Index models to evaluate the potential metal pollution contribution from washoff of road-deposited sediment.
The proper evaluation of pollutant strength and loads associated with road-deposited sediment (RDS) is crucial for controlling diffuse pollution in urban areas. A new index model, which combines source and transport factors and is called the RDS index, was developed using RDS characteristics (e.g., the amount, grain size, mobility, and metal concentrations) and used in a case study in the Beijing region. The observed and weighted RDS characteristics along an urban-rural gradient, which included central urban (UCA), urban village (UVA), central suburban county (CSA), rural town (RTA), and rural village (RVA) areas, were used to calculate the RDS index for the pollutant load (RDSindex,load) and the pollutant strength (RDSindex,strength). Our results demonstrated that the RDSindex,load and RDSindex,strength values both changed significantly along the urban-rural gradient. RDSindex,strength increased along the urban-rural gradient and the RDSindex,load value along the main roads decreased in the order RVA > UCA > CSA > RTA. The method offers a new way of assessing metal pollution in RDS and provides an important scientific basis for controlling pollution caused by RDS washoff.
State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085, China.
Hongtao
H
Zhao
Zhenjiang Urban Planning and Design Institute, Zhenjiang 212132, China.
Jiang
J
Zhao
State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085, China.
Chengqing
C
Yin
State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085, China. Electronic address: xyli@rcees.ac.cn.
Xuyong
X
Li
D004784:Environmental Monitoring; D019015:Geologic Sediments; D008670:Metals / Q000737:chemistry*; D008962:Models, Theoretical; D011891:Rain; D014186:Transportation; D001335:Vehicle Emissions; D014872:Water Movements; D014874:Water Pollutants, Chemical / Q000737:chemistry*
D008670:Metals; D001335:Vehicle Emissions; D014874:Water Pollutants, Chemical
Index model; Pollution load; Pollution strength; Road-deposited sediment; Urban diffuse pollution