Articles | Volume 7, issue 1
https://doi.org/10.5194/soil-7-53-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/soil-7-53-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Particulate macronutrient exports from tropical African montane catchments point to the impoverishment of agricultural soils
Jaqueline Stenfert Kroese
CORRESPONDING AUTHOR
Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, United Kingdom
Centre for International Forestry Research (CIFOR), c/o World Agroforestry Centre (ICRAF), Nairobi, 00100 Kenya
John N. Quinton
Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, United Kingdom
Suzanne R. Jacobs
Centre for International Development and Environmental Research (ZEU), Justus Liebig University Giessen, 35390 Giessen, Germany
Lutz Breuer
Institute for Landscape Ecology and Resources Management (ILR), Justus Liebig University Giessen, 35392 Giessen, Germany
Centre for International Development and Environmental Research (ZEU), Justus Liebig University Giessen, 35390 Giessen, Germany
Mariana C. Rufino
Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, United Kingdom
Centre for International Forestry Research (CIFOR), c/o World Agroforestry Centre (ICRAF), Nairobi, 00100 Kenya
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John N. Quinton, Gabriel Yesuf, German Baldi, Mengyi Gong, Kelvin Kinuthia, Ellen L. Fry, Yuda Odongo, Barthelemew Nyakundi, Joseph Hitimana, Patricia de Britto Costa, Alice A. Onyango, Sonja M. Leitner, Richard D. Bardgett, and Mariana C. Rufino
EGUsphere, https://doi.org/10.5194/egusphere-2025-3722, https://doi.org/10.5194/egusphere-2025-3722, 2025
This preprint is open for discussion and under review for SOIL (SOIL).
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We investigated how the soil degradation status of smallholder grazing, classified using remote sensing, in two districts of Western Kenya, compared with measured soil parameters at 90 sites. Grouping sites using soil data had some agreement with the remote sensing (RS) classification. Overall, our results suggest that supplementing RS methods with microbial biomass C, soil P, percent C and N, and soil pH, could enhance our ability to identify degraded soils and target restoration efforts.
Karl Auerswald, Juergen Geist, John N. Quinton, and Peter Fiener
Hydrol. Earth Syst. Sci., 29, 2185–2200, https://doi.org/10.5194/hess-29-2185-2025, https://doi.org/10.5194/hess-29-2185-2025, 2025
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Floods, droughts, and heatwaves are increasing globally. This is often attributed to CO2-driven climate change. However, at the global scale, CO2-driven climate change neither reduces precipitation nor adequately explains droughts. Land-use change, particularly soil sealing, compaction, and drainage, is likely to be more significant for water losses by runoff leading to flooding and water scarcity and is therefore an important part of the solution to mitigate floods, droughts, and heatwaves.
Max Weißenborn, Lutz Breuer, and Tobias Houska
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2024-183, https://doi.org/10.5194/hess-2024-183, 2024
Revised manuscript accepted for HESS
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Our study compares neural network models for predicting discharge in ungauged basins. We evaluated Convolutional Neural Networks (CNN), Long Short-Term Memory (LSTM) and Gated Recurrent Units (GRU) using 28 years of weather data. CNN showed the best accuracy, while GRU were faster and nearly as accurate. Adding static features improved all models. The research enhances flood forecasting and water management in regions lacking direct measurements, offering efficient and accurate predictive tools.
Elizabeth Gachibu Wangari, Ricky Mwangada Mwanake, Tobias Houska, David Kraus, Gretchen Maria Gettel, Ralf Kiese, Lutz Breuer, and Klaus Butterbach-Bahl
Biogeosciences, 20, 5029–5067, https://doi.org/10.5194/bg-20-5029-2023, https://doi.org/10.5194/bg-20-5029-2023, 2023
Short summary
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Agricultural landscapes act as sinks or sources of the greenhouse gases (GHGs) CO2, CH4, or N2O. Various physicochemical and biological processes control the fluxes of these GHGs between ecosystems and the atmosphere. Therefore, fluxes depend on environmental conditions such as soil moisture, soil temperature, or soil parameters, which result in large spatial and temporal variations of GHG fluxes. Here, we describe an example of how this variation may be studied and analyzed.
Ricky Mwangada Mwanake, Gretchen Maria Gettel, Elizabeth Gachibu Wangari, Clarissa Glaser, Tobias Houska, Lutz Breuer, Klaus Butterbach-Bahl, and Ralf Kiese
Biogeosciences, 20, 3395–3422, https://doi.org/10.5194/bg-20-3395-2023, https://doi.org/10.5194/bg-20-3395-2023, 2023
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Despite occupying <1 %; of the globe, streams are significant sources of greenhouse gas (GHG) emissions. In this study, we determined anthropogenic effects on GHG emissions from streams. We found that anthropogenic-influenced streams had up to 20 times more annual GHG emissions than natural ones and were also responsible for seasonal peaks. Anthropogenic influences also altered declining GHG flux trends with stream size, with potential impacts on stream-size-based spatial upscaling techniques.
Roisin O'Riordan, Jess Davies, Carly Stevens, and John N. Quinton
SOIL, 7, 661–675, https://doi.org/10.5194/soil-7-661-2021, https://doi.org/10.5194/soil-7-661-2021, 2021
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As urban populations grow, soil sealing with impermeable surfaces will increase. At present there is limited knowledge on the effect of sealing on soil carbon and nutrients. We found that, in general, sealing reduced soil carbon and nutrients; however, where there were additions due to human activity, soil carbon and nutrients were increased. This suggests that there is a legacy soil carbon store in areas with an industrial past and highlights the influence of artefacts in urban soil.
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Short summary
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.
Particulate macronutrient concentrations were up to 3-fold higher in a natural forest catchment...