青藏高原青南地区植物群落生态梯度分析

The gradient analysis of plant communities at southern Qinghai of Qinhai-Tibet Plateau

依据对青藏高原青南地区26个群落的样地调查和环境因子原始数据,用主分量分析(PCA)排序技术和回归模型,定量分析植物群落在空间的分布格局,以及群落结构特征和环境梯度之间的关系.结果表明:植物群落的类型分布主要决定于地理位置驱动下的水热条件,其次还受制于土壤养分.代表植物群落结构特征的生物多样性和丰富度分别与环境梯度有显著的相关性,随年均温和年降水量减少,群落物种多样性和丰富度有降低的趋势.

Twenty-six plant communities were surveyed by quadrats in southern Qinghai of Qinghai-Tibet plateau. The communities were analyzed using the principal component analysis(PCA) ordination and the regression procedure to determine the distribution patterns of the plant communities and the relationship between the communities and environmental factors. The results showed that the distribution of the plant communities was closely related to the annual average temperature and the annual precipitation, and also to soil nutrients. The correlation between species diversity of the communities and the gradient of environmental factors was significant, and community richness, species diversity decreased with a drop in annual average temperature and annual precipitation.