Improvement of Water Quality in the Taihu Lake From 2010 to 2023

ABSTRACT Lakes constitute critical freshwater resources increasingly threatened by industrialization and urbanization. This study analyzes spatiotemporal trends in organic pollutants, nutrients, and heavy metals in the Taihu Lake using long‐term monitoring data during 2010–2023 from 18 sites. Water quality improved significantly basin‐wide: permanganate index (COD Mn ), chemical oxygen demand (COD Cr ), and biochemical oxygen demand (BOD) fell by 34.08%, 35.20%, and 37.03%, respectively. Total nitrogen (TN), ammonia nitrogen (NH 3 ‐N), and total phosphorus (TP) decreased by 36.13%, 84.21%, and 42.86%, respectively, whereas dissolved oxygen rose by 10.9%. Heavy metals (mercury, lead, copper, arsenic, etc.) also decreased markedly, with lead concentrations dropping by 92.28%. Spatial analysis revealed pollution hotspots in northern inflow areas and cleaner conditions in southeastern outflow zones. Statistical analyses identified nutrients as the primary driver of spatial variability. These results underscore the need for geographically targeted pollution control, particularly nutrient management strategies, and furnish an empirical foundation for precision ecological restoration in the Taihu Lake and analogous aquatic systems.