荒漠—绿洲边缘区土壤水分时空动态研究

Study on Spatial and Temporal Dynamic of Soil Water Content in Desert-Oasis Ecotone

有梭梭群落和骆驼刺群落覆盖的沙地土壤剖面的含水量与裸沙地含水量显著不同,与前者相比,裸沙地土壤水分无明显的层次性变化,受降水及蒸发等因子影响明显。不同植物群落沙地土壤水分呈现明显的土壤水分积累期(4～5月、9月)、土壤水分消耗期(6～8月)和土壤水分稳定期(10月至次年3月)的季节性特点。不同坡位土壤水分基本呈现出从小到大的顺序是坡顶<中坡<丘间地。由于植被覆盖状况和土壤物理性质不同,土壤水分随坡度的变化幅度也有明显差异,与坡顶、中坡相比,丘间地土壤水分含量较高,最高达到14.60%。

Based on the results of the long term and position research, the soil water content in the sandy soil profiles that covered the Haloxylon ammodendron Bge community and the Alhagi sparsifolia community differ from the soil water content in bare sand profiles. Compared with the former, the soil water content has no obvious horizon variety in bare sand profiles but it is greatly influenced by the precipitation and evaporation. The dynamic of soil water content in the different sandy profiles has obvious seasonal characteristics for the different plant community distribution. It can be divided into three periods, i.e. soil water accumulation (April to May, September), soil water consumption (June to August) and soil water stability (October to the next March). The variable range of soil water content distribution in the slope is obviously because the situation of vegetation cover and soil physical features are different. Compared with the top of slope and middle slope, the bottom of slope has higher soil water content, the maximum is 14.60%.