Assessment of hydrological response as a function of LULC change and climatic variability in the catchment of the Wular Lake, J&K, using geospatial technique

Abstract

The present study aims to identify the relationship and effect of various hydrological processes on the Wular Lake ecosystem. The study focused on assessment of combined hydrological response of LULC change and climatic variability in the upper catchment of Wular Lake. Multi-temporal satellite data were used for assessment of temporal dynamics of the lake catchment. The spatiotemporal pattern of annual soil loss and sediment yield has been assessed using the Revised Universal Soil Loss Equation approach and sediment delivery ratio adopted from USDA Soil Conservation Service in GIS environment. The runoff was estimated in the watershed using SCS curve number. The main impelling forces that led to the changes in land use/land cover in the catchment is mainly due to increased human activities, which ultimately leads to the increased erosion and sediment yield. The anticipated mean annual soil loss which was found 123.23 t ha−1 year−1 in the year 1992 increased to 942.52 t ha−1 year−1 in the year 2013. Similarly, estimated mean annual sediment yield also indicated an increase from 34.7 t ha−1 year−1 in the year 1992 to 233.4 t ha−1 year−1 in the year 2013. In addition, the decrease in rainfall from the last 35 years has led to the decline in runoff and consequent reduction in the surface water supply. The results of the present study indicate due to the changes in LULC and consequent hydrological changes like decreased runoff, increased erosion and sedimentation reduce the water holding capacity of lake day by day, thus leading to its deterioration.