南水北调中线工程调水前汉江水文特性及变化

摘要

To evaluate the characteristics and change trend of hydrological features of the middle lower Hanjiang River before the water diversion of Middle Route of South-to-North Water Diversion Project, the long term data at 4 hydrologic stations and 18 meteorological stations on the mainstream were selected and the mathematical statistics, Mann-Kendall test and Spearman test were used. The results show that the rainfall in most regions of the basin has no noticeable changes while the temperature has obvious rise trend. The average annual runoff from 1999 to 2013 is reduced compared with that from 1956 to 1998, however, there is no obvious trend. Several changing periods of dry-wet years occurred from 1956 to 2013, among which, the period from 1992 to 2002 was the successive dry year and the period from 2002 to 2013 was the wet year in general.%基于汉江干流的4个水文站及18个国家气象站的长序列观测资料,采用数理统计、Mann-Kendall检验和Spearman秩次检验法,对南水北调中线工程调水前汉江流域水文特性及变化趋势进行了分析. 研究结果表明:汉江流域大部分地区的降雨无明显变化趋势;气温有显著升高趋势. 4个水文站1999~2013年年径流量多年平均值较1956~1998 年序列均有了不同程度的减小,但总体上无趋势性减小和增加规律. 1956 ~2013年间汉江流域径流经历了多次丰枯变化期,其中1992~2002年间为连续枯水期,2002年以后径流总体偏丰.