基于日雨量的降雨侵蚀力模型研究

降水是导致水土流失的主要动力因素之一,降雨侵蚀力反映了降雨对土壤侵蚀的潜在能力。目前,国内外许多学者正在研究降雨侵蚀力的简易算法,其中利用日降雨资料来估算降雨侵蚀力是目前精度较高的一种估算方法。利用湖北省大别山山区黄冈地区水土保持试验站1961~1971年以及1983~1991年20 a逐日降雨过程资料重点分析了研究地区的降雨侵蚀力季节和年际分布特征,并分别采用三种日雨量模型模拟研究区域的降雨侵蚀力。研究表明,湖北省黄冈地区的降雨侵蚀力集中分布在4~10月,高峰值出现在7月,可占到全年R值的27.27%。基于日降雨的月降雨侵蚀力模型Ⅱ、Ⅲ,其决定系数达到0.921,平均偏差分别为1.15%和0.99%,与现有模型相比,模拟精度较高,具有实践意义。

Research of Rainfall Erosive Agent Models Based on Daily Rainfall

Rainfall is one of the main factors leading to soil erosion,the rainfall erosive agent reflects the rainfall potential for soil erosion.Currently,many domestic and foreign scholars are studying the simple algorithm to calculate the rainfall erosive agent,and the one using the daily rainfall information has a higher precision in estimating the rainfall erosive agent.In this study the 20 a(1961～1971 and 1983～1991) daily rainfall information of Soil and Water Conservation Experiment Station in Huanggang of Hubei is used to analyse the seasonal and inter-annual distribution of the rainfall erosive agent,three models are used to simulate the regional rainfall erosive agent.The research shows that the rainfall erosive agent in Huanggang of Hubei is distributed in April-October,the peaks in July,accounting for 27.27% of the annual value of R.The rainfall erosive agent Model II,III based on the daily rainfall have the decision coefficient of 0.921,with an average error of 1.15% and 0.99% respectively.Compared with the existing models,the models have a higher simulation accuracy and practical significance.