Estuarine and coastal ecosystems are facing significant threats from compounded pressures, such as land-based pollution and mariculture activities. These ecosystems confront severe challenges, including increasing environmental burdens and declining ecological health. Traditional evaluation methods that rely on statistical data struggle to meet the requirements for refined management of estuarine and coastal water environments. Taking Qinzhou Bay as a case study, this research incorporated multi-source data (including water quality indicators retrieved from remote sensing imagery, mariculture distribution, and land use information) into an integrated ecological health assessment system that combined remotely sensed data with the Pressure–State–Response (PSR) model. This approach enables a spatially continuous and quantitative evaluation of ecological health conditions for August 2015 (flood season), December 2015 (non-flood season), May 2022 (flood season), and December 2022 (non-flood season). The results indicated significant seasonal differences in the ecological health of Qinzhou Bay, with conditions generally better during the non-flood season than the flood season. Based on a comparison between the indicative estimation for 2015 and the inversion results for 2022, the overall ecological health index in 2022 showed an increasing trend, although some nearshore and estuarine areas experienced a declining trend. This study incorporated multi-source data, including remote sensing, into the PSR model framework, thereby advancing ecological health assessment from conventional discrete station-based evaluation to spatially continuous assessment. The effectiveness of this methodological approach in identifying spatiotemporal variations in the ecological health of estuarine and coastal zones was validated, providing scientific support for the refined management of estuarine and coastal water environments and ecological restoration.
Zhang et al. (Sun,) studied this question.