Oceanic differences in coral-bleaching responses to marine heatwaves

The Science of The Total Environment, Journal Year: 2023, Volume and Issue: 871, P. 162113 - 162113

Published: Feb. 9, 2023

Anomalously high ocean temperatures have increased in frequency, intensity, and duration over the last several decades because of greenhouse gas emissions that cause global warming marine heatwaves. Reef-building corals are sensitive to such temperature anomalies commonly lead coral bleaching, mortality, changes community structure. Yet, despite these overarching effects, there geographical differences thermal regimes, evolutionary histories, past disturbances may different bleaching responses within among oceans. Here we examined overall Atlantic, Indian, Pacific Oceans, using both a spatially explicit Bayesian mixed-effects model deep-learning neural-network model. We used 40-year dataset encompassing 23,288 coral-reef surveys at 11,058 sites 88 countries, from 1980 2020. Focusing on ocean-wide assessed relationships between percentage bleached temperature-related metrics alongside suite environmental variables. found while sea-surface were consistently, strongly, related all oceans, clear most For instance, was an increase with depth Atlantic Ocean whereas opposite observed Indian Ocean, no trend could be seen Ocean. The standard deviation thermal-stress negatively but not Globally, has progressively occurred higher four although, again, three Together, patterns highlight historical circumstances oceanographic conditions play central role contemporary coral-bleaching responses.

Language: Английский

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Assessing acute thermal assays as a rapid screening tool for coral restoration

Scientific Reports, Journal Year: 2024, Volume and Issue: 14(1)

Published: Jan. 22, 2024

Abstract Escalating environmental threats to coral reefs coincides with global advancements in restoration programs. To improve long-term efficacy, practitioners must consider incorporating genotypes resilient ocean warming and disease while maintaining genetic diversity. Identifying such typically occurs under exposures that mimic natural stressors, but these experiments can be time-consuming, costly, introduce tank effects, hindering scalability for hundreds of nursery used outplanting. Here, we evaluated the efficacy acute Coral Bleaching Automated Stress System (CBASS) against on bleaching response Acropora cervicornis , dominant species Florida’s Reef. Comparing metrics, F v / m chlorophyll, host protein, observed similar responses between heat CBASS treatment 34.3 °C, which was also calculated threshold. This suggests potential as a rapid screening tool, 90% exhibiting tolerances. However, variations phenotypes arose from measurement timing experiment accumulation, cautioning generalizations solely based metrics like . These findings identify need better refine tools necessary quickly effectively screen determine their relative tolerance interventions.

Language: Английский

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Restoration cannot be scaled up globally to save reefs from loss and degradation

Nature Ecology & Evolution, Journal Year: 2025, Volume and Issue: unknown

Published: April 8, 2025

Language: Английский

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Metabolomic signatures of corals thriving across extreme reef habitats reveal strategies of heat stress tolerance

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2023, Volume and Issue: 290(1992)

Published: Feb. 8, 2023

Anthropogenic stressors continue to escalate worldwide, driving unprecedented declines in reef environmental conditions and coral health. One approach better understand how corals can function the future is examine populations that thrive within present day naturally extreme habitats. We applied untargeted metabolomics (gas chromatography–mass spectrometry (GC–MS)) contrast metabolite profiles of Pocillopora acuta colonies from hot, acidic deoxygenated mangrove environments versus those adjacent reefs. Under ambient temperatures, P. predominantly associated with endosymbionts genera Cladocopium (reef) or Durusdinium (mangrove), exhibiting elevated metabolism through energy-generating biosynthesis pathways compared populations. transient heat stress, endosymbiont associations were unchanged. Reef bleached exhibited extensive shifts symbiont metabolic (whereas host unchanged). By contrast, did not bleach solely altered, including cellular responses inter-partner signalling, antioxidant capacity energy storage. Thus resist periodically high-temperature exposure via association thermally tolerant coupled plasticity. Our findings highlight specific metabolites may be biomarkers tolerance, providing novel insight into adaptive resilience temperatures.

Language: Английский

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Ocean currents magnify upwelling and deliver nutritional subsidies to reef-building corals during El Niño heatwaves

Science Advances, Journal Year: 2023, Volume and Issue: 9(24)

Published: June 14, 2023

Marine heatwaves are triggering coral bleaching events and devastating populations globally, highlighting the need to identify processes promoting survival. Here, we show that acceleration of a major ocean current shallowing surface mixed layer enhanced localized upwelling on central Pacific reef during three strongest El Niño-associated marine past half century. These conditions mitigated regional declines in primary production bolstered local supply nutritional resources corals event. The reefs subsequently suffered limited post-bleaching mortality. Our results reveal how large-scale ocean-climate interactions affect ecosystems thousands kilometers away provide valuable framework for identifying may benefit from such biophysical linkages future events.

Language: Английский

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Quantifying the ecological consequences of climate change in coastal ecosystems

Cambridge Prisms Coastal Futures, Journal Year: 2023, Volume and Issue: 1

Published: Jan. 1, 2023

Abstract Few coastal ecosystems remain untouched by direct human activities, and none are unimpacted anthropogenic climate change. These drivers interact with exacerbate each other in complex ways, yielding a mosaic of ecological consequences that range from adaptive responses, such as geographic shifts changes phenology, to severe impacts, mass mortalities, regime loss biodiversity. Identifying the role change these phenomena requires corroborating evidence multiple lines evidence, including laboratory experiments, field observations, numerical models palaeorecords. Yet few studies can confidently quantify magnitude effect attributable solely change, because seldom acts alone ecosystems. Projections future risk further complicated scenario uncertainty – is, our lack knowledge about degree which humanity will mitigate greenhouse-gas emissions, or make ways we impact Irrespective, ocean warming would be impossible reverse before end century, sea levels likely continue rise for centuries elevated millennia. Therefore, risks projected mirror impacts already observed, severity escalating cumulative emissions. Promising avenues progress beyond qualitative assessments include collaborative modelling initiatives, model intercomparison projects, use broader systems. But reduce rapidly reducing emissions greenhouse gases, restoring damaged habitats, regulating non-climate stressors using climate-smart conservation actions, implementing inclusive coastal-zone management approaches, especially those involving nature-based solutions.

Language: Английский

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Re(de)fining degree-heating week: coral bleaching variability necessitates regional and temporal optimization of global forecast model stress metrics

Coral Reefs, Journal Year: 2024, Volume and Issue: 43(4), P. 969 - 984

Published: June 12, 2024

Abstract Tropical coral reefs are a critical ecosystem in global peril as result of anthropogenic climate change, and effective conservation efforts require reliable methods for identifying predicting bleaching events. To this end, temperature threshold-based models such the National Oceanic Atmospheric Administration’s (NOAA) degree-heating week (DHW) metric useful forecasting function heat stress accumulation. DHW does not adequately account regional variation responses, however, current definition consistently underpredicts occurrence. Using weather skill-based framework, our analysis cross-tested 1080 variations DHW-based occurrence (presence/absence) model against 22 years contemporary observations (1998–2019) order to optimize forecast skill at different levels geographic specificity. On basis relative definition, reducing 1 °C warming cutoff 0.4 °C, adjusting accumulation window 11 weeks, defining threshold 3 improved by 70%. Allowing new definitions vary across regions ocean basins further doubled skill. Our results also suggest that most change over time reef systems respond shifting climate. Since 1998, globally optimized has risen significant rate 0.19 DHW/year, matching pace warming. The trajectory each basin varies. Though work is necessary parse mechanism behind trend, dynamic nature responses demands tools be continuously refined if they inform marine efforts.

Language: Английский

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Investigating the Effects of Thermal Variability and Heatwaves on Pond Zooplankton Communities and Physiological Traits

Freshwater Biology, Journal Year: 2025, Volume and Issue: 70(1)

Published: Jan. 1, 2025

ABSTRACT To understand the impacts of climate change, we must consequences multiple and interacting timescales temperature change. While much is known about rising mean temperatures, less understood influence projected thermal variability extreme events like heatwaves on biological communities. This study investigates interaction short‐term (experimental) long‐term (historic) with zooplankton communities physiological traits. We performed a fully factorial mesocosm experiment three factors: (1) historic variation (four source ponds similar average but different daily ranges including 3.7°C, 5.9°C, 9.1°C, 10.7°C); (2) experimental (insulated non‐insulated tanks); (3) 4‐day heatwave treatment (+3.5°C) halfway through experiment. sampled community throughout assayed upper limit (CTmax) metabolic rate Daphnia dentifera Leptodiaptomus signicauda immediately before after heatwave. Zooplankton composition responded minimally to For both species, CTmax response varied by variability, increasing in individuals from low‐variability tanks decreasing high‐variability tanks. Metabolic did not vary significantly any treatments. D. L. 's seems be unaffected their history, while rely only history. rate, other hand, history or this magnitude. In spite responses at individual level, structure buffered overall Our provides new insight effects short‐ scales combined an acute changing more realistic manner. The data supports that recently thermally stable backgrounds may better equipped positively respond physiologically system could warming

Language: Английский

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Benthic algal community dynamics on Palmyra Atoll throughout a decade with two thermal anomalies

Frontiers in Marine Science, Journal Year: 2025, Volume and Issue: 12

Published: Jan. 28, 2025

Coral reef algae serve many important ecological functions, from primary production to nutrient uptake and stabilization, but our knowledge of longer-term effects thermal stress on in situ is limited. While ocean warming can facilitate proliferation potential phase shifts coral macroalgal-dominated states, algal responses may vary by species, genus, functional group, or type (e.g., calcareous vs. fleshy). We used 11 years annual monitoring data (2009-2019) that spans two El Niño-associated heatwaves examine benthic community dynamics Palmyra Atoll the central Pacific Ocean. quantified percent cover taxa via image analysis permanent photoquadrats habitats Palmyra: deeper, wave-exposed fore (10 m depth) shallower, wave-sheltered terrace (5 depth). Each habitat was characterized distinct communities: predominantly fleshy terrace. Patterns abundance fluctuated over time and/or response anomalies 2009 2015. Fleshy generally increased post-warming, which coincided with large declines calcified macroalgae, Halimeda spp. Long-term communities critical for understanding their differential improve projections ecosystem functioning context global change.

Language: Английский

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Coral reef thermal microclimates mapped from the International Space Station

Coral Reefs, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 3, 2025

Abstract Satellite sea surface temperature (SST) is critical for describing marine environments. Traditional SST data, such as those provided by the Group High Resolution Sea Surface Temperature (GHRSST) program, are valuable, but have a relatively coarse spatial resolution mapping coral reef thermal Hence, fine from orbit would be of great utility to research community and speed pathway an increased understanding how, when, where stress afflicts individual reefs. Such data support adaptive management, especially so design protected areas. Flying aboard International Space Station, NASA ECOsystem Spaceborne Thermal Radiometer Experiment on Station (ECOSTRESS) instrument may already fill this niche with 204 times finer than GHRSST. To evaluate ECOSTRESS over environments, we deployed 21 loggers three years across two sites in Red Sea. We compared retrievals both GHRSST resolution, experimental, ECOSTRESS, in-situ logger dataset. While orbital platforms correlated strongly recordings, only its 70-m pixels, could construct microclimate maps capturing dynamic fluctuations experienced our studied contend that represents significant advancement capability monitor heat reefs orbit.

Language: Английский

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