祁连山水源涵养林受立地水热条件的影响和自然、历史干扰,多世代演替共存,分布占祁连山3个垂直气候带,主要由湿性灌丛林、青海云杉林、祁连圆柏林、干性灌丛林4种类型组成,6个林型即湿性灌丛林、藓类青海云杉林、灌木青海云杉林、草类青海云杉林、祁连圆柏林、干性灌丛林。调查研究表明,各类森林枯落物(层)的现存量,组成成分、持水率、持水量等均不相同。森林土壤矿质层的主要物理性质因森林类型而不同,并均随着土壤的深度呈某种规律性的变异。森林土壤的持水量主要受土壤孔隙度的影响。在祁连山林区,森林土壤的持水量较非林地(牧坡草地)土壤为高,在各森林类型中青海云杉林和灌丛林的持水量,较祁连圆柏林为高。
Mult i- generation succession was coexisted in water conservation forest of Qilian mountain because of influences of water and hot in forest site and disturbances of nature and history. The distribution of water conservation forest accounted for three vertical climate belts in Qilian mountain and mainly consisted 4 types of wet shrub forest, Picea crassifolia forest, Juniperus przewalskii forest and dry shrub forest, 6 forest stands of wet shrub forest, moss-Picea forest, shrub-P, crassifolia forest, grass-P crassifolia forest, Juniperus przewalskii forest and dry shrub forest. The investigation results indicated that the p,fesent quantity and component of litter-fall, water holding rate and holding content of soil were all different in various types of forest. The main physical property in mineral layer in forest soil was different in various forest stands and showed some regular variation with the depth of soil. The water holding content of forest soil was mainly influenced by soil porosity. The water holding content of forest soil was higher than that of non-forest soil, and the water content of both Picea crassifolia forest and shrub forest was higher than that of Juniperus przewalskii: forest among all types of forest stands in Qilian mountainous area