Wang Qian, Zhang Qionghua, Wu Yaketon, Wang Xiaochang C
Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China.
Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; International Science & Technology Cooperation Center for Urban Alternative Water Resources Development, Xi'an 710055, China.
Chemosphere. 2017 Apr;173:318-325. doi: 10.1016/j.chemosphere.2017.01.066. Epub 2017 Jan 16.
In this study, to gain an improved understanding of the fate and fractionation of particle-bound pollutants, we evaluated the physicochemical conditions and the properties of particles in rainwater, urban runoff, and rivers of Yixing, a city with a large drainage density in the Taihu Lake Basin, China. Road runoff and river samples were collected during the wet and dry seasons in 2015 and 2016. There were significant differences between the physicochemical conditions (pH, oxidation-reduction potential (ORP), and electroconductivity (EC)) of rainwater, runoff, and rivers. The lowest pH and highest ORP values of rainwater provide the optimal conditions for leaching of particle-bound pollutants such as heavy metals. The differences in the physicochemical conditions of the runoff and rivers may contribute to the redistribution of pollutants between particulate and dissolved phases after runoff is discharged into waterways. Runoff and river particles were mainly composed of silt and clay (<63 μm, 88.3%-90.7%), and runoff particles contained a higher proportion of nano-scale particles (<1 μm) but a lower proportion of submicron-scale particles (1-16 μm) than rivers. The ratio of turbidity to TSS increased with the proportion of fine particles and was associated with the accumulation of pollutants and settling ability of particles, which shows that it can be used as an index when monitoring runoff pollution.
在本研究中，为了更好地了解颗粒结合污染物的归宿和分馏情况，我们评估了中国太湖流域排水密度大的城市宜兴的雨水、城市径流和河流中的物理化学条件及颗粒特性。在2015年和2016年的雨季和旱季采集了道路径流和河流样本。雨水、径流和河流的物理化学条件（pH值、氧化还原电位（ORP）和电导率（EC））存在显著差异。雨水的最低pH值和最高ORP值为重金属等颗粒结合污染物的淋溶提供了最佳条件。径流和河流物理化学条件的差异可能导致径流排入水道后污染物在颗粒相和溶解相之间的重新分布。径流和河流颗粒主要由淤泥和粘土组成（<63μm，88.3%-90.7%），与河流相比，径流颗粒中纳米级颗粒（<1μm）的比例较高，但亚微米级颗粒（1-16μm）的比例较低。浊度与总悬浮固体的比值随细颗粒比例的增加而增加，与污染物的积累和颗粒的沉降能力相关，这表明它可作为监测径流污染时的一个指标。
