Calcification response of reef corals to seasonal upwelling in the northern Arabian Sea (Masirah Island, Oman)
<p>Tropical shallow-water reefs are the most diverse ecosystems in the ocean. Their persistence rests upon adequate calcification rates of the reef building biota, such as reef corals. Coral calcification is favoured in oligotrophic environments with high seawater saturation states of aragonit...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2022-08-01
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| Series: | Biogeosciences |
| Online Access: | https://bg.copernicus.org/articles/19/3559/2022/bg-19-3559-2022.pdf |
| _version_ | 1818010864709533696 |
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| author | P. M. Spreter M. Reuter R. Mertz-Kraus O. Taylor T. C. Brachert |
| author_facet | P. M. Spreter M. Reuter R. Mertz-Kraus O. Taylor T. C. Brachert |
| author_sort | P. M. Spreter |
| collection | DOAJ |
| description | <p>Tropical shallow-water reefs are the most diverse ecosystems in the ocean. Their persistence rests upon adequate calcification rates of the reef
building biota, such as reef corals. Coral calcification is favoured in oligotrophic environments with high seawater saturation states of aragonite
(<span class="inline-formula">Ω<sub>sw</sub></span>), which leads to an increased vulnerability to anthropogenic ocean acidification and eutrophication. Here we present
<i>Porites</i> calcification records from the northern Arabian Sea upwelling zone and investigate the coral calcification response to low
<span class="inline-formula">Ω<sub>sw</sub></span> and high nutrient concentrations due to seasonal upwelling. The calcification rate was determined from the product of skeletal
extension rate and bulk density. Skeletal <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M3" display="inline" overflow="scroll" dspmath="mathml"><mrow class="chem"><mi mathvariant="normal">Ba</mi><mo>/</mo><mi mathvariant="normal">Ca</mi></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="36pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="6ce6b2dd58dbf3d0c1decb3ec17e2c09"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-19-3559-2022-ie00001.svg" width="36pt" height="14pt" src="bg-19-3559-2022-ie00001.png"/></svg:svg></span></span> and <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M4" display="inline" overflow="scroll" dspmath="mathml"><mrow class="chem"><mi mathvariant="normal">Li</mi><mo>/</mo><mi mathvariant="normal">Mg</mi></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="32pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="9ee8ccc7e54f35210b3047764e01897b"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-19-3559-2022-ie00002.svg" width="32pt" height="14pt" src="bg-19-3559-2022-ie00002.png"/></svg:svg></span></span> proxy data were used to identify skeletal portions that calcified during upwelling and
non-upwelling seasons, respectively, and to reconstruct growth temperatures. With regard to sub-annual calcification patterns, our results
demonstrate compromised calcification rates during the upwelling season. This is due to declining extension rates, which we attribute to light
dimming caused by high primary production. Interestingly, seasonal variations in skeletal density show no relationship with temporally low
<span class="inline-formula">Ω<sub>sw</sub></span> during upwelling. This suggests relatively constant, year-round saturation states of aragonite at the site of calcification
(<span class="inline-formula">Ω<sub>cf</sub></span>) independent of external variability in <span class="inline-formula">Ω<sub>sw</sub></span>. Although upwelling does not affect seasonal density variability,
exceptionally low mean annual density implies permanent <span class="inline-formula">Ω<sub>cf</sub></span> adjustment to the lowest sub-annual <span class="inline-formula">Ω<sub>sw</sub></span> (e.g.
upwelling). In the Arabian Sea upwelling zone, the mean annual calcification rate is similar to <i>Porites</i> from non-upwelling regions because low
skeletal density is compensated by high extension growth. Variable responses of reef coral extension to nutrients, which either exacerbate or
compensate negative effects of diminished skeletal density associated with ocean acidification, may therefore be critical to the maintenance of
adequate carbonate accumulation rates in coral reefs under global change.</p> |
| first_indexed | 2024-04-14T06:00:54Z |
| format | Article |
| id | doaj.art-6a214f1829784f04bb180a8b6ec98432 |
| institution | Directory Open Access Journal |
| issn | 1726-4170 1726-4189 |
| language | English |
| last_indexed | 2024-04-14T06:00:54Z |
| publishDate | 2022-08-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Biogeosciences |
| spelling | doaj.art-6a214f1829784f04bb180a8b6ec984322022-12-22T02:08:47ZengCopernicus PublicationsBiogeosciences1726-41701726-41892022-08-01193559357310.5194/bg-19-3559-2022Calcification response of reef corals to seasonal upwelling in the northern Arabian Sea (Masirah Island, Oman)P. M. Spreter0M. Reuter1R. Mertz-Kraus2O. Taylor3T. C. Brachert4Institut für Geophysik und Geologie, Universität Leipzig, Talstraße 35, 04103 Leipzig, GermanyInstitut für Geographie und Geologie, Universität Greifswald, Friedrich-Ludwig-Jahn-Str. 17a, 17489 Greifswald, GermanyInstitut für Geowissenschaften, Johannes Gutenberg-Universität Mainz, Johann-Joachim-Becher-Weg 21, 55128 Mainz, GermanyFive Oceans Environmental Services, Villa 1756, Way 3021, Shatti Al Qurm, Muscat, Sultanate of OmanInstitut für Geophysik und Geologie, Universität Leipzig, Talstraße 35, 04103 Leipzig, Germany<p>Tropical shallow-water reefs are the most diverse ecosystems in the ocean. Their persistence rests upon adequate calcification rates of the reef building biota, such as reef corals. Coral calcification is favoured in oligotrophic environments with high seawater saturation states of aragonite (<span class="inline-formula">Ω<sub>sw</sub></span>), which leads to an increased vulnerability to anthropogenic ocean acidification and eutrophication. Here we present <i>Porites</i> calcification records from the northern Arabian Sea upwelling zone and investigate the coral calcification response to low <span class="inline-formula">Ω<sub>sw</sub></span> and high nutrient concentrations due to seasonal upwelling. The calcification rate was determined from the product of skeletal extension rate and bulk density. Skeletal <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M3" display="inline" overflow="scroll" dspmath="mathml"><mrow class="chem"><mi mathvariant="normal">Ba</mi><mo>/</mo><mi mathvariant="normal">Ca</mi></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="36pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="6ce6b2dd58dbf3d0c1decb3ec17e2c09"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-19-3559-2022-ie00001.svg" width="36pt" height="14pt" src="bg-19-3559-2022-ie00001.png"/></svg:svg></span></span> and <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M4" display="inline" overflow="scroll" dspmath="mathml"><mrow class="chem"><mi mathvariant="normal">Li</mi><mo>/</mo><mi mathvariant="normal">Mg</mi></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="32pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="9ee8ccc7e54f35210b3047764e01897b"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-19-3559-2022-ie00002.svg" width="32pt" height="14pt" src="bg-19-3559-2022-ie00002.png"/></svg:svg></span></span> proxy data were used to identify skeletal portions that calcified during upwelling and non-upwelling seasons, respectively, and to reconstruct growth temperatures. With regard to sub-annual calcification patterns, our results demonstrate compromised calcification rates during the upwelling season. This is due to declining extension rates, which we attribute to light dimming caused by high primary production. Interestingly, seasonal variations in skeletal density show no relationship with temporally low <span class="inline-formula">Ω<sub>sw</sub></span> during upwelling. This suggests relatively constant, year-round saturation states of aragonite at the site of calcification (<span class="inline-formula">Ω<sub>cf</sub></span>) independent of external variability in <span class="inline-formula">Ω<sub>sw</sub></span>. Although upwelling does not affect seasonal density variability, exceptionally low mean annual density implies permanent <span class="inline-formula">Ω<sub>cf</sub></span> adjustment to the lowest sub-annual <span class="inline-formula">Ω<sub>sw</sub></span> (e.g. upwelling). In the Arabian Sea upwelling zone, the mean annual calcification rate is similar to <i>Porites</i> from non-upwelling regions because low skeletal density is compensated by high extension growth. Variable responses of reef coral extension to nutrients, which either exacerbate or compensate negative effects of diminished skeletal density associated with ocean acidification, may therefore be critical to the maintenance of adequate carbonate accumulation rates in coral reefs under global change.</p>https://bg.copernicus.org/articles/19/3559/2022/bg-19-3559-2022.pdf |
| spellingShingle | P. M. Spreter M. Reuter R. Mertz-Kraus O. Taylor T. C. Brachert Calcification response of reef corals to seasonal upwelling in the northern Arabian Sea (Masirah Island, Oman) Biogeosciences |
| title | Calcification response of reef corals to seasonal upwelling in the northern Arabian Sea (Masirah Island, Oman) |
| title_full | Calcification response of reef corals to seasonal upwelling in the northern Arabian Sea (Masirah Island, Oman) |
| title_fullStr | Calcification response of reef corals to seasonal upwelling in the northern Arabian Sea (Masirah Island, Oman) |
| title_full_unstemmed | Calcification response of reef corals to seasonal upwelling in the northern Arabian Sea (Masirah Island, Oman) |
| title_short | Calcification response of reef corals to seasonal upwelling in the northern Arabian Sea (Masirah Island, Oman) |
| title_sort | calcification response of reef corals to seasonal upwelling in the northern arabian sea masirah island oman |
| url | https://bg.copernicus.org/articles/19/3559/2022/bg-19-3559-2022.pdf |
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