A watershed, also called a drainage basin or catchment area, is defined as an area in which all water flowing into it goes to a common outlet. People and livestock are the integral part of watershed and their activities a/ect the productive status of watersheds and vice versa. From the hydrological point of view, the di/erent phases of hydrological cycle in a watershed are dependent on the various natural features and human activities. Watershed is not simply the hydrological unit but also socio-political-ecological entity which plays crucial role in determining food, social, and economical security and provides life support services to rural people" [6].

A watershed can be also understood as a

• hydrologic-response unit, a physical-biological unit, and a socioeconomic political unit for management planning;
• a smaller upstream catchment that is part of a river basin [7].