Skeletal Growth Rates in Porites lutea Corals from Pulau Tinggi, Malaysia

Skeletal records of massive Porites lutea corals sampled from reefs around Malaysia have previously shown average decadal declines in growth rates associated with sea warming. However, there was a variability in growth declines between sites that warrant the need for investigations into more site-specific variations. This study analyzed decade-long (December 2004–November 2014) annual growth records (annual linear extension rate, skeletal bulk density, calcification rate) reconstructed from five massive P. lutea colonies from Pulau Tinggi, Malaysia. Significant non-linear changes in inter-annual trends of linear extension and calcification rates were found, with notable decreases that corresponded to the 2010 El Niño thermal stress episode and a pan-tropical mass coral bleaching event. Coral linear extension and calcification were observed to return to pre-2010 rates by 2012, suggesting the post-stress recovery of P. lutea corals at the study site within 2 years. Although no long-term declines in linear extension and calcification rates were detected, a linear decrease in annual skeletal bulk density by ≈9.5% over the 10-year study period was found. This suggests that although coral calcification rates are retained, the skeletal integrity of P. lutea corals may be compromised with potential implications for the strength of the overall reef carbonate framework. The correlation of coral calcification rates with sea surface temperature also demonstrated site-specific thermal threshold at 29 °C, which is comparable to the regional thermal threshold previously found for the Thai-Malay Peninsula.

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Calcification and growth rate recovery of the reef-buildingPocilloporaspecies in the northeast tropical Pacific following an ENSO disturbance

PeerJ ◽

10.7717/peerj.3191 ◽

2017 ◽

Vol 5 ◽

pp. e3191 ◽

Cited By ~ 12

Author(s):

Jose de Jesús A. Tortolero-Langarica ◽

Alma P. Rodríguez-Troncoso ◽

Amílcar L. Cupul-Magaña ◽

Juan P. Carricart-Ganivet

Keyword(s):

Growth Rates ◽

Linear Extension ◽

Growth Parameters ◽

Southern Oscillation ◽

Enso Event ◽

Tropical Pacific ◽

Extension Rate ◽

Skeletal Density ◽

Thermal Anomalies ◽

Strong Enso

Pocilloporids are one of the major reef-building corals in the eastern tropical Pacific (ETP) and also the most affected by thermal stress events, mainly those associated with El Niño/Southern Oscillation (ENSO) periods. To date, coral growth parameters have been poorly reported inPocilloporaspecies in the northeastern region of the tropical Pacific. Monthly and annual growth rates of the three most abundant morphospecies (P. cf. verrucosa,P. cf. capitata, andP. cf. damicornis) were evaluated during two annual periods at a site on the Pacific coast of Mexico. The first annual period, 2010–2011 was considered a strong ENSO/La Niña period with cool sea surface temperatures, then followed by a non-ENSO period in 2012–2013. The linear extension rate, skeletal density, and calcification rate averaged (±SD) were 2.31 ± 0.11 cm yr−1, 1.65 ± 0.18 g cm−3, 5.03 ± 0.84 g cm−2yr-1respectively, during the strong ENSO event. In contrast, the respective non-ENSO values were 3.50 ± 0.64 cm yr−1, 1.70 ± 0.18 g cm−3, and 6.02 ± 1.36 g cm−2yr−1. This corresponds to 52% and 20% faster linear extension and calcification rates, respectively, during non-ENSO period. The evidence suggests thatPocilloporabranching species responded positively with faster growth rates following thermal anomalies, which allow them to maintain coral communities in the region.

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Low Florida coral calcification rates in the Plio-Pleistocene

Biogeosciences ◽

10.5194/bg-13-4513-2016 ◽

2016 ◽

Vol 13 (15) ◽

pp. 4513-4532 ◽

Cited By ~ 1

Author(s):

Thomas C. Brachert ◽

Markus Reuter ◽

Stefan Krüger ◽

James S. Klaus ◽

Kevin Helmle ◽

...

Keyword(s):

Shallow Water ◽

Bulk Density ◽

Early Pleistocene ◽

Extension Rate ◽

Western Atlantic ◽

Skeletal Density ◽

Reef Corals ◽

Coral Calcification ◽

Diagenetic Alteration ◽

Florida Platform

Abstract. In geological outcrops and drill cores from reef frameworks, the skeletons of scleractinian corals are usually leached and more or less completely transformed into sparry calcite because the highly porous skeletons formed of metastable aragonite (CaCO3) undergo rapid diagenetic alteration. Upon alteration, ghost structures of the distinct annual growth bands often allow for reconstructions of annual extension ( =  growth) rates, but information on skeletal density needed for reconstructions of calcification rates is invariably lost. This report presents the bulk density, extension rates and calcification rates of fossil reef corals which underwent minor diagenetic alteration only. The corals derive from unlithified shallow water carbonates of the Florida platform (south-eastern USA), which formed during four interglacial sea level highstands dated approximately 3.2, 2.9, 1.8, and 1.2 Ma in the mid-Pliocene to early Pleistocene. With regard to the preservation, the coral skeletons display smooth growth surfaces with minor volumes of marine aragonite cement within intra-skeletal porosity. Within the skeletal structures, voids are commonly present along centres of calcification which lack secondary cements. Mean extension rates were 0.44 ± 0.19 cm yr−1 (range 0.16 to 0.86 cm yr−1), mean bulk density was 0.96 ± 0.36 g cm−3 (range 0.55 to 1.83 g cm−3) and calcification rates ranged from 0.18 to 0.82 g cm−2 yr−1 (mean 0.38 ± 0.16 g cm−2 yr−1), values which are 50 % of modern shallow-water reef corals. To understand the possible mechanisms behind these low calcification rates, we compared the fossil calcification rates with those of modern zooxanthellate corals (z corals) from the Western Atlantic (WA) and Indo-Pacific calibrated against sea surface temperature (SST). In the fossil data, we found a widely analogous relationship with SST in z corals from the WA, i.e. density increases and extension rate decreases with increasing SST, but over a significantly larger temperature window during the Plio-Pleistocene. With regard to the environment of coral growth, stable isotope proxy data from the fossil corals and the overall structure of the ancient shallow marine communities are consistent with a well-mixed, open marine environment similar to the present-day Florida Reef Tract, but variably affected by intermittent upwelling. Upwelling along the platform may explain low rates of reef coral calcification and inorganic cementation, but is too localised to account also for low extension rates of Pliocene z corals throughout the tropical WA region. Low aragonite saturation on a more global scale in response to rapid glacial–interglacial CO2 cyclicity is also a potential factor, but Plio-Pleistocene atmospheric pCO2 is generally believed to have been broadly similar to the present day. Heat stress related to globally high interglacial SST only episodically moderated by intermittent upwelling affecting the Florida platform seems to be another likely reason for low calcification rates. From these observations we suggest some present coral reef systems to be endangered from future ocean warming.

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Linear extension rate as express of growth rate coral Porites lutea of South Java Sea

10.1063/1.5061903 ◽

2018 ◽

Author(s):

Oktiyas Muzaky Luthfi ◽

R. M. Agung M. Rizqon Sontodipoero

Keyword(s):

Growth Rate ◽

Linear Extension ◽

Extension Rate ◽

Porites Lutea ◽

Java Sea

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Results from experiment examining effects of 4 different dyes on growth rates of scleractinian corals; from the Cohen lab at WHOI in Woods Hole, MA (OA Nutrition and Coral Calcification project)

Biological and Chemical Oceanography Data Management Office ◽

10.1575/1912/bco-dmo.489382.1 ◽

2014 ◽

Author(s):

Anne Cohen

Keyword(s):

Growth Rates ◽

Scleractinian Corals ◽

Coral Calcification

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Results from experiment examining effects of 2 different isotope spikes on growth rates of scleractinian corals; from the Cohen lab at WHOI in Woods Hole, MA (OA Nutrition and Coral Calcification project)

Biological and Chemical Oceanography Data Management Office ◽

10.1575/1912/bco-dmo.489449.1 ◽

2014 ◽

Author(s):

Anne Cohen

Keyword(s):

Growth Rates ◽

Scleractinian Corals ◽

Coral Calcification

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PRACTICAL GUIDELINES FOR ASSESSING CORAL CALCIFICATION VIA COMPUTED TOMOGRAPHY

Marine Research in Indonesia ◽

10.14203/mri.v43i2.538 ◽

2018 ◽

Vol 43 (2) ◽

pp. 95-99

Author(s):

Intan Suci Nurhati

Keyword(s):

Computed Tomography ◽

Ocean Acidification ◽

Environmental Changes ◽

Interdisciplinary Approach ◽

Standard Operating Procedure ◽

Ecological Impacts ◽

Extension Rate ◽

Skeletal Density ◽

Coral Calcification ◽

Practical Guidelines

Coral calcification as the product of extension rate and skeletal density, is projected to change under marine environmental changes of local (e.g., sedimentation, eutrophication) and global (e.g., warming, ocean acidification) scales. For the regional effort to monitor the ecological impacts of ocean acidification on coral reef ecosystems, the Intergovernmental Oceanographic Commission Sub-Commission for the Western Pacific (IOC-WESTPAC) has incorporated an interdisciplinary approach that includes monitoring of seawater carbonate parameters, coral calcification, net calcification minus bioerosion, and reef community structure. Currently, there is a need to formulate a standard operating procedure (SOP) for assessing coral calcification over the recent years via coral cores. The SOP needs to yield accurate data in a cost-effective way that can be applied by researchers in the region. High variation of coral calcification parameters between coral colonies warrants a sufficiently large number of samples thus a rapid method for analyzing coral extension rate, skeletal density, and calcification. This paper outlines practical guidelines for assessing coral calcification from the field to laboratory using the three-dimensional computed tomography (CT) method.

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Deriving SCC Initiation Times and Growth Rates from Posttest Fractrographic Analysis

CORROSION ◽

10.5006/1.3585289 ◽

1991 ◽

Vol 47 (7) ◽

pp. 528-535 ◽

Cited By ~ 10

Author(s):

T. Kobayashi ◽

D. A. Shockey ◽

R. L. Jones

Keyword(s):

Stress Corrosion ◽

Growth Rates ◽

Contaminated Water ◽

Extension Rate ◽

Clean Water ◽

Intergranular Stress Corrosion ◽

Aqueous Environments ◽

Oxygenated Water ◽

Rate Test ◽

Type 304

Abstract This exploratory effort demonstrates the feasibility of determining crack initiation times and growth rates by posttest analysis of the fracture surfaces of stress corrosion cracking (SCC) test specimens. The fracture surface topography analysis (FRASTA) technique was applied to constant extension rate test (CERT) specimens of type 304 (UNS S30400) stainless steel fractured in several aqueous environments. Initiation times and propagation rates were determined for intergranular stress corrosion cracks in specimens tested at 288°C in clean oxygenated water containing a small amount of H2SO4. Cracking appeared to begin predominantly at the specimen's surface in clean water, but in the specimen's interior in the H2SO4-contaminated water.

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