| Biodiversity is one of the front areas of current biological research. The mechanisms of the formation, spatial distribution pattern, conservation and utilization of biodiversity have been an important area of biological and environmental research. In this study, through analyses of data about plant diversity, animal diversity, geographic factors, climatic factors, and energy factors by use of GIS software( MAPGIS and MAPINFO), statistic software(SPSS and DPS) and ecology software(CANOCO), the mainland of China was divided into 241 small districts of 2° by 2° . The environmental factors in each district were analyzed and isopleth maps of environmental elements were depicted. The isopleth maps of the number of families, genera and species of flowering plants, number of species of conifers, and number of species of ferns as well as those of mammals, birds, reptilians and amphibians were drawn. The current pattern of distribution of the flora and animal diversity in China and their relationship with environmental elements were analyzed. The major conclusions of this study are as follows.In this study, we adopted the concepts and used the state-of-the-art tools in this field to investigate the current situation and emphasized the importance and emergent necessity of protection of biodiversity in our country. China is geographically large and has variegated ecosystems, and this has made it one of the countries with the richest biodiversity in the world. More than 30000 species of seed plants, 581 species of mammals, 1244 species of birds, 376 species of reptilians, and 284 species amphibians have been identified. The biodiversity in our country is not only rich but also unique. Moreover the origin of the flora and fauna in China is old. However, because of the huge population and environmental pollution, and uncontrolled deforestation and hunting, the biodiversity in China has been decreasing quickly. About 4500 species of higher plants, 134 species of mammals, 187 species of birds, 17 species of reptilians and 7 species of amphibians are highly endangered or endangered, which is over the world average level. This has made it urgent to conserve the biodiversity.The relationships between the spatial distribution pattern of plant diversity and environmental elements were studied with such software as CANOCO, SPSS and DPS. Through classification and clustering analyses by using Cluster, we divided the mainland China into 7 large-regions representing different plant richness areas from very high to very low. The first axis of DCAordination reflects a synthetic environmental gradient, positively correlated with precipitation, humidity, heating, primary productivity, and potential evaporation etc. The second axis of DCA represents changes in altitude and longitude. The diversity of plants has a trend of increase along the first axis. The abundance of flowering plants and ferns is increased exponentially along it, and that of conifers change a little under low heat and water conditions, while the abundance of conifers increased exponentially along the axis under high heat and water conditions. DCCA and CCA showed the similar results as that of DCA. Meanwhile, we proved that the major factor that determines the distribution of plants in China is the primary productivity. The cold index (the lowest temperature) plays a more important role than the highest temperature and the annual mean temperature in restricting the diversity of plants. Within a large geographic scale, the diversity of plants is mainly influenced by latitude, while that of Qinghai-Tibetan Plateau has its unique pattern of distribution. Grey correlation analyses show that at the time axis, the factors influencing the diversity of plants strongly are primary productivity, annual precipitation, relative humidity, mean temperature in January, and potential evaporation etc.The spatial distribution pattern of terrestrial vertebrates including mammals, birds, reptilians and amphibians were studied with methods similar to those for plants. 7 d...
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