Diversity and Functional Potential of Microbial Communities in the Hydrocarbon Contaminated Land-sea Continuum

Download or read book Diversity and Functional Potential of Microbial Communities in the Hydrocarbon Contaminated Land-sea Continuum written by Élise Châtillon and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microbial communities in marine coastal sediment provide ecosystem services by driving essential processes including biogeochemical cycles, organic matter and pollutant degradation. In the land-sea continuum, we hypothesize that the microbial community structure and function inhabiting marine coastal ecosystems are influenced by soil runoff they receive. In order to verify the hypothesis, an experimental ecology approach was set up mimicking soil runoff within hydrocarbon (HC) contaminated land-sea continuum in microcosms. The community diversity analysis provided evidences of community coalescence (i.e. mixing of entire communities and their surrounding environments) when marine coastal sediments receive terrigenous inputs via soil runoff. The functional potential of sediment microbial communities and the removal of HC were unchanged by the terrigenous inputs. The gene variants (GVs) composition and the co-occurrence network of sediment microbial communities receiving soil runoff were modified. However, GVs encode the same function found in sediment microbial communities not influenced by soil runoff, revealing functional redundancy. Amplicon sequence variants (ASVs) and GVs were specifically associated to sediment receiving terrigenous inputs, and thus identified as indicators of community coalescence. Soil runoff was demonstrated as a plasmid reservoir, suggesting possible horizontal gene transfer mediated by plasmid during coalescence event. Our results show that community coalescence play crucial role in the organization of microbial communities in marine coastal sediment. Better understanding the coalescence mechanisms will provide useful information for the monitoring and management of coastal environment affected by human land-based activities.