In a study of a farming area in Liuxi River Valley, researchers monitored rainfall runoff to understand non-point source pollution from agriculture. They found that when it rained, pollutants like nitrogen and phosphorus in the runoff were much higher than on dry days. The pollution peaked early during rainfall, and the type of land, like residential areas or paddy fields, influenced the levels of pollutants in the water. Overall, runoff from paddy fields contributed more to nitrogen and phosphorus pollution, while runoff from residential areas had higher levels of CODCr, a measure of organic pollutants. This study reveals how different land areas can affect pollution levels in the water during rainfall events in agricultural regions.