runoff intensity
3.Abstract: In accordance with the problems in the system of well storing rainfall at present,based on the experiments of artificial simulating rainfall,and assistance with the measures of natural rainfall,the relationships among the surface runoff yield,silt concentration,catching runoff efficiency and the material of surface,slope gradient,rainfall intensity are analysed systematically.Then,the best slope gradient and material of surface are chosen,in condition of which surface rainfall yield is the largest and silt concentration is the smallest.This is a beneficial study for the practical use of the rainwater catchment plot in furture.
4.The research for soil permeability and surface runoff in Huangjia-Er- cha small watershed in Xiji county, Ningxia, was done by means of arti- ficial precipitation and runoff-plot testing method,which showed that pri- mary factors affecting soil permeability are land utilization, slop, soil moisture, total porosity of soil and rain intensity.
6.Chinese fir, enclosing and tending forest, Costarica henryi, orchard and control (bare land) in Jianou, Fujian by establishment of runoff plot. We systemically discussed the distribution of precipitation, dynamics of soil erosion in different land-use types, the relation between soil and water losses and some rainfall characteristics, such as rainfall amount, intensity, duration and prophase rainfall.
