Effects of land-use and land-cover change on evapotranspiration and water yield in China during 1900-2000

摘要: China has experienced a rapid land-use/cover change (LUCC) during the 20th Century, and this process is expected to continue in future. How LUCC affected water resources across China, however, remains uncertain due complexity of LUCC-water interactions. In study, we used an integrated Dynamic Land Ecosystem Model (DLEM) conjunction with spatial data estimate effects on magnitude, temporal variations evapotranspiration (ET), runoff, yield China. Through comparisons DLEM results other model simulations, field observations, river discharge data, found that can adequately catch seasonal patterns hydrological processes. Our simulation demonstrate led substantial changes ET, most China's basins Century. The varied significantly largest occurred second half century when almost all had decreasing trend ET increasing contrast inclinations declinations major basins, such as Pearl basin, Yangtze Yellow basin first century. increased runoff indicated alleviated deficiency late but peak flow might make difficult be held by reservoirs. continuously Continental Southwest Songhua Liaohe implied regional deficiency. study indicates deforestation averagely 138 mm/year decreased same amount reforestation 422 since deforested land was converted paddy or irrigated cropland. cropland-related transformation dominant anthropogenic force affecting On national average, cropland expansion estimated increase 182 while abandonment 379 mm/year. indicate urban sprawl generally yield. Cropland managements (fertilization irrigation) 98 To better understand resources, it needed take into account interactions environmental climate atmospheric composition. © 2008 American Water Resources Association.