Wetland ecosystem integrity and its variation in an estuary using the EBLE index

The estuary wetland in the coastal zone faces the risk of ecological integrity loss because of global environmental change and human activities. The evaluation of the estuary ecological integrity and its variation provides the basis for the environmental management of estuary wetland and coastal zone. In this study, we generalised the previous studies, extended the concept of estuary wetland ecological integrity and developed a multi-scale evaluation index system including environmental quality, biology and ecology, landscape pattern and ecosystem management (EBLE) based on dissipation theory. We applied the method to evaluate the ecological integrity in Jiulongjiang estuary in 2004 and 2009. The result indicated that the IEBLE scores in Jiulongjiang estuary were 0.64 in 2004 and 0.58 in 2009, and the IEQ, IBE, ILP and IEM scores were 0.72, 0.64, 0.57 and 0.60 in 2004 and 0.56, 0.62, 0.60 and 0.51 in 2009, respectively. The comprehensive scores had decreased in the past five years.