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Without drastic efforts to reduce carbon emissions and mitigate globalized stressors, tropical coral reefs are in jeopardy. Strategic conservation and management requires identification of the environmental and socioeconomic factors driving the persistence of scleractinian coral assemblages—the foundation species of coral reef ecosystems. Here, we compiled coral abundance data from 2,584 Indo-Pacific reefs to evaluate the influence of 21 climate, social and environmental drivers on the ecology of reef coral assemblages. Higher abundances of framework-building corals were typically associated with: weaker thermal disturbances and longer intervals for potential recovery; slower human population growth; reduced access by human settlements and markets; and less nearby agriculture. We therefore propose a framework of three management strategies (protect, recover or transform) by considering: (1) if reefs were above or below a proposed threshold of >10% cover of the coral taxa important for structural complexity and carbonate production; and (2) reef exposure to severe thermal stress during the 2014–2017 global coral bleach- ing event. Our findings can guide urgent management efforts for coral reefs, by identifying key threats across multiple scales and strategic policy priorities that might sustain a network of functioning reefs in the Indo-Pacific to avoid ecosystem collapse.
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The response of Corbières carbonate platform to Early Cretaceous super greenhouse conditions
Shallow marine reef systems are the most diversified ecosystems of modern oceans but face a severe threat from climate change: 91% of ecosystems in the Great Barrier Reef suffer from coral bleaching. To better understand how such ecosystems cope with environmental stress, a carbonate platform from the Corbières region of southern France serves as ancient analog as it developed during the Early Aptian OAE1a, a period marked by significant climate and volcanic activity. The study sought to uncover how benthic carbonate-producing ecosystems adapted during this challenging period. The OAE1a is typically identified by distinctive shifts in carbon isotope composition (δ13C) values and increased organic matter preservation in deep marine settings. Identifying these shifts can shed light on factors favoring carbonate production. The research proposes that warm, arid climates promoted reduced continental weathering and limited transfer of siliciclastic particles and dissolved nutrients that might enhance carbonate platform resilience. We identified seven out of eight segments of the OAE1a and specific microfacies in the Corbières region. Prior to the OAE1a, carbonate production was sustained by a photozoan assemblage with rudists and [insert main biota], with no changes in fauna and flora. A significant shift occurred at the interface between the Urgonian Marl that consists of siliciclastic-rich deposits with bryozoan and crinoid, indicating platform drowning and altered carbonate production. In the aftermaths of the OAE1a, carbonate production not only rebounded but thrived in the upper Urgonian Marl and Urgonian 2 with the return of a photozoan assemblage. This research provides an understanding into the adaptability of carbonate ecosystems to environmental stress, potentially offering lessons for mitigating similar crisis in the future.
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- Award ID(s):
- 1847885
- PAR ID:
- 10520972
- Publisher / Repository:
- SEPM
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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