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Due to changing climate and irregular weather patterns, event-based soil loss and sediment yield have become important issues in the agricultural areas. Several mathematical models and prediction methodologies have been used to estimate event-based soil loss and soil redistribution based on soil types, land management, hydrology and local topography. The use of short-lived beryllium-7 as a means of estimating event-based soil erosion/deposition rates has become an alternative to the traditional soil loss measurement methods. A new erosion model taking into account the movement of 7Be in soils has been presented recently. In order to direct the attention to the potential offered by this technique (measurements and mathematical model), a two-year study was performed at the erosion plots in Müncheberg, Germany, and twelve individual erosion rates were estimated. This paper presents a systematic comparison of the non-steady state 7Be model with the process-based erosion model EROSION-3D and measured data. The results demonstrate a close consistency between the erosion rates estimated by erosion models and the estimates provided by the 7Be model and can therefore be seen as a promising contribution to validating the use of this radionuclide to document short-term soil redistribution within the plot and deposited sediment at the bottom of the plot. [ABSTRACT FROM AUTHOR]

Abstract: The paper presents a comparative method (SICOM) to evaluate complex site conditions at different area units as a basis for the estimate of spatial equivalence of agri-environmental measures (AEM). The methodology uses primary site condition data and provides the possibility to compare these data objectively and evaluate different ecological questions. The linking of classified data and spatial equivalence data opens up new possibilities to localize areas of high/low environmental effectiveness (e.g. erosion risk) and to assess the ratio of AEM implementation (acceptance) versus financial input. The use of SICOM is demonstrated for water and wind erosion risk assessment at different scales in the federal state Brandenburg (Germany). The “parcel” aggregation level proves adequate to assess the erosion risk. Larger scales are less useful in the assessment of subsidies policy with regard to erosion risk. A combination of the GIS-moving-window-technique with SICOM establishes the possibility of comparing regions independent of spatial patterns within the landscape. [Copyright &y& Elsevier]

A methodology is presented for identifying and assessing source areas of sediment, phosphorus and nitrate emissions into surface waters and river systems of the South Baltic unconsolidated rock region by water erosion. This task is included into the characterization of the pressures and impacts in river basins as an important milestone in implementing the EC Water Framework Directive set out by 2004. The Nutrient Input Into River Systems (NIIRS) approach has been developed and tested in the Odra river basin in Poland, Czech Republic and Germany. Mesoscale distributed analyses are facilitated for identifying erosion risk areas with non-point phosphorus and nitrate inputs into water bodies via surface flow. Using statistical information and available geodata, analyses are based on empirical (NIIRS), but preferably process-oriented modelling (EROSION-3D). Thus, besides better understanding the system behaviour, detailed quantitative knowledge of spatial nutrient export rates from potential source areas will be acquired. The application of the distributed approaches is demonstrated in the entire Odra River basin and its sub-catchment Uecker River. Additionally spatial effects are shown for the field scale transfer of eroded material in the Uecker sub-catchment by using the physically based model EROSION-3D. Scenario calculations incorporated into a Geographical Information System (GIS) environment are feasible for estimating the development of erosion risk as well as N and P loads entering water bodies. Supplemented by impact analyses of land use changes, the methodology can serve as physical precondition for the cost-benefit oriented allocation of mitigation strategies. [ABSTRACT FROM AUTHOR]

This paper presents a comparative method (VERMOST) to evaluate complex site conditions at the level of a federal state (Brandenburg) and at different areal units. The methodology uses primary site conditions and provides the possibility to objectively compare and judge different ecological questions. Objects with heterogeneous content are pooled in comparison groups. Considering the main site characteristics allows a goal-oriented allocation of subsidies. The use of VERMOST is demonstrated for the wind and water erosion risk assessment across different scales from a federal state down to a parcel of land. The ‘parcel’ aggregation-level proves to be useful to assess the erosion risk. Larger scales are less useful in the assessment of subsidies policy with regard to erosion risk. A moving-window-technique combined with VERMOST is demonstrated to be suitable for comparing and assessing regional aspects more objectively compared with data administratively linked. [ABSTRACT FROM AUTHOR]

Climate change is expected to affect the occurrence of heavy rainfall. We analyzed trends of heavy rainfall days for the last decades in Germany. For all available stations with daily data, days exceeding daily thresholds (10, 20, 30 mm) were counted annually. The Mann–Kendall trend test was applied to overlapping periods of 30 years (1951–2019). This period was extended to 1901 for 111 stations. The stations were aggregated by natural regions to assess regional patterns. Impacts of data inconsistencies on the calculated trends were evaluated with the metadata and recent hourly data. Although the trend variability depended on the chosen exceedance threshold, a general long-term trend for the whole of Germany was consistently not evident. After 1951, stable positive trends occurred in the mountainous south and partly in the northern coastal region, while parts of Central Germany experienced negative trends. The frequent location shifts and the recent change in the time interval for daily rainfall could affect individual trends but were statistically insignificant for regional analyses. A case study supported that heavy rains became more erosive during the last 20 years. The results showed the merit of historical data for a better understanding of recent changes in heavy rainfall. [ABSTRACT FROM AUTHOR]