西藏色季拉山不同海拔梯度急尖长苞冷杉林土壤水源涵养功能研究  

Water Source Conservation Function of Abies georgei var. smithii Forest at Different Elevations of Sygara Mountains

作　　者：石玉龙[1] 周晨霓[1] 邱英强 王建锋[1] 

机构地区：[1]西藏大学农牧学院高原生态研究所,西藏林芝860000

出　　处：《西部林业科学》2016年第4期147-153,165,共8页Journal of West China Forestry Science

基　　金：西藏自治区"基于多源遥感影像及BP神经网络模型的色季拉山区鲁朗河流域森林动态变化分析"项目;国家西藏林芝森林生态系统定位站资助项目(2012-LYPT-DW-016);西藏大学农牧学院定位站开放课题(XZA-211-0713-D)

摘　　要：对西藏色季拉山急尖长苞冷杉林3 700~4 200m海拔梯度上土壤物理性质、持水性能及土壤渗透性能进行测定,研究其土壤水分物理性质和水源涵养功能特征。结果表明:西藏色季拉山急尖长苞冷杉林土壤容重在垂直剖面上表现为随着土层的加深而增大,随着海拔梯度的上升而减小。而土壤总孔隙度的变化特征与土壤容重正好相反,其中海拔4 200m处0~10cm土层的土壤容重最小,为0.561g/cm^3;海拔3 800m处、20~40cm土层的土壤容重最大,为1.1g/cm3。土壤最大持水量、最大滞留水量、饱和贮水量均随着海拔的上升而增加,土壤入渗性能指标(初渗速率、稳渗速率、平均渗透速率、渗透总量)在同一海拔梯度不同土壤层次上均表现为随着土层深度的加深而逐渐减小的趋势。从不同海拔梯度看,4个入渗指标在海拔3 700m处呈现最大值,而在海拔4 200m处呈现最小值。通过主成分分析综合评价,海拔4 100m处急尖长苞冷杉林土壤涵养水源功能最强,而海拔4 200m和海拔3 900m处最弱。总的来说,林线植被生境的脆弱和人为干扰是影响色季拉山急尖长苞冷杉林土壤水源涵养功能的重要因素。Soil physical properties and water source conservation function of Abies georgei var. smithii forest at dif-ferent elevations from 3 700m to 4 200m of Sygara Mountains in Xizang were comprehensively evaluated. The re-sults showed that the soil bulk density increased gradually with the increase of soil layer and it decreased with the increase of elevation, while the changing characteristics of soil total porosity was the opposite of soil bulk density. The soil bulk density at 4 200m of 0~10cm soil layer presented the minimum value with 0. 561g/cm3 . It reached the maximum value with 1. 1g/cm^3 at 3 800m of 20~40cm soil layer. Soil maximum moisture capacity, maximum water-holding capacity, and saturation water storage were all increased with the increase of elevation. Soil infiltra-tion indicators （ initial infiltration rates, steady-state infiltration rates, mean infiltration rates, and the total pene-tration） were decreased with the increase of soil depth at the same altitude. Four soil infiltration indicators showed the maximum value at 3 700m, and the minimum at 4 200m. Through PCA, the soil and water source conserva-tion function at 4 100m were the strongest, and weak at 4 200m and 3 900m. In general, the most important in-fluence factors of soil and water source conservation functions of Abies georgei var. smithii forest in Sygara Mountains were the fragile habitat of Alpine tree line and the human disturbances.

关 键 词：水源涵养 土壤特性 急尖长苞冷杉 色季拉山 海拔梯度 

分 类 号：S714.7[农业科学—林学]