Spatiotemporal modeling of soil loss and sediment yield due to land use and land cover changes: implications for watershed management

Abstract

ABSTRACT Understanding the effects of land use and land cover (LULC) change on soil erosion and sedimentation holds significant importance in the context of watershed management planning. A comprehensive analysis was conducted in the Borkena watershed, spanning from 1993 to 2023, to investigate the impacts of LULC modifications on soil erosion and sediment yield. The methodology adopted in this examination involved the utilization of a hybrid land-use classification approach for the classification of Landsat images over time. Combination of the Revised Universal Soil Loss Equation method and Geographic Information System, incorporating variables such as rainfall erosivity, soil erodibility, slope length, steepness, cover management, and conservation techniques as input, was used to examine the effect of LULC changes on sediment yield and soil erosion trends. The outcomes revealed a notable expansion in cropland and urban areas, while natural vegetation cover like forest land and shrub land experienced a decline in the specified timeframe. Consequently, the mean annual soil erosion rate escalated from 25.5 t ha−1 year−1 in 1993 to 42.3 t ha−1 year−1 in 2023, with the sediment delivery ratio and sediment yield following similar increasing trends from 0.41 to 0.49 t ha−1 year−1 and 18.3 to 29.4 t ha−1 year−1, respectively.