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An Integrated Micro-Device System for Coral Growth and Monitoring
Published on: July 21, 2023
Declining coral calcification on the Great Barrier Reef
Glenn De'ath1, Janice M Lough, Katharina E Fabricius
1Australian Institute of Marine Science, Townsville, Queensland 4810, Australia. g.death@aims.gov.au
Science (New York, N.Y.)
|January 3, 2009
Summary
Coral calcification on the Great Barrier Reef has declined significantly since 1990, a trend unprecedented in 400 years. This study suggests rising ocean temperatures and reduced aragonite saturation are impacting coral growth.
Area of Science:
- Marine Biology
- Climate Science
- Geochemistry
Background:
- Reef-building corals face physiological stress due to climate change and ocean acidification.
- Massive Porites corals are key reef builders, providing valuable skeletal records.
Purpose of the Study:
- To investigate the decline in coral calcification rates across the Great Barrier Reef (GBR).
- To analyze the relationship between coral growth and environmental factors like sea surface temperature and aragonite saturation.
Main Methods:
- Examined skeletal records from 328 massive Porites coral colonies across 69 GBR reefs.
- Analyzed calcification and extension rates in relation to historical sea surface temperature and aragonite saturation data.
Main Results:
- Coral calcification in the GBR has declined by 14.2% since 1990, with linear extension decreasing by 13.3%.
- This decline is unprecedented in at least the past 400 years.
- Calcification shows a linear relationship with large-scale sea surface temperature but a nonlinear response to annual temperature anomalies.
Conclusions:
- The observed severe decline in coral calcification is likely linked to increasing temperature stress and declining aragonite saturation.
- These factors may be diminishing the capacity of GBR corals to deposit calcium carbonate, threatening reef structures.
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