Eco-geochemical evaluation of the Leizhou Peninsula (southern China) and the prediction of heavy metal content in soils.

Abstract

The Leizhou Peninsula is an important base for tropical and subtropical cash crops in China, but still lacks systematic research on regional eco-geochemical characteristics. Here the elemental results show that risk-free soils accounted for 9168km2 and were mainly concentrated in the northern Leizhou Peninsula, while risk-controllable soils occupied 3318km2 and were mostly distributed in the southern part. The contributor of the heavy metals in soils was mainly natural rocks, while the road traffic dust and coal combustion were also responsible for the origin of anomalous elements Cd, Cr, and Ni (0.004-1.8, 0.76-590, and 0.14-372mg/kg, respectively). 90.15% of the Leizhou Peninsula plants were not obviously contaminated, yet the comparison between the data collected in 1997 and 2018 allows us to speculate that Ni in the studied soils will reach the risk screening value in 7years, followed by Cr and Cu in 39 and 92years, respectively.