湖南省水旱灾害与暴雨径流资源的调控

Flood & drought disaster and regulation of storm-runoff resources in Hunan Province

通过对湖南省1950～2002年水旱灾情、1954～1998年降水量的统计,结合流域自然条件和水利现状综合分析表明:湖南省山丘区水旱灾害交替演进日趋明显,洞庭湖区外洪内涝交织频繁,农村饮水困难人口数量不断增多。7～9月降水量占全年降水量的20%,而4～9月降水量占69%,且多以暴雨形式出现,这一降水特点是导致水安全问题的症结所在。因此,必须充分利用山区有利地形修筑拦蓄小型工程,全方位建设生态环境,挖掘水库群的防洪兴利潜力和提高大型水库的调度水平等措施,调控4～8月的暴雨径流,以减轻水旱灾害,满足供水、发电、航运等方面的需水要求。

Based on synthetic analysis of the statistics of the flood & drought disaster conditions from 1950 to 2002 and the rainfall amount from 1956 to 1988 and from 1954 to 1998 in Hunan Province in combination with natural conditions of drainage basins and the current situation of water conservancy,several conclusions can be drawn.The alternative evolution tendency of flood & drought in hilly areas of Hunan Province becomes more and more evident,the flooding outside of and waterlogging inside of Dongting Lake area alternate frequently,rural population who have difficulties in getting drinking water increases constantly.The rainfall from July to September only occupies 20% of the year's total,contrarily,rainfall from April to September occupies 69%, and precipitation most frequently occurs in the form of storm runoff.And this precipitation characteristic is the sticking point leading to the water security problems.So,it is necessary to take measures such as making full use of the favorable landform to construct small scale flood retention and storage projects,to rehabilitate eco environment in an all round way,to bring into play the potential of reservoir groups in flood prevention and water conservancy works constru ction,and to enhance the adjustment levels of large reservoirs so as to effectively regulate storm runoff from April to August,mitigate flood & drought disasters,at the same time,to satisfy the water demands for water supply,power generation,navigation,tourism and so on.