Reservoir sedimentation as a consequence of land use in the catchment

Abstract

Reservoir sedimentation is a very complex problem. Natural conditions and anthropogenic activities have strong influence on sedimentation intensity and hydrological processes, which is represented at the experimental watershed of the Dicina River, in Western Serbia. Reservoir of 340000 m3 was formed after construction of a 17 m high dam, in 1966. Sedimentation of the Velika Dicina reservoire was determined on the basis of a survey from October 1966 to October 2011, along longitudinal profile, 750 m upstream from the dam, with 15 cross section profiles (at a spacing of 50 m). Land use changes were analyzed on the basis of a comparison of watershed conditions in 1966 and 2012, using the CORINE methodology and the MapInfo software. Sediment yield of the area and intensity of erosion processes were estimated on the basis of the Erosion Potential Method (EPM). The hydrological conditions in 1966 and 2012 (after the performed Erosion and Torrent Control Works-ETCWs) were assessed on the basis of a historical overview of land use changes and their impact on computed maximal discharges. Total quantity of deposited sediment in the reservoir amounts to 18750 m3. Intensity of sedimentation has continuously been decreasing since 2002 as the consequence of land use changes, performed ETCWs and depopulation. The realization of restoration works contributed to a decrease in the annual yield of erosive material from Wa=16007 m3 to Wa=1930 m3. Presented are the comparative results of sediment tran-sport for ri-vers in Serbia, with catchment area smaller than 1000 km2.