Accumulation Characteristics of Surface Pollutants in Different Urban Land Use Types in Changzhou

In view of the problem that the non-point source pollutants had different accumulation characteristics on urban complex different underlying surfaces, the research took Changzhou central city as an example, collected 64 samples of surface pollutants on residential, industrial, traffic, commercial and cultural lands, tested the contents of SS, ammonia nitrogen and total and dissolved COD, TP, TN of surface pollutants, analyzed the accumulation characteristics of surface pollutants on different urban lands and the seasonal differences among residential and traffic lands. The results showed that the cumulative intensities of pollutants on roads were generally higher than other lands, especially SS and the total COD, with 59004.5 and 11179.7 mg/m2 respectively. The cumulative intensities of dissolved pollutants on commercial lands were highest. The cumulative intensities of pollutants on cultural, residential and industrial lands were low. The cumulative intensities in October 2014 (autumn) and March 2015 (spring) had significant seasonal differences on roads. Compared with autumn, the average cumulative intensities of SS in spring were reduced by 7.7%, while total TN and dissolved COD, TN, TP and ammonia nitrogen were increased by 3.3%, 49%, 85%, 61% and 200%. The cumulative intensities had no seasonal differences on residential lands. The average ratios of grainy to total COD, TP and TN were 86.5%, 85.1% and 71.1%, which indicated that the main pollutants were adsorbed on the particulate matters, and more urban cleaning helped reduce urban non-point source pollution. The average contents of COD and TN per unit mass of particulate matters on commercial lands were higher than that on the other lands with 532.6 mg/g and 17.5 mg/g, while that on roads were lower than that on the other lands with 212.2 mg/g (COD), 0.86 mg/g (TP) and 2.9 mg/g (TN). © 2017 Peking University.