Ecological Study of Forests Dominated by Endangered Species, Taxus Chinensis Var. Mairei, in Shanxi of China

Taxus chinensis var. mairei is an endemic, endangered and first-class protected tree species with great medicinal values in China. Its forest distributes in very limited region and its area is reducing during the last 30 years. Conservation of this species and its communities is urgent. This study aimed to reveal relationships of T. chinensis var. mairei forests with soil variables and topographic variables in Shanxi of China. Floristic data and environmental data from 95 samples of 10 m × 10 m in temperate region were analyzed by TWINSPAN, DCA and CCA, and species diversity indices. Eight forest associations were recognized by TWINSPAN and testified by DCA. These associations with special characteristics were main forest types of T. chinensis var. mairei. The results of CCA showed that the vegetation patterns are related to both soil variables and topographic variables. Among the soil variables, soil organic matter, water content, N, P, Zn and Mn were the most important factors explaining the spatial patterns of forest communities. The topographic variables, elevation, slope and aspect were also significantly correlated with the vegetation. Interactions between the environmental variables were apparent. Species richness, diversity and evenness were significantly related to elevation, but not significantly related to other variables. Further measures for the conservation of T. chinensis var. mairei and its forests must be undertaken.