西藏羊卓雍湖盆区土壤分布规律研究

A STUDY ON THE DISTRIBUTION PATTERN OF THE SOILS IN THE YANGZHUOYONG LAKE BASIN REGION IN TIBET

溯雅鲁藏布江而上的印度洋暖湿气流,是引起西藏羊卓雍湖盆区土壤产生水平——垂直分异的动力。本区垂直带谱可归纳为东、北部偏干型和西、南部偏湿型两类。前者带谱简单,带幅宽,基带土壤和建谱土壤多为草原土系列,山脊线是土类分界线;后者带谱复杂,基带土壤和建谱土壤均为草甸土系列,并提出了“圆锥式”和“芽状”土壤分布为湖盆区所特有的土壤隐域分布规律。

The Indian Ocean warm-moist air current moving upwards along the Yar Lu Zangbo River wasfound to be the motive force leading to the horizontal—vertical differentiation of the soils in theYangzhuoyong Lake Basin region.The 7 soil altitudinal belts of 4 mountain tops investigated in thisstudy was divided into 2 types,viz,the partial arid soil type in the north and east and the partial wetsoil type in the south and west.The former type is characterized by simple,widely—spaced altitudinalbelts and composed mainly of steppe soil series with the demarcation line of the mountain ranges as theborder lines of various soil series.The latter type is characterized by complex altitudinal belts with themeadow soils as their fundamental series.Cone—shaped or bud—like distribution regularity is consid-ered to be characteristic of the soil concealed region in the lake basin region.