Articles | Volume 7, issue 1
SOIL, 7, 53–70, 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Original research article 15 Mar 2021
Original research article | 15 Mar 2021
Particulate macronutrient exports from tropical African montane catchments point to the impoverishment of agricultural soils
Jaqueline Stenfert Kroese et al.
No articles found.
Roisin O'Riordan, Jess Davies, Carly Stevens, and John N. Quinton
Preprint under review for SOILShort summary
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 of material due to human activity, soil carbon and nutrients were increased. This suggests there is a legacy soil carbon store in areas with an industrial past and highlights the influence of artefacts in urban soil.
Amani Mahindawansha, Christoph Külls, Philipp Kraft, and Lutz Breuer
Hydrol. Earth Syst. Sci., 24, 3627–3642,Short summary
Stable isotopes of soil water are an effective tool to reveal soil hydrological processes in irrigated agricultural fields. Flow mechanisms and isotopic patterns of soil water in the soil matrix differ, depending on the crop and irrigation practices. Isotope data supported the fact that unproductive water losses via evaporation can be reduced by introducing dry seasonal crops to the crop rotation system.
Michael C. Thrun, Alfred Ultsch, and Lutz Breuer
Geosci. Model Dev. Discuss.,
Revised manuscript not acceptedShort summary
We propose an explainable AI (XAI) framework for times series describing water quality & environmental parameters. The relationship between parameters is investigated by swarm based cluster analysis designed to find similar days within & dissimilar days between clusters. Resulting clusters define three states of water bodies & are visualized by a topographic map of high-dimensional structures. Rules generated by the XAI system explain clusters & improve the understanding of aquatic environments.
Florian U. Jehn, Konrad Bestian, Lutz Breuer, Philipp Kraft, and Tobias Houska
Hydrol. Earth Syst. Sci., 24, 1081–1100,Short summary
We grouped 643 rivers from the United States into 10 behavioral groups based on their hydrological behavior (e.g., how much water they transport overall). Those groups are aligned with the ecoregions in the United States. Depending on the groups’ location and other characteristics, either snow, aridity or seasonality is most important for the behavior of the rivers in a group. We also find that very similar river behavior can be found in rivers far apart and with different characteristics.
Sebastian Multsch, Maarten S. Krol, Markus Pahlow, André L. C. Assunção, Alberto G. O. P. Barretto, Quirijn de Jong van Lier, and Lutz Breuer
Hydrol. Earth Syst. Sci., 24, 307–324,Short summary
Expanding irrigation in agriculture is one of Brazil's strategies to increase production. In this study the amount of water required to grow the main crops has been calculated and compared to the water that is available in rivers at least 95 % of the time. Future decisions regarding expanding irrigated cropping areas must, while intensifying production practices, consider the likely regional effects on water scarcity levels, in order to reach sustainable agricultural production.
Daniel L. Evans, John N. Quinton, Andrew M. Tye, Ángel Rodés, Jessica A. C. Davies, Simon M. Mudd, and Timothy A. Quine
SOIL, 5, 253–263,Short summary
Policy to conserve thinning arable soils relies on a balance between the rates of soil erosion and soil formation. Our knowledge of the latter is meagre. Here, we present soil formation rates for an arable hillslope, the first of their kind globally, and a woodland hillslope, the first of their kind in Europe. Rates range between 26 and 96 mm kyr−1. On the arable site, erosion rates are 2 orders of magnitude greater, and in a worst-case scenario, bedrock exposure could occur in 212 years.
Suzanne R. Jacobs, Edison Timbe, Björn Weeser, Mariana C. Rufino, Klaus Butterbach-Bahl, and Lutz Breuer
Hydrol. Earth Syst. Sci., 22, 4981–5000,Short summary
This study investigated how land use affects stream water sources and flow paths in an East African tropical montane area. Rainfall was identified as an important stream water source in the forest and smallholder agriculture sub-catchments, while springs were more important in the commercial tea plantation sub-catchment. However, 15 % or less of the stream water consisted of water with an age of less than 3 months, indicating that groundwater plays an important role in all land use types.
Florian U. Jehn, Lutz Breuer, Tobias Houska, Konrad Bestian, and Philipp Kraft
Hydrol. Earth Syst. Sci., 22, 4565–4581,Short summary
By realizing that hydrological models are not one single hypothesis, but an assemblage of many hypotheses, new ways to scrutinize hydrological models are needed. Up until now, studies concentrate on comparing existing models or built models incrementally. This approach here tries to tackle the problem the other way around. We construct a complex model, containing all processes important for the catchment, and deconstruct it step by step to understand the influence of single processes.
Natalie Orlowski, Lutz Breuer, Nicolas Angeli, Pascal Boeckx, Christophe Brumbt, Craig S. Cook, Maren Dubbert, Jens Dyckmans, Barbora Gallagher, Benjamin Gralher, Barbara Herbstritt, Pedro Hervé-Fernández, Christophe Hissler, Paul Koeniger, Arnaud Legout, Chandelle Joan Macdonald, Carlos Oyarzún, Regine Redelstein, Christof Seidler, Rolf Siegwolf, Christine Stumpp, Simon Thomsen, Markus Weiler, Christiane Werner, and Jeffrey J. McDonnell
Hydrol. Earth Syst. Sci., 22, 3619–3637,Short summary
To extract water from soils for isotopic analysis, cryogenic water extraction is the most widely used removal technique. This work presents results from a worldwide laboratory intercomparison test of cryogenic extraction systems. Our results showed large differences in retrieved isotopic signatures among participating laboratories linked to interactions between soil type and properties, system setup, extraction efficiency, extraction system leaks, and each lab’s internal accuracy.
Tobias Houska, David Kraus, Ralf Kiese, and Lutz Breuer
Biogeosciences, 14, 3487–3508,Short summary
CO2 and N2O are two prominent GHGs contributing to global warming. We combined measurement and modelling to quantify GHG emissions from adjacent arable, forest and grassland sites in Germany. Measured emissions reveal seasonal patterns and management effects like fertilizer application, tillage, harvest and grazing. Modelling helps to estimate the magnitude and uncertainty of not measurable C and N fluxes and indicates missing input source, e.g. nitrate uptake from groundwater.
David Pelster, Mariana Rufino, Todd Rosenstock, Joash Mango, Gustavo Saiz, Eugenio Diaz-Pines, German Baldi, and Klaus Butterbach-Bahl
Biogeosciences, 14, 187–202,Short summary
In order to quantify greenhouse gas fluxes from typical eastern African smallholder farms, we measured flux rates every week for 1 year at 59 farms in western Kenya. These upland soils tend to be small sinks for CH4 and small sources of N2O. The management intensity of the farm plots had no effect on emissions, likely because the variability was low. Plots with trees had higher CH4 uptake than other plots. This suggests that emissions from small, low-input farms in this region are quite low.
Rosa Maria Roman-Cuesta, Martin Herold, Mariana C. Rufino, Todd S. Rosenstock, Richard A. Houghton, Simone Rossi, Klaus Butterbach-Bahl, Stephen Ogle, Benjamin Poulter, Louis Verchot, Christopher Martius, and Sytze de Bruin
Biogeosciences, 13, 5799–5819,Short summary
The land use sector (AFOLU) is a pivotal component of countries' mitigation commitments under the Paris Agreement. Global land use data are therefore important to complement and fill in countries' data gaps. But how different are the existing AFOLU datasets and why? Here we contrast six AFOLU datasets for the tropics at different levels of aggregation (spatial, gases, emission sources) and point out possible reasons for the observed differences and the next steps to improve land use emissions.
Natalie Orlowski, Philipp Kraft, Jakob Pferdmenges, and Lutz Breuer
Hydrol. Earth Syst. Sci., 20, 3873–3894,Short summary
The 2-year measurements of δ2H and δ18O in rainfall, stream, soil, and groundwater revealed that surface and groundwater are isotopically disconnected from the annual precipitation cycle but showed bidirectional interactions in the Schwingbach catchment. We established a hydrological model to estimate spatially distributed groundwater ages and flow directions. Our model revealed complex age dynamics and showed that runoff must have been stored in the catchment for much longer than event water.
Rosa Maria Roman-Cuesta, Mariana C. Rufino, Martin Herold, Klaus Butterbach-Bahl, Todd S. Rosenstock, Mario Herrero, Stephen Ogle, Changsheng Li, Benjamin Poulter, Louis Verchot, Christopher Martius, John Stuiver, and Sytze de Bruin
Biogeosciences, 13, 4253–4269,Short summary
This research provides spatial data on gross emissions from the land use sector for the tropical region for the period 2000–2005. This sector contributes up to 24 % of the global emissions, but there is little understanding of where the hotspots of emissions are, how uncertain they are, and what the human activities behind these emissions are. Data provided here should assist countries to identify priority areas for mitigation action and contrast the effectiveness of their current measures.
Giovanny M. Mosquera, Catalina Segura, Kellie B. Vaché, David Windhorst, Lutz Breuer, and Patricio Crespo
Hydrol. Earth Syst. Sci., 20, 2987–3004,Short summary
This study focuses on the investigation of baseflow mean transit times (MTTs) in a high-elevation tropical ecosystem (páramo) using stable water isotopes. Results showed short MTTs (< 9 months) and topographic controls on their spatial variability. We conclude that (1) the hydrology of the ecosystem is dominated by shallow subsurface flow and (2) the interplay between the high storage capacity of the páramo soils and the catchments' slopes provides the ecosystem with high regulation capacity.
Saskia D. Keesstra, Johan Bouma, Jakob Wallinga, Pablo Tittonell, Pete Smith, Artemi Cerdà, Luca Montanarella, John N. Quinton, Yakov Pachepsky, Wim H. van der Putten, Richard D. Bardgett, Simon Moolenaar, Gerben Mol, Boris Jansen, and Louise O. Fresco
SOIL, 2, 111–128,Short summary
Soil science, as a land-related discipline, has links to several of the UN Sustainable Development Goals which are demonstrated through the functions of soils and related ecosystem services. We discuss how soil scientists can rise to the challenge both internally and externally in terms of our relations with colleagues in other disciplines, diverse groups of stakeholders and the policy arena. To meet these goals we recommend the set of steps to be taken by the soil science community as a whole.
A. H. Aubert, O. Schnepel, P. Kraft, T. Houska, I. Plesca, N. Orlowski, and L. Breuer
Hydrol. Earth Syst. Sci. Discuss.,
Revised manuscript not acceptedShort summary
Studienlandschaft Schwingbachtal is an out-door full-scale study site since 2008. It deals with hydrology in an interdisciplinary approach and enhances active learning by various means (field monitoring, education trails and geocache). In order to adapt to the change in students habits and to suit better as a communication tool for the locals, it is newly equipped with augmented reality which adds virtual objects on the real landscape, making learning pleasant.
A. Ola, I. C. Dodd, and J. N. Quinton
SOIL, 1, 603–612,Short summary
Plant roots are crucial in soil erosion control. Moreover, some species respond to nutrient-rich patches by lateral root proliferation. At the soil surface dense mats of roots may block soil pores thereby limiting infiltration, enhancing runoff; whereas at depth local increases in shear strength may reinforce soils at the shear plane. This review considers the potential of manipulating plant roots to control erosion.
S. Carter, M. Herold, M. C. Rufino, K. Neumann, L. Kooistra, and L. Verchot
Biogeosciences, 12, 4809–4825,Short summary
Emission from agriculture-driven deforestation can be mitigated by reducing the expansion of agriculture into forests through intensification and utilizing non-forested land for agriculture. Climate-smart agriculture can reduce emissions from existing agricultural land. Tropical countries which are priorities for action can be identified by assessing the mitigation potential of these interventions, by assessing capacity for implementation and the risks associated with these approaches.
S. Multsch, J.-F. Exbrayat, M. Kirby, N. R. Viney, H.-G. Frede, and L. Breuer
Geosci. Model Dev., 8, 1233–1244,Short summary
Irrigation agriculture is required to sustain yields that allow feeding the world population. A robust assessment of irrigation requirement (IRR) relies on a sound quantification of evapotranspiration (ET). We prepared a multi-model ensemble considering several ET methods and investigate uncertainties in simulating IRR. More generally, we provide an example of the value of investigating the uncertainty in models that may be used to inform policy-making and to elaborate best management practices.
E. Timbe, D. Windhorst, R. Celleri, L. Timbe, P. Crespo, H.-G. Frede, J. Feyen, and L. Breuer
Hydrol. Earth Syst. Sci., 19, 1153–1168,Short summary
Stream, soil and precipitation waters were collected in a tropical montane cloud forest catchment for 2 years and analyzed for stable water isotopes in order to infer transit time distribution functions and mean transit times for semi-steady-state conditions. Samples were aggregated to diverse sampling resolutions for checking the sensitivity of sampling frequency on lumped-model predictions. Results provide valuable information for the planning of future fieldwork in similar catchments.
E. C. Brevik, A. Cerdà, J. Mataix-Solera, L. Pereg, J. N. Quinton, J. Six, and K. Van Oost
SOIL, 1, 117–129,Short summary
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.
D. Windhorst, P. Kraft, E. Timbe, H.-G. Frede, and L. Breuer
Hydrol. Earth Syst. Sci., 18, 4113–4127,
E. Timbe, D. Windhorst, P. Crespo, H.-G. Frede, J. Feyen, and L. Breuer
Hydrol. Earth Syst. Sci., 18, 1503–1523,
N. Orlowski, H.-G. Frede, N. Brüggemann, and L. Breuer
J. Sens. Sens. Syst., 2, 179–193,
S. Multsch, Y. A. Al-Rumaikhani, H.-G. Frede, and L. Breuer
Geosci. Model Dev., 6, 1043–1059,
D. Windhorst, T. Waltz, E. Timbe, H.-G. Frede, and L. Breuer
Hydrol. Earth Syst. Sci., 17, 409–419,
J.-F. Exbrayat, N. R. Viney, H.-G. Frede, and L. Breuer
Geosci. Model Dev., 6, 117–125,
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S. Arnold and E. R. Williams
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R. M. Nagare, P. Bhattacharya, J. Khanna, and R. A. Schincariol
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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.
Particulate macronutrient concentrations were up to 3-fold higher in a natural forest catchment...