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Miller CA, Gazeau F, Lebrun A, Gattuso JP, Alliouane S, Urrutti P, Schlegel RW, Comeau S. Productivity of mixed kelp communities in an Arctic fjord exhibit tolerance to a future climate. Sci Total Environ 2024; 930:172571. [PMID: 38663592 DOI: 10.1016/j.scitotenv.2024.172571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 03/22/2024] [Accepted: 04/16/2024] [Indexed: 05/02/2024]
Abstract
Arctic fjords are considered to be one of the ecosystems changing most rapidly in response to climate change. In the Svalbard archipelago, fjords are experiencing a shift in environmental conditions due to the Atlantification of Arctic waters and the retreat of sea-terminating glaciers. These environmental changes are predicted to facilitate expansion of large, brown macroalgae, into new ice-free regions. The potential resilience of macroalgal benthic communities in these fjord systems will depend on their response to combined pressures from freshening due to glacial melt, exposure to warmer waters, and increased turbidity from meltwater runoff which reduces light penetration. Current predictions, however, have a limited ability to elucidate the future impacts of multiple-drivers on macroalgal communities with respect to ecosystem function and biogeochemical cycling in Arctic fjords. To assess the impact of these combined future environmental changes on benthic productivity and resilience, we conducted a two-month mesocosm experiment exposing mixed kelp communities to three future conditions comprising increased temperature (+ 3.3 and + 5.3°C), seawater freshening by ∼ 3.0 and ∼ 5.0 units (i.e., salinity of 30 and 28, respectively), and decreased photosynthetically active radiation (PAR, - 25 and - 40 %). Exposure to these combined treatments resulted in non-significant differences in short-term productivity, and a tolerance of the photosynthetic capacity across the treatment conditions. We present the first robust estimates of mixed kelp community production in Kongsfjorden and place a median compensation irradiance of ∼12.5 mmol photons m-2 h-1 as the threshold for positive net community productivity. These results are discussed in the context of ecosystem productivity and biological tolerance of kelp communities in future Arctic fjord systems.
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Affiliation(s)
- Cale A Miller
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, 181 chemin du Lazaret, 06230 Villefranche-sur-Mer, France; Department of Earth Sciences, Geosciences, Utrecht University, Utrecht, the Netherlands.
| | - Frédéric Gazeau
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, 181 chemin du Lazaret, 06230 Villefranche-sur-Mer, France
| | - Anaïs Lebrun
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, 181 chemin du Lazaret, 06230 Villefranche-sur-Mer, France
| | - Jean-Pierre Gattuso
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, 181 chemin du Lazaret, 06230 Villefranche-sur-Mer, France; Institute for Sustainable Development and International Relations, Sciences Po, 27 rue Saint Guillaume, 75007 Paris, France
| | - Samir Alliouane
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, 181 chemin du Lazaret, 06230 Villefranche-sur-Mer, France
| | - Pierre Urrutti
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, 181 chemin du Lazaret, 06230 Villefranche-sur-Mer, France
| | - Robert W Schlegel
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, 181 chemin du Lazaret, 06230 Villefranche-sur-Mer, France
| | - Steeve Comeau
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, 181 chemin du Lazaret, 06230 Villefranche-sur-Mer, France
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2
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Carbonne C, Comeau S, Plichon K, Schaub S, Gattuso JP, Teixidó N. Response of two temperate scleractinian corals to projected ocean warming and marine heatwaves. R Soc Open Sci 2024; 11:231683. [PMID: 38545609 PMCID: PMC10966389 DOI: 10.1098/rsos.231683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Revised: 02/23/2024] [Accepted: 02/26/2024] [Indexed: 04/26/2024]
Abstract
The Mediterranean Sea is a hotspot of global change, particularly exposed to ocean warming and the increasing occurrence of marine heatwaves (MHWs). However, experiments based on long-term temperature data from the field are scarce. Here, we investigate the response of the zooxanthellate coral Cladocora caespitosa and the azooxanthellate coral Astroides calycularis to future warming and MHWs based on 8 years of in situ data. Corals were maintained in the laboratory for five months under four temperature conditions: Warming (3.2°C above the in situ mean from 2012 to 2020), Heatwave (temperatures of 2018 with two heatwaves), Ambient (in situ mean) and Cool (deeper water temperatures). Under the Warming treatment, some C. caespitosa colonies severely bleached and A. calycularis colonies presented necrosis. Cladocora caespitosa symbiosis was impaired by temperature with a decrease in the density of endosymbiotic algae and an increase in per cent whiteness in all the treatments except for the coolest. Recovery for both species was observed through different mechanisms such as regrowth of polyps of A. calycularis and recovery of pigmentation for C. caespitosa. These results suggest that A. calycularis and C. caespitosa may be resilient to heat stress and can recover from physiological stresses caused by heatwaves in the laboratory.
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Affiliation(s)
- Chloe Carbonne
- CNRS, Laboratoire d’Océanographie de Villefranche, Sorbonne Université, 181 chemin du Lazaret, Villefranche-sur-mer, Monaco06230, France
| | - Steeve Comeau
- CNRS, Laboratoire d’Océanographie de Villefranche, Sorbonne Université, 181 chemin du Lazaret, Villefranche-sur-mer, Monaco06230, France
| | - Keyla Plichon
- CNRS, Laboratoire d’Océanographie de Villefranche, Sorbonne Université, 181 chemin du Lazaret, Villefranche-sur-mer, Monaco06230, France
- MSc MARRES, Université Côte d’Azur, Sophia Antipolis Campus, Nice06103, France
| | - Sébastien Schaub
- CNRS, Laboratoire de Biologie du Développement de Villefranche, Sorbonne Université, 181 chemin du Lazaret, Villefranche-sur-mer, Monaco06230, France
| | - Jean-Pierre Gattuso
- CNRS, Laboratoire d’Océanographie de Villefranche, Sorbonne Université, 181 chemin du Lazaret, Villefranche-sur-mer, Monaco06230, France
- Institute for Sustainable Development and International Relations, Sciences Po, 27 rue Saint Guillaume, Paris75007, France
| | - Núria Teixidó
- CNRS, Laboratoire d’Océanographie de Villefranche, Sorbonne Université, 181 chemin du Lazaret, Villefranche-sur-mer, Monaco06230, France
- Department of Integrated Marine Ecology, Stazione Zoologica Anton Dohrn, Ischia Marine Centre, Punta San Pietro, Ischia, Naples80077, Italy
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3
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Cornwall CE, Comeau S, Donner SD, Perry C, Dunne J, van Hooidonk R, Ryan JS, Logan CA. Coral adaptive capacity insufficient to halt global transition of coral reefs into net erosion under climate change. Glob Chang Biol 2023; 29:3010-3018. [PMID: 36943744 DOI: 10.1111/gcb.16647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 02/04/2023] [Accepted: 02/07/2023] [Indexed: 05/03/2023]
Abstract
Projecting the effects of climate change on net reef calcium carbonate production is critical to understanding the future impacts on ecosystem function, but prior estimates have not included corals' natural adaptive capacity to such change. Here we estimate how the ability of symbionts to evolve tolerance to heat stress, or for coral hosts to shuffle to favourable symbionts, and their combination, may influence responses to the combined impacts of ocean warming and acidification under three representative concentration pathway (RCP) emissions scenarios (RCP2.6, RCP4.5 and RCP8.5). We show that symbiont evolution and shuffling, both individually and when combined, favours persistent positive net reef calcium carbonate production. However, our projections of future net calcium carbonate production (NCCP) under climate change vary both spatially and by RCP. For example, 19%-35% of modelled coral reefs are still projected to have net positive NCCP by 2050 if symbionts can evolve increased thermal tolerance, depending on the RCP. Without symbiont adaptive capacity, the number of coral reefs with positive NCCP drops to 9%-13% by 2050. Accounting for both symbiont evolution and shuffling, we project median positive NCPP of coral reefs will still occur under low greenhouse emissions (RCP2.6) in the Indian Ocean, and even under moderate emissions (RCP4.5) in the Pacific Ocean. However, adaptive capacity will be insufficient to halt the transition of coral reefs globally into erosion by 2050 under severe emissions scenarios (RCP8.5).
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Affiliation(s)
- Christopher Edward Cornwall
- School of Biological Sciences and Coastal People Southern Skies, Victoria University of Wellington, Wellington, New Zealand
| | - Steeve Comeau
- Laboratoire d'Océanographie de Villefranche, CNRS-INSU, Sorbonne Université, Villefranche-sur-Mer, France
| | - Simon D Donner
- Institute of Resources, Environment and Sustainability / Department of Geography, University of British Columbia, Vancouver, British Columbia, Canada
| | - Chris Perry
- Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, UK
| | - John Dunne
- NOAA/OAR Geophysical Fluid Dynamics Laboratory, Princeton, New Jersey, USA
| | - Ruben van Hooidonk
- Cooperative Institute for Marine and Atmospheric Studies, Rosenstiel School of Marine and Atmospheric and Earth Science, University of Miami, Miami, Florida, USA
- Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration, Miami, Florida, USA
| | - James S Ryan
- Department of Marine Science, California State University, Monterey Bay, California, USA
| | - Cheryl A Logan
- Department of Marine Science, California State University, Monterey Bay, California, USA
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4
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Schoepf V, Baumann JH, Barshis DJ, Browne NK, Camp EF, Comeau S, Cornwall CE, Guzmán HM, Riegl B, Rodolfo-Metalpa R, Sommer B. Corals at the edge of environmental limits: A new conceptual framework to re-define marginal and extreme coral communities. Sci Total Environ 2023; 884:163688. [PMID: 37105476 DOI: 10.1016/j.scitotenv.2023.163688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 04/14/2023] [Accepted: 04/19/2023] [Indexed: 05/07/2023]
Abstract
The worldwide decline of coral reefs has renewed interest in coral communities at the edge of environmental limits because they have the potential to serve as resilience hotspots and climate change refugia, and can provide insights into how coral reefs might function in future ocean conditions. These coral communities are often referred to as marginal or extreme but few definitions exist and usage of these terms has therefore been inconsistent. This creates significant challenges for categorising these often poorly studied communities and synthesising data across locations. Furthermore, this impedes our understanding of how coral communities can persist at the edge of their environmental limits and the lessons they provide for future coral reef survival. Here, we propose that marginal and extreme coral communities are related but distinct and provide a novel conceptual framework to redefine them. Specifically, we define coral reef extremeness solely based on environmental conditions (i.e., large deviations from optimal conditions in terms of mean and/or variance) and marginality solely based on ecological criteria (i.e., altered community composition and/or ecosystem functioning). This joint but independent assessment of environmental and ecological criteria is critical to avoid common pitfalls where coral communities existing outside the presumed optimal conditions for coral reef development are automatically considered inferior to coral reefs in more traditional settings. We further evaluate the differential potential of marginal and extreme coral communities to serve as natural laboratories, resilience hotspots and climate change refugia, and discuss strategies for their conservation and management as well as priorities for future research. Our new classification framework provides an important tool to improve our understanding of how corals can persist at the edge of their environmental limits and how we can leverage this knowledge to optimise strategies for coral reef conservation, restoration and management in a rapidly changing ocean.
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Affiliation(s)
- Verena Schoepf
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, the Netherlands; UWA Oceans Institute, University of Western Australia, Perth, Western Australia, Australia.
| | - Justin H Baumann
- Department of Biology, Mount Holyoke College, South Hadley, MA, USA
| | - Daniel J Barshis
- Department of Biological Sciences, Old Dominion University, Norfolk, VA, USA
| | - Nicola K Browne
- School of Molecular and Life Sciences, Curtin University, Perth, Western Australia, Australia
| | - Emma F Camp
- Climate Change Cluster, University of Technology Sydney, Sydney, New South Wales, Australia
| | - Steeve Comeau
- Sorbonne Université, CNRS-INSU, Laboratoire d'Océanographie de Villefranche, Villefranche-sur-mer, France
| | - Christopher E Cornwall
- School of Biological Sciences and Coastal People: Southern Skies, Victoria University of Wellington, Wellington, New Zealand
| | - Héctor M Guzmán
- Smithsonian Tropical Research Institute, Panama, Republic of Panama
| | - Bernhard Riegl
- Department of Marine and Environmental Sciences, Halmos College of Arts and Sciences, Nova Southeastern University, Dania Beach, FL, USA
| | - Riccardo Rodolfo-Metalpa
- ENTROPIE, IRD, Université de la Réunion, CNRS, IFREMER, Université de Nouvelle-Calédonie, Nouméa, New Caledonia; Labex ICONA, International CO(2) Natural Analogues Network, Japan
| | - Brigitte Sommer
- School of Life Sciences, University of Technology Sydney, Sydney, New South Wales, Australia; School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, Australia
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5
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Monserrat M, Comeau S, Verdura J, Alliouane S, Spennato G, Priouzeau F, Romero G, Mangialajo L. Climate change and species facilitation affect the recruitment of macroalgal marine forests. Sci Rep 2022; 12:18103. [PMID: 36302874 PMCID: PMC9613703 DOI: 10.1038/s41598-022-22845-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 10/20/2022] [Indexed: 12/30/2022] Open
Abstract
Marine forests are shrinking globally due to several anthropogenic impacts including climate change. Forest-forming macroalgae, such as Cystoseira s.l. species, can be particularly sensitive to environmental conditions (e.g. temperature increase, pollution or sedimentation), especially during early life stages. However, not much is known about their response to the interactive effects of ocean warming (OW) and acidification (OA). These drivers can also affect the performance and survival of crustose coralline algae, which are associated understory species likely playing a role in the recruitment of later successional species such as forest-forming macroalgae. We tested the interactive effects of elevated temperature, low pH and species facilitation on the recruitment of Cystoseira compressa. We demonstrate that the interactive effects of OW and OA negatively affect the recruitment of C. compressa and its associated coralline algae Neogoniolithon brassica-florida. The density of recruits was lower under the combinations OW and OA, while the size was negatively affected by the temperature increase but positively affected by the low pH. The results from this study show that the interactive effects of climate change and the presence of crustose coralline algae can have a negative impact on the recruitment of Cystoseira s.l. species. While new restoration techniques recently opened the door to marine forest restoration, our results show that the interactions of multiple drivers and species interactions have to be considered to achieve long-term population sustainability.
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Affiliation(s)
- Margalida Monserrat
- grid.4444.00000 0001 2112 9282Université Côte d’Azur, CNRS, ECOSEAS, Nice, France ,grid.4444.00000 0001 2112 9282Sorbonne Université, CNRS, Laboratoire d’Océanographie de Villefranche, Villefranche-sur-Mer, France
| | - Steeve Comeau
- grid.4444.00000 0001 2112 9282Sorbonne Université, CNRS, Laboratoire d’Océanographie de Villefranche, Villefranche-sur-Mer, France
| | - Jana Verdura
- grid.4444.00000 0001 2112 9282Université Côte d’Azur, CNRS, ECOSEAS, Nice, France
| | - Samir Alliouane
- grid.4444.00000 0001 2112 9282Sorbonne Université, CNRS, Laboratoire d’Océanographie de Villefranche, Villefranche-sur-Mer, France
| | - Guillaume Spennato
- grid.4444.00000 0001 2112 9282Université Côte d’Azur, CNRS, ECOSEAS, Nice, France
| | - Fabrice Priouzeau
- grid.4444.00000 0001 2112 9282Université Côte d’Azur, CNRS, ECOSEAS, Nice, France
| | - Gilbers Romero
- grid.4444.00000 0001 2112 9282Université Côte d’Azur, CNRS, ECOSEAS, Nice, France
| | - Luisa Mangialajo
- grid.4444.00000 0001 2112 9282Université Côte d’Azur, CNRS, ECOSEAS, Nice, France
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6
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Garrabou J, Gómez‐Gras D, Medrano A, Cerrano C, Ponti M, Schlegel R, Bensoussan N, Turicchia E, Sini M, Gerovasileiou V, Teixido N, Mirasole A, Tamburello L, Cebrian E, Rilov G, Ledoux J, Souissi JB, Khamassi F, Ghanem R, Benabdi M, Grimes S, Ocaña O, Bazairi H, Hereu B, Linares C, Kersting DK, la Rovira G, Ortega J, Casals D, Pagès‐Escolà M, Margarit N, Capdevila P, Verdura J, Ramos A, Izquierdo A, Barbera C, Rubio‐Portillo E, Anton I, López‐Sendino P, Díaz D, Vázquez‐Luis M, Duarte C, Marbà N, Aspillaga E, Espinosa F, Grech D, Guala I, Azzurro E, Farina S, Cristina Gambi M, Chimienti G, Montefalcone M, Azzola A, Mantas TP, Fraschetti S, Ceccherelli G, Kipson S, Bakran‐Petricioli T, Petricioli D, Jimenez C, Katsanevakis S, Kizilkaya IT, Kizilkaya Z, Sartoretto S, Elodie R, Ruitton S, Comeau S, Gattuso J, Harmelin J. Marine heatwaves drive recurrent mass mortalities in the Mediterranean Sea. Glob Chang Biol 2022; 28:5708-5725. [PMID: 35848527 PMCID: PMC9543131 DOI: 10.1111/gcb.16301] [Citation(s) in RCA: 55] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 05/10/2022] [Accepted: 05/15/2022] [Indexed: 05/12/2023]
Abstract
Climate change is causing an increase in the frequency and intensity of marine heatwaves (MHWs) and mass mortality events (MMEs) of marine organisms are one of their main ecological impacts. Here, we show that during the 2015-2019 period, the Mediterranean Sea has experienced exceptional thermal conditions resulting in the onset of five consecutive years of widespread MMEs across the basin. These MMEs affected thousands of kilometers of coastline from the surface to 45 m, across a range of marine habitats and taxa (50 taxa across 8 phyla). Significant relationships were found between the incidence of MMEs and the heat exposure associated with MHWs observed both at the surface and across depths. Our findings reveal that the Mediterranean Sea is experiencing an acceleration of the ecological impacts of MHWs which poses an unprecedented threat to its ecosystems' health and functioning. Overall, we show that increasing the resolution of empirical observation is critical to enhancing our ability to more effectively understand and manage the consequences of climate change.
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Affiliation(s)
- Joaquim Garrabou
- Institut de Ciències del Mar‐CSICBarcelonaSpain
- Université de Toulon, CNRS, IRD, MIOAix Marseille UnivMarseilleFrance
| | - Daniel Gómez‐Gras
- Institut de Ciències del Mar‐CSICBarcelonaSpain
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia, Institut de Recerca de la Biodiversitat (IRBIO)Universitat de BarcelonaBarcelonaSpain
| | - Alba Medrano
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia, Institut de Recerca de la Biodiversitat (IRBIO)Universitat de BarcelonaBarcelonaSpain
| | - Carlo Cerrano
- Dept of Life and Environmental SciencesPolytechnic University of MarcheAnconaItaly
- Fano Marine CentreFanoItaly
| | - Massimo Ponti
- Department of Biological, Geological and Environmental SciencesUniversity of BolognaRavennaItaly
- CoNISMaRomeItaly
| | - Robert Schlegel
- Laboratoire d'Océanographie de VillefrancheSorbonne, Université, CNRSVillefranche‐sur‐merFrance
| | - Nathaniel Bensoussan
- Institut de Ciències del Mar‐CSICBarcelonaSpain
- Université de Toulon, CNRS, IRD, MIOAix Marseille UnivMarseilleFrance
| | - Eva Turicchia
- Department of Biological, Geological and Environmental SciencesUniversity of BolognaRavennaItaly
- CoNISMaRomeItaly
| | - Maria Sini
- Department of Marine SciencesUniversity of the AegeanMytileneGreece
| | - Vasilis Gerovasileiou
- Department of Environment, Faculty of EnvironmentIonian UniversityZakynthosGreece
- Hellenic Centre for Marine Research (HCMR)Institute of Marine Biology, Biotechnology and Aquaculture (IMBBC)HeraklionGreece
| | - Nuria Teixido
- Laboratoire d'Océanographie de VillefrancheSorbonne, Université, CNRSVillefranche‐sur‐merFrance
- Stazione Zoologica Anton Dohrn, Department of Integrative Marine EcologyIschia Marine CentreNaplesItaly
| | - Alice Mirasole
- Stazione Zoologica Anton Dohrn, Department of Integrative Marine EcologyIschia Marine CentreNaplesItaly
| | - Laura Tamburello
- Stazione Zoologica Anton Dohrn, Department of Integrative Marine EcologyIschia Marine CentreNaplesItaly
| | - Emma Cebrian
- Centre d'Estudis Avançats de Blanes (CEAB‐CSIC)GironaSpain
| | - Gil Rilov
- National Institute of OceanographyIsrael Oceanographic and Limnological Research (IOLR)HaifaIsrael
| | - Jean‐Baptiste Ledoux
- Institut de Ciències del Mar‐CSICBarcelonaSpain
- CIIMAR‐Interdisciplinary Centre of Marine and Environmental ResearchUniversity of PortoMatosinhosPortugal
| | - Jamila Ben Souissi
- National Agronomic Institute of TunisiaTunis University of CarthageTunisTunisia
- Biodiversity, Biotechnology and Climate Change Laboratory‐LR11ES09University of Tunis El ManarTunisTunisia
| | - Faten Khamassi
- National Agronomic Institute of TunisiaTunis University of CarthageTunisTunisia
| | - Raouia Ghanem
- Biodiversity, Biotechnology and Climate Change Laboratory‐LR11ES09University of Tunis El ManarTunisTunisia
| | | | - Samir Grimes
- Ecole Nationale Supérieure des Sciences de la Mer et de l'Aménagement (ENSSMAL)AlgerAlgeria
| | | | - Hocein Bazairi
- Laboratory 'Biodiversity, Ecology and Genome', Faculty of SciencesMohamed V University in RabatRabatMorocco
| | - Bernat Hereu
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia, Institut de Recerca de la Biodiversitat (IRBIO)Universitat de BarcelonaBarcelonaSpain
| | - Cristina Linares
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia, Institut de Recerca de la Biodiversitat (IRBIO)Universitat de BarcelonaBarcelonaSpain
| | - Diego Kurt Kersting
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia, Institut de Recerca de la Biodiversitat (IRBIO)Universitat de BarcelonaBarcelonaSpain
| | - Graciel la Rovira
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia, Institut de Recerca de la Biodiversitat (IRBIO)Universitat de BarcelonaBarcelonaSpain
| | - Júlia Ortega
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia, Institut de Recerca de la Biodiversitat (IRBIO)Universitat de BarcelonaBarcelonaSpain
| | - David Casals
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia, Institut de Recerca de la Biodiversitat (IRBIO)Universitat de BarcelonaBarcelonaSpain
| | - Marta Pagès‐Escolà
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia, Institut de Recerca de la Biodiversitat (IRBIO)Universitat de BarcelonaBarcelonaSpain
| | - Núria Margarit
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia, Institut de Recerca de la Biodiversitat (IRBIO)Universitat de BarcelonaBarcelonaSpain
| | - Pol Capdevila
- School of Biological SciencesUniversity of BristolBristolUK
| | | | - Alfonso Ramos
- Departamento de Ciencias del Mar y Biología AplicadaUniversidad de AlicanteAlicanteSpain
| | | | - Carmen Barbera
- Departamento de Ciencias del Mar y Biología AplicadaUniversidad de AlicanteAlicanteSpain
| | | | | | | | - David Díaz
- Centro Oceanográfico de Baleares (IEO‐CSIC)Palma de MallorcaSpain
| | | | - Carlos Duarte
- Red Sea Research CenterKing Abudllah University of Science and TechnologyThuwalSaudi Arabia
- Institut Mediterrani d'Estudis AvançatsMallorcaSpain
| | - Nuria Marbà
- Institut Mediterrani d'Estudis AvançatsMallorcaSpain
| | | | - Free Espinosa
- Laboratorio de Biología MarinaUniversidad de SevillaSevillaSpain
| | | | - Ivan Guala
- IMC—International Marine CentreOristanoItaly
| | - Ernesto Azzurro
- Stazione Zoologica Anton Dohrn, Department of Integrative Marine EcologyIschia Marine CentreNaplesItaly
- CNR‐IRBIM, NR‐IRBIM, National Research CouncilInstitute of Biological Resources and Marine BiotechnologiesAnconaItaly
| | - Simone Farina
- Stazione Zoologica Anton Dohrn, Deptartment of Integrative Marine EcologyGenoa Marine CentreGenoaItaly
| | | | - Giovanni Chimienti
- CoNISMaRomeItaly
- Department of BiologyUniversity of Bari Aldo MoroBariItaly
| | - Monica Montefalcone
- Department of Earth, Environment and Life SciencesUniversity of GenoaGenoaItaly
| | - Annalisa Azzola
- Department of Earth, Environment and Life SciencesUniversity of GenoaGenoaItaly
| | | | - Simonetta Fraschetti
- CoNISMaRomeItaly
- Department of BiologyUniversity of Naples Federico IINaplesItaly
| | | | - Silvija Kipson
- SEAFANZagrebCroatia
- Faculty of Science, Department of BiologyUniversity of ZagrebZagrebCroatia
| | | | - Donat Petricioli
- D.I.I.V. Ltd for Marine, Freshwater and Subterranean EcologySaliCroatia
| | - Carlos Jimenez
- Enalia Physis Environmental Research CentreNicosiaCyprus
- The Cyprus Institute Energy Environment and Water Research CenterAglantziaCyprus
| | | | | | | | | | | | - Sandrine Ruitton
- Université de Toulon, CNRS, IRD, MIOAix Marseille UnivMarseilleFrance
| | - Steeve Comeau
- Laboratoire d'Océanographie de VillefrancheSorbonne, Université, CNRSVillefranche‐sur‐merFrance
| | - Jean‐Pierre Gattuso
- Laboratoire d'Océanographie de VillefrancheSorbonne, Université, CNRSVillefranche‐sur‐merFrance
- Institute for Sustainable Development and International Relations. Sciences PoParisFrance
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7
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Comeau S, Cornwall CE, Shlesinger T, Hoogenboom M, Mana R, McCulloch MT, Rodolfo-Metalpa R. pH variability at volcanic CO 2 seeps regulates coral calcifying fluid chemistry. Glob Chang Biol 2022; 28:2751-2763. [PMID: 35119159 DOI: 10.1111/gcb.16093] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Revised: 12/17/2021] [Accepted: 12/20/2021] [Indexed: 06/14/2023]
Abstract
Coral reefs are iconic ecosystems with immense ecological, economic and cultural value, but globally their carbonate-based skeletal construction is threatened by ocean acidification (OA). Identifying coral species that have specialised mechanisms to maintain high rates of calcification in the face of declining seawater pH is of paramount importance in predicting future species composition, and growth of coral reefs. Here, we studied multiple coral species from two distinct volcanic CO2 seeps in Papua New Guinea to assess their capacity to control their calcifying fluid (CF) chemistry. Several coral species living under conditions of low mean seawater pH, but with either low or high variability in seawater pH, were examined and compared with those living in 'normal' (non-seep) ambient seawater pH. We show that when mean seawater pH is low but highly variable, corals have a greater ability to maintain constant pHcf in their CF, but this characteristic was not linked with changes in abundance. Within less variable low pH seawater, corals with limited reductions in pHcf at the seep sites compared with controls tended to be more abundant at the seep site than at the control site. However, this finding was strongly influenced by a single species (Montipora foliosa), which was able to maintain complete pHcf homeostasis. Overall, although our findings indicate that there might be an association between ecological success and greater pHcf homeostasis, further research with additional species and at more sites with differing seawater pH regimes is required to solidify inferences regarding coral ecological success under future OA.
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Affiliation(s)
- Steeve Comeau
- CNRS-INSU, Laboratoire d'Océanographie de Villefranche, Sorbonne Université, Villefranche- sur-mer, France
- ARC Centre of Excellence for Coral Reef Studies and Ocean Graduate School, The University of Western Australia, Crawley, Western Australia, Australia
| | - Christopher E Cornwall
- ARC Centre of Excellence for Coral Reef Studies and Ocean Graduate School, The University of Western Australia, Crawley, Western Australia, Australia
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Tom Shlesinger
- Institute for Global Ecology, Florida Institute of Technology, Melbourne, Florida, USA
| | - Mia Hoogenboom
- ARC Centre of Excellence for Coral Reef Studies and College of Science and Engineering, James Cook University, Townsville, Queensland, Australia
| | - Ralph Mana
- School of Natural and Physical Sciences, University of Papua New Guinea, Port Moresby, National Capital District, Papua New Guinea
| | - Malcolm T McCulloch
- ARC Centre of Excellence for Coral Reef Studies and Ocean Graduate School, The University of Western Australia, Crawley, Western Australia, Australia
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8
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Cornwall CE, Harvey BP, Comeau S, Cornwall DL, Hall-Spencer JM, Peña V, Wada S, Porzio L. Understanding coralline algal responses to ocean acidification: Meta-analysis and synthesis. Glob Chang Biol 2022; 28:362-374. [PMID: 34689395 DOI: 10.1111/gcb.15899] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 09/15/2021] [Accepted: 09/16/2021] [Indexed: 06/13/2023]
Abstract
Ocean acidification (OA) is a major threat to the persistence of biogenic reefs throughout the world's ocean. Coralline algae are comprised of high magnesium calcite and have long been considered one of the most susceptible taxa to the negative impacts of OA. We summarize these impacts and explore the causes of variability in coralline algal responses using a review/qualitative assessment of all relevant literature, meta-analysis, quantitative assessment of critical responses, and a discussion of physiological mechanisms and directions for future research. We find that most coralline algae experienced reduced abundance, calcification rates, recruitment rates, and declines in pH within the site of calcification in laboratory experiments simulating OA or at naturally elevated CO2 sites. There were no other consistent physiological responses of coralline algae to simulated OA (e.g., photo-physiology, mineralogy, and survival). Calcification/growth was the most frequently measured parameters in coralline algal OA research, and our meta-analyses revealed greater declines in seawater pH were associated with significant decreases in calcification in adults and similar but nonsignificant trends for juveniles. Adults from the family Mesophyllumaceae also tended to be more robust to OA, though there was insufficient data to test similar trends for juveniles. OA was the dominant driver in the majority of laboratory experiments where other local or global drivers were assessed. The interaction between OA and any other single driver was often additive, though factors that changed pH at the surface of coralline algae (light, water motion, epiphytes) acted antagonistically or synergistically with OA more than any other drivers. With advances in experimental design and methodological techniques, we now understand that the physiology of coralline algal calcification largely dictates their responses to OA. However, significant challenges still remain, including improving the geographic and life-history spread of research effort and a need for holistic assessments of physiology.
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Affiliation(s)
- Christopher E Cornwall
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Ben P Harvey
- Shimoda Marine Research Center, University of Tsukuba, Shimoda, Shizuoka, Japan
| | - Steeve Comeau
- Laboratoire d'Océanographie de Villefranche, Sorbonne Université, CNRS-INSU, Villefranche-sur-mer, France
| | - Daniel L Cornwall
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Jason M Hall-Spencer
- Shimoda Marine Research Center, University of Tsukuba, Shimoda, Shizuoka, Japan
- School of Biological and Marine Sciences, University of Plymouth, Plymouth, UK
| | - Viviana Peña
- BioCost Research Group, Facultad de Ciencias, Universidade da Coruña, Coruña, Spain
| | - Shigeki Wada
- Shimoda Marine Research Center, University of Tsukuba, Shimoda, Shizuoka, Japan
| | - Lucia Porzio
- Shimoda Marine Research Center, University of Tsukuba, Shimoda, Shizuoka, Japan
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9
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Cornwall CE, Comeau S, Kornder NA, Perry CT, van Hooidonk R, DeCarlo TM, Pratchett MS, Anderson KD, Browne N, Carpenter R, Diaz-Pulido G, D'Olivo JP, Doo SS, Figueiredo J, Fortunato SAV, Kennedy E, Lantz CA, McCulloch MT, González-Rivero M, Schoepf V, Smithers SG, Lowe RJ. Global declines in coral reef calcium carbonate production under ocean acidification and warming. Proc Natl Acad Sci U S A 2021; 118:e2015265118. [PMID: 33972407 PMCID: PMC8166140 DOI: 10.1073/pnas.2015265118] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Ocean warming and acidification threaten the future growth of coral reefs. This is because the calcifying coral reef taxa that construct the calcium carbonate frameworks and cement the reef together are highly sensitive to ocean warming and acidification. However, the global-scale effects of ocean warming and acidification on rates of coral reef net carbonate production remain poorly constrained despite a wealth of studies assessing their effects on the calcification of individual organisms. Here, we present global estimates of projected future changes in coral reef net carbonate production under ocean warming and acidification. We apply a meta-analysis of responses of coral reef taxa calcification and bioerosion rates to predicted changes in coral cover driven by climate change to estimate the net carbonate production rates of 183 reefs worldwide by 2050 and 2100. We forecast mean global reef net carbonate production under representative concentration pathways (RCP) 2.6, 4.5, and 8.5 will decline by 76, 149, and 156%, respectively, by 2100. While 63% of reefs are projected to continue to accrete by 2100 under RCP2.6, 94% will be eroding by 2050 under RCP8.5, and no reefs will continue to accrete at rates matching projected sea level rise under RCP4.5 or 8.5 by 2100. Projected reduced coral cover due to bleaching events predominately drives these declines rather than the direct physiological impacts of ocean warming and acidification on calcification or bioerosion. Presently degraded reefs were also more sensitive in our analysis. These findings highlight the low likelihood that the world's coral reefs will maintain their functional roles without near-term stabilization of atmospheric CO2 emissions.
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Affiliation(s)
- Christopher E Cornwall
- School of Biological Sciences, Victoria University of Wellington, Kelburn 6140, Wellington, New Zealand;
- Oceans Graduate School and Oceans Institute, The University of Western Australia, Crawley 6009, WA, Australia
- Australian Research Council Centre of Excellence for Coral Reef Studies, Crawley 6009, WA, Australia
| | - Steeve Comeau
- Oceans Graduate School and Oceans Institute, The University of Western Australia, Crawley 6009, WA, Australia
- Australian Research Council Centre of Excellence for Coral Reef Studies, Crawley 6009, WA, Australia
- Laboratoire d'Océanographie de Villefranche, French National Centre for Scientific Research National Institute for Earth Sciences and Astronomy, Sorbonne Université, F-06230 Villefranche-sur-mer, France
| | - Niklas A Kornder
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, 1090 GE, Amsterdam, The Netherlands
- Halmos College of Arts and Sciences, Nova Southeastern University, Nova Southeastern University, Dania Beach, FL 33004
| | - Chris T Perry
- Geography, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4RJ, United Kingdom
| | - Ruben van Hooidonk
- Cooperative Institute for Marine and Atmospheric Studies, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL 33149
- Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration, Miami, FL 33149
| | - Thomas M DeCarlo
- Oceans Graduate School and Oceans Institute, The University of Western Australia, Crawley 6009, WA, Australia
- Australian Research Council Centre of Excellence for Coral Reef Studies, Crawley 6009, WA, Australia
- College of Natural and Computational Sciences, Hawai'i Pacific University, Honolulu, HI 96813
| | - Morgan S Pratchett
- Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia
| | - Kristen D Anderson
- Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia
| | - Nicola Browne
- School of Molecular and Life Sciences, Curtin University, Bentley, WA 6102, Australia
| | - Robert Carpenter
- Department of Biology, California State University, Northridge, CA 91330
| | - Guillermo Diaz-Pulido
- School of Environment and Science and Australian Rivers Institute, Griffith University, Brisbane, QLD 4111, Australia
| | - Juan P D'Olivo
- Oceans Graduate School and Oceans Institute, The University of Western Australia, Crawley 6009, WA, Australia
- Australian Research Council Centre of Excellence for Coral Reef Studies, Crawley 6009, WA, Australia
| | - Steve S Doo
- Department of Biology, California State University, Northridge, CA 91330
- Geoecology and Carbonate Sedimentology Group, Leibniz Centre for Tropical Marine Research (ZMT), 28359 Bremen, Germany
| | - Joana Figueiredo
- Halmos College of Arts and Sciences, Nova Southeastern University, Nova Southeastern University, Dania Beach, FL 33004
| | - Sofia A V Fortunato
- College of Science and Engineering, James Cook University, QLD 4811, Australia
| | - Emma Kennedy
- School of Environment and Science and Australian Rivers Institute, Griffith University, Brisbane, QLD 4111, Australia
- Global Change Institute, University of Queensland, Brisbane, QLD 4072, Australia
| | - Coulson A Lantz
- Centre for Coastal Biogeochemistry, School of Environment, Science, and Engineering, Southern Cross University, Lismore, NSW 2480, Australia
- School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia
| | - Malcolm T McCulloch
- Oceans Graduate School and Oceans Institute, The University of Western Australia, Crawley 6009, WA, Australia
- Australian Research Council Centre of Excellence for Coral Reef Studies, Crawley 6009, WA, Australia
| | - Manuel González-Rivero
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia
- Global Change Institute, University of Queensland, Brisbane, QLD 4072, Australia
| | - Verena Schoepf
- Oceans Graduate School and Oceans Institute, The University of Western Australia, Crawley 6009, WA, Australia
- Australian Research Council Centre of Excellence for Coral Reef Studies, Crawley 6009, WA, Australia
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, 1090 GE, Amsterdam, The Netherlands
| | - Scott G Smithers
- College of Science and Engineering, James Cook University, QLD 4811, Australia
| | - Ryan J Lowe
- Oceans Graduate School and Oceans Institute, The University of Western Australia, Crawley 6009, WA, Australia
- Australian Research Council Centre of Excellence for Coral Reef Studies, Crawley 6009, WA, Australia
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10
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Moore B, Comeau S, Bekaert M, Cossais A, Purdy A, Larcombe E, Puerzer F, McCulloch MT, Cornwall CE. Rapid multi-generational acclimation of coralline algal reproductive structures to ocean acidification. Proc Biol Sci 2021; 288:20210130. [PMID: 33975470 PMCID: PMC8113899 DOI: 10.1098/rspb.2021.0130] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 04/15/2021] [Indexed: 12/25/2022] Open
Abstract
The future of coral reef ecosystems is under threat because vital reef-accreting species such as coralline algae are highly susceptible to ocean acidification. Although ocean acidification is known to reduce coralline algal growth rates, its direct effects on the development of coralline algal reproductive structures (conceptacles) is largely unknown. Furthermore, the long-term, multi-generational response of coralline algae to ocean acidification is extremely understudied. Here, we investigate how mean pH, pH variability and the pH regime experienced in their natural habitat affect coralline algal conceptacle abundance and size across six generations of exposure. We show that second-generation coralline algae exposed to ocean acidification treatments had conceptacle abundances 60% lower than those kept in present-day conditions, suggesting that conceptacle development is initially highly sensitive to ocean acidification. However, this negative effect of ocean acidification on conceptacle abundance disappears after three generations of exposure. Moreover, we show that this transgenerational acclimation of conceptacle development is not facilitated by a trade-off with reduced investment in growth, as higher conceptacle abundances are associated with crusts with faster growth rates. These results indicate that the potential reproductive output of coralline algae may be sustained under future ocean acidification.
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Affiliation(s)
- B. Moore
- Marine Climate Change Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
- ARC Centre of Excellence for Coral Reef Studies, The University of Western Australia, Crawley, Western Australia, Australia
| | - S. Comeau
- ARC Centre of Excellence for Coral Reef Studies, The University of Western Australia, Crawley, Western Australia, Australia
- Sorbonne Université, CNRS-INSU, Laboratoire d'Océanographie de Villefranche, Villefranche-sur-mer, France
| | - M. Bekaert
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - A. Cossais
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - A. Purdy
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - E. Larcombe
- ARC Centre of Excellence for Coral Reef Studies, The University of Western Australia, Crawley, Western Australia, Australia
| | - F. Puerzer
- ARC Centre of Excellence for Coral Reef Studies, The University of Western Australia, Crawley, Western Australia, Australia
| | - M. T. McCulloch
- ARC Centre of Excellence for Coral Reef Studies, The University of Western Australia, Crawley, Western Australia, Australia
| | - C. E. Cornwall
- ARC Centre of Excellence for Coral Reef Studies, The University of Western Australia, Crawley, Western Australia, Australia
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
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11
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Teixidó N, Caroselli E, Alliouane S, Ceccarelli C, Comeau S, Gattuso JP, Fici P, Micheli F, Mirasole A, Monismith SG, Munari M, Palumbi SR, Sheets E, Urbini L, De Vittor C, Goffredo S, Gambi MC. Ocean acidification causes variable trait-shifts in a coral species. Glob Chang Biol 2020; 26:6813-6830. [PMID: 33002274 DOI: 10.1111/gcb.15372] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 09/12/2020] [Accepted: 09/14/2020] [Indexed: 06/11/2023]
Abstract
High pCO2 habitats and their populations provide an unparalleled opportunity to assess how species may survive under future ocean acidification conditions, and help to reveal the traits that confer tolerance. Here we utilize a unique CO2 vent system to study the effects of exposure to elevated pCO2 on trait-shifts observed throughout natural populations of Astroides calycularis, an azooxanthellate scleractinian coral endemic to the Mediterranean. Unexpected shifts in skeletal and growth patterns were found. Colonies shifted to a skeletal phenotype characterized by encrusting morphology, smaller size, reduced coenosarc tissue, fewer polyps, and less porous and denser skeletons at low pH. Interestingly, while individual polyps calcified more and extended faster at low pH, whole colonies found at low pH site calcified and extended their skeleton at the same rate as did those at ambient pH sites. Transcriptomic data revealed strong genetic differentiation among local populations of this warm water species whose distribution range is currently expanding northward. We found excess differentiation in the CO2 vent population for genes central to calcification, including genes for calcium management (calmodulin, calcium-binding proteins), pH regulation (V-type proton ATPase), and inorganic carbon regulation (carbonic anhydrase). Combined, our results demonstrate how coral populations can persist in high pCO2 environments, making this system a powerful candidate for investigating acclimatization and local adaptation of organisms to global environmental change.
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Affiliation(s)
- Núria Teixidó
- Stazione Zoologica Anton Dohrn, Deptartment of Integrative Marine Ecology, Ischia Marine Centre, Naples, Italy
- Laboratoire d'Océanographie de Villefranche, CNRS, Sorbonne Université, Villefranche-sur-mer, France
| | - Erik Caroselli
- Marine Science Group, Department of Biological, Geological, and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Samir Alliouane
- Laboratoire d'Océanographie de Villefranche, CNRS, Sorbonne Université, Villefranche-sur-mer, France
| | - Chiara Ceccarelli
- Marine Science Group, Department of Biological, Geological, and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Steeve Comeau
- Laboratoire d'Océanographie de Villefranche, CNRS, Sorbonne Université, Villefranche-sur-mer, France
| | - Jean-Pierre Gattuso
- Laboratoire d'Océanographie de Villefranche, CNRS, Sorbonne Université, Villefranche-sur-mer, France
- Institute for Sustainable Development and International Relations, Paris, France
| | - Pietro Fici
- Marine Science Group, Department of Biological, Geological, and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Fiorenza Micheli
- Department of Biology, Hopkins Marine Station, Stanford University, Pacific Grove, CA, USA
- Stanford Center for Ocean Solutions, Pacific Grove, CA, USA
| | - Alice Mirasole
- Stazione Zoologica Anton Dohrn, Deptartment of Integrative Marine Ecology, Ischia Marine Centre, Naples, Italy
| | - Stephen G Monismith
- Department of Civil and Environmental Engineering, Stanford University, Stanford, CA, USA
| | - Marco Munari
- Stazione Zoologica Anton Dohrn, Deptartment of Integrative Marine Ecology, Ischia Marine Centre, Naples, Italy
| | - Stephen R Palumbi
- Department of Biology, Hopkins Marine Station, Stanford University, Pacific Grove, CA, USA
| | - Elizabeth Sheets
- Department of Biology, Hopkins Marine Station, Stanford University, Pacific Grove, CA, USA
| | - Lidia Urbini
- National Institute of Oceanography and Applied Geophysics - OGS, Trieste, Italy
| | - Cinzia De Vittor
- National Institute of Oceanography and Applied Geophysics - OGS, Trieste, Italy
| | - Stefano Goffredo
- Marine Science Group, Department of Biological, Geological, and Environmental Sciences, University of Bologna, Bologna, Italy
- Fano Marine Center, The Inter-Institute Center for Research on Marine Biodiversity, Resources and Biotechnologies, Fano, Italy
| | - Maria Cristina Gambi
- Stazione Zoologica Anton Dohrn, Deptartment of Integrative Marine Ecology, Ischia Marine Centre, Naples, Italy
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12
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DeCarlo TM, Comeau S, Cornwall CE, Gajdzik L, Guagliardo P, Sadekov A, Thillainath EC, Trotter J, McCulloch MT. Investigating marine bio-calcification mechanisms in a changing ocean with in vivo and high-resolution ex vivo Raman spectroscopy. Glob Chang Biol 2019; 25:1877-1888. [PMID: 30689259 PMCID: PMC6916197 DOI: 10.1111/gcb.14579] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 01/20/2019] [Accepted: 01/21/2019] [Indexed: 05/20/2023]
Abstract
Ocean acidification poses a serious threat to marine calcifying organisms, yet experimental and field studies have found highly diverse responses among species and environments. Our understanding of the underlying drivers of differential responses to ocean acidification is currently limited by difficulties in directly observing and quantifying the mechanisms of bio-calcification. Here, we present Raman spectroscopy techniques for characterizing the skeletal mineralogy and calcifying fluid chemistry of marine calcifying organisms such as corals, coralline algae, foraminifera, and fish (carbonate otoliths). First, our in vivo Raman technique is the ideal tool for investigating non-classical mineralization pathways. This includes calcification by amorphous particle attachment, which has recently been controversially suggested as a mechanism by which corals resist the negative effects of ocean acidification. Second, high-resolution ex vivo Raman mapping reveals complex banding structures in the mineralogy of marine calcifiers, and provides a tool to quantify calcification responses to environmental variability on various timescales from days to years. We describe the new insights into marine bio-calcification that our techniques have already uncovered, and we consider the wide range of questions regarding calcifier responses to global change that can now be proposed and addressed with these new Raman spectroscopy tools.
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Affiliation(s)
- Thomas M. DeCarlo
- Oceans Graduate SchoolThe University of Western AustraliaCrawleyWestern AustraliaAustralia
- Oceans Institute at The University of Western AustraliaCrawleyWestern AustraliaAustralia
- ARC Centre of Excellence for Coral Reef StudiesCrawleyWestern AustraliaAustralia
| | - Steeve Comeau
- Oceans Graduate SchoolThe University of Western AustraliaCrawleyWestern AustraliaAustralia
- Oceans Institute at The University of Western AustraliaCrawleyWestern AustraliaAustralia
- ARC Centre of Excellence for Coral Reef StudiesCrawleyWestern AustraliaAustralia
- Present address:
Sorbonne Université, CNRS‐INSU, Laboratoire d'Océanographie de 30 Villefranche181 chemin du Lazaret, F–06230 Villefranche‐sur‐merFrance
| | - Christopher E. Cornwall
- Oceans Graduate SchoolThe University of Western AustraliaCrawleyWestern AustraliaAustralia
- Oceans Institute at The University of Western AustraliaCrawleyWestern AustraliaAustralia
- ARC Centre of Excellence for Coral Reef StudiesCrawleyWestern AustraliaAustralia
- Present address:
School of Biological SciencesVictoria University of WellingtonWellingtonNew‐Zealand
| | - Laura Gajdzik
- School of Molecular and Life Sciences, TrEnD LaboratoryCurtin UniversityBentleyWestern AustraliaAustralia
| | - Paul Guagliardo
- Centre for Microscopy, Characterisation and AnalysisThe University of Western AustraliaCrawleyWestern AustraliaAustralia
| | - Aleksey Sadekov
- Oceans Graduate SchoolThe University of Western AustraliaCrawleyWestern AustraliaAustralia
- Oceans Institute at The University of Western AustraliaCrawleyWestern AustraliaAustralia
- ARC Centre of Excellence for Coral Reef StudiesCrawleyWestern AustraliaAustralia
| | - Emma C. Thillainath
- Oceans Institute at The University of Western AustraliaCrawleyWestern AustraliaAustralia
- School of Biological SciencesThe University of Western AustraliaCrawleyWestern AustraliaAustralia
| | - Julie Trotter
- Oceans Institute at The University of Western AustraliaCrawleyWestern AustraliaAustralia
- School of Earth SciencesThe University of Western AustraliaCrawleyWestern AustraliaAustralia
| | - Malcolm T. McCulloch
- Oceans Graduate SchoolThe University of Western AustraliaCrawleyWestern AustraliaAustralia
- Oceans Institute at The University of Western AustraliaCrawleyWestern AustraliaAustralia
- ARC Centre of Excellence for Coral Reef StudiesCrawleyWestern AustraliaAustralia
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13
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DeCarlo TM, Comeau S, Cornwall CE, McCulloch MT. Coral resistance to ocean acidification linked to increased calcium at the site of calcification. Proc Biol Sci 2019; 285:rspb.2018.0564. [PMID: 29720418 DOI: 10.1098/rspb.2018.0564] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 04/09/2018] [Indexed: 11/12/2022] Open
Abstract
Ocean acidification threatens the persistence of biogenic calcium carbonate (CaCO3) production on coral reefs. However, some coral genera show resistance to declines in seawater pH, potentially achieved by modulating the chemistry of the fluid where calcification occurs. We use two novel geochemical techniques based on boron systematics and Raman spectroscopy, which together provide the first constraints on the sensitivity of coral calcifying fluid calcium concentrations ([Formula: see text]) to changing seawater pH. In response to simulated end-of-century pH conditions, Pocillopora damicornis increased [Formula: see text] to as much as 25% above that of seawater and maintained constant calcification rates. Conversely, Acropora youngei displayed less control over [Formula: see text], and its calcification rates strongly declined at lower seawater pH. Although the role of [Formula: see text] in driving calcification has often been neglected, increasing [Formula: see text] may be a key mechanism enabling more resistant corals to cope with ocean acidification and continue to build CaCO3 skeletons in a high-CO2 world.
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Affiliation(s)
- T M DeCarlo
- Oceans Institute and Oceans Graduate School, The University of Western Australia, 35 Stirling Hwy, Crawley, Western Australia 6009, Australia .,ARC Centre of Excellence for Coral Reef Studies, The University of Western Australia, 35 Stirling Hwy, Crawley, Western Australia 6009, Australia
| | - S Comeau
- Oceans Institute and Oceans Graduate School, The University of Western Australia, 35 Stirling Hwy, Crawley, Western Australia 6009, Australia.,ARC Centre of Excellence for Coral Reef Studies, The University of Western Australia, 35 Stirling Hwy, Crawley, Western Australia 6009, Australia
| | - C E Cornwall
- Oceans Institute and Oceans Graduate School, The University of Western Australia, 35 Stirling Hwy, Crawley, Western Australia 6009, Australia.,ARC Centre of Excellence for Coral Reef Studies, The University of Western Australia, 35 Stirling Hwy, Crawley, Western Australia 6009, Australia
| | - M T McCulloch
- Oceans Institute and Oceans Graduate School, The University of Western Australia, 35 Stirling Hwy, Crawley, Western Australia 6009, Australia.,ARC Centre of Excellence for Coral Reef Studies, The University of Western Australia, 35 Stirling Hwy, Crawley, Western Australia 6009, Australia
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14
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Comeau S, Cornwall CE, DeCarlo TM, Krieger E, McCulloch MT. Similar controls on calcification under ocean acidification across unrelated coral reef taxa. Glob Chang Biol 2018; 24:4857-4868. [PMID: 29957854 DOI: 10.1111/gcb.14379] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 06/07/2018] [Accepted: 06/12/2018] [Indexed: 05/13/2023]
Abstract
Ocean acidification (OA) is a major threat to marine ecosystems, particularly coral reefs which are heavily reliant on calcareous species. OA decreases seawater pH and calcium carbonate saturation state (Ω), and increases the concentration of dissolved inorganic carbon (DIC). Intense scientific effort has attempted to determine the mechanisms via which ocean acidification (OA) influences calcification, led by early hypotheses that calcium carbonate saturation state (Ω) is the main driver. We grew corals and coralline algae for 8-21 weeks, under treatments where the seawater parameters Ω, pH, and DIC were manipulated to examine their differential effects on calcification rates and calcifying fluid chemistry (Ωcf , pHcf , and DICcf ). Here, using long duration experiments, we provide geochemical evidence that differing physiological controls on carbonate chemistry at the site of calcification, rather than seawater Ω, are the main determinants of calcification. We found that changes in seawater pH and DIC rather than Ω had the greatest effects on calcification and calcifying fluid chemistry, though the effects of seawater carbonate chemistry were limited. Our results demonstrate the capacity of organisms from taxa with vastly different calcification mechanisms to regulate their internal chemistry under extreme chemical conditions. These findings provide an explanation for the resistance of some species to OA, while also demonstrating how changes in seawater DIC and pH under OA influence calcification of key coral reef taxa.
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Affiliation(s)
- Steeve Comeau
- Oceans Graduate School, The University of Western Australia, Crawley, WA, Australia
- ARC Centre of Excellence for Coral Reef Studies, Crawley, WA, Australia
- Laboratoire d'Océanographie de Villefranche, CNRS-INSU, Sorbonne Université, Villefranche-sur-mer, France
| | - Christopher E Cornwall
- Oceans Graduate School, The University of Western Australia, Crawley, WA, Australia
- ARC Centre of Excellence for Coral Reef Studies, Crawley, WA, Australia
| | - Thomas M DeCarlo
- Oceans Graduate School, The University of Western Australia, Crawley, WA, Australia
- ARC Centre of Excellence for Coral Reef Studies, Crawley, WA, Australia
| | - Erik Krieger
- Oceans Graduate School, The University of Western Australia, Crawley, WA, Australia
- Fachbereich 2 Biologie/Chemie, University of Bremen, Bremen, Germany
| | - Malcolm T McCulloch
- Oceans Graduate School, The University of Western Australia, Crawley, WA, Australia
- ARC Centre of Excellence for Coral Reef Studies, Crawley, WA, Australia
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Cornwall CE, Comeau S, DeCarlo TM, Moore B, D'Alexis Q, McCulloch MT. Resistance of corals and coralline algae to ocean acidification: physiological control of calcification under natural pH variability. Proc Biol Sci 2018; 285:rspb.2018.1168. [PMID: 30089625 DOI: 10.1098/rspb.2018.1168] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 07/13/2018] [Indexed: 12/31/2022] Open
Abstract
Ocean acidification is a threat to the continued accretion of coral reefs, though some undergo daily fluctuations in pH exceeding declines predicted by 2100. We test whether exposure to greater pH variability enhances resistance to ocean acidification for the coral Goniopora sp. and coralline alga Hydrolithon reinboldii from two sites: one with low pH variability (less than 0.15 units daily; Shell Island) and a site with high pH variability (up to 1.4 pH units daily; Tallon Island). We grew populations of both species for more than 100 days under a combination of differing pH variability (high/low) and means (ambient pH 8.05/ocean acidification pH 7.65). Calcification rates of Goniopora sp. were unaffected by the examined variables. Calcification rates of H. reinboldii were significantly faster in Tallon than in Shell Island individuals, and Tallon Island individuals calcified faster in the high variability pH 8.05 treatment compared with all others. Geochemical proxies for carbonate chemistry within the calcifying fluid (cf) of both species indicated that only mean seawater pH influenced pHcf pH treatments had no effect on proxies for Ωcf These limited responses to extreme pH treatments demonstrate that some calcifying taxa may be capable of maintaining constant rates of calcification under ocean acidification by actively modifying Ωcf.
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Affiliation(s)
- C E Cornwall
- Oceans Graduate School and Oceans Institute, The University of Western Australia, 35 Stirling Highway, Crawley 6009 Western Australia, Australia .,ARC Centre for Coral Reef Studies, 35 Stirling Highway, Crawley, 6009 Western Australia, Australia
| | - S Comeau
- Oceans Graduate School and Oceans Institute, The University of Western Australia, 35 Stirling Highway, Crawley 6009 Western Australia, Australia.,ARC Centre for Coral Reef Studies, 35 Stirling Highway, Crawley, 6009 Western Australia, Australia
| | - T M DeCarlo
- Oceans Graduate School and Oceans Institute, The University of Western Australia, 35 Stirling Highway, Crawley 6009 Western Australia, Australia.,ARC Centre for Coral Reef Studies, 35 Stirling Highway, Crawley, 6009 Western Australia, Australia
| | - B Moore
- Oceans Graduate School and Oceans Institute, The University of Western Australia, 35 Stirling Highway, Crawley 6009 Western Australia, Australia
| | - Q D'Alexis
- Oceans Graduate School and Oceans Institute, The University of Western Australia, 35 Stirling Highway, Crawley 6009 Western Australia, Australia
| | - M T McCulloch
- Oceans Graduate School and Oceans Institute, The University of Western Australia, 35 Stirling Highway, Crawley 6009 Western Australia, Australia.,ARC Centre for Coral Reef Studies, 35 Stirling Highway, Crawley, 6009 Western Australia, Australia
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Comeau S, Tambutté E, Carpenter RC, Edmunds PJ, Evensen NR, Allemand D, Ferrier-Pagès C, Tambutté S, Venn AA. Coral calcifying fluid pH is modulated by seawater carbonate chemistry not solely seawater pH. Proc Biol Sci 2018; 284:rspb.2016.1669. [PMID: 28100813 DOI: 10.1098/rspb.2016.1669] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 12/02/2016] [Indexed: 11/12/2022] Open
Abstract
Reef coral calcification depends on regulation of pH in the internal calcifying fluid (CF) in which the coral skeleton forms. However, little is known about calcifying fluid pH (pHCF) regulation, despite its importance in determining the response of corals to ocean acidification. Here, we investigate pHCF in the coral Stylophora pistillata in seawater maintained at constant pH with manipulated carbonate chemistry to alter dissolved inorganic carbon (DIC) concentration, and therefore total alkalinity (AT). We also investigate the intracellular pH of calcifying cells, photosynthesis, respiration and calcification rates under the same conditions. Our results show that despite constant pH in the surrounding seawater, pHCF is sensitive to shifts in carbonate chemistry associated with changes in [DIC] and [AT], revealing that seawater pH is not the sole driver of pHCF Notably, when we synthesize our results with published data, we identify linear relationships of pHCF with the seawater [DIC]/[H+] ratio, [AT]/ [H+] ratio and [[Formula: see text]]. Our findings contribute new insights into the mechanisms determining the sensitivity of coral calcification to changes in seawater carbonate chemistry, which are needed for predicting effects of environmental change on coral reefs and for robust interpretations of isotopic palaeoenvironmental records in coral skeletons.
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Affiliation(s)
- S Comeau
- Department of Biology, California State University, 18111 Nordhoff Street, Northridge, CA 91330-8303, USA .,School of Earth and Environment and ARC Centre of Excellence for Coral Reef Studies, The University of Western Australia, Crawley, Western Australia 6009, Australia
| | - E Tambutté
- Marine Biology Department, Centre Scientifique de Monaco, 8 Quai Antoine 1er, MC98000, Monaco.,Laboratoire International Associé 647 «BIOSENSIB», Centre Scientifique de Monaco-Centre National de la Recherche Scientifique, 8 Quai Antoine 1er, MC98000, Monaco
| | - R C Carpenter
- Department of Biology, California State University, 18111 Nordhoff Street, Northridge, CA 91330-8303, USA
| | - P J Edmunds
- Department of Biology, California State University, 18111 Nordhoff Street, Northridge, CA 91330-8303, USA
| | - N R Evensen
- Department of Biology, California State University, 18111 Nordhoff Street, Northridge, CA 91330-8303, USA.,Marine Spatial Ecology Lab, ARC Centre of Excellence for Coral Reef Studies and School of Biological Sciences, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - D Allemand
- Marine Biology Department, Centre Scientifique de Monaco, 8 Quai Antoine 1er, MC98000, Monaco.,Laboratoire International Associé 647 «BIOSENSIB», Centre Scientifique de Monaco-Centre National de la Recherche Scientifique, 8 Quai Antoine 1er, MC98000, Monaco
| | - C Ferrier-Pagès
- Marine Biology Department, Centre Scientifique de Monaco, 8 Quai Antoine 1er, MC98000, Monaco.,Laboratoire International Associé 647 «BIOSENSIB», Centre Scientifique de Monaco-Centre National de la Recherche Scientifique, 8 Quai Antoine 1er, MC98000, Monaco
| | - S Tambutté
- Marine Biology Department, Centre Scientifique de Monaco, 8 Quai Antoine 1er, MC98000, Monaco.,Laboratoire International Associé 647 «BIOSENSIB», Centre Scientifique de Monaco-Centre National de la Recherche Scientifique, 8 Quai Antoine 1er, MC98000, Monaco
| | - A A Venn
- Marine Biology Department, Centre Scientifique de Monaco, 8 Quai Antoine 1er, MC98000, Monaco .,Laboratoire International Associé 647 «BIOSENSIB», Centre Scientifique de Monaco-Centre National de la Recherche Scientifique, 8 Quai Antoine 1er, MC98000, Monaco
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Le Nohaïc M, Ross CL, Cornwall CE, Comeau S, Lowe R, McCulloch MT, Schoepf V. Marine heatwave causes unprecedented regional mass bleaching of thermally resistant corals in northwestern Australia. Sci Rep 2017; 7:14999. [PMID: 29101362 PMCID: PMC5670227 DOI: 10.1038/s41598-017-14794-y] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 10/16/2017] [Indexed: 11/09/2022] Open
Abstract
In 2015/16, a marine heatwave associated with a record El Niño led to the third global mass bleaching event documented to date. This event impacted coral reefs around the world, including in Western Australia (WA), although WA reefs had largely escaped bleaching during previous strong El Niño years. Coral health surveys were conducted during the austral summer of 2016 in four bioregions along the WA coast (~17 degrees of latitude), ranging from tropical to temperate locations. Here we report the first El Niño-related regional-scale mass bleaching event in WA. The heatwave primarily affected the macrotidal Kimberley region in northwest WA (~16°S), where 4.5-9.3 degree heating weeks (DHW) resulted in 56.6-80.6% bleaching, demonstrating that even heat-tolerant corals from naturally extreme, thermally variable reef environments are threatened by heatwaves. Some heat stress (2.4 DHW) and bleaching (<30%) also occurred at Rottnest Island (32°01'S), whereas coral communities at Ningaloo Reef (23°9'S) and Bremer Bay (34°25'S) were not impacted. The only other major mass bleaching in WA occurred during a strong La Niña event in 2010/11 and primarily affected reefs along the central-to-southern coast. This suggests that WA reefs are now at risk of severe bleaching during both El Niño and La Niña years.
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Affiliation(s)
- Morane Le Nohaïc
- ARC Centre of Excellence for Coral Reef Studies, UWA Oceans Institute and School of Earth Sciences, The University of Western Australia, Perth, WA, Australia
| | - Claire L Ross
- ARC Centre of Excellence for Coral Reef Studies, UWA Oceans Institute and School of Earth Sciences, The University of Western Australia, Perth, WA, Australia
| | - Christopher E Cornwall
- ARC Centre of Excellence for Coral Reef Studies, UWA Oceans Institute and School of Earth Sciences, The University of Western Australia, Perth, WA, Australia
| | - Steeve Comeau
- ARC Centre of Excellence for Coral Reef Studies, UWA Oceans Institute and School of Earth Sciences, The University of Western Australia, Perth, WA, Australia
| | - Ryan Lowe
- ARC Centre of Excellence for Coral Reef Studies, UWA Oceans Institute and School of Earth Sciences, The University of Western Australia, Perth, WA, Australia.,The Western Australian Marine Science Institution, Perth, WA, Australia
| | - Malcolm T McCulloch
- ARC Centre of Excellence for Coral Reef Studies, UWA Oceans Institute and School of Earth Sciences, The University of Western Australia, Perth, WA, Australia.,The Western Australian Marine Science Institution, Perth, WA, Australia
| | - Verena Schoepf
- ARC Centre of Excellence for Coral Reef Studies, UWA Oceans Institute and School of Earth Sciences, The University of Western Australia, Perth, WA, Australia. .,The Western Australian Marine Science Institution, Perth, WA, Australia.
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Cornwall CE, Comeau S, McCulloch MT. Coralline algae elevate pH at the site of calcification under ocean acidification. Glob Chang Biol 2017; 23:4245-4256. [PMID: 28370806 DOI: 10.1111/gcb.13673] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2016] [Revised: 02/15/2017] [Accepted: 02/20/2017] [Indexed: 05/10/2023]
Abstract
Coralline algae provide important ecosystem services but are susceptible to the impacts of ocean acidification. However, the mechanisms are uncertain, and the magnitude is species specific. Here, we assess whether species-specific responses to ocean acidification of coralline algae are related to differences in pH at the site of calcification within the calcifying fluid/medium (pHcf ) using δ11 B as a proxy. Declines in δ11 B for all three species are consistent with shifts in δ11 B expected if B(OH)4- was incorporated during precipitation. In particular, the δ11 B ratio in Amphiroa anceps was too low to allow for reasonable pHcf values if B(OH)3 rather than B(OH)4- was directly incorporated from the calcifying fluid. This points towards δ11 B being a reliable proxy for pHcf for coralline algal calcite and that if B(OH)3 is present in detectable proportions, it can be attributed to secondary postincorporation transformation of B(OH)4- . We thus show that pHcf is elevated during calcification and that the extent is species specific. The net calcification of two species of coralline algae (Sporolithon durum, and Amphiroa anceps) declined under elevated CO2 , as did their pHcf . Neogoniolithon sp. had the highest pHcf , and most constant calcification rates, with the decrease in pHcf being ¼ that of seawater pH in the treatments, demonstrating a control of coralline algae on carbonate chemistry at their site of calcification. The discovery that coralline algae upregulate pHcf under ocean acidification is physiologically important and should be included in future models involving calcification.
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Affiliation(s)
- Christopher E Cornwall
- School of Earth Sciences and Oceans Institute, The University of Western Australia, Crawley, WA, Australia
- ARC Centre of Excellence for Coral Reef Studies, The University of Western Australia, Crawley, WA, Australia
| | - Steeve Comeau
- School of Earth Sciences and Oceans Institute, The University of Western Australia, Crawley, WA, Australia
- ARC Centre of Excellence for Coral Reef Studies, The University of Western Australia, Crawley, WA, Australia
| | - Malcolm T McCulloch
- School of Earth Sciences and Oceans Institute, The University of Western Australia, Crawley, WA, Australia
- ARC Centre of Excellence for Coral Reef Studies, The University of Western Australia, Crawley, WA, Australia
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Edmunds PJ, Comeau S, Lantz C, Andersson A, Briggs C, Cohen A, Gattuso JP, Grady JM, Gross K, Johnson M, Muller EB, Ries JB, Tambutté S, Tambutté E, Venn A, Carpenter RC. Integrating the Effects of Ocean Acidification across Functional Scales on Tropical Coral Reefs. Bioscience 2016. [DOI: 10.1093/biosci/biw023] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Comeau S, Lantz CA, Edmunds PJ, Carpenter RC. Framework of barrier reefs threatened by ocean acidification. Glob Chang Biol 2016; 22:1225-1234. [PMID: 26154126 DOI: 10.1111/gcb.13023] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Accepted: 05/29/2015] [Indexed: 06/04/2023]
Abstract
To date, studies of ocean acidification (OA) on coral reefs have focused on organisms rather than communities, and the few community effects that have been addressed have focused on shallow back reef habitats. The effects of OA on outer barrier reefs, which are the most striking of coral reef habitats and are functionally and physically different from back reefs, are unknown. Using 5-m long outdoor flumes to create treatment conditions, we constructed coral reef communities comprised of calcified algae, corals, and reef pavement that were assembled to match the community structure at 17 m depth on the outer barrier reef of Moorea, French Polynesia. Communities were maintained under ambient and 1200 μatm pCO2 for 7 weeks, and net calcification rates were measured at different flow speeds. Community net calcification was significantly affected by OA, especially at night when net calcification was depressed ~78% compared to ambient pCO2 . Flow speed (2-14 cm s(-1) ) enhanced net calcification only at night under elevated pCO2 . Reef pavement also was affected by OA, with dissolution ~86% higher under elevated pCO2 compared to ambient pCO2 . These results suggest that net accretion of outer barrier reef communities will decline under OA conditions predicted within the next 100 years, largely because of increased dissolution of reef pavement. Such extensive dissolution poses a threat to the carbonate foundation of barrier reef communities.
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Affiliation(s)
- Steeve Comeau
- Department of Biology, California State University, 18111 Nordhoff Street, Northridge, CA, 91330-8303, USA
- ARC Centre of Excellence in Coral Reef Studies, The University of Western Australia, School of Earth & Environment & Ocean's Institute, Western Australia 6009, Australia
| | - Coulson A Lantz
- Department of Biology, California State University, 18111 Nordhoff Street, Northridge, CA, 91330-8303, USA
- ARC Centre of Excellence in Coral Reef Studies, The University of Western Australia, School of Earth & Environment & Ocean's Institute, Western Australia 6009, Australia
| | - Peter J Edmunds
- Department of Biology, California State University, 18111 Nordhoff Street, Northridge, CA, 91330-8303, USA
- ARC Centre of Excellence in Coral Reef Studies, The University of Western Australia, School of Earth & Environment & Ocean's Institute, Western Australia 6009, Australia
| | - Robert C Carpenter
- Department of Biology, California State University, 18111 Nordhoff Street, Northridge, CA, 91330-8303, USA
- ARC Centre of Excellence in Coral Reef Studies, The University of Western Australia, School of Earth & Environment & Ocean's Institute, Western Australia 6009, Australia
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Comeau S, Carpenter RC, Nojiri Y, Putnam HM, Sakai K, Edmunds PJ. Pacific-wide contrast highlights resistance of reef calcifiers to ocean acidification. Proc Biol Sci 2015; 281:rspb.2014.1339. [PMID: 25056628 DOI: 10.1098/rspb.2014.1339] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Ocean acidification (OA) and its associated decline in calcium carbonate saturation states is one of the major threats that tropical coral reefs face this century. Previous studies of the effect of OA on coral reef calcifiers have described a wide variety of outcomes for studies using comparable partial pressure of CO2 (pCO2) ranges, suggesting that key questions remain unresolved. One unresolved hypothesis posits that heterogeneity in the response of reef calcifiers to high pCO2 is a result of regional-scale variation in the responses to OA. To test this hypothesis, we incubated two coral taxa (Pocillopora damicornis and massive Porites) and two calcified algae (Porolithon onkodes and Halimeda macroloba) under 400, 700 and 1000 μatm pCO2 levels in experiments in Moorea (French Polynesia), Hawaii (USA) and Okinawa (Japan), where environmental conditions differ. Both corals and H. macroloba were insensitive to OA at all three locations, while the effects of OA on P. onkodes were location-specific. In Moorea and Hawaii, calcification of P. onkodes was depressed by high pCO2, but for specimens in Okinawa, there was no effect of OA. Using a study of large geographical scale, we show that resistance to OA of some reef species is a constitutive character expressed across the Pacific.
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Affiliation(s)
- S Comeau
- Department of Biology, California State University, 18111 Nordhoff Street, Northridge, CA 91330-8303, USA
| | - R C Carpenter
- Department of Biology, California State University, 18111 Nordhoff Street, Northridge, CA 91330-8303, USA
| | - Y Nojiri
- Center for Global Environment Research, National Institute for Environmental Studies, 16-2, Onogawa, Tsukuba, Ibaraki 305-8506, Japan
| | - H M Putnam
- Hawaii Institute of Marine Biology, University of Hawaii, PO Box 1346, Kaneohe, HI 96744, USA
| | - K Sakai
- Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, Sesoko, Motobu, Okinawa 905-0227, Japan
| | - P J Edmunds
- Department of Biology, California State University, 18111 Nordhoff Street, Northridge, CA 91330-8303, USA
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Comeau S, Carpenter RC, Edmunds PJ. Response to coral reef calcification: carbonate, bicarbonate and proton flux under conditions of increasing ocean acidification. Proc Biol Sci 2013; 280:20131153. [PMID: 23760868 DOI: 10.1098/rspb.2013.1153] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- S Comeau
- Department of Biology, California State University, 18111 Nordhoff Street, Northridge, CA 91330-8303, USA
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Comeau S, Carpenter RC, Edmunds PJ. Coral reef calcifiers buffer their response to ocean acidification using both bicarbonate and carbonate. Proc Biol Sci 2012; 280:20122374. [PMID: 23256193 DOI: 10.1098/rspb.2012.2374] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Central to evaluating the effects of ocean acidification (OA) on coral reefs is understanding how calcification is affected by the dissolution of CO(2) in sea water, which causes declines in carbonate ion concentration [CO(3)(2-)] and increases in bicarbonate ion concentration [HCO(3)(-)]. To address this topic, we manipulated [CO(3)(2-)] and [HCO(3)(-)] to test the effects on calcification of the coral Porites rus and the alga Hydrolithon onkodes, measured from the start to the end of a 15-day incubation, as well as in the day and night. [CO(3)(2-)] played a significant role in light and dark calcification of P. rus, whereas [HCO(3)(-)] mainly affected calcification in the light. Both [CO(3)(2-)] and [HCO(3)(-)] had a significant effect on the calcification of H. onkodes, but the strongest relationship was found with [CO(3)(2-)]. Our results show that the negative effect of declining [CO(3)(2-)] on the calcification of corals and algae can be partly mitigated by the use of HCO(3)(-) for calcification and perhaps photosynthesis. These results add empirical support to two conceptual models that can form a template for further research to account for the calcification response of corals and crustose coralline algae to OA.
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Affiliation(s)
- S Comeau
- Department of Biology, California State University, 18111 Nordhoff Street, Northridge, CA 91330-8303, USA.
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Abstract
Thecosome pteropods play a key role in the food web of various marine ecosystems and they calcify, secreting the unstable CaCO(3) mineral aragonite to form their shell material. Here, we have estimated the effect of ocean acidification on pteropod calcification by exploiting empirical relationships between their gross calcification rates (CaCO(3) precipitation) and aragonite saturation state Ω(a), combined with model projections of future Ω(a). These were corrected for modern model-data bias and taken over the depth range where pteropods are observed to migrate vertically. Results indicate large reductions in gross calcification at temperate and high latitudes. Over much of the Arctic, the pteropod Limacina helicina will become unable to precipitate CaCO(3) by the end of the century under the IPCC SRES A2 scenario. These results emphasize concerns over the future of shelled pteropods, particularly L. helicina in high latitudes. Shell-less L. helicina are not known to have ever existed nor would we expect them to survive. Declines of pteropod populations could drive dramatic ecological changes in the various pelagic ecosystems in which they play a critical role.
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Affiliation(s)
- Steeve Comeau
- CNRS-INSU, Laboratoire d'Océanographie de Villefranche, BP 28, 06234 Villefranche-sur-Mer Cedex, France.
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Comeau S, Jeffree R, Teyssié JL, Gattuso JP. Response of the Arctic pteropod Limacina helicina to projected future environmental conditions. PLoS One 2010; 5:e11362. [PMID: 20613868 PMCID: PMC2894046 DOI: 10.1371/journal.pone.0011362] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Accepted: 06/04/2010] [Indexed: 11/19/2022] Open
Abstract
Thecosome pteropods (pelagic mollusks) can play a key role in the food web of various marine ecosystems. They are a food source for zooplankton or higher predators such as fishes, whales and birds that is particularly important in high latitude areas. Since they harbor a highly soluble aragonitic shell, they could be very sensitive to ocean acidification driven by the increase of anthropogenic CO2 emissions. The effect of changes in the seawater chemistry was investigated on Limacina helicina, a key species of Arctic pelagic ecosystems. Individuals were kept in the laboratory under controlled pCO2 levels of 280, 380, 550, 760 and 1020 µatm and at control (0°C) and elevated (4°C) temperatures. The respiration rate was unaffected by pCO2 at control temperature, but significantly increased as a function of the pCO2 level at elevated temperature. pCO2 had no effect on the gut clearance rate at either temperature. Precipitation of CaCO3, measured as the incorporation of 45Ca, significantly declined as a function of pCO2 at both temperatures. The decrease in calcium carbonate precipitation was highly correlated to the aragonite saturation state. Even though this study demonstrates that pteropods are able to precipitate calcium carbonate at low aragonite saturation state, the results support the current concern for the future of Arctic pteropods, as the production of their shell appears to be very sensitive to decreased pH. A decline of pteropod populations would likely cause dramatic changes to various pelagic ecosystems.
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Affiliation(s)
- Steeve Comeau
- Centre National de la Recherche Scientifique-Institut National des Sciences de l'Univers, Laboratoire d'Océanographie de Villefranche, Villefranche-sur-Mer, France.
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Tamarin O, Comeau S, Déjous C, Moynet D, Rebière D, Bezian J, Pistré J. Real time device for biosensing: design of a bacteriophage model using love acoustic waves. Biosens Bioelectron 2003; 18:755-63. [PMID: 12706589 DOI: 10.1016/s0956-5663(03)00022-8] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Love wave sensors (ST-cut quartz substrate with interdigital transducers, SiO(2) guiding layer and sensitive coating) have been receiving a great deal of attention for a few years. Indeed, the wave coupled in a guiding layer confers a high gravimetric sensitivity and the shear horizontal (SH) polarization allows to work in liquid media. In this paper, an analytical method is proposed to calculate the Love wave phase velocity and the gravimetric sensitivity for a complete multilayer structure. This allows us to optimize the Love wave devices design in order to improve their gravimetric sensitivity in liquid media. As a model for virus or bacteria detection in liquids (drinking or bathing water, food em leader ) we design a model using M13 bacteriophage. The first step is the anti-M13 (AM13) monoclonal antibody grafting, on the device surface (SiO(2)). The second step is an immunoreaction in between the M13 bacteriophage and the AM13 antibody. The Love wave device allows to detect in real time the graft of the AM13 sensitive coating, as well as the immobilization of the M13 bacteriophages. With a pH change, the M13 bacteriophages can be removed from the sensor surface, in order to be numerated as plaque forming unit (pfu). Results on the sensitivity of Love waves are compared with similar immunological works with bulk acoustic wave devices, and demonstrate the high potentialities of Love waves sensors.
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Affiliation(s)
- O Tamarin
- IXL (CNRS UMR 5818-ENSEIRB-Université Bordeaux1), 351 Cours de la Libération, 33045, Talence, France
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Wilens TE, Spencer TJ, Biederman J, Girard K, Doyle R, Prince J, Polisner D, Solhkhah R, Comeau S, Monuteaux MC, Parekh A. A controlled clinical trial of bupropion for attention deficit hyperactivity disorder in adults. Am J Psychiatry 2001; 158:282-8. [PMID: 11156812 DOI: 10.1176/appi.ajp.158.2.282] [Citation(s) in RCA: 165] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Despite the increasing recognition of attention deficit hyperactivity disorder (ADHD) in adults, there is a paucity of controlled pharmacological trials demonstrating the effectiveness of compounds used in treatment, particularly nonstimulants. The authors report results from a controlled investigation to determine the anti-ADHD efficacy of bupropion in adult patients with DSM-IV ADHD. METHOD This was a double-blind, placebo-controlled, randomized, parallel, 6-week trial comparing patients receiving sustained-release bupropion (up to 200 mg b.i.d.) (N=21) to patients receiving placebo (N=19). The authors used standardized structured psychiatric instruments for diagnosis of ADHD. To measure improvement, they used separate assessments of ADHD, depression, and anxiety symptoms at baseline and each weekly visit. RESULTS Of the 40 subjects (55% male) enrolled in the study, 38 completed the study. Bupropion treatment was associated with a significant change in ADHD symptoms at the week-6 endpoint (42% reduction), which exceeded the effects of placebo (24% reduction). In analyses using a cutoff of 30% or better reduction to denote response, 76% of the subjects receiving bupropion improved, compared to 37% of the subjects receiving placebo. Similarly, in analyses using Clinical Global Impression scale scores, 52% of the subjects receiving bupropion reported being "much improved" to "very improved," compared to 11% of the subjects receiving placebo. CONCLUSIONS These results indicate a clinically and statistically significant effect of bupropion in improving ADHD in adults. The results suggest a therapeutic role for bupropion in the armamentarium of agents for ADHD in adults, while further validating the continuity of pharmacological responsivity of ADHD across the lifespan.
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Affiliation(s)
- T E Wilens
- Pediatric Psychopharmacology Clinic, Massachusetts General Hospital, Boston, MA 02114, USA.
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Abstract
Two principal hypotheses account for intracardiac shunting in reptiles. The ‘pressure shunting’ hypothesis proposes that there is no fuctional separation between the ventricular cava during systole. The ‘washout shunting’ hypothesis suggests that the cavum pulmonale is functionally separated from the rest of the ventricle during systole. The purpose of this study was to test the two principal hypotheses in a turtle, Pseudemys scripta, after inducing a right-to-left shunt by electrical stimulation of the vagus nerve. Animals were anaesthetized with sodium pentobarbital (30–40 mg kg-1), tracheotomized and mechanically ventilated. Two experimental groups were used. Both groups had the right and left cervical vagi exposed and sectioned and silver bipolar electrodes were attached for electrical stimulation. In addition, cardiac function was evaluated by determining the pulmonary blood flow, pulmonary arterial pressure, peak systolic pressure in the cavum pulmonale, central arterial pressure, pulmonary vascular resistance and heart rate. In group I, hydrogen electrodes were inserted into the right aorta, the left aorta and the pulmonary artery. Hydrogen, dissolved in saline, was infused into the left atrium, jugular vein and cavum pulmonale. Blood flow from these sites was deduced from detection of a H2 signal in the right and left aortae and the pulmonary artery. In group II, catheters were inserted in the left and right atria and aortae for the measurement of blood gases. For both groups, the protocol consisted of control periods and periods of electrical stimulation of the efferent and afferent ends of the vagus nerve. During the control periods, infusion of a H2 solution into either the left atrium or the jugular vein resulted in the detection of H2 in the right and left aortae and the pulmonary artery. This suggested that both right-to-left and left-to-right intracardiac shunts were present. H2 infused into the cavum pulmonale was always detected in the pulmonary artery but never in the left or right aortae. During stimulation of the right vagal efferents, a bradycardia developed (heart rate declined by 65 %), pulmonary blood flow was reduced by 73 % and pulmonary vascular resistance increased by 158 %. This was accompanied by a reduction in the PO2 of both the right and left aortae, although the PO2 of the left and right atria remained constant. Under these conditions, H2 infused into the jugular vein and the left atrium was detected in the right and left aortae and the pulmonary artery of all animals studied. Infusion of H2 into the cavum pulmonale was detected in the right and left aortae in only two animals. The results supported the washout mechanism for right-to-left intracardiac shunting.
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Dalton MT, Comeau S, Rainnie B, Lambert K, Forward KR. A comparison of the API Uriscreen with the Vitek Urine Identification-3 and the leukocyte esterase or nitrite strip as a screening test for bacteriuria. Diagn Microbiol Infect Dis 1993; 16:93-7. [PMID: 8467632 DOI: 10.1016/0732-8893(93)90001-n] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The API Uriscreen is a rapid urine-screening test based on the detection of catalase activity present in somatic cells and in many of the bacteria commonly causing urinary tract infections. Of 487 routine, outpatient urine specimens processed by conventional quantitative culture, API Uriscreen, Vitek UID-3 panel, and a leukocyte esterase-nitrite strip, 142 had no growth. Of 336 urine specimens with > or = 10(3) colony-forming units (CFU)/ml, 79 were considered to be indicative of possible or probable urinary tract infection (Cumitech 2A). The sensitivity and specificity of the API Uriscreen for the detection of bacteriuria at > or = 10(5) CFU/ml were 62% and 85%, those of the leukocyte esterase-nitrite strip was 61% and 82%, those of the Vitek UID-3 panel were 91% and 66%. When bacteriurias were classified into possibly or probably indicative of urinary tract infection, the sensitivity and specificity of the API Uriscreen at > or = 10(5) CFU/ml were 87% and 78%, those of the leukocyte esterase-nitrite were 84% and 76%, those of the Vitek UID-3 were 93% and 55%. In this study, we consider the API Uriscreen did not have significant advantages over the leukocyte esterase-nitrite strip.
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Affiliation(s)
- M T Dalton
- Department of Microbiology, Victoria General Hospital, Halifax, Nova Scotia, Canada
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Abstract
Incubation of plasma form the alligator (Alligator mississipiensis) with glass beads in the presence of a kininase inhibitor resulted in the activation of the kallikrein-kinin system and generation of bradykinin-like immunoreactivity. The kinin peptides were purified to homogeneity and were shown to comprise [Thr6]-bradykinin and des-Arg9[Thr6]bradykinin in the molar ratio of approximately 10:1. Bolus injections of synthetic [Thr6]bradykinin into the jugular vein of the anesthetized alligator resulted in a dose-dependent decrease in mean arterial blood pressure. The minimum dose of kinin producing a significant fall in pressure was 0.07 micrograms/kg body wt and the maximum response (25 +/- 6% fall; mean +/- SD, n = 8) was produced by a dose of 0.56 micrograms/kg body wt. The dose producing a half-maximum response was 0.19 +/- 0.08 micrograms/kg. The data indicate that alligator plasma contains all the components of the kallikrein-kinin system found in mammals and suggest that the system may be of physiological importance in the regulation of cardiovascular function in these reptiles.
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Affiliation(s)
- S Comeau
- Regulatory Peptide Center, Creighton University School of Medicine, Omaha, Nebraska 68178
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Abstract
The articulation errors of one adult subject demonstrating a spastic variety of congenital cerebral palsy were evaluated via a phonological process analysis. This analysis indicated that a stopping process (replacement of fricatives with homorganic stops) was the most detrimental to the subject's, intelligibility. Subsequent to this analysis a phonemic contrasting programme was initiated toward the goal of minimizing the influence of the stopping process. Results of spontaneous speech sample analyses indicated that this approach was successful in increasing the percentage of correctly produced fricative patterns. Success in this case suggests the applicability of a linguistically based intervention approach in structural/functional disturbances of speech articulation.
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