Xianchuan Chen1, Xiaofei Chen2, Yanhui Zhao3, Hane Zhou3, Xiong Xiong1, Chenxi Wu4. 1. State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China. 2. Hubei Academy of Environmental Sciences, Wuhan 430072, China. 3. State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100039, China. 4. State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100039, China. Electronic address: chenxi.wu@ihb.ac.cn.
Abstract
Microplastic surfaces could be colonized by microorganisms and form biofilms in aquatic ecosystem, which can participate in the nitrogen (N) and phosphorus (P) cycles. In this work, polypropylene squares were deployed in a pond for 30 days for microplastic biofilms colonization and then were transported to indoor microcosms at an environmental relevant level to study their effects on N and P cycling. Results showed that microplastic biofilms could accelerate ammonia and nitrite oxidation as well as denitrification. Presence of microplastic biofilms accumulated P temporarily and increased alkaline phosphatase activities (APA) in the system. Later in the experiment, disintegration of matured biofilms released N and P into the water. Mass balance calculation suggested possible N input caused by biological nitrogen fixation. Our results demonstrated that microplastics associated biofilms have the ability to alter the N and P cycling processes in aquatic system. However, additional works are required to further quantify the extent of such impact.
Microplastic surfaces could be colonized by microorganisms and form biofilms in aquatic ecosystem, which can participate in the nitrogen (N) and n>an class="Chemical">phosphorus (P) cycles. In this work, polypropylene squares were deployed in a pond for 30 days for microplastic biofilms colonization and then were transported to indoor microcosms at an environmental relevant level to study their effects on N and P cycling. Results showed that microplastic biofilms could accelerate ammonia and nitrite oxidation as well as denitrification. Presence of microplastic biofilms accumulated P temporarily and increased alkaline phosphatase activities (APA) in the system. Later in the experiment, disintegration of matured biofilms released N and P into the water. Mass balance calculation suggested possible N input caused by biological nitrogen fixation. Our results demonstrated that microplastics associated biofilms have the ability to alter the N and P cycling processes in aquatic system. However, additional works are required to further quantify the extent of such impact.