Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, People's Republic of China.
Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Academy of Sciences, Guangzhou, 510650, People's Republic of China.
Bull Environ Contam Toxicol. 2021 Dec;107(6):1121-1127. doi: 10.1007/s00128-021-03242-3. Epub 2021 Apr 27.
Arsenic (As) and antimony (Sb) are known carcinogens and are present as contaminants in paddy soils. However, the complicated dynamics of the mobility of these metalloids have not been well understood due to changing redox conditions in paddy soils. Herein, the kinetics of dissolved As and Sb, and functional bacteria/genes were examined in a paddy soil cultured under aerobic and anaerobic conditions. Under aerobic condition, dissolved As(V) and Sb(V) increased constantly due to sulfide oxidation by O and bound As and Sb were released. Under anaerobic condition, the reduction of As(V) and Sb(V) occurred, and the mobility of As and Sb were affected by soil redox processes. The bacteria with functional genes aioA and arrA were responsible for the direct As/Sb transformation, while Fe- and N-related bacteria had an indirect effect on the fate of As/Sb via coupling with the redox processes of Fe and N. These findings improve understanding of the mobility of As and Sb in paddy soil systems under different redox conditions.
砷（As）和锑（Sb）是已知的致癌物质，作为污染物存在于稻田土壤中。然而，由于稻田土壤中氧化还原条件的变化，这些类金属的迁移复杂动态尚未得到很好的理解。在此，在有氧和厌氧条件下培养的稻田土壤中研究了溶解态 As 和 Sb 的动力学以及功能细菌/基因。在有氧条件下，由于 O 的硫化物氧化作用，溶解态的 As(V)和 Sb(V)不断增加，结合态的 As 和 Sb 被释放出来。在厌氧条件下，As(V)和 Sb(V)发生还原，As 和 Sb 的迁移受到土壤氧化还原过程的影响。具有功能基因 aioA 和 arrA 的细菌负责直接的 As/Sb 转化，而 Fe 和 N 相关细菌通过与 Fe 和 N 的氧化还原过程偶联，对 As/Sb 的命运产生间接影响。这些发现提高了对不同氧化还原条件下稻田土壤系统中 As 和 Sb 迁移性的理解。
