The Ecological Security Synthetical Assessment In Min-jiang Watershed

Eco-security as a newly arisen disciplinary field has been gained much attention presently, and watershed has been its important research scale. In this paper, a case of Min-jiang Watershed (MTW) ecosystem is investigated with comprehensive methodologies integrated by Ecology, Environmental science, Management science, Geography and Sustainable Development theories, we develop a System of Assessment Index derived from analysis of the stressing factors of ecological security issues and their formation mechanism of MJW in order to figure out its sensitive factors for further comprehensive assessment of its eco-security and finally to propose the strategies and countermeasures for its long run eco-security in terms of the perspective of Watershed Integrated Management. In general, six issues concerning Eco-security of MJW are addressed in the paper, including:First, A general research route by overviewing the research status, advance and theories on the fields.Second, A summary analysis of main stressing factors of Eco-security problem of MJW by probing the physical geography and the socio-economic status of MJW.Third, A integrative framework for MJW eco-security assessment, including the methodologies and models, evaluating indices and their weights respectively by emphasizing the principle of Constant Weight and Variable Weight.Fourth, An Index System for MJW Eco-security assessment and its analytical outcome as thecore results of the present research that are characterized respectively as following :(1) To develop an Index Syetem for MJW Eco-security assessment hierarchically both by screening the sensitive index based upon PSR( Pressure - State - Response )model framework and applications of AHP ( Analytic Hierarchy Process ) and PCA ( Principal Component Analysis ) , it contains 25 indexes (the Pressure subsystem with 10 indexes, the State subsystem with 8 indexes, and the Response subsystem with 7 indexes).(2) To retrace analyses of the degree and level of Eco-security degree of MJW in 1990 and 2004 exploring above Assessment Index Syetem and further integrating model of Aggregating Index and Grey Relation with Constant weight and Variable weight methods to differentiate counties within MJW, the results indicate that the Eco-security of most counties within Watershed were between the class III to the class IV, remain alert status and some counties even in the middle-alarm status always, even worse, the eco-service of a few counties within MJW have been degenerated, the whole situation of eco-security in Minjiang Watershed can not be optimistic.(3) The calculation result of Variable Weight-Grey Relation model is adapted to analyse the tendency of Eco-security Dynamic Degree. The results show that besides the Eco-security Degree of Guangze, Wuyishan, Jian-ou, Yong-an and Ninghua is declined, the remaining counties increased with a little amplitude between 1990 to 2004; In Guangze, Jian-ou, the Eco-security Degree is descended obviously, correspondingly, the amount is increased remarkably in Dehua. Fuzhou urban district, Taining.(4) To device Contributing Amount and Obstacle Amount of Indices that determinate the Eco-security of MJW exploiting calculation by Variable Weight-Grey Relation model. The results imply that each index can be an impedient factor to eco-security of the counties within MJW; The impedient factor of different county in different years are different ; The Obstacle Amount of most index that ranking the first to certain counties within MJW is more than 10%; There are different regional specific characteristics in 2004, each branch has its impedient factor.Fifthly, A discussion on the driving mechanism for the change of MJW Eco-security based on the quantitative analysis previously combing the dynamic analyses of land use / cover, forest ecosystem and socioeconomic system.Lastly, A regulating and control systems for safeguarding Eco-security of MJW by addressing the integrative management of watershed ecosystem afterwards with the problematic analyses of the current watershed management model. Such systems including the administrative & concerted, legislative & supervisory, planning & implementary, ecologically compensatory, technologically supportive, public participatory, financially assuring, ecologically restorative & remediating.