Floristic analysis of seed plants in the Thousand Island Lake region

The flora of seed plants in the Thousand Island Lake was analyzed in this paper. There were 666 seed plant species belonging to 401 genera and 114 families. Among them,there were about 4 families,6 genera,6 species in Gymnospermeae;11 families,66 genera,95 species in Monocotyledoneae,and 99 families,329 genera,565 species in Dicotyledoneae. At family level,the pantropic,cosmopolitan and N.temp areal types were the most abundant types,and the tropic elements were more than temperate ones(48/28). At genus level,the total number of monotypic and oligotypic genera was 393 occupying 71.51% of the total genera,suggesting a dispersive pattern of genus composition in this region. The most abundant areal type was pantropic type with 94 genera and the second was N. temp type with 56 genera,which occupied 23.44% and 13.97% of the entire types respectively. It was almost equivalent between the tropic elements and the temperate ones(180/171). It's also found that habitat fragmentation might have influenced the plant composition on the islands by comparison of the analysis of flora of the continent and islands indicating there were more particular genera on the continent than the land-bridge islands.