四水入洞庭湖水量变化趋势及周期分析

Analysis on variation trends and cycle of water inflow from four rivers to Dongting Lake

为了解湖南四水入洞庭湖水量的现状和变化趋势，为水资源合理配置提供依据，以湘江、资水、沅水、澧水入洞庭湖的代表性控制站1960～2010年长系列水文数据为基础，采用肯德尔秩次趋势性显著检验法探讨了四水入洞庭湖的水量变化趋势，研究了水利工程对四水径流变化的影响及其原因。结果表明，四水年入湖水量在1960～2010年期间未见显著的增长或减少趋势；水利工程的修建对四水径流的年际变化影响较小，但对年内变化有一定影响；四水入湖水量作为一个系列具有2～3 a的短周期和12 a左右的长周期。

In order to master the status and variation trends of water inflow from the four rivers to Dongting Lake and provide basis for rational water resources allocation, based on the long series of hydrological data of representative controlling stations on Xiangjiang, Zishui, Yuanshui and Lishui rivers, by using Kendall rank test, the variation of water inflow to Dongting Lake and the influence of water resources projects on runoff variation of the four rivers and the variation causes are analyzed. The analysis results show that the incoming water from the four rivers has insignificant differences in the period of 1960 - 2010 ; the influence of water project construction on the inter- year variation of the four rivers is smaller, but larger on the runoff within a year; the runoff of four rivers into Dongting Lake has a short cycle of 2 - 3 years and a long cycle of about 12 years.