Analysis and Evaluation of Heavy Metal Content in Remixing Soil by Feldspathic Sandstone and Sand in Mu Us Sandy Land, China

Abstract

In order to ensure the quality of cultivated land with the technology of remixing soil by feldspathic sandstone and sand, the concentrations of eight heavy metals were measured, and the degree of heavy metal pollution in the soil was assessed by Nemerow index and potential ecological risk index. The results showed that, compared with feldspathic, the concentrations of Cr, Ni, Cu, Zn, As, Cd and Pb in the remixing soil decreased by 12.8%, 40.7%, 44.1%, 49.3%, 49.8%, 37.6% and 14.1% respectively. The concentrations of eight heavy metals in sandstone and remixing soil were not significantly different in space, but in sand vary greatly. There was very significant positive correlation among the contents of Ni, Cu, Zn, As, Cd and Pb in the remixing soil, which indicates that the heavy metals have obvious homology. The single pollution index of heavy metals in remixing soil, feldspathic sandstone and sand were all less than one, and the comprehensive pollution index were 0.611, 0.980 and 0.395 respectively. The potential ecological risk index (RI) of heavy metals in remixing soil, feldspathic sandstone and sand were all less than 150, indicating that the soils with three textures showed low ecological risks. After three years of planting, the potential ecological risk index of heavy metals in the remixing soil increased slightly, but the single pollution index was also less than one. The research shows that the remixing soil in Mu Us Sandy Land can ensure the quality of soil environment and the safety of agricultural products.