铁硫耦合影响甲基汞在土壤-水稻系统中迁移转化的研究进展

Coupling effects of iron and sulfur on the migration and transformation of methylmercury in soil-rice system: A review

甲基汞(MeHg)具有较强的神经毒性,在稻谷中积累而产生的健康风险倍受关注。水稻(Oryza sativa L.)中甲基汞主要来源于稻田土壤,土壤中铁硫含量空间变异大,在水稻种植过程中因干湿交替作用以及根系泌氧作用而改变根际环境,使土壤甲基汞的含量及其迁移发生变化,从而影响其植物有效性。本综述系统总结了铁、硫及其相互作用对汞甲基化以及甲基汞在土壤-水稻系统中迁移转化的研究成果,并提出了甲基汞在土壤-水稻系统中迁移转化值得深入探究的相关问题,对进一步研究调控水稻中甲基汞含量以及其调控机制,降低健康风险具有重要意义。

Methylmercury （MeHg） has a strong neurotoxicity, and the health risk caused by its accumulation in rice grain has gained a lot of attention. The origin of MeHg in rice （Oryza sativa L.） comes mainly from paddy soil. The spatial variation of iron and sulfur contents in soil is large, and the interaction of iron and sulfur changes with the course of wet and dry alternation in rice planting and O2 secretion from rice roots. Changes of the content and transformation of MeHg in soil influence the MeHg availability to rice plants. This review comprehensively summarized the research achievements of iron and sulfur and their interaction effects on mercury methylation and MeHg migration and transformation in soilrice system, and put forward the potential aspects of future studies. This review will benefit further research on the regulation of MeHg formation and uptake, and on the reduction of health risks of MeHg.