藏东南典型小流域土壤饱和导水率和土壤容重空间分布

Spatial Distribution of Soil Saturated Hydraulic Conductivity and Soil Bulk Density in a Typical Catchment in Southeast Tibet

选取藏东南地区的典型小流域,通过网格法在流域的阴坡和阳坡分别采集表层(0-10cm)和底层(20-30cm)环刀土样,研究土壤饱和导水率和土壤容重在流域内的空间分布。结果表明:不同土层相比,表层土壤的饱和导水率以及土壤容重均低于底层值;阴坡和阳坡相比,阳坡的平均土壤饱和导水率和土壤容重高于阴坡,且其变异程度更大;沿坡长方向,土壤饱和导水率从坡顶到坡底呈增大趋势而土壤容重呈减小趋势;土壤饱和导水率与土壤容重之间呈显著负相关(P<0.05)。

The spatial distribution of soil saturated hydraulic conductivity and soil bulk density in a typical catchment in southeast Tibet was investigated. Soil samples of surface layer（0--10 cm） and bottom layer（20 --30 cm） on both a shady slope and a sunny slope in the study area were collected using cutting rings by grid sampling method. Results illustrated that compared with the bottom layer, soil saturated hydraulic conductivity and soil bulk density were both lower on the surface layer. Soil saturated hydraulic conductivity and soil bulk density were both higher on the sunny slope with more variation. Meanwhile, soil saturated hydraulic conductivity showed an increasing trend from the top to the bottom of the slope while soil bulk density presented a decreasing trend to the downward of the slope. Furthermore, a significant negative correlation（P〈0.05） was revealed between soil saturated hydraulic conductivity and soil bulk density.