摘要
三峡工程建成投入运行后,汛末蓄水将使坝下河湖水情发生变化,长江中下游秋季来水减少成为常态.为客观分析三峡蓄水对洞庭湖水情的影响分量、空间格局及其作用机制,选取三峡工程典型的蓄水过程,运用长江中游江湖耦合水动力学模型计算了因上游来水变化引起的洞庭湖水情时空变化.结果表明:1)三峡汛末蓄水对洞庭湖水位影响具有明显的"北高南低,东强西弱"的格局,即东洞庭湖最为显著、南洞庭湖东部和西洞庭湖北部次之,南洞庭湖西部和西洞庭湖南部最小.2)洲滩湿地受蓄水影响最明显的主要为东洞庭湖、南洞庭湖和湖泊洪道两侧的条带状洲滩.3)三峡蓄水对洞庭湖水位的影响机制有二:长江干流水位快速消落加速湖泊水体下泄以及削减长江三口分流补给湖泊的水量.
With the operation of Three Gorges Project（TGP）,water regime of rivers and lakes downstream of the dam changed with the reservoir regulation.The lowering of water level becomes normal after flood season compared with the years before TGP.Here,the water storage of TGP in 2006 was selected as a case to quantitatively investigate the effects of TGP on water regime of Lake Dongting.We applied the coupled hydrodynamic analysis model for the middle Yangtze River to compute the variation of water regime induced by the water storage.During impoundment,the reduction of the water level and discharge are 1.32m and 466m3/s,respectively,at Chenglingji,the outlet of Lake Dongting.The bottomlands inside the Lake Dongting are exposed ahead of time and the lake area with over 5 inundation days reach to 287 km2.Results also indicate that： 1） the impact of TGP on water regime varied with locations： east Lake Dongting takes the first place,the east of South Lake Dongting and the north of West Lake Dongting second,and the west of South Lake Dongting and the south of West Lake Dongting third.2） The bottomlands which strongly affected by the impoundment are mainly located at East Lake Dongting,South Lake Dongting and the both sides of flood ways.3） Two influencing mechanisms on water regime are identified： one is the increase of the lake discharge induced by the rapid drawdown of the mainstream of the Yangtze River;the other is the reduction of inflow from the Yangtze River via Sankou distributary channels.
出处
《湖泊科学》
EI
CAS
CSCD
北大核心
2012年第2期178-184,共7页
Journal of Lake Sciences
基金
国家重点基础研究发展计划项目(2012CB417000)
中国科学院知识创新工程重要方向项目(KZCX1-YW-08-01)
国家自然科学基金项目(41071021)联合资助
关键词
三峡工程
蓄水
水情
淹水历时
水动力学模型
洞庭湖
Lake Yuxingze
the lake-appearance stratum
natural flood detention area
the Tribute of Yu（Yugong）
