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An incubation experiment was performed on Potamogeton crispus (P. crispus) using sediment collected from Lake Tangxunhu in the center of China, in order to determine the effects of plant growth on Fe, Si, Cu, Zn, Mn, Mg, P, and Ca concentrations in the sediments and overlying waters. After 3 months of incubation, Ca, Mg, and Si concentrations in the water column were significantly lower, and P and Cu concentrations were significantly higher than in unplanted controls. The effect of P. crispus growth on sediment pore waters and water-extractable elements varied. Concentrations of Ca, Mg, Si, Fe, Cu, and Zn were significantly higher, and P was significantly lower, than in pore waters of the control. Waterextracted concentrations of Fe, Mg, and Si in the sediments were lower, and P was higher, than in the control. Presence of P. crispus generally enhanced concentration gradients of elements between pore waters and overlying waters but not for P. The growth of P. crispus was associated with an increase in water pH and formation of root plaques, resulting in complex effects on the sediment nutritional status.

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Sediments with and without Potamogeton crispus were simultaneously incubated outdoors to determine the effects of plant growth on the nutrients migration. After 3 months of incubation, the Fe, Mn, Si, Cu and Zn concentrations of the plant roots were significantly higher than those of the shoots (p < .05). Additionally, when P. crispus was present, the nutrient contents varied in the descending order Ca (18.54 mg/L) > Mg (4.132 mg/L) > P (8.211 μg/L) > Cu (5.45 μg/L) > Mn (0.151 μg/L) in the overlying water and in the order Ca (24.31 mg/L) > Mg (11.33 mg/L) > Mn (1349 μg/L) > P (125 μg/L) > Cu (18.91 μg/L) in the pore water. The presence of P. crispus also significantly increased the P concentration of the overlying water and the Ca, Mg and Mn concentrations of the pore water (p < .05). Furthermore, the growth of P. crispus increased the water‐extractable P level in the sediment but decreased the amounts of available Fe and Mn in the sediment (p < .05). These results indicate that the presence of P. crispus can lead to the redistribution of nutrients in sediments and in the overlying water, and this redistribution is conducive to the restoration of contaminated sediments. We suggest that more submerged macrophytes be planted in polluted water bodies to improve the water restoration effect.