Effects of Ceratophyllum demersum L. restoration on phosphorus balance at water-sediment interface

The effects of submerged macrophytes Ceratophyllum demersum L. restoration on different forms of phosphorus in overlying water, pore water and sediments were investigated under indoor condition, and the correlations between environment variables were also analyzed. The results showed that the concentrations of total phosphorous (TP), particulate phosphorus (PP), total dissolved phosphorus (TDP), soluble reactive phosphorus (SRP) in the overlying water were reduced by 73.21%, 83.78%, 70.04% and 71.94%, respectively. The effects on TDP and SRP in pore water were not significant and no effect was observed for TP and PP. However, the TP release rate from the sediment was significantly enhanced (p = 0.008), along with the increase of decomposition rates of organic phosphorous (OP) (p < 0.001) and the NH4Cl-P release rate (p < 0.001). No significant differences for BD-P, NaOH-rP, HCl-P between the experimental system and control were found in the sediment.