In:
PLOS Computational Biology, Public Library of Science (PLoS), Vol. 18, No. 7 ( 2022-7-27), p. e1010291-
Kurzfassung:
Microbes play a primary role in aquatic ecosystems and biogeochemical cycles. Spatial patchiness is a critical factor underlying these activities, influencing biological productivity, nutrient cycling and dynamics across trophic levels. Incorporating spatial dynamics into microbial models is a long-standing challenge, particularly where small-scale turbulence is involved. Here, we combine a fully 3D direct numerical simulation of convective mixed layer turbulence, with an individual-based microbial model to test the key hypothesis that the coupling of gyrotactic motility and turbulence drives intense microscale patchiness. The fluid model simulates turbulent convection caused by heat loss through the fluid surface, for example during the night, during autumnal or winter cooling or during a cold-air outbreak. We find that under such conditions, turbulence-driven patchiness is depth-structured and requires high motility: Near the fluid surface, intense convective turbulence overpowers motility, homogenising motile and non-motile microbes approximately equally. At greater depth, in conditions analogous to a thermocline, highly motile microbes can be over twice as patch-concentrated as non-motile microbes, and can substantially amplify their swimming velocity by efficiently exploiting fast-moving packets of fluid. Our results substantiate the predictions of earlier studies, and demonstrate that turbulence-driven patchiness is not a ubiquitous consequence of motility but rather a delicate balance of motility and turbulent intensity.
Materialart:
Online-Ressource
ISSN:
1553-7358
DOI:
10.1371/journal.pcbi.1010291
DOI:
10.1371/journal.pcbi.1010291.g001
DOI:
10.1371/journal.pcbi.1010291.g002
DOI:
10.1371/journal.pcbi.1010291.g003
DOI:
10.1371/journal.pcbi.1010291.g004
DOI:
10.1371/journal.pcbi.1010291.g005
DOI:
10.1371/journal.pcbi.1010291.g006
DOI:
10.1371/journal.pcbi.1010291.g007
DOI:
10.1371/journal.pcbi.1010291.g008
DOI:
10.1371/journal.pcbi.1010291.t001
DOI:
10.1371/journal.pcbi.1010291.s001
DOI:
10.1371/journal.pcbi.1010291.s002
DOI:
10.1371/journal.pcbi.1010291.s003
DOI:
10.1371/journal.pcbi.1010291.s004
DOI:
10.1371/journal.pcbi.1010291.s005
DOI:
10.1371/journal.pcbi.1010291.r001
DOI:
10.1371/journal.pcbi.1010291.r002
DOI:
10.1371/journal.pcbi.1010291.r003
DOI:
10.1371/journal.pcbi.1010291.r004
DOI:
10.1371/journal.pcbi.1010291.r005
DOI:
10.1371/journal.pcbi.1010291.r006
Sprache:
Englisch
Verlag:
Public Library of Science (PLoS)
Publikationsdatum:
2022
ZDB Id:
2193340-6
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