Atmospheric bulk deposition of heavy metal(loid)s in central south China: Fluxes, influencing factors and implication for paddy soils.

The depositions of heavy metal(loid)s (HMs) were measured in an urban agglomeration of China to investigate the fluxes, influencing factors, sources, and potential effects of these HMs. Our results showed that the deposition fluxes of As and Cd were higher in this area than in other regions. In the area, 59.63% of the total deposition fluxes of the Cr, Cu, Ni, Pb and Zn were observed in the wet season (March to July). Lower total fluxes of HMs were observed at the rural site. Principal component analysis (PCA) results showed that the As, Cd, Pb, and Zn might originate from the same anthropogenic sources, including traffic and industrial sources, and that the Cr, Cu, and Ni might come from natural sources. Correlation analysis and redundancy analysis (RDA) showed that rainfall, wind speed, and PMs were critical factors influencing the atmospheric bulk deposition of HMs. For the paddy soil, the input fluxes of HMs by deposition, accounted for 38.66-84.57% (except for Cr) of the total input fluxes. The prediction indicated that the accumulation of HMs in surface soil will notably increase over the next decades due to the influence of atmospheric deposition.