Contents of five heavy metals in agricultural land soil in Hengshui and ecological risk assessment

Twelve sampling points were set up in farmlands in Dengzhuang Town, Hengshui. An analysis was conducted on the contents of heavy metals Cr, Mn, Pb, Cu, and Cd in the samples. The pollution of heavy metals was evaluated with the geoaccumulation index ( I geo ). Results showed that contents of Cr, Pb, Cu, and Cd at each sampling point were lower than the screening values of agricultural soil pollution risks in the Soil Environmental Quality-risk Control Standard for Soil Contamination in Agricultural Land (Trial) (GB15618-2018); Contents of heavy metals Cr, Mn, Pb and Cu were all lower than the background values of heavy metal contents in soil (BVSH) in Hebei Province, but the average content of Cd was slightly higher than BVSH. The average I geo of Cr, Mn, Pb, and Cu contents was less than 0, and the I geo at each sampling point was less than 0, based on which the soil can be regarded as pollution-free. The average I geo of Cd was very close to 0, based on which the soil can be deemed to have slight pollution.