Effect of silicate on arsenic fractionation in soils and its accumulation in rice plants.
Effect of silicate on arsenic fractionation in soils and its accumulation in rice plants.
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DOI：
10.1016/j.chemosphere.2016.09.061
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发表时间：
2016-12
期刊：
影响因子：
8.8
通讯作者：
Chuan Wu;Qi Zou;Sheng-guo Xue;Wei-song Pan;Xu Yue;W. Hartley;Liu Huang;Jing-yu Mo
中科院分区：
文献类型：
--
作者：
Chuan Wu;Qi Zou;Sheng-guo Xue;Wei-song Pan;Xu Yue;W. Hartley;Liu Huang;Jing-yu Mo
以2个杂交稻和2个籼型水稻为材料，研究了硅酸盐(Si)对水稻体内砷(As)积累、形态和土壤砷形态的影响。根、秸秆和籽粒生物量在不同品种间差异显著(P<0.001)，施硅显著增加根(P<0.05)和籽粒生物量(P<0.05)。添加硅酸盐降低了与结晶良好的Fe和Al水合氧化物和残留相相关的As的比例，而增加了特定吸附的As和与无定形和结晶较差的Fe和Al水合氧化物有关的As的比例。此外，结果表明，根际土壤中非专性吸附、专性吸附以及与无定形和结晶不良的水合氧化物有关的铁和铝的比例高于非根际土壤。施硅酸盐显著降低了水稻根部(P<0.005)、秸秆(P<0.05)和谷壳(P<0.001)中总砷的含量。SXRF分析揭示了硅对水稻叶片砷积累的抑制作用。与杂交种相比，不同类型的水稻对砷的运输和积累较少。杂交水稻品种XFY-9的IAS百分含量和浓度均低于杂交品种XWX-12。硅酸盐使磨粒中的IAS和DMA分别降低了21%和58%。DMA可能比无机As具有更大的从秸秆到谷物(抛光)的转运能力。这项研究为了解As在水稻中的吸收机制和减轻稻田中As污染带来的健康风险提供了潜力。
Four rice genotypes, two hybrid and two indica, were selected to investigate the effects of silicate (Si) application on arsenic (As) accumulation and speciation in rice and As fractionation in soil. There were significant differences in root, straw and grain biomass among genotypes (p < 0.05), and Si application significantly increased root (p < 0.05) and grain biomass (p < 0.001). Silicate addition reduced the proportion of As associated with well-crystallized hydrous oxides of Fe and Al and residual phases, whilst increasing the proportions of specifically-sorbed As and As associated with amorphous and poorly-crystalline Fe and Al hydrous oxides. Furthermore, the results indicated that the fraction proportions of non-specifically sorbed, specifically-sorbed, and associated with amorphous and poorly-crystalline hydrous oxides of Fe and Al in rhizosphere soils, were greater than non-rhizosphere soils. Silicate application had a significant effect decreasing total As concentrations in root (p < 0.005), straw (p < 0.05) and husk (p < 0.001) of rice plants. The effect of Si on reducing As accumulation in rice leaves was revealed by SXRF. Indica genotypes transported and accumulated less As than hybrid genotypes. Both percentage and concentration of iAs were lower in indica genotype XFY-9 than in hybrid genotype XWX-12. Silicate reduced iAs and DMA by 21% and 58% in grain (polished) respectively. DMA may have a greater translocation capacity from straw to grain (polished) than inorganic As. The study provides the potential for understanding As uptake mechanisms in rice and mitigating the health risks posed by As contamination in paddy fields.