Liu Chuanping, Yu Huan-Yun, Liu Chengshuai, Li Fangbai, Xu Xianghua, Wang Qi
Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences, Guangzhou, China.
Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences, Guangzhou, China.
Environ Pollut. 2015 Apr;199:95-101. doi: 10.1016/j.envpol.2015.01.025. Epub 2015 Jan 30.
The effect of iron (Fe) redox cycling on the mobility and bioavailability of arsenic (As) in paddy soils has attracted increasing concerns, especially in Asia, where the paddy soil is characteristic of Fe with high abundance and activity. However, whether amorphous Fe oxide-bound As acts as a source or a sink of As in natural field conditions needs to be clarified further. In this study, 73 pairs of soil and rice were collected from paddy fields contaminated by As-containing acid mining drainage. The most significant correlations between the iron fractions and As fractions suggest that Fe redox cycling can directly affect As fractionation in soils, which can then indirectly affect As bioavailability. Significantly negative correlations between amorphous Fe oxide-bound As in soil and As in rice grain were found, indicating that amorphous Fe oxide-bound As acts a sink of As.
铁（Fe）的氧化还原循环对稻田土壤中砷（As）的迁移性和生物有效性的影响已引起越来越多的关注，尤其是在亚洲，那里的稻田土壤具有高丰度和活性的铁的特征。然而，在自然田间条件下，无定形铁氧化物结合态砷是作为砷的源还是汇，还需要进一步阐明。在本研究中，从受含砷酸性矿山排水污染的稻田中采集了73对土壤和水稻样本。铁组分与砷组分之间最显著的相关性表明，铁的氧化还原循环可直接影响土壤中的砷分馏，进而间接影响砷的生物有效性。研究发现，土壤中无定形铁氧化物结合态砷与水稻籽粒中的砷之间存在显著负相关，表明无定形铁氧化物结合态砷起到了砷汇的作用。
