长江防护林(四川段)初期水土保持效益研究

Study on the Initial Soil and Water Conservation Benefits of Yangtiz River Protective Forest

该文重点研究了新造防护林前5年的防护效益。结果林冠截留系数可达19％，地表径流系数比荒地减小10％至19％，土壤蓄水能力比荒地提高90％。造林第3年产沙量减少至造林前的03至0．9，第5年时仅为造林前的0．1至0．3。同时防护林效益将随林龄增加而增长。

The initial 5-years benefits of newly built protective forest are studied in this paper. The results show that the canopy interception coefficient is up to 19%,runoff rate ofoverland flow decreases by 10~19% and the soil water storage capacity increases 90% than slope wasteland in the early two years. The annuaI sediment yield is decreases 10~70% in the third year and will be up to 70~90% in the fifth year after the protective forest has been built. At the same time,the benefits of protective forest will increase along with forest age prolonging.