三峡水库不同调度方式运行期洞庭湖区的水情响应

Responses of Water Regimes in Dongting Lake Area under Different Dispatching Modes during the Running Period of the Three Gorges Reservoir

运用1951-2002年典型年实测原型水文资料,对比分析2003-2010年三峡水库不同调度方式运行期对洞庭湖区水情的影响,结果表明:(1)影响时间为每年5月25日-6月10日、7月1日-8月31日、9月15日-10月31日、12月-次年4月,其中枯期补水调度的影响不很敏感;(2)预泄调度,平水年径流有所增加,平均水位、最高水位均有上升。丰、枯年影响期径流增加平均值40.25×108m3;平均水位抬高平均值1.06m,最高水位壅高平均值1.06m;(3)蓄洪调度,平水年洪水量稍有上涨,枯、丰年影响期洪水减少平均值444.02×108m3,平均洪水位降低平均值2.64m,最高洪水位降低平均值1.42m;(4)蓄水调度,除平水年影响期径流增加、水位稍有壅高外,枯、丰年影响期径流减少平均值185.27×108m3,平均水位降低平均值3.13m,最高水位降低平均值2.14m;(5)补水调度,平、丰年影响期径流减少平均值337.7×108m3,平均水位降低平均值1.89m,最高水位降低平均值2.39m,但枯水年影响期径流量增加、平均水位与最高水位稍有抬高。

Based on the field-survey hydrological data in typical years,the effect of different dispatching modes during the running periods of the Three Gorges Reservoir on water regimes in Dongting Lake area is comparatively analyzed.The results are shown as follows.1） The influence periods are from 25th May to 10th June,from 1st July to 31st August,from 15th September to 31st October and from December to the next April,among which the influence of the water-supplement dispatch in the dry season is not very sensitive.2） During the period under the pre-discharge dispatch,the runoff slightly increases as well as both the average and highest water levels rise in the usual year,while in the wet and dry years,the average increase in the runoff is 40.25 × 108 m3 and the average rises of the average and highest water levels are both 1.06 m.3） As for the flood-storage dispatch,the flood volume increases slightly in the usual years.In the dry and wet years,the flood volume,the average and highest flood water levels averagely reduce by 444.02 × 108 m3,2.64 m and 1.42 m respectively.4） Under the water-storage dispatch,the runoff slightly increases and the water level rises in a sort in the usual year.And in the dry and wet years,the average decreases in the runoff,the average water level and the highest water levels are respectively 185.27 × 108 m3,3.13 m and 2.14 m.5） During the period under the water-supplement dispatch,the runoff,the average water level and the highest water levels averagely decline by 337.7 × 108 m3,1.89 m and 2.39 m respectively in the usual and wet yeas.However,in the dry year,the runoff increases,and the average and highest water levels slightly go up.