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Soil redistribution on arable land is a major threat for a sustainable use of soil resources. The majority of soil redistribution studies focus on water erosion, while wind and tillage erosion also induce pronounced redistribution of soil materials. Tillage erosion especially is understudied, as it does not lead to visible off-site damages. The analysis of on-site/in-field soil redistribution is mostly based on tracer studies, where radionuclide tracers (e.g. 137 Cs, 239+240Pu) from nuclear weapon tests are commonly used to derive the erosion history over the past 50–60 years. Tracer studies allow us to determine soil redistribution patterns but integrate all types of soil redistribution processes and hence do not allow us to unravel the contribution of individual erosion processes. The aim of this study is to understand the contribution of water and tillage erosion leading to soil patterns found in a small hummocky ground moraine kettle hole catchment under intensive agricultural use. Therefore, 239+240Pu -derived soil redistribution patterns were analysed using an inverse modelling approach accounting for water and tillage erosion processes. The results of this analysis clearly point out that tillage erosion is the dominant process of soil redistribution in the study catchment, which also affects the hydrological and sedimentological connectivity between arable land and the kettle hole. A topographic change up to 17 cm (53 yr) -1 in the eroded parts of the catchment is not able to explain the current soil profile truncation that exceeds the 239+240Pu -derived topographic change substantially. Hence, tillage erosion already started before the onset of intense mechanisation since the 1960s. In general, the study stresses the urgent need to consider tillage erosion as a major soil degradation process that can be the dominant soil redistribution process in sloped arable landscapes. [ABSTRACT FROM AUTHOR]

The identification of buried soil horizons in agricultural landscapes helps to quantify sediment budgets and erosion‐related carbon dynamics. High‐resolution mapping of buried horizons using conventional soil surveys is destructive and time consuming. Geoelectrical sensors can offer a fast and non‐destructive alternative for determining horizon positions and properties. In this paper, we compare the suitability of several geoelectrical methods for measuring the depth to buried horizons (Apb, Ahb and Hab) in the hummocky ground moraine landscape of northeastern Germany. Soil profile descriptions were developed for 269 locations within a 6‐ha experimental field "CarboZALF‐D". A stepwise linear discriminant analysis (LDA) estimated the lateral position of the buried horizons using electromagnetic induction data and terrain attributes. To predict the depth of a buried horizon, multiple linear regression (MLR) was used for both a 120‐m transect and a 0.2‐ha pseudo‐three‐dimensional (3D) area. At these scales, apparent electrical conductivity (ECa), electrical resistivity (ER) and terrain attributes were used as independent variables. The LDA accurately predicted Apb‐ and Ahb‐horizons (a correct classification of 93%). The LDA of the Hab‐horizon had a misclassification of 24%, which was probably related to the smaller test set and the higher depth of this horizon. The MLR predicted the depth of the Apb‐, Ahb‐ and Hab‐horizons with relative root mean square errors (RMSEs) of 7, 3 and 13%, respectively, in the pseudo‐3D area. MLR had a lower accuracy for the 2D transect compared to the pseudo‐3D area. Overall, the use of LDA and MLR has been an efficient methodological approach for predicting buried horizon positions. Highlights: The suitability of geoelectrical measurements for digital modelling of diagnostic buried soil horizons was determined.LDA and MLR were used to detect multiple horizons with geoelectrical devices and terrain attributes.Geoelectrical variables were significant predictors of the position of the target soil horizons.The use of these tested digital technologies gives an opportunity to develop high‐resolution soil mapping procedures. [ABSTRACT FROM AUTHOR]