Soil surface erosion susceptibility analysis using the USLE model. Case study: Bran - Dragoslavele Corridor, Romania

Abstract

The present study falls within the scope of the analysis of the morphodynamic potential of the Bran - Dragoslavele Corridor (Romania), a low mountain area, favorable to erosion processes due to the high energy of the relief, diversified lithology, tectonic complexity, and due to the variation in the energy of atmospheric risk phenomena. For the expansion of pastoral agricultural areas and those intended for human settlements, the deforestation of the last 3-4 centuries deprived the slopes and the soil of the protective forest cover on an area of 55.44%, favoring the amplification of the action of natural morphodynamic agents. In this context, the quantitative and spatial assessment of sheet erosion, expressed as the average annual rate of surface soil erosion (measured in tons hectare–1) was approached by applying the calculation model implemented in the GIS environment by using the universal soil loss equation (USLE). Implementation of the model was realized through the spatial delimitation of the potential erosion and the rendering by susceptibility classes of the quantitative results which reveal the fact that the largest surface of the studied mountain unit (91.68%) presents tolerable values, of 0-1.5 t ha–1 year–1. The highest values, over 4 t ha–1 year–1 (1.24%), are characteristic of the calcareous areas belonging to the many sectors of the gorges with discontinuous vegetation, as well as the limestone exploitation area from Mateiaș mountain. The quantitative knowledge and spatial distribution of surface erosion becomes important for communities and local authorities, interested in the planning and management of the implementation of some agrotechnical measures to improve the quality and productivity of soils or to prevent and restrict erosion processes with a tendency to expand areally and in depth.