Abstract

Forest patterns of Qiaozi Eastern watershed and Qiaozi Western watershed in the Loess Hill-gully region of China in 1985, 1993, 2000 were analyzed using 9 parameters of landscape pattern. The changes of runoff coefficient of flood, depth of runoff and peak discharge modulus in these two watersheds also were analyzed using materials of precipitation and runoff in these watersheds. On the other hand, the relationship of forest pattern and flood runoff modulus in watersheds was established. The research results shows that with the increase of forest area, the flood runoff and peak discharge in watershed decrease at same time in same precipitation condition. The function that forest weaks flood runoff is obvious with reduce of connectivity and complexity and increase of adjacency.

Keywords: Watershed, flood runoff, forest pattern, response