Study On Changsha Urban Forest Based On Building A Resource-conserving And Environment-friendly City

With the rapidly development of worldwide urbanization and population growth,it resulting a series of ecological problems of the city such as urban heat island effect,air pollution,acid rain,water pollution,noise pollution,that had been a serious threat to the survival and development of urban residents. There is an increasing awareness of the importance of the ecological environment construction. As an important part of urban natural-economic-social complex ecosystem, which has self-purification function, urban forest plays an irreplaceable role to other infrastructure in protecting of human health, regulating the ecological balance and improving the quality of the environment, beautifing the urban landscape, and so on. Therefore, since 1962 the Government of the United States John F Kennedy outdoor survey reported and used the word of "urban forest", it has taken more and more attention to the countries.People from different disciplines in terms of urban forest in-depth research and evaluated it.In this article, on the basis of analysis a large number of literature at home and abroad, combined our country's goal with two types of social construction, with "Study on Changsha Urban Forest Based on Building a Resource-conserving and Environment-friendly City " for the title,gave depth analysis and research in the development of urban forest in a Resource-conserving and Environment-friendly society (two types of society)of China, put forward a set of evaluation index system and evaluation criteria based on two types of urban construction,and conducted the empirical study, and carried on the concrete study to Changsha urban forest present situation and the future.This is a new awareness of the relationship between city and nature, as well as two types of urban development, such as, for guiding the construction of Changsha city and its urban forest and two types of social coordinated development, have a certain reference value and practical significance. The main conclusions are as follows:(1)The urban forest is the important foundation of natural ecology which two types of society construct, has the pivotal function particularly to two types of urban development.(2)Uses the method which expert grading and the analytic hierarchy process (AHP) unifies to obtain various floors of the importance of comprehensive evaluation indicators. The result indicated that in the construction of urban forest development level of 36 index factors, urban air quality rate importance was largest, has achieved 15.56%, followed by the drinking water quality standards and urban forest naturalness, has achieved 9.44% and 9.15% respectively.It is showing that in the two types of urban constructions, urban forests must firstly play an important step is to develop the ecological functions such as improve air quality, ensure ecological security of urban water source, at the same time need to make reasonable arrangements of urban forest structure and layout, enhance the urban forest naturalness, form the urban forest self-succession process. (3)It has determined the baseline value in the urban forest evaluation of the current two types of urban construction.(4)According to the evaluation results of the urban forest evaluation system the institute established, Changsha urban forest quality synthetic evaluation value is 0.7788 in the two types of urban constructions in the final, at the first level III to the level II phase transition, which can be seen a self-sustaining urban forest level.It indicated that Changsha urban forest still have certain distance with two types of urban construction's request. The main problem is the existence of urban forest structure and economic value are to be improved, mainly with the urban forest coverage of protected areas, landscape open space, species abundance as well as network of forest belts, of rivers and lakes, of forest belts road, combined in low degree. In addition, the city forest conservation personnel quality level is not ideal.(5)It has carried on the dynamic appraisal to Changsha city forest, and estimated that to the year of 2014 and 2020, Changsha urban forest evaluation is 0.8303 and 0.8643 respectively in the two types of city construction, will achieve the primary of levelâ…¡and advance stage in two types of urban appraisals, and gradually to phase level 1.Lights of this article:(1) This research takes foundation for the synthesis of the existing urban forest indicator system results, applies some theories and methods of other discipline's in the urban forest valuation target calculations,and has established a comprehensive evaluation index system,which covering natural ecology-economic development-social development of the multi-factor in two types of social urban forest.(2) It tooks 36 evaluation indicators in the indicator system in all, including urban forest quantity control, structure, function requirements of the 21 indicators; including the economical investment, the value deliver of 5 targets; including the social heavy visual degree, including the harmony between man and nature of 10 targets. It achieved omnidirection and quantify of the evaluation in the construction of two types of urban forest.(3) The construction of two types of urban forest valuation indicator system and empirical research,that can re-understanding functional of the urban forest in new conditions. Changsha City were evaluated by the made indicator system. The results of paper not only provide data for Changsha city to build two types of urban forest construction planning of, rational development and utilization of urban forest, but also have an important reference value for the two types of society.(4) It has carried on the dynamic appraisal to two types of urban forest construction,and provided the direction to the future.