Effects with Growing of Hydrilla Verticillata on the Nutrient Level of Nitrogen and Phosphorus in Interstitial Water of Eutrophic Lake

Effect with growing of submerged macrophytes on NH4+-N and PO43--P concentration in the interstitial water was studied by using sediment samples in Donghu lake.The results showed that concentration of NH4+-N from 0 to 5 centimeter in interstitial water was gradually reduced by the biomasses adding of submerged macrophytes ,and amount of nitrogen release is distinctly negative correlation with biomasses of submerged macrophytes; The PO43--P concentration in the interstitial water changing was a peak tendency by the growing of Hydrilla verticillata, it was indicated that there was also negative corresponding relationships between amount of phosphorus release and biomasses of Hydrilla verticillata. It was reflected that there were same biogeochemistry mechanism of the absorbing of nitrogen and phosphorus by submerged macrophytes. Controlling nitrogen and phosphorus nutrient level with submerged macrophytes is an effective way of governing, adjusting and inhabiting the eutrophic lake.