Evaluation And Mechanism Of Ecological Security In Island Cities

Due to the unique sensitivity and vulnerability of the island city's ecosystem,its ecological security is gradually becoming a social focus.Ensuring the ecological security of island cities will be conducive to optimizing the living environment of islands and developing the external environment,thereby promoting high-quality economic and social development and achieving sustainable regional development of island cities.At present,China's urbanization is developing rapidly,and the strategy of strengthening the marine power is being vigorously implemented.As an important frontier base for the development of the marine economy,the island's ecological environment protection and natural resource management are facing severe challenges.Therefore,scientifically and accurately evaluating the ecological security of island cities,exploring the temporal and spatial distribution of the ecological security status of island cities on the street scale,and analyzing their mechanisms have extremely important practical significance for the construction of sustainable island cities.This study selected Zhoushan Island,Zhejiang Province as the research area,integrated RS and GIS technology,and constructed a geospatial database containing land use information of Zhoushan street scales in 2010,2013,and 2015.Based on the ecological footprint model,the streets of Zhoushan Island in the past five years were studied.Spatiotemporal changes in the ecological footprint and ecological carrying capacity,and make ecological security assessments.Then compare the expectedecological carrying capacity of the land use planning of Zhoushan Island with the status quo,and explore the key issues of ecological protection in the planning and implementation of Zhoushan.With the help of SIMCA-P 11.5 software,the partial least squares regression model is used to explore the influencing factors that influence the spatial and temporal differences of the ecological safety of the streets of Zhoushan Island,and the influencing factors of urban planning on the ecological safety of island cities are analyzed and fitted.Finally,it provides optimization countermeasures for the ecological sustainable development of island cities.The main findings are as follows:(1)Although the ecological security level of Zhoushan Island is gradually increasing,the ecosystem of each street is still in a very unsafe state.During the study period,the per capita ecological footprint of Zhoushan Island decreased from 7.355hm2 to 4.662 hm2,and the per capita ecological footprint decreased by 2.693 hm2.The per capita ecological footprint of each street is always higher than the per capita ecological carrying capacity and is in an ecological deficit.In addition,during the study period,the per capita ecological carrying capacity of all streets showed a slight growth trend,which indicates that the ecological supply of Zhoushan Island can further increase,and the expansion of construction area and standardized protection of ecological protective land are the main reasons for its growth.(2)There are obvious differences in the ecological security situation of island urban streets in different years.The ecological deficits of Changguo Street,Chengdong Street,and Lincheng Street in the densely populated area of Zhoushan are the smallest,and their ecological conditions are better than in other areas.Cities with more ecological capacity,such as Cengang in the west of Zhoushan Island The ecological footprint of the streets,Zhanmao Street in the northeast,and the relatively large number of Shuangqiao Street and Donggang Street is also high.(3)Scientific urban planning can guide the construction of ecological island cities.The 2013 version of Zhoushan's overall land use planning is expected to develop Zhoushan's per capita ecological carrying capacity to 0.371hm2 by 2020,which is three times the actual ecological carrying capacity in 2015.However,the planned expected ecological carrying capacity is still smaller than the ecological footprint,and even if it is successfully implemented according to the plan,it is still in an ecologically insecure state.In addition,regions with good levels of urbanization still maintain relative ecological safety,and the differences in the ecological safetyindex of each street are small.(4)The factors affecting the ecological construction of island cities are comprehensive and diverse.The rapid development of Zhoushan's urbanization and the rapid expansion of its urban construction area and rapid population growth are the direct factors leading to the increase in the ecological footprint of Zhoushan Island per capita.The difference in regional industrial structure,especially the spatial distribution of petrochemical heavy-consumption enterprises,is the key reason for the spatial difference in the per capita ecological footprint of each street on Zhoushan Island.In addition,the quality of urbanization development,the concentration of public service facilities,the degree of infrastructure improvement,the degree of population agglomeration,the convenience of external transportation facilities,and the consumption structure of island residents are also factors that cause the spatial and temporal differences in the ecological footprint of Zhoushan Island.(5)Propose relevant island city planning suggestions,and make relevant suggestions from the fields of urban planning,energy resource consumption,urban construction quality,regional industrial construction,and green and low-carbon life,etc.,in order to provide a theoretical basis for the construction of ecologically safe island cities.