【摘要】 为了解城市中不同粒径颗粒物对于径流中污染物的影响,2006年3月在镇江城市不同功能区地表采集了沉积物样品和径流样品,分析了颗粒物的粒径分布和污染物浓度.结果表明,晴天条件下道路沉积物主要由粒径<250μm的颗粒组成;降雨初期主要为<5μm的颗粒物随径流迁移,随降雨历时的延长较大颗粒开始随径流迁移,降雨期间随地表径流迁移主要为小于150μm的颗粒物,特别是5~40μm粒径段的颗粒要特别予以关注;同时污染物浓度也由降雨初期的高浓度逐渐下降并趋于稳定.明确了径流中污染物的主要输出形态,并通过分析不同降雨历时污染物与固体悬浮物和颗粒粒径的相关性探明了径流污染物形态输出的原因,从而为城市非点源污染的管理以及控制方法的选择提供科学依据.更多还原

【Abstract】 To elucidate the relationship of particles with varying size on the pollutants in runoff, samples of road and storm-water sediment were collected from different representative land use types in Zhenjiang in 2006. Analyses were carried out to investigate the relationship between particle size distribution and concentrations of pollutants. The results showed that, in fine weather, road sediments are mainly composed of particles with size less than 250μm. At the beginning of rainfall, particles transported with surface runoff are predominantly less than 5μm, and during rainfall, become less than 150μm, with the majority in the range of 5~40μm. Meanwhile, the concentrations of pollutants decrease gradually from the beginning of rainfall until they reach a stable value. The results of the present work describe the forms of pollutants transported in runoff and present a mechanism for transport of pollutants through analyzing the relationship between pollutants or suspended solids and particle size, therefore providing a scientific basis for management of nonpoint source pollution in a city and an alternative method for controlling such pollution.更多还原