Characteristics of snowmelt runoff pollution and comparison with rainfall runoff pollution in Xi''an City
西安市融雪径流污染特性及其与降雨径流污染的比较

Based on the monitoring of snowmelt and rainfall runoff pollution in Xi'an city, Shaanxi Province in China, characteristics of snowmelt runoff pollution were analyzed and compared with rainfall runoff pollution, and the water quality of snowmelt runoff were evaluated. The results showed that the pollution of snowmelt runoff had first flush effect in a certain degree, with the concentrations of pollutants such as SS, COD and TN in the initial stage higher than the later stage. The water quality of undisturbed snowmelt is better, and the concentrations of most parameters were lower than those from other land uses. Quality of snowmelt runoff from different land uses differed significantly. Concentrations of most pollutants in the snowmelt runoff were lower than those in the rainfall runoff, except for TP and Zn. The snowmelt runoff concentration of TP on the school playground, rooftop and in the residential area, as well as the COD on the school road, were higher than the values of the Fifth Class of the Surface Water Quality Standard of China.