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Hynes MG, O'Dea A, Webster JM, Renema W. RADReef: A global Holocene Reef Rate of Accretion Dataset. Sci Data 2024; 11:398. [PMID: 38637551 PMCID: PMC11026384 DOI: 10.1038/s41597-024-03228-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Accepted: 04/04/2024] [Indexed: 04/20/2024] Open
Abstract
Reef cores are a powerful tool for investigating temporal changes in reef communities. Radiometric dating facilitates the determination of vertical accretion rates, which has allowed for examination of local-regional controlling factors, such as subsidence and sea level changes. Coral reefs must grow at sufficient rates to keep up with sea level rise, or risk 'drowning.' As sea level is expected to rise significantly in the next 100 years and beyond, it is important to understand whether reefs will be able to survive. Historical records of reef accretion rates extracted from cores provide valuable insights into extrinsic controlling factors of reef growth and are instrumental in helping predict if future reefs can accrete at rates needed to overcome predicted sea level changes. While extensive research exists at local and regional scales, limited attention has been given to identifying global patterns and drivers. To address this, we present "RADReef": A global dataset of dated Holocene reef cores. RADReef serves as a foundation for further research on past, present and future reef accretion.
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Affiliation(s)
- Michael G Hynes
- Naturalis Biodiversity Center, PO Box 9517, 2300RA, Leiden, The Netherlands.
- Institute for Biodiversity and Ecosystem Dynamics (IBED), Universiteit van Amsterdam, P.O. Box 94240, 1090GE, Amsterdam, The Netherlands.
| | - Aaron O'Dea
- Smithsonian Tropical Research Institute, Box 0843-03092, Balboa, Republic of Panama
- Sistema Nacional de Investigación, SENACYT, Clayton, Republic of Panama
| | - Jody M Webster
- Geocoastal Research Group, School of Geosciences, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Willem Renema
- Naturalis Biodiversity Center, PO Box 9517, 2300RA, Leiden, The Netherlands
- Institute for Biodiversity and Ecosystem Dynamics (IBED), Universiteit van Amsterdam, P.O. Box 94240, 1090GE, Amsterdam, The Netherlands
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2
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Hays GC, Laloë JO, Mortimer JA, Rattray A, Tromp JJ, Esteban N. Remote submerged banks and mesophotic ecosystems can provide key habitat for endangered marine megafauna. SCIENCE ADVANCES 2024; 10:eadl2838. [PMID: 38381823 PMCID: PMC10881038 DOI: 10.1126/sciadv.adl2838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 01/18/2024] [Indexed: 02/23/2024]
Abstract
The importance of some ecosystems remains poorly understood. We showed that mesophotic ecosystems (30 to 150 m) are a key habitat for a critically endangered species, with strong evidence that a globally important population of adult hawksbill turtles (Eretmochelys imbricata) almost exclusively foraged at these depths on remote submerged banks. This discovery highlights the need for such areas to be included in conservation planning, for example, as part of the United Nations High Seas Treaty. We equipped nesting turtles with Fastloc-GPS (Global Positioning System) satellite tags at an Indian Ocean breeding area and they all traveled to deep foraging sites (6765 days of tracking data across 22 individuals including 183,921 dive-depth measurements) rather than shallow coral reef sites. Both chart depths and depth data relayed from the tags indicated that turtles foraged at mesophotic depths, the modal dive depths being between 35 and 40 m. We calculate that 55,554 km2 of the western Indian Ocean alone consists of submerged banks between 30 and 60 m.
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Affiliation(s)
- Graeme C. Hays
- Deakin Marine Research and Innovation Centre, School of Life and Environmental Sciences, Deakin University, Geelong, Victoria, Australia
| | - Jacques-Olivier Laloë
- Deakin Marine Research and Innovation Centre, School of Life and Environmental Sciences, Deakin University, Geelong, Victoria, Australia
| | - Jeanne A. Mortimer
- Department of Biology, University of Florida, Gainesville, FL 32611, USA
- PO Box 1443, Victoria, Mahé, Seychelles
| | - Alex Rattray
- Deakin Marine Research and Innovation Centre, School of Life and Environmental Sciences, Deakin University, Geelong, Victoria, Australia
| | - Jared J. Tromp
- Deakin Marine Research and Innovation Centre, School of Life and Environmental Sciences, Deakin University, Geelong, Victoria, Australia
| | - Nicole Esteban
- Department of Biosciences, Swansea University, Swansea SA2 8PP, Wales, UK
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Castro-Cadenas MD, Loiseau C, Reimer JM, Claudet J. Tracking changes in social-ecological systems along environmental disturbances with the ocean health index. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 841:156423. [PMID: 35660614 DOI: 10.1016/j.scitotenv.2022.156423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 04/14/2022] [Accepted: 05/30/2022] [Indexed: 06/15/2023]
Abstract
The well-being of coastal communities is intimately tied to a healthy ocean, but coastal social-ecological systems are among the most vulnerable to global change. Improving the resilience of coastal communities requires an understanding of how local social-ecological systems respond to shocks to better inform decision-making and adapt local management interventions. However, assessments of social-ecological changes throughout a disturbance regime are scarce at the local level, although critical for efficient natural resource management and sustainable use of ocean ecosystem services. Here, we apply the Ocean Health Index (OHI) to assess the status of the marine social-ecological system of a tropical island (Moorea, French Polynesia), and track changes of the system before, during and after a disturbance regime. Our results show that while there are signs of social-ecological recovery, coastal protection was most affected along the disturbance, and that there is room for improvement toward biodiversity conservation. In addition, our study highlights some context-specific challenges associated with local OHI assessments, particularly those driven by limited fisheries data and appropriate reference point selection for coastal protection. Our results demonstrate the value of localized, regular OHI assessments through time to track changes in marine social-ecological systems, while uncovering important data gaps, to inform management at appropriate scales for decision-making.
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Affiliation(s)
- María D Castro-Cadenas
- National Center for Scientific Research, PSL Université Paris, CRIOBE, USR 3278 CNRS-EPHE-UPVD, Maison de l'Océan, 195 rue Saint-Jacques, 75005 Paris, France.
| | - Charles Loiseau
- National Center for Scientific Research, PSL Université Paris, CRIOBE, USR 3278 CNRS-EPHE-UPVD, Maison de l'Océan, 195 rue Saint-Jacques, 75005 Paris, France
| | - Julie M Reimer
- Department of Geography, Memorial University of Newfoundland, Newfoundland, Canada
| | - Joachim Claudet
- National Center for Scientific Research, PSL Université Paris, CRIOBE, USR 3278 CNRS-EPHE-UPVD, Maison de l'Océan, 195 rue Saint-Jacques, 75005 Paris, France; Laboratoire d'Excellence CORAIL, Moorea, French Polynesia
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Sannassy Pilly S, Richardson LE, Turner JR, Roche RC. Atoll-dependent variation in depth zonation of benthic communities on remote reefs. MARINE ENVIRONMENTAL RESEARCH 2022; 173:105520. [PMID: 34775207 DOI: 10.1016/j.marenvres.2021.105520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 11/01/2021] [Accepted: 11/03/2021] [Indexed: 06/13/2023]
Abstract
The distribution and organisation of benthic organisms on tropical reefs are typically heterogenous yet display distinct zonation patterns across depth gradients. However, there are few datasets which inform our understanding of how depth zonation in benthic community composition varies spatially among and within different reef systems. Here, we assess the depth zonation in benthic forereef slope communities in the Central Indian Ocean, prior to the back-to-back bleaching events in 2014-2017. We compare benthic communities between shallow (5-10 m) and deep (20-25 m) sites, at two spatial scales: among and within 4 atolls. Our analyses showed the variation in both major functional groups and hard coral assemblages between depth varied among atolls, and within-atoll comparisons revealed distinct differences between shallow and deep forereef slope communities. Indicator taxa analyses characterising the hard coral community between depths revealed a higher number of coral genera characteristic of the deep forereef slopes (10) than the shallow forereef slopes (6). Only two coral genera consistently associated with both depths across all atolls, and these were Acropora and Porites. Our results reveal spatial variation in depth zonation of benthic communities, potentially driven by biophysical processes varying across depths and atolls, and provide a baseline to understand and measure the impacts of future global climate change on benthic communities across depths.
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Cannon SE, Aram E, Beiateuea T, Kiareti A, Peter M, Donner SD. Coral reefs in the Gilbert Islands of Kiribati: Resistance, resilience, and recovery after more than a decade of multiple stressors. PLoS One 2021; 16:e0255304. [PMID: 34379665 PMCID: PMC8357116 DOI: 10.1371/journal.pone.0255304] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 07/13/2021] [Indexed: 11/19/2022] Open
Abstract
Coral reefs are increasingly affected by a combination of acute and chronic disturbances from climate change and local stressors. The coral reefs of the Republic of Kiribati’s Gilbert Islands are exposed to frequent heat stress caused by central-Pacific type El Niño events, and may provide a glimpse into the future of coral reefs in other parts of the world, where the frequency of heat stress events will likely increase due to climate change. Reefs in the Gilbert Islands experienced a series of acute disturbances over the past fifteen years, including mass coral bleaching in 2004–2005 and 2009–2010, and an outbreak of the corallivorous sea star Acanthaster cf solaris, or Crown-of-Thorns (CoTs), in 2014. The local chronic pressures including nutrient loading, sedimentation and fishing vary within the island chain, with highest pressures on the reefs in urbanized South Tarawa Atoll. In this study, we examine how recovery from acute disturbances differs across a gradient of human influence in neighboring Tarawa and Abaiang Atolls from 2012 through 2018. Benthic cover and size frequency data suggests that local coral communities have adjusted to the heat stress via shifts in the community composition to more temperature-tolerant taxa and individuals. In densely populated South Tarawa, we document a phase shift to the weedy and less bleaching-sensitive coral Porites rus, which accounted for 81% of all coral cover by 2018. By contrast, in less populated Abaiang, coral communities remained comparatively more diverse (with higher percentages of Pocillopora and the octocoral Heliopora) after the disturbances, but reefs had lower overall hard coral cover (18%) and were dominated by turf algae (41%). The CoTs outbreak caused a decline in the cover and mean size of massive Porites, the only taxa that was a ‘winner’ of the coral bleaching events in Abaiang. Although there are signs of recovery, the long-term trajectory of the benthic communities in Abaiang is not yet clear. We suggest three scenarios: they may remain in their current state (dominated by turf algae), undergo a phase shift to dominance by the macroalgae Halimeda, or recover to dominance by thermally tolerant hard coral genera. These findings provide a rare glimpse at the future of coral reefs around the world and the ways they may be affected by climate change, which may allow scientists to better predict how other reefs will respond to increasing heat stress events across gradients of local human disturbance.
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Affiliation(s)
- Sara E. Cannon
- Department of Geography, University of British Columbia, Vancouver, BC, Canada
- * E-mail:
| | - Erietera Aram
- Ministry of Fisheries and Marine Resource Development, Coastal Fisheries Division, Bikenibeui, Tarawa, Republic of Kiribati
| | - Toaea Beiateuea
- Ministry of Fisheries and Marine Resource Development, Coastal Fisheries Division, Bikenibeui, Tarawa, Republic of Kiribati
| | - Aranteiti Kiareti
- Ministry of Fisheries and Marine Resource Development, Coastal Fisheries Division, Bikenibeui, Tarawa, Republic of Kiribati
| | - Max Peter
- Ministry of Fisheries and Marine Resource Development, Coastal Fisheries Division, Bikenibeui, Tarawa, Republic of Kiribati
| | - Simon D. Donner
- Department of Geography, University of British Columbia, Vancouver, BC, Canada
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Kelman I, Ayeb-Karlsson S, Rose-Clarke K, Prost A, Ronneberg E, Wheeler N, Watts N. A review of mental health and wellbeing under climate change in small island developing states (SIDS). ENVIRONMENTAL RESEARCH LETTERS : ERL [WEB SITE] 2021; 16:033007. [PMID: 34149865 PMCID: PMC8208624 DOI: 10.1088/1748-9326/abe57d] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 02/07/2021] [Accepted: 02/11/2021] [Indexed: 05/03/2023]
Abstract
Small island developing states (SIDS) are often at the forefront of climate change impacts, including those related to health, but information on mental health and wellbeing is typically underreported. To help address this research lacuna, this paper reviews research about mental health and wellbeing under climate change in SIDS. Due to major differences in the literature's methodologies, results, and analyses, the method is an overview and qualitative evidence synthesis of peer-reviewed publications. The findings show that mental health and wellbeing in the context of climate change have yet to feature prominently and systematically in research covering SIDS. It seems likely that major adverse mental health and wellbeing impacts linked to climate change impacts will affect SIDS peoples. Similar outcomes might also emerge when discussing climate change related situations, scenarios, and responses, irrespective of what has actually happened thus far due to climate change. In the context of inadequate health systems and stigmatisation of mental health diagnoses and treatments, as tends to occur globally, climate change narratives might present an opening for conversations about addressing mental health and wellbeing issues for SIDS.
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Affiliation(s)
- Ilan Kelman
- University College London (UCL), London, United Kingdom
- University of Agder, 4630 Kristiansand, Norway
| | - Sonja Ayeb-Karlsson
- University of Sussex, Brighton BN1 9RH, United Kingdom
- United Nations University Institute for Environment and Human Security, D-53113 Bonn, Germany
| | | | - Audrey Prost
- University College London (UCL), London, United Kingdom
| | - Espen Ronneberg
- Secretariat of the Pacific Regional Environment Programme (SPREP), Apia, Samoa
| | - Nicola Wheeler
- Consultant (World Health Organization), Associate (Outsight International), London, United Kingdom
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Chen T, Li S, Zhao J, Feng Y. Uranium-thorium dating of coral mortality and community shift in a highly disturbed inshore reef (Weizhou Island, northern South China Sea). THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 752:141866. [PMID: 32889282 DOI: 10.1016/j.scitotenv.2020.141866] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 08/19/2020] [Accepted: 08/19/2020] [Indexed: 06/11/2023]
Abstract
Inshore coral habitats are at high risk of loss due to a combination of climate warming and regional-scale human impacts. As a result, they have undergone significant declines. Direct evidence of acute and chronic disturbance on most inshore coral assemblages is limited. Long-term, periodical surveys and historical baseline data essential for effective management are lacking. Using high-precision uranium-thorium (UTh) dating, we reconstruct a ~100-year-long history of extensive coral loss, changes in coral community structure, and a shifting baseline. The data were collected at Weizhou Island, northern South China Sea (SCS), which has highly disturbed inshore coral habitats that are typical globally. According to our UTh dates, major coral mortalities around Weizhou Island have occurred since the 1950s, with increasing frequency and severity since the 1980s. The extensive loss of branching Acropora and collapse of coral communities with peaks around 1960, 1984, and 1998 are accompanied by a shift toward low coral cover and noncoral-dominated assemblages. Prior to this collapse, the local coral community structure sustained remarkable long-term stability over millennia. The timing of the Acropora loss and massive coral mortalities coincides with multiple acute and chronic, natural and anthropogenic disturbance events. We suggest that priority should be given to directly addressing the causes of degradation and effectively controlling chronic disturbances before attempting to restore reef ecosystems. This is probably the only way to solve the "wicked problem" of sustaining the key functions and ecosystem services of inshore coral habitats such as those of Weizhou Island, northern SCS.
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Affiliation(s)
- Tianran Chen
- Key Laboratory of Ocean and Marginal Sea Geology, South China Sea Institute of Oceanology, Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Sciences, Guangzhou 510301, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou 511458, China.
| | - Shu Li
- Key Laboratory of Ocean and Marginal Sea Geology, South China Sea Institute of Oceanology, Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Sciences, Guangzhou 510301, China.
| | - Jianxin Zhao
- Radiogenic Isotope Facility, School of Earth and Environmental Sciences, University of Queensland, St Lucia, Queensland 4072, Australia
| | - Yuexing Feng
- Radiogenic Isotope Facility, School of Earth and Environmental Sciences, University of Queensland, St Lucia, Queensland 4072, Australia
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Romero-Torres M, Acosta A, Palacio-Castro AM, Treml EA, Zapata FA, Paz-García DA, Porter JW. Coral reef resilience to thermal stress in the Eastern Tropical Pacific. GLOBAL CHANGE BIOLOGY 2020; 26:3880-3890. [PMID: 32315464 DOI: 10.1111/gcb.15126] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 04/12/2020] [Accepted: 04/14/2020] [Indexed: 06/11/2023]
Abstract
Coral reefs worldwide are threatened by thermal stress caused by climate change. Especially devastating periods of coral loss frequently occur during El Niño-Southern Oscillation (ENSO) events originating in the Eastern Tropical Pacific (ETP). El Niño-induced thermal stress is considered the primary threat to ETP coral reefs. An increase in the frequency and intensity of ENSO events predicted in the coming decades threatens a pan-tropical collapse of coral reefs. During the 1982-1983 El Niño, most reefs in the Galapagos Islands collapsed, and many more in the region were decimated by massive coral bleaching and mortality. However, after repeated thermal stress disturbances, such as those caused by the 1997-1998 El Niño, ETP corals reefs have demonstrated regional persistence and resiliency. Using a 44 year dataset (1970-2014) of live coral cover from the ETP, we assess whether ETP reefs exhibit the same decline as seen globally for other reefs. Also, we compare the ETP live coral cover rate of change with data from the maximum Degree Heating Weeks experienced by these reefs to assess the role of thermal stress on coral reef survival. We find that during the period 1970-2014, ETP coral cover exhibited temporary reductions following major ENSO events, but no overall decline. Further, we find that ETP reef recovery patterns allow coral to persist under these El Niño-stressed conditions, often recovering from these events in 10-15 years. Accumulative heat stress explains 31% of the overall annual rate of change of living coral cover in the ETP. This suggests that ETP coral reefs have adapted to thermal extremes to date, and may have the ability to adapt to near-term future climate-change thermal anomalies. These findings for ETP reef resilience may provide general insights for the future of coral reef survival and recovery elsewhere under intensifying El Niño scenarios.
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Affiliation(s)
- Mauricio Romero-Torres
- Unidad de Ecología y Sistemática (UNESIS), Departamento de Biología, Pontificia Universidad Javeriana, Bogotá, Colombia
- Unidad Nacional para la Gestión del Riesgo de Desastres (UNGRD), Bogotá, Colombia
- School of BioSciences, University of Melbourne, Melbourne, Vic., Australia
| | - Alberto Acosta
- Unidad de Ecología y Sistemática (UNESIS), Departamento de Biología, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Ana M Palacio-Castro
- Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA
- Atlantic Oceanographic and Meteorological Laboratory, National Oceanographic and Atmospheric Administration, Miami, FL, USA
| | - Eric A Treml
- School of BioSciences, University of Melbourne, Melbourne, Vic., Australia
- School of Life and Environmental Sciences, Deakin University, Waurn Ponds, Vic., Australia
| | - Fernando A Zapata
- Grupo de Investigación en Ecología de Arrecifes Coralinos, Departamento de Biología, Universidad del Valle, Cali, Colombia
| | - David A Paz-García
- CONACyT, Centro de Investigaciones Biológicas del Noroeste (CIBNOR), La Paz, BCS, Mexico
| | - James W Porter
- Odum School of Ecology, University of Georgia, Athens, GA, USA
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de Bakker DM, van Duyl FC, Perry CT, Meesters EH. Extreme spatial heterogeneity in carbonate accretion potential on a Caribbean fringing reef linked to local human disturbance gradients. GLOBAL CHANGE BIOLOGY 2019; 25:4092-4104. [PMID: 31566878 PMCID: PMC6899606 DOI: 10.1111/gcb.14800] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 06/26/2019] [Accepted: 08/05/2019] [Indexed: 05/22/2023]
Abstract
The capacity of coral reefs to maintain their structurally complex frameworks and to retain the potential for vertical accretion is vitally important to the persistence of their ecological functioning and the ecosystem services they sustain. However, datasets to support detailed along-coast assessments of framework production rates and accretion potential do not presently exist. Here, we estimate, based on gross bioaccretion and bioerosion measures, the carbonate budgets and resultant estimated accretion rates (EAR) of the shallow reef zone of leeward Bonaire - between 5 and 12 m depth - at unique fine spatial resolution along this coast (115 sites). Whilst the fringing reef of Bonaire is often reported to be in a better ecological condition than most sites throughout the wider Caribbean region, our data show that the carbonate budgets of the reefs and derived EAR varied considerably across this ~58 km long fringing reef complex. Some areas, in particular the marine reserves, were indeed still dominated by structurally complex coral communities with high net carbonate production (>10 kg CaCO3 m-2 year-1 ), high live coral cover and complex structural topography. The majority of the studied sites, however, were defined by relatively low budget states (<2 kg CaCO3 m-2 year-1 ) or were in a state of net erosion. These data highlight the marked spatial heterogeneity that can occur in budget states, and thus in reef accretion potential, even between quite closely spaced areas of individual reef complexes. This heterogeneity is linked strongly to the degree of localized land-based impacts along the coast, and resultant differences in the abundance of reef framework building coral species. The major impact of this variability is that those sections of reef defined by low-accretion rates will have limited capacity to maintain their structural integrity and to keep pace with current projections of climate change induced sea-level rise (SLR), thus posing a threat to reef functioning and biodiversity, potentially leading to trophic cascades. Since many Caribbean reefs are more severely degraded than those found around Bonaire, it is to be expected that the findings presented here are rather the rule than the exception, but the study also highlights the need for similar high spatial resolution (along-coast) assessments of budget states and accretion rates to meaningfully explore increasing coastal risk at the country level. The findings also more generally underline the significance of reducing local anthropogenic disturbance and restoring framework building coral assemblages. Appropriately focussed local preservation efforts may aid in averting future large-scale above reef water depth increases on Caribbean coral reefs and will limit the social and economic implications associated with the loss of reef goods and services.
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Affiliation(s)
- Didier M. de Bakker
- Wageningen Marine ResearchDen HelderThe Netherlands
- Marine Microbiology and BiogeochemistryNIOZ Royal Netherlands Institute for Sea Research and Utrecht UniversityTexelThe Netherlands
| | - Fleur C. van Duyl
- Marine Microbiology and BiogeochemistryNIOZ Royal Netherlands Institute for Sea Research and Utrecht UniversityTexelThe Netherlands
| | - Chris T. Perry
- GeographyCollege of Life and Environmental SciencesUniversity of ExeterExeterUK
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Fine M, Hoegh-Guldberg O, Meroz-Fine E, Dove S. Ecological changes over 90 years at Low Isles on the Great Barrier Reef. Nat Commun 2019; 10:4409. [PMID: 31562327 PMCID: PMC6765017 DOI: 10.1038/s41467-019-12431-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 09/09/2019] [Indexed: 11/23/2022] Open
Abstract
Coral reefs are under increasing stress from local and global factors. Long-term perspectives are becoming increasingly important for understanding ecosystem responses. Here, we provide insights from a 91-year study of the Low Isles on the northern Great Barrier Reef (GBR) that begins with the pioneering Great Barrier Reef Expedition (1928-29). We show that intertidal communities have experienced major phase-shifts since 1928, with few signs of a return to the initial state. Coral communities demolished by cyclones 50 years ago and exposed to multiple stressors have yet to recover. Richness and diversity of these communities systematically declined for corals and other invertebrates. Specifically, massive corals have replaced branching corals, and soft corals have become much more numerous. The long-term perspective of this study illustrates the importance of considering multiple factors in reef decline, and potential recovery, of coral reefs, and the importance of tracking changes in community structure as well as coral abundance over long periods. Predictions of coral reef dynamics under climate change are hindered by lack of long-term records. Here the authors couple historical and re-survey data from the Great Barrier Reef to show major phase-shifts in the coral and non-coral community over the last 90 years.
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Affiliation(s)
- Maoz Fine
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, 52900, Ramat-Gan, Israel. .,The Interuniversity Institute for Marine Science, P.O. Box 469, 8810300, Eilat, Israel.
| | - Ove Hoegh-Guldberg
- School of Biological Sciences, The University of Queensland, St. Lucia, QLD, 4072, Australia.,Global Change Institute, University of Queensland, St. Lucia, QLD, 4072, Australia
| | - Efrat Meroz-Fine
- The Interuniversity Institute for Marine Science, P.O. Box 469, 8810300, Eilat, Israel
| | - Sophie Dove
- School of Biological Sciences, The University of Queensland, St. Lucia, QLD, 4072, Australia.,Global Change Institute, University of Queensland, St. Lucia, QLD, 4072, Australia
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11
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The Status of Coral Reefs and Its Importance for Coastal Protection: A Case Study of Northeastern Hainan Island, South China Sea. SUSTAINABILITY 2019. [DOI: 10.3390/su11164354] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This study evaluated the status of coral communities at the fringing reefs in the northern South China Sea, and their potential role in maintaining nearby coastline stability of northeastern Hainan Island (Puqian Bay, Hainan Bay). Thirty-nine coral species were recorded with mean coral cover of 5.3%, and are dominated by massive Galaxea, Platygyra and Porites. The coral communities were clustered into two groups (Clu-HNB and Clu-PQB) corresponding to different stable coastal conditions. Coral communities at the Hainan Bay with higher diversity and greater cover corresponded to relatively stable coastline, whereas those at the southern Puqian Bay (with the lowest coral diversity and spatial coverage) corresponded to severe coastline erosion. This work provides some direct evidence that declined coral reefs would weaken their functions to maintain a stable coastline, resulting in severe coastal erosion. It is also useful to help coastal managers and local people pay more attention to the importance of coral reefs in coastal protection and encourage them to change their ways to get sustainable use of coral reef resources. It may be beneficial to inspire or initiate coastal engineering to manage coasts with natural coral reef solution.
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12
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Darling ES, McClanahan TR, Maina J, Gurney GG, Graham NAJ, Januchowski-Hartley F, Cinner JE, Mora C, Hicks CC, Maire E, Puotinen M, Skirving WJ, Adjeroud M, Ahmadia G, Arthur R, Bauman AG, Beger M, Berumen ML, Bigot L, Bouwmeester J, Brenier A, Bridge TCL, Brown E, Campbell SJ, Cannon S, Cauvin B, Chen CA, Claudet J, Denis V, Donner S, Estradivari, Fadli N, Feary DA, Fenner D, Fox H, Franklin EC, Friedlander A, Gilmour J, Goiran C, Guest J, Hobbs JPA, Hoey AS, Houk P, Johnson S, Jupiter SD, Kayal M, Kuo CY, Lamb J, Lee MAC, Low J, Muthiga N, Muttaqin E, Nand Y, Nash KL, Nedlic O, Pandolfi JM, Pardede S, Patankar V, Penin L, Ribas-Deulofeu L, Richards Z, Roberts TE, Rodgers KS, Safuan CDM, Sala E, Shedrawi G, Sin TM, Smallhorn-West P, Smith JE, Sommer B, Steinberg PD, Sutthacheep M, Tan CHJ, Williams GJ, Wilson S, Yeemin T, Bruno JF, Fortin MJ, Krkosek M, Mouillot D. Social–environmental drivers inform strategic management of coral reefs in the Anthropocene. Nat Ecol Evol 2019; 3:1341-1350. [DOI: 10.1038/s41559-019-0953-8] [Citation(s) in RCA: 111] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 06/24/2019] [Indexed: 01/23/2023]
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13
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Ryan EJ, Hanmer K, Kench PS. Massive corals maintain a positive carbonate budget of a Maldivian upper reef platform despite major bleaching event. Sci Rep 2019; 9:6515. [PMID: 31019243 PMCID: PMC6482145 DOI: 10.1038/s41598-019-42985-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 04/12/2019] [Indexed: 11/09/2022] Open
Abstract
Coral reefs experienced the third global bleaching event in 2015–2016 due to high sea-surface temperature (SST) anomalies. Declines in net carbonate production associated with coral bleaching are implicated in reef structural collapse and cascading impacts for adjacent coral reef islands. We present the first carbonate budget study of a reef platform surface (reef crest and reef flat) in the southern Maldives and the first record of upper reef flat condition in the central Indian Ocean post the 2015–2016 coral bleaching event. Scleractinian corals were the primary carbonate producers, with live coral cover averaging between 11.1 ± 6.5 and 31.2 ± 21.8% and dominated by massive corals. Gross carbonate production rates averaged 5.9 ± 2.5 G (kg CaCO3 m2 yr−1). Bioerosion was estimated at 3.4 ± 0.4 G, resulting in an average net carbonate production rate of 2.5 ± 2.4 G. Comparison of results with a study of the fore-reef slope highlights major differences in post-bleaching carbonate budget state between the fore-reef slope and the reef platform surface. The positive reef flat carbonate budget is attributed to the persistence of massive corals (Porites spp. and Heliopora spp.) through the bleaching event.
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Affiliation(s)
- E J Ryan
- School of Environment, the University of Auckland, Auckland, 1010, New Zealand.
| | - K Hanmer
- School of Environment, the University of Auckland, Auckland, 1010, New Zealand
| | - P S Kench
- School of Environment, the University of Auckland, Auckland, 1010, New Zealand.,Department of Earth Sciences, Simon Fraser University, Burnaby, BC, Canada
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14
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Mcleod E, Anthony KRN, Mumby PJ, Maynard J, Beeden R, Graham NAJ, Heron SF, Hoegh-Guldberg O, Jupiter S, MacGowan P, Mangubhai S, Marshall N, Marshall PA, McClanahan TR, Mcleod K, Nyström M, Obura D, Parker B, Possingham HP, Salm RV, Tamelander J. The future of resilience-based management in coral reef ecosystems. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 233:291-301. [PMID: 30583103 DOI: 10.1016/j.jenvman.2018.11.034] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 10/26/2018] [Accepted: 11/10/2018] [Indexed: 05/12/2023]
Abstract
Resilience underpins the sustainability of both ecological and social systems. Extensive loss of reef corals following recent mass bleaching events have challenged the notion that support of system resilience is a viable reef management strategy. While resilience-based management (RBM) cannot prevent the damaging effects of major disturbances, such as mass bleaching events, it can support natural processes that promote resistance and recovery. Here, we review the potential of RBM to help sustain coral reefs in the 21st century. We explore the scope for supporting resilience through existing management approaches and emerging technologies and discuss their opportunities and limitations in a changing climate. We argue that for RBM to be effective in a changing world, reef management strategies need to involve both existing and new interventions that together reduce stress, support the fitness of populations and species, and help people and economies to adapt to a highly altered ecosystem.
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Affiliation(s)
| | - Kenneth R N Anthony
- Australian Institute of Marine Science, PMB 3, Townsville, Qld, 4810, Australia; Marine Spatial Ecology Lab, School of Biological Sciences, The University of Queensland, St. Lucia, Qld, 4072, Australia
| | - Peter J Mumby
- Marine Spatial Ecology Lab, School of Biological Sciences, The University of Queensland, St. Lucia, Qld, 4072, Australia
| | - Jeffrey Maynard
- SymbioSeas and the Marine Applied Research Center, Wilmington, NC, 28411, United States
| | - Roger Beeden
- Great Barrier Reef Marine Park Authority, Townsville, Qld, 4810, Australia
| | | | - Scott F Heron
- NOAA Coral Reef Watch, NESDIS Center for Satellite Applications and Research, College Park, MD, 20740, USA; ReefSense, Townsville, Qld 4814, Australia; Marine Geophysical Laboratory, Physics Department, College of Science, Technology and Engineering, James Cook University, Townsville, Qld, 4811, Australia
| | - Ove Hoegh-Guldberg
- Global Change Institute, University of Queensland, St Lucia, 4072, Qld, Australia
| | - Stacy Jupiter
- Wildlife Conservation Society, Melanesia Program, Suva, Fiji
| | | | | | - Nadine Marshall
- CSIRO Land and Water and College of Science and Engineering, James Cook University, Townsville, Q4811, Australia
| | - Paul A Marshall
- Centre for Biodiversity and Conservation Science, University of Queensland, St. Lucia, Qld, 4072, Australia; Reef Ecologic, North Ward, Townsville, Qld, 4810, Australia
| | | | - Karen Mcleod
- COMPASS, Oregon State University, Department of Zoology, Corvallis, OR, USA
| | - Magnus Nyström
- Stockholm Resilience Centre, Stockholm University, Stockholm, SE, 10691, Sweden
| | - David Obura
- CORDIO East Africa, Mombasa, Kenya; Global Change Institute, University of Queensland, St Lucia, 4072, Qld, Australia
| | - Britt Parker
- NOAA NIDIS/Cooperative Institute for Research In Environmental Sciences, University of Colorado Boulder, Boulder, Colorado, USA
| | - Hugh P Possingham
- The Nature Conservancy, Arlington, VA, 22203, USA; The University of Queensland, Brisbane, 4072, Australia
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15
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Perry CT, Alvarez‐Filip L. Changing geo‐ecological functions of coral reefs in the Anthropocene. Funct Ecol 2018. [DOI: 10.1111/1365-2435.13247] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Chris T. Perry
- Geography College of Life and Environmental Sciences University of Exeter Exeter UK
| | - Lorenzo Alvarez‐Filip
- Biodiversity and Reef Conservation Laboratory Unidad Académica de Sistemas Arrecifales Instituto de Ciencias del Mar y Limnología Universidad Nacional Autónoma de Mexico Puerto Morelos Quintana Roo Mexico
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16
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van Heuven SMAC, Webb AE, de Bakker DM, Meesters E, van Duyl FC, Reichart GJ, de Nooijer LJ. In-situ incubation of a coral patch for community-scale assessment of metabolic and chemical processes on a reef slope. PeerJ 2018; 6:e5966. [PMID: 30533295 PMCID: PMC6282943 DOI: 10.7717/peerj.5966] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 10/18/2018] [Indexed: 11/24/2022] Open
Abstract
Anthropogenic pressures threaten the health of coral reefs globally. Some of these pressures directly affect coral functioning, while others are indirect, for example by promoting the capacity of bioeroders to dissolve coral aragonite. To assess the coral reef status, it is necessary to validate community-scale measurements of metabolic and geochemical processes in the field, by determining fluxes from enclosed coral reef patches. Here, we investigate diurnal trends of carbonate chemistry, dissolved organic carbon, oxygen, and nutrients on a 20 m deep coral reef patch offshore from the island of Saba, Dutch Caribbean by means of tent incubations. The obtained trends are related to benthic carbon fluxes by quantifying net community calcification (NCC) and net community production (NCP). The relatively strong currents and swell-induced near-bottom surge at this location caused minor seawater exchange between the incubated reef and ambient water. Employing a compensating interpretive model, the exchange is used to our advantage as it maintains reasonably ventilated conditions, which conceivably prevents metabolic arrest during incubation periods of multiple hours. No diurnal trends in carbonate chemistry were detected and all net diurnal rates of production were strongly skewed towards respiration suggesting net heterotrophy in all incubations. The NCC inferred from our incubations ranges from −0.2 to 1.4 mmol CaCO3 m−2 h−1 (−0.2 to 1.2 kg CaCO3 m−2 year−1) and NCP varies from −9 to −21.7 mmol m−2 h−1 (net respiration). When comparing to the consensus-based ReefBudget approach, the estimated NCC rate for the incubated full planar area (0.36 kg CaCO3 m−2 year−1) was lower, but still within range of the different NCC inferred from our incubations. Field trials indicate that the tent-based incubation as presented here, coupled with an appropriate interpretive model, is an effective tool to investigate, in situ, the state of coral reef patches even when located in a relatively hydrodynamic environment.
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Affiliation(s)
- Steven M A C van Heuven
- Department of Ocean Sciences, NIOZ Royal Netherlands Institute for Sea Research, and Utrecht University, Den Hoorn, Noord-Holland, The Netherlands
| | - Alice E Webb
- Department of Ocean Sciences, NIOZ Royal Netherlands Institute for Sea Research, and Utrecht University, Den Hoorn, Noord-Holland, The Netherlands
| | - Didier M de Bakker
- Department of Marine Microbiology, NIOZ Royal Netherlands Institute for Sea Research, and Utrecht University, Den Hoorn, Noord-Holland, The Netherlands.,Wageningen Marine Research, Wageningen University and Research, Den Helder, Noord-Holland, The Netherlands
| | - Erik Meesters
- Wageningen Marine Research, Wageningen University and Research, Den Helder, Noord-Holland, The Netherlands
| | - Fleur C van Duyl
- Department of Marine Microbiology, NIOZ Royal Netherlands Institute for Sea Research, and Utrecht University, Den Hoorn, Noord-Holland, The Netherlands
| | - Gert-Jan Reichart
- Department of Ocean Sciences, NIOZ Royal Netherlands Institute for Sea Research, and Utrecht University, Den Hoorn, Noord-Holland, The Netherlands.,Department of Earth Sciences, Utrecht University, Utrecht, Utrecht, The Netherlands
| | - Lennart J de Nooijer
- Department of Ocean Sciences, NIOZ Royal Netherlands Institute for Sea Research, and Utrecht University, Den Hoorn, Noord-Holland, The Netherlands
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17
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Tebbett SB, Bellwood DR. Functional links on coral reefs: Urchins and triggerfishes, a cautionary tale. MARINE ENVIRONMENTAL RESEARCH 2018; 141:255-263. [PMID: 30249458 DOI: 10.1016/j.marenvres.2018.09.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 09/05/2018] [Accepted: 09/09/2018] [Indexed: 06/08/2023]
Abstract
Urchins are ubiquitous components of coral reefs ecosystems, with significant roles in bioerosion and herbivory. By controlling urchin densities, triggerfishes have been identified as keystone predators. However, the functional linkages between urchins and triggerfishes, in terms of distributional patterns and concomitant effects on ecosystem processes, are not well understood, especially in relatively unexploited systems. To address this we censused urchins and triggerfishes on two cross-shelf surveys on the Great Barrier Reef (GBR) at the same times and locations. We also evaluated the role of urchins in bioerosion. Although urchin abundance and triggerfish biomass varied by 80% and nearly 900% across sites, respectively, this variability was driven primarily by shelf position with no evidence of top-down control on urchins by triggerfishes. Low urchin abundances meant urchins only played a minor role in bioerosion. We highlight the potential variability in functional links, and contributions to ecosystem processes, among regions.
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Affiliation(s)
- Sterling B Tebbett
- ARC Centre of Excellence for Coral Reef Studies, College of Science and Engineering, James Cook University, Townsville, Queensland, 4811, Australia.
| | - David R Bellwood
- ARC Centre of Excellence for Coral Reef Studies, College of Science and Engineering, James Cook University, Townsville, Queensland, 4811, Australia
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18
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Beale DJ, Crosswell J, Karpe AV, Metcalfe SS, Morrison PD, Staley C, Ahmed W, Sadowsky MJ, Palombo EA, Steven ADL. Seasonal metabolic analysis of marine sediments collected from Moreton Bay in South East Queensland, Australia, using a multi-omics-based approach. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 631-632:1328-1341. [PMID: 29727957 DOI: 10.1016/j.scitotenv.2018.03.106] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 03/06/2018] [Accepted: 03/09/2018] [Indexed: 06/08/2023]
Abstract
Anthropogenic effects of urban density have altered natural ecosystems. Such changes include eutrophication of freshwater and adjoining coastal habitats, and increased levels of inorganic nutrients and pollutants into waterways. In Australia, these changes are intensified by large-scale ocean-atmospheric events, leading to considerable abiotic stress on the natural flora and fauna. Bacterial communities in marine sediments from Moreton Bay (South East Queensland, Australia) were examined in order to assess the impact of rainfall changes, chemical pollution, and subsequent abiotic stress on living organisms within a marine ecosystem. Sediments were collected during the wet and dry seasons and analyzed using bacterial metagenomics and community metabolomics techniques. Physicochemical data were also analyzed to account for biological variance that may be due to non-rainfall-based abiotic stresses. Wet-dry seasonality was the dominant control on bacterial community structure and metabolic function. Changes in the availability of nutrients, organic matter and light appeared to be the major seasonal stressors. In contrast, urban and industrial pollutants appeared to be minor stressors at the sites sampled. During the wet season, the bacterial community composition reflected organisms that utilize biogeochemical pathways with fast kinetics, such as aerobic metabolism, direct assimilation of inorganic compounds, and primary production. The transition to the dry season saw the bacterial community composition shift towards organisms that utilize more complex organic energy sources, such as carbohydrates and fatty acids, and anaerobic redox processes.
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Affiliation(s)
- D J Beale
- CSIRO Land & Water, Ecosciences Precinct, Dutton Park, QLD 4102, Australia.
| | - J Crosswell
- CSIRO Oceans & Atmosphere, Ecosciences Precinct, Dutton Park, QLD 4102, Australia.
| | - A V Karpe
- CSIRO Land & Water, Ecosciences Precinct, Dutton Park, QLD 4102, Australia.
| | - S S Metcalfe
- CSIRO Land & Water, Ecosciences Precinct, Dutton Park, QLD 4102, Australia.
| | - P D Morrison
- Australian Centre for Research on Separation Science, School of Applied Sciences, RMIT University, Melbourne, VIC 3001, Australia.
| | - C Staley
- Biotechnology Institute, University of Minnesota, St. Paul, MN, United States.
| | - W Ahmed
- CSIRO Land & Water, Ecosciences Precinct, Dutton Park, QLD 4102, Australia.
| | - M J Sadowsky
- Biotechnology Institute, University of Minnesota, St. Paul, MN, United States.
| | - E A Palombo
- Faculty of Science, Engineering and Technology, Swinburne University of Technology, Hawthorn, VIC 3122, Australia.
| | - A D L Steven
- CSIRO Oceans & Atmosphere, Ecosciences Precinct, Dutton Park, QLD 4102, Australia.
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19
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Loss of coral reef growth capacity to track future increases in sea level. Nature 2018; 558:396-400. [PMID: 29904103 DOI: 10.1038/s41586-018-0194-z] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 05/09/2018] [Indexed: 01/01/2023]
Abstract
Sea-level rise (SLR) is predicted to elevate water depths above coral reefs and to increase coastal wave exposure as ecological degradation limits vertical reef growth, but projections lack data on interactions between local rates of reef growth and sea level rise. Here we calculate the vertical growth potential of more than 200 tropical western Atlantic and Indian Ocean reefs, and compare these against recent and projected rates of SLR under different Representative Concentration Pathway (RCP) scenarios. Although many reefs retain accretion rates close to recent SLR trends, few will have the capacity to track SLR projections under RCP4.5 scenarios without sustained ecological recovery, and under RCP8.5 scenarios most reefs are predicted to experience mean water depth increases of more than 0.5 m by 2100. Coral cover strongly predicts reef capacity to track SLR, but threshold cover levels that will be necessary to prevent submergence are well above those observed on most reefs. Urgent action is thus needed to mitigate climate, sea-level and future ecological changes in order to limit the magnitude of future reef submergence.
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20
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van Woesik R, Cacciapaglia CW. Keeping up with sea-level rise: Carbonate production rates in Palau and Yap, western Pacific Ocean. PLoS One 2018; 13:e0197077. [PMID: 29738545 PMCID: PMC5940225 DOI: 10.1371/journal.pone.0197077] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 04/25/2018] [Indexed: 11/18/2022] Open
Abstract
Coral reefs protect islands from tropical storm waves and provide goods and services for millions of islanders worldwide. Yet it is unknown how coral reefs in general, and carbonate production in particular, will respond to sea-level rise and thermal stress associated with climate change. This study compared the reef-building capacity of different shallow-water habitats at twenty-four sites on each of two islands, Palau and Yap, in the western Pacific Ocean. We were particularly interested in estimating the inverse problem of calculating the value of live coral cover at which net carbonate production becomes negative, and whether that value varied across habitats. Net carbonate production varied among habitats, averaging 10.2 kg CaCO3 m-2 y-1 for outer reefs, 12.7 kg CaCO3 m-2 y-1 for patch reefs, and 7.2 kg CaCO3 m-2 y-1 for inner reefs. The value of live coral cover at which net carbonate production became negative varied across habitats, with highest values on inner reefs. These results suggest that some inner reefs tend to produce less carbonate, and therefore need higher coral cover to produce enough carbonate to keep up with sea-level rise than outer and patch reefs. These results also suggest that inner reefs are more vulnerable to sea-level rise than other habitats, which stresses the need for effective land-use practices as the climate continues to change. Averaging across all reef habitats, the rate of carbonate production was 9.7 kg CaCO3 m-2 y-1, or approximately 7.9 mm y-1 of potential vertical accretion. Such rates of vertical accretion are higher than projected averages of sea-level rise for the representative concentration pathway (RCP) climate-change scenarios 2.6, 4.5, and 6, but lower than for the RCP scenario 8.5.
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Affiliation(s)
- Robert van Woesik
- Department of Biological Sciences, Florida Institute of Technology, West University Blvd., Melbourne, Florida, United States of America
- * E-mail:
| | - Christopher William Cacciapaglia
- Department of Biological Sciences, Florida Institute of Technology, West University Blvd., Melbourne, Florida, United States of America
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21
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Harris DL, Rovere A, Casella E, Power H, Canavesio R, Collin A, Pomeroy A, Webster JM, Parravicini V. Coral reef structural complexity provides important coastal protection from waves under rising sea levels. SCIENCE ADVANCES 2018; 4:eaao4350. [PMID: 29503866 PMCID: PMC5829992 DOI: 10.1126/sciadv.aao4350] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 01/24/2018] [Indexed: 05/06/2023]
Abstract
Coral reefs are diverse ecosystems that support millions of people worldwide by providing coastal protection from waves. Climate change and human impacts are leading to degraded coral reefs and to rising sea levels, posing concerns for the protection of tropical coastal regions in the near future. We use a wave dissipation model calibrated with empirical wave data to calculate the future increase of back-reef wave height. We show that, in the near future, the structural complexity of coral reefs is more important than sea-level rise in determining the coastal protection provided by coral reefs from average waves. We also show that a significant increase in average wave heights could occur at present sea level if there is sustained degradation of benthic structural complexity. Our results highlight that maintaining the structural complexity of coral reefs is key to ensure coastal protection on tropical coastlines in the future.
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Affiliation(s)
- Daniel L. Harris
- Center for Marine Environmental Sciences (MARUM), Bremen University, Bremen, Germany
- Leibniz Centre for Tropical Marine Research, Bremen, Germany
- The University of Queensland, School of Earth and Environmental Sciences, Brisbane, Queensland, Australia
- Corresponding author.
| | - Alessio Rovere
- Center for Marine Environmental Sciences (MARUM), Bremen University, Bremen, Germany
- Leibniz Centre for Tropical Marine Research, Bremen, Germany
- Lamont-Doherty Earth Observatory, Columbia University, New York, NY 10964, USA
| | - Elisa Casella
- Leibniz Centre for Tropical Marine Research, Bremen, Germany
| | - Hannah Power
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, New South Wales, Australia
| | - Remy Canavesio
- Centre de Recherches Insulaires et Observatoire de l’Environnement, USR 3278 CNRS–École Pratique des Hautes Études (EPHE)–Université de Perpignan Via Domitia, Laboratoire d’Excellence (LabEX) “CORAIL,” University of Perpignan, 66860 Perpignan, France
| | - Antoine Collin
- EPHE, PSL Research University, CNRS LETG 6554, Dinard 35800, France
- LabEX CORAIL, Perpignan, France
| | - Andrew Pomeroy
- ARC Centre of Excellence for Coral Reef Studies, The University of Western Australia, Perth, Western Australia, Australia
- UWA Oceans Institute, The University of Western Australia, Perth, Western Australia, Australia
- Australian Institute of Marine Science, Perth, Western Australia 6009, Australia
| | - Jody M. Webster
- Geocoastal Research Group, School of Geosciences, The University of Sydney, Sydney, New South Wales, Australia
| | - Valeriano Parravicini
- Centre de Recherches Insulaires et Observatoire de l’Environnement, USR 3278 CNRS–École Pratique des Hautes Études (EPHE)–Université de Perpignan Via Domitia, Laboratoire d’Excellence (LabEX) “CORAIL,” University of Perpignan, 66860 Perpignan, France
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22
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Ridge JT, Rodriguez AB, Fodrie FJ. Evidence of exceptional oyster-reef resilience to fluctuations in sea level. Ecol Evol 2017; 7:10409-10420. [PMID: 29238564 PMCID: PMC5723620 DOI: 10.1002/ece3.3473] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 08/18/2017] [Accepted: 09/02/2017] [Indexed: 11/06/2022] Open
Abstract
Ecosystems at the land-sea interface are vulnerable to rising sea level. Intertidal habitats must maintain their surface elevations with respect to sea level to persist via vertical growth or landward retreat, but projected rates of sea-level rise may exceed the accretion rates of many biogenic habitats. While considerable attention is focused on climate change over centennial timescales, relative sea level also fluctuates dramatically (10-30 cm) over month-to-year timescales due to interacting oceanic and atmospheric processes. To assess the response of oyster-reef (Crassostrea virginica) growth to interannual variations in mean sea level (MSL) and improve long-term forecasts of reef response to rising seas, we monitored the morphology of constructed and natural intertidal reefs over 5 years using terrestrial lidar. Timing of reef scans created distinct periods of high and low relative water level for decade-old reefs (n = 3) constructed in 1997 and 2000, young reefs (n = 11) constructed in 2011 and one natural reef (approximately 100 years old). Changes in surface elevation were related to MSL trends. Decade-old reefs achieved 2 cm/year growth, which occurred along higher elevations when MSL increased. Young reefs experienced peak growth (6.7 cm/year) at a lower elevation that coincided with a drop in MSL. The natural reef exhibited considerable loss during the low MSL of the first time step but grew substantially during higher MSL through the second time step, with growth peaking (4.3 cm/year) at MSL, reoccupying the elevations previously lost. Oyster reefs appear to be in dynamic equilibrium with short-term (month-to-year) fluctuations in sea level, evidencing notable resilience to future changes to sea level that surpasses other coastal biogenic habitat types. These growth patterns support the presence of a previously defined optimal growth zone that shifts correspondingly with changes in MSL, which can help guide oyster-reef conservation and restoration.
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Affiliation(s)
- Justin T Ridge
- Institute of Marine Sciences University of North Carolina at Chapel Hill Morehead City NC USA
| | - Antonio B Rodriguez
- Institute of Marine Sciences University of North Carolina at Chapel Hill Morehead City NC USA
| | - F Joel Fodrie
- Institute of Marine Sciences University of North Carolina at Chapel Hill Morehead City NC USA
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23
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Abstract
Strong decreases in greenhouse gas emissions are required to meet the reduction trajectory resolved within the 2015 Paris Agreement. However, even these decreases will not avert serious stress and damage to life on Earth, and additional steps are needed to boost the resilience of ecosystems, safeguard their wildlife, and protect their capacity to supply vital goods and services. We discuss how well-managed marine reserves may help marine ecosystems and people adapt to five prominent impacts of climate change: acidification, sea-level rise, intensification of storms, shifts in species distribution, and decreased productivity and oxygen availability, as well as their cumulative effects. We explore the role of managed ecosystems in mitigating climate change by promoting carbon sequestration and storage and by buffering against uncertainty in management, environmental fluctuations, directional change, and extreme events. We highlight both strengths and limitations and conclude that marine reserves are a viable low-tech, cost-effective adaptation strategy that would yield multiple cobenefits from local to global scales, improving the outlook for the environment and people into the future.
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24
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Allen KA, Bruno JF, Chong F, Clancy D, McClanahan TR, Spencer M, Żychaluk K. Among-site variability in the stochastic dynamics of East African coral reefs. PeerJ 2017; 5:e3290. [PMID: 28533955 PMCID: PMC5437857 DOI: 10.7717/peerj.3290] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 04/10/2017] [Indexed: 11/23/2022] Open
Abstract
Coral reefs are dynamic systems whose composition is highly influenced by unpredictable biotic and abiotic factors. Understanding the spatial scale at which long-term predictions of reef composition can be made will be crucial for guiding conservation efforts. Using a 22-year time series of benthic composition data from 20 reefs on the Kenyan and Tanzanian coast, we developed Bayesian vector autoregressive state-space models for reef dynamics, incorporating among-site variability, and quantified their long-term behaviour. We estimated that if there were no among-site variability, the total long-term variability would be approximately one-third of its current value. Thus, our results showed that among-site variability contributes more to long-term variability in reef composition than does temporal variability. Individual sites were more predictable than previously thought, and predictions based on current snapshots are informative about long-term properties. Our approach allowed us to identify a subset of possible climate refugia sites with high conservation value, where the long-term probability of coral cover ≤0.1 (as a proportion of benthic cover of hard substrate) was very low. Analytical results show that this probability is most strongly influenced by among-site variability and by interactions among benthic components within sites. These findings suggest that conservation initiatives might be successful at the site scale as well as the regional scale.
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Affiliation(s)
- Katherine A Allen
- School of Environmental Sciences, University of Liverpool, Liverpool, United Kingdom.,Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - John F Bruno
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States of America
| | - Fiona Chong
- School of Environmental Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Damian Clancy
- School of Mathematical and Computer Sciences, Actuarial Mathematics and Statistics, Heriot-Watt University, Edinburgh, United Kingdom
| | | | - Matthew Spencer
- School of Environmental Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Kamila Żychaluk
- Department of Mathematical Sciences, University of Liverpool, Liverpool, United Kingdom
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25
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Januchowski-Hartley FA, Graham NAJ, Wilson SK, Jennings S, Perry CT. Drivers and predictions of coral reef carbonate budget trajectories. Proc Biol Sci 2017; 284:20162533. [PMID: 28123092 PMCID: PMC5310043 DOI: 10.1098/rspb.2016.2533] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 01/03/2017] [Indexed: 11/12/2022] Open
Abstract
Climate change is one of the greatest threats to the long-term maintenance of coral-dominated tropical ecosystems, and has received considerable attention over the past two decades. Coral bleaching and associated mortality events, which are predicted to become more frequent and intense, can alter the balance of different elements that are responsible for coral reef growth and maintenance. The geomorphic impacts of coral mass mortality have received relatively little attention, particularly questions concerning temporal recovery of reef carbonate production and the factors that promote resilience of reef growth potential. Here, we track the biological carbonate budgets of inner Seychelles reefs from 1994 to 2014, spanning the 1998 global bleaching event when these reefs lost more than 90% of coral cover. All 21 reefs had positive budgets in 1994, but in 2005 budgets were predominantly negative. By 2014, carbonate budgets on seven reefs were comparable with 1994, but on all reefs where an ecological regime shift to macroalgal dominance occurred, budgets remained negative through 2014. Reefs with higher massive coral cover, lower macroalgae cover and lower excavating parrotfish biomass in 1994 were more likely to have positive budgets post-bleaching. If mortality of corals from the 2016 bleaching event is as severe as that of 1998, our predictions based on past trends would suggest that six of eight reefs with positive budgets in 2014 would still have positive budgets by 2030. Our results highlight that reef accretion and framework maintenance cannot be assumed from the ecological state alone, and that managers should focus on conserving aspects of coral reefs that support resilient carbonate budgets.
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Affiliation(s)
- Fraser A Januchowski-Hartley
- Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
- UMR 248 MARBEC/UMR250 ENTROPIE, UM2-CNRS-IRD-IFREMER-UM1, Université Montpellier 2, Montpellier, France
| | - Nicholas A J Graham
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Queensland 4811, Australia
| | - Shaun K Wilson
- Department of Parks and Wildlife, Kensington, Perth, Western Australia, Australia
- Oceans Institute, University of Western Australia, Crawley, Western Australia, Australia
| | - Simon Jennings
- Centre for Environment, Fisheries and Aquaculture Science, Pakefield Road, Lowestoft NR33 0HT, UK
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Chris T Perry
- Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
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Perry CT, Morgan KM. Bleaching drives collapse in reef carbonate budgets and reef growth potential on southern Maldives reefs. Sci Rep 2017; 7:40581. [PMID: 28084450 PMCID: PMC5233991 DOI: 10.1038/srep40581] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 12/07/2016] [Indexed: 11/26/2022] Open
Abstract
Sea-surface temperature (SST) warming events, which are projected to increase in frequency and intensity with climate change, represent major threats to coral reefs. How these events impact reef carbonate budgets, and thus the capacity of reefs to sustain vertical growth under rising sea levels, remains poorly quantified. Here we quantify the magnitude of changes that followed the ENSO-induced SST warming that affected the Indian Ocean region in mid-2016. Resultant coral bleaching caused an average 75% reduction in coral cover (present mean 6.2%). Most critically we report major declines in shallow fore-reef carbonate budgets, these shifting from strongly net positive (mean 5.92 G, where G = kg CaCO3 m−2 yr−1) to strongly net negative (mean −2.96 G). These changes have driven major reductions in reef growth potential, which have declined from an average 4.2 to −0.4 mm yr−1. Thus these shallow fore-reef habitats are now in a phase of net erosion. Based on past bleaching recovery trajectories, and predicted increases in bleaching frequency, we predict a prolonged period of suppressed budget and reef growth states. This will limit reef capacity to track IPCC projections of sea-level rise, thus limiting the natural breakwater capacity of these reefs and threatening reef island stability.
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Affiliation(s)
- C T Perry
- Department of Geography, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4RJ, United Kingdom
| | - K M Morgan
- Department of Geography, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4RJ, United Kingdom
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