Ecosystem Health Assessment And Spatial Representation Of Caofeidian Coastal Zone

Coastal zone is the region with the population agglomeration,human activity frequently and economic development rapidly. The natural ecological system of coastal zone is interfered by human for a long time, coupled with the vulnerability of coastal zone itself, the impact to coastal zone is very strong. It has a close relationship between the ecosystem health of coastal zone and human survival, economic development and social sustainable development. Because of the importance of health problems, with respect to coastal ecosystem health evaluation, also get more and more people’s attention.Caofeidian is located in coastal areas, adjacent to two major economic centers of Beijing and Tianjin. In order to speed up the economic development of Caofeidian, attract foreign capital and expand industrial land, Caofeidian from 2003 officially began land reclamation project. Under huge pressure from human activities, the land use types of coastal zone undergoing rapid change, biological resources and environmental quality are also facing unprecedented test. Coastal zone ecosystem health is facing many challenges, the need for timely health evaluation coastal ecosystems to provide a theoretical basis for the search for rational development model and management strategies.In this paper, based on the research experience of domestic and foreign, from two aspects of offshore land and offshore marine to establish a set of ecosystem health evaluation method of Caofeidian coastal zone.In the health assessment of the land system in the coastal zone, using remote sensing(RS) and geographic information system(GIS) technology, five remote sensing image from 2000 to 2010 are analyzed and processed. With vigor, organization and resilience three quantitative indicators as ecosystem health evaluation model of the offshore land system of Caofeidian to scientific evaluate ecological health level. The results show that: the caofeidian coastal area with high vegetation coverage area occupied significantly increased, driving the promotion of vigor. With the speeding up of industrialization process, the construction area is increasing year by year, vegetation area shrinking, resulting in a decline in organization for land; By the normalized difference vegetation index(NDVI) change trend figure obtain that 10-year trend of average NDVI change in slope is close to zero value, indicating that land vegetation basically in a stable state, able to resist the external damage, has a certain resilience. Land comprehensive health status tends to benign development.Based on a field trip and the field investigation data in May, 2014, starting from the three factors of water environment, sedimentary environment and biotic environment to build the healthy evaluation index system of coastal marine system. Using analytic hierarchy process(AHP) to determine the weight of each evaluation index, index of EQR together with the weight are calculated for comprehensive health index(CHI) of each site, and using the fuzzy comprehensive evaluation method to get comprehensive health level of the marine. Health evaluation results show that the sedimentary environment > water environment > biological environment, comprehensive health assessment results for the sub-health. Finally, combining the inverse distance weighting(IDW) spatial interpolation method in GIS technology, according to comprehensive health index of each site to make the health level of spatial distribution map of water environment, sedimentary environment and biological environment. The health status of water environmental from shore to sea gradually change for the better spatial distribution, the health status of sedimentary environment and the biological environment is gradually decreased from the shore and the sea, but the optimal regional of health in different parts of the near shore. Combined with the health spatial distribution of the above three aspects, it is concluded that the spatial distribution regularity of comprehensive health level for caofeidian offshore marine is that on the east side of Caofeidian port to reduce gradually from the shore and the sea, opposite the west and the east side. The results for understanding the spatial difference of healthy status on different level provide the support of date.Finally, the evaluation results on the offshore land and marine are summarized in detail and the management strategies to achieve healthy development of the coastal zone is put forward. A deep understanding on the shortcomings in the course of study, the future research direction was prospected.