5 Conclusion
The study based on the numerical changes of 10 water quality parameters in three reservoirs in Chuzhou City from 2019 to 2021, analyzed the drivers of water quality parameters in the reservoirs over time, and comprehensively evaluated the key factors responsible for the occurrence of eutrophication in the reservoirs and the reasons for the discrepancy in the trophic status of the three reservoirs. The results show that the water quality of all three reservoirs is polluted under the impact of the natural environment and anthropogenic activities. According to the TLI method, we concluded that the water quality parameters contributing more to the occurrence of eutrophication were SD, TN, and TP. A plausible explanation for this is that when a water body is enriched with too many N and P nutrients, algae will rapidly multiply, forming water blooms and blocking light penetration, leading to eutrophication. The biased utilization of reservoir functions is the major factor contributing to the differences in the trophic status of the three reservoirs. Furthermore, eutrophication levels in the three reservoirs never showed significant signs of abatement from 2019 to 2021. Therefore, the study still needs a long time to analyze and evaluate the eutrophication of Shahe Reservoir, Huanglishu Reservoir, and Chengxi Reservoir in Chuzhou City, so as to propose a management plan for improving the water quality and reducing the nutrient index, and to ensure that the water quality of the reservoirs continues to be good.