Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
Int J Environ Res Public Health. 2021 May 12;18(10):5128. doi: 10.3390/ijerph18105128.
The excessive cadmium (Cd) concentration in agricultural products has become a major public concern in China in recent years. In this study, two amendments, 4A molecular sieve (MS) and wollastonite (WS), were evaluated for their potential passivation in reducing Cd uptake by amaranth ( L.) in six soils with different properties. Results showed that the responses of amaranth biomass to these amendments were soil-property-dependent. The effects of MS and WS on soil available Cd were in turn dependent on soil and amendment properties. The application of WS and MS at a dose of 660 mg·kg Si produced the optimum effect on inhibiting Cd accumulation in amaranth shoots (36% and 34%, respectively) and did not affect crop yield. This was predominantly attributed to the marked increase in pH and exogenous Ca or Na, which facilitated the adsorption, precipitation, and complexation of Cd in soils. The immobilization effects of WS and MS were dependent on soil properties, where soil organic matter may have played an important role. In conclusion, MS and WS possess great potential for the remediation of Cd-contaminated acidic soils.
近年来，农产品中镉（Cd）的浓度过高已成为中国公众关注的主要问题。本研究选用 4A 分子筛（MS）和硅灰石（WS）两种改良剂，评估它们在降低六种不同性质土壤中苋菜（ L.）对 Cd 吸收的潜在钝化作用。结果表明，苋菜生物量对这些改良剂的响应取决于土壤性质。MS 和 WS 对土壤有效态 Cd 的影响依次取决于土壤和改良剂的性质。WS 和 MS 以 660 mg·kg Si 的剂量施用，对抑制苋菜地上部 Cd 积累的效果最佳（分别为 36%和 34%），且不影响作物产量。这主要归因于 pH 值和外源 Ca 或 Na 的显著增加，这有利于土壤中 Cd 的吸附、沉淀和络合。WS 和 MS 的固定化效果取决于土壤性质，其中土壤有机质可能发挥了重要作用。综上所述，MS 和 WS 具有修复酸性 Cd 污染土壤的巨大潜力。
