浙江红壤区降雨侵蚀力季节分布与日雨量模型研究

Study on Temporal Distribution of Rainfall Erosivity and Daily rainfall Erosivity Model in Red Soil Area of Zhejiang

利用兰溪水保站的自记与常规雨量资料对降雨侵蚀力 R的季节分布进行了分析 ,并建立了一个降雨侵蚀力的日降雨量模型。结果表明 ,该地区降雨侵蚀力呈明显的单峰型季节分布 ,主要集中在 3～ 9月 ,其 R值占全年R值的累计百分比为 94 .5 % ,高峰期在 6月份 ,其 R值占全年 R值的 2 8.2 %。降雨侵蚀力的日雨量模型为 :Rj=0 .0 0 4 3 [1+ 4 8.13 sin(π/12 ( j- 1) ) ]ΣNk=1 P1 .0 9k 。本模型利用日降雨量计算降雨侵蚀力 ,有效系数为 0 .89,R值季节分布的预测值与实际值的平均偏差为 1.2 %。与国内现有模型相比 ,本模型能够较好地描述 R值的季节分布。

Pluviograph data at Lanxi soil and water conservation experiment station in the Zhejiang were used to compute the rainfall and runoff factor (R factor) for the Universal Soil Loss Equation (USLE), and rainfall erosivity model using daily rainfall amounts to estimate rainfall erosivity was validated. The distribution of rainfall erosivity are highly seasonal with a single peak in June. Summer months (3～9) typically contribute 94.5% of the R factor. The daily model could adequately describe the temporal variation and seasonal distribution of rainfall erosivity. The coefficient of determination of model is 0.89.