Content, Distribution, and Risk Assessment of Heavy Metals in Sandy Soils of the Ancient Yellow River Course

Heavy metal pollution characteristics in soils of the ancient Yellow River course are related to the ecological security of the whole Yellow River basin. In this study, the soils were collected from two functional areas (artificial forest and farmland) of the ancient Yellow River course in Yuanyang, Henan. The sand percentage was greater than 58%, and the soil was weakly alkaline with low organic matter content in the study area. The heavy metal contents in the soils were in the following order: Cr > Zn > Cu > Pb > Cd, and heavy metals might mainly originate from geological activities and pesticide residues. The metals were at a warning pollution level, and the monomial potential ecological risk factor and the risk quotient showed an ecological risk for Cd and Cr. The non-carcinogenic risk and carcinogenic risk of soil heavy metals were within the safety limits, and the non-carcinogenic risk for children was greater than that for adults. The carcinogenic risk in children and adults was within the acceptable range, but the risk was non-negligible. Taken together, these results can benefit the ecological protection and high-quality development of the Yellow River Basin and facilitate the adoption of safe regional agricultural production practices.