China's Urban Forest Theory And Empirical Research

In the research and development of urban forests, China has made great achievements but hasn't had the systematical theory yet to generalize the practices, and still is urgently expected to have an in-depth study in the connotation, classification, and management, etc. of urban forests.This dissertation aims to four main objectives — to clarify the concept of urban forest, to establish a research framework and construct a system of urban forestry, to develop an evaluation method and its information- support system for urban forest. This paper, with the leading of multidisciplinary theories in urban ecology, landscape ecology, forestry, and environmental science study, etc, makes an in-depth study on the references and data of the research and practices of urban forests in China by following systematical thinking and the integrated research method of theory and practice combined with the 3S and computer techniques.In section one, by introducing the background of urban forests theory, the research history at home and abroad and the thinking resources, this paper makes an arrangement for the developing routes and hereby a comment on the present internal and oversea research dynamic of urban forests.The section two first compares and analyzes many explanations on the concept of urban forest in different countries, and then systematically clarifies the complex connotation the concept of urban forest with the principles of landscape ecology. It considers that urban forest should be understood from three different scales: urban forest system, urban forest community patch, and urban forest individual plant. The paper clarifies the range of the urban forest and its relationship with related concepts. According to the new concept system, a theoretical research framework which links to the key questions of urban forestry is built, and the research content of urban forestry and the features of the academic subject are also given an explanation.Based on the study framework of urban forestry, this dissertation gives a systematic research on the surviving and developing rules of urban forest. The question of ecosystem service of urban forest and how to evaluate and manage it are studied as well. All of these studies are presented respectively in section three, four and five, which altogether compose the theoretical system of urban forestry.The section three is about the theoretical and empirical study on the urban forest classification, individual plant, and community and urban forest system. In this part, a classification system for urban forest is offered. This paper also discusses the growth and development law of the trees and communities of urban forest and puts forward the concept of near-natural urban forest community. Through any examples, the method of urban forest construction is explored as well. Subsequently, by the examples happening in shanghai, the paper also makes analyses of the characters, the dynamic mechanism of urban forest system and the control method in planning. This section applied the statistical method on the detail study on the antipollution plant resources of China for urban forest. The conclusions include: China is rather abundant in antipollution plant resources with enormous potential to explore and utilize which has a high diversity degree and to be specialized in some natural taxon particular families at the same time; the anti-sulfur-dioxide effect is among the most widely found ones; the proportion of anti-chlorine plants in south China is higher than that in the north, but the proportion of anti-hydrogen- fluoride plants are lower than the other two areas; the plants with wide ecological breadth always have a wide antipollution spectrum too; the plants with both wide ecological breadth and antipollution ability always are common species in greening utilization. A checklist of antipollution plants for urban forest in China is presented as an addendum to the chapter six.In section four, in combination with the analyses of urban ecosystem services, the paper mainly focuses on the problem of what is embedded on the ecosystem services, its general characteristics, and the interrelationship between the urban ecosystem and therefore the services it supplies. In addition, the detailed analysis about the mechanism of the development of urban forest is discussed from the main six kinds of ecosystem services.The section five conducts the research on the evaluation and management system for urban forest. It develops a comprehensive evaluation indicator system, which consists with 16 indicators through the application of SSMII, K.J, and AHP-Delphi, etc. Based on the evaluation system, an Information Support System for Shanghai Urban Forest Comprehensive Evaluation (ISSFSUFCE) is developed using VB and ArcObjects. ISSFSUFCE realizes not only the evaluation function but also the sampling services and the map support for data collection. Applying this system to the evaluation on Shanghai urban forest proves that the Shanghai forest is relatively satisfactory in harmony, but its ecological structure need to be improved. The lowvalue of the comprehensive Urban Forest Index (UFI) implies that there should still be a long way to go before the ecosystem services could function perfectly. The research on the management of urban forest in this part focuses on six aspects. The first one is on the content of the management that is composed of resources, construction, maintenance, business running, and the scientific-technological support of urban forest. The second is the implementer of the urban forest management including the special department of the government, social groups, investors, and the citizens. And the other four aspects are about administration structure, target, method and technique of urban forest management.