Modeling Study On Species Richness For Seed Plants In China’s Nature Reserves

The spatial distribution of species richness is an important issue of the ecology research and has important significance in the background of global climate change. In this study, the species richness of seed plants from 155 nature reserves in China are used as basic data. We established biodiversity models for whole seed plants and trees, shrubs, woody and herbs classified based on life form in the arid area, the moist-cold area, the moist-warm area and the moist-hot area of China through the stepwise regression analyses. We also obtain the dominant factors and analyze the effects on species richness models. The main results are listed as following:(1) The R2 of whole seed plants, trees, shrubs, woody and herbs models are 0.898, 0.872,0.597,0.554,0.646 in the arid area of China; The R2 of the moist-cold models are 0.843,0.556,0.640,0.624,0.842; The R2 of the moist-warm models are 0.585, 0.810,0.732,0.761,0.580; The R2 of the moist-hot models are 0.474,0.505,0.396, 0.379,0.531. The explanatory power of the moist-hot models is lower than other models in other areas.(2) The explanatory power of dominant factors in the arid area of China is 69.4%, 46.2%,59.7%,55.4%,64.6%. In the moist-cold area, the explanatory power is 43.8%, 55.6%,40.4%,38.3%,52.2%. In the moist-warm area, the explanatory power is 38.3%,32.8%,33.0%,34.5%,18.3%. In the moist-hot area, the explanatory power is 32.1%,14.1%,26.4%,22.2%,41.0%. The explanatory power of the dominant factors in the moist-hot area is lower than other areas.(3)A11 species richness in the arid area of China have a strong correlation with water factors, and partial correlation coefficient reached 0.740 or more. All species richness in the moist-cold areahave a strong correlation with energy factors, and partial correlation coefficient reached 0.620 or more. The partial correlation coefficient with habitat heterogeneity factor is higher than the water and energy factor for each species richness in the moist-warm area and the moist-hot area. Regional scarcity factor decide the regional species richness and habitat heterogeneity factors dominate the explaination of species richness in the area with sufficient hydrothermal conditions.In this study, we established species richness models for seed plants in the arid area, the moist-cold area, the moist-warm area and the moist-hot area of China and explored the potential law between species richness and hydrothermal factors in China. This study provided a reliable basis to understand the formation and evolution of Chinese vegetation species richness patterns, and provided a theoretical basis for the development of vegetation biodiversity conservation and restoration in the future.