Study On Plant Communities Of JiuLong River National Forest Park

The Jiulong River National Forest Park in Hunan Rucheng is at the mountain area of south China, which near the middle of Nanling Mountains with the south of Luoxiao Mountains, it is at the humid monsoon climate region which is the transition region of subtropical to south subtropical. In this study, evergreen broad-leaved plant communities as the main object to study, and this paper discusses and studies the following aspects:the species composition and characteristics of flora, the quantitative and structure character of community, the physiognomy of community, species diversity and so on. The results of the study are as follows:1. In the sample lands there are 267 species of vascular plants, belonging to 82 families,165 genera. The flora characteristic shows that there are both tropical elements and temperate elements, and tropical elements are more than temperate elements.2. Meso and micro-phanerophytes predominated in life-form, hemicryptophyte at the second; interlayer plants and annuals are fewer. Distribution of life-form reflects the climate in this region is moist, moderate and full of rain. On the other hand, most of the characteristic of leaves are mesophyll, nonentire leaves, leathery leaves, and simple leave, it shows the typical characteristics of sub-tropical evergreen broad-leaved forest.3. In vegetation types, evergreen broad-leaved forest dominated by evergreen tree species, and the tree layers are made up of tree species of Fagaceae, Lauraceae, Theaceae etc.4. Evenness indices of tree layer and community evenness are not high but ecological dominance is higher, indicates that there are few species control this layer, reflects the plants have good adaptation to their habitat. The species richness and diversity index reach their maximum in the middle elevation.