College of Resources and Environment, Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China.
Environ Sci Pollut Res Int. 2022 Jun;29(29):44582-44596. doi: 10.1007/s11356-022-18727-9. Epub 2022 Feb 8.
Contamination with cadmium (Cd) and lead (Pb) in rice and paddy soil threatens food safety and human health. This study determined the effects of oyster shell amendment (0, 6, and 12 g kg) on the mobility and uptake of Cd and Pb by two rice plants (ZY18, japonica and DL5, indica) in contaminated paddy soil. Oyster shell amendment significantly increased the pH of soil and pore water, and decreased the DTPA-extractable Cd concentration in soil, but not the Cd concentration in pore water. Furthermore, the DTPA-extractable Pb concentration in rhizosphere soil was not significantly influenced by oyster shell addition. Application of oyster shell reduced the Pb concentration in pore water and Pb uptake by both cultivars, but excessive application (12 g kg) resulted in Cd accumulation in tissues for ZY18. Furthermore, oyster shell addition significantly increased the dissolved organic carbon, calcium, and magnesium concentrations in soil pore water, and decreased glutathione and phytochelatin levels in roots, all of which alleviated heavy metal toxicity and improved rice growth. These results demonstrate that amendment with the appropriate amount of oyster shell, combined with rice cultivar type, could simultaneously reduce Cd and Pb accumulation in rice grown in heavy metal-contaminated soil.
贝类壳添加物（0、6 和 12 g/kg）对受污染稻田中两种水稻（ZY18，粳稻和 DL5，籼稻）吸收和迁移镉和铅的影响。贝类壳添加物显著增加了土壤和孔隙水中的 pH 值，降低了土壤中 DTPA 可提取态镉的浓度，但对孔隙水中的镉浓度没有影响。此外，贝类壳的添加对根际土壤中 DTPA 可提取态铅的浓度没有显著影响。贝类壳的应用降低了两种品种的孔隙水中的铅浓度和铅的吸收，但过量添加（12 g/kg）会导致 ZY18 组织中镉的积累。此外，贝类壳的添加显著增加了土壤孔隙水中的溶解有机碳、钙和镁浓度，并降低了根中的谷胱甘肽和植物螯合肽水平，所有这些都减轻了重金属毒性并促进了水稻生长。这些结果表明，适量添加贝类壳，并结合水稻品种，可以同时减少在重金属污染土壤中生长的水稻对镉和铅的积累。
