Studies On The Theories And Practice Of Ecological Construction For Urban Green Space

Urban green space is a subsystem of urban compound ecological system—the only subsystem capable of production and self-adjustment. During the construction of eco-city, an important issue is to build a complex green space system. This system should not only have a high green space index, but also a proper layout with a combination of all levels to constitute a perfect compound green system. Urban green space should accord with urban ecosystem, following the urban green space self-development rules. At present time, great achievements have been made in the study and development of urban green space. But it is still lacking in systematic theoretical framework and guidelines, and a thorough research is to be carried out in various aspects including the connotation, the system information, ecological planning, management, and ecological construction of urban green space, etc.This dissertation clarifies the connotation of urban green space and scientifically summarizes the taxonomic system and the development history of the urban green space. Based on these aspects, the frame of a new urban green space theory has been established, directed by urban ecology, landscape ecology, restoration ecology, urban planning, and environmental science, etc. Through these researches, an approach of urban green space ecological construction has been attained. Meanwhile, it also presents a case study of Shanghai as a cosmopolitan city.This dissertation consists of three parts:In Part I, the development procedures of urban green space are introduced through a research on the background of ecological construction for urban green space. The author holds that the present urban green space has entered the phase of ecological construction. By analyzing the study of urban green space at home and abroad and its existence conditions, the author brings forth a much higher and more systemic requirement of the fixed quantify research about urban green space and new technological applications such as landscape ecology, GIS, RS, GPS, etc. The development procedure of urban green space ecological construction has been arranged in order. The author also points out that it is a trend that urban green spaceecological construction research would be quantified, systematized and multi-techniques applied as well.The concept of urban green space and its present taxonomic system have been clarified and expanded. The system is divided into nine categories. Due to the present development of urban-rural integration, farmland, wetland and urban forest have become important components of urban green space. The ecosystem service of urban green space has been expounded, and thus the conclusion that it should have an integrated function of nature, economy and society.The dissertation sets up the framework of urban green space science, differentiating and analyzing the scales of urban green space its connection with related concepts. According to the new concept system, the dissertation launches a theoretical research framework specifically designed for the urban green space science. It also elaborates on the research contents of urban green space science and the subject attribution. Through the framework, the dissertation systematically probes into the ecosystem service of urban green space, analyzing the eco-city and ecological construction etc. The compound connotation of urban green space ecology has been expatiated systematically through the application of urban ecology and the landscape ecology, etc. Then the dissertation points out that the urban green space ecology construction ought to comply with the rules of ecological balance, niche and mutualism. Based on ecology and landscape ecology, the ecological construction for urban green space contains the three levels of urban green space, community and species, thus creates an approach of ecological construction for urban green space.In Part II, through positive research, a regression model for direct value of urban green space has been established, calculating the direct price of Shanghai ecosystem service. A conclusion is reached, i.e. the eco-value of Shanghai urban green space increased consistently from 1995 to 2004 through the evaluation on air clearance and climate adjustment of urban green space. In 2004, the direct value of ecosystem service was ￥19.8138 billion, the indirect value of was ￥169.5267 billion, and total value of ecosystem service was ￥189.3405 billion. The Gray System Model of G (1, 1) has been applied to predict the ecosystem service value of Shanghai urban green space in 2010, which will be ￥323.211 billion. In the index value, the III grade index system has been constructed from economics, society, and the construction of urban green space, as well as its function and landscape. The evaluation results of Shanghai indicate that integrated index value is 0.52, belongingto the lower upper II grade.The dissertation analyzes the landscape characters, the diversities and the broken indexes of urban green space in Shanghai. The space landscape distribution of urban green space in Shanghai was analyzed according to the Models of Space Self-correlation and Geographical Statistics. During 1979-2004, the index of landscape similarity decreased, the broken index increased and the urbanization was boosted as well.The dissertation analyzes the arrangement features of urban green space in Shanghai, comparing the diversified communities of artificial green space, the factorial green space and the secondary vegetation.This research states that the higher the compound extent of communities is, the higher the diversities are. It cites the natural forest in Pudong New Area as an example to show the actual approaches applied in improving the biological diversities.In Part III, the current problems have been stated from various aspects including the value of ecosystem service, the landscape pattern, and the urban green space construction of communities, and corresponding measures are proposed: the construction of urban green space in Shanghai should be managed comprehensively by optimizing the community structure, adjusting the landscape pattern and enforcing relative laws, etc.