Impacts of Land Use and Cover Changes on Water Balance in River Basin

Abstract

It is well known that there are huge land use and land cover changes (LUCC) all over the world in recent decades, and plenty of instable effect appeared on the energy and water balance. This study aims to analyze the impacts of land use and land cover changes on the energy and water balance in the Heihe River Basin of China during 2000–2010, and four key study sites with representative hydrological stations and dramatic LUCC in the past decades were selected to illustrate the responses of the energy and water balance to LUCC. First, LUCC of the Heihe River Basin from 2000 to 2010 was analyzed based on the interpretation of remote sensing images. Then a series of indicators of the energy and water balances were simulated with the Weather Research and Forecasting (WRF) model and corresponding land use and land cover data. Thereafter the impacts of LUCC on the surface energy and water balance were detected and analyzed. The spatial–temporal variance of the impacts of LUCC on energy and water balance in a typical arid inland river basin was specifically presented in the following analysis. The land use conversions can lead to the fluctuation of energy balance, and among those changes, the most significant impacts on surface energy balance occurred when grassland was converted to barren or sparsely vegetated land. As for water balance, the impact is measured with variations of precipitation, runoff, and evapotranspiration induced by LUCC, which were also remarkable, although seasonal trends of the effects are similar among various land use/cover conversions during 2000–2010. At last, policy suggestions, e.g., shifting the water balance by LUCC to improve the water management, are given to conclude this study.