Coral‐bleaching responses to climate change across biological scales

Global Change Biology, Journal Year: 2022, Volume and Issue: 28(14), P. 4229 - 4250

Published: April 27, 2022

Abstract The global impacts of climate change are evident in every marine ecosystem. On coral reefs, mass bleaching and mortality have emerged as ubiquitous responses to ocean warming, yet one the greatest challenges this epiphenomenon is linking information across scientific disciplines spatial temporal scales. Here we review some seminal recent coral‐bleaching discoveries from an ecological, physiological, molecular perspective. We also evaluate which data processes can improve predictive models provide a conceptual framework that integrates measurements biological Taking integrative approach scales, using for example hierarchical estimate major coral‐reef processes, will not only rapidly advance science but necessary guide decision‐making conservation efforts. To conserve encourage implementing mesoscale sanctuaries (thousands km 2 ) transcend national boundaries. Such networks protected reefs reef connectivity, through larval dispersal transverse thermal environments, genotypic repositories may become essential units selection environmentally diverse locations. Together, multinational be best chance corals persist change, while humanity struggles reduce emissions greenhouse gases net zero.

Language: Английский

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Triggers, cascades, and endpoints: connecting the dots of coral bleaching mechanisms

Biological reviews/Biological reviews of the Cambridge Philosophical Society, Journal Year: 2024, Volume and Issue: 99(3), P. 715 - 752

Published: Jan. 12, 2024

ABSTRACT The intracellular coral–dinoflagellate symbiosis is the engine that underpins success of coral reefs, one most diverse ecosystems on planet. However, breakdown and loss microalgal symbiont (i.e. bleaching) due to environmental changes are resulting in rapid degradation reefs globally. There an urgent need understand cellular physiology bleaching at mechanistic level help develop solutions mitigate reef crisis. Here, unprecedented scope, we present novel models integrate putative mechanisms within a common framework according triggers (initiators bleaching, e.g. heat, cold, light stress, hypoxia, hyposalinity), cascades (cellular pathways, photoinhibition, unfolded protein response, nitric oxide), endpoints (mechanisms loss, apoptosis, necrosis, exocytosis/vomocytosis). supported by direct evidence from cnidarian systems, indirectly through comparative evolutionary analyses non‐cnidarian systems. With this approach, new have been established between initiated different triggers. In particular, provide insights into poorly understood connections highlight role mechanism i.e. ‘symbiolysosomal digestion’, which symbiophagy. This review also increases approachability for specialists non‐specialists mapping vast landscape atlas comprehensible detailed models. We then discuss major knowledge gaps how future research may improve understanding cascade pathways (endpoints).

Language: Английский

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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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Cumulative risk of future bleaching for the world’s coral reefs

Science Advances, Journal Year: 2024, Volume and Issue: 10(26)

Published: June 26, 2024

Spatial and temporal patterns of future coral bleaching are uncertain, hampering global conservation efforts to protect reefs against climate change. Our analysis daily projections ocean warming establishes the severity, annual duration, onset severe risk for this century, pinpointing vital climatic refugia. We show that low-latitude regions most vulnerable thermal stress will experience little reprieve from mitigation. By 2080, is likely start on in spring, rather than late summer, with year-round anticipated be high some regardless mitigate harmful greenhouse gasses. identifying Earth's reef at lowest accelerated bleaching, our results prioritize limit loss biodiversity.

Language: Английский

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Symbiotic dinoflagellates divert energy away from mutualism during coral bleaching recovery

Symbiosis, Journal Year: 2023, Volume and Issue: 89(2), P. 173 - 186

Published: Jan. 28, 2023

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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High temporal resolution of hydrogen peroxide (H2O2) dynamics during heat stress does not support a causative role in coral bleaching

Coral Reefs, Journal Year: 2024, Volume and Issue: 43(1), P. 119 - 133

Published: Jan. 8, 2024

Abstract Human-induced climate change is causing ocean warming that triggers the breakdown of coral–algal symbiosis. The proximate cause this phenomenon, known as coral bleaching, commonly attributed to overproduction reactive oxygen species (ROS) by thermally stressed photosynthetic algal symbionts. However, direct evidence ROS production (e.g., in form H 2 O ) and physiological stress are ultimate bleaching remains ambiguous. Here, we investigated temporal dynamics (O concentrations during induced disentangle from consequence. Microsensors at tissue interface Pocillopora damicornis measured while exposing single nubbins baseline temperatures (30 °C) minor (33 °C), moderate (36 high (39 levels acute heat using Coral Bleaching Automated Stress System (CBASS). We show a temporary decline concentration, accompanied declining efficiency loss Symbiodiniaceae pigmentation, initial response thermal stress. This was neither provoked nor followed an increased concentration interface. A steady light-independent increase only detected stress, resulting complete permanent activity. Our findings do not support connection between photodamage suggest more research on function warranted. notion further substantiated observation additional source , likely oxidative bursts, were common temperature under their occurrence decreased Resolving multifaceted dynamic roles critical better understand holobiont identifying processes underlying

Language: Английский

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Past disturbances and local conditions influence the recovery rates of coral reefs

Global Change Biology, Journal Year: 2024, Volume and Issue: 30(1)

Published: Jan. 1, 2024

Corals are being increasingly subjected to marine heatwaves. Theory suggests that increasing the intensity of disturbances reduces recovery rates, which inspired us examine rates coral cover following heatwaves, cyclones, and other at 1921 study sites, in 58 countries three oceans, from 1977 2020. In Atlantic Ocean, has decreased fourfold since 1970s, have been relatively slow, except Antilles. By contrast, reefs Pacific Indian Oceans maintained over time. There were positive relationships between prior cyclone heatwave frequency, negative macroalgae distance shore. A recent increase variance some ecoregions those may be approaching a phase shift. While heatwaves our results suggest regional local conditions influence therefore, effective management efforts can help recover disturbances.

Language: Английский

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Physical and cellular impact of environmentally relevant microplastic exposure on thermally challenged Pocillopora damicornis (Cnidaria, Scleractinia)

The Science of The Total Environment, Journal Year: 2024, Volume and Issue: 918, P. 170651 - 170651

Published: Feb. 5, 2024

Microplastic pollution is an increasing threat to coral reefs, which are already strongly challenged by climate change-related heat stress. Although it known that scleractinian corals can ingest microplastic, little about their egestion and how microplastic exposure may impair at physiological cellular levels. In addition, the effects of current environmental concentration have been investigated date, particularly in impacted this study, combined these threats on Pocillopora damicornis were from a physical perspective. Colonies exposed three concentrations polyethylene beads (no beads: [No MP], 1 mg/L: [Low MP]; 10 [High MP]), two different temperatures (25 °C 30 °C) for 72 h. No visual signs stress corals, such as abnormal mucus production polyp extroflection, recorded. At adhered colonies ingested but also egested. Moreover, thermally stressed showed lower adhesion higher beads. Coral bleaching was observed with increase temperature bead concentration, indicated general decrease chlorophyll Symbiodiniaceae density. An lipid peroxidation measured MP] up-regulation response gene hsp70 due synergistic interaction both stressors. Overall, our findings still represents main P. damicornis, while effect microplastics health physiology be minor, especially control temperature. However, could exacerbate thermal homeostasis, even MP]. While reducing ocean warming critical preserving effective management emerging like equally essential.

Language: Английский

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Identifying regime shifts, transients and late warning signals for proactive ecosystem management

Biological Conservation, Journal Year: 2024, Volume and Issue: 290, P. 110433 - 110433

Published: Jan. 14, 2024

Conservation Biology fosters the study of Earth's ecosystems and biodiversity aiming at protecting species their habitats from menaces causing erosion biotic interactions extinctions. Its ultimate goal is to preserve promote sustainable ecological management maintaining both ecosystem's resilience services. Ecosystems display complex patterns in time space due intrinsic nonlinear nature can suffer regime shifts driven by agents global change. During last decades, Ecology has turned equilibrium metaphor paradigm non-equilibrium dynamics. This involves putting into scene multiple stable states, shifts, stochasticity, transients. These aspects are also crucial for biological conservation since they play a fundamental role species' persistence, ecosystems' resilience, detecting warning signals prior either collapse or recovery ecosystem. In this contribution, we discuss caused tipping points real ecosystems. Then, provide information on some known dynamical features theoretical ecology systems theory associated points, mainly given transient phenomena characteristic statistical tied early signals. illustrated with single-species mathematical model including facilitation immigration. We introduce evidence late as way identify when point been surpassed but system still remains state may be possible. Our main near concepts conservationist community bridges between such

Language: Английский

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