Tangshan Urban Ecosystem Health Appraisal Research

Urban ecosystem with the urban residents'living and produce for center is artificial ecosystem, which is composed of the nature, the economy, the social three subsystems. However, following the fast innutrition and urbanization, large amount of people living in the cities, which brings the resource exhaustion, environmental pollution and ecological destroy etc. As a new subject,many aspects of ecosystem health are in the seedtime. Especially for urban ecosystem health, there aren't a mature system info and evaluation methods. This paper on the base of correlation research findings, taking Tangshan urban ecosystem for example, explore urban ecosystem health analysis deeply though the theory, methodology and practices.On the basis of concept, characteristic, structure,the article is discussed the intention of urban ecosystem, summed up healthy connotation, introduced the assessment methods briefly. Simultaneous, uniting urban ecosystem health appraised theory , building index system of urban ecosystem healthy appraised, it include the natural, economy and society subsystem tripartite , 27 indices together. Taking Tangshan for example, having estimated that objectively that time series valuation and the space array valuation is appraised.The time series carry out valuation by distance -harmonize model. Ascertaining the healthy target value and ill-condition according, calculates every index distance exponent, ascertain weight of every index by mean square, ascertain health index of every subsystem by linearity, calculate coordination index of every subsystem by CV. Space carry out valuation by blurred mathematic model. Set Tangshan , Xingtai and Langfang for appraising marriage partner, ascertaining the weight matrix by factor analysis, building the relative subordinate degree matrix, forming synthesized maluation matrix finally. Corresponding to the result find out the restraint factor of Tangshan urban ecosystem healthy, and having suggested that optimization countermeasure goes to improve the Tangshan urban ecosystem.The article compared and assessed by direction (time series) and lateral (space array), analysis the situation of Tang Shan City urban ecosystem health from the 2001to 2005, Simultaneous, contrasted Tang Shan urban ecosystem health situation with Xing Tai and Lang Fang in 2005. Calculating out health index of Tang Shan City from 2001 to 2005, the coordination attaching importance to every subsystem applies harmonizing an exponent indicating every subsystem's harmonizing degree to healthy effect of city ecosystem. From the city calculating result perceiving Tang Shan City urban ecosystem health indicating Tang Shan City from 0.078 to 0.468, the ecosystem displays the year by year healthy developing trend. Middle apply blurred mathematic model to transverse direction contrast having avoided subjective the value dividing the healthy target value and ill-condition, the objectivity having laid stress on result. Building the relative subordinate degree matrix, health is contrasted with every index and every city, reflecting the urban ecosystem health of Tang Shan City objectively more. The Urban ecosystem health appraising matrix of Tangshan, Xingtai, Langfang is {0.618 , 0.188 , 0.725}, according to maximal subordinate degree principle, three cities as follows: Langfang> Tangshan> Xingtai.