5种主要森林类型涵养水源能力比较研究

从林冠层、凋落物层及土壤层3个生态作用层次对三峡库区莲峡河小流域5种主要森林类型的涵养水源功能进行了定量研究 结果表明: 林内透雨量、树干径流量与降雨量、降雨强度呈二元线性关系; 林冠截留量与降雨量呈幂函数关系 林冠截留率为16 34%~27 43%, 平均为22 15%, 依次为针阔混交林>马尾松林>针叶混交林>柏木林; 凋落物储量为10 52~21 90t·hm-2, 平均为17 61t·hm-2, 依次为针阔混交林>马尾松林>柏木林>针叶混交林>灌木林; 凋落物最大持水量为2 66~4 19mm, 平均为3 48mm, 依次为柏木林>针叶混交林>针阔混交林>马尾松林>灌木林; 土壤层非毛管蓄水量为34 68~ 44 16 mm, 平均为40 35mm,依次为柏木林>针阔混交林>针叶混交林>马尾松林>灌木林; 各种森林生态系统能够截留的降雨量总量为377 6~494 6t·hm-2, 平均为446 56t·hm-2, 柏木林的涵养水源功能最好, 针阔混交林、针叶混交林、马尾松林次之, 灌木林最小

A comparative study on water conservation capacity of five main forest types

Based on the data from fixed sample plots of main forest types in Lianxiahe small watershed of Three Gorge Reservoir (Area) of Changjiang River,water conservation capacity had been studied.The results showed that there is a binary linear regression for both throughfall and stemflow to precipitation quantity and precipitation intensity, and a power regression for canopy interception to rainfall.The relative interception ranges from 16.34% to 27.43% on an average of 22.15%. Under the same rainfall,the decrease order of canopy interception in the different forest types is coniferous and broad-leaved mixed forest,masson pine forest,coniferous forest and cypress forest. The biomass of litter layer in different forest ecosystems varies from 10.52 to 21.90 t·hm~(-2) on an average of 17.61 t·hm~(-2),and the decrease order of the biomass is coniferous and broad-leaved mixed forest,masson pine forest,cypress forest,coniferous forest and shrubbery .The maximum water holding capacity of litter formed in the different forest ecosystems varies from 2.66 to 4.19 mm on an average of 3.48 mm, and the decrease order is cypress forest,coniferous forest,coniferous and broad-leaved mixed forest,masson pine forest and shrubbery. The water holding capacity of non-capillary porosity of soil layer in different forest ecosystems varies from 34.68 to 44.16 mm on an average of 40.35 mm,and the decrease order is cypress forest, coniferous and broad-leaved mixed forest,coniferous forest, masson pine forest and shrubbery. The total interception of rainfall in different forest ecosystems varies from 377.6 to 494.6 t·hm~(-2) on an average of 446.56 t·hm~(-2), the decrease order is cypress forest,coniferous and broad-leaved mixed forest, coniferous forest, masson pine forest and shrubbery.