摘要
在一个面积为834km2的森林流域上,采用覆盖率和林木蓄积量作为森林植被影响降雨径流的两个量化指标,并划分了两个等级:(1)森林覆盖率≥60%且蓄积量≥5000m3/km2;(2)森林覆盖率<60%且蓄积量<5000m3/km2。在构造的模型中,根据森林植被的两个量化指标,分别选取了不同的参数。在产流量计算中,该模型采用了蓄满产流模拟技术,土壤蓄水量计算采用了二层模式,流域蓄水容量-面积分配曲线采用了指数函数形式,即a=1-eKP。在汇流计算中,采用了分水源的演算方法,其中地表水汇流采用了等流时线法与线性水库调蓄相结合的技术,地下水汇流采用了简化三角形法。经过对模拟计算结果进行比较,表明该模型不仅具有较好的精度,而且还能大致反映出两种不同森林植被条件对涵养水源、调节洪水的不同作用效果。该模型具有较强的实用性,能够为森林水文功能的深化研究起到借鉴作用。
In order to evaluate the impacts of forest vegetation on rainfall-runoff in a forest watershed in area of 834 km^2, two quantitative indexes of forest cover, cover ratio and timber volume were adopted, and they were divided into two grades ： （ 1 ） forest cover ratio ≥ 60% and timber volume ≥5000 （ m^3/km^2 ） ; （2） forest cover ratio 〈 60% and timber volume 〈 5000 （m^3/km^2）. Different parameters were selected in the proposed mode in accordance with the two quantitative indexes. The simulation technique of filled-up runoff generation was applied to the calculation of runoff, and the two-layer simulation of evapotranspiration was applied to the calculation of soil water storage in watershed. An exponential equation i.e. a = 1 -e^KP was proposed to describe the relationship between the water storage capacity and the relative filled-up area in watershed. The different runoff components were considered in order to calculate the flood hydrograph, therefore, two routing methods were utilized , namely, the technique of equal time line of flow with regulation of linear reservoir and the simplified triangle hydrograph were adopted for surface and underground runoff of concentration simulation respectively. Comparing the simulation results with the observed data indicates that the proposed model not only is high in accuracy, but also reflects the effects of the two different forest indexes on water conservation and the flood regulation on the whole. The model is practical and will play important rule in farther study of the forest hydrological function.
出处
《生态学报》
CAS
CSCD
北大核心
2008年第5期2372-2379,共8页
Acta Ecologica Sinica
基金
国家自然科学基金资助项目(49871019)
山东农业大学科技基金资助项目(23091)~~
关键词
流域
覆盖率
蓄积量
产流
汇流
watershed
cover ratio
timber volume
runoff generation
concentration
