黑龙江省降雨侵蚀力空间分布规律

Spatial distribution of rainfall erosivity in Heilongjiang Province

利用黑龙江省16个国家级气象站，1960-2000年日降雨量资料，分析黑龙江省侵蚀性降雨和降雨侵蚀力的空间分布规律。在16个气象站中，日降雨量达到侵蚀性标准（≥12mm／d）的降雨时间为9～15d／a，最大值同最小值之间相差近0．7倍；日降雨量达到侵蚀性标准的年降雨量为192～387mm，最大值同最小值之间相差l倍。16个气象站年降雨侵蚀力多年平均值为794～2144MJ·mm／（hm^2·h·a），最大值同最小值之间相差近2倍。降雨侵蚀力空间分布从西北到中南部逐渐升高，东部低于中部，年降雨侵蚀力空间分布基本与年降雨量空间分布相似。年内降雨侵蚀力分布主要集中在6—9月，7月份下半月或8月份上半月达到最高值，6—9月降雨侵蚀力占全年比率为88％～95％，其中西部比东部略高。

The spatial distribution of rainfall erosivity and erosive rainfall in Heilongjiang Province was studied, based on the daily rainfall data of 16 weather stations during the period from 1960 to 2000. Among the 16 weather stations, the average annual erosive rainfall frequency is between 9 and 15 days, and annual rainfall amount above with daily rainfall above erosive threshold is between 192 mm and 387 mm. Average annual rainfall erosivity （R factor） is between 794 and 2 144 MJ.mm/（hm^2.h.a）. Rainfall erosivity is mainly concentrated in June to September , and reach its highest value at later July or begin of August. The total rainfall erosivity in June to September is about 88 % to 95 % of annual value.