Heterotrophic compensation: a possible mechanism for resilience of coral reefs to global warming or a sign of prolonged stress?

Thermally induced bleaching has caused a global decline in corals and the frequency of such bleaching events will increase. Thermal bleaching severely disrupts the trophic behaviour of the coral holobiont, reducing the photosynthetically derived energy available to the coral host. In the short term...

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Main Authors: Adam D Hughes, Andréa G Grottoli
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2013-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC3837703?pdf=render
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author Adam D Hughes
Andréa G Grottoli
author_facet Adam D Hughes
Andréa G Grottoli
author_sort Adam D Hughes
collection DOAJ
description Thermally induced bleaching has caused a global decline in corals and the frequency of such bleaching events will increase. Thermal bleaching severely disrupts the trophic behaviour of the coral holobiont, reducing the photosynthetically derived energy available to the coral host. In the short term this reduction in energy transfer from endosymbiotic algae results in an energy deficit for the coral host. If the bleaching event is short-lived then the coral may survive this energy deficit by depleting its lipid reserves, or by increasing heterotrophic energy acquisition. We show for the first time that the coral animal is capable of increasing the amount of heterotrophic carbon incorporated into its tissues for almost a year following bleaching. This prolonged heterotrophic compensation could be a sign of resilience or prolonged stress. If the heterotrophic compensation is in fact an acclimatization response, then this physiological response could act as a buffer from future bleaching by providing sufficient heterotrophic energy to compensate for photoautotrophic energy losses during bleaching, and potentially minimizing the effect of subsequent elevated temperature stresses. However, if the elevated incorporation of zooplankton is a sign that the effects of bleaching continue to be stressful on the holobiont, even after 11 months of recovery, then this physiological response would indicate that complete coral recovery requires more than 11 months to achieve. If coral bleaching becomes an annual global phenomenon by mid-century, then present temporal refugia will not be sufficient to allow coral colonies to recover between bleaching events and coral reefs will become increasingly less resilient to future climate change. If, however, increasing their sequestration of zooplankton-derived nutrition into their tissues over prolonged periods of time is a compensating mechanism, the impacts of annual bleaching may be reduced. Thus, some coral species may be better equipped to face repeated bleaching stress than previously thought.
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spelling doaj.art-2cfdaa7f4c724f2a98617b910ce3ea2c2022-12-21T19:47:13ZengPublic Library of Science (PLoS)PLoS ONE1932-62032013-01-01811e8117210.1371/journal.pone.0081172Heterotrophic compensation: a possible mechanism for resilience of coral reefs to global warming or a sign of prolonged stress?Adam D HughesAndréa G GrottoliThermally induced bleaching has caused a global decline in corals and the frequency of such bleaching events will increase. Thermal bleaching severely disrupts the trophic behaviour of the coral holobiont, reducing the photosynthetically derived energy available to the coral host. In the short term this reduction in energy transfer from endosymbiotic algae results in an energy deficit for the coral host. If the bleaching event is short-lived then the coral may survive this energy deficit by depleting its lipid reserves, or by increasing heterotrophic energy acquisition. We show for the first time that the coral animal is capable of increasing the amount of heterotrophic carbon incorporated into its tissues for almost a year following bleaching. This prolonged heterotrophic compensation could be a sign of resilience or prolonged stress. If the heterotrophic compensation is in fact an acclimatization response, then this physiological response could act as a buffer from future bleaching by providing sufficient heterotrophic energy to compensate for photoautotrophic energy losses during bleaching, and potentially minimizing the effect of subsequent elevated temperature stresses. However, if the elevated incorporation of zooplankton is a sign that the effects of bleaching continue to be stressful on the holobiont, even after 11 months of recovery, then this physiological response would indicate that complete coral recovery requires more than 11 months to achieve. If coral bleaching becomes an annual global phenomenon by mid-century, then present temporal refugia will not be sufficient to allow coral colonies to recover between bleaching events and coral reefs will become increasingly less resilient to future climate change. If, however, increasing their sequestration of zooplankton-derived nutrition into their tissues over prolonged periods of time is a compensating mechanism, the impacts of annual bleaching may be reduced. Thus, some coral species may be better equipped to face repeated bleaching stress than previously thought.http://europepmc.org/articles/PMC3837703?pdf=render
spellingShingle Adam D Hughes
Andréa G Grottoli
Heterotrophic compensation: a possible mechanism for resilience of coral reefs to global warming or a sign of prolonged stress?
PLoS ONE
title Heterotrophic compensation: a possible mechanism for resilience of coral reefs to global warming or a sign of prolonged stress?
title_full Heterotrophic compensation: a possible mechanism for resilience of coral reefs to global warming or a sign of prolonged stress?
title_fullStr Heterotrophic compensation: a possible mechanism for resilience of coral reefs to global warming or a sign of prolonged stress?
title_full_unstemmed Heterotrophic compensation: a possible mechanism for resilience of coral reefs to global warming or a sign of prolonged stress?
title_short Heterotrophic compensation: a possible mechanism for resilience of coral reefs to global warming or a sign of prolonged stress?
title_sort heterotrophic compensation a possible mechanism for resilience of coral reefs to global warming or a sign of prolonged stress
url http://europepmc.org/articles/PMC3837703?pdf=render
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