Streams in the Lake Dianchi watershed were studied to find out what's causing water pollution and how it affects the ecosystem. By looking at algae and small water creatures, the researchers found that high levels of nitrogen and phosphorus are key factors in water pollution. These pollutants were linked to changes in the aquatic life in the streams. The pollution was worst in streams flowing into the north lake, followed by those flowing into the south lake, and least in those flowing into the east lake. This information can help restore the health of the aquatic ecosystem and control water pollution in the area.