长江上游亚高山暗针叶林林地水文作用初探

通过对贡嘎山林区不同类型峨眉冷杉(Abies fabri)林死地被物层和土壤层的野外调查与室内分析,初步研究了长江上游亚高山暗针叶林林地水文作用.结果表明,枯枝落叶层是保证森林充分发挥水源涵养作用的一个重要层次,具有明显的蓄水保水作用,不同类型峨眉冷杉林死地被物层有效拦蓄量的排序为过熟林>成熟林>中龄林>针阔叶混交林>灌木林,其中成过熟林的有效拦蓄量为4.8～7.4 mm,而其它群落一般则小于2 mm.不同森林植被条件下土壤涵蓄量存在着明显的差异,其涵蓄量的顺序为成熟林>中龄林>灌木;同一森林植被条件下,坡积物土壤的有效涵蓄量为冰碛物土壤的3～4倍,需要在今后森林经营和开发建设中予以足够的重视.

Hydrological effects of forest land in sub-alpine dark coniferous forests of the upper reaches of Yangtze River

The hydrological effect of forest soil layer in sub alpine dark coniferous forests of the upper reaches of the Yangtze River was researched by analyzing the soil layer and debris layer in different types of Abies fabri lands in the Gongga Mountains. The result shows that the debris layer is very critical in sustaining the forest hydrological function which is so obvious in the soil and water conservation. The order of the effective water sustaining ability of debris layer in different types of Abies fabri land is over mature forest> mature forest> half mature forest> broad needle mixed forest, in which the effective water sustaining amount of over mature forest and mature forest is 4 8～7 4 mm and the others are less than 2 mm. The water sustaining ability of soil layer in different types of forest land is very different, the order of which is mature forest> half mature forest> shrub. In the same type of forest land, the effective water sustaining water of soil in slope deposit is 3～4 times more than that of drift soil, which should be given more attention in forest management and development.