Rainfall-Interception Effect of Vegetation Restored Region of Gully in Arid-Hot Valley of Jinshajiang River

摘要

This paper divides the process of rainfall redistribution into four levels in vegetation restored region of gully in arid-hot valley of Jinshajiang River. These levels include arbor interception, litter interception, soil interception and surface runoff. The results showed that the maximum of interception was 8.10 mm, the mean interception was 4.53 mm, the maximum of interception rate was 56.10 % and the mean interception rate was 32.63 %.When the rainfall is over 20 mm, the interception rate descends rapidly along with the rainfall increasing. The maximum of water-holding content of litter was 8.14-20.33 t/hm super(2), the mean of which is 12.52 t/hm super(2) and the maximum of water-holding content was over two times of it own weight. The rainfall of litter interception was 150.24 mm, accounted for the rainfall income 24.48%.The maximum water-holding capacity of soil achieves 2 198.54 t/hm super(2), but that of the barren land is 1 825.60 t/hm super(2). The rainfall of soil interception was 219.87 mm, accounted for the rainfall income 35.82%. The surface runoff of vegetation restored region was 43.41 mm, accounted for 7.07% of the rainfall income, but the surface runoff of non-forest land was 413.24 mm, accounts for 70.26% of the rainfall income. The surface runoff of the planted forest community was by 63.19% lower than that of the non-forest land. Through the interception of the forest land that reduced the soil erosion effectively, good hydrology effect was obtained.