Abstract: From 1982 to 1989, we have studied the surface runoff amount and dynamics of various vegetation types in Guangxi by location comparative method.The results indicated that 1. There are great differences of surface runoffs among vegetative types. The surface runoff of grasshill was greater than that of coniferous forest, which was greater than that of broad-leaved forest or the mixed forest of coniferous forest and broad-leaved forest. The surface runoff coefficients in various vegetation in Guangxi, which have great differences, were Small, averaging 0.78%. The maximum could be 57 times greater than the minimum. 2. Seasonal dynamics of surface runoff was mainly restricted by seasonal distribution of rainfall, and the surface runoff of various vegetations was mainly dependent on the comprehensive effects of crown or plant community, litter layer and soil layer. THe study also showed a pattern of the comprehensive effects that mixed broad-leaved forest or the mixed forest of coniferous forest and broad-leaved forest > grasshill. In this paper, a regression model of surface runoff of yarious vegetation types to precipitation outside of the forest was estabished.

Key words: Vegetation type, Surface runoff, Season dynamics, Analysis of correlation