Sulfur application modifies cadmium availability and transfer in the soil-rice system under unstable pe+pH conditions
Sulfur application modifies cadmium availability and transfer in the soil-rice system under unstable pe+pH conditions
复制标题
在不稳定的 PE pH 条件下，硫的施用改变了土壤-水稻系统中镉的有效性和转移
DOI：
10.1016/j.ecoenv.2019.109641
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发表时间：
2019
影响因子：
6.8
通讯作者：
Xiaoqin Lei
中科院分区：
文献类型：
--
作者：
Zheng Han;Meng Wang;Shibao Chen;Shanshan Li;Xiaoqin Lei
研究了在不稳定的pe + pH条件下，土壤-水稻系统中镉（Cd）的有效性和迁移对硫（S）的响应。不同的水分管理条件（淹水和好氧处理）导致土壤pe + pH值的变化。采用盆栽试验研究了硫对土壤镉有效性和水稻镉积累的影响。使用三种水制度（连续干燥、干湿交替一个循环和连续淹没）结合两种S浓度（0和300 mg/kg）。结果表明，淹水处理较好地降低了土壤pe + pH、Cd有效性和水稻组织中Cd积累量。硫诱导水稻对Cd的吸收和转运减少是由于降低了土壤pH值，促进了水稻根系中植物螯合素（PC）和谷胱甘肽（GSH）的生物合成。显微镜观察表明，淹水加硫处理对水稻根系生长有促进作用。元素色散谱（EDS）分析表明，添加硫和淹水处理促进了水稻组织中铁膜的形成和铁浓度的增加。相反，在不添加S的干燥处理中观察到根表皮部分崩解。
The objective of this study was to investigate the responses of cadmium (Cd) availability and transfer in the soil-rice system to added sulfur (S) under unstable pe + pH conditions. Different water management conditions (flooding and aerobic treatments) cause changes in the soil pe + pH. We conducted a pot experiment to investigate the influence of S supply on soil Cd availability and Cd accumulation in rice plants (Oryza sativaL.), using three water regimes (continuous dryness, alternating dry-wet for one cycle, and continuous flooding) combined with two S concentrations (0 and 300 mg/kg). The results showed that the flooding treatment was more effective in decreasing soil pe + pH, Cd availability, and Cd accumulation in rice tissues than were the aerobic treatments. S-induced reduction in Cd uptake and translocation in rice was attributed to the decreased soil pe + pH values and enhanced biosynthesis of phytochelatins (PCs) and glutathione (GSH) in rice roots. Microscopic examination showed that the flooding treatment with added soil S resulted in better rice root growth. Element dispersive spectrometer (EDS) analysis indicated that S addition and flooding treatment promoted the formation of iron plaques and increases in Fe concentration in rice tissues. Conversely, partial disintegration of the root epidermis was observed in the dry treatment without added S.