We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
[Effects of PE and PLA Microplastics on Nitrogen and Phosphorus Elements in Sediments of Zhalong Wetland].
Summary
A controlled lab experiment tested how adding polyethylene (PE) and polylactic acid (PLA) microplastics at different concentrations affected nitrogen and phosphorus cycling in wetland sediments from China's Zhalong wetland. Both microplastic types significantly reduced available nitrogen and phosphorus in the sediment, with effects depending on concentration and microplastic type. These nutrient disruptions could impair the productivity of wetland ecosystems and alter water quality in connected water bodies.
Wetland sediments are the "sinks" of microplastics， nitrogen， phosphorus， and other nutrient elements in freshwater ecosystems， while microplastics have a great impact on the environment. To explore the effects of different types and contents of microplastics on nitrogen and phosphorus elements in the sediments of Zhalong wetland， an internationally important wetland， a total of seven experimental groups were set up， including CK （without microplastic addition）， PE2 （2% polyethylene microplastics）， PE5 （5% polyethylene microplastics）， PE10 （10% polyethylene microplastics）， PLA2 （2% polylactic acid microplastics）， PLA5 （5% polylactic acid microplastics）， and PLA10 （10% polylactic acid microplastics）. Culture experiments were conducted for 7， 15， and 30 days to determine total nitrogen， ammonium nitrogen， nitrate nitrogen， total phosphorus， organic phosphorus， and inorganic phosphorus in Zhalong wetland sediments. The results showed that the addition of microplastics significantly decreased the pH of Zhalong wetland sediments （P<0.05）， in which the pH of sediments decreased with the increase in PE and PLA microplastics contents， and the response to PLA microplastics was stronger. Compared with that in the blank control group， the microplastic treatment group decreased the ammonium nitrogen content and increased the nitrate nitrogen content in the sediments of Zhalong wetland， and the ammonium nitrogen content in the sediments of the PLA microplastic treatment group decreased the most， ranging from 30.1%-50.5%. The contents of ammonium nitrogen and nitrate nitrogen were negatively correlated with the content of microplastics （P<0.001） and positively correlated with the content of microplastics （P<0.05）. The addition of microplastics significantly decreased organophosphate （P<0.05） and increased inorganic phosphorus （P<0.05） in Zhalong wetland sediments. In addition， the experimental analysis showed that the addition of PE plastic mainly affected the nitration and organic phosphate mineralization by changing the pH of the sediment. The effects of PLA microplastics on nitrogen and phosphorus in Zhalong wetland sediments were mainly related to their contents. The results of this study provide basic data for the prevention and control of microplastic pollution and the protection and restoration of Zhalong wetland， as well as provide relevant references for the effects of microplastics on nitrogen and phosphorus in wetland sediments.