The Typical Forest Community Structure and Diversity of the Secondary Forest in Mulinzi

Based on investigating field community and using two-way indicator species analysis (TWINSPAN), we had investigated the species composition, construction and diversity features of the Carpinus fargesiana + Cyclobalanopsis glauca - Weigela japonica community and its 10 dominant populations in Mulinzi Nature Reserve. The result showed there were 8 051 individuals of ligneous plants altogether whose diameter at breast height (DBH) ≥ 1.0 cm, belonging to 149 species, 81 genera and 39 families. The tropical plant families was more dominant and had tropical-temperature intersection trends properties. In community, species were more abundant and diverse in laigh height layer, and species richness of regeneration layer take up 59.8% of whole community. In community, the species ratio of evergreen with deciduous species numbers was 0.44 : 1, the quantity ratio of evergreen with deciduous species′ individuals was 0.39 : 1. In the regeneration layer, the species ratio of evergreen with deciduous species numbers was 0.52 : 1, the quantity ratio of evergreen with deciduous species′ individuals numbers was 0.60 : 1. Among the top 10 species in importance value, only Rhuschinensis and Betula luminifera population was declining and other populations belong to the growth form. The arborets exhibit significant positive association to adult trees in dominant populations but in Litsea cubeba and Clethra cavaleriei population are less pronounced. In general, most dominant populations had well natural regeneration, small diameter class individuals grew quickly. the deciduous species had still occupied the dominant position and it had more advantage in high height layer of community.