A model of the hydrological behaviour of the Zabarwan hillslope in the Kashmir Himalayan region

This study focused on the characterization of the hydrological response of a small hillslope region and the subsequent development of a model of the associated hydrological processes. The components of hydrological cycle remain more or less the same in almost all kinds of terrains. However, the redistribution of precipitation over hillslopes differs from that over moderate terrains in a number of ways. On hillslopes, non-horizontal water table and non-uniform soil saturation levels over the length of slope lead to simultaneous occurrence of infiltration and overland flow over different parts of the slope. Flow paths of a hillslope differ greatly in length, direction and response time; and the path taken by precipitation depends on the soil cover, slope and underlying geological setup. Moreover, the existence of preferential flow paths also modifies the hydrological response. Therefore, an attempt was carried out to model runoff generation processes on hillslopes keeping in view the above facts. The model was applied to simulate the hydrology of Zabarwan hillslope, a part of the catchment of the Dal Lake in India. The model could successfully capture the physically observed hydrological phenomena in the study area that include flow through macropores in the higher parts, and return flow and saturation upto the ground level at the foothills of the Zabarwan hillslope.