Diffuse pollution is one of the main sources that cause the deterioration of urban water quality after the point pollution is controlled effectively.Underlying surfaces such as roofs,roads,and lawns are the main types of surfaces found in city.During storm events,large amounts of pollutants deposited on the surfaces,especially roofs and roads,adding significant pollution to urban ecological environments.For this study,the quality of the three kinds of runoff was monitored in Beijing's university district,wh...