Mapping soil erosion in the Da Dang river basin, Lam Dong province

Abstract

The Da Dang river basin, located in the Upper Part of Dong Nai River, plays a crucial role to protect water resources in the downstream parts. The purpose of this study is to assess and develop a soil erosion map in the Da Dang river basin by using the Revised Universal Soil Loss Equation (RUSLE) combined with remote sensing (RS) and Geographic Information System (GIS). The factors used in the RUSLE equation (R, K, LS, C, and P) were computed by using data obtained from local meteorological stations, topographic maps, soil surveys, and satellite images.

The data on water quality (TSS) of 75 surface water samples was deployed at 15 monitoring sites in the river basin in the period of 2012 – 2016, provided by DONRE of Lam Dong. The results showed that 14.41% of the basin area is subjected to a high erosion rate with an extent of 10 tons/ha/year or more. Furthermore, the study also indicated that TSS concentration has a closely correlation with land use practices and the the spatial distribution of soil erosion. These findings are essential information and practical implications for local authorities in formulating provincial planning policy for land use and the management practices of soil and water protection in the Da Dang river basin, a sensitively mountainous area, in the context of climate change.