Comparative Research on Hydrological Effect of Main Forest Categories in the Middle Reach of Wenyuhe Watershed,Shanxi Province

An investigation on hydrological effect of forest litter and soil for six kinds of water conservation forests was conducted in Sandaochuan forest farm,Shanxi province,by the method of field survey and indoor experiment.The influencing factors of hydrological effect in six water conservation forests were also analyzed.Results showed:(1) The needle forest hads more litter reserves than broad-leaved forests and shrub,plantation had more litter reserves than natural forests;(2) the maximum water holding capacity of soil also decreased,it sorted as follows: Larix principis-rupprechtii plantation shrub forests natural Populus davidiana stands natural Betula paltyphylla stands natural Pinus tabulaeformis stands enclosing natural Pinus tabulaeformis stands;(3)natural Betula paltyphylla stands and Populus davidiana stands had the significant differences of soil water holding capacity among the four different soil layers,while the other stands had not.(4)The hydrological effect of forest litter and soil for six kinds of water conservation forests show that Larix principis-rupprechtii plantation had the largest water conservation capacity of forest litter and soil,shrub,natural Populus davidiana stands,natural Betula paltyphylla stands,natural Pinus tabulaeformis stands followed and enclosing natural Pinus tabulaeformis stands had the smallest;(5) The stands in different succession stage had different hydrological effect significantly,mixed forsest forestation in transitional stage will improve The hydrological effect.