Identifying Ecological Red Lines: A Case Study of the Coast in Liaoning Province

The global decline in estuarine and coastal ecosystems is affecting critical ecosystem services. The spatial agglomeration of population, industries and resources has led to the emergence of regionally-specific ecological problems. Therefore, identifying “ecological red lines”, based on specific natural and environmental features, could help to differentiate the economic development and ecological protection directions or potentials of different regions in future. The aim of this case study is to define the ecological red line in the coastal zone of Liaoning Province, China, by evaluating the ecological importance and environmental stress in its marine and terrestrial ecosystems. For this purpose, the ecological importance of this area was first classified into four conservation indices (species, wetland, water and coast and islands) and assigned values of 5, 3 and 1 for indications of high, moderate and minor importance. In the meantime, environmental stress was also classified into four indices (water environment, salinization, soil erosion and erosion of coasts and islands) and assigned values of 5, 3 and 1 for indications of high, moderate and low stress, respectively. Then, based on an overlay analysis and evaluation of the above results, we defined two grades of ecological red line zones. Grade I ecological red line zones contain the areas with critical and diverse ecosystem services, areas of high importance for species conservation and nature reserves, as well as ecologically-vulnerable and sensitive areas. It is important in these areas to maintain the biological diversity and to improve the quality of the ecological environment, which should be strictly protected and explicitly controlled. Grade II ecological red line zones display areas with minimum requirements for maintaining the basic needs of a livable environment and human health, moderate to minor levels of ecological importance and high to moderate levels of environmental stress. To better control and protect such ecological red lines, setting up an ecological inventory through remote sensing satellites and ground-level monitoring and appraising the effectiveness of dynamical protection are highly recommended.