Qin Junhao, Li Huashou, Lin Chuxia
College of Resources and Environment, South China Agricultural University, Guangzhou, China; School of Environment and Life Science, University of Salford, Greater Manchester M5 4WT, United Kingdom.
College of Resources and Environment, South China Agricultural University, Guangzhou, China.
Ecotoxicol Environ Saf. 2016 Aug;130:4-10. doi: 10.1016/j.ecoenv.2016.03.047. Epub 2016 Apr 6.
Batch and greenhouse experiments were conducted to examine the effects of Fenton process on transformation of roxarsone in soils and its resulting impacts on the growth of and As uptake by a rice plant cultivar. The results show that addition of Fenton reagent markedly accelerated the degradation of roxarsone and produced arsenite, which was otherwise absent in the soil without added Fenton reagent. Methylation of arsenate was also enhanced by Fenton process in the earlier part of the experiment due to abundant supply of arsenate from Roxarsone degradation. Overall, addition of Fenton reagent resulted in the predominant presence of arsenate in the soils. Fenton process significantly improved the growth of rice in the maturity stage of the first crop, The concentration of methylated As species in the rice plant tissues among the different growth stages was highly variable. Addition of Fenton reagent into the soils led to reduced uptake of soil-borne As by the rice plants and this had a significant effect on reducing the accumulation of As in rice grains. The findings have implications for understanding As biogeochemistry in paddy rice field receiving rainwater-borne H2O2 and for development of mitigation strategies to reduce accumulation of As in rice grains.
进行了批次实验和温室实验，以研究芬顿法对土壤中洛克沙胂转化的影响及其对水稻品种生长和砷吸收的影响。结果表明，添加芬顿试剂显著加速了洛克沙胂的降解并产生了亚砷酸盐，而在未添加芬顿试剂的土壤中则不存在亚砷酸盐。由于洛克沙胂降解产生大量砷酸盐，在实验前期芬顿法也增强了砷酸盐的甲基化作用。总体而言，添加芬顿试剂导致土壤中主要存在砷酸盐。芬顿法显著促进了第一季作物成熟期水稻的生长。不同生长阶段水稻植株组织中甲基化砷物种的浓度变化很大。向土壤中添加芬顿试剂导致水稻植株对土壤中砷的吸收减少，这对减少水稻籽粒中砷的积累有显著影响。这些发现对于理解接受雨水携带的过氧化氢的稻田中砷的生物地球化学以及制定减少水稻籽粒中砷积累的缓解策略具有重要意义。
