| Popis: |
【Objective】The study was carried out to understand the distribution characteristics of heavy metals in vegetable soil in Zhanjiang City and analyze its enrichment characteristics and ecological risk status, with a view to providing basic data and scientific basis for rational vegetable planting and agricultural soil ecological improvement.【Method】38 vegetable soil samples were collected from 9 counties and districts of Zhanjiang City, and the contents of 8 heavy metals were tested. The potential ecological hazard risk index method was used to evaluate the soil ecological risks.【Result】The contents of heavy metal elements in surface soil of vegetable land in the study area shows the characteristics of Cr > Zn > Ni > Cu > Pb > As > Cd > Hg. The average content of 8 heavy metal elements exceeds the soil environmental background value of Guangdong Province. The contents of Cd and Hg are 5.53 and 5.37 times of the background value, respectively, and the exceeding standard rate of Ni is 21.1%. The average value of potential ecological risk index of vegetable surface soil in Zhanjiang City is 386.86, which belongs to strong risk. Among them, the potential ecological risks of Hg and Cd elements are high, which belong to highly strong risk and strong risk, and the other elements belong to slight risk; Xuwen County belongs to strong risk, Lianjiang City, Suixi County, Mazhang District, Chikan District and Leizhou City belong to strong risks; and Xiashan District, Potou district and Wuchuan City belong to medium risks.【Conclusion】The daily cultivation of vegetable land and the application of organic and chemical fertilizers will lead to the accumulation of heavy metal elements in soil, and the highly polluted vegetable land is basically close to residential areas, ditches, high-voltage cables and other environments conducive to the deposition of heavy metal elements. |
