【作者】 吴丽娟；

【导师】 李俊清；

【作者基本信息】 北京林业大学 ， 生态学， 2006， 博士

【摘要】 城市生物多样性是城市生态系统的重要组成成分,在城市化日益加快的今天,与人类生存息息相关的城市生物多样性受到严重的威胁,城市生态环境质量不断恶化,人与自然关系、城市的可持续发展受到严峻挑战,加之城市生态系统的复杂性,城市生物多样性问题成为近年来生态学研究的热点和难点。本文研究区域为北京城市化程度最高、人口最为密集的五环路内城市绿地。根据实地调查和资料收集的数据,采用定量定性相结合的分析方法,应用GIS技术,对五环内城市绿地生物多样性现状、城市绿地景观格局等进行了全面系统的研究分析,在此基础上,提出北京五环内城市绿地生物多样性保护与发展规划方案。北京五环内绿地共有维管束植物102科,325属,559种(包括变种、变型及品种),占北京维管植物总数的1/4;有外来入侵植物12种,国家级保护植物2种;北京乡土植物308种,占五环内植物总种数的55.1%,国内引进种144种,国外引进种107种;野生乡土植物有237种,占五环内植物种数的42.4%,其中草本植物216种,多以杂草形式存在于城市绿地中,城市绿化潜力很大。植物种类组成分析表明,北京城区植物以乡土植物为主,但引进种也占有较大比例,在城市绿化中发挥着重要作用。绿地植物种类构成分析比较得知,公园绿地物种丰富,附属绿地次之,道路河岸绿地最少;附属绿地的乔木层、灌木层丰富度指数最高,公园绿地草本层丰富度指数最高;道路绿地整体植物多样性偏低。通过绿地树种优势度比较,各类绿地均为少数树种占绝对优势,排在前十位乔木树种应用量累计均超过65%,排在前十位灌木植物应用量累计均超过70%,且不同绿地的优势树种种类多数相同,造成绿地树种单一、结构简单,景观相似。各环带绿地总体物种多样性指数大体上呈现由2环内到4-5环逐渐升高的趋势;乔、灌、草植物多样性指数也是由2环内到4-5环基本呈逐渐升高趋势;物种丰富度指数呈现出草本层>灌木层>乔木层的特征;物种的均匀度指数是乔木层>灌木层>草本层。乔木、灌木植物种数没有草本植物多,但因其分布相对较为均匀,表现出较高的多样性指数,草本植物数量大,但少数物种起主导作用,多样性指数不高。五环内共有18470个绿地斑块,总面积为11023.29公顷,平均绿化覆盖率为更多还原

【Abstract】 Urban biodiversity is one important component of urban ecosystem. Along with the rapid urbanization in recent years, the urban biodiversity which is closely related to human beings has been seriously threatened. The quality of urban ecological environment is getting worse. The relationship between human and nature, and the urban sustainable development is being challenged. Research on urban ecosystem which is complicated has become a hotspot and difficult task in recent years.The focus of this research is the greenbelts within the 5th circle road in Beijing,it is an area which has been highly developed with intensive population. The research explores field study and data collection, uses quality and quantity analysis methods and GIS techniques to illustrate the whole picture of current situation of urban biodiversity and the greenbelt landscape pattern within the 5th circle road. As a result, the greenbelt biodiversity conservation and sustainable development plan for the area within the 5th circle road in Beijing has been developed.Main research results are as follows:According to the urban floral category, there are 559 plant species in total which belong to 102 families and 325 genus in the greenbelts within the 5th circle road in Beijing. Among them, there are 10 alien species, 2 state protected species, and 308 native species which accounts for 55.10% of the total plant species within the 5th circle road. There are also 144 domestic introduced species, 107 abroad introduced species; 237 native wild growing species, which occupy 42.4% of the total plant species in the area. Among these species, 216 are herb plants, most of which grow as weeds in the urban greenbelts these species shows great potential for afforestation. The research indicates that the majority of greenbelt plants are native species while and the introduced species also account for a big proportion.After comparing the composition structure of plant species in greenbelts, we find that the greenbelt in parks have the richest diversity, followed by subsidiary greenbelts, the road and water system have the least plant species. The tree and shrub layers in subsidiary greenbelts have the highest diversity index; while the biodiversity is lower in road greenbelt system; grass layer of the greenbelts in parks have the highest diversity index. Based on the comparative results of dominance degree of tree species in greenbelts, it proves that few tree species are absolutely dominant in all kinds of greenbelts, the更多还原