
Forest liming in the face of climate change: the implications of restorative liming for soil organic carbon in mature German forests
Biotic factors dominantly determine soil inorganic carbon stock across Tibetan alpine grasslands
Effects of returning corn straw and fermented corn straw to fields on the soil organic carbon pools and humus composition
Soil nutrient contents and stoichiometry within aggregate size classes varied with tea plantation age and soil depth in southern Guangxi in China
Land use impact on carbon mineralization in well aerated soils is mainly explained by variations of particulate organic matter rather than of soil structure
Inclusion of biochar in a C dynamics model based on observations from an 8-year field experiment
Synergy between compost and cover crops in a Mediterranean row crop system leads to increased subsoil carbon storage
Phosphorus dynamics during early soil development in a cold desert: insights from oxygen isotopes in phosphate
Transformation of n-alkanes from plant to soil: a review
Heterotrophic soil respiration and carbon cycling in geochemically distinct African tropical forest soils
Soil organic carbon mobility in equatorial podzols: soil column experiments
Microbial activity responses to water stress in agricultural soils from simple and complex crop rotations
The role of geochemistry in organic carbon stabilization against microbial decomposition in tropical rainforest soils
Geogenic organic carbon in terrestrial sediments and its contribution to total soil carbon
Aluminous clay and pedogenic Fe oxides modulate aggregation and related carbon contents in soils of the humid tropics
Continental-scale controls on soil organic carbon across sub-Saharan Africa
Modelling of long-term Zn, Cu, Cd and Pb dynamics from soils fertilised with organic amendments
Stable isotope signatures of soil nitrogen on an environmental–geomorphic gradient within the Congo Basin
Iron and aluminum association with microbially processed organic matter via meso-density aggregate formation across soils: organo-metallic glue hypothesis
Land-use perturbations in ley grassland decouple the degradation of ancient soil organic matter from the storage of newly derived carbon inputs
Switch of fungal to bacterial degradation in natural, drained and rewetted oligotrophic peatlands reflected in δ15N and fatty acid composition
Catchment export of base cations: improved mineral dissolution kinetics influence the role of water transit time
Boreal-forest soil chemistry drives soil organic carbon bioreactivity along a 314-year fire chronosequence
Ramped thermal analysis for isolating biologically meaningful soil organic matter fractions with distinct residence times
Vítězslav Vlček, David Juřička, Martin Valtera, Helena Dvořáčková, Vojtěch Štulc, Michaela Bednaříková, Jana Šimečková, Peter Váczi, Miroslav Pohanka, Pavel Kapler, Miloš Barták, and Vojtěch Enev
SOIL, 10, 813–826, https://doi.org/10.5194/soil-10-813-2024, https://doi.org/10.5194/soil-10-813-2024, 2024
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The aim of this work was to evaluate the correlation between soil organic carbon (SOC) and various soil properties. Nine plots across an altitudinal range from 10 to 320 m were investigated in the deglaciated region of James Ross Island (Antarctica). Our results indicate that the primary factor influencing the SOC content is likely not altitude or coarse-fraction content; rather, other hard-to-quantify factors, such as the presence of liquid water during the summer period, impact SOC content.
Amicie A. Delahaie, Lauric Cécillon, Marija Stojanova, Samuel Abiven, Pierre Arbelet, Dominique Arrouays, François Baudin, Antonio Bispo, Line Boulonne, Claire Chenu, Jussi Heinonsalo, Claudy Jolivet, Kristiina Karhu, Manuel Martin, Lorenza Pacini, Christopher Poeplau, Céline Ratié, Pierre Roudier, Nicolas P. A. Saby, Florence Savignac, and Pierre Barré
SOIL, 10, 795–812, https://doi.org/10.5194/soil-10-795-2024, https://doi.org/10.5194/soil-10-795-2024, 2024
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This paper compares the soil organic carbon fractions obtained from a new thermal fractionation scheme and a well-known physical fractionation scheme on an unprecedented dataset of French topsoil samples. For each fraction, we use a machine learning model to determine its environmental drivers (pedology, climate, and land cover). Our results suggest that these two fractionation schemes provide different fractions, which means they provide complementary information.
Lingfei Wang, Gab Abramowitz, Ying-Ping Wang, Andy Pitman, and Raphael A. Viscarra Rossel
SOIL, 10, 619–636, https://doi.org/10.5194/soil-10-619-2024, https://doi.org/10.5194/soil-10-619-2024, 2024
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Effective management of soil organic carbon (SOC) requires accurate knowledge of its distribution and factors influencing its dynamics. We identify the importance of variables in spatial SOC variation and estimate SOC stocks in Australia using various models. We find there are significant disparities in SOC estimates when different models are used, highlighting the need for a critical re-evaluation of land management strategies that rely on the SOC distribution derived from a single approach.
Tchodjowiè P. I. Kpemoua, Pierre Barré, Sabine Houot, François Baudin, Cédric Plessis, and Claire Chenu
SOIL, 10, 533–549, https://doi.org/10.5194/soil-10-533-2024, https://doi.org/10.5194/soil-10-533-2024, 2024
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Several agroecological management options foster soil organic C stock accrual. What is behind the persistence of this "additional" C? We used three different methodological approaches and >20 years of field experiments under temperate conditions to find out. We found that the additional C is less stable at the pluri-decadal scale than the baseline C. This highlights the need to maintain agroecological practices to keep these carbon stocks at a high level over time.
Jörg Schnecker, Theresa Böckle, Julia Horak, Victoria Martin, Taru Sandén, and Heide Spiegel
SOIL, 10, 521–531, https://doi.org/10.5194/soil-10-521-2024, https://doi.org/10.5194/soil-10-521-2024, 2024
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Microbial processes are driving the formation and decomposition of soil organic matter. In contrast to respiration and growth, microbial death rates currently lack distinct methods to be determined. Here, we propose a new approach to measure microbial death rates. This new approach to determine microbial death rates as well as dynamics of intracellular and extracellular DNA separately will help to improve concepts and models of C dynamics in soils in the future.
Ruizhe Wang and Xia Hu
EGUsphere, https://doi.org/10.5194/egusphere-2024-1833, https://doi.org/10.5194/egusphere-2024-1833, 2024
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In this paper, we studied the impact of seasonal freeze-thaw processes on pore structure and SOC fraction contents of aggregates in typical alpine ecosystems in the Qinghai Lake basin. We sampled soils in four freeze-thaw periods and pore structure was quantified using X-ray compyuted tomography. Also, we revealed that the freezing and thawing corresponded to the protection and loss for SOC of aggregates, respectively, through regulating pore structure.
Laura Hondroudakis, Peter M. Kopittke, Ram C. Dalal, Meghan Barnard, and Zhe H. Weng
SOIL, 10, 451–465, https://doi.org/10.5194/soil-10-451-2024, https://doi.org/10.5194/soil-10-451-2024, 2024
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Land use change to cropping is known to greatly reduced organic carbon and nitrogen concentrations, but much remains unknown about the mechanisms influencing their persistence in soil. In a soil from a subtropical Australian cropping system, we demonstrate that organic carbon is protected by mineral associations but not particulate forms. Importantly, we also show that reversion from cropping to pasture or plantation can partially restore this organic carbon.
Qintana Si, Kangli Chen, Bin Wei, Yaowen Zhang, Xun Sun, and Junyi Liang
SOIL, 10, 441–450, https://doi.org/10.5194/soil-10-441-2024, https://doi.org/10.5194/soil-10-441-2024, 2024
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Our soil incubation experiment demonstrates that dissolved labile carbon substrate is a significant contributor to the soil particulate organic carbon pool. Dissolved carbon flow to particulate organic carbon is regulated by microbial biomass carbon and soil texture. The soil carbon model underestimates soil carbon sequestration when carbon flow from dissolved substrates to particulate organic carbon through microbial processes is not considered.
Yuyang Yan, Xinran Zhang, Chenyang Xu, Junjun Liu, Feinan Hu, and Zengchao Geng
EGUsphere, https://doi.org/10.5194/egusphere-2024-1266, https://doi.org/10.5194/egusphere-2024-1266, 2024
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With decreasing colloidal particle diameter, the total carbon content, organic carbon, organic functional groups content and illite content all increased. The critical coagulation concentrations (CCCs) values of soil colloids followed the descending order of d < 100 nm, d < 1 μm, d < 2 μm, thus soil nanoparticles exhibited strongest suspension stability.
Clémentine Chirol, Geoffroy Séré, Paul-Olivier Redon, Claire Chenu, and Delphine Derrien
EGUsphere, https://doi.org/10.5194/egusphere-2024-1284, https://doi.org/10.5194/egusphere-2024-1284, 2024
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This work maps both current soil organic carbon (SOC) stocks and the SOC that can be realistically added to soils over 25 years under a scenario of management strategies promoting plant productivity. We consider how soil type influences current and maximum SOC stocks regionally. Over 25 years, land use and management have the strongest influence on SOC accrual, but certain soil types have disproportionate SOC stocks at depth that need to be preserved.
W. Marijn van der Meij, Svenja Riedesel, and Tony Reimann
EGUsphere, https://doi.org/10.5194/egusphere-2024-1466, https://doi.org/10.5194/egusphere-2024-1466, 2024
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Soil mixing (bioturbation) plays a key role in soil functions, but the underlying processes are poorly understood and difficult to quantify. In this study, we use luminescence, a light-sensitive soil mineral property, and numerical models to better understand different types of bioturbation. We provide a conceptual model that helps to determine what type of bioturbation processes occur in a soil and a numerical model that can derive quantitative process rates from luminescence measurements.
Sam J. Leuthold, Jocelyn M. Lavallee, Bruno Basso, William F. Brinton, and M. Francesca Cotrufo
SOIL, 10, 307–319, https://doi.org/10.5194/soil-10-307-2024, https://doi.org/10.5194/soil-10-307-2024, 2024
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We examined physical soil organic matter fractions to understand their relationship to temporal variability in crop yield at field scale. We found that interactions between crop productivity, topography, and climate led to variability in soil organic matter stocks among different yield stability zones. Our results imply that linkages between soil organic matter and yield stability may be scale-dependent and that particulate organic matter may be an indicator of unstable areas within croplands.
Johan Six, Sebastian Doetterl, Moritz Laub, Claude R. Müller, and Marijn Van de Broek
SOIL, 10, 275–279, https://doi.org/10.5194/soil-10-275-2024, https://doi.org/10.5194/soil-10-275-2024, 2024
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Soil C saturation has been tested in several recent studies and led to a debate about its existence. We argue that, to test C saturation, one should pay attention to six fundamental principles: the right measures, the right units, the right dispersive energy and application, the right soil type, the right clay type, and the right saturation level. Once we take care of those six rights across studies, we find support for a maximum of C stabilized by minerals and thus soil C saturation.
Yuri Suzuki, Syuntaro Hiradate, Jun Koarashi, Mariko Atarashi-Andoh, Takumi Yomogida, Yuki Kanda, and Hirohiko Nagano
EGUsphere, https://doi.org/10.5194/egusphere-2024-419, https://doi.org/10.5194/egusphere-2024-419, 2024
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We incubated 10 Japanese soils to study CO2 release under drying-rewetting cycles (DWCs). CO2 release was increased by DWCs among all soils, showing soil-by-soil variations in CO2 release increase magnitude. Organo-Al complex was the primary predictor for the increase magnitude, suggesting vulnerability of carbon protection by reactive minerals against DWCs. Microbial biomass decrease by DWCs was also suggested, although its linkage with the CO2 release increase is unclear yet.
Laura Kuusemets, Ülo Mander, Jordi Escuer-Gatius, Alar Astover, Karin Kauer, Kaido Soosaar, and Mikk Espenberg
EGUsphere, https://doi.org/10.5194/egusphere-2024-593, https://doi.org/10.5194/egusphere-2024-593, 2024
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We investigated relationships between mineral nitrogen (N) fertilisation rates and additional manure amendment with different crop types through the analysis of soil environmental characteristics and microbiome, soil N2O and N2 emissions, and biomass production. Results show that wheat was growing well at a fertilisation rate of 80 kg N ha−1, and newly introduced sorghum showed good potential for cultivation in temperate climate.
Norman Gentsch, Florin Laura Riechers, Jens Boy, Dörte Schweneker, Ulf Feuerstein, Diana Heuermann, and Georg Guggenberger
SOIL, 10, 139–150, https://doi.org/10.5194/soil-10-139-2024, https://doi.org/10.5194/soil-10-139-2024, 2024
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Cover crops have substantial impacts on soil properties, but so far it is not clear how long a legacy effect of cover cropping will remain in the soil. We found that cover crops attenuate negative effects on soil structure that come from soil cultivation. The combination of plants with different litter qualities and rhizodeposits in biodiverse cover crop mixtures can improve the positive effects of cover cropping on soil structure amelioration.
Che-Jen Hsiao, Pedro A. M. Leite, Ayumi Hyodo, and Thomas W. Boutton
SOIL, 10, 93–108, https://doi.org/10.5194/soil-10-93-2024, https://doi.org/10.5194/soil-10-93-2024, 2024
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Tree cover has increased in grasslands worldwide, with juniper and oak trees expanding in the southern Great Plains, USA. Here, we examine how these changes interact with geology to affect soil C, N, and P storage. Soil concentrations of these elements were significantly higher under trees than grasslands but increased more under trees growing on Edwards soils. Our results suggest that geology and vegetation change should be considered when predicting soil storage in dryland ecosystems globally.
David S. McLagan, Carina Esser, Lorenz Schwab, Jan G. Wiederhold, Jan-Helge Richard, and Harald Biester
SOIL, 10, 77–92, https://doi.org/10.5194/soil-10-77-2024, https://doi.org/10.5194/soil-10-77-2024, 2024
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Sorption of mercury in soils, aquifer materials, and sediments is primarily linked to organic matter. Using column experiments, mercury concentration, speciation, and stable isotope analyses, we show that large quantities of mercury in soil water and groundwater can be sorbed to inorganic minerals; sorption to the solid phase favours lighter isotopes. Data provide important insights on the transport and fate of mercury in soil–groundwater systems and particularly in low-organic-matter systems.
Orly Mendoza, Stefaan De Neve, Heleen Deroo, Haichao Li, Astrid Françoys, and Steven Sleutel
EGUsphere, https://doi.org/10.5194/egusphere-2024-107, https://doi.org/10.5194/egusphere-2024-107, 2024
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Farmers frequently apply fresh organic matter such as crop residues to soil to boost its carbon content. Yet, one burning question remains: Does the quantity of applied organic matter affect its decomposition and that of native soil organic matter? Our experiments indicate that smaller application doses might deplete soil organic matter more rapidly. In contrast, applying intermediate or high doses might be a promising strategy for maintaining it.
Marketa Stepanova, Martin Novak, Bohuslava Cejkova, Ivana Jackova, Frantisek Buzek, Frantisek Veselovsky, Jan Curik, Eva Prechova, Arnost Komarek, and Leona Bohdalkova
SOIL, 9, 623–640, https://doi.org/10.5194/soil-9-623-2023, https://doi.org/10.5194/soil-9-623-2023, 2023
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Biological N2 fixation helps to sustain carbon accumulation in peatlands and to remove CO2 from the atmosphere. Changes in N2 fixation may affect the dynamics of global change. Increasing inputs of reactive N from air pollution should lead to downregulation of N2 fixation. Data from three N-polluted peat bogs show an interplay of N2-fixation rates with 10 potential drivers of this process. N2 fixation was measurable only at one site characterized by high phosphorus and low sulfate availability.
Tatjana C. Speckert, Jeannine Suremann, Konstantin Gavazov, Maria J. Santos, Frank Hagedorn, and Guido L. B. Wiesenberg
SOIL, 9, 609–621, https://doi.org/10.5194/soil-9-609-2023, https://doi.org/10.5194/soil-9-609-2023, 2023
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Soil organic carbon (SOC) is key player in the global carbon cycle. Afforestation on pastures potentially alters organic matter input and SOC sequestration. We investigated the effects of a Picea abies L. afforestation sequence (0 to 130 years) on a former subalpine pasture on SOC stocks and dynamics. We found no difference in the SOC stock after 130 years of afforestation and thus no additional SOC sequestration. SOC composition was altered due to a modified SOC input following afforestation.
Lauren M. Gillespie, Nathalie Y. Triches, Diego Abalos, Peter Finke, Sophie Zechmeister-Boltenstern, Stephan Glatzel, and Eugenio Díaz-Pinés
SOIL, 9, 517–531, https://doi.org/10.5194/soil-9-517-2023, https://doi.org/10.5194/soil-9-517-2023, 2023
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Forest soil is potentially an important source or sink of greenhouse gases (CO2, N2O, and CH4), but this is affected by soil conditions. We studied how land inclination and soil/litter properties influence the flux of these gases. CO2 and N2O were more affected by inclination than CH4; all were affected by soil/litter properties. This study underlines the importance of inclination and soil/litter properties in predicting greenhouse gas fluxes from forest soil and potential source–sink balance.
Sastrika Anindita, Peter Finke, and Steven Sleutel
SOIL, 9, 443–459, https://doi.org/10.5194/soil-9-443-2023, https://doi.org/10.5194/soil-9-443-2023, 2023
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This study investigated how land use, through its impact on soil geochemistry, might indirectly control soil organic carbon (SOC) content in tropical volcanic soils in Indonesia. We analyzed SOC fractions, substrate-specific mineralization, and net priming of SOC. Our results indicated that the enhanced formation of aluminum (hydr)oxides promoted aggregation and physical occlusion of OC, which is consistent with the lesser degradability of SOC in agricultural soils.
Amicie A. Delahaie, Pierre Barré, François Baudin, Dominique Arrouays, Antonio Bispo, Line Boulonne, Claire Chenu, Claudy Jolivet, Manuel P. Martin, Céline Ratié, Nicolas P. A. Saby, Florence Savignac, and Lauric Cécillon
SOIL, 9, 209–229, https://doi.org/10.5194/soil-9-209-2023, https://doi.org/10.5194/soil-9-209-2023, 2023
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We characterized organic matter in French soils by analysing samples from the French RMQS network using Rock-Eval thermal analysis. We found that thermal analysis is appropriate to characterize large set of samples (ca. 2000) and provides interpretation references for Rock-Eval parameter values. This shows that organic matter in managed soils is on average more oxidized and more thermally stable and that some Rock-Eval parameters are good proxies for organic matter biogeochemical stability.
Britta Greenshields, Barbara von der Lühe, Harold J. Hughes, Christian Stiegler, Suria Tarigan, Aiyen Tjoa, and Daniela Sauer
SOIL, 9, 169–188, https://doi.org/10.5194/soil-9-169-2023, https://doi.org/10.5194/soil-9-169-2023, 2023
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Silicon (Si) research could provide complementary measures in sustainably cultivating oil-palm monocultures. Our study shows that current oil-palm management practices and topsoil erosion on oil-palm plantations in Indonesia have caused a spatial distribution of essential Si pools in soil. A lack of well-balanced Si levels in topsoil could negatively affect crop yield and soil fertility for future replanting at the same plantation site. Potential measures are suggested to maintain Si cycling.
Kenji Fujisaki, Tiphaine Chevallier, Antonio Bispo, Jean-Baptiste Laurent, François Thevenin, Lydie Chapuis-Lardy, Rémi Cardinael, Christine Le Bas, Vincent Freycon, Fabrice Bénédet, Vincent Blanfort, Michel Brossard, Marie Tella, and Julien Demenois
SOIL, 9, 89–100, https://doi.org/10.5194/soil-9-89-2023, https://doi.org/10.5194/soil-9-89-2023, 2023
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This paper presents a first comprehensive thesaurus for management practices driving soil organic carbon (SOC) storage. So far, a comprehensive thesaurus of management practices in agriculture and forestry has been lacking. It will help to merge datasets, a promising way to evaluate the impacts of management practices in agriculture and forestry on SOC. Identifying the drivers of SOC stock changes is of utmost importance to contribute to global challenges (climate change, food security).
Oliver van Straaten, Larissa Kulp, Guntars O. Martinson, Dan Paul Zederer, and Ulrike Talkner
SOIL, 9, 39–54, https://doi.org/10.5194/soil-9-39-2023, https://doi.org/10.5194/soil-9-39-2023, 2023
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Across northern Europe, millions of hectares of forest have been limed to counteract soil acidification and restore forest ecosystems. In this study, we investigated how restorative liming affects the forest soil organic carbon (SOC) stocks and correspondingly ecosystem greenhouse gas fluxes. We found that the magnitude and direction of SOC stock changes hinge on the inherent site characteristics, namely, forest type, soil texture, initial soil pH, and initial soil SOC stocks (before liming).
Junxiao Pan, Jinsong Wang, Dashuan Tian, Ruiyang Zhang, Yang Li, Lei Song, Jiaming Yang, Chunxue Wei, and Shuli Niu
SOIL, 8, 687–698, https://doi.org/10.5194/soil-8-687-2022, https://doi.org/10.5194/soil-8-687-2022, 2022
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We found that climatic, edaphic, plant and microbial variables jointly affect soil inorganic carbon (SIC) stock in Tibetan grasslands, and biotic factors have a larger contribution than abiotic factors to the variation in SIC stock. The effects of microbial and plant variables on SIC stock weakened with soil depth, while the effects of edaphic variables strengthened. The contrasting responses and drivers of SIC stock highlight differential mechanisms underlying SIC preservation with soil depth.
Yifeng Zhang, Sen Dou, Batande Sinovuyo Ndzelu, Rui Ma, Dandan Zhang, Xiaowei Zhang, Shufen Ye, and Hongrui Wang
SOIL, 8, 605–619, https://doi.org/10.5194/soil-8-605-2022, https://doi.org/10.5194/soil-8-605-2022, 2022
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How to effectively convert corn straw into humic substances and return them to the soil in a relatively stable form is a concerning topic. Through a 360 d field experiment under equal carbon (C) mass, we found that return of the fermented corn straw treated with Trichoderma reesei to the field is more valuable and conducive to increasing easily oxidizable organic C, humus C content, and carbon pool management index than the direct application of corn straw.
Ling Mao, Shaoming Ye, and Shengqiang Wang
SOIL, 8, 487–505, https://doi.org/10.5194/soil-8-487-2022, https://doi.org/10.5194/soil-8-487-2022, 2022
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Soil ecological stoichiometry offers a tool to explore the distribution, cycling, limitation, and balance of chemical elements. This study improved the understanding of soil organic carbon and nutrient dynamics in tea plantation ecosystems and also provided supplementary information for soil ecological stoichiometry in global terrestrial ecosystems.
Steffen Schlüter, Tim Roussety, Lena Rohe, Vusal Guliyev, Evgenia Blagodatskaya, and Thomas Reitz
SOIL, 8, 253–267, https://doi.org/10.5194/soil-8-253-2022, https://doi.org/10.5194/soil-8-253-2022, 2022
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We combined microstructure analysis via X-ray CT with carbon mineralization analysis via respirometry of intact soil cores from different land uses. We found that the amount of particulate organic matter (POM) exerted a dominant control on carbon mineralization in well-aerated topsoils, whereas soil moisture and macroporosity did not play role. This is because carbon mineralization mainly occurs in microbial hotspots around degrading POM, where it is decoupled from conditions of the bulk soil.
Roberta Pulcher, Enrico Balugani, Maurizio Ventura, Nicolas Greggio, and Diego Marazza
SOIL, 8, 199–211, https://doi.org/10.5194/soil-8-199-2022, https://doi.org/10.5194/soil-8-199-2022, 2022
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Biochar, a solid product from the thermal conversion of biomass, can be used as a climate change mitigation strategy, since it can sequester carbon from the atmosphere and store it in the soil. The aim of this study is to assess the potential of biochar as a mitigation strategy in the long term, by modelling the results obtained from an 8-year field experiment. As far as we know, this is the first time that a model for biochar degradation has been validated with long-term field data.
Daniel Rath, Nathaniel Bogie, Leonardo Deiss, Sanjai J. Parikh, Daoyuan Wang, Samantha Ying, Nicole Tautges, Asmeret Asefaw Berhe, Teamrat A. Ghezzehei, and Kate M. Scow
SOIL, 8, 59–83, https://doi.org/10.5194/soil-8-59-2022, https://doi.org/10.5194/soil-8-59-2022, 2022
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Storing C in subsoils can help mitigate climate change, but this requires a better understanding of subsoil C dynamics. We investigated changes in subsoil C storage under a combination of compost, cover crops (WCC), and mineral fertilizer and found that systems with compost + WCC had ~19 Mg/ha more C after 25 years. This increase was attributed to increased transport of soluble C and nutrients via WCC root pores and demonstrates the potential for subsoil C storage in tilled agricultural systems.
Zuzana Frkova, Chiara Pistocchi, Yuliya Vystavna, Katerina Capkova, Jiri Dolezal, and Federica Tamburini
SOIL, 8, 1–15, https://doi.org/10.5194/soil-8-1-2022, https://doi.org/10.5194/soil-8-1-2022, 2022
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Phosphorus (P) is essential for life. We studied microbial processes driving the P cycle in soils developed on the same rock but with different ages (0–100 years) in a cold desert. Compared to previous studies under cold climate, we found much slower weathering of P-containing minerals of soil development, likely due to aridity. However, microbes dominate short-term dynamics and progressively redistribute P from the rock into more available forms, making it available for plants at later stages.
Carrie L. Thomas, Boris Jansen, E. Emiel van Loon, and Guido L. B. Wiesenberg
SOIL, 7, 785–809, https://doi.org/10.5194/soil-7-785-2021, https://doi.org/10.5194/soil-7-785-2021, 2021
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Plant organs, such as leaves, contain a variety of chemicals that are eventually deposited into soil and can be useful for studying organic carbon cycling. We performed a systematic review of available data of one type of plant-derived chemical, n-alkanes, to determine patterns of degradation or preservation from the source plant to the soil. We found that while there was degradation in the amount of n-alkanes from plant to soil, some aspects of the chemical signature were preserved.
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.
Patricia Merdy, Yves Lucas, Bruno Coulomb, Adolpho J. Melfi, and Célia R. Montes
SOIL, 7, 585–594, https://doi.org/10.5194/soil-7-585-2021, https://doi.org/10.5194/soil-7-585-2021, 2021
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Transfer of organic C from topsoil to deeper horizons and the water table is little documented, especially in equatorial environments, despite high primary productivity in the evergreen forest. Using column experiments with podzol soil and a percolating solution sampled in an Amazonian podzol area, we show how the C-rich Bh horizon plays a role in natural organic matter transfer and Si, Fe and Al mobility after a kaolinitic layer transition, thus giving insight to the genesis of tropical podzol.
Jörg Schnecker, D. Boone Meeden, Francisco Calderon, Michel Cavigelli, R. Michael Lehman, Lisa K. Tiemann, and A. Stuart Grandy
SOIL, 7, 547–561, https://doi.org/10.5194/soil-7-547-2021, https://doi.org/10.5194/soil-7-547-2021, 2021
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Drought and flooding challenge agricultural systems and their management globally. Here we investigated the response of soils from long-term agricultural field sites with simple and diverse crop rotations to either drought or flooding. We found that irrespective of crop rotation complexity, soil and microbial properties were more resistant to flooding than to drought and highly resilient to drought and flooding during single or repeated stress pulses.
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.
Fabian Kalks, Gabriel Noren, Carsten W. Mueller, Mirjam Helfrich, Janet Rethemeyer, and Axel Don
SOIL, 7, 347–362, https://doi.org/10.5194/soil-7-347-2021, https://doi.org/10.5194/soil-7-347-2021, 2021
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Sedimentary rocks contain organic carbon that may end up as soil carbon. However, this source of soil carbon is overlooked and has not been quantified sufficiently. We analysed 10 m long sediment cores with three different sedimentary rocks. All sediments contain considerable amounts of geogenic carbon contributing 3 %–12 % to the total soil carbon below 30 cm depth. The low 14C content of geogenic carbon can result in underestimations of soil carbon turnover derived from 14C data.
Maximilian Kirsten, Robert Mikutta, Didas N. Kimaro, Karl-Heinz Feger, and Karsten Kalbitz
SOIL, 7, 363–375, https://doi.org/10.5194/soil-7-363-2021, https://doi.org/10.5194/soil-7-363-2021, 2021
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Mineralogical combinations of aluminous clay and pedogenic Fe oxides revealed significant effects on soil structure and related organic carbon (OC) storage.
The mineralogical combination resulting in the largest aggregate stability does not better preserve OC during conversion of forests into croplands.
Structural changes in the direction of smaller mean weight diameters do not cancel out the stabilizing effect of soil minerals.
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.
Claudia Cagnarini, Stephen Lofts, Luigi Paolo D'Acqui, Jochen Mayer, Roman Grüter, Susan Tandy, Rainer Schulin, Benjamin Costerousse, Simone Orlandini, and Giancarlo Renella
SOIL, 7, 107–123, https://doi.org/10.5194/soil-7-107-2021, https://doi.org/10.5194/soil-7-107-2021, 2021
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Application of organic amendments, although considered a sustainable form of soil fertilisation, may cause an accumulation of trace elements (TEs) in the topsoil. In this research, we analysed the concentration of zinc, copper, lead and cadmium in a > 60-year experiment in Switzerland and showed that the dynamic model IDMM adequately predicted the historical TE concentrations in plots amended with farmyard manure, sewage sludge and compost and produced reasonable concentration trends up to 2100.
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.
Rota Wagai, Masako Kajiura, and Maki Asano
SOIL, 6, 597–627, https://doi.org/10.5194/soil-6-597-2020, https://doi.org/10.5194/soil-6-597-2020, 2020
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Global significance of metals (extractable Fe and Al phases) to control organic matter (OM) in recognized. Next key questions include the identification of their localization and mechanism behind OM–metal relationships. Across 23 soils of contrasting mineralogy, Fe and Al phases were mainly associated with microbially processed OM as meso-density microaggregates. OM- and metal-rich nanocomposites with a narrow OM : metal ratio likely acted as binding agents. A new conceptual model was proposed.
Marco Panettieri, Denis Courtier-Murias, Cornelia Rumpel, Marie-France Dignac, Gonzalo Almendros, and Abad Chabbi
SOIL, 6, 435–451, https://doi.org/10.5194/soil-6-435-2020, https://doi.org/10.5194/soil-6-435-2020, 2020
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In the context of global change, soil has been identified as a potential C sink, depending on land-use strategies. This work is devoted to identifying the processes affecting labile soil C pools resulting from changes in land use. We show that the land-use change in ley grassland provoked a decoupling of the storage and degradation processes after the grassland phase. Overall, the study enables us to develop a sufficient understanding of fine-scale C dynamics to refine soil C prediction models.
Miriam Groß-Schmölders, Pascal von Sengbusch, Jan Paul Krüger, Kristy Klein, Axel Birkholz, Jens Leifeld, and Christine Alewell
SOIL, 6, 299–313, https://doi.org/10.5194/soil-6-299-2020, https://doi.org/10.5194/soil-6-299-2020, 2020
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Degradation turns peatlands into a source of CO2. There is no cost- or time-efficient method available for indicating peatland hydrology or the success of restoration. We found that 15N values have a clear link to microbial communities and degradation. We identified trends in natural, drained and rewetted conditions and concluded that 15N depth profiles can act as a reliable and efficient tool for obtaining information on current hydrology, restoration success and drainage history.
Martin Erlandsson Lampa, Harald U. Sverdrup, Kevin H. Bishop, Salim Belyazid, Ali Ameli, and Stephan J. Köhler
SOIL, 6, 231–244, https://doi.org/10.5194/soil-6-231-2020, https://doi.org/10.5194/soil-6-231-2020, 2020
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In this study, we demonstrate how new equations describing base cation release from mineral weathering can reproduce patterns in observations from stream and soil water. This is a major step towards modeling base cation cycling on the catchment scale, which would be valuable for defining the highest sustainable rates of forest harvest and levels of acidifying deposition.
Benjamin Andrieux, David Paré, Julien Beguin, Pierre Grondin, and Yves Bergeron
SOIL, 6, 195–213, https://doi.org/10.5194/soil-6-195-2020, https://doi.org/10.5194/soil-6-195-2020, 2020
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Our study aimed to disentangle the contribution of several drivers to explaining the proportion of soil carbon that can be released to CO2 through microbial respiration. We found that boreal-forest soil chemistry is an important driver of the amount of carbon that microbes can process. Our results emphasize the need to include the effects of soil chemistry into models of carbon cycling to better anticipate the role played by boreal-forest soils in carbon-cycle–climate feedbacks.
Jonathan Sanderman and A. Stuart Grandy
SOIL, 6, 131–144, https://doi.org/10.5194/soil-6-131-2020, https://doi.org/10.5194/soil-6-131-2020, 2020
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Soils contain one of the largest and most dynamic pools of carbon on Earth, yet scientists still struggle to understand the reactivity and fate of soil organic matter upon disturbance. In this study, we found that with increasing thermal stability, the turnover time of organic matter increased from decades to centuries with a concurrent shift in chemical composition. In this proof-of-concept study, we found that ramped thermal analyses can provide new insights for understanding soil carbon.
Cited articles
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Angst, T. E., Six, J., Reay, D. S., and Sohi, S. P.: Impact of pine chip biochar on trace greenhouse gas emissions and soil nutrient dynamics in an annual ryegrass system in California, Agr. Ecosyst. Environ., 191, 17–26, https://doi.org/10.1016/j.agee.2014.03.009, 2014.
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Short summary
Biochar is considered an opportunity to tackle major environmental issues in agriculture. Adding pyrolised organic residues to soil may sequester carbon, increase yields and reduce nitrous oxide emissions from soil. It is unknown, whether the latter is induced by changes in soil pH. We show that biochar application substantially reduces nitrous oxide emissions from a temperate maize cropping system. However, the reduction was only achieved with biochar but not with liming.
Biochar is considered an opportunity to tackle major environmental issues in agriculture. Adding...