Assessment of heavy metal concentrations in the upland soils of Gyeongnam province

Abstract

The management of heavy metals concentration in upland soil is important for a better understanding of the negative effects on the agroecosystem as well as on humans. The accumulation of heavy metals in upland soils is related to various factors, such as parent materials, topography, and soil physicochemical properties. In this study, we investigated the concentrations of 9 heavy metals (Cd, Cu, Ni, Pb, Zn, As, Cr, Cr6+, and Hg) and their relationships to environmental features of 176 upland soil samples collected from Gyeongnam Province, South Korea. Our results showed that soil pH was positively associated with the concentrations of Cd, Cu, and Zn in upland soils. Soil organic matter was also positively correlated with the concentrations of Cu, Pb, Zn, Cr6+, and Hg in upland soils. Depending on the type of crop, the concentrations of Cd, Cu, and As were highest in the soil of Chinese cabbage, while the concentrations of Pb and Zn were highest in the soil of Welsh onion. The clay contents in upland soils had a significant positive effect on the concentrations of Cu, Ni, As, and Cr. Also, the concentrations of Cd, Cu, and Zn were significantly high in fluviomarine plain, whereas those of Ni, As, and Cr were significantly high in diluvial terrace. These results showed that heavy metal concentrations in upland soils are regulated by soil physicochemical properties such as soil organic matter and clay content.

Correlation coefficient between heavy metals and soil organic matter of upland soils in Gyeongnam Province (n =176).