The researchers studied the health of the stream ecosystem in Beijing's North Canal River basin. They looked at phytoplankton, insects, and water quality at 25 sites in July 2015. By analyzing different factors, they found that only 12% of the sites were healthy or somewhat healthy, while over half were in poor or bad condition. The upstream areas were healthier than the midstream and downstream. Some specific areas like the Nansha River and Qinghe River were particularly unhealthy. Overall, the stream ecosystem in the North Canal River basin was not in good shape.