Abstract Large amounts of toxic metals are discharged into rivers and lakes, but little is known about the factors that drive the adsorption and transformation of these metals in the hyporheic zone and the exchange flux across the sediment-water interface. To better understand transport and transformation of metal ions in the hyporheic zone, flume experiments and numerical simulations were performed in a streambed with periodic bedforms using zinc ions. Compared to non-adsorbing contaminant, the results show that adsorption leads to a more rapid decrease in the concentration of Zn2+ in the overlying water, and a lower final concentration is reached. The mass of adsorbed ions is several times higher than that of free ions in the bedform's water phase. Indeed, metal adsorption is in the shallow layer of the streambed. Although this prevents heavy metal groundwater contamination, the same cannot be said of shallow layer of the hyporheic zone. Knowledge of the migration and transformation of metal ions in the hyporheic zone provides insights pertinent to the restoration of polluted rivers.

中文翻译：

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下流带中锌离子的传输：实验和模拟

摘要 大量有毒金属排放到河流和湖泊中，但对这些金属在下流带的吸附和转化以及沉积物-水界面交换通量的驱动因素知之甚少。为了更好地了解下流带中金属离子的输运和转化，使用锌离子在具有周期性床型的河床中进行了水槽实验和数值模拟。与非吸附污染物相比，结果表明吸附导致上覆水中 Zn2+ 浓度的下降更快，最终浓度更低。吸附离子的质量比床型水相中游离离子的质量高几倍。事实上，金属吸附是在河床的浅层。虽然这可以防止重金属地下水污染，但对于下流带的浅层却不能这样说。关于下流带中金属离子迁移和转化的知识提供了与恢复受污染河流相关的见解。