Ecosystem health assessment for the Changjiang River Estuary and its adjacent sea area

Referring to the pressure-state-response(PSR) indicator structure model developed by the OECD and UNEP,the ecosystem health assessment for the Changjiang Estuary was carried out.The assess ment index system involved 22 indicators,such as annual run-off fluctuation rate,annual sediment fluctua tion rate,CODMn of sea surface,DO over standard rate,COD over standard rate,DIN over standard rate,DIP over standard rate,benthic diversity index,zooplankton copepods density ratio,and phytoplankton spe cies of algae and fecal coliforms over the standard rates,etc.Five levels of assessment criteria were sug gested.The ecosystem health status and developing trend of the Changjiang River estuary and its adjacent sea area were analyzed by using the FAME model which is established based on maximum entropy.The re sults show that the ecosystem is in the sub-healthy state.