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Soil loss by water erosion is one of the main threats to soil health and food production in intensively used agricultural areas. To assess its significance to the overall sediment production we applied the Water and Tillage Erosion Model/Sediment Delivery model (WaTEM/SEDEM) to the Luoyugou catchment, a sub-catchment of the Yellow River basin within the Chinese Loess plateau. WaTEM/SEDEM considers rill and inter-rill erosion and deposition rates, resulting in sediment yield rates leaving the catchment. Although terraces were established in the 1990s to reduce soil loss, no further soil erosion modeling has been published for this area. Applying 1000 Monte Carlo simulations of the WaTEM/SEDEM, modeled average soil loss by rill and inter-rill erosion for 2020 was 12.4 ± 11.8 t ha-1 yr-1, with sediment yield at the outlet of 52949 ± 11215 t yr-1. Terracing reduced erosion rates, while land cover changes, mainly conversion of forests and grassland partly counteracted the mitigation (combined effect: 50% reduction). Modeled sediment loads by rill and inter-rill erosion account for 17.1% of the total long-term sediment production recorded by flow discharge measurements. Other processes not considered by the model like landslides, gully erosion, riverbank erosion, and sediment production by construction seem to dominate overall sediment yield. Considering years with baseline sediment production only, measured and modeled sediment yield compared well, indicating that the latter processes contribute mainly during extreme events.

Soil erosion and sediment export from hillslopes are significant problems associated with agriculture, especially in parts of the world where society is already living in extreme environments. In particular, mountainous environments remain severely understudied, with only a few runoff and sediment transport measurements available. It is necessary, therefore, to develop and validate independent methods that do not rely on long-term observations at gauging stations. Here we used three independent methods to predict soil erosion and associated sediment yield (SY) from a 1.84 km² basin in the North Caucasus. The first part concerns assessing the sedimentation rate, which was made using in-situ measurements of volumetric sediment deposition rates. Secondly, we look at the connectivity of sediment sources and the lake. A combination of remote sensing data and field surveys was used to estimate sediment connectivity and erosion mapping. The third part regards the computation of soil erosion using the Revised Universal Soil Loss Equation (RUSLE). There are three major findings in this study that help us understand sediment redistribution patterns in mountainous areas. First, based on the lake sedimentation rate, we found that the mean annual area-specific sediment yield is 514 (95% CI, 249–839) t km− 2 yr− 1. Similar results were obtained from the erosion mapping (i.e., a map of erosion processes) — 428 (95% CI, 322–546) t km− 2 yr− 1. Secondly, the spatial distribution and rates of the erosion processes suggest that sheet and rill erosion are responsible for ca. 40% of total sediment export, slides and rockfalls — 18%, while the rest is removed by soil creep. Additionally, the RUSLE-based modelling of sheet wash and rill erosion has highlighted the areas most prone to soil erosion. The corresponding mean annual soil erosion rate of 1.59 mm yr− 1 was very close to the results obtained from the literature review.

The interaction between abiotic and biotic development in glacier forelands depends on species traits and the frequency and magnitude of geomorphic events as shown on plot-scale studies. However, upscaling of biogeomorphic interactions is still scarce and it remains unclear how these interactions form and shape dynamic patches.In this study, we combined traditional field based methods of geomorphology and ecology with remote sensing and soil erosion modelling. Geomorphic mapping allows the delineation of process domains for further methods specification. Field based plot sampling along a chronosequences provides insight into distribution of species composition. Catchment wide patterns of functional groups of vegetation (graminoids, forbs, woody) were analyzed with a random forest algorithm using UAV-based multispectral imagery recorded. Small scale geomorphic events are described through simulated annual sediment transport rates derived from the revised universal soil loss equation model (RUSLE).The dataset will show temporal and spatial distribution of the stabilizing effect of plant functional types. Analyses of potential erosion rates will show the relationship of small scale sediment transport with species distribution. Results of this study will contribute to our understanding of processes that form biogeomorphic landscape patterns in glacier forelands at different scales.

The accelerated sediment supply from agricultural soils to riverine and lacustrine environments leads to negative off-site consequences. In particular, the sediment connectivity from agricultural land to surface waters is strongly affected by landscape patchiness and the linear structures that separate field parcels (e.g. roads, tracks, hedges, and grass buffer strips). Understanding the interactions between these structures and sediment transfer is therefore crucial for minimising off-site erosion impacts. Although soil erosion models can be used to understand lateral sediment transport patterns, model-based connectivity assessments are hindered by the uncertainty in model structures and input data. Specifically, the representation of linear landscape features in numerical soil redistribution models is often compromised by the spatial resolution of the input data and the quality of the process descriptions. Here we adapted the Water and Tillage Erosion Model and Sediment Delivery Model (WaTEM/SEDEM) using high-resolution spatial data (2 m × 2 m) to analyse the sediment connectivity in a very patchy mesoscale catchment (73 km2) of the Swiss Plateau. We used a global sensitivity analysis to explore model structural assumptions about how linear landscape features (dis)connect the sediment cascade, which allowed us to investigate the uncertainty in the model structure. Furthermore, we compared model simulations of hillslope sediment yields from five subcatchments to tributary sediment loads, which were calculated with long-term water discharge and suspended sediment measurements. The sensitivity analysis revealed that the assumptions about how the road network (dis)connects the sediment transfer from field blocks to water courses had a much higher impact on modelled sediment yields than the uncertainty in model parameters. Moreover, model simulations showed a higher agreement with tributary sediment loads when the road network was assumed to directly connect sediments from hillslopes to water courses. Our results ultimately illustrate how a high-density road network combined with an effective drainage system increases sediment connectivity from hillslopes to surface waters in agricultural landscapes. This further highlights the importance of considering linear landscape features and model structural uncertainty in soil erosion and sediment connectivity research.

Various large-scale risk maps show that the eastern part of Austria, in particular the Pannonian Basin, is one of the regions in Europe most vulnerable to wind erosion. However, comprehensive assessments of the severity and the extent of wind erosion risk are still lacking for this region. This study aimed to prove the results of large-scale maps by developing high-resolution maps of wind erosion risk for the target area. For this, we applied a qualitative soil erosion assessment (DIN 19706) with lower data requirements and a more data-demanding revised wind erosion equation (RWEQ) within a GIS application to evaluate the process of assessing wind erosion risk. Both models defined similar risk areas, although the assignment of severity classes differed. Most agricultural fields in the study area were classified as not at risk to wind erosion (DIN 19706), whereas the mean annual soil loss rate modeled by RWEQ was 3.7 t ha−1 yr−1. August was the month with the highest modeled soil loss (average of 0.49 t ha−1 month−1), due to a low percentage of vegetation cover and a relatively high weather factor combining wind speed and soil moisture effects. Based on the results, DIN 19706 is suitable for a general classification of wind erosion-prone areas, while RWEQ can derive additional information such as seasonal distribution and soil loss rates besides the spatial extents of wind erosion.

The accelerated sediment supply from agricultural soils to riverine and lacustrine environments leads to negative off-site consequences. In particular, the sediment connectivity from agricultural land to surface waters is strongly affected by landscape patchiness and the linear structures that separate field parcels (e.g. roads, tracks, hedges, and grass-buffer-strips). Understanding the feedbacks between these structures and sediment transfer is therefore crucial for minimising off-site erosion impacts. Although soil erosion models can be used to understand lateral sediment transport patterns, model-based connectivity assessments are hindered by the uncertainty in model structures and input data. In particular, the representation of linear landscape features in numerical soil redistribution models is often compromised by the spatial resolution of the input data and the quality of the process descriptions. Here we adapted the WaTEM/SEDEM model using high resolution spatial data (2 m × 2 m) to analyse the sediment connectivity in a very patchy mesoscale catchment (73 km2) of the Swiss Plateau. Specifically, we used a global sensitivity analysis to explore model structural assumptions about how linear landscape features (dis)connect the sediment cascade. Furthermore, we compared model simulations of hillslope sediment yields from five sub-catchments to tributary sediment loads, which were calculated with long-term water discharge and suspended sediment measurements. Our results showed that roads were the main regulators of sediment connectivity in the catchment. In particular, the sensitivity analysis revealed that the assumptions about how the road network (dis)connects the sediment transfer from field-blocks to water courses had a much higher impact on modelled sediment yields than the uncertainty in model parameters. Moreover, model simulations showed a higher agreement with tributary sediment loads when the road network was assumed to directly connect sediments from hillslopes to water courses. Our results ultimately illustrate how a high-density road network combined with an effective drainage system increase sediment connectivity from hillslopes to surface waters in this representative catchment of the Swiss Plateau. This further highlights the importance of considering linear structures in soil erosion and sediment connectivity models.

Wind erosion of arable soil is considered a risk factor for Austrian fields, but direct measurements of soil loss are not available until now. Despite this uncertainty, vegetated windbreaks have been established to minimize adverse wind impacts on arable land. The study addresses these questions: i) How relevant is wind erosion as a factor of soil degradation? ii) How important is the protective effect of vegetated windbreaks? iii) Are systematic patterns of spatial and temporal variability of wind erosion rates detectable in response to weather conditions? Two experimental fields adjacent to windbreaks were equipped with sediment traps, soil moisture sensors, and meteorological measurement equipment for microclimatic patterns. Sediment traps were arranged in high spatial resolution from next to the windbreak to a distance of ten times the windbreak height. Beginning in January 2020, the amount of trapped sediment was analyzed every three weeks. The highest wind erosion rates on bare soil were observed in June and July. For unprotected fields with bare soil, upscaled annual erosion rates were as high as 0.8 tons per hectare, and sediment trapped increased in a linear fashion with distance from the windbreak. Soil water content near the surface (5 cm depth) was three percent higher at a distance of two times the height of the windbreak than at a distance of six times the height. For the same respective distances from the windbreak, we observed 29 days of soil water contents below the wilting point compared with 60 days.The preliminary outcomes confirmed the expected effects of windbreaks on soil erosion and microclimate in agricultural fields. Prospective results from multiple vegetation periods will be used in an upscaling approach to gain informations for the whole basin. That is meant to be done by a combination with a soil wind erosion model which was so far used for regional modelling of wind erosion susceptibility.

Sediment connectivity is highly influenced by landscape patchiness. In particular, linear features such as roads, ditches, and terraces, modify landscape patterns and affect sediment transport from hillslopes to surface waters. Connectivity patterns are commonly assessed by spatially-distributed models, which rely on semi-qualitative indices or numerical simulations of soil erosion and sediment transport. However, model-based connectivity assessments are hindered by the uncertainty in model structure and parameter estimation. Moreover, representing linear landscape features is often limited by the spatial resolution of the model input data. Here we demonstrate how a global sensitivity analysis of the WaTEM/SEDEM model can be used to improve our understanding of sediment connectivity in patchy agricultural catchments of the Swiss Plateau. Specifically, we explored model structural connectivity assumptions regarding road drainage and the presence of edge-of-field buffer strips, as well as the uncertainty in the input data, by means of a Monte Carlo simulation and a high resolution 2 m x 2 m DEM. Our results showed that roads are the main regulators of sediment connectivity in ameliorated Swiss landscapes. That is, our sensitivity analysis revealed that assumptions about how the road network (dis)connects sediment transport from cropland to water courses had a much higher impact on modelled sediment loads than the uncertainty in model parameters. These results illustrate how a high-density road network combined with an effective drainage system increases sediment connectivity from arable land to surface waters in Switzerland. Additionally, our approach underlines the usefulness of sensitivity and uncertainty analysis for identifying relevant processes in model-based sediment connectivity assessments.

The degrading impact of wind on agricultural soils has been observed throughout centuries in the Pannonian region of central Europe. Nevertheless, soil loss was not yet quantified and the extent or relevance of the problem are unknown for this agriculturally important region. Especially dry soil surface is highly prone to erosion and as drought periods are expected to become more frequent and severe with changing climate, the risk of wind erosion will increase accordingly. Living windbreaks and similar agro-forestry systems are supposed to be highly effective measures against wind erosion. In an extensive research project, multiple approaches are integrated to obtain a broad view onto the relevance of soil degradation by wind on plot scale and its regional distribution.More in detail, case studies are conducted where the soil loss by wind erosion is measured in sediment traps. Data about driving and stabilizing factors like wind speed, soil moisture, vegetation density etc. are measured in high spatial and temporal resolution. The measurements started in December 2019. Besides, wind erosion risk is modelled and mapped on regional scale applying state-of-the-art model procedures. The measurement results are used in an attempt to down-scale the model application and thus create a link to ground-truth data. Information about spatial and temporal variability of the driving factors is used for implementation of stochastic calculation procedures in a sensitivity study which determines the most relevant factors for wind erosion mitigation.The used modelling approach also includes the effects of wind shelters what enables a partly evaluation of the existing network of such elements in the Pannonian region. There, the Authority of Land Reform has been supporting and documenting the installation of wind shelters for more than 60 years. Incorporating this data base, quantitative and qualitative statements will be developed about the state of the shelter belts and their relevance concerning erosion rates. Additionally, the potential and actual value of living windbreaks will be determined with special regards to physiological and ecological characteristics, stability under future climate conditions and further ecosystem services in agricultural landscapes.

Windbreaks are key structural elements in the rural environment and affect the functionality of landscapes in multiple ways. A broad interdisciplinary view on these functions lacks in scientific literature and common knowledge. This led to under informed management decisions, a decrease in the number of windbreaks in wide areas, and a subsequent loss of landscape functionality. Therefore, the knowledge on windbreaks and associated ecosystem services (ES) was systematically reviewed to guide the way for a holistic comprehension of such structural landscape elements. We defined eight bundles of ES on the basis of the Common International Classification of ES scheme. Search terms that allowed to include only vegetative windbreaks consisting of at least one tree row were combined with appropriate search terms for the eight ES bundles in individual searches resulting in a total of 6094 hits. We considered only publications that provided quantitative data and allowed to derive a clear effect of windbreaks on ES so that 222 publications from all over the world were quantitatively and qualitatively analyzed. The outcomes provide information about the dimension of effort, scientific consensus or dissensus, and knowledge gaps in the different research disciplines involved. It was shown that windbreaks bring predominantly positive effects to landscapes in the course of all investigated ES bundles. Apparent positive effects were found for soil protection, biodiversity and pest control, whereas for biomass production, nutrient and water balance, also adverse or indifferent effects were reported. The present review reveals an intense need for further interdisciplinary research using indicators, ES approaches or similar instruments that enable quantitative and comparable statements about the functionality of windbreaks in rural landscapes.

[This corrects the article DOI: 10.1016/j.mex.2019.01.004.]., (© 2019 The Authors.)