Abundance-Occupancy Relationships Along Taxonomic Ranks Reveal a Consistency of Niche Differentiation in Marine Bacterioplankton With Distinct Lifestyles

Abstract

Abundance-occupancy relationships (AORs) are an important determinant of biotic community dynamics and habitat suitability. However, little is known about their role in complex bacterial communities, either within a phylogenetic framework or as a function of niche breadth. Based on data obtained in a field study in the St. Lawrence Estuary, we used 16S rRNA gene sequencing to examine the vertical patterns, strength, and character of AORs for particle-attached and free-living bacterial assemblages. Free-living communities were phylogenetically more diverse than particle-attached communities. The dominant taxa were consistent in terms of their presence/absence but population abundances differed in surface water vs. the cold intermediate layer. Significant, positive AORs characterized all of the surveyed communities across all taxonomic ranks of bacteria, thus demonstrating an ecologically conserved trend for both free-living and particle-attached bacteria. The strength of the AORs was low at the species level but higher at and above the genus level. These results demonstrate that an assessment of the distributions and population densities of finely resolved taxa does not necessarily improve determinations of apparent niche differences in marine bacterioplankton communities at regional scales compared with the information inferred from a broad taxonomic classification.

Distribution and diversity of anaerobic thermophiles and putative anaerobic nickel-dependent carbon monoxide-oxidizing thermophiles in mesothermal soils and sediments

“…This suggests that communities of both mesophiles and the thermophiles the emerge after heating mesothermal systems are structured by similar phenomena, primarily environmental selection. Nonetheless, occupancy patterns in this study differed in some respects from patterns in other studies of mesophiles ( Chen et al, 2020 ; Lindh et al, 2017 ; Izabel-Shen et al, 2021 ; Mateus-Barros et al, 2021 ; Yan et al, 2021 ). In particular, occupancy in regional scale studies of bacterioplankton in the Baltic Sea ( Lindh et al, 2017 ) and a set of Brazilian lakes ( Mateus-Barros et al, 2021 ) exhibited bimodal patterns with an initial decline in occupancy as site numbers increased followed by an increase in the numbers of ASVs occupying the greatest site numbers.…”

Deterministic processes drive national‐scale patterns in lake surface sediment bacteria and eukaryotic assemblage composition

“…As microbes are easily dispersed a proportion of the rare microbes could have originated in surrounding environments (e.g., terrestrial habitats) and been transported into the lake where they can no longer propagate (Pedrós‐Alió 2012). Abundance–occupancy theory suggests that taxa that have a wide niche breadth can tolerate a wider range of environmental conditions and thus have a higher occupancy rate and abundance (Izabel‐Shen et al 2021). The bacterial ASV found in the most lakes belonged to the genus Sva0081, a sulfate reducing bacteria which has been shown previously to play important roles in the sediments of lakes dominated by cyanobacteria (Fan et al 2018).…”

Regional factors as major drivers for microbial community turnover in tropical cascading reservoirs

“…Compared with particle-attached bacteria, the free-living community subset are usually smaller ( Pedrós-Alió and Brock, 1982 ) and more abundant ( Kirchman and Mitchell, 1982 ), making the free-living subcommunity more readily dispersed. Notwithstanding that particle-associated bacteria typically feature larger genome sizes than their free-living counterparts, possibly expanding their ability to adapt to variable environments and making them less sensitive to environmental change ( Smith et al, 2013 ; Izabel-Shen et al, 2021 ). However, even if regional processes were overall dominating the turnover of this community subset, variation in the free-living community was also strongly influenced by selection, especially during the dry season, and this is in accordance with our hypothesis.…”