Diversity and Flora of Seed Plants of Wetland in Sichuan Province

Based on the second wetland resources investigation in Sichuan from 2011 to 2012, analysis was made on flora of seed plants in wetlandsof Sichuan province. The results showed that there were 948 species, belonging to 334 genera and 80 families, including gymnosperms (2 species of 2genera and 1 family) and angiosperms (946 species, 332 genera and 79 families). Among them, 6 species are listed in national key protection and 5ones are rare and endangered. The dominance of plurimotypic families and genera of wetland seed plants was obvious, and the flora was ancient withrare endemic genus. At family level, there were 8 types and 6 sub-types, dominated by Cosmopolitan and Pantropic, indicating strong tropicalproperty, and at genus level, there were 14 types and 8 sub-types dominated by Temperate, especially North temperate elements, showing tropicaltemperate characteristics. It had slightly more Temperate elements than tropic ones, and Sino-Himalaya components were dominant, illustrating thatdistribution of wetland seed plants in Sichuan province had been strongly influenced by subtropical mountain climate led by Tibet plateau uplift, andreflecting a transition from tropical to temperate. Meanwhile, Sino-Japan components occupied large ratio, which indicated that it had chose relationwith flora of Japan. Differentiation intensity of family was 4.2, that of genus was 2.8 and of species was 0.07. Similarity analysis demonstrated thatseed plant flora of wetland in Sichuan，Yunnan, Tibet and Hubei shared the same origin and the background of species differentiation.