sediment Raw sequence reads

We evaluated the impact of microplastics on microbial ecosystems in wetland sediments through metagenomic sequencing.Microplastics (MPs) accumulation poses a threat to the ecosystem, but its impacts on microbial ecosystems in wetland sediments remain unclear. This study investigates the effects of different types and concentrations of MPs on microbial community composition and diversity in constructed wetland sediments. Using metagenomic sequencing, carbon metabolism, and nitrogen metabolism gene detection, we assessed the impact of polyvinyl chloride (PVC) and polylactic acid (PLA) MPs at exposure levels of 0%, 1%, and 5% in sediments. Results indicated that both types of microplastic exposure significantly (p<0.05) increased the diversity of sediment microbial communities. PVC MPs significantly enriched Acidovorax and Magnetospirillum bacteria with denitrification function, and PLA MPs significantly enriched Desulfobulbus with the organic matter oxidation function, Anaerolinea with the denitrification function, and Nitrospira with the nitrite oxidation function. Furthermore, carbon metabolism enzyme detection demonstrated that a high concentration of MPs increased the relative abundance of key enzymes of methane metabolism, EC 1.8.98.6, EC 1.8.7.3, EC 1.8.98.4, and EC 1.8.98.5. Results of nitrogen metabolism enzyme analysis found that high concentrations of MPs decrease the relative abundance of EC 1.7.2.5 and enhance EC 1.7.99. The findings of this study could help to understand the mechanisms of carbon and nitrogen cycles and microbial communities driven by MPs in sediments and provide a basis for future assessments of the environmental behavior of MPs in wetland ecosystems.