Skip to Main Content

The results above indicate that some components (such as TOC, NH4+, NO3, acetic acid, formic acid and oxalic acid) in wet deposition have dominant contributions to the mass of the components in the roof runoff. Generally, the components in the wet deposition are affected by the air quality. Spearman rank correlation analysis was used to evaluate the strength of links between the wet deposition during the rainfall events and air quality within 30 min before the rainfall events. The results indicate that TOC, NH4+, NO3, formic acid and oxalic acid in the wet deposition have moderate or strong positive correlation with PM10 in the atmospheric environment; both NO3 and NH4+ in the wet deposition have strong positive correlation with NOx in the atmospheric environment (Table 6). This is because the components may occur either as gaseous or aerosol forms in the atmospheric environment, and wet deposition rather than dry deposition is the main route through which the components in the atmospheric environment reach the rooftop (Zhang et al. 2007).

Table 6

Correlative coefficients between concentrations of components in wet deposition and atmosphere

 TOCNH4+NO3SO42–Acetic acidFormic acidOxalic acid
PM10 0.600a 0.782b 0.891b 0.782b 0.515 0.891b 0.758a 
NOx 0.527 0.794b 0.842b 0.612 0.455 0.588 0.624 
SO2 0.636a 0.770b 0.806b 0.600a 0.576a 0.661a 0.624 
 TOCNH4+NO3SO42–Acetic acidFormic acidOxalic acid
PM10 0.600a 0.782b 0.891b 0.782b 0.515 0.891b 0.758a 
NOx 0.527 0.794b 0.842b 0.612 0.455 0.588 0.624 
SO2 0.636a 0.770b 0.806b 0.600a 0.576a 0.661a 0.624 

a0.01 < p < 0.05.

bp < 0.01.

Close Modal

or Create an Account

Close Modal
Close Modal