Impacts of Land-Use, Land-Cover, and Climate Changes on Streamflow in the Upper Lufira Catchment, D.R. Congo

Abstract

Hydrological processes are often influenced by the changes in land use, land cover, and climatic variables that negatively or positively affect all the hydrological components. For the Upper Lufira catchment, the factors affecting runoff and its relationship with land use/cover are less known. Thus, this study aims to assess the impacts of climate change and LULC change on streamflow of the Upper Lufira catchment using the powerful Soil and Water Assessment Tool. This study required three categories of data: a set of historically available climate data from 1990 to 2013, spatial data (DEM, two land use/cover maps respectively for 2000 and 2010, and a soil map), and hydrometric data. The results showed that streamflow was affected by the changes in LULC and Climate between 1998 and 2013 mainly by reducing it. The changes were also observed for other hydrological components. Lateral flow, base flow, evapotranspiration, and Percolation increased while surface runoff, soil water content, and water yield decreased. In conclusion, anthropogenic activities do indeed have a significant impact on streamflow as well as on hydrological components in the Upper Lufira catchment. Thus, we have recommended careful control of all human activities in the catchment, mainly by regulating deforestation activities and improving reforestation activities in the context of catchment sustainable management.