Concentrations of total nitrogen (TN) and total phosphorus (TP) in submerged macrophytes

the corresponding sediments and water of the pollution admitted area

living and aquaculture area

and fringe area of Baiyangdian Lake were determined in April and September

2015. Along with the nutrient pollution assessment in the sediment

nutrient status and distribution of TN and TP in the waterbody of Baiyangdian Lake were investigated

the accumulation abilities of TN and TP by submerged plants from natural waters were also investigated. These findings contribute to the application of submerged aquatic plants to TN and TP removal from eutrophic water. The results showed that the content range of TN and TP in the surface water was 0.77-13.65 and 0.05-1.21 mg/L

respectively. The highest concentration of TN and TP were observed in the pollution admitted area

where the water quality ranged from Class IV to inferior Class V because of the influence of the Tanghe and Fuhe River. Concentrations of TN and TP in the living and aquaculture area and the fringe area were relatively insignificant (p > 0.05). Nitrogen and phosphorus were mainly discharged by the rivers. Moreover

the content range of TN and TP in the surface sediments was (3.16±1.86) and (0.72±0.20) g/kg

respectively. The variation range of the standard index of TN and TP

and comprehensive pollution index (PI) of the sediments in Baiyangdian Lake was 3.42-9.09

0.93-1.44

and 2.19-5.26

respectively

indicating that Baiyangdian Lake was heavily polluted

with the living and aquaculture area being more seriouly polluted than other areas. Contents of TN and TP in the sediments of the living and aquaculture area and the fringe area were relatively insignificant (p > 0.05). Among the samples of submerged macrophytes

the concentration of TN was in the order of Potamogeton crispus > Ceratophyllum demersum > Potamogeton pecinatus

while for the concentration of TP

the order was Ceratophyllum demersum > Potamogeton crispus > Potamogeton pectinatus. Significant correlations were found between the concentrations of TN and TP in the water and sediments (p < 0.05). The concentrations of TN and TP in submerged macrophytes were significantly positively related to the water but had no correlation with the sediments. In conclusion

submerged macrophytes showed strong TN and TP accumulation abilities

which are essential for developing strategies to engineer plants for phytoremediation. Accumulation of TN and TP by different submerged aquatic plants may influence the distribution of TN and TP in the waterbody

and the removal of shoots of submerged macrophytes is suggested for effective removal of TN and TP from the water system to avoid secondary pollution caused by excessive decomposition.