研究了川西亚高山林线过渡带及邻近植被土壤物理及水分特征.结果表明:林线过渡带附近年降水量为832mm,降水量分布呈单峰曲线变化,其中6月降水量最高,达174mm.林线过渡带及邻近植被土壤含水量与大气降水量具相同的季节变化.林线区域土壤全容水量与非毛管蓄水量分别介于82.84~106.76和12.34~24.49mm,下缘冷杉林最高,上缘流石滩草甸最低.从上缘流石滩草甸→林线过渡带→下缘冷杉林,土壤稳渗速率逐渐增高(分别为0.46,2.18和4.36 mm/min),蒸发性能逐渐改善,有效水含量逐渐增高,分别为15.6%,23.5%和33.8%).三类植被在中、低吸力段(〈1.5 MPa)土壤水吸力与土壤含水量之间存在显著的函数关系,经验方程:θ=AS-B对该区域土壤水分特征曲线有良好的模拟性.
In a short distance, soil water characteristics of the soil mainly taken place in residual deposits in subalpine timberline ecotone and its upper and below boundary vegetation of scree meadow and fir forest, have been studied in Wanglang National Nature Reserve in this paper. The results indicate that annual rainfall is 832 mm· a -1 and its monthly change is sole peak curve having the peak in June which is 174 mm in the region of timberline ecotone. The water content of timberline ecotone and adjacent vegetation has the same monthly change as rainfall and reaches the peak at the beginning of July. Saturated water content and potential of water content in non-capillary pores are 82.84-106.76 mm and 12.34-24.49 mm respec tively, and highest in fir forest but lowest in scree meadow. From scree meadow to timberline ecotone then to fir forest, the steady water saturating velocity (which is 0.46 mm · min^-1, 2.18 mm·min ^-1 and 4.36 mm · min^- 1 respectively), evaporating capability and available water content (which is 15.6%, 23. 5% and 33.8% respectively) are increased. Finally, there is a high power function correlation between the soil moisture content and soil suction during the low and medium soil suction(〈1. 5 MPa) and the empirical e quation θ= AS^- B could well simulate the water characteristic curves of timberline ecotone and adjacent veg etation in Western Sichuan.