Studies on the flora of seed plants in Pangquangou Nature Reserve, Shanxi Province

In Pangquangou Nature Reserve, it was known that there were 809 species of seed plants in the region ,which belonged to 359 genera and 89 families. Among them there were about 2 families 6 genera 7 species in Gymnospermae, and 87 families 353 genera 802 species in Angiospermae. 15 families were more than 5 genera and 330 genera were not more than 5 species. These families and genera played important roles in seed plants flora. Analysis based on families, genera and species shown that the floristic elements in the region were diversity. Families： Cosmopolitan type was dominant in the families. It had 40 families. North Temperate type （24 families） was on the second place. Genera： Temperate floristic elements were significant in genera flora. 256 genera belonged to temperate type, which accounted for 82.05 % in total genera. Moreover, Species endemic to China were the largest type of species elements. North of China elements were especially predominant. Some species such as Larix principis-rupprecht, Rosa xanthina and Pinus tabulaeformis were constructive or dominant species of the region vegetation. It was different in endemic of families, genera and species. There was no family, but 7 genera and 325 species were endemic to China.