林地地上部分的持水性能及其对林地水文学性质的影响

通过对新安江水库库岸区不同林地乔木叶、灌木叶、草本和地被物生物量和持水率的测定,计算出林地地上部各层次的持水量和总持水量,并根据研究区的降水和迳流小区水土流失的测定结果,评价了不同林地的水文学特性。结果表明,影响林地持水量的主要因素是叶、地被物生物量,持水率的影响较小。生物量大,持水量则大。林木,特别是阔叶林,由于地上部分的持水作用大,显著地减小了地表适流量和土壤流失量,并能改善林区小气候。无林地的持水量很小,水土流失严重。

Water Capacity of Aerial Part Biomass and Its Effects on Hydrological Characters in the Forest Land

Through analysis to both biomass and water-holding ratio of arbor, shrub, grass and litter in the different kinds of forest land of the bank range of Xin'anjiang reseroir, the water capacity of each layer and its sum were caculated. The hydrological characters of the forest land were evaluated with reference to information of the rainfall and soil erosion in the studied site. The results showed that the main factor effecting water capacity was the biomass of leaves and litter. The more biomass, the higher water-holding content. Tree, especially broad-leaved tree, could improve microclimate, decrease significantly both amount of runoff and soil erosion. Soil erosion was serious in no-foiest land because water-holding content was lower in there.