Simulation and Evaluation of Different Vegetation Cover Scenarios Effects on Soil Erosion

The hillslope erosion is known as the first phase of soil erosion at watershed and the most important in semiarid region. Therefore, assessing effective factors on soil erosion and sediment yield such as land cover at hillslope scale can provide new information leading to more effective decision-making. However, very limited studies have been reported to assess the role of land cover on hydrology at hillslope scale using simulation model. The present study aimed to simulation and then analysis the affectability of soil erosion and sediment yield from land cover percentage scenarios at hillslope scale. For this purpose, Hillslope Erosion Model (HEM) was used for prediction of 16 storm related sediment yield in rangeland of Younesi research center, Markazi Providence. The results showed that HEM could successfully predict the soil erosion rate in study area by calibrating soil erodibility parameter with estimate error and CE of 44 and 88 percent, respectively. Then, effects of 3 scenarios i.e. 10%, 20% and 30% decreasing in rangeland cover were simulated using HEM after calibration and validation of the model. The results, also, showed that soil erosion increased about 21%, 45% and 82% in scenario 10%, 20% and 30% reduction of cover, respectively. Finally, results showed that vegetation cover density had significant effect on sediment yield at hillslope scale.