Diverse coral communities in mangrove habitats suggest a novel refuge from climate change
| Autor: | James Herlan, Rebekka A. Larson, Nathan A Smiley, Caroline S. Rogers, Gregg R. Brooks, Kimberly K. Yates |
|---|---|
| Rok vydání: | 2014 |
| Předmět: |
geography
geography.geographical_feature_category Resilience of coral reefs Ecology Coral bleaching Coral lcsh:QE1-996.5 lcsh:Life Coral reef Biology biology.organism_classification lcsh:Geology lcsh:QH501-531 lcsh:QH540-549.5 lcsh:Ecology Aquaculture of coral Coral reef protection Environmental issues with coral reefs Ecology Evolution Behavior and Systematics Colpophyllia natans Earth-Surface Processes |
| Zdroj: | Biogeosciences, Vol 11, Iss 16, Pp 4321-4337 (2014) |
| ISSN: | 1726-4189 |
| DOI: | 10.5194/bg-11-4321-2014 |
| Popis: | Risk analyses indicate that more than 90% of the world's reefs will be threatened by climate change and local anthropogenic impacts by the year 2030 under "business-as-usual" climate scenarios. Increasing temperatures and solar radiation cause coral bleaching that has resulted in extensive coral mortality. Increasing carbon dioxide reduces seawater pH, slows coral growth, and may cause loss of reef structure. Management strategies include establishment of marine protected areas with environmental conditions that promote reef resiliency. However, few resilient reefs have been identified, and resiliency factors are poorly defined. Here we characterize the first natural, non-reef coral refuge from thermal stress and ocean acidification and identify resiliency factors for mangrove–coral habitats. We measured diurnal and seasonal variations in temperature, salinity, photosynthetically active radiation (PAR), and seawater chemistry; characterized substrate parameters; and examined water circulation patterns in mangrove communities where scleractinian corals are growing attached to and under mangrove prop roots in Hurricane Hole, St. John, US Virgin Islands. Additionally, we inventoried the coral species and quantified incidences of coral bleaching, mortality, and recovery for two major reef-building corals, Colpophyllia natans and Diploria labyrinthiformis, growing in mangrove-shaded and exposed (unshaded) areas. Over 30 species of scleractinian corals were growing in association with mangroves. Corals were thriving in low-light (more than 70% attenuation of incident PAR) from mangrove shading and at higher temperatures than nearby reef tract corals. A higher percentage of C. natans colonies were living shaded by mangroves, and no shaded colonies were bleached. Fewer D. labyrinthiformis colonies were shaded by mangroves, however more unshaded colonies were bleached. A combination of substrate and habitat heterogeneity, proximity of different habitat types, hydrographic conditions, and biological influences on seawater chemistry generate chemical conditions that buffer against ocean acidification. This previously undocumented refuge for corals provides evidence for adaptation of coastal organisms and ecosystem transition due to recent climate change. Identifying and protecting other natural, non-reef coral refuges is critical for sustaining corals and other reef species into the future. |
| Databáze: | OpenAIRE |
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