Ecological risk assessment of Yancheng Coastal Wetland

In this paper,the major ecological environment problems in the coastal wetland of Yancheng were analyzed in details.The study is based on choosing natural calamities,comprehensive pollution and Spartina alterniflora as main risk sources,red-crowned crane,other rare birds and habitat as the appraise receptor.The calculations of the ecological index with importance index of the species,bio-diversity and naturalness index,and the ecological loss index degree according to the ecological and fragile index degree of ecology were done.Then,the general system of the regional ecological risk assessment in the coastal wetland by synthesizing the ecological loss,natural calamity,comprehensive pollution and the Spartina alterniflora invading index and evaluation on the ecological risk of the coastal wetland of Yancheng were made.