A tropical river discharge response to land cover change

Abstract

Abstract- River discharge is a function of land use land cover (LULC) among others within a given watershed. The watersheds in Kenya are rapidly changing due to the expansion and intensification of agriculture thus influencing river discharge. The study was conducted in Chepkaitit and Moiben Rivers watershed located along Trans Nzoia, Uasin Gishu and Elgeyo Marakwet counties in Kenya. The specific objective was to determine how change in LULC influences the river discharge under three scenarios of the current, 100% agriculture and 100% forest LULC. The LULC change analysis data used Landsat satellite imagery downloaded from USGS website while the SWAT model was used in river discharge analysis. The weather data was downloaded from “Global Weather data for SWAT” website and DEM (slope data) downloaded from USGS website while model output calibration used SWAT-CUP. The study also found out that changes in the LULC significantly influenced the river discharge with R2 of 0.96 at p = 0.00001 at a significant level of 0.05. The change in river discharge was more pronounced in April where scenario 2 river discharge varied by -28.51% and 19.57% for scenario 3. The study concluded that the significant changes in LULC influenced river discharge significantly with synchronized flow under forest cover.