Combining the method of French-Swiss schools and that of British-American schools, species composition, diversity, frequency, regeneration patterns of different communities and structures, limitation factors of understory woody plants in the artificial plantation of Shanghai central city and the Green Belt were studied from 2007 to 2009 in 908 plots. The result showed that: ① The species richness in understory layer were much more abundant than in the upper layer, the species diversity of the needle broad-leaved mixed forest and the mixed evergreen and deciduous broad-leaved forest were much higher than the other community types, and so did the tree-shrub-herb structure and the tree-herb structure compared with the shrub-herb structure. ② 101 woody plant species were detected in the regeneration layer including 33 evergreen species and 68 deciduous species; only 36 species which mainly composed of deciduous broad-leaved trees and native species had the frequency of more than 1 % ; Ligustrum lucidum and Cinnamomum camphora appeared in more than half of the communities,the rates of frequency are 58. 6% and 53.7%, respectively. ③ It was suggested that the seed sources and dispersal, light intensity, the soil moisture and the coverage of the regeneration layer were the key limitation of understory vegetation regeneration.%以上海市中心城区和外环绿带人工林为对象,于2007-2009年采用法瑞学派调查法和每木调查法相结合,共计调查典型样地908个,测定记录林下更新层木本植物的种类、数量、盖度及其生境特征,分析更新层物种组成及出现频率、不同群落类型及结构特征,并探讨影响其多样性格局的主要限制因子.结果表明:①人工林样地更新层木本植物丰富度普遍高于林木层,针阔混交林和常绿落叶阔叶混交林更新层多样性较最高,乔—灌—草结构和乔—草结构更新层物种多样性高于灌—草结构；②林下更新层共出现木本植物1 01种,占林木层总种数的65.1％,其中常绿树种33种,落叶树种68种,出现频率≥1％的有36种,生活型以落叶阔叶乔木为主,乡土物种占75％,女贞(Ligustrum lucidum)和香樟(Cinnamomum camphora)出现频率最高,分别为58.6％和53.7％;③种源、种子散布方式、光照强度、土壤湿度和草本层盖度等生境因子是人工林林下自然更新的主要限制因素.
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