Effects of Potamogeton crispus harvesting on phosphorus components and environmental factors in Yimeng lake
In order to study the impact of P.crispus harvesting on phosphorus components in water,this study compared and analyzed the dynamic changes of phosphorus content and environmental factors in P.crispus harvesting area and P.crispus growing area of Yimeng lake during the three-year period from 2017 to 2019,and discussed the impact of harvesting on phosphorus components in water.The results showed that P.crispus harvesting could significantly improve water quality and reduce phosphorus content in water,especially in the decomposition period of P.crispus.The harvest of P.crispus could significantly reduce the content of all forms of phosphorus in water,especially the content of dissolved organic phosphorus(DOP).Sediment analysis showed that P.crispus harvesting could effectively reduce the contents of total phosphorus(TP)and organic phosphorus in sediments,and had relatively little effect on inorganic phosphorus.The monitoring results of environmental factors showed that the harvesting of P.crispus had no significant effect on pH and dissolved oxygen,but the water temperature,alkaline phosphatase activity(APA)and chlorophyll a(Chl a)were increased slightly.Correlation analysis showed that there was a weak correlation between TP and DOP in harvesting area.Harvesting treatment reduced the correlation between APA and all forms of phosphorus,DOP and Chl a.In conclusion,the selective harvesting of P.crispus in Yimeng lake at the end of April and early May each year can not only play the function of P.crispus in purifying water quality,but also avoid the secondary pollution to the water body after the decline of P.crispus.
万方数据
维普
