Ecological processes driving network bacterial associations in a floodplain fluvial system

HUBER, M. P.; MAYORA, G.; METZ, S.; SARMENTO, H.; UNREIN, F.; DEVERCELLI, M.

Congreso; International Society for Microbial Ecology - Virtual Microbial Ecology Summit; 2020

How diversity is structured has been a central goal of microbial ecology. In freshwater ecosystems, selection has been found to be the main driver shaping bacterial communities. However, it is still poor understanding how the ecological processes influence the interactions between Taxa. Cooccurrence networks are an increasingly useful tool to infer microbial interactions. In this study, we investigate the associations in bacterial metacommunities structured by different ecological processes. We carried out a spatiotemporal survey in the floodplain system of the Paraná River. We found that the networks? topology was different according to the weight of the ecological processes acting on the bacterial community assemblage. Heterogeneous selection promoted more interconnected networks increasing β-diversity. Contrarily, homogeneous selection was associated to fewer interconnected networks as decreasing β-diversity. In addition, under multiple ecological processes acting with similar strength, the network tends to be less interconnected. Beside the dominance of different ecological processes structuring the community appeared to be especially important for shaping the mutualistic and antagonistic co-occurrence patterns as well as in determining the number and identity of the most highly connected taxa in the system.