泥石流流域产沙与其他流域产流产沙不同，有其独特的特点。以云南东川蒋家沟为例，研究人工降雨下的小坡面产流产沙，自然降雨下的大坡面产流产沙，降雨的流域无泥石流时产流产沙和降雨的流域有泥石流时产流产沙，给出了相应的计算公式，并分别对比了各种情况下产流和产沙实测值与计算值，取得了较好的结果。

The runoff and sediment of debris flow catchment are different with other catchment. The experiments on slope with artificial rainfall, the observations on the slope innatural rainfall, the observations on the output of catchment and the observations on the output of debris flow had been analyzed. From the data of measurement in these experiments and observations, the different formulas of runoff and sediment were obtained. They are in different style and agree with the different data by measurement reasonable.