Structural Characteristics of Plant Communities and Species Diversity of Natural Secondary Forests in Beigou Forest Farm

In order to understand forest community structure,species diversity and their changing dynamics and therefore to provide a reliable basis for effective biodiversity conservation,the natural secondary forest in Beigou forest farm,Weichang County,Hebei Province was selected to investigate forest communities structure and species diversity including Raunkiaer life-form,diversity index,etc.The results showed that the study area had vegetation resources of 117 species belonging to 58 families and 99 genera.Phanerophytes dominated in the communities,followed by geophyte,while other kinds of plant showed no obvious advantages.The internal lamellar structure of the community was complex,as dominated by phanerophytes lamellar and in high bud lamellar.The richness index for each plant communities could be ranked in a descending order as herb layershrub layertree layer.The diversity index differed among different layers.The evenness index varied significantly between the layers of species,in the descending order as herb layeshrub layertree layer.