单位降雨 meaning in English

unit rain
unit storm

Topography fractal dimension related with process of development of watershed physiognomy and represented degree of watershed development , v ) sediment yield intensity of watershed model reflected erosion characteristic of watershed model in different development phase . simulating experiment indicated that sediment yield intensity took on the trend that they changed from small to big then decreased gradually . the relationship of average sediment transport rate and sediment yield rate per mm rainfall with topography fractal demension is expressed by gaussian model and this model is similar with relationship between volume and surface area
( 5 )流域模型产沙强度的变化反映了流域模型在不同发育阶段的侵蚀特征，模拟试验研究结果表明：在整个流域模型地貌地貌的发育过程中，其产沙强度呈现由小到大，然后又逐渐减小的总体趋势，流域模型单位降雨产沙率及平均输沙率与地形分维数表现为gaussian模型关系，其关系形式与结论3中相对体积和表面积之间关系相似，进一步说明了以地形分维数表达地形变化的合理性。