长武黄土高塬沟壑区降水及侵蚀性降雨特征

precipitation; erosive rainfall; Loess Plateau-gully Region; 【摘要】 利用长武县气象局1957—2006年的日降水量资料,分析该地区降水的年内、年际变化、概率分布特征等。结果表明:该区降水量季节分布不均,主要集中在7—9月;降水量的年际变化幅度较大,多年变化呈明显的丰水、平水、枯水年交替发生现象;降水量的年际变化大于年降水时间的年际变化。对侵蚀性降雨研究发现,其主要发生在7、8月,以降雨量小于30 mm的降雨次数较多;降雨强度随降雨量增加而减小;同时,以短历时降雨为主,历时在30min以内的降雨次数较多,其他时段相对较少。

The monthly and annual distribution characteristics of precipitation as well as the probability distribution of annual precipitation were studied,utilizing the daily precipitation from 1957 to 2006,data of which supplied by the Changwu Meteorological Station.The results demonstrate that the distribution of monthly precipitation is variable,and mainly concentrated in July,August,and September.The total annual precipitation varied greatly from year to year.The annual variation of precipitation is larger than ...