【摘要】 洞庭湖枯水期面临的持续低水位对湖区生态环境带来严重影响,三峡水库枯水期增加下泄流量为洞庭湖生态补水提供了有利条件。为定量描述三峡水库枯水期不同运行方式对洞庭湖生态补水效果的空间差异,拟定3种水库典型消落方案,即提前消落、均匀消落、高水位消落;依托构建的江湖一体化耦合水动力模型分析不同消落方式对洞庭湖补水效果的空间分布格局,并评估不同方案对发电量的影响。结果表明:提前消落和高水位消落方式对洞庭湖水位的影响具有明显的空间异质性,对东洞庭湖北部影响较为明显,而对于东洞庭湖南部、南洞庭湖和西洞庭湖影响较小;提前消落较均匀消落方式城陵矶水位平均提高0. 12 m,对应的三峡发电量减小0. 30%,而高水位消落方式城陵矶水位平均降低0. 09 m,发电量增加0. 28%。研究成果可为兼顾洞庭湖生态补水的三峡水库消落方案的制定提供参考。更多还原

【Abstract】 The extremely low water level of the Dongting Lake during the dry season has a serious impact on the ecological environment of the Lake. The Three Gorges Reservoir( TGR) has increased the discharge for the lake to supplement water during the dry seasons. In order to quantitatively describe the spatial difference of water supplement effect on the ecological water supplement from the operation schemes of TGR at dry seasons,three typical schemes were proposed,namely,drop in advance,uniformly drop,and drop at high water level. Based on the integrated couplling mathematical model of rivers and lakes,the spatial distribution of Dongting Lake water level under different schemes was analyzed,and the impact of different schemes on power generation was evaluated. The results showed that the influence of drop in advance and drop at high water level on the water level of Dongting Lake had obvious spatial heterogeneity,and the influence on the northern part of East Dongting Lake was obvious,whereas for the south and west Dongting lake was small.The water level of Chenglingji increased 0. 12 m on average,and the power generation of Three Gorges power reduced 0. 30% for the drop in advance,while for the drop at high water level the water level of Chenglingji reduced 0. 09 m on average,and the power generation increased 0. 28%. The research results could provide beneficial reference for the formulation of the Three Gorges Reservoir’s drop mode taking into account the ecological water supply of the Dongting Lake.更多还原