一、降雨径流特点海南岛年平均降水量1,725毫米,降水总量585亿立方米,但在时空分配上存在着年际不均、年内不均、地区不均三个基本特点:(1)年际降雨量分配不均,丰水年为枯水年的2.6～5.6倍;且常有连续几年丰水或枯水的特点.(2)年内降雨量分配不均,湿季降水量占年降水量的80～90%,干季降水量 I. Characteristics of Rainfall Runoff Hainan Island has an average annual rainfall of 1,725 ​​millimeters and a total precipitation of 58.5 billion cubic meters. However, there are three basic characteristics of uneven distribution in time and space: unevenness in the year and unevenness in the region: (1) year The distribution of inter-annual rainfall is uneven, and the wet years are 2.6 to 5.6 times of those in dry years. There are often abundant or low water characteristics for several years in a row. (2) The annual rainfall is unevenly distributed, Precipitation of 80 to 90%, dry season precipitation