高原农业2025，Vol.9Issue(5)：585-595,11.DOI:10.19707/j.cnki.jpa.2025.05.006
拉月曲-帕隆藏布-雅鲁藏布江流域不同海拔土壤可蚀性K值空间差异性分析
Spatial Variability of Soil Erodibility(K Value)Across Different Elevations in the Layequ-Palung Zangbo-Yarlung Zangbo River Basin
摘要
Abstract
To investigate the distribution characteristics and driving mechanisms of soil erodibility(K factor)under different altitudinal gradients in the Layuequ-Parlung Zangbo-Yarlung Zangbo River Basin,five representative sampling sites were selected along a typical hydrological transect from Sejila Mountain to Motuo(including Lulang,Layue,and Gongricun).Based on field sampling and K factor estimation using the EPIC model,the relationships among soil physicochemical properties,particle-size composition,and K values were systematically analyzed.The results showed:(1)With increasing altitude,soil bulk density increased,while porosity,organic matter content,and aggregate stability decreased significantly;(2)K values in high and sub-high altitude regions were significantly higher than those in middle and low altitude areas,and the silt content was highly positively correlated with K values(r=0.907,P<0.01),serving as the dominant factor influencing spatial variation in soil erodibility;(3)The altitude at 2,378 m exhibited the highest K value(0.3 221 t·hm2·h/(MJ·mm·hm2)),which was significantly higher than those at 741 m(0.2 163 t·hm2·h/(MJ·mm·hm2)and 1,380 m(0.2 090 t·hm2·h/(MJ·mm·hm2)).This study reveals that the downstream-decreasing terrain-climate gradient along the river exerts a strong control on the spatial pattern of K values by regulating soil structure and particle composition.These findings provide theoretical support for soil erosion risk assessment and ecological conservation in high-altitude mountainous regions.关键词
土壤可蚀性K值/海拔梯度/土壤理化性质/拉曲—帕隆藏布—雅鲁藏布江流域Key words
Soil erodibility(K Value)/Altitude gradient/Soil physical and chemical properties/Layequ-Palung Zangbo-Yarlung Zangbo River Basin分类
农业科技引用本文复制引用
杨来仙,高鑫,曹盛明,张娟,骆师堂,万丹..拉月曲-帕隆藏布-雅鲁藏布江流域不同海拔土壤可蚀性K值空间差异性分析[J].高原农业,2025,9(5):585-595,11.基金项目
藏东南土壤有机碳高异质性成因与高精度量化研究项目(41930754)资助. （41930754）
