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本文研究了四川丘陵农区不同森林复盖率的水文效应,其结果为:1、森林复盖率58.5％的水文效应优于复盖率23.1％,后者的年迳流量为35.9—48.9万米~3;洪水期输沙量为156.2T/KM~2.Y,占年输沙总量的99.0％,常水位期与枯水位期输沙量仅为0.60T/KM~2.Y。2、据调查测定水库区,森林复盖率10—26％左右的来水含沙量0.85％,与农田水利设计要求水库工程设计来水限制含沙量0.7％相比仅差0.15％,但森林复盖率27％以上来水含沙量仅0.30％。经综合分析认为:四川丘陵农区森林复盖率25％左右,基本上能发挥森林的蓄水保土作用。
This paper studied the hydrological effects of different forest coverage in hilly areas of Sichuan Province. The results were as follows: 1. The hydrological effect of forest cover rate of 58.5% was better than the coverage rate of 23.1%, and the annual flow rate of the latter was 35.9-48.9 million M ~ 3. During the flood period, the sediment transport volume was 156.2T / KM ~ 2.Y, accounting for 99.0% of the total annual sediment transport. The sediment discharge in the normal and dry periods was only 0.60T / KM ~ 2.Y. 2. According to the investigation and determination of the reservoir area, the water sediment concentration of about 10-26% of the forest coverage rate is 0.85%, which is only 0.15% less than the limit of 0.7% of the water content of the dam design for the farmland water conservancy design Forest coverage rate of 27% above water sediment concentration of only 0.30%. After a comprehensive analysis, it is thought that the coverage of forests in the hilly and rural areas in Sichuan is about 25%, basically playing the role of water and soil conservation of forests.