Tian Linqi, He Shangwei, Farasat Ali, Jiang Helong
Key Laboratory of Lake and Watershed Science for Water Security, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China.
Jiangsu Key Laboratory for Bioresources of Saline Soils, Jiangsu Synthetic Innovation Center for Coastal Bio-agriculture, Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection, School of Wetland, Yancheng Teachers University, Yancheng, 224007, China.
Environ Pollut. 2025 Oct 1;382:126728. doi: 10.1016/j.envpol.2025.126728. Epub 2025 Jun 25.
Increasing microplastic (MP) pollution in freshwater lakes has profound impacts on microbial communities and biogeochemical processes. Lakes are important terrestrial carbon pools and among the most active habitats for the carbon biogeochemical cycle. However, the effects of MPs on microbial community and carbon metabolism in freshwater lakes remained poorly understood. In this study, a microcosmic experiment was performed to explore the effects of four widely used plastic particles on sediment microbial community and carbon metabolic activity through high-throughput sequencing and BIOLOG analysis. The results showed that polyethylene (PE) had little effect on the bacterial network complexity, community assembly pattern, and community stability, whereas polypropylene (PP), polystyrene (PS), and polyvinyl chloride (PVC) all reduced the bacterial network complexity, improved community stability and the contribution of the stochastic processes to community assembly. Adding MPs changed the number and taxonomy of keystone species in bacterial communities. BIOLOG analysis showed that PE increased carbon metabolic activity in sediments, however, PP, PS, and PVC all had different degrees of inhibition on carbon metabolism, among which PVC had the most significant inhibition. In addition, Mantel tests and db_RDA analyses suggested a significant effect of Fe(III) and NO content on sediment carbon metabolic activity. These results provided new insight for assessing the effects of MPs on the carbon cycle in freshwater lakes and deepen the understanding about the environmental effects of MPs in the aquatic system.
淡水湖泊中微塑料（MP）污染的加剧对微生物群落和生物地球化学过程产生了深远影响。湖泊是重要的陆地碳库，也是碳生物地球化学循环最活跃的栖息地之一。然而，微塑料对淡水湖泊中微生物群落和碳代谢的影响仍知之甚少。在本研究中，通过高通量测序和BIOLOG分析进行了一项微观实验，以探究四种广泛使用的塑料颗粒对沉积物微生物群落和碳代谢活性的影响。结果表明，聚乙烯（PE）对细菌网络复杂性、群落组装模式和群落稳定性影响较小，而聚丙烯（PP）、聚苯乙烯（PS）和聚氯乙烯（PVC）均降低了细菌网络复杂性，提高了群落稳定性以及随机过程对群落组装的贡献。添加微塑料改变了细菌群落中关键物种的数量和分类。BIOLOG分析表明，PE提高了沉积物中的碳代谢活性，然而，PP、PS和PVC均对碳代谢有不同程度的抑制作用，其中PVC的抑制作用最为显著。此外，Mantel检验和db_RDA分析表明，Fe(III)和NO含量对沉积物碳代谢活性有显著影响。这些结果为评估微塑料对淡水湖泊碳循环的影响提供了新的见解，并加深了对微塑料在水生系统中环境影响的理解。
