The researchers studied the water quality changes in Yilong Lake from 2008 to 2018. They used two assessment methods to evaluate 13 water quality parameters and identified 6 key factors affecting water quality. The results showed that the lake's water quality improved from 2014 to 2018 due to various treatment measures and self-purification ability. Nutrients like nitrogen and phosphorus had the biggest impact on water quality. The study developed a new model, WQImin, which accurately assesses water quality changes in Yilong Lake.