扰动强度对菹草浸泡过程中氮磷碳释放的影响

以在北京前海采集的菹草（Potamogeton crispus）为实验材料,研究了在不同扰动强度下菹草残体浸泡过程中氮磷及高锰酸盐指数（PI）的释放特征和规律.结果表明,扰动可以加快菹草中总磷（TP）和PI的释放,在240 h的高强度扰动下,水中的氨氮（NH 4^＋-N）和总氮（TN）出现了显著（ANOVA,p〈0.0...

Influence of Disturbance Intensity on Nitrogen, Phosphorus and Permanganate Index Release of Potamogeton crispus During Soaking in Water

Influence of various disturbance intensities on nitrogen, phosphorus and permanganate index (PI) release of Potamogeton crispus were investigated during the plant soaking in water, and the plant materials were collected in an urban lake of Beijing. Results showed that more rapid release of TP and PI from Potamogeton crispus were caused by disturbance, NH⁺₄-N and TN in water were significantly increased (ANOVA, p<0.05) under the condition of high disturbance (120 r/min) for 240 h. However, PI and TP were significantly decreased (ANOVA, p<0.05) after 240 h disturbance in all treatments. When the release equilibrium of 2.13 g dry mass Potamogeton crispus in one liter of water was reached, the PI, TN, and TP released from unit mass Potamogeton crispus were 35, 5.1 and 4.1 mg·g^-1, respectively. The release ratio of TP from Potamogeton crispus was the highest, while the release ratio of PI was the lowest. The simulated experiment results showed that the highest pollution load to water released from Potamogeton crispus was the TP among the three nutrients. Phosphorus is one of the key factors which causing water eutrophication in lake, thus after submerged plants declining in lake, the field research of phosphorus release and migration from submerged plants into water is the focus of future research work.