青藏高原温泉地区土壤黏粒含量剖面分布模式及其影响因素

以青藏高原温泉地区作为研究区域,通过野外土壤调查,获取了58个深度大于1m的土壤剖面,分析了变异系数最大的黏粒剖面分布模式及其与气候、地形、植被和成土母质等环境变量之间的关系。结果表明:青藏高原温泉地区土壤砂粒含量最大,占80%以上,但黏粒的变异系数最大;温泉地区黏粒含量的剖面分布模式可分为递减型、先增后减型、先减后增型和不规则型4类;递减型分布模式的主控因子是坡度、坡向和冷季地温,先增后减型分布模式的主控因子是暖季和冷季地温,先减后增型分布模式的主控因子是高程、地形湿度指数和NDVI,不规则型分布模式的主控因子是地形湿度指数、平面曲率和高程。研究表明,青藏高原温泉地区气候和地形因素是影响土壤黏粒剖面分布模式的决定性因素。

Profile Distribution of Soil Clay Contents and Its Influencing Factors in the Wenquan Regions of the Qinghai-Tibetan Plateau

The vertical distribution pattern of soil particle composition is the basis for the study of soil-landscape and soil texture three-dimensional mapping, which is of great significance for understanding regional soil information. The Qinghai-Tibet Plateau (QTP) is the permafrost region with the highest altitude and the largest area in the middle and low latitudes, which will have an important impact on global climate change,however, there are few literatures on the profile distribution pattern of soil texture composition and its influencing factors on the QTP. In this paper, the Wenquan area was used as the research area of the QTP, 58 soil profiles with depths greater than 1 m were surveyed in the field, and the profile distribution patterns of clay contents with the largest coefficient of variation and its relationship with environmental variables such as climate, topography,vegetation and soil parent material were analyzed. The results showed that the sand content of the Wenquan area is the largest, more than 800g/kg, but the coefficient of variation of clay content is the largest. The profile distribution patterns of clay contents can be divided into four types, i.e., decreasing , increasing first then decreasing, decreasing first then increasing and irregular. The main controlling factors were slope, aspect and the cold season ground temperature for the decreasing pattern, the surface temperature for the increasing first then decreasing pattern, elevation, topographical humidity index and NDVI for the decreasing first then increasing pattern, and topographical humidity index, plane curvature and elevation for the irregular pattern. The above results indicate that the climate and topographic factors are the decisive factors affecting the profile distribution pattern of clay content in the Wenquan area of the QTP, which could provide a scientific basis for studying the soil-landscape model and spatial distribution of soil texture in the QTP.