Abstract:

The Dongting Lake Region locates between the Yangtze River and the Sishui Rivers containing the Xiang,Zi,Yuan and Li River.Although being relatively wealthy in water resources,the region has been suffering from drought and waterlog constantly under the dual impacts of climate change and human activities,with a rising risk of water shortage.In order to discuss the impacts of upper large water projects (the Three Gorges Project and large water projects in the Sishui Basin) on water resources utilization in the Dongting Lake Region and distinguish it from other affecting factors,the intraannual and interannual characteristics of water level and runoff in the Dongting Lake as well as the Yangtze River and the Sishui rivers have been analyzed by dividing the study period into various sections,which can be used as a necessary support of the further water planning and development.Results indicated that the Three Gorges Project had exerted a certain negative impact on water utilization in the region in the initial phase of its builtup,mainly in the Sankou Region,while the impact of projects in the Sishui Basin appeared unnoticeable