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为探讨不同类型植物群落改良土壤的功能差异，进而为城市森林的群落构建与管理提供科学依据，以上海环城林带7种典型植物群落为对象，以裸地为对照，分层测定了土壤的密度、毛管孔隙度、总孔隙度、有机质、全氮、全磷、铵氮和硝氮等8个理化指标，并采用主成分分析法进行各群落类型间土壤质量的综合评价。结果表明：植物群落对土壤的改良作用主要表现在土壤表层（0～20 cm），不同植物群落改良土壤理化性质的效果存在差异，落叶阔叶林悬铃木群落和落叶针叶林池杉群落的土壤质量指数较高，而落叶阔叶林全缘叶栾树群落的最低，其他类型群落的居中，不同植被类型间并没有表现出明显的规律性。可见，减少人为管护有利于枯枝落叶层的积累及林下草本和幼苗的更新，可以促进土壤质量的综合改善。“,”To explore the soil improvement service of plant communities, and provide a scientific basis for urban forest planning and management, soil samples were collected from seven plant communities in Shanghai green belt with bare lands as the control. Eight soil physical and chemical indicators were measured in different soil depth, including soil bulk density, capillary porosity, total porosity, organic matter, total N, total P, NH+4-N and NO-3-N. Principal compo?nent analysis was used to assess the comprehensive soil quality based on those indicators. Results showed that soil im?provements were mainly on the surface of soil ( 0-20 cm) , with different soil improvement effects of each plant commu?nities. Deciduous broad leaved forest with Platanus×hispanica as dominate species and deciduous coniferous forest with Taxodium distichum var. imbricarium as dominate species had the greatest improvement effect, deciduous broad?leaved forest with Koelreuteria bipinnata var. integrifoliola as dominate species had the least improvement effect, and the other communities were in the middle level. Lower?intense?management was helpful to litter layer accumulating, and facilitate the recruitment of understory seedlings and herbs, which could contribute to the overall improvement of soil quality.