Effect of Land Use Change Scenarios on Soil Erosion in Gharesoo Watershed

Soil erosion is a result of the interaction between nature and human activities. Soil erosion is one of the major problems that threatens sustainability of natural resources. The assessment of soil erosion using empirical-based models has long been an active research topic. Revised Universal Soil Loss Equation (RUSLE) is possibly the most widely applied and accepted empirical erosion model worldwide. The RUSLE model has been extensively applied for estimating erosion rates based on five parameters (rainfall, soil, topography and slope, land cover, and support practice). The C-factor (land cover) represents the characteristics of soil management and cover in RUSLE and is highly correlated to the land use/land cover practice We analyzed changes in land cover to estimate a future scenario for 2047 using an artificial neural network. The C-factor values were assigned based on historical land use maps. Soil erosion variations in the years 1984, 2008, 2017 and 2047 were estimated using the RUSLE model based on the land use scenarios. The mean soil erosion rates based on the land use scenarios were 21 t/km2/y (1984), 23.9 t/km2/y (2008), 24.6 t/km2/y (2017), and 27.3 t/km2/y (2047). The results showed that the sub-basins 5, 8 and 11 were the third top areas contributing to the increased erosion rate in all years.