Review on estuary ecosystem health assessment

Estuary ecosystem is usually productive and can provide diverse ecosystem services,however,it is vulnerable to the effects of human activities. Effective assessment of estuary ecosystem health can provide the scientific basis for understanding the status and sustainability of the ecosystem. In this study,we reviewed theories on health assessment of estuary ecosystem,e. g.characteristics,conception and criterion,and summarized the index,technology and evaluation models as well as the rules for index choosing in the present applications. The technology of remote sensing( RS) and geographic information system( GIS) were additionally emphasized.Considering the existing difficulties in the health assessment of estuary ecosystem,we proposed a possible trend of development in this field. New technologies along with the concept,impact mechanism and spatial scale setting were suggested to be further strengthened in the future researches of estuary ecosystem health evaluation.