Four heavy metals-Cu, Zn, Pb and Cd-contained in the runoff of 3 different types of roofs in Nanjing were monitored through field sampling during 14 rainfall events. During the process, the discharge patterns of heavy metal pollution were analyzed and the concentration of heavy metals in the roof runoff and the factors influencing the runoff were explored with statistical methods. The results showed that the EMCs of the four heavy metals in the roof runoff had a normal distribution; the average event mean concentrations (EMCs) of Cu, Zn, Pb and Cd were 19.4 μg·L-1, 131.0 μg·L-1, 19.9 μg·L-1 and 0.31 μg·L-1 respectively. The heavy metal pollution in the roof runoff was mostly influenced by the number of sunny days antecedent to the rainfall event; the concentration of heavy metals in the roof runoff was influenced to a certain extent by the status of air pollution before the rainfall event; the correlation between these four heavy metals and PM10 in order of importance was Cd>Pb>Zn>Cu.
|Number of pages||7|
|Journal||Huanjing Kexue Xuebao|
|Publication status||Published - Apr 2011|
- Event mean concentration (EMCs)
- Influence factors
- Roof runoff