Structural characteristics and species diversity for survival of the rare plant Ostrya multinervis

Ostrya multinervis is an endangered species to China. To understand the O. multinervis plant community's structural characteristics and species diversity so as to protect this rare and endangered plant. A survey of the community structure and species diversity of O. multinervis was conducted through quadrat sampling at Shiyang Forest Farm, Wencheng County, Zhejiang Province. Using permanent plots and the technique of examining every individual, all trees in quadrats established in the community to quantify the community structural characteristics were identified and measured. Analysis included the Shannon-Wiener, Simpson, and Pielou indexes. Results showed 40 families, 52 genera, and 60 species of vascular plants with eight species of pteridophyte belonging to seven genera in six families, one species of gymnosperms belonging to one genus in one family, and 51 species of angiosperms belonging to 44 genera in 33 families. The vertical structure was composed of three layers:tree layer, shrub layer, and herb layer, in which O. multinervis was the dominant species in the tree layer, Illicium lanceolatum was the dominant species in the shrub layer, and Diplopterygium glaucum was the dominant species in the herb layer. Overall, phanerophytes accounted for the greatest number (41.7%). Species richness for the shrub layer was the largest of the three communities with the Shannon-Wiener, Simpson, and Pielou indexes larger than herb and tree layers(P < 0.05). Tree height distribution in the tree layer for whole trees was relatively uniform, the diameter order was an inverse J type species distribution, and tree height and diameter structure showed near normal distributions for O. multinervis. In summary, O. multinervis communities had a high species diversity and community stability, but were endangered by a lack of young individuals which could be overcome with closure of hillsides to facilitate afforestation, strengthening of research on highly efficient breeding technologies for O. multinervis, and implementation of artificial rearing measures to ensure a normal development of the population.