Co-application of combined amendment (limestone and sepiolite) and Si fertilizer reduces rice Cd uptake and transport through Cd immobilization and Si–Cd antagonism

• Published in: Chemosphere (Oxford) 2023-03, Vol.316, p.137859, Article 137859
• Main Authors: Zeng, Peng, Liu, Jiawei, Zhou, Hang, Wei, Binyun, Gu, Jiaofeng, Liao, Ye, Liao, Bohan, Luo, Xufeng
• Format: Article
• Language: English
• Subjects: Cadmium - analysis; Calcium Carbonate - chemistry; Cd-polluted soil; Fertilizers - analysis; Foliar-sprayed Si fertilizer; Limestone and sepiolite combined amendment; Oryza - chemistry; Rice (Oryza sativa L.); Silicon - pharmacology; Soil - chemistry; Soil Pollutants - analysis; Soil-applied Si fertilizer
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2023.137859

Limestone and sepiolite combined amendment (LS) and silicon (Si) fertilizers are commonly applied for the remediation of Cd-polluted paddy soil. However, it is difficult to further decrease cadmium (Cd) accumulation in rice grains by the individual application of LS or Si fertilizer to heavily Cd-polluted paddy fields. Two seasons of continuous field experiments were conducted in heavily Cd-polluted soil to study how the co-application of LS and Si fertilizer (namely soil-applied Si and foliar-sprayed Si) influences Cd and Si bioavailability in soil and Cd uptake and transport in rice. The results indicated that LS co-applied with soil-applied Si fertilizer treatments can enhance pH, cation exchange capacity (CEC), and available Si content in soil by 0.56–1.26 units, 19.3%–57.2%, and 14.7%–58.9% (p