%A Chen Huijun, Du Hu, Song Tongqing, Peng Wanxia, Zhang Hao, Su Liang, Zeng Fuping %T Numerical classification of associations and their stabilities of karst evergreen deciduous broad-leaved mixed forests in Mulun National Nature Reserve %0 Journal Article %D 2019 %J Biodiv Sci %R 10.17520/biods.2019215 %P 1056-1068 %V 27 %N 10 %U {https://www.biodiversity-science.net/CN/abstract/article_60342.shtml} %8 2019-10-20 %X

Understanding plant composition, community structure and community distribution of karst climax communities can provide a reference for biodiversity conservation and forest management. Based on topographic factors, soil factors and species composition data of a 25 ha forest dynamic plot in Mulun, Guangxi, we numerically classified the association of karst evergreen deciduous broad-leaved mixed forests multivariate regression trees and a modified Godron stability analysis ( Godron, 1971; Zheng, 2000) method to measure the stabilities of associations. The results showed that the forest community was divided into six associations. They were as follows: (I) Ass. Cryptocarya microcarpa + Itoa orientalis + Lindera communis, (II) Ass. Cryptocarya microcarpa + Cleidion bracteosum + Brassaiopsis glomerulata, (III) Ass. Platycarya longipes + Rapanea neriifolia + Clausena dunniana, (IV) Ass. Platycarya longipes + Luculia intermedia + Clausena dunniana, (V) Ass. Cryptocarya microcarpa + Brassaiopsis glomerulata + Eurycorymbus cavaleriei, (VI) Ass. Boniodendron minus + Rubovietnamia aristate + Platycarya Longipes. Except for Ass. I, diversity indices of each association were higher. Shannon-Wiener index, Simpson index and Pielou evenness index showed similar trends: Ass. VI > Ass. V > Ass. IV > Ass. III > Ass. II > Ass. I. Species richness did not follow this trend and decreased in the following order: Ass. VI > Ass. IV > Ass. V > Ass. I > Ass. III > Ass. II. Species diversities of these associations were highest at middle altitudes. The stabilities of associations were highest at medium-high slope positions, while associations were lowest in depressions. Elevation is critical for community structure and composition and may be an important factor affecting community distribution.