SWAT 모형을 활용한 아프가니스탄 살람 댐의 유출 및 퇴적물 추정

Sediments are a principal component in water resource projects for dam sedimentation, soil and water conservation, and design of efficient erosion control structures. High sediment rates lead to filling dam and loss of live storage of dam, which is eventually commanding to loss of production potential and evacuation of sediments from the dam is a costly process that can have large environmental impacts. A physically-based distributed hydrological model, SWAT (Soil and Water Assessment Tool), was used to estimate of runoff and sediment yield in the outlet of Salma Dam watershed in Harirud river basin measuring of 11,550 km2 catchment area. The main objectives of the study were to analyze the sediment yield in the outlet of the catchment and effect of LULC (Land Use and Land Cover) changes on sediment yield and flow values. The basin shows large heterogeneity in term of a hydrogeological parameter, LULC and soil features. The model was calibrated and validated using observed runoff and sediment yield data of 10 years (2008-2018) at the basin outlet. The average values for RSR (RMSE-observations standard deviation ratio) and NSE (Nash- Sutcliffe efficiency) for sediment are found to be 0.60 and 0.61, for runoff are found to be 0.67 and 0.64, which are within good limits for sediment and a good limit for runoff respectively. The overall average annual output for sediment at the outlet point was estimated 133.02 Met ton/month, is model monthly output. In general, the model was capable of simulating runoff and sediment in Salam dam watershed. As land development is a continuous process, for the optimum use of the land cover and water resources of the area, it is recommended that soil and watershed conservation practice should be undertaken in order to keep the sustainability of the reservoir conserving sediment reduction.