长江源区径流年内分配时程变化影响因子分析

Analysis of impacting factor on change of annual runoff distribution in head-water area of the Yangtze River

长江源区是长江水文循环的起始地,源区的水量、水质变化和人类不合理活动对水环境的影响将波及广大的下游地区。在气候变化和人类活动的影响下,长江源区河川径流没有发生显著趋势性变化,本文根据长江源区1956-2005年月径流资料和降水、气温、蒸发资料,采用主成分分析法、线性趋势分析法,研究影响径流年内分配的主要气候因子。结果表明:降水和水面蒸发是影响径流年内分配时程变化的主要因子,气温的影响相对小。

Head-water area of the Yangtze River is the start site of Yangtze river hydrologic cycle.The water volume,water quality change and human unreasonable activities will influence water environment and spread broad downstream regions.Under the influence of climate change and human activities,the runoff in head-water area didn＇t happen significant trend changes.According to the monthly runoff,precipitation,temperature and evaporation data in the Yangtze River head-water area from 1956 to 2005,using the principal component analysis and linear trend analysis methods,the paper researched the main climate factor of affecting the annual runoff distribution.The results showed that the precipitation and water evaporation were the main effect facfor for the annual runoff distribution,and the temperature influence was relatively small.