海拔对纳帕海季节性湿地植被分布格局影响初探∗

摘要

利用物种海拔分布范围(Rs)作为定量研究物种对环境适应能力的一个基础指标，以纳帕海季节性湿地这样一个近似平面的生态系统做为研究对象，结合GIS技术和野外实地调查，对物种分布格局、物种对水因子的适应性、水因子分布梯度和优势物种分布面积进行统计和可视化分析。研究结果表明：研究区域内优势物种的分布受水因子分布梯度的显著影响，在物种处于同一主导因子作用的情况下，处于同一竞争水平物种的分布面积与Rs没有明显相关性，但与基于Rs的Msh值(物种海拔分布范围中间值与当地海拔的差值)则表现出明显的负相关关系。结论说明Msh可作为定量研究物种对环境适应能力的一个指示指标，该指示指标可能对解释生态系统内物种分布格局有重要的生态意义。%This study used plant species’ distribution range along elevation (Rs) as the basic indicator to quantitatively study the plant’s environmental adaptation capacity within Lake Napahai seasonal wetland ecosystem. Throughout field survey and GIS tech-nology, this paper synthetically analyzed the plant distribution pattern, the species’ adaption to water factor and gradient distribu-tion of water, and the dominant plant species’ distribution area. The results showed that the distribution of the dominant plant spe-cies was largely affected by the distribution gradient of water factor. Under the same leading ecological factor ( water) , the distribu-tion area of the dominant species at the same competitive level had no significant correlation with the Rs while had apparent loga-rithmic negative correlations with the absolute difference value of altitudinal distribution range minus local elevation (Msh), finding explained that Msh could be an indicating parameter for quantitative research on plant species environmental adaptation capacity, which might have significant ecological meaning on illustrating plant species distribution pattern in such an ecosystem.