Remote Sensing and GIS Integration for Spatiotemporal Assessment of Environmental Deterioration and Pollution to Support Coastal Lakes Sustainability
Coastal lakes in the Mediterranean are highly sensitive ecosystems facing increasing pressure from the combined effects of anthropogenic activities and climate change. This study examined environmental changes in five Egyptian Mediterranean coastal lakes: Mariout, Edku, Burullus, Manzala, and Bardawil from 2020 to 2025, including an intermediate dataset for 2022. The assessment combined the Integrated Water Quality Index (IWQI), a Relative TDS Proxy (rTDS), and aquatic surface-cover classification derived from Sentinel-2 MSI imagery. All indicators were standardized using Z-score normalization and integrated using a weighted framework. Here, lake classifications are based solely on their connectivity to the Mediterranean Sea, regardless of other inland water sources. In Mariout (fully closed to the sea), continuous wastewater input drove a 4 km2 contraction and severe homogenization. Edku (partially open) showed a “phantom recovery” of open water (+20.84 km2) masking a 24.74% vegetation collapse and rTDS polarization. Burullus (partially open) remained relatively stable, though an 8.66 km2/yr vegetation expansion suggests a stagnation-feedback loop. Manzala (restricted-exchange) showed extreme aquaculture degradation, with fish farms expanding by 17.63 km2/yr alongside massive agricultural drains. Bardawil (open system) experienced a threefold increase in very high rTDS zones (Sen’s Slope = +8.70 km2/yr) due solely to aquaculture infrastructure restricting marine flushing. Synthesizing these findings, the apparent reduction in extreme degradation zones is a misleading indicator of recovery, reflecting progressive homogenization. The driving mechanisms vary fundamentally by hydrological connectivity: closed systems suffer pollutant retention; partially open systems face restricted inlets; restricted-exchange systems suffer internal stagnation; and open lagoons face infrastructure fragmentation. Therefore, sustainable management requires lake-specific interventions tailored to each connectivity status, focusing on nutrient reduction, hydrological restoration, and aquaculture regulation.
研究用Z-score加权整合IWQI、rTDS与水面覆盖分类，揭示“极值退化区减少”实为均质化的假性恢复，并按湖泊与海洋连通性区分四类退化机制。