The role of surgeonfish (Acanthuridae) in maintaining algal turf biomass on coral reefs

Ocean acidification is a consequence of current anthropogenic climate changes.&#160;The concomitant decrease in pH and carbonate ion concentration in sea water may have severe impacts on calcifying organisms. Coral reefs are among the first ecosystems recognized vulnerable to ocean acidification. Within&#160;coral reefs, large benthic foraminifera (LBF) are major calcium carbonate producers.The aim of this study was to evaluate the effects of varying&#160;pH on&#160;survival and calcification of the&#160;symbiont-bearing LBF species Peneroplis spp.&#160;We performed culture experiments to study their&#160;resistance to ocean acidification conditions,&#160;as well as their resilience once placed back under open ocean pH (7.9).After three&#160;days, small signs of test decalcification were observed on specimens kept at pH 7.4, and severe test decalcification was observed on specimens kept at pH 6.9, with the inner organic lining clearly appearing.&#160;After 32 days under pH 7.4, similar strongly decalcified specimens were observed. All the specimens were alive&#160;at the end of the experiment. This result demonstrates the&#160;resistance of Peneroplis spp.&#160;to an acidified pH, at least on a short period of time.After being partially decalcified, some of the living specimens were placed back at pH 7.9. After one month, the majority of the specimens showed recalcification&#160;features, mostly by addition of new chambers.&#160;The trace elements concentrations of the newly formed chambers were analysed by LA-ICPMS. Interestingly, more chambers were added when food was given, which&#160;highlights the crucial role of energy source in the&#160;recalcification process. Moreover, the newly formed chambers were most of the time abnormal, and the general structure&#160;of the tests was altered, with potential impacts on reproduction and in situ survival. In conclusion, if symbiont-bearing LBF show some resistance and resilience to&#160;lowered pH&#160;conditions, they&#160;will remain&#160;strongly affected by ocean acidification.

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Coral species composition drives key ecosystem function on coral reefs

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2019.2214 ◽

2020 ◽

Vol 287 (1921) ◽

pp. 20192214 ◽

Cited By ~ 3

Author(s):

Laura E. Richardson ◽

Nicholas A. J. Graham ◽

Andrew S. Hoey

Keyword(s):

Coral Reefs ◽

Species Composition ◽

Coral Species ◽

Fish Assemblages ◽

Reef Fishes ◽

Ecosystem Functions ◽

Algal Turf ◽

Benthic Assemblages ◽

Ecosystem Recovery ◽

Visual Occlusion

Rapid and unprecedented ecological change threatens the functioning and stability of ecosystems. On coral reefs, global climate change and local stressors are reducing and reorganizing habitat-forming corals and associated species, with largely unknown implications for critical ecosystem functions such as herbivory. Herbivory mediates coral–algal competition, thereby facilitating ecosystem recovery following disturbance such as coral bleaching events or large storms. However, relationships between coral species composition, the distribution of herbivorous fishes and the delivery of their functional impact are not well understood. Here, we investigate how herbivorous fish assemblages and delivery of two distinct herbivory processes, grazing and browsing, differ among three taxonomically distinct, replicated coral habitats. While grazing on algal turf assemblages was insensitive to different coral configurations, browsing on the macroalga Laurencia cf. obtusa varied considerably among habitats, suggesting that different mechanisms may shape these processes. Variation in browsing among habitats was best predicted by the composition and structural complexity of benthic assemblages (in particular the cover and composition of corals, but not macroalgal cover), and was poorly reflected by visual estimates of browser biomass. Surprisingly, the lowest browsing rates were recorded in the most structurally complex habitat, with the greatest cover of coral (branching Porites habitat). While the mechanism for the variation in browsing is not clear, it may be related to scale-dependent effects of habitat structure on visual occlusion inhibiting foraging activity by browsing fishes, or the relative availability of alternate dietary resources. Our results suggest that maintained functionality may vary among distinct and emerging coral reef configurations due to ecological interactions between reef fishes and their environment determining habitat selection.

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Role of habitat definition on Aichi Target 11: Examples from New Caledonian coral reefs

Marine Policy ◽

10.1016/j.marpol.2020.103951 ◽

2020 ◽

Vol 116 ◽

pp. 103951 ◽

Cited By ~ 2

Author(s):

Emma Gairin ◽

Serge Andréfouët

Keyword(s):

Coral Reefs

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The role of terrestrial sediment on turbidity near Singapore's coral reefs

Continental Shelf Research ◽

10.1016/j.csr.2013.12.001 ◽

2014 ◽

Vol 76 ◽

pp. 75-88 ◽

Cited By ~ 19

Author(s):

Dirk Sebastiaan van Maren ◽

Soo Chin Liew ◽

G.M. Jahid Hasan

Keyword(s):

Coral Reefs

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Distribution and Diversity of Archaeal Ammonia Monooxygenase Genes Associated with Corals

Applied and Environmental Microbiology ◽

10.1128/aem.00461-07 ◽

2007 ◽

Vol 73 (17) ◽

pp. 5642-5647 ◽

Cited By ~ 89

Author(s):

J.Michael Beman ◽

Kathryn J. Roberts ◽

Linda Wegley ◽

Forest Rohwer ◽

Christopher A. Francis

Keyword(s):

Coral Reefs ◽

Microbial Communities ◽

Coral Species ◽

Estuarine Sediments ◽

Ammonia Monooxygenase ◽

Oceanic Water ◽

Ecological Role ◽

Bocas Del Toro ◽

Water Columns

ABSTRACT Corals are known to harbor diverse microbial communities of Bacteria and Archaea, yet the ecological role of these microorganisms remains largely unknown. Here we report putative ammonia monooxygenase subunit A (amoA) genes of archaeal origin associated with corals. Multiple DNA samples drawn from nine coral species and four different reef locations were PCR screened for archaeal and bacterial amoA genes, and archaeal amoA gene sequences were obtained from five different species of coral collected in Bocas del Toro, Panama. The 210 coral-associated archaeal amoA sequences recovered in this study were broadly distributed phylogenetically, with most only distantly related to previously reported sequences from coastal/estuarine sediments and oceanic water columns. In contrast, the bacterial amoA gene could not be amplified from any of these samples. These results offer further evidence for the widespread presence of the archaeal amoA gene in marine ecosystems, including coral reefs.

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The scientific issues surrounding remote detection of submerged coral ecosystems

Progress in Physical Geography Earth and Environment ◽

10.1177/030913339802200203 ◽

1998 ◽

Vol 22 (2) ◽

pp. 190-221 ◽

Cited By ~ 21

Author(s):

Heather Holden ◽

Ellsworth LeDrew

Keyword(s):

Remote Sensing ◽

Coral Reef ◽

Coral Reefs ◽

Large Scale ◽

Aerial Photographs ◽

Coastal Zones ◽

Global Status ◽

Coral Reef Ecosystems ◽

Remote Estimation

According to the 1993 colloquium on the ‘Global status of coral reefs', our understanding of the global role of coral reefs is inadequate. To increase our understanding, an accurate large-scale mapping and monitoring programme is necessary. Historically, coastal zones have been mapped using traditional surveying tools such as topographic maps, nautical charts, existing aerial photographs and direct observations. Although less expensive than digital imagery, exclusive use of these traditional tools may not be practical for monitoring large or remote coral reef ecosystems accurately. Researchers are attempting to develop an adequate coral reef mapping system based on digital remote sensing, but are impeded by issues such as effects of the intervening water column and spectral distinction of bottom types. The two variables discussed, which will contribute to our understanding of the global role of coral reefs, are: 1) remote sensing of submerged coral reefs in general; and 2) remote sensing of coral bleaching in particular. A summary of radiative transfer theory is presented and case studies of attempts at mapping remotely the geographic extent and health of submerged ecosystems, as well as a discussion of the remote estimation of water depth and quality. Problems in the translation and delivery of information to the end user are presented, and possible solutions suggested.

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Assessing the herbivore role of the sea-urchin Echinometra viridis: Keys to determine the structure of communities in disturbed coral reefs

Marine Environmental Research ◽

10.1016/j.marenvres.2016.08.008 ◽

2016 ◽

Vol 120 ◽

pp. 202-213 ◽

Cited By ~ 12

Author(s):

Carlos Sangil ◽

Hector M. Guzman

Keyword(s):

Coral Reefs ◽

Sea Urchin ◽

Structure Of Communities

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The Great Bacterial Reef: Communication and development in human oral bacterial biofilms

Microbiology Australia ◽

10.1071/ma05130 ◽

2005 ◽

Vol 26 (3) ◽

pp. 130

Author(s):

Paul E Kolenbrander ◽

Patricia I Diaz ◽

Nicholas S Jakubovics ◽

Alexander H Rickard ◽

Natalia I Chalmers ◽

...

Keyword(s):

Coral Reefs ◽

Great Barrier Reef ◽

Oral Hygiene ◽

Bacterial Communities ◽

Dental Plaque ◽

Oral Bacteria ◽

Bacterial Biofilms ◽

Time Interval ◽

Barrier Reef

Consider that The Great Barrier Reef is home to thousands of species of plants and animals with spatiotemporally predictable fish communities on coral reefs, and compare this with the fact that human oral bacteria develop spatiotemporally predictable dental plaque communities on enamel after each oral hygiene procedure. This reassembling of oral bacterial communities over a time interval of only a few hours offers an opportunity to investigate the role of communication in community architecture and composition.

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