Nantong Marine Ecological Security Assessment And Pattern Construction Research

In recent years,the rough economic development model has caused certain damage to the structure and function of global ecosystems,and ecological security has gradually become a research hotspot.With the rapid development of marine economy,the development and utilization of marine resources have reached an unprecedented breadth and depth,and the ecological security problems such as marine pollution,eutrophication of surface seawater and damage to the habitat of marine organisms have become increasingly serious.Nantong is located in the core area of the Yangtze River Delta Economic Zone,the most economically developed area in China,with the Yellow Sea to the east and the Yangtze River to the south.Because of its superior location and rich resources,Nantong has a wide range of development opportunities,but the high-intensity large-scale marine development had led to a series of marine ecological safety problems,such as the lack of tidal flat area,artificialization of coastline,incomplete coastal wetland ecosystem,more serious eutrophication of surface seawater,and reduction of marine biodiversity.At the present stage,there is no domestic research practice on the construction of ecological safety pattern for sea area.In this paper,we put forward the idea of constructing marine ecological security pattern with marine ecological security as the bottom requirement and marine ecological quality as the guide for the first time,and proposed the method of constructing marine ecological security pattern based on the evaluation of marine ecological security and marine ecological quality.The research shows that the study shows that:(1)The changing trend of marine ecological safety in Nantong from 2005 to2019 is shown as follows: in 2005,Nantong Sea was in a basically safe state against the background of no large-scale development;in 2010,the high-intensity coastal areas reclamation development led to a less safe state of Nantong marine ecosystem;from 2015 to 2019,Nantong marine ecological safety showed a steady growth trend.From 2005 to 2019,the barrier factor gradually shifted from the response subsystem to the pressure subsystem,indicating that the protection and restoration measures taken for marine ecological safety problems under the premise of the general environment of coastal development gradually had an impact,but the marine ecological safety problems exposed by the rough economic development model are still significant.(2)At present,the overall ecological safety of Nantong sea area is in the state of "moderately good",with a comprehensive evaluation score between 2.36 and 3.72,and 55% of the stations belong to the medium state.From the spatial distribution,the ecological security of the sea area is mainly distributed in the outer sea area of Rudong County and Qidong City,and the ecological security of the outer sea area from Yaowang Port to Yangkou Port is relatively poor at a medium level.(3)The Nantong marine ecological security pattern of "1+3+3+7" has been constructed,in which the coastline is the marine ecological barrier,the coastal wetlands,major rivers and transportation areas constitute the marine ecological corridor,and the important marine protected areas constitute the marine ecological source and marine ecological security evaluation results as ecological zoning.Ecological protection and restoration measures such as ecological transformation of artificial seawalls,construction of ecological wetlands,enhancement of marine fishery resources,improvement of marine biodiversity and strengthening of environmental tracking and monitoring are adopted for the exposed ecological security problems.