基于Mann-Kendall法的汉江上游水沙趋势分析

为了解汉江上游水沙变化趋势以指导水利工程规划建设,利用汉江洋县水文站1956~2008年还原后的天然年径流和年输沙量序列,采用非参数检验Mann-Kendall法,分析了汉江洋县水文站天然径流和输沙量的年际年内变化趋势和发生突变的年份,以及引起天然水沙序列变化的主要影响因素。分析结果表明,1990年代以后,汉江上游的径流和输沙量发生减小突变,且减小趋势显著;径流量突变发生在1993年,突变前后偏小的幅度为40%;泥沙量突变发生在1990年,突变前后偏小的幅度为85%。研究结果为流域的防洪治理、河道整治、水资源规划等提供了科学依据。

Trend Analysis of Flow and Sediment in Upstream of Hanjiang Basin Based on Mann-Kendall Test Method

In order to understand the change trend of water and sediment in the upper reach of the Hanjiang River to guide the planning and construction of water conservancy projects, the intra-annual & inter-annual variation trend of natural runoff and sediment discharge as well as abrupt change point years in the Yangxian hydrologic station, together with the main factors influencing natural water and sediment sequence changes were studied with the Mann-Kendall method, based on the restored natural runoff and sediment discharge sequence from 1956 to 2008. The results show that the runoff and sediment in the upper reach of the Hanjiang River present an abrupt change and the decreasing trend is obvious after 1990. The sudden change of runoff occurred in 1993 with the magnitude of 40%, and the abrupt change of sediment occurred in 1990 with the magnitude of 85%. The research results provide scientific basis for the protection of the river basin, the river regulation, the planning of water resources and so on.