不同海拔缓步动物群落结构的比较

Comparison of tardigrade community structure along altitude gradient.

为研究海拔对缓步动物群落结构的影响,对地处秦岭北坡的南五台山缓步动物群落进行了初步调查研究。调查设置3个样区、45个样方,共采集缓步动物919个,个体密度平均816.89个.m-2,隶属缓步动物门2纲2目3科7属11种。其中Macrobiotus hufelandi和M.harmsworthi共占总采量的92.93%,为优势类群。采用Simpson指数、Shannon-Wiener信息指数、Pielou均匀度指数和修正的Hill指数来计算各生境缓步动物群落结构特点。研究表明,海拔对缓步动物群落结构有一定的影响。随着海拔的下降其物种的个体数量、群落优势类群的数量和优势物种数都呈下降趋势;物种多样性的变化趋势为中海拔地区>低海拔地区>高海拔地区,而群落优势度的变化趋势完全相反;不同海拔样区的群落相似性较低。

To study the effects of altitude on tardigrade community structure, an investigation was made on the Mount Wutai located at the north slope of Qinling Mountains. Three areas were selected at different altitudes, and 45 sampling plots were investigated. A total of 919 individuals of tardigrade belonging to 11 species, 7 genera, 3 families, 2 orders and 2 classes, were obtained, with an average density of 816.89 individuals·m^-2. The individuals of Macrobiotus hufelandi and M. harmsworthi occupied 92.93% of the whole collection, composing the dominant groups. Simpson index, Shannon-Wiener diversity, Pielou evenness index and improved Hill index were used to evaluate the characters of tardigrade community structure in each sampling area, and Jaccard index was used to analyze the similarity between different communities. The results indicated that altitude had certain effects on the tardigrade community structure. The density, especially the population density of the dominant species, and the number of the dominant species decreased with decreasing altitude. The variation trend of species diversity was in order of medium altitude 〉 lower altitude 〉 higher altitude, while that of the dominant degree of community was on the contrary. The communities shared very lower similarity at different altitudes.