西安城市绿地植物多样性研究

发布时间：2018-05-05 13:19

本文选题：园林植物 + 植物多样性　；参考：《西北农林科技大学》2015年硕士论文

【摘要】：城市绿地作为城市生态系统的重要一环,在缓解城市生态系统压力、改善城市人居环境这些方面都能起到重要作用。而随着城市化进程的发展以及城市人口的不断增加,人类与生态环境之间的矛盾和冲突也日益加剧。其主要表现为城市中人类活动会对环境造成影响,从而导致城市植物多样性的不断减少,城市生态功能的下降。本文针对西安城市绿地的植物多样性问题,从西安市三环以内的公园、单位附属、居住区、广场、道路等不同类型绿地中选取了150个具有代表性的样地进行调查,从植物物种数量、重要值、生活型、丰富度指数、多样性指数、均匀度指数及乡土树种的使用情况等方面对西安城市绿地植物群落进行调查研究。分不同绿地类型探讨了西安城市绿地群落植物种类、多样性及生活型分布,并对比了不同绿地类型的植被情况。研究结果表明:(1)在调查范围内,共有树种176种,蔷薇科植物种数最多,有30种。其中乔木优势树种主要有女贞、银杏、国槐、雪松、油松、樱花等,灌木层优势种主要有女贞、小蜡、石楠、海桐、石榴等。(2)不同绿地类型的乔灌植物在种类分布、丰富度、多样性、均匀度上会存在差异性,主要原因在于植物群落的组成会根据绿地的不同功能及性质而发生适应性变化。(3)西安城市绿地乔木层Simpson指数、Shannon-Weinner指数、均匀度指数分别为0.648、0.980、0.893,灌木层的分别为0.456、0.891、0.512。其植物的Margalef指数、Simpson指数、Shannon-Weinner指数以及均匀度指数整体呈现乔木层灌木层的特征。(4)在西安公园绿地中,物种丰富度的大体是均匀与合理的,Margalef指数分布在1-1.5之间。Simpson指数和Shannon-wiener指数表现出的趋势大致相似。通过对比本次调查中公园绿地的多样性指数,公园的面积会对植物的多样性指数产生影响,公园面积与植物多样性指数呈反比。(5)西安城市绿地中乔木与灌木的物种数比值为0.56,常绿植物与落叶植物的比值为0.65。道路绿地中灌木的应用较多,尤其是常绿灌木(46.67%)的使用。乔木物种数比率较高的是公园绿地,常绿乔木和落叶乔木的比率分别达到9.76%和32.93%。在五种绿地类型中,道路绿地常绿与落叶植物的比值达到1.3,而公园绿地的比值最低(0.49)。(6)西安市乡土树种占全部绿化树种的55.5%,其中广场绿地最高(61.5%),道路绿地最低(50%)。西安市对乡土树种的应用还有所不足,应该加强西安市乡土树种的应用。本研究主要从植物物种组成、植物多样性和乡土树种运用三个方面对西安不同绿地类型的人工植物群落进行研究,可对今后西安城市绿化建设提供可参考的依据,这将对提高城市植物多样性、增强景观异质性和改善城市生态环境起到重要作用。
[Abstract]:Urban green space, as an important part of urban ecosystem, can play an important role in relieving the pressure of urban ecosystem and improving urban human settlement environment. With the development of urbanization and the increasing of urban population, the contradictions and conflicts between human beings and ecological environment are becoming more and more serious. Its main manifestation is that the human activities in the city will have an impact on the environment, which will lead to the continuous decrease of urban plant diversity and the decline of urban ecological function. In view of the plant diversity of urban green space in Xi'an, 150 representative plots were selected from parks, units, residential areas, squares, roads and other different types of greenbelts in Xi'an. The plant communities of urban green space in Xi'an were investigated from the aspects of plant species quantity, important value, life form, richness index, diversity index, evenness index and the use of native tree species. The plant species, diversity and life type distribution of urban greenbelt community in Xi'an were studied according to different types of green space, and the vegetation conditions of different types of green space were compared. The results showed that there were 176 species in total and 30 species in Rosaceae. Among them, the dominant tree species are mainly Ligustrum, ginkgo, Sophora japonica, Cedar, Pinus tabulaeformis, Cherry, etc., and the dominant species in shrub layer are mainly Ligustrum, small wax, heather, pomegranate, etc.) the species distribution and richness of different types of Arbor and shrub plants in green space. The diversity and evenness will be different, the main reason is that the composition of plant community will change adaptively according to the different function and nature of green space.) the Simpson index of Xi'an urban greenbelt tree layer is Shannon-Weinner index, the main reason is that the composition of plant community will change adaptively according to the different function and nature of green space. The evenness index was 0.6480.800.893and the shrub layer was 0.5120.4560.891. The Margalef index, Shannon-Weinner index and evenness index of the plants showed the characteristics of shrub layer of Arbor layer. The species richness is generally uniform and reasonable. The distribution of Margalef exponent is between 1-1.5. Simpson index and Shannon-wiener index show a similar trend. By comparing the diversity index of the park greenbelt in this survey, the area of the park will have an impact on the diversity index of plants. The ratio of species number of trees to shrubs in Xi'an urban green space is 0.56, and the ratio of evergreen plants to deciduous plants is 0.65. The application of shrubs in road greenbelt is more, especially the evergreen shrub (46.67). The percentage of evergreen trees and deciduous trees reached 9.76% and 32.93% respectively. Among the five types of greenbelt, the ratio of evergreen and deciduous plants is 1.3, while the ratio of green land in parks is the lowest (0.490.49) 55.5% of all green trees are native trees in Xi'an. Among them, the highest in square green space is 61.5%, and the lowest in road green space is 50%. The application of local tree species in Xi'an is still insufficient, and the application of local tree species should be strengthened. In this study, the artificial plant communities of different types of green land in Xi'an were studied from three aspects of plant species composition, plant diversity and application of native tree species, which can provide a reference basis for the construction of urban greening in Xi'an in the future. This will play an important role in improving urban plant diversity, enhancing landscape heterogeneity and improving urban ecological environment.
【学位授予单位】：西北农林科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S731.2

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