采用典型取样和随机取样相结合的方法，对江苏宝华山植物群落的56个样方进行调查；在此基础上，以海拔和坡度为分类节点，采用多元回归树（MRT）划分群落类型，并利用相关性分析和除趋势典范对应分析（DCCA）方法对群落类型和乔木层优势种与环境因子的关系进行分析。结果显示：宝华山植物群落可分为5个群丛，即化香树+响叶杨-高粱泡-阔叶山麦冬+紫花前胡群丛（Ass. Platycarya strobilacea+Populus adenopoda-Rubus lambertianus-Liriope muscari+Angelica decursiva）（群丛Ⅰ）、朴树+黄连木-老鸦柿+茅莓-猪殃殃+明党参群丛（Ass. Celtis sinensis+Pistacia chinensis-Diospyros rhombifolia+Rubus parvifolius-Galium aparine var. tenerum+Changium smyrnioides）（群丛Ⅱ）、麻栎+栓皮栎-白马骨-柔弱斑种草+梓木草群丛（Ass. Quercus acutissima+Quercus variabilis-Serissa serissoides-Bothriospermum zeylanicum+Lithospermum zollingeri）（群丛Ⅲ）、青冈+紫楠-油茶+红脉钓樟-贯众+沿阶草群丛（Ass. Cyclobalanopsis glauca+Phoebe sheareri-Camellia oleifera+Lindera rubronervia-Cyrtomium fortunei+Ophiopogon bodinieri）（群丛Ⅳ）以及紫楠+毛竹-野鸦椿+老鸦柿-安徽碎米荠+求米草群丛（Ass. Phoebe sheareri+Phyllostachys edulis-Euscaphis japonica+Diospyros rhombifolia-Cardamine anhuiensis+Oplismenus undulatifolius）（群丛Ⅴ）。相关性和DCCA排序结果表明：海拔、坡度、坡向和坡位等环境因子与宝华山植物群落结构和种类分布总体呈显著相关，其中海拔和坡度是重要影响因子。随海拔降低、坡度加大、坡向由阴转阳，依次分布着群丛Ⅳ、Ⅴ、Ⅲ、Ⅱ、Ⅰ，呈现明显的垂直地带性分布特征。从乔木层优势种看，青冈、紫楠和红柴枝（Meliosma oldhamii Maxim.）等种类为高海拔区域的优势种；而枫香树（Liquidambar formosana Hance）、麻栎和建始槭（Acer henryi Pax）等种类对环境条件要求较低，分布范围较大；坡度和坡向对朴树、响叶杨和化香树等种类的分布有较大影响。综合分析结果表明：MRT分类结果与DCCA排序结果相吻合，即海拔和坡度是影响宝华山植物群落结构和种类分布的重要环境因子。宝华山落叶阔叶林有可能过渡为常绿落叶阔叶混交林，逐渐演替为典型地带性植被。

56 quadrats of plant community of Baohua Mountain in Jiangsu Province were investigated by classic and random sampling methods； on the basis， taking elevation and slope as classification nodes， the community types were classified by multivariate regression tree （MRT）， and the relationships of community type and dominant species in arbor layer with environmental factors were analyzed by using methods of correlation analysis and detrended canonical correspondence analysis （DCCA）. The results show that the plant community of Baohua Mountain can be classified into 5 associations， including Ass. Platycarya strobilacea+Populus adenopoda-Rubus lambertianus-Liriope muscari+Angelica decursiva （association Ⅰ）， Ass. Celtis sinensis+Pistacia chinensis-Diospyros rhombifolia+Rubus parvifolius-Galium aparine var. tenerum+Changium smyrnioides （association Ⅱ）， Ass. Quercus acutissima+Quercus variabilis-Serissa serissoides-Bothriospermum zeylanicum+Lithospermum zollingeri （association Ⅲ）， Ass. Cyclobalanopsis glauca+Phoebe sheareri-Camellia oleifera+Lindera rubronervia-Cyrtomium fortunei+Ophiopogon bodinieri （association Ⅳ）， and Ass. Phoebe sheareri+Phyllostachys edulis-Euscaphis japonica+Diospyros rhombifolia-Cardamine anhuiensis+Oplismenus undulatifolius （association Ⅴ）. The correlation and DCCA ordination results show that there are generally significant correlations of environmental factors （including elevation， slope， aspect， and slope position， etc.） with plant community structure and species distribution in Baohua Mountain， in which， elevation and slope are the important influence factors. With the decrease of elevation， increase of slope， and aspect variation from shady to sunny slope， association Ⅳ， Ⅴ， Ⅲ， Ⅱ， and Ⅰ are distributed successively with evidently vertical zonal distribution characteristics. Regarding dominant species in arbor layer， C. glauca， P. sheareri， and Meliosma oldhamii Maxim., etc. are the dominant species in high elevation area； while Liquidambar formosana Hance， Q. acutissima， and Acer henryi Pax， etc. require relatively low environmental conditions， thus have a wide distribution area； slope and aspect have a relatively great influence on the distribution of C. sinensis， P. adenopoda， and P. strobilacea， etc. The comprehensive analysis result shows that the MRT classification result is consistent with that of the DCCA ordination， that is， elevation and slope are the important environmental factors affecting the plant community structure and species distribution in Baohua Mountain. Deciduous broad-leaved forest in Baohua Mountain may transit to evergreen and deciduous broadleaved mixed forest， and gradually changes into typical zonal vegetation.