北京市建成区绿地植物物种来源分析

为探讨北京市建成区绿地植物的物种构成、外来植物组成及其在不同功能区的分布, 采用机械布点和随机抽样法对北京市建成区绿地植物资源进行系统调查。结果表明: (1)北京市建成区绿地植物外来引进种173种, 外来归化入侵种20余种; (2)外来引进种以国内引进为主, 境外起源物种中美洲和欧亚区系植物占绝对优势; (3)外来种丰度按大小排列为: 大型公园＞高等院校＞居住区绿地＞街头绿地/街心花园＞附属绿地＞街道绿地＞片林绿地, 而各绿地类型的入侵种数量没有显著差异。

Study on the Origin of Urban Plants in Built-up Areas of Beijing

To recognize the structural characteristics of urban green space, this study analyzed the composition and distribution of alien species in built areas in Beijing. We systemically investigated the plant sources using the method of mechanical layout and random sample. We found 173 alien species and approximately 20 invasive species in green-space areas of Beijing. Domestic introduced species constitute a great part of the alien s pec ies; the dominant ex otic plants originate from Central America and Eurasia. Some quantitative disparity of alien species exists for different green-space types, whereas the disparity of invasive species was indistinctive.