Abstract:
In order to study the migration pattern and enrichment characteristics of heavy metal elements in soil-crops in the black soil area of Lishu County, Jilin Province.In this study, 30 sets of rice and corn samples and their corresponding rhizosphere soil were systematically collected for analysis, and the contents of seven heavy metal elements, including Cu, Zn, Cr, Cd, Pb, As and Hg, were tested, and the enrichment characteristics and influencing factors of heavy metal elements in crops in Lishu County were investigated by using the methods such as the geo-accumulation index (Igeo), the bioconcentration factor (BCF), and the correlation analysis. The results showed that the highest heavy metal content in crops in Lishu County was Zn, the lowest was Cd and Hg, and the contents of other elements in rice and corn were slightly different. Crops have a stronger role in Zn and Cu absorption and enrichment, but a weaker ability to enrich Cd, Cr, Hg, As and Pb, and there are slight differences in the absorption and enrichment of Ni elements in different crops. Correlation analysis showed that Cu and Zn content in rice seeds showed significant positive correlation with Cr, Cu, Zn, Cd and Pb content in rhizosphere soil; Zn content in maize showed significant positive correlation with Cu, Zn and Pb content in rhizosphere soil, and Pb content in maize showed significant negative correlation with Hg content in rhizosphere soil, and the soil acidity and organic matter are also important factors influencing the content of special heavy metal elements in crops. The soil pH and organic matter are also important factors affecting the content of specialty heavy metal elements in crops. Therefore, proper adjustment of soil pH and reasonable increase of organic fertilizers can effectively control soil heavy metal pollution, which is of fundamental significance to guarantee the safety of agricultural products.