Research On Coastal Ecological Security Based On OWA-GIS Method

Maintenance of regional ecological security is not only the foundation to promoteharmonious relationship between human and land, but also an important guarantee toachieve sustainable development. Because of abundant resources and unique geographicallocation, coastal areas have experienced a huge development in economy in china. With thefeature of fragile and sensitive, they locate in the interlaced zone of land ecosystem and seaecosystem. However, the structure and function of coastal ecosystem has been damagedunder the press of high-intensity human disturbance and a series of knock-on effect. Theecosystem has been suffered imbalance state, which has been a serious threat to humansurvival and development now and then. It is generally acknowledged that the coastal areaopposes the fastest speed of economic development in the Liaoning province and even tothe whole northeast in china. At the same time, the problems, such as environmentalpollution, shoreline retreat, seawater intrusion, soil Stalinization, which might be resultedfrom rapid urbanization and industrialization, can not be ignored. Therefore, the research ofdiagnosis of the health degree of the coastal ecosystem to ensure regional ecologicalsecurity is imminent. Taking the yellow sea coastal region in Liaoning province as the studyarea, the paper has combined OWA (order weight average) multi-criteria decision-makingmethod and GIS in order to explore eco-security assessment and prediction with the help ofArcGIS and IDRISI technology platform. The main content of the research include threeparts as follows. First and foremost, coastal city ecological security evaluation index systemhas been build on the basis of analyzing the driving mechanism from four aspects, which isnatural ecological security, resources and energy security, coastal environmental safety,social economic security. Then, evaluation index data has been gained based on TM image,DEM data and statistical data. Meanwhile, vector processing and standardization gradinghas been realized by means of ArcGIS platform. Last, index weight and order weight havebeen calculated by using the rules of analytic hierarchy process (AHP) and the method offuzzy quantitative respectively by IDRISI. The eco-security evaluation under a variety ofrisk decision level has been carried out with integration the standardization layer and the indexes weight by using OWA function. Ecological security situation of seven risk attitudeshave been calculated, which the risk coefficients are0.0001,0.1,0.5,1,3,10and1000. Theresult shows that under the different risk coefficient, policymakers focus on different things;ecological security evaluation results are also different. According to the actual situation,decision makers risk attitude and evaluation purpose, different evaluation results should betaken into consideration. When policy makers pay more attention to the social andeconomic security and less concern about the natural ecological security, meanwhile theyare willing to bear high risks; they may prefer to choose the eco-security evaluation resultswhich risk coefficient is0.0001and0.1. When policymakers believe that natural eco-security,resources and energy security, environmental security, social-economic security are equallyimportant, then they are inclined to select the evaluation of risk coefficient is1.If policymakers place more emphasis on resources and energy security and natural ecosystems safety,and do not ignore the influence of ecological environment quality, choosing the results withrisk coefficient is3might be an advisable choice for those who trend to avoid risk. Whendecision makers pay special attention to natural ecological system and take a littleconsideration of socio-economic factors without considering environmental factors andresources carrying capacity, the evaluation results with little risk is the best decision.Though it is the least risky decision, the eco-security evaluation results do not meet theactual situation and can not be applied into practice, which the risk factor equal to1000.