西宁南北山主要生态景观林土壤渗透功能的分析与评价

Analysis and evaluation on permeability function of soil of the main ecological landscape forests in North-south mountains in Xining areas

为了探讨西宁南北山主要林分类对土壤渗透功能的影响状况,从土壤物理性质、渗透率、贮水量方面对土壤渗透功能进行了全面分析。结果表明:112种林分类型对土壤容重都有不同程度的影响,其中,青杨×沙棘混交林影响最大,表层土壤容重仅为0.755 g/cm3;2表层土壤渗透速率增大,不同林分在相同土质中初渗速率和达到稳渗时间差异明显,在淡栗钙土林分中最大差异分别达5.67和7.41倍;3同一土质各林分间非毛管孔隙度差异较大,河北杨×青海云杉混交林表土层孔隙度比青杨纯林高0.72倍;4各林分间水源涵养能力差异显著,河北杨×青海云杉混交林非毛管蓄水量是柽柳纯林的3.01倍;5各林分土壤渗透功能都有不同程度的改善,但差异明显。在营造生态景观林时,选择土壤渗透功能良好林分组合,可增强生态防护力度。

In order to explore how the main stand types influence the soil permeability, the compre- hensive analysis was done from soil physical, the speed of permeability, storing water. The result showed as follows： （2）12 stand types affected the soil bulk density in different degree. The soil bulk density of topsoil is greatly influenced in the mingled forest of Populus cathayana and Hippophae rh- amnoides subsp, sinensis, and it is only 0. 755 g,/cm3 , （2） Soil permeable rate is the largest in top soil than other layers in all of the 12 stand types, and initial infiltration rate and the time to reach the steady infiltration showed discrepancy in same soil texture of different stand types. The discrep- ancy were greatest in light chestnut soil, and initial infiltration rate and time to reach the steady in- filtration were 5.67 folds and 7.41 folds respectively, （~） Non -capillary porosity present great dis- crepancy in same soil texture of different stand types, Non - capillary porosity in mingled forest of Populus hopeiensis and Picea crassifolia Kom. is 0.72 times higher than that of Populus cathayana. （4） Water conservation capacity showed great discrepancy among different stand types, the capacity of Populus hopeiensis and Picea crassifolla Kom. mingle forest is 3.01 times than that of Chinese tamarix pure stand. （5）Soil permeability were improved, but showed great discrepancy among the 12 stand types. Based on these result, the stand type and groups with high capacity of soil permeability should be chosen in ecological landscape forest construction , to enhance ecological protection ef- forts.