【摘要】 降雨侵蚀力反映了雨滴击溅和降雨产生的径流对土壤的侵蚀能力,侵蚀性降雨标准可以将引起侵蚀和不引起侵蚀的降雨区分开来,该标准的确定可以大量减少计算降雨侵蚀力的工作量。利用北京密云石匣水土保持实验站坡耕地小区和休闲地小区10年的降雨径流泥沙观测资料,分析了不同大小样本序列下的侵蚀性降雨的降雨量标准。结果表明,样本数达到7年时,所拟定的降雨量标准才能稳定。确定了北京的侵蚀性降雨的雨量标准和最大30min雨强标准,分别为18.9mm和17.8mm/h,该研究结果可为北京山区土壤侵蚀预报参数的计算提供依据。更多还原

【Abstract】 Rainfall is an important factor in causing soil erosion,and its ability to cause soil erosion is referred to as rainfall erosivity.Determination of a practical threshold for separating erosive and non-erosive rainfall events can reduce the amount of work necessary to calculate rainfall erosivty.In this study,10 years rainfall and sediment data at Miyun water and soil conservation station in Beijing were used to analyze the effects of sample size on the threshold of erosive rainfall standard and determine erosive rainfall standard.The results showed that a sample of 7-year could satisfy the requirements of obtaining a stable erosive rainfall standard.Rainfall amount standard and 30-minute maximum rainfall intensity standard of erosive rainfall event were 18.9 mm and 17.8 mm/h,respectively.This result can serve the soil loss prediction and water and soil resource management in Beijing mountainous area.更多还原