玛纳斯河谷水源地植被生态水位区间研究

Depth Interval Study of Vegetation Ecological Groundwater in the Water Source Area at Manaz River Valley

干旱半干旱地区地下水对植被生长起着至关重要的作用,科学定量植被生长和地下水位埋深的依存关系对干旱区生态维护与修复意义重大。结合野外植被样方调查,采用高斯模型对玛纳斯河谷水源地区域植被特征与地下水埋深间的关系进行了分析,对研究植被生态水位区间的确定进行了探讨。研究结果表明,玛纳斯河谷水源地植被沿河谷洼地向东西两侧阶地呈显著的垂直地带性分布;各种植被多度与地下水埋深间的关系符合高斯分布,灌、草群落对地下水位埋深的响应有显著区别;地下水埋深在1~4 m最适宜灌木植被生长,其限制水位为5.5 m;地下水位埋深在0.5~1.5 m时最适宜草本植物生长,其限制水位为2.5 m。研究区总体的植被生态适宜水位区间为1.0~5.5 m,生态警戒水位为5.5 m,生态水位下限为9 m。

Underground water lever plays an important role for the vegetation growth at arid and semi-arid region, and it has great significance for arid ecological maintenance and repairing through scientifically determining the relationship between vegetation growth factors and the corresponding groundwater level. Based on the field vegetation investigation,Gauss model is used to build the relationship between vegetation characteristics and groundwater depth at the Manaz River valley source area, and the groundwater depth intervals of vegetation are discussed. The results indicate that the vegetation shows a significant vertical zonality towards the east and west sides of the terrace along the valley depression. The relationships between groundwater depth and abundance of all vegetation types are in accordance with Gaussian distribution, and there are some significant differences for shrubs and herbs to groundwater level. Based on the simulation results, shrub plant abundance may achieve the max value when the groundwater depth is 2.6 ms, the most suitable water depth interval is 1-4 m, and the limit water level of shrub plant is 5.5 m. And for the herbaceous plant, abundance may achieve the max value when the ground water depth is 1.0 m, the most suitable water depth interval is 0.5-1.5 m, and the limit water level is 2.5 m. The overall ecological groundwater depth interval of vegetation is 1.0-5.5 m, the ecological warning level is 5.5 m,and the minimum ecological limit of water level is 9.0 m for the source area of Manaz River valley.