干旱区生态环境知识资源中心

Real data from three residential urban catchments in Saudi Arabia were used to investigate the influence of duststorm characteristics on the average concentration of common nutrients, ions, and trace metals in stormwater runoff, The catchments vary in size but have almost the same physical properties. The data include samples of rainwater, stormwater, and total suspended particulate ''TSP'' matter at 17 different locations in the catchments. The TSP was evaluated by using calibrated standard high volume air samplers, and the stormwater samples were analysed for selected nutrients, ions, and trace metals. The average concentration of the majority of the investigated pollutants in the stormwater runoff of a catchment increases as the average TSP level over the catchment increases. The rate of the increase in the average concentration of ions, followed by that of trace metals, is larger than that of nutrients. These changes in the concentration of pollutants are sensitive to the temporal variation more than the spatial variation of TSP levels over catchment. Such influence on runoff quality is more noticeable in large size catchments than in small size ones.