Abstract: The community characteristics and dynamics of Abies chensiensis forest distributed on Shiren Mountain Nature Reserve were investigated. The results showed that the community was composed of 61 seed plants belonging to 27 families and 40 genera. The vertical structure of the community was simple which could be divided into tree layer, shrub layer and herb layer. The large and middle DBH class individuals of A. chensiensis and Pinus armandii were dominant. While seedlings and sapling classes were less which belong to declining population. The small DBH class and young trees of Sorbus hupehensis population were dominant which belong to progressing population. The results of quantitative classification showed that the community could be divided into 5 types: ①Ass. Abies chensiensis+Sorbus hupehensis-Rosa davidii-Zoysia japonica, ②Ass. Abies chensiensis +Pinus armandi-Rhododendron concinuum-Veratrum nigrum, ③Ass. Abies chensiensis+Acer griseum-Rosa xanthina-Dendranthema indicum, ④Ass. Abies chensiensis+Pinus armandi-Fargesia nitida-Arctium lappa, ⑤Ass. Abies chensiensis+Quercus acutidentata-Fargesia nitida-Oenanthe javanica. These five types are all in for the process of succession. It should be carried out the strategy for in situ conservation and reduced human interferences in the forest rehabilitation in order to accelerate the natural regeneration.

Key words: Spodoptera litura, Microplitis sp., Spodoptera litura nuclear polyhedrosis virus, Virus transmission