The scientists studied the relationship between chlorophyll-a levels and different environmental factors in Xinghua Bay. They collected data from eight locations in spring and autumn of 2008. By using statistical analysis, they found that chlorophyll-a levels were positively linked to water temperature and ammonia nitrogen, but negatively related to pH and dissolved oxygen. However, there was no connection with chemical oxygen demand, nitrite nitrogen, nitrate nitrogen, or phosphorus. This shows that chlorophyll-a levels in Xinghua Bay are influenced by a combination of factors.