A Preliminary Study on the Characteristics of Angiosperm Flora in Sichuan Region

There are 188 families, 1493 genera, 8711 species and 1252 varieties in Angiosperm flora of Sichuan region, including more than 50% of families in the world, and contacting with its adjacent area flora and the global flora widely and intimately. The richness of relict and endemic compositions shows that the Angiosperm flora in Sichuan is old and primitive. The monotypic or oligotypic families and genera are much abundant in the region meanwhile the families and genera containing more than 100 species are very luxuriant in its flora also. Although the genera with less than 5 species are about 73.80% the genera with 6-99 species, which is about 22.64% of the total genera in the flora are the main composition. The areal-types of families are mainly tropical, but those of genera and species reflect a typically subtropical characteristics. The Angiosperm flora in Sichuan region is characterized by not only obvious dominance pheneomena but also abundant endemic and characteric taxa. It is a representativeness to the ones of China and East- Asia.