以西、北、东江控制性水文站1959-2010年共52年的实测水文资料为基础,运用Mann-Kendall法、集中程度等方法分析了西、北、东江的水资源特性。结果表明:(1)西、北、东江径流量有明显的丰枯变化,长系列呈下降趋势,西、北、东江径流量不同年代年平均径流量有明显的差异;(2)西江径流量在1968-1987年和1997-2003年具有上升趋势,其他时段具有下降趋势;北江径流量在1996-2008年具有上升趋势,在1963-1974年和1986-1994年具有下降趋势;东江径流量在1976-1988年具有上升趋势,在1959-1975年和1989-1996年具有下降趋势;变化趋势都没有通过95%的置信度检验,上升或下降趋势不显著。(3)西、北、东江径流量的年内变化在不同时间段存在差异性,20世纪60年代以来,西江、北江径流量年内分配不均匀性较东江径流量年内分配不均匀性大;东江径流量年内分配具有明显均匀化趋势,东江年最小流量占年平均径流量比值有较明显增加趋势,有利于水资源的开发利用。
Based on the measured hydrological data of controlled hydrological station of the West River, the North River and the East River from 1959 to 2010, the Mann-Kendall method and the degree of concentration are used to analyze the characteristics of water resources of the rivers. The results show that : (1) The runoff of the West River, the North River and the East River has obvious wet and dry water changes, the long series of runoff have decreasing trends, and the annual runoff is different in different ages. (2) The runoff of the West River had a rising tendency in 1968-1987 and 1997-2003, which had a decreasing tendency in other times. The runoff of the North River had a rising tendency in 1996-2008, which had a decreasing tendency in 1963-1974 and 1986- 1994. The runoff of the East River had a increasing tendency from 1976 to 1988, which has a decreasing tendency in 1959-1975 and 1989-1996. The trends of changes have not passed the 95% confidence test, the increase and decrease are not significant. (3) It is different that the variation of runoff in a year of the West River, the North River and the East River at different time intervals since 1960s. It is larger that the uneven distribution during the year of runoff of the West River, the North River than the East River. The distribution during a year of runoff becomes obviously homogenized. The ratio of annual minimum runoff to annual average runoff of the East River has obvious increasing tendency, which is favorable to the development and utilization of water resources.