ABSTRACT

This study investigated the differential response to rainfall of soil moisture infiltration in the permafrost area of the downhill slope and in the seasonally frozen ground area of the uphill slope in Kangqiong small basin on the Qinghai-Tibet Plateau. The results show that: (1) influenced by the barrier of the permafrost layer, the suprapermafrost water level in the permafrost area rises significantly, while in the seasonally frozen ground area, the soil moisture infiltration is dominated by lateral flow and downward infiltration. (2) With the thawing of soil, the soil water content in the permafrost area gradually increases to reach a saturated state. Influenced by terrain, soil texture, evapotranspiration and infiltration capacity, the variation in the topsoil moisture content is large in the seasonally frozen ground area. (3) The presence of regional talik groundwater leads to a slight increase in the water level on the uphill slope. In addition to rainfall infiltration, the change in water level on the downhill slope is also affected by talik groundwater, which causes the rapid rise of water level on the down slope.

摘要

本文研究了青藏高原康琼小盆地下坡多年冻土区和上坡季节性冻土区土壤水分入渗对降雨的差异响应。结果表明：（1）在多年冻土层的屏障作用下，多年冻土区的超霜冻水位明显升高，而在季节性冻土区，土壤水分的渗透以侧向流和向下渗透为主。（2）随着土壤融化，多年冻土区土壤含水量逐渐增加，达到饱和状态。受地形，土壤质地，蒸散量和入渗能力的影响，季节性冻土区表土水分含量的变化较大。（3）地区滑石粉地下水的存在导致上坡的水位略有增加。除降雨入渗外，下坡的水位变化还受滑石粉地下水的影响，这导致下坡的水位迅速上升。