Loss of topsoil and soil erosion by water in agricultural areas: A multi-criteria approach for various land use scenarios in the Western Carpathians using a SWAT model

Abstract

Erosion by water is a major problem in agricultural areas, especially in mountainous zones. In this context, the mass of detached soil clods is affected by surface run-off. In this paper, the utility of simulated data has been assessed toward various land use scenarios and soil erosion. The aim of the research was to model relevant management options in agriculture areas using spatial data. Long-term monitoring of sediment yield in top-soil loss dynamics models can be applied to evaluate the environmental effects of water pollution. In our study, we used data from 1995 to 2014 to analyze erosive events. The SWAT (Soil and Water Assessment Tool) was selected to assess the rill and inter-rill erosion. The investigations were carried out in an agricultural mountain catchment of the Mątny stream, located in the West Carpathians. Model calibration indices showed satisfactory adjustment of the model to the experimental data. Three scenarios of the catchment land use were distinguished (basic, first and second): the basic involved the actual structure of the land use, including a spring oat crop; in the first, the spring oat crop was replaced with potato crop; and in the second, it was assumed that the entire catchment area was covered by grassland. In the basic scenario, mean annual top-soil loss was 8.01 Mg ha−1, in the first it was 16.99 Mg ha−1, and in the second, 6.02 Mg ha−1. Thus, land management options can provide powerful constraints on predictions of sediment budget (Suspended Sediment Concentration). The management options simulated by SWAT model were important to effectively reduce top-soil loss in agricultural catchments.