Articles | Volume 10, issue 1
https://doi.org/10.5194/soil-10-23-2024
© Author(s) 2024. 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-10-23-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Forum article
| 
15 Jan 2024
Forum article |
| 15 Jan 2024
| 15 Jan 2024
Perspectives on the misconception of levitating soil aggregates
Department of Agroecology and Environment, Agroscope, Reckenholzstrasse 191, 8046 Zurich, Switzerland
Department of Environmental Systems Science, Swiss Federal Institute of Technology – ETH Zurich, Universitätstrasse 16, 8092 Zurich, Switzerland
John Koestel
Department of Agroecology and Environment, Agroscope, Reckenholzstrasse 191, 8046 Zurich, Switzerland
Department of Soil and Environment, Swedish University of Agricultural Sciences, P.O. Box 7014, 75007 Uppsala, Sweden
Alice Johannes
Department of Agroecology and Environment, Agroscope, Reckenholzstrasse 191, 8046 Zurich, Switzerland
Olivier Heller
Department of Agroecology and Environment, Agroscope, Reckenholzstrasse 191, 8046 Zurich, Switzerland
Sebastian Doetterl
Department of Environmental Systems Science, Swiss Federal Institute of Technology – ETH Zurich, Universitätstrasse 16, 8092 Zurich, Switzerland
Department of Environmental Systems Science, Swiss Federal Institute of Technology – ETH Zurich, Universitätstrasse 16, 8092 Zurich, Switzerland
Division of Hydrologic Sciences, Desert Research Institute, 2215 Raggio Parkway, Reno, NV 89512, USA
Thomas Keller
Department of Agroecology and Environment, Agroscope, Reckenholzstrasse 191, 8046 Zurich, Switzerland
Department of Soil and Environment, Swedish University of Agricultural Sciences, P.O. Box 7014, 75007 Uppsala, Sweden
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Hydrol. Earth Syst. Sci., 28, 3391–3433, https://doi.org/10.5194/hess-28-3391-2024, https://doi.org/10.5194/hess-28-3391-2024, 2024
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Pedotransfer functions (PTFs) are used to predict parameters of models describing the hydraulic properties of soils. The appropriateness of these predictions critically relies on the nature of the datasets for training the PTFs and the physical comprehensiveness of the models. This roadmap paper is addressed to PTF developers and users and critically reflects the utility and future of PTFs. To this end, we present a manifesto aiming at a paradigm shift in PTF research.
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.
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.
Guillaume Blanchy, Lukas Albrecht, Gilberto Bragato, Sarah Garré, Nicholas Jarvis, and John Koestel
Hydrol. Earth Syst. Sci., 27, 2703–2724, https://doi.org/10.5194/hess-27-2703-2023, https://doi.org/10.5194/hess-27-2703-2023, 2023
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We collated the Open Tension-disk Infiltrometer Meta-database (OTIM). We analysed topsoil hydraulic conductivities at supply tensions between 0 and 100 mm of 466 data entries. We found indications of different flow mechanisms at saturation and at tensions >20 mm. Climate factors were better correlated with near-saturated hydraulic conductivities than soil properties. Land use, tillage system, soil compaction and experimenter bias significantly influenced K to a similar degree to soil properties.
Guillaume Blanchy, Lukas Albrecht, John Koestel, and Sarah Garré
SOIL, 9, 155–168, https://doi.org/10.5194/soil-9-155-2023, https://doi.org/10.5194/soil-9-155-2023, 2023
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Benjamin Bukombe, Peter Fiener, Alison M. Hoyt, Laurent K. Kidinda, and Sebastian Doetterl
SOIL, 7, 639–659, https://doi.org/10.5194/soil-7-639-2021, https://doi.org/10.5194/soil-7-639-2021, 2021
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Through a laboratory incubation experiment, we investigated the spatial patterns of specific maximum heterotrophic respiration in tropical African mountain forest soils developed from contrasting parent material along slope gradients. We found distinct differences in soil respiration between soil depths and geochemical regions related to soil fertility and the chemistry of the soil solution. The topographic origin of our samples was not a major determinant of the observed rates of respiration.
Sebastian Doetterl, Rodrigue K. Asifiwe, Geert Baert, Fernando Bamba, Marijn Bauters, Pascal Boeckx, Benjamin Bukombe, Georg Cadisch, Matthew Cooper, Landry N. Cizungu, Alison Hoyt, Clovis Kabaseke, Karsten Kalbitz, Laurent Kidinda, Annina Maier, Moritz Mainka, Julia Mayrock, Daniel Muhindo, Basile B. Mujinya, Serge M. Mukotanyi, Leon Nabahungu, Mario Reichenbach, Boris Rewald, Johan Six, Anna Stegmann, Laura Summerauer, Robin Unseld, Bernard Vanlauwe, Kristof Van Oost, Kris Verheyen, Cordula Vogel, Florian Wilken, and Peter Fiener
Earth Syst. Sci. Data, 13, 4133–4153, https://doi.org/10.5194/essd-13-4133-2021, https://doi.org/10.5194/essd-13-4133-2021, 2021
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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.
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.
Surya Gupta, Tomislav Hengl, Peter Lehmann, Sara Bonetti, and Dani Or
Earth Syst. Sci. Data, 13, 1593–1612, https://doi.org/10.5194/essd-13-1593-2021, https://doi.org/10.5194/essd-13-1593-2021, 2021
Mengyuan Mu, Martin G. De Kauwe, Anna M. Ukkola, Andy J. Pitman, Teresa E. Gimeno, Belinda E. Medlyn, Dani Or, Jinyan Yang, and David S. Ellsworth
Hydrol. Earth Syst. Sci., 25, 447–471, https://doi.org/10.5194/hess-25-447-2021, https://doi.org/10.5194/hess-25-447-2021, 2021
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Land surface model (LSM) is a critical tool to study land responses to droughts and heatwaves, but lacking comprehensive observations limited past model evaluations. Here we use a novel dataset at a water-limited site, evaluate a typical LSM with a range of competing model hypotheses widely used in LSMs and identify marked uncertainty due to the differing process assumptions. We show the extensive observations constrain model processes and allow better simulated land responses to these extremes.
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
Preprint withdrawn
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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.
Katharina Hildegard Elisabeth Meurer, Claire Chenu, Elsa Coucheney, Anke Marianne Herrmann, Thomas Keller, Thomas Kätterer, David Nimblad Svensson, and Nicholas Jarvis
Biogeosciences, 17, 5025–5042, https://doi.org/10.5194/bg-17-5025-2020, https://doi.org/10.5194/bg-17-5025-2020, 2020
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We present a simple model that describes, for the first time, the dynamic two-way interactions between soil organic matter and soil physical properties (porosity, pore size distribution, bulk density and layer thickness). The model was able to accurately reproduce the changes in soil organic carbon, soil bulk density and surface elevation observed during 63 years in a field trial, as well as soil water retention curves measured at the end of the experimental period.
Arjun Chakrawal, Anke M. Herrmann, John Koestel, Jerker Jarsjö, Naoise Nunan, Thomas Kätterer, and Stefano Manzoni
Geosci. Model Dev., 13, 1399–1429, https://doi.org/10.5194/gmd-13-1399-2020, https://doi.org/10.5194/gmd-13-1399-2020, 2020
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Soils are heterogeneous, which results in a nonuniform spatial distribution of substrates and the microorganisms feeding on them. Our results show that the variability in the spatial distribution of substrates and microorganisms at the pore scale is crucial because it affects how fast substrates are used by microorganisms and thus the decomposition rate observed at the soil core scale. This work provides a methodology to include microscale heterogeneity in soil carbon cycling models.
Marco Pfeiffer, José Padarian, Rodrigo Osorio, Nelson Bustamante, Guillermo Federico Olmedo, Mario Guevara, Felipe Aburto, Francisco Albornoz, Monica Antilén, Elías Araya, Eduardo Arellano, Maialen Barret, Juan Barrera, Pascal Boeckx, Margarita Briceño, Sally Bunning, Lea Cabrol, Manuel Casanova, Pablo Cornejo, Fabio Corradini, Gustavo Curaqueo, Sebastian Doetterl, Paola Duran, Mauricio Escudey, Angelina Espinoza, Samuel Francke, Juan Pablo Fuentes, Marcel Fuentes, Gonzalo Gajardo, Rafael García, Audrey Gallaud, Mauricio Galleguillos, Andrés Gomez, Marcela Hidalgo, Jorge Ivelic-Sáez, Lwando Mashalaba, Francisco Matus, Francisco Meza, Maria de la Luz Mora, Jorge Mora, Cristina Muñoz, Pablo Norambuena, Carolina Olivera, Carlos Ovalle, Marcelo Panichini, Aníbal Pauchard, Jorge F. Pérez-Quezada, Sergio Radic, José Ramirez, Nicolás Riveras, Germán Ruiz, Osvaldo Salazar, Iván Salgado, Oscar Seguel, Maria Sepúlveda, Carlos Sierra, Yasna Tapia, Francisco Tapia, Balfredo Toledo, José Miguel Torrico, Susana Valle, Ronald Vargas, Michael Wolff, and Erick Zagal
Earth Syst. Sci. Data, 12, 457–468, https://doi.org/10.5194/essd-12-457-2020, https://doi.org/10.5194/essd-12-457-2020, 2020
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The CHLSOC database is the biggest soil organic carbon (SOC) database that has been compiled for Chile yet, comprising 13 612 data points. This database is the product of the compilation of numerous sources including unpublished and difficult-to-access data, allowing us to fill numerous spatial gaps where no SOC estimates were publicly available before. The values of SOC compiled in CHLSOC have a wide range, reflecting the variety of ecosystems that exists in Chile.
Corey R. Lawrence, Jeffrey Beem-Miller, Alison M. Hoyt, Grey Monroe, Carlos A. Sierra, Shane Stoner, Katherine Heckman, Joseph C. Blankinship, Susan E. Crow, Gavin McNicol, Susan Trumbore, Paul A. Levine, Olga Vindušková, Katherine Todd-Brown, Craig Rasmussen, Caitlin E. Hicks Pries, Christina Schädel, Karis McFarlane, Sebastian Doetterl, Christine Hatté, Yujie He, Claire Treat, Jennifer W. Harden, Margaret S. Torn, Cristian Estop-Aragonés, Asmeret Asefaw Berhe, Marco Keiluweit, Ágatha Della Rosa Kuhnen, Erika Marin-Spiotta, Alain F. Plante, Aaron Thompson, Zheng Shi, Joshua P. Schimel, Lydia J. S. Vaughn, Sophie F. von Fromm, and Rota Wagai
Earth Syst. Sci. Data, 12, 61–76, https://doi.org/10.5194/essd-12-61-2020, https://doi.org/10.5194/essd-12-61-2020, 2020
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The International Soil Radiocarbon Database (ISRaD) is an an open-source archive of soil data focused on datasets including radiocarbon measurements. ISRaD includes data from bulk or
whole soils, distinct soil carbon pools isolated in the laboratory by a variety of soil fractionation methods, samples of soil gas or water collected interstitially from within an intact soil profile, CO2 gas isolated from laboratory soil incubations, and fluxes collected in situ from a soil surface.
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.
Milad Aminzadeh, Peter Lehmann, and Dani Or
Hydrol. Earth Syst. Sci., 22, 4015–4032, https://doi.org/10.5194/hess-22-4015-2018, https://doi.org/10.5194/hess-22-4015-2018, 2018
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Significant evaporative losses from local water reservoirs in arid regions exacerbate water shortages during dry spells. We propose a systematic approach for modeling energy balance and fluxes from covered water bodies using self-assembling floating elements, considering cover properties and local conditions. The study will provide a scientific and generalized basis for designing and implementing this important water conservation strategy to assist with its adaptation in various arid regions.
Minsu Kim and Dani Or
Biogeosciences, 14, 5403–5424, https://doi.org/10.5194/bg-14-5403-2017, https://doi.org/10.5194/bg-14-5403-2017, 2017
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We report a mechanistic model for linking biophysical and chemical processes in Cyanobacterial crusts comprised of trophically interacting photoautotrophs, aerobic and anaerobic heterotrophs, and nitrifiers. The biocrust model captures salient aspects of microbial activity and community organisation in response to diurnal cycles of light and temperature. The framework offers new mechanistic insights into a host of highly dynamic and spatially resolved processes shaping biogeochemical fluxes.
Hannes Keck, Bjarne W. Strobel, Jon Petter Gustafsson, and John Koestel
SOIL, 3, 177–189, https://doi.org/10.5194/soil-3-177-2017, https://doi.org/10.5194/soil-3-177-2017, 2017
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Several studies have shown that the cation adsorption sites in soils are heterogeneously distributed in space. In many soil system models this knowledge is not included yet. In our study we proposed a new method to map the 3-D distribution of cation adsorption sites in undisturbed soils. The method is based on three-dimensional X-ray scanning with a contrast agent and image analysis. We are convinced that this approach will strongly aid the development of more realistic soil system models.
Stanislaus J. Schymanski, Daniel Breitenstein, and Dani Or
Hydrol. Earth Syst. Sci., 21, 3377–3400, https://doi.org/10.5194/hess-21-3377-2017, https://doi.org/10.5194/hess-21-3377-2017, 2017
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Leaf transpiration and energy exchange are coupled processes at the small scale that have strong effects on the water cycle and climate at the large scale. In this technical note, we present a novel experimental set-up that enables detailed study of these coupled processes in the laboratory under controlled conditions. Results document the abilities of the experimental set-up to confirm or challenge our understanding of these processes.
Stanislaus J. Schymanski and Dani Or
Hydrol. Earth Syst. Sci., 21, 685–706, https://doi.org/10.5194/hess-21-685-2017, https://doi.org/10.5194/hess-21-685-2017, 2017
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Most of the rain falling on land is returned to the atmosphere by plant leaves, which release water vapour (transpire) through tiny pores. To better understand this process, we used artificial leaves in a special wind tunnel and discovered major problems with an established approach (PM equation) widely used to quantify transpiration and its sensitivity to climate change. We present an improved set of equations, consistent with experiments and displaying more realistic climate sensitivity.
S. J. Schymanski and D. Or
Proc. IAHS, 371, 99–107, https://doi.org/10.5194/piahs-371-99-2015, https://doi.org/10.5194/piahs-371-99-2015, 2015
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The common use of "potential evaporation" to estimate actual evapotranspiration or to describe the suitability of a given climate for plant growth may lead to wrong conclusions about the consequences of climate change on plant growth and water relations. Wind speed in particular can have opposite effects on potential evaporation and transpiration from plant leaves. Therefore, we recommend to avoid using the concept of potential evaporation in relation to plants and transpiration from leaves.
M. Stähli, M. Sättele, C. Huggel, B. W. McArdell, P. Lehmann, A. Van Herwijnen, A. Berne, M. Schleiss, A. Ferrari, A. Kos, D. Or, and S. M. Springman
Nat. Hazards Earth Syst. Sci., 15, 905–917, https://doi.org/10.5194/nhess-15-905-2015, https://doi.org/10.5194/nhess-15-905-2015, 2015
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This review paper describes the state of the art in monitoring and predicting rapid mass movements for early warning. It further presents recent innovations in observation technologies and modelling to be used in future early warning systems (EWS). Finally, the paper proposes avenues towards successful implementation of next-generation EWS.
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.
M. Larsbo, J. Koestel, and N. Jarvis
Hydrol. Earth Syst. Sci., 18, 5255–5269, https://doi.org/10.5194/hess-18-5255-2014, https://doi.org/10.5194/hess-18-5255-2014, 2014
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The characteristics of the macropore network determine the potential for fast transport of solutes through soil. Such characteristics computed from 3-dimensional X-ray tomography images were combined with measured solute breakthrough curves and near-saturated hydraulic conductivities. At a given flow rate, smaller macroporosities, poorer local connectivity of the macropore network and smaller near-saturated hydraulic conductivities resulted in a greater degree of preferential transport.
Related subject area
Soils and water
High-resolution near-surface electromagnetic mapping for the hydrological modeling of an orange orchard
Mapping near-real-time soil moisture dynamics over Tasmania with transfer learning
The effect of groundwater depth on topsoil organic matter mineralization during a simulated dry summer in northwestern Europe
Depth extrapolation of field-scale soil moisture time series derived with cosmic-ray neutron sensing (CRNS) using the soil moisture analytical relationship (SMAR) model
Addressing soil data needs and data gaps in catchment-scale environmental modelling: the European perspective
Optimized fertilization using online soil nitrate data
Intensive agricultural management-induced subsurface accumulation of water-extractable colloidal P in a Vertisol
Combining lime and organic amendments based on titratable alkalinity for efficient amelioration of acidic soils
Sequestering carbon in the subsoil benefits crop transpiration at the onset of drought
Pesticide transport through the vadose zone under sugarcane in the Wet Tropics, Australia
Reproducibility of the wet part of the soil water retention curve: a European interlaboratory comparison
The higher relative concentration of K+ to Na+ in saline water improves soil hydraulic conductivity, salt-leaching efficiency and structural stability
Agricultural use of compost under different irrigation strategies in a hedgerow olive grove under Mediterranean conditions – a comparison with traditional systems
Potential of natural language processing for metadata extraction from environmental scientific publications
Soil and crop management practices and the water regulation functions of soils: a qualitative synthesis of meta-analyses relevant to European agriculture
Effects of innovative long-term soil and crop management on topsoil properties of a Mediterranean soil based on detailed water retention curves
Polyester microplastic fibers affect soil physical properties and erosion as a function of soil type
Modelling the effect of catena position and hydrology on soil chemical weathering
Long-term impact of cover crop and reduced disturbance tillage on soil pore size distribution and soil water storage
Effective hydraulic properties of 3D virtual stony soils identified by inverse modeling
Biochar alters hydraulic conductivity and impacts nutrient leaching in two agricultural soils
Impact of freeze–thaw cycles on soil structure and soil hydraulic properties
Added value of geophysics-based soil mapping in agro-ecosystem simulations
Particulate macronutrient exports from tropical African montane catchments point to the impoverishment of agricultural soils
A review of the global soil property maps for Earth system models
Saturated and unsaturated salt transport in peat from a constructed fen
Sensitivity analysis of point and parametric pedotransfer functions for estimating water retention of soils in Algeria
Water in the critical zone: soil, water and life from profile to planet
Deriving pedotransfer functions for soil quartz fraction in southern France from reverse modeling
Morphological dynamics of gully systems in the subhumid Ethiopian Highlands: the Debre Mawi watershed
Characterization of stony soils' hydraulic conductivity using laboratory and numerical experiments
Quantification of the impact of hydrology on agricultural production as a result of too dry, too wet or too saline conditions
Sediment concentration rating curves for a monsoonal climate: upper Blue Nile
Nonstationarity of the electrical resistivity and soil moisture relationship in a heterogeneous soil system: a case study
Interactions between organisms and parent materials of a constructed Technosol shape its hydrostructural properties
Potential effects of vinasse as a soil amendment to control runoff and soil loss
Quantification of the inevitable: the influence of soil macrofauna on soil water movement in rehabilitated open-cut mined lands
Coupled cellular automata for frozen soil processes
Luca Peruzzo, Ulrike Werban, Marco Pohle, Mirko Pavoni, Benjamin Mary, Giorgio Cassiani, Simona Consoli, and Daniela Vanella
EGUsphere, https://doi.org/10.5194/egusphere-2025-2117, https://doi.org/10.5194/egusphere-2025-2117, 2025
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Both spatial and temporal information are important in agriculture. Information regarding the above-ground variables ever-increasing in density and precision. On the contrary, below-ground information lags behind and has been typically limited to time series. This study uses methods that map the subsurface spatial variability. A numerical simulations of above- and below water fluxes are then based on such spatial information and additional time-oriented datasets that are common in agriculture.
Marliana Tri Widyastuti, José Padarian, Budiman Minasny, Mathew Webb, Muh Taufik, and Darren Kidd
SOIL, 11, 287–307, https://doi.org/10.5194/soil-11-287-2025, https://doi.org/10.5194/soil-11-287-2025, 2025
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This work aims to predict soil water content at a fine spatiotemporal resolution (80 m grids, daily) to support agricultural management in Tasmania. It proves that transfer learning can improve the accuracy of deep learning models to predict multilevel soil moisture. We address the challenge of mapping soil moisture at field-scale resolution and integrate the model into a near-real-time monitoring system.
Astrid Françoys, Orly Mendoza, Junwei Hu, Pascal Boeckx, Wim Cornelis, Stefaan De Neve, and Steven Sleutel
SOIL, 11, 121–140, https://doi.org/10.5194/soil-11-121-2025, https://doi.org/10.5194/soil-11-121-2025, 2025
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To assess the impact of the groundwater table (GWT) depth on soil moisture and C mineralization, we designed a laboratory setup using 200 cm undisturbed soil columns. Surprisingly, the moisture increase induced by a shallower GWT did not result in enhanced C mineralization. We presume this upward capillary moisture effect was offset by increased C mineralization upon rewetting, particularly noticeable in drier soils when capillary rise affected the topsoil to a lesser extent due to a deeper GWT.
Daniel Rasche, Theresa Blume, and Andreas Güntner
SOIL, 10, 655–677, https://doi.org/10.5194/soil-10-655-2024, https://doi.org/10.5194/soil-10-655-2024, 2024
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Soil moisture measurements at the field scale are highly beneficial for numerous (soil) hydrological applications. Cosmic-ray neutron sensing (CRNS) allows for the non-invasive monitoring of field-scale soil moisture across several hectares but only for the first few tens of centimetres of the soil. In this study, we modify and test a simple modeling approach to extrapolate CRNS-derived surface soil moisture information down to 450 cm depth and compare calibrated and uncalibrated model results.
Brigitta Szabó, Piroska Kassai, Svajunas Plunge, Attila Nemes, Péter Braun, Michael Strauch, Felix Witing, János Mészáros, and Natalja Čerkasova
SOIL, 10, 587–617, https://doi.org/10.5194/soil-10-587-2024, https://doi.org/10.5194/soil-10-587-2024, 2024
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This research introduces methods and tools for obtaining soil input data in European case studies for environmental models like SWAT+. With various available soil datasets and prediction methods, determining the most suitable is challenging. The study aims to (i) catalogue open-access datasets and prediction methods for Europe, (ii) demonstrate and quantify differences between prediction approaches, and (iii) offer a comprehensive workflow with open-source R codes for deriving missing soil data.
Yonatan Yekutiel, Yuval Rotem, Shlomi Arnon, and Ofer Dahan
SOIL, 10, 335–347, https://doi.org/10.5194/soil-10-335-2024, https://doi.org/10.5194/soil-10-335-2024, 2024
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A new soil nitrate monitoring system that was installed in a cultivated field enabled us, for the first-time, to control nitrate concentration across the soil profile. Frequent adjustment of fertilizer and water application followed the actual dynamic variation in nitrate concentration across the soil profile. Hence, a significant reduction in fertilizer application was achieved while preserving optimal crop yield.
Shouhao Li, Shuiqing Chen, Shanshan Bai, Jinfang Tan, and Xiaoqian Jiang
SOIL, 10, 49–59, https://doi.org/10.5194/soil-10-49-2024, https://doi.org/10.5194/soil-10-49-2024, 2024
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The distribution of water-extractable colloids with soil profiles of 0–120 cm was investigated in a Vertisol under high-intensity agricultural management. A large number of experimental data show that colloidal phosphorus plays an important role in apatite transport throughout the profile. Thus, it is crucial to consider the impact of colloidal P when predicting surface-to-subsurface P loss in Vertisols.
Birhanu Iticha, Luke M. Mosley, and Petra Marschner
SOIL, 10, 33–47, https://doi.org/10.5194/soil-10-33-2024, https://doi.org/10.5194/soil-10-33-2024, 2024
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Little effort has been made to develop methods to calculate the application rates of lime combined with organic amendments (OAs) needed to neutralise soil acidity and achieve the desired pH for plant growth. The previous approach of estimating appropriate lime and OA combinations based on field trials is time-consuming and costly. Hence, we developed and successfully validated a new method to calculate the amount of lime or OAs in combined applications required to ameliorate acidity.
Maria Eliza Turek, Attila Nemes, and Annelie Holzkämper
SOIL, 9, 545–560, https://doi.org/10.5194/soil-9-545-2023, https://doi.org/10.5194/soil-9-545-2023, 2023
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In this study, we systematically evaluated prospective crop transpiration benefits of sequestering soil organic carbon (SOC) under current and future climatic conditions based on the model SWAP. We found that adding at least 2% SOC down to at least 65 cm depth could increase transpiration annually by almost 40 mm, which can play a role in mitigating drought impacts in rain-fed cropping. Beyond this threshold, additional crop transpiration benefits of sequestering SOC are only marginal.
Rezaul Karim, Lucy Reading, Les Dawes, Ofer Dahan, and Glynis Orr
SOIL, 9, 381–398, https://doi.org/10.5194/soil-9-381-2023, https://doi.org/10.5194/soil-9-381-2023, 2023
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The study was performed using continuous measurement of temporal variations in soil saturation and of the concentration of pesticides along the vadose zone profile and underlying alluvial aquifers at sugarcane fields in the Wet Tropics of Australia. A vadose zone monitoring system was set up to enable the characterization of pesticide (non-PS II herbicides) migration with respect to pesticide application, sugarcane growing period, and, finally, rainwater infiltration.
Benjamin Guillaume, Hanane Aroui Boukbida, Gerben Bakker, Andrzej Bieganowski, Yves Brostaux, Wim Cornelis, Wolfgang Durner, Christian Hartmann, Bo V. Iversen, Mathieu Javaux, Joachim Ingwersen, Krzysztof Lamorski, Axel Lamparter, András Makó, Ana María Mingot Soriano, Ingmar Messing, Attila Nemes, Alexandre Pomes-Bordedebat, Martine van der Ploeg, Tobias Karl David Weber, Lutz Weihermüller, Joost Wellens, and Aurore Degré
SOIL, 9, 365–379, https://doi.org/10.5194/soil-9-365-2023, https://doi.org/10.5194/soil-9-365-2023, 2023
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Measurements of soil water retention properties play an important role in a variety of societal issues that depend on soil water conditions. However, there is little concern about the consistency of these measurements between laboratories. We conducted an interlaboratory comparison to assess the reproducibility of the measurement of the soil water retention curve. Results highlight the need to harmonize and standardize procedures to improve the description of unsaturated processes in soils.
Sihui Yan, Tibin Zhang, Binbin Zhang, Tonggang Zhang, Yu Cheng, Chun Wang, Min Luo, Hao Feng, and Kadambot H. M. Siddique
SOIL, 9, 339–349, https://doi.org/10.5194/soil-9-339-2023, https://doi.org/10.5194/soil-9-339-2023, 2023
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The paper provides some new information about the effects of different relative concentrations of K+ to Na+ at constant electrical conductivity (EC) on soil hydraulic conductivity, salt-leaching efficiency and pore size distribution. In addition to Ca2+ and Mg2+, K+ plays an important role in soil structure stability. These findings can provide a scientific basis and technical support for the sustainable use of saline water and control of soil quality deterioration.
Laura L. de Sosa, María José Martín-Palomo, Pedro Castro-Valdecantos, and Engracia Madejón
SOIL, 9, 325–338, https://doi.org/10.5194/soil-9-325-2023, https://doi.org/10.5194/soil-9-325-2023, 2023
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Olive groves are subject to enormous pressure to meet the social demands of production. In this work, we assess how an additional source of organic carbon and an irrigation control can somehow palliate the effect of olive grove intensification by comparing olive groves under different management and tree densities. We observed that a reduced irrigation regimen in combination with compost from the oil industry's own waste was able to enhance soil fertility under a water conservation strategy.
Guillaume Blanchy, Lukas Albrecht, John Koestel, and Sarah Garré
SOIL, 9, 155–168, https://doi.org/10.5194/soil-9-155-2023, https://doi.org/10.5194/soil-9-155-2023, 2023
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Adapting agricultural practices to future climatic conditions requires us to synthesize the effects of management practices on soil properties with respect to local soil and climate. We showcase different automated text-processing methods to identify topics, extract metadata for building a database and summarize findings from publication abstracts. While human intervention remains essential, these methods show great potential to support evidence synthesis from large numbers of publications.
Guillaume Blanchy, Gilberto Bragato, Claudia Di Bene, Nicholas Jarvis, Mats Larsbo, Katharina Meurer, and Sarah Garré
SOIL, 9, 1–20, https://doi.org/10.5194/soil-9-1-2023, https://doi.org/10.5194/soil-9-1-2023, 2023
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European agriculture is vulnerable to weather extremes. Nevertheless, by choosing well how to manage their land, farmers can protect themselves against drought and peak rains. More than a thousand observations across Europe show that it is important to keep the soil covered with living plants, even in winter. A focus on a general reduction of traffic on agricultural land is more important than reducing tillage. Organic material needs to remain or be added on the field as much as possible.
Alaitz Aldaz-Lusarreta, Rafael Giménez, Miguel A. Campo-Bescós, Luis M. Arregui, and Iñigo Virto
SOIL, 8, 655–671, https://doi.org/10.5194/soil-8-655-2022, https://doi.org/10.5194/soil-8-655-2022, 2022
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This study shows how an innovative soil and crop management including no-tillage, cover crops and organic amendments is able to improve the topsoil physical quality compared to conventional management for rainfed cereal cropping in a semi-arid Mediterranean area in Navarre (Spain).
Rosolino Ingraffia, Gaetano Amato, Vincenzo Bagarello, Francesco G. Carollo, Dario Giambalvo, Massimo Iovino, Anika Lehmann, Matthias C. Rillig, and Alfonso S. Frenda
SOIL, 8, 421–435, https://doi.org/10.5194/soil-8-421-2022, https://doi.org/10.5194/soil-8-421-2022, 2022
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The presence of microplastics in soil environments has received increased attention, but little research exists on the effects on different soil types and soil water erosion. We performed two experiments on the effects of polyester microplastic fiber on soil properties, soil aggregation, and soil erosion in three agricultural soils. Results showed that polyester microplastic fibers affect the formation of new aggregates and soil erosion and that such effects are strongly dependent on soil type.
Vanesa García-Gamero, Tom Vanwalleghem, Adolfo Peña, Andrea Román-Sánchez, and Peter A. Finke
SOIL, 8, 319–335, https://doi.org/10.5194/soil-8-319-2022, https://doi.org/10.5194/soil-8-319-2022, 2022
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Short-scale soil variability has received much less attention than at the regional scale. The chemical depletion fraction (CDF), a proxy for chemical weathering, was measured and simulated with SoilGen along two opposite slopes in southern Spain. The results show that differences in CDF could not be explained by topography alone but by hydrological parameters. The model sensitivity test shows the maximum CDF value for intermediate precipitation has similar findings to other soil properties.
Samuel N. Araya, Jeffrey P. Mitchell, Jan W. Hopmans, and Teamrat A. Ghezzehei
SOIL, 8, 177–198, https://doi.org/10.5194/soil-8-177-2022, https://doi.org/10.5194/soil-8-177-2022, 2022
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We studied the long-term effects of no-till (NT) and winter cover cropping (CC) practices on soil hydraulic properties. We measured soil water retention and conductivity and also conducted numerical simulations to compare soil water storage abilities under the different systems. Soils under NT and CC practices had improved soil structure. Conservation agriculture practices showed marginal improvement with respect to infiltration rates and water storage.
Mahyar Naseri, Sascha C. Iden, and Wolfgang Durner
SOIL, 8, 99–112, https://doi.org/10.5194/soil-8-99-2022, https://doi.org/10.5194/soil-8-99-2022, 2022
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We simulated stony soils with low to high volumes of rock fragments in 3D using evaporation and multistep unit-gradient experiments. Hydraulic properties of virtual stony soils were identified under a wide range of soil matric potentials. The developed models for scaling the hydraulic conductivity of stony soils were evaluated under unsaturated flow conditions.
Danielle L. Gelardi, Irfan H. Ainuddin, Devin A. Rippner, Janis E. Patiño, Majdi Abou Najm, and Sanjai J. Parikh
SOIL, 7, 811–825, https://doi.org/10.5194/soil-7-811-2021, https://doi.org/10.5194/soil-7-811-2021, 2021
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Biochar is purported to alter soil water dynamics and reduce nutrient loss when added to soils, though the mechanisms are often unexplored. We studied the ability of seven biochars to alter the soil chemical and physical environment. The flow of ammonium through biochar-amended soil was determined to be controlled through chemical affinity, and nitrate, to a lesser extent, through physical entrapment. These data will assist land managers in choosing biochars for specific agricultural outcomes.
Frederic Leuther and Steffen Schlüter
SOIL, 7, 179–191, https://doi.org/10.5194/soil-7-179-2021, https://doi.org/10.5194/soil-7-179-2021, 2021
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Freezing and thawing cycles are an important agent of soil structural transformation during the winter season in the mid-latitudes. This study shows that it promotes a well-connected pore system, fragments dense soil clods, and, hence, increases the unsaturated conductivity by a factor of 3. The results are important for predicting the structure formation and hydraulic properties of soils, with the prospect of milder winters due to climate change, and for farmers preparing the seedbed in spring.
Cosimo Brogi, Johan A. Huisman, Lutz Weihermüller, Michael Herbst, and Harry Vereecken
SOIL, 7, 125–143, https://doi.org/10.5194/soil-7-125-2021, https://doi.org/10.5194/soil-7-125-2021, 2021
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There is a need in agriculture for detailed soil maps that carry quantitative information. Geophysics-based soil maps have the potential to deliver such products, but their added value has not been fully investigated yet. In this study, we compare the use of a geophysics-based soil map with the use of two commonly available maps as input for crop growth simulations. The geophysics-based product results in better simulations, with improvements that depend on precipitation, soil, and crop type.
Jaqueline Stenfert Kroese, John N. Quinton, Suzanne R. Jacobs, Lutz Breuer, and Mariana C. Rufino
SOIL, 7, 53–70, https://doi.org/10.5194/soil-7-53-2021, https://doi.org/10.5194/soil-7-53-2021, 2021
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Particulate macronutrient concentrations were up to 3-fold higher in a natural forest catchment compared to fertilized agricultural catchments. Although the particulate macronutrient concentrations were lower in the smallholder agriculture catchment, because of higher sediment loads from that catchment, the total particulate macronutrient loads were higher. Land management practices should be focused on agricultural land to reduce the loss of soil carbon and nutrients to the stream.
Yongjiu Dai, Wei Shangguan, Nan Wei, Qinchuan Xin, Hua Yuan, Shupeng Zhang, Shaofeng Liu, Xingjie Lu, Dagang Wang, and Fapeng Yan
SOIL, 5, 137–158, https://doi.org/10.5194/soil-5-137-2019, https://doi.org/10.5194/soil-5-137-2019, 2019
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Soil data are widely used in various Earth science fields. We reviewed soil property maps for Earth system models, which can also offer insights to soil data developers and users. Old soil datasets are often based on limited observations and have various uncertainties. Updated and comprehensive soil data are made available to the public and can benefit related research. Good-quality soil data are identified and suggestions on how to improve and use them are provided.
Reuven B. Simhayov, Tobias K. D. Weber, and Jonathan S. Price
SOIL, 4, 63–81, https://doi.org/10.5194/soil-4-63-2018, https://doi.org/10.5194/soil-4-63-2018, 2018
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Lab experiments were performed to understand solute transport in peat from an experimental fen. Transport was analyzed under saturated and unsaturated conditions using NaCl (salt). We tested the applicability of a physical-based model which finds a wide consensus vs. alternative models. Evidence indicated that Cl transport can be explained using a simple transport model. Hence, use of the physical transport mechanism in peat should be evidence based and not automatically assumed.
Sami Touil, Aurore Degre, and Mohamed Nacer Chabaca
SOIL, 2, 647–657, https://doi.org/10.5194/soil-2-647-2016, https://doi.org/10.5194/soil-2-647-2016, 2016
M. J. Kirkby
SOIL, 2, 631–645, https://doi.org/10.5194/soil-2-631-2016, https://doi.org/10.5194/soil-2-631-2016, 2016
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The review paper surveys the state of the art with respect to water in the critical zone, taking a broad view that concentrates on the global range of natural soils, identifying some areas of currently active research.
Jean-Christophe Calvet, Noureddine Fritz, Christine Berne, Bruno Piguet, William Maurel, and Catherine Meurey
SOIL, 2, 615–629, https://doi.org/10.5194/soil-2-615-2016, https://doi.org/10.5194/soil-2-615-2016, 2016
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Soil thermal conductivity in wet conditions can be retrieved together with the soil quartz content using a reverse modelling technique based on sub-hourly soil temperature observations at three depths below the soil surface.
A pedotransfer function is proposed for quartz, for the considered region in France.
Gravels have a major impact on soil thermal conductivity, and omitting the soil organic matter information tends to enhance this impact.
Assefa D. Zegeye, Eddy J. Langendoen, Cathelijne R. Stoof, Seifu A. Tilahun, Dessalegn C. Dagnew, Fasikaw A. Zimale, Christian D. Guzman, Birru Yitaferu, and Tammo S. Steenhuis
SOIL, 2, 443–458, https://doi.org/10.5194/soil-2-443-2016, https://doi.org/10.5194/soil-2-443-2016, 2016
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Gully erosion rehabilitation programs in the humid Ethiopian highlands have not been effective, because the gully formation process and its controlling factors are not well understood. In this manuscript, the severity of gully erosion (onsite and offsite effect), the most controlling factors (e.g., ground water elevation) for gully formation, and their arresting mechanisms are discussed in detail. Most data were collected from the detailed measurements of 13 representative gullies.
Eléonore Beckers, Mathieu Pichault, Wanwisa Pansak, Aurore Degré, and Sarah Garré
SOIL, 2, 421–431, https://doi.org/10.5194/soil-2-421-2016, https://doi.org/10.5194/soil-2-421-2016, 2016
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Determining the behaviour of stony soils with respect to infiltration and storage of water is of major importance, since stony soils are widespread across the globe. The most common procedure to overcome this difficulty is to describe the hydraulic characteristics of a stony soils in terms of the fine fraction of soil corrected for the volume of stones present. Our study suggests that considering this hypothesis might be ill-founded, especially for saturated soils.
Mirjam J. D. Hack-ten Broeke, Joop G. Kroes, Ruud P. Bartholomeus, Jos C. van Dam, Allard J. W. de Wit, Iwan Supit, Dennis J. J. Walvoort, P. Jan T. van Bakel, and Rob Ruijtenberg
SOIL, 2, 391–402, https://doi.org/10.5194/soil-2-391-2016, https://doi.org/10.5194/soil-2-391-2016, 2016
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For calculating the effects of hydrological measures on agricultural production in the Netherlands a new comprehensive and climate proof method is being developed: WaterVision Agriculture (in Dutch: Waterwijzer Landbouw). End users have asked for a method that considers current and future climate, which can quantify the differences between years and also the effects of extreme weather events.
Mamaru A. Moges, Fasikaw A. Zemale, Muluken L. Alemu, Getaneh K. Ayele, Dessalegn C. Dagnew, Seifu A. Tilahun, and Tammo S. Steenhuis
SOIL, 2, 337–349, https://doi.org/10.5194/soil-2-337-2016, https://doi.org/10.5194/soil-2-337-2016, 2016
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In tropical monsoonal Africa, sediment concentration data in rivers are lacking. Using occasional historically observed sediment loads, we developed a simple method for prediction sediment concentrations. Unlike previous methods, our techniques take into account that sediment concentrations decrease with the progression of the monsoon rains. With more testing, the developed method could improve sediment predictions in monsoonal climates.
Didier Michot, Zahra Thomas, and Issifou Adam
SOIL, 2, 241–255, https://doi.org/10.5194/soil-2-241-2016, https://doi.org/10.5194/soil-2-241-2016, 2016
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This study focuses on temporal and spatial soil moisture changes along a toposequence crossed by a hedgerow, using ERT and occasional measurements. We found that the relationship between ER and soil moisture had two behaviors depending on soil heterogeneities. ER values were consistent with occasional measurements outside the root zone. The shift in this relationship was controlled by root system density and a particular topographical context in the proximity of the hedgerow.
Maha Deeb, Michel Grimaldi, Thomas Z. Lerch, Anne Pando, Agnès Gigon, and Manuel Blouin
SOIL, 2, 163–174, https://doi.org/10.5194/soil-2-163-2016, https://doi.org/10.5194/soil-2-163-2016, 2016
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This paper addresses the evolution of engineered soils (i.e., Technosols). The formation of such soils begins with proportional mixing of urban waste. Technosols are particularly well suited for investigating the role of organisms in soil function development. This is because they provide a controlled environment where the soil development can be monitored over time.
Organisms and their interaction with parent materials positively affect the structure of Technosols.
Z. Hazbavi and S. H. R. Sadeghi
SOIL, 2, 71–78, https://doi.org/10.5194/soil-2-71-2016, https://doi.org/10.5194/soil-2-71-2016, 2016
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This study evaluates the influences of vinasse waste of sugarcane industries on runoff and soil loss at small plot scale. Laboratory results indicated that the vinasse at different levels could not significantly (P > 0.05) decrease the runoff amounts and soil loss rates in the study plots compared to untreated plots. The average amounts of minimum runoff volume and soil loss were about 3985 mL and 46 g for the study plot at a 1 L m−2 level of vinasse application.
S. Arnold and E. R. Williams
SOIL, 2, 41–48, https://doi.org/10.5194/soil-2-41-2016, https://doi.org/10.5194/soil-2-41-2016, 2016
Short summary
Short summary
Soil water models are used to design cover systems for containing hazardous waste following mining. Often, soil invertebrates are omitted from these calculations, despite playing a major role in soil development (nutrient cycling) and water pathways (seepage, infiltration). As such, soil invertebrates can influence the success of waste cover systems. We propose that experiments in glasshouses, laboratories and field trials on mined lands be undertaken to provide knowledge for these models.
R. M. Nagare, P. Bhattacharya, J. Khanna, and R. A. Schincariol
SOIL, 1, 103–116, https://doi.org/10.5194/soil-1-103-2015, https://doi.org/10.5194/soil-1-103-2015, 2015
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Short summary
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.
The concept of soil aggregates is hotly debated, leading to confusion about their function or...
