祁连山寺大隆林区土壤水分动态研究

Soil Water Dynamics in Sidalong Forest Region of Qilian Mountains

通过对祁连山寺大隆林区云杉林、圆柏林、灌丛林、放牧草地等４种主要植被类型土壤水分动态的长期定位研究，揭示出生长季节内各植被类型的土壤水分动态变化规律：土壤水分的年变幅以云杉林为最小，各类型土壤含水量随土层深度增加而递减，均分为３个作用层。土壤０ｃｍ～８０ｃｍ年平均持水量、多年平均持水量以灌丛林最高，分别为２２８ｍｍ、３９１．９２ｍｍ，云杉林、圆柏林、放牧草地依次递减。雨季土壤水分的消退以表层最快，向下呈递减趋势，而且因土壤类型不同差异较大；评价土壤水分有效性认为云杉林土壤水分供应状况最好。雨季是本区最佳的造林季节。

By long located experiment on soil water dynamics of the four main forest types, i. e., Picea asperata, Sabina chinensis, shrues, grazing land, soil water dynamics was revealed: the soil water dynamics of bryophyta-spruce forest was the least. The water holding capacity of different forest types decreased with the depth of soil. The annual average water holding capacity of shrub was the best (228mm and 391.92mm). The loss of water content in surface soil was the fastest and decreased with depth of soil. It is thounght the soil water content of bryophyta- spruce forest. The best afforestation season is the rainfall period in the region.