Impacts of parent material on distributions of potentially toxic elements in soils from Pearl River Delta in South China

Abstract

Assessing the impacts of parent material on distributions of potentially toxic elements (PTEs) in soils has significant consequences in the apportionment of their sources. In this study, geochemical distributions and sources of PTEs in the soils developed in quaternary sediments and granite plutons of Pearl River Delta (PRD), South China, were investigated. The results indicate that there are systematic differences between the concentrations of oxides and PTEs in the soils developed in these two parent materials. The parent material predominantly determines the element distributions in the soils. The PTEs of the deep soils developed in quaternary sediments originated mainly from mafic, felsic, and carbonate sources materials as well as polymetallic deposits. For the deep soils developed in granite plutons, the element associations are governed mainly by their geochemical affinities and behaviors and the mineral compositions of granite plutons. Anthropogenic activities impact the features of the PTEs in the surface soils of PRD. However, superimposed regional-scale pollution was found to not hide the effect of the parent material on the distribution of PTEs in the surface soils.