关键词: 单倍体, 单倍体

Abstract:

To research the Davidia involucrate community situation in Badagongshan Nature Reserve, Hunan Province, using the sample plot method to analyze the floristic composition, structure, physiognomy and species diversity of Davidia involucrate community in Badagongshan Nature Reserve, Hunan Province, by field investigation of a 4000 m2 plot. The results showed that there were 160 vascular plant species in the community belonging to 73 families and 132 genera. The largest composition of Davidia involucrata community was the North Temperate Zone Plants, reached to 25.87 % (37 genera). Then was east Asia, about 16.08% (23 genera). The community vertical structure was simple, which composed of tree layer, shrub layer, herb layer and interlayer plant. Herb layer was better than tree layer and shrub layer. In term of life form, 42.8% was phanerophytes and was similar to that in subtropical evergreen and deciduous forest. The Richness index, Simpson dominance index, Shannon-Wiener index had similar trend, with herb layer>shrub layer>tree layer in the community. But Pielou evenness index was herb layer >tree layer >shrub layer. The species component of Davidia involucrate community had the typical transition characteristics that from the subtropics to the temperate zone. The community growth situation between metaphase normal growth and decline stage, and had not yet developed into its climax.