【作者】 曾毅；

【导师】 周志翔；

【作者基本信息】 华中农业大学 ， 园林植物与观赏园艺， 2010， 硕士

【摘要】 近几十年来,随着工农业的迅猛发展,人口的大量增加和城市化进程的不断加快,我国的城市湿地正面临着区域生态环境破坏、自然景观消失、生物多样性减少、生态系统功能丧失等多种生态灾难。因此,恢复和重建湿地生态系统,创造良好湿地生态环境,维持湿地生态功能,具有其重要性和必要性。作为湿地生态系统的三大基本要素之一,湿地植物的恢复对于湿地的保护和生态恢复具有至关重要的意义。本文在武汉市25个典型城市湖泊湿地高等植物调查的基础上,采用TWINSPAN分类与DCA排序相结合的方法分析了严东湖植物群落的类型和结构,综合文献研究的成果提出了武汉城市湖泊湿地植物群落恢复的参照目标。通过武汉城市湖泊湿地植物退化状况分析,划分了城市湖泊湿地的退化类型,分析了各类型的退化原因以及优势物种的分布与干扰的关系。评价了湿地植物种的应用价值,并在各类湿地中选取植被退化严重的典型湖泊,在湿地植物群落现状分析的基础上,提出了其植物群落恢复模式,以期为武汉市乃至相邻地区城市湖泊湿地植被恢复提供依据。主要研究结论如下：(1)适度干扰下的严东湖与梁子湖(1998-2002年)、东湖(1992-1993年)湿地植物群落分析揭示了武汉市湖泊湿地地带性植物群落的组成和结构,可作为武汉地区典型的湖泊湿地植物群落类型,为植被恢复提供参照。(2)武汉城市湖泊湿地植被普遍存在退化现象,主要表现在物种丰富度不同程度地降低、优势种类发生变化。根据植被退化程度和原因将受到强烈干扰的典型湖泊湿地分为强人为活动干扰型、人为活动+渔业养殖干扰型、围湖造陆+污水排放干扰型、强渔业养殖干扰型、污水排放+人为活动干扰型、湿地生境旱化+污水排放干扰型等6种类型。(3)湖泊湿地周围的土地利用方式、湖泊功能、水位波动范围、湖岸的形式、水质类别以及水体污染物的种类等因素会对大部分湿地优势植物种的分布产生一定的影响。此外,武汉湖泊湿地植物原有的生境越来越趋于破碎化,小的湿地斑块彼此之间没有连通,物种的繁殖和扩散过程被阻隔,这些人为作用对湿地植物分布的间接影响也较大。优势植物种分布格局的分析将为湿地植物群落恢复模式构建过程中的种类选择与结构配置提供依据。(4)分析了282种武汉地区乡土湿地植物种的生态适应型,筛选出了具有净化水体、观赏、保持水土、经济生产等突出应用价值的功能种类。喜旱莲子草(Alternanthera philoxeroides)、北美车前(Plantago virginica)、野老鹳草(Geranium carolinianum)、一年蓬(Erigeron annuus)、野胡萝卜(Daucus carota)等外来物种在武汉城市湖泊湿地的分布非常广泛,并且在群落中占有一定的优势,表明湖泊湿地环境改变,原生的植被遭到破坏。有些外来物种已经在本地归化或广泛栽培,不具有入侵性,也基本未对原生植被和环境构成危害,可以视其优良性状适当选用。(5)基于湖泊湿地植被的退化原因和湖泊的规划功能,从植被退化严重的6类湖泊中各选择一个湖泊湿地作为典型模式营建的场地,以原有的湿地植物群落为基础,结合植物种类特性分别构建了经济生产型、景观美化型、生态保护型、综合效益型等多种湿地植物群落模式。这些模式可在湖泊湿地植被恢复实践中根据植物群落退化状况及功能要求选择应用。更多还原

【Abstract】 In recent decades, urban wetlands in our country are facing the regional ecological environment being destroyed, the natural landscape vanishing, the biodiversity reducing, the ecosystem function getting lost, same like those kinds of ecological disasters along with rapid industrial and agricultural development, population increase and urbanization process acceleration. Therefore, recovery and reconstruction of wetland ecosystems, thus creating favorable wetland ecological environment and maintaining the ecological functions of wetland is important and necessary. As one of the three basic elements of wetland ecological system, wetland vegetation restoration would play a vital role in the wetland protection and ecological restoration. On the basis of higher plants investigatation of 25 urban lake wetlands of Wuhan city, the type and structure of Yandonghu lake wetland higher plant communities were studied using TWINSPAN and DCA. Combining with literature comprehensive achievement, the reference target of Wuhan lake wetland vegetation restoration was presented. Through analyzing plant degradation status, the 25 lake wetlands were classifiedThen the causes of various types of degradation and the relationship between distribution of dominant species and disturbance were studied. The wetland species’s application value was evaluated. One lake was selected from each class of severe degradation lakes, and the status of plant communities were analyzed as the basis. Then the corresponding restoration models were put forward, which would provide reference to vegetation restoration of this region and adjacent area. The main conclusions are as follows:(1)The plant community types, composition and their structure in Yandonghu Lake which had get moderate disturbance, Liangzihu Lake (1998-2002a) and East Lake (1992-1993 a) wetland had been revealed as the typical of Wuhan’s, which would provide reference for the vegetation restoration.(2) Mainly displayed in the form of species abundance reduction on varying degree and the dominant species changement, the degeneration phenomenon of Wuhan urban lake wetlands is quite common. According to the vegetation degeneration degree and reasons, the urban lake wetlands which were subject to intensive disturbance were divided into 6 kinds, including intensive human activities’disturbance type, human activities & aquaculture interference type, wetland invading & sewage disposal interference type, intensive aquaculture interference type, sewage disposal & human activities disturbance type, wetland habitat aridity & sewage disposal interference type. (3)Land use around lakes, Function of lakes, Shoreline features, range of water level fluctuation and water quality had some relationship with the distribution of wetland dominnat species. In addition, the original habitat of wetland plants in Wuhan urban lake tended to become increasingly fragmented and small patches of wetlands could not link with each other, so species reproduction and diffusion process were been cut off or blocked. These kinds of artificial effects on the distribution of wetland plants are also great. The analysis of dominant species’ distribution pattern would provide criterion for species selection and structure configuration during the process of plant restoration model construction.(4)The application value such as water cleaning, ornamenting, water and soil conservation, production and economic value and the ecology ecad of 282 native plant species of Wuhan was assessed. Several exotic species, such as Alternanthera philoxeroides, Plantago virginica, Geranium carolinianum, Erigeron annuus and Daucus carota etc. were distributed widely, and dominant in the communities. It demonstrated the environment of lake wetlands had changed and native vegetation had been destructed. Certainly, there were also many exotic species which had been locally naturalizerd or widely cultivated did not hazard the original vegetation and environment, so they could be appropriately applied depending on their good traits.(5)6 lakes were selected according to the reason of vegetation degeneration and plan function of them, as the sites constructing restoration models which were based on the existing community types and composition, plant species characteristics and relationship. The productive and economic model, the landscaping model, the ecological protection model and the comprehensive efficiency plant community model were constructed. These models could be applied under the condition of plant community degetation and functional requirements of the lake wetland vegetation restoration.更多还原