陕北黄土区陡坡柠条林地雨水转化及土壤水分承载力

Rain Transformation and Soil Water Carrying Capacity of Caragana Microphylla Forest in Steep Slope on Loess Region in Northern Shaanxi Province

为了给陕北黄土区陡坡灌木林地的可持续健康发展提供科学依据,连续3 a对陡坡柠条林地的降雨、冠层截留、地表径流、降水入渗深度和土壤水分进行了定位观测。结果表明:陡坡柠条林地林冠截留总量平均占总降雨量的11.73%;地表径流量占降雨量的16.275%;自然降雨入渗深度为120 cm;陡坡柠条林地降雨量(P)与根层土壤水分补给量(SWS)、根层平均土壤水分补给量(Y补)与密度(D)、土壤水分消耗量与密度均呈线性关系。陡坡地土壤水分可承载的柠条密度为2 852穴/hm2。因此建议陡坡柠条林地建设中适当控制密度,合理利用雨水资源,确保陡坡柠条林地的持续健康发展。

In order to provide the scientific basis to sustainable healthy development of shrub land in steep slope on loess region in northern Shaanxi,rain,interception,runoff,natural precipitation infiltration depth and soil water dynamics in peashrub forest on sloping land in loess region of Northern Shaanxi had observed at fixed position from 2006 to 2008 continuously.The results indicated： interception of shrub land in steep slope accounts for 11.73% of the total rainfall;runoff accounts for 16.275% of mean precipitation;natural precipitation infiltration depth is 120 cm;relationship between natural precipitation and soil water supply,between soil water supply and density,between soil water consumption and density are all tested linear relationship.In this region the peashrub density carrying was 2 852 clump/hm2 on sloping land.We propose to control density suitable,uses the rain water resources reasonably,achieve sustainable and healthy development of peashrub forest land on steep slope.