Species Diversity And Flora Of Bryophytes In Northwest Hunan, China

Northwest Hunan is located at 109° 10' -110° 22.5' E in longitude and 27° 44.5' -29° 38' in latitude. Located in middle subtropical climatic belt, N-W Huan's main vegetation is middle subtropical evergreen broad-leaf forests as a result. In topography, northwest part of this region is higher than southeast part. The highest peak of this region is 1936.5m, which is Dalingshan in Longshan county, while the bottom is the outlet of Dalongxi in Luxi county, only 97.1m above sea level.Taxonomic study on bryophytes of N-W Hunan has not been conducted until the author got there. In total of 1771 packages of specimens have been collected there, based on these specimens, 387 species (subspecies and varities are included) of 155 genera in 65 families are identified, among which, 2 families, 16 genera and 175 species are firstly reported for Hunan province. The author describes all the new recorded families and genera to Hunan, and takes photos of some species. Families contained no less than 10 species are defined as predominant family, then here are 12 predominant families including 71 genera and 219 species in N-W Hunan, which formed the main body of bryophytes flora of this region. While genera contained no less than 5 species are defined as predominant genus, therefore, 22 genera with 166 species are confirmed, accounting for 14.19% of the total genera and 41.81% of the total 387 species respectively. According to comprehensive evaluation of abundance, the author compares moss flora of N-W Hunan to that of other 11 regions, and Si index shows that moss flora of N-W Hunan is abundant, which ranked the forth after Dujiangyan, Mt. Jinfo and Mt. Jiuwan, while in terms of bryophytes flora, N-W Hunan champions all other 8 regions by its highest Si index.According to 'The areal-types of Chinese genera of seed plants" by Wu Zheng-yi, 14 types of the bryo-flora in this region are recognized. East Asian elements is the most important one, which contains 153 species corresponding to 42.38% of the total, Followed by temperate elements with 91 species accounting for 25.21% of the total, and tropical elements lists third by 87 species, which accounting for 24.65% of the total. Temperate elements is almost equal to tropical elements, which is in accordance...