Iron plaque is a Fe-containing oxide film produced by the oxidation of Fe(II) in the rice root system under the combined action of oxygen infiltration and other microorganisms. Owing to its special surface structure and physio-chemical properties, the iron plaque has a strong absorption capacity for a variety of heavy metal ions. This study aimed to first investigate the effects of Fe species on the geochemical fractionation of Tl in typical paddy soil systems affected by industrial activities, followed by pot culture experiments to probe the effects of Fe species on the uptake and translocation of Tl in rice plants. The results of field work preliminarily showed that iron at different valences affected the conversion of the Tl geochemical fraction in the soil. Oxidizable Tl exerted significant positive correlation relationships with Fe²⁺ and negative correlation relationships with Fe³⁺, while reducible Tl only displayed a positive correlation with Fe³⁺. Further analysis by pot culture experiments revealed that the contents of Fe were significantly positively correlated with Tl contents in Fe plaque (R² = 0.529). In contrast, the water-soluble Tl contents in the soil were significantly negatively correlated with the contents of Fe (R² = – 0. 90, p < 0.05). It suggests that the iron plaque promoted the absorption and fixation of Tl on the root surface of rice plants, causing Tl to accumulate in the iron plaque. Besides, the Tl content in the Fe plaque on the root surface of rice plants was greater than that in the above-ground tissues, which indicates that most Fe plaque exerts a certain degree of inhibition on Tl migration into the above-ground tissues of rice plants. All these findings indicate that Fe film is also an important carrier of Tl transfer in the soil–rice plant system, which provides new scientific support for the remediation of typical Tl-contaminated rice fields.

铁斑是水稻根系中Fe(II)在氧气渗透和其他微生物的共同作用下氧化产生的含铁氧化膜。铁菌斑由于其特殊的表面结构和理化性质，对多种重金属离子具有很强的吸附能力。本研究旨在首先研究 Fe 形态对受工业活动影响的典型水稻土系统中 Tl 地球化学分馏的影响，然后通过盆栽试验探讨 Fe 形态对水稻植物 Tl 吸收和转运的影响。野外工作结果初步表明，不同价态的铁影响土壤中Tl地球化学组分的转化。可氧化Tl与Fe呈显着正相关关系²⁺与Fe ³⁺呈负相关关系，而可还原Tl仅与Fe ³⁺呈正相关关系。盆栽实验进一步分析表明，Fe含量与Fe斑块中Tl含量呈显着正相关（R ²  = 0.529）。相反，土壤中水溶性 Tl 含量与 Fe 含量呈显着负相关 ( R ²  = – 0. 90, p < 0.05)。这表明铁斑促进了 Tl 在水稻根表面的吸收和固定，导致 Tl 在铁斑中积累。此外，水稻根表铁斑块中的Tl含量大于地上组织，说明大多数铁斑块对Tl向水稻地上组织的迁移有一定程度的抑制作用。植物。这些研究结果表明铁膜也是Tl在土壤-水稻植物系统中转移的重要载体，为典型Tl污染稻田的修复提供了新的科学支持。