Comparison Of Hydrological Ecology Between Secondary Forest And Artificial Forest Small Watershed In The Upper Reaches Of Ashihe River

Rekationship of interaction between forest and water is the key topic of forest hydrology. On the basis of studying the secondary forest and artificial forest small watershed in the upper reaches of Ashihe river, the hydrological process of diffrernt interfaced (canopy layer, litter layer and soil layer) for vegetations and characteristics for water conservation have been analyzed.Conclusions are as follows:(1) The throughfall of secondary forest and artificial forest small watershed all increased as the rainfall rose. The throughfall ratio of mature forest in secondary forest small watershed was more than nearly mature forest. The stemflow of artificial forest small watershed increased as the rainfall rose. The rainfall interception of secondary forest small watershed was more in June than other months. The rainfall interception and ratio of Pinus koraiensis plantation were the most.(2) The water holding capacity and water retention rate of plot3 in secondary forest small watershed were the highest, and that of plot 4 were the lowest. The nature water retention rate of five plots was similar in artificial forest small watershed.(3) The vertical change of soil density of plotl and plot4 in secondary forest small watershed obviously increased with the depth. The average soil density was as follow:plotl> plot2> plot4> plot3. The average porosity was as follow:plot4>plot3>plot1>plot2. In artificial forest small watershed, the soil density of mixed forest was lower than other three forest. The infiltration capacity of plotl was the best in secondary forest small watershed. The infiltration capacity of Larix gmelinii plantation was the best in artificial forest small watershed.(4) The vertical change of soil moisture content distribution was obviously decreased with the depth in secondary forest small watershed. The vertical change of soil moisture content distribution was obviously decreased with the depth in artificial forest small watershed. The transpiration intensity of broad-leaf forests was bigger than the coniferous forests. The soil evaporation and evaporation intensity of secondary forest small watershed during growing season was in such sequence:plot1>plot3>plot4>plot2. The evaporation intensity of artificial forest small watershed was in such sequence:mixed forest> Pinus koraiensis plantation> Larix gmelinii plantation> Pinus sylvestris var.mongolica plantation.(5) During growing season, the snow depth in secondary forest small watershed was similar with the snow outside of the forest. From January to March in 2009, the density of snow in secondary forest was higher than that outside of the forest. The snow depth in artificial forest small watershed varied significantly. The snow depth of mixed forest, Larix gmelinii plantation and outside of the forest was higher than that of Pinus sylvestris var.mongolica and Pinus koraiensis plantation obviously. There were little difference on the density of snow.(6) The ecological use of water in secondary forest small watershed was lower than artificial forest small watershed. The function of water conservation of secondary forest was better, and it's suitable as a water conservation forest.