ASSESSMENT OF THE IMPACT OF LAND USE CHANGES ON SURFACE WATER RESOURCES IN SE SAN RIVER BASIN

Abstract

Land use change is one of key factors that largely affect different components of hydrological processes both in space and time and subsequently alters river flows as well as surface water resources in different areas of the basin. Land use change is a continuous process and occurs at basin scale. Land use change leads to changes in the water flows and changes in water demand for different sectors in the basin leading to changes in surface flow regime as well as the surface water resources in the basin. This study assessed the impact of land use change on surface water resources in the Se San river basin. Results shows that the increase in forest planned for 2020 in comparision with the year 2015 leads to reduce water in flood season and increase in water in dry season in many areas, especially in the upper of the basin. The increase in non-agricultural land areas as well as in open water bodies have reduced water volume in the dry season and increased that during the flood season in some areas of the lower and middle basin.