中文摘要：

为更好开展南水北调中线工程对汉江中下游水华生态环境问题的量化研究，分析了调水工程对汉江中下游水质的影响。基于龙王庙断面的水质序列，假设污染物通量不变，推算调水后断面水质数据并评价其水质类别。结果表明，调水工程对汉江中下游水质有明显影响。调水后，无引江济汉工程情形下，各时期水质超标率均增加；有引江济汉工程补偿作用下，枯水期、丰水期的水质超标率降低，但仍大幅高于调水前，而平水期水质超标率低于调水前。调水后，有、无引江济汉工程两种情形下均枯水期水质超标率最大，这表明调水工程对枯水期的水质影响最明显。汉江水华暴发期集中在枯水期，调水工程对汉江中下游枯水期水质的影响必然对水华暴发起促进作用。

英文摘要：

The present article takes as its aim to provide our analysis of the effect of the mid-mute of the state south-to-north water-transfer project on the water quality of the Hanjiang River＇ s told-lower reach. Based on the water quality series of Longwangmiao section, its data has been collected on the MR-SNWTP, classified and calculated under the presumption that the pollutant index remains unchanged. The results of our analysis indicate that the water quality in the mid-lower reach of Hanjiang River should have been significantly affected as the resuh of the project construction. The pollutants to the water composition tend to somehow change with some of them exceeding the state water standard when the MR-SNWTP （no DWYRHR） increases a lot. It is inevitable for the water pollutants to change with the compensation of DWYRHR, that is to say, the inghca, percentage of the water pollutants in the high water passing period and lower water- passing period, and lower percentage of the water pollutants in the intermediate water passing period. However, the percentage of the pollutant to the water quality may fall off the state standard in lower water period. Thus, it indicates that the water diversion project may affect the water quality more seriously in lower water-passing period than any other periods. Since the outbreak of water bloom in Hanjiang River concentrates in the dry season, the deterioration of water quality during the lower water-carrying period will be highly likely to accelerate the outbreak of water bloom in Hanjiang River.