Preliminary Study on Hydrologic Function ofDifferently Structured Pinus yunnanensis Forestsin Central Yunnan Province
Liu Wenyao Liu Lunhui Zheng Zheng(Kunming Institute of Ecology, Chinese Academy of Sciences)
Canopy interception, soil erosion, water and nutrient conditions of soil and the water retaining capacity of litter, under differently structured Pinus yunnanensis forests in central Yunan Province were studied. The results showed significant differences of hydrologic function among three differently structured P, yunnanensis forests. In the multi-storeyed forest, the mean annual percentage of canopy interception was 13.4% of the rainfall and was 9.3% and 7.9% in the grass-P.yunnanensis forest and the open forest; maximum water retention was 65.8t/ha, 46.6t/ha and 6.7t/ha respectively, the mean annual soil losses were 0.015t/ha, 0.088t/ha and 0.452t/ha respectively, the mean annual surface water runoff were 4.32mm, 15.59mm and 85.57mm respectively, and the coefficients of surface runoff were 0.60%, 2.16% and 11.85% respectively. The soil water content and the content of organic matter, total N and available P, K in the surface soil of the open forest were lower than that of the other forests. From these results we can conclude that, to increase the hydrologic function of the forests, mixed forests of P,yunnanensis and of broad-leaved, multi-storeyed trees should be planted. Moreover,attention should be paid to protection of cover plants and litter.
【CateGory Index】： S715;;S791.257