Appraisal of Sediment Load in Rainfed Areas of Pothwar Region in Pakistan
Inadequate watershed management, natural, and man induced erosion of soils in the barani areas have threatened the sustainability of soil and water resources. In this study, sediment loads in the main streams passing through rainfed areas of the Pothwar region has been estimated for verifying the impacts of projects being implemented for agricultural development in the regions, especially the construction of small dams. The study has been carried out in three major basins namely Soan, Kanshi and Haro of Pothwar region. The daily discharge, sediment and rainfall data for the period 1982-2004 were analyzed and correlated accordingly. The sediment load has increased with the increase of river flow and vice versa. The unit rate of sediment yield decreased as the drainage area increased. Moreover, the observed sediment concentrations were low in low rainfall areas (Dhok Pathan) and high in areas fall under high rainfall zone (Chirah and Rawalpindi). Generally, the sediment concentration waslow during January to June (low rainfall) and high during months of October to December (high rainfall). The study concluded that sediment load beyond sustainable limits can affect the land and water resources negatively which can be identified by exploring basin hydrology and predicting sediment load as well as mitigating potential threats through application of computer simulation model.
