Urban-rural Ecotone Landscape Pattern Characteristics And Optimization Research Of Shanghai

Under the background of the urbanization that continues to develop rapidly,the urban-rural ecotone,as a transition zone between urban and rural areas,shows a dynamic change in its spatial distribution and internal landscape pattern.The research on the urban-rural ecotone has become a hot topic in related disciplines such as geography,ecology,planning and sociology.By analyzing the characteristics of landscape pattern,it is helpful to discover the characteristics of urban development expansion and ecological dynamic evolution,to understand the impact of economic and social activities on the geographical space,and to grasp the law of landscape ecological security.Which will provide the theoretical basis for the protection and planning of urban and rural construction management and landscape ecology.Shanghai,as a mega-city and a national economic center city,its urban-rural ecotone occupies an important position in the city's overall pattern and ecosystem and has a certain degree of representation in urban development in China.This study deeply analyzes the landscape pattern and optimization measures of urban-rural ecotone,and tries to put forward some countermeasures according to the urban development planning.With a view to providing ideas for revealing the characteristics,problems and countermeasures of landscape ecological security in suburban areas of China's big cities.The thesis consists of four parts:1.Using the methods of POI and kernel density analysis,and through the Google Earth imagery and NASA city night scene map verification,the distribution pattern of urban-rural ecotone in Shanghai are studied.The method breaks through the shortcomings of the traditional research methods based on the boundaries of administrative divisions and accurately reflects some fine features in the development of urbanization.Based on this,three typical patterns of urbanization expansion are extracted: the suburban circle expansion model,the middle rural axial extension model and the outer suburbs isolated development model.The influencing factors affecting the distribution of urban-rural ecotone are analyzed from the perspective of natural and geographical conditions,population concentration,planning orientation and traffic characteristics.2.Using Landsat8 image as the data source,through the methods of supervised classification and Fragstats landscape pattern index analysis,this paper interprets the landscape pattern of the urban-rural ecotone in Shanghai and analyzes the landscape pattern differences with the completely urbanized and rural areas.The results show that in the three types of areas,the urban-rural ecotone zone has the most extensive spatial distribution,the most complex shape features,and the most abundant landscape diversity,indicating that the area is greatly disturbed by human beings and the landscape pattern in the area is complex.The urban-rural ecotone has the largest area of farmland landscape.The water landscape in the urban-rural ecotone has a low dominance in the largest patch and a higher fragmentation.The shape of the residential landscape in urban-rural ecotone is relatively complex,and the degree of aggregation is low.Urban-rural ecotones,as the forefront of complete urbanization,have damaged natural patches such as green spaces and rivers,degraded service functions of ecological corridors,and the relationship between urban communities and rural communities.They should avoid any detours in landscape ecological function decline that the central urban area has ever taken.3.Taking into account the differences in natural factors such as history and geography and the driving forces of urbanization,sampling areas are selected for the three types of typical urban-rural ecotone in the city.Three typical models are extracted through further analysis of five major landscape elements of water,farmland,settlements,roads,and greenbelt.They are river-network low density mass type model,plain type high density spread type model,and coast high density stripe type model.The factors that form the three models have been discussed and summarized into three aspects: the ages of the lands,the artificial-natural landscape,and the differences in the methods of urbanization promotion.4.Based on the analysis of the overall landscape pattern of the urban-rural ecotone,combined with the requirements of the “Shanghai Urban Master Plan(2016-2035)”,this paper proposes the following suggestions: to optimize the basement advantages of farmland,accelerate the renovation of architectural patch,strengthen the construction of ecological corridors,and protect the diversity of landscapes.For the three typical models,ecological optimization measures for water,farmland,and settlement landscape types were proposed.Based on the characteristics of the typical pattern of urban-rural ecotone and the optimization ideas,an ecological assessment of the construction plan for a residential community developed in recent years was conducted,and the principle of ecological landscape optimization was used to propose an alternative ecological planning program.This paper uses POI and kernel density analysis methods to determine the spatial pattern of the urban-rural ecotone quickly and accurately,and analyze the causes for the formation of this distribution,it provides a new method for the research of the urban-rural ecotone.In addition,the use of landscape pattern index to interpret the typical model of the urban-rural ecotone on the mesoscale and the analysis of the impact of urbanization on the traditional rural settlement landscape are also innovative.