土壤亚砷酸盐氧化菌与铁氧化物相互作用下砷的氧化与赋存机制研究

土壤中砷(As)的生物转化机制是As污染土壤重点研究内容之一。土壤中亚砷酸盐（As(Ⅲ)）氧化菌与铁（氢）氧化物相互作用下，As(Ⅲ)的氧化及其赋存状态，是这一领域尚未解决的关键科学问题之一。本项目拟以As污染土壤中筛选到的两株As(Ⅲ)氧化菌为研究对象，从不同培养和环境条件比较两种As(Ⅲ)氧化菌的As(Ⅲ)氧化能力和耐砷能力，并探讨相关调控机制；从As(Ⅲ)氧化菌和铁（氢）氧化物特点及环境条件等方面研究As(Ⅲ)氧化菌在铁（氢）氧化物上的吸附、影响因素及相关机制；构建铁（氢）氧化物-As(Ⅲ)氧化菌-砷体系，明确铁（氢）氧化物和As(Ⅲ)氧化菌相互作用下As(Ⅲ)氧化的影响因素、不同形态As在固液两相中的赋存、再分配及相关机制。本项目的研究必将对土壤中As(Ⅲ)的氧化及As在土壤中迁移转化的理论与方法起到很好的推动作用，也将为未来进行As污染土壤的生物修复及其健康风险评估提供相关依据。

Soil arsenic (As) contamination of is widespread and the mechanism of biotransformation of soil arsenic is one of the most concerned issues. Arsenite-oxidizing bacteria and iron (hydro) oxide interaction on arsenite oxidation and arsenic adsorption is one key problem still unknown. .In this project, two arsenite-oxidizing bacteria isolated from As-contaminated soil will be used and the study of this project includes: assessing oxidation ability, arsenic resistance and kinetic characteristics of the two arsenite-oxidizing bacteria; determining influence factors and mechanism of arsenite-oxidizing bacteria adsorb on iron (hydro) oxide based on the arsenite-oxidizing bacteria and iron (hydr) oxide characteristics as well as environmental conditions; illuminating the arsenite-oxidizing bacteria and iron (hydro) oxide interaction on arsenite oxidation ability, kinetic characteristics and redistribution of arsenic between solid and liquid. This research will not only play a significant role in promoting the theories and methods of arsenic oxidation, migration and transformation in soil but also provide some scientific understanding in soil arsenic bioremediation and its health risk assessment.