Community structure and plant diversity of a Platycladus orientalis recreational plantation in West Mountain area of Beijing

Key words: 
• forest ecology /
• Platycladus orientalis /
• recreational plantation /
• dominant population /
• spatial distribution pattern /
• total community diversity /
• growth form

Abstract: To scientifically manage Platycladus orientalis recreational plantations using principles of community ecology in West Mountainou area of Beijing，characteristics of plant composition，vertical structure，spatial distribution patterns，and plant diversity were systematically studied using componential analysis，hierarchical clustering，the variance to mean method，richness indices（R，Dgl，Dma），diversity indices （Dsi，Dsh，Dmc），evenness indices （Jsi，Jsh，Ea），and total community diversity indices. Higher vascular plants in this community revealed 32 families，59 genera，and 63 species reflecting the floral features of a temperate zone. Community stratification was distinct and quantitatively divided into three major theoretical layers：tree，shrub，and herb，with dominant populations in each layer. P. orientalis tended to a random distribution（C＜1，t＜t0.05），whereas undergrowth，such as Vitex negundo var. heterophylla，Grewia biloba，and Oplismenus undulatifolius，clumped （C＞1，t＞t0.01） with unification of various degrees. Species richness and diversity by layer were：shrub＞tree＞herb （P＜0.05） with species evenness of：tree and shrub ＞ herb （P＜0.05）. Contribution rates to general community diversity were：tree：0.696，shrub：0.204，and herb：0.100. For the development of plant species diversity，shady slope was a priority. Also，to create recreational space in plantations with biodiversity，a low density （756－933 plantshm-2），which helped maintain a higher plant species diversity，was recommended.［Ch，2 fig. 4 tab. 22 ref.］