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塔克拉玛干沙漠南缘属典型的干旱区内陆盆地生态环境脆弱带 ,在绿洲与沙漠相互交错分布的干旱生态系统中 ,地下水显示出重要的生态调控作用 .土壤环境 (水分、土壤含盐量 )受地下水环境状况 (地下水位、水质 )的制约 ,从而决定了植被的生长情况 .地下水埋深小于 4 m时 ,土壤含水量一般在 11.7%～ 33.9%之间变化 ,荒漠河岸林、柽柳灌丛和多数草本植物均能正常生长 .当地下水位埋深大于 4 m时 ,天然植物生长明显受到制约 .土壤含盐量与潜水位埋深成反比 ,与潜水矿化度呈线性关系 ,3m为土壤盐渍化临界水位 .另一方面 ,地下水矿化度小于 3g/ L时植物生长良好 ,高于 5～ 10 g/ L生长受到抑制 .因此荒漠植被生长的最佳水文地质环境应是地下水位埋深在 3～ 4 m;地下水矿化度小于 3g/ L
The southern margin of the Taklimakan Desert is a typical eco-environment fragile zone of the inland basin in the arid region. In the arid ecosystems where the oasis and the desert are alternately distributed, the groundwater shows an important ecological regulation. The soil environment (water and soil salinity) is affected by The groundwater environment conditions (groundwater level, water quality) constraints, which determines the growth of vegetation.When the groundwater depth is less than 4 m, the soil moisture content generally changes between 11.7% ~ 33.9%, desert riparian forest, Tamarisk shrub and Most of the herbs can grow normally.When the buried depth of the local water table is more than 4 m, the growth of natural plants is obviously restricted.The soil salt content is inversely proportional to the buried depth of the phreatic water and a linear relationship with the salinity of the phreatic water, 3m is the soil salt On the other hand, when the salinity of groundwater is less than 3g / L, the plants grow well and the growth above 5 ~ 10 g / L is inhibited, so the optimal hydrogeological environment for the growth of desert vegetation should be the depth of groundwater table In 3 ~ 4 m; groundwater salinity is less than 3g / L