The application of RS in wetland ecosystem health assessment: a case study of Dagu River estuary

To investigate the state and degradation degree of wetland ecosystem in Dagu River estuary, the comprehensive assessment index(CEI) method was employed. A set of assessment indicator system was established based on the Pressure-State-Response (PSR) model. In this study, wetland landscape pattern and some data was interpreted from Landsat-TM images in 2000 and 2003 for the subsequent ecosystem health assessment. Eleven indicators were elaborated and standardized by determining uniform criterion. It is found that the wetland ecosystem health in Dagu River estuary was bad both in 2000 and 2003, and human disturbance was the most important factor influencing it. During the three years, the wetland landscape has suffered serious fragmentation, and there was a downtrend both in rationality of organization and in resistibility of the wetland ecosystem. Thus, the chief measure to protect Dagu River estuary wetland should be setting a limit to human development activities.