亚高寒草甸植物群落物种-面积曲线的研究

he species-area relationship (SAR) characterizes the variation in the observed number of species with increased sample area. It played a important role in understanding the generation and maintenance of biodiversity. SARs are used for estimating species richness at different scales and for estimating species extinction probability due to habitat loss. The shapes of the species-area relationships vary according to sampling methods, spatial scales and regional differences. In this paper, I studied three plant communities in different habitats (north-facing slop, souting-facing slop and flat field) of subalpine meadow, and three commonly used species-area models (exponential curve, Power curve, logistic curve) were fitted to the data respectively. I found that the logistic model satisfactorily describes the species-area data for all the samples, and I concluded that the logistic model will work best if the species are randomly distributed in space.