1
|
Morris J, Enochs I, Webb A, de Bakker D, Soderberg N, Kolodziej G, Manzello D. The influences of diurnal variability and ocean acidification on the bioerosion rates of two reef-dwelling Caribbean sponges. GLOBAL CHANGE BIOLOGY 2022; 28:7126-7138. [PMID: 36129389 DOI: 10.1111/gcb.16442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 08/26/2022] [Indexed: 05/28/2023]
Abstract
Ocean acidification (OA) is expected to modify the structure and function of coral reef ecosystems by reducing calcification, increasing bioerosion, and altering the physiology of many marine organisms. Much of our understanding of these relationships is based on experiments with static OA treatments, although evidence suggests that the magnitude of diurnal fluctuations in carbonate chemistry may modulate the calcification response to OA. These light-mediated swings in seawater pH are projected to become more extreme with OA, yet their impact on bioerosion remains unknown. We evaluated the influence of diurnal carbonate chemistry variability on the bioerosion rates of two Caribbean sponges: the zooxanthellate Cliona varians and azooxanthellate Cliothosa delitrix. Replicate fragments from multiple colonies of each species were exposed to four precisely controlled pH treatments: contemporary static (8.05 ± 0.00; mean pH ± diurnal pH oscillation), contemporary variable (8.05 ± 0.10), future OA static (7.80 ± 0.00), and future OA variable (7.80 ± 0.10). Significantly enhanced bioerosion rates, determined using buoyant weight measurements, were observed under more variable conditions in both the contemporary and future OA scenarios for C. varians, whereas the same effect was only apparent under contemporary pH conditions for C. delitrix. These results indicate that variable carbonate chemistry has a stimulating influence on sponge bioerosion, and we hypothesize that bioerosion rates evolve non-linearly as a function of pCO2 resulting in different magnitudes and directions of rate enhancement/reduction between day and night, even with an equal fluctuation around the mean. This response appeared to be intensified by photosymbionts, evident by the consistently higher percent increase in bioerosion rates for photosynthetic C. varians across all treatments. These findings further suggest that more variable natural ecosystems may presently experience elevated sponge bioerosion rates and that the heightened impact of OA enhanced bioerosion on reef habitat could occur sooner than prior predictions.
Collapse
Affiliation(s)
- John Morris
- Ocean Chemistry and Ecosystem Division, NOAA, Atlantic Oceanographic and Meteorological Laboratory, Miami, Florida, USA
- Cooperative Institute for Marine and Atmospheric Studies, University of Miami, Miami, Florida, USA
| | - Ian Enochs
- Ocean Chemistry and Ecosystem Division, NOAA, Atlantic Oceanographic and Meteorological Laboratory, Miami, Florida, USA
| | - Alice Webb
- Ocean Chemistry and Ecosystem Division, NOAA, Atlantic Oceanographic and Meteorological Laboratory, Miami, Florida, USA
- Cooperative Institute for Marine and Atmospheric Studies, University of Miami, Miami, Florida, USA
| | - Didier de Bakker
- Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Nash Soderberg
- Ocean Chemistry and Ecosystem Division, NOAA, Atlantic Oceanographic and Meteorological Laboratory, Miami, Florida, USA
- Cooperative Institute for Marine and Atmospheric Studies, University of Miami, Miami, Florida, USA
| | - Graham Kolodziej
- Ocean Chemistry and Ecosystem Division, NOAA, Atlantic Oceanographic and Meteorological Laboratory, Miami, Florida, USA
- Cooperative Institute for Marine and Atmospheric Studies, University of Miami, Miami, Florida, USA
| | - Derek Manzello
- Satellite Oceanography & Climatology Division, Coral Reef Watch, Center for Satellite Applications and Research, U.S. National Oceanic and Atmospheric Administration, College Park, Maryland, USA
| |
Collapse
|
2
|
Brown KT, Mello-Athayde MA, Sampayo EM, Chai A, Dove S, Barott KL. Environmental memory gained from exposure to extreme pCO 2 variability promotes coral cellular acid-base homeostasis. Proc Biol Sci 2022; 289:20220941. [PMID: 36100023 PMCID: PMC9470260 DOI: 10.1098/rspb.2022.0941] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Ocean acidification is a growing threat to coral growth and the accretion of coral reef ecosystems. Corals inhabiting environments that already endure extreme diel pCO2 fluctuations, however, may represent acidification-resilient populations capable of persisting on future reefs. Here, we examined the impact of pCO2 variability on the reef-building coral Pocillopora damicornis originating from reefs with contrasting environmental histories (variable reef flat versus stable reef slope) following reciprocal exposure to stable (218 ± 9) or variable (911 ± 31) diel pCO2 amplitude (μtam) in aquaria over eight weeks. Endosymbiont density, photosynthesis and net calcification rates differed between origins but not treatment, whereas primary calcification (extension) was affected by both origin and acclimatization to novel pCO2 conditions. At the cellular level, corals from the variable reef flat exhibited less intracellular pH (pHi) acidosis and faster pHi recovery rates in response to experimental acidification stress (pH 7.40) than corals originating from the stable reef slope, suggesting environmental memory gained from lifelong exposure to pCO2 variability led to an improved ability to regulate acid–base homeostasis. These results highlight the role of cellular processes in maintaining acidification resilience and suggest that prior exposure to pCO2 variability may promote more acidification-resilient coral populations in a changing climate.
Collapse
Affiliation(s)
- Kristen T Brown
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA.,ARC Centre of Excellence for Coral Reef Studies and School of Biological Sciences, University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Matheus A Mello-Athayde
- ARC Centre of Excellence for Coral Reef Studies and School of Biological Sciences, University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Eugenia M Sampayo
- ARC Centre of Excellence for Coral Reef Studies and School of Biological Sciences, University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Aaron Chai
- ARC Centre of Excellence for Coral Reef Studies and School of Biological Sciences, University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Sophie Dove
- ARC Centre of Excellence for Coral Reef Studies and School of Biological Sciences, University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Katie L Barott
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| |
Collapse
|
3
|
Clark V, Mello-Athayde MA, Dove S. Colonies of Acropora formosa with greater survival potential have reduced calcification rates. PLoS One 2022; 17:e0269526. [PMID: 35679252 PMCID: PMC9182694 DOI: 10.1371/journal.pone.0269526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 05/23/2022] [Indexed: 11/18/2022] Open
Abstract
Coral reefs are facing increasingly devasting impacts from ocean warming and acidification due to anthropogenic climate change. In addition to reducing greenhouse gas emissions, potential solutions have focused either on reducing light stress during heating, or on the potential for identifying or engineering “super corals”. A large subset of these studies, however, have tended to focus primarily on the bleaching response of corals, and assume erroneously that corals that bleach earlier in a thermal event die first. Here, we explore how survival, observable bleaching, coral skeletal growth (as branch extension and densification), and coral tissue growth (protein and lipid concentrations) varies for conspecifics collected from distinctive reef zones at Heron Island on the Southern Great Barrier Reef. A reciprocal transplantation experiment was undertaken using the dominant reef building coral (Acropora formosa) between the highly variable reef flat and the less variable reef slope environments. Coral colonies originating from the reef flat had higher rates of survival and amassed greater protein densities but calcified at reduced rates compared to conspecifics originating from the reef slope. The energetics of both populations however potentially benefited from greater light intensity present in the shallows. Reef flat origin corals moved to the lower light intensity of the reef slope reduced protein density and calcification rates. For A. formosa, genetic differences, or long-term entrainment to a highly variable environment, appeared to promote coral survival at the expense of calcification. The response decouples coral survival from carbonate coral reef resilience, a response that was further exacerbated by reductions in irradiance. As we begin to discuss interventions necessitated by the CO2 that has already been released into the atmosphere, we need to prioritise our focus on the properties that maintain valuable carbonate ecosystems. Rapid and dense calcification by corals such as branching Acropora is essential to the ability of carbonate coral reefs to rebound following disturbance events and maintain 3D structure but may be the first property that is sacrificed to enable coral genet survival under stress.
Collapse
Affiliation(s)
- Vanessa Clark
- School of Biological Sciences, The University of Queensland, St. Lucia, Queensland, Australia
- ARC Centre of Excellence for Coral Reef Studies, The University of Queensland, St. Lucia, Queensland, Australia
- * E-mail:
| | - Matheus A. Mello-Athayde
- School of Biological Sciences, The University of Queensland, St. Lucia, Queensland, Australia
- ARC Centre of Excellence for Coral Reef Studies, The University of Queensland, St. Lucia, Queensland, Australia
| | - Sophie Dove
- School of Biological Sciences, The University of Queensland, St. Lucia, Queensland, Australia
- ARC Centre of Excellence for Coral Reef Studies, The University of Queensland, St. Lucia, Queensland, Australia
| |
Collapse
|
4
|
Mallon J, Banaszak AT, Donachie L, Exton D, Cyronak T, Balke T, Bass AM. A low-cost benthic incubation chamber for in-situ community metabolism measurements. PeerJ 2022; 10:e13116. [PMID: 35402104 PMCID: PMC8992662 DOI: 10.7717/peerj.13116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 02/23/2022] [Indexed: 01/12/2023] Open
Abstract
Benthic incubation chambers facilitate in-situ metabolism studies in shallow water environments. They are used to isolate the water surrounding a study organism or community so that changes in water chemistry can be quantified to characterise physiological processes such as photosynthesis, respiration, and calcification. Such field measurements capture the biological processes taking place within the benthic community while incorporating the influence of environmental variables that are often difficult to recreate in ex-situ settings. Variations in benthic chamber designs have evolved for a range of applications. In this study, we built upon previous designs to create a novel chamber, which is (1) low-cost and assembled without specialised equipment, (2) easily reproducible, (3) minimally invasive, (4) adaptable to varied substrates, and (5) comparable with other available designs in performance. We tested the design in the laboratory and field and found that it achieved the outlined objectives. Using non-specialised materials, we were able to construct the chamber at a low cost (under $20 USD per unit), while maintaining similar performance and reproducibility with that of existing designs. Laboratory and field tests demonstrated minimal leakage (2.08 ± 0.78% water exchange over 4 h) and acceptable light transmission (86.9 ± 1.9%), results comparable to those reported for other chambers. In the field, chambers were deployed in a shallow coastal environment in Akumal, Mexico, to measure productivity of seagrass, and coral-, algae-, and sand-dominated reef patches. In both case studies, production rates aligned with those of comparable benthic chamber deployments in the literature and followed established trends with light, the primary driver of benthic metabolism, indicating robust performance under field conditions. We demonstrate that our low-cost benthic chamber design uses locally accessible and minimal resources, is adaptable for a variety of field settings, and can be used to collect reliable and repeatable benthic metabolism data. This chamber has the potential to broaden accessibility and applications of in-situ incubations for future studies.
Collapse
Affiliation(s)
- Jennifer Mallon
- School of Geographical and Earth Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Anastazia T. Banaszak
- Unidad Académica de Sistemas Arrecifales, Universidad Nacional Autónoma de México, Puerto Morelos, Quintana Roo, Mexico
| | | | - Dan Exton
- Operation Wallacea, Spilsby, Lincolnshire, United Kingdom
| | - Tyler Cyronak
- Department of Marine and Environmental Sciences, Halmos College of Natural Sciences and Oceanography, Nova Southeastern University, Dania Beach, Florida, United States
| | - Thorsten Balke
- School of Geographical and Earth Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Adrian M. Bass
- School of Geographical and Earth Sciences, University of Glasgow, Glasgow, United Kingdom
| |
Collapse
|
5
|
Jellison BM, Elsmore KE, Miller JT, Ng G, Ninokawa AT, Hill TM, Gaylord B. Low-pH seawater alters indirect interactions in rocky-shore tidepools. Ecol Evol 2022; 12:e8607. [PMID: 35169457 PMCID: PMC8840877 DOI: 10.1002/ece3.8607] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 01/11/2022] [Accepted: 01/14/2022] [Indexed: 11/24/2022] Open
Abstract
Ocean acidification is expected to degrade marine ecosystems, yet most studies focus on organismal-level impacts rather than ecological perturbations. Field studies are especially sparse, particularly ones examining shifts in direct and indirect consumer interactions. Here we address such connections within tidepool communities of rocky shores, focusing on a three-level food web involving the keystone sea star predator, Pisaster ochraceus, a common herbivorous snail, Tegula funebralis, and a macroalgal basal resource, Macrocystis pyrifera. We demonstrate that during nighttime low tides, experimentally manipulated declines in seawater pH suppress the anti-predator behavior of snails, bolstering their grazing, and diminishing the top-down influence of predators on basal resources. This attenuation of top-down control is absent in pools maintained experimentally at higher pH. These findings suggest that as ocean acidification proceeds, shifts of behaviorally mediated links in food webs could change how cascading effects of predators manifest within marine communities.
Collapse
Affiliation(s)
- Brittany M. Jellison
- Department of Biological SciencesUniversity of New HampshireDurhamNew HampshireUSA
| | - Kristen E. Elsmore
- Bodega Marine LaboratoryUniversity of California DavisBodega BayCaliforniaUSA
| | - Jeffrey T. Miller
- Minnesota Supercomputing InstituteUniversity of MinnesotaMinneapolisMinnesotaUSA
| | - Gabriel Ng
- Smithsonian Environmental Research CenterEdgewaterMarylandUSA
- Marine Invasions LaboratoryEstuary Ocean Science CenterTiburonCaliforniaUSA
| | - Aaron T. Ninokawa
- Bodega Marine LaboratoryUniversity of California DavisBodega BayCaliforniaUSA
| | - Tessa M. Hill
- Bodega Marine LaboratoryUniversity of California DavisBodega BayCaliforniaUSA
- Department of Earth and Planetary SciencesUniversity of California DavisDavisCaliforniaUSA
| | - Brian Gaylord
- Bodega Marine LaboratoryUniversity of California DavisBodega BayCaliforniaUSA
- Department of Evolution and EcologyUniversity of California DavisDavisCaliforniaUSA
| |
Collapse
|
6
|
Page CE, Leggat W, Heron SF, Fordyce AJ, Ainsworth TD. High flow conditions mediate damaging impacts of sub-lethal thermal stress on corals' endosymbiotic algae. CONSERVATION PHYSIOLOGY 2021; 9:coab046. [PMID: 34188937 PMCID: PMC8226191 DOI: 10.1093/conphys/coab046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 01/24/2021] [Accepted: 06/16/2021] [Indexed: 05/31/2023]
Abstract
The effects of thermal anomalies on tropical coral endosymbiosis can be mediated by a range of environmental factors, which in turn ultimately influence coral health and survival. One such factor is the water flow conditions over coral reefs and corals. Although the physiological benefits of living under high water flow are well known, there remains a lack of conclusive experimental evidence characterizing how flow mitigates thermal stress responses in corals. Here we use in situ measurements of flow in a variety of reef habitats to constrain the importance of flow speeds on the endosymbiosis of an important reef building species under different thermal regimes. Under high flow speeds (0.15 m s-1) and thermal stress, coral endosymbionts retained photosynthetic function and recovery capacity for longer compared to low flow conditions (0.03 m s-1). We hypothesize that this may be due to increased rates of mass transfer of key metabolites under higher flow, putatively allowing corals to maintain photosynthetic efficiency for longer. We also identified a positive interactive effect between high flow and a pre-stress, sub-lethal pulse in temperature. While higher flow may delay the onset of photosynthetic stress, it does not appear to confer long-term protection; sustained exposure to thermal stress (eDHW accumulation equivalent to 4.9°C weeks) eventually overwhelmed the coral meta-organism as evidenced by eventual declines in photo-physiological function and endosymbiont densities. Investigating flow patterns at the scale of metres within the context of these physiological impacts can reveal interesting avenues for coral reef management. This study increases our understanding of the effects of water flow on coral reef health in an era of climate change and highlights the potential to learn from existing beneficial bio-physical interactions for the effective preservation of coral reefs into the future.
Collapse
Affiliation(s)
- C E Page
- Life Sciences, Imperial College, Exhibition Road, London SW7 2AZ, UK
- School of Biological, Earth and Environmental Sciences, UNSW, Kensington, High St, New South Wales 2033, Australia
- School of Environmental and Life Sciences, University of Newcastle, University Dr, Callaghan, New South Wales 2308, Australia
| | - W Leggat
- School of Environmental and Life Sciences, University of Newcastle, University Dr, Callaghan, New South Wales 2308, Australia
| | - S F Heron
- Physics and Marine Geophysical Laboratory, College of Science and Engineering, James Cook University, James Cook Dr, Townsville, Queensland 4811, Australia
- NOAA Coral Reef Watch, College Park, MD 20740, USA
| | - A J Fordyce
- School of Environmental and Life Sciences, University of Newcastle, University Dr, Callaghan, New South Wales 2308, Australia
| | - T D Ainsworth
- School of Biological, Earth and Environmental Sciences, UNSW, Kensington, High St, New South Wales 2033, Australia
| |
Collapse
|
7
|
Dellisanti W, Chung JTH, Chow CFY, Wu J, Wells ML, Chan LL. Experimental Techniques to Assess Coral Physiology in situ Under Global and Local Stressors: Current Approaches and Novel Insights. Front Physiol 2021; 12:656562. [PMID: 34163371 PMCID: PMC8215126 DOI: 10.3389/fphys.2021.656562] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 04/09/2021] [Indexed: 11/19/2022] Open
Abstract
Coral reefs are declining worldwide due to global changes in the marine environment. The increasing frequency of massive bleaching events in the tropics is highlighting the need to better understand the stages of coral physiological responses to extreme conditions. Moreover, like many other coastal regions, coral reef ecosystems are facing additional localized anthropogenic stressors such as nutrient loading, increased turbidity, and coastal development. Different strategies have been developed to measure the health status of a damaged reef, ranging from the resolution of individual polyps to the entire coral community, but techniques for measuring coral physiology in situ are not yet widely implemented. For instance, while there are many studies of the coral holobiont response in single or limited-number multiple stressor experiments, they provide only partial insights into metabolic performance under more complex and temporally and spatially variable natural conditions. Here, we discuss the current status of coral reefs and their global and local stressors in the context of experimental techniques that measure core processes in coral metabolism (respiration, photosynthesis, and biocalcification) in situ, and their role in indicating the health status of colonies and communities. We highlight the need to improve the capability of in situ studies in order to better understand the resilience and stress response of corals under multiple global and local scale stressors.
Collapse
Affiliation(s)
- Walter Dellisanti
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, China.,Department of Biomedical Sciences, City University of Hong Kong, Kowloon, China
| | - Jeffery T H Chung
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, China
| | - Cher F Y Chow
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, China.,Centre for Biological Diversity, Scottish Oceans Institute, School of Biology, University of St Andrews, St Andrews, United Kingdom
| | - Jiajun Wu
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, China
| | - Mark L Wells
- School of Marine Sciences, University of Maine, Orono, ME, United States.,State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
| | - Leo L Chan
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, China.,Department of Biomedical Sciences, City University of Hong Kong, Kowloon, China.,Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, China
| |
Collapse
|
8
|
Boco SR, Pitt KA, Melvin SD. Coastal acidification and deoxygenation enhance settlement but do not influence movement behaviour of creeping polyps of the Irukandji jellyfish, Alatina alata (Cubozoa). MARINE ENVIRONMENTAL RESEARCH 2020; 162:105175. [PMID: 33070064 DOI: 10.1016/j.marenvres.2020.105175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 09/06/2020] [Accepted: 10/06/2020] [Indexed: 06/11/2023]
Abstract
Deoxygenation and acidification co-occur in many coastal ecosystems because nutrient enrichment produces excess organic matter that intensifies aerobic respiration during decomposition, thereby depleting O2, increasing CO2 and lowering pH. Despite this link between coastal deoxygenation (CD) and acidification (CA), and evidence that both stressors pose a risk to marine fauna, few studies have examined the effects of these drivers in combination on marine animals including invertebrates. Here, we studied the individual and combined effects of CD (~1.5 mg L-1 O2) and CA (~7.7 pH) on the survival, number of tentacles, settlement and movement behaviours of creeping polyps of the Irukandji jellyfish, Alatina alata. Low DO increased the survival rate (17% more) of the creeping polyps. 12% more creeping polyps settled in low pH than ambient pH and 16.7% more settled in low DO than ambient DO treatment. Exposure to CA and CD did not influence the number of tentacles, mobility or movement velocity of the creeping polyps, but after 4 h exposure to the treatments, they moved approximately half as fast. Our results indicate that CD can enhance survival and settlement success, but CA does not intensify these outcomes on A. alata creeping polyps.
Collapse
Affiliation(s)
- Sheldon Rey Boco
- Australian Rivers Institute, School of Environment and Science, Griffith University, Southport, Queensland, 4215, Australia.
| | - Kylie A Pitt
- Australian Rivers Institute, School of Environment and Science, Griffith University, Southport, Queensland, 4215, Australia
| | - Steven D Melvin
- Australian Rivers Institute, School of Environment and Science, Griffith University, Southport, Queensland, 4215, Australia
| |
Collapse
|
9
|
Tresguerres M, Clifford AM, Harter TS, Roa JN, Thies AB, Yee DP, Brauner CJ. Evolutionary links between intra- and extracellular acid-base regulation in fish and other aquatic animals. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2020; 333:449-465. [PMID: 32458594 DOI: 10.1002/jez.2367] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 03/10/2020] [Accepted: 05/06/2020] [Indexed: 12/17/2022]
Abstract
The acid-base relevant molecules carbon dioxide (CO2 ), protons (H+ ), and bicarbonate (HCO3 - ) are substrates and end products of some of the most essential physiological functions including aerobic and anaerobic respiration, ATP hydrolysis, photosynthesis, and calcification. The structure and function of many enzymes and other macromolecules are highly sensitive to changes in pH, and thus maintaining acid-base homeostasis in the face of metabolic and environmental disturbances is essential for proper cellular function. On the other hand, CO2 , H+ , and HCO3 - have regulatory effects on various proteins and processes, both directly through allosteric modulation and indirectly through signal transduction pathways. Life in aquatic environments presents organisms with distinct acid-base challenges that are not found in terrestrial environments. These include a relatively high CO2 relative to O2 solubility that prevents internal CO2 /HCO3 - accumulation to buffer pH, a lower O2 content that may favor anaerobic metabolism, and variable environmental CO2 , pH and O2 levels that require dynamic adjustments in acid-base homeostatic mechanisms. Additionally, some aquatic animals purposely create acidic or alkaline microenvironments that drive specialized physiological functions. For example, acidifying mechanisms can enhance O2 delivery by red blood cells, lead to ammonia trapping for excretion or buoyancy purposes, or lead to CO2 accumulation to promote photosynthesis by endosymbiotic algae. On the other hand, alkalinizing mechanisms can serve to promote calcium carbonate skeletal formation. This nonexhaustive review summarizes some of the distinct acid-base homeostatic mechanisms that have evolved in aquatic organisms to meet the particular challenges of this environment.
Collapse
Affiliation(s)
- Martin Tresguerres
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California, San Diego, California
| | - Alexander M Clifford
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California, San Diego, California
| | - Till S Harter
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California, San Diego, California
| | - Jinae N Roa
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California, San Diego, California
| | - Angus B Thies
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California, San Diego, California
| | - Daniel P Yee
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California, San Diego, California
| | - Colin J Brauner
- Department of Zoology, University of British Columbia, Vancouver, Canada
| |
Collapse
|
10
|
Lee YH, Jeong CB, Wang M, Hagiwara A, Lee JS. Transgenerational acclimation to changes in ocean acidification in marine invertebrates. MARINE POLLUTION BULLETIN 2020; 153:111006. [PMID: 32275552 DOI: 10.1016/j.marpolbul.2020.111006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 02/18/2020] [Accepted: 02/19/2020] [Indexed: 06/11/2023]
Abstract
The rapid pace of increasing oceanic acidity poses a major threat to the fitness of the marine ecosystem, as well as the buffering capacity of the oceans. Disruption in chemical equilibrium in the ocean leads to decreased carbonate ion precipitation, resulting in calcium carbonate saturation. If these trends continue, calcifying invertebrates will experience difficultly maintaining their calcium carbonate exoskeleton and shells. Because malfunction of exoskeleton formation by calcifiers in response to ocean acidification (OA) will have non-canonical biological cascading results in the marine ecosystem, many studies have investigated the direct and indirect consequences of OA on ecosystem- and physiology-related traits of marine invertebrates. Considering that evolutionary adaptation to OA depends on the duration of OA effects, long-term exposure to OA stress over multi-generations may result in adaptive mechanisms that increase the potential fitness of marine invertebrates in response to OA. Transgenerational studies have the potential to elucidate the roles of acclimation, carryover effects, and evolutionary adaptation within and over generations in response to OA. In particular, understanding mechanisms of transgenerational responses (e.g., antioxidant responses, metabolic changes, epigenetic reprogramming) to changes in OA will enhance our understanding of marine invertebrate in response to rapid climate change.
Collapse
Affiliation(s)
- Young Hwan Lee
- Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Chang-Bum Jeong
- Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea; Department of Marine Science, College of Nature Science, Incheon National University, Incheon 22012, South Korea
| | - Minghua Wang
- State Key Laboratory of Marine Environmental Science/College of the Environment & Ecology, Xiamen University, Xiamen 36110, China; Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, Xiamen University, Xiamen 361102, China
| | - Atsushi Hagiwara
- Institute of Integrated Science and Technology, Nagasaki University, Nagasaki 852-8521, Japan; Organization for Marine Science and Technology, Nagasaki University, Nagasaki 852-8521, Japan
| | - Jae-Seong Lee
- Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea.
| |
Collapse
|
11
|
Kline DI, Teneva L, Okamoto DK, Schneider K, Caldeira K, Miard T, Chai A, Marker M, Dunbar RB, Mitchell BG, Dove S, Hoegh-Guldberg O. Living coral tissue slows skeletal dissolution related to ocean acidification. Nat Ecol Evol 2019; 3:1438-1444. [PMID: 31558830 DOI: 10.1038/s41559-019-0988-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 08/19/2019] [Indexed: 11/09/2022]
Abstract
Climate change is causing major changes to marine ecosystems globally, with ocean acidification of particular concern for coral reefs. Using a 200 d in situ carbon dioxide enrichment study on Heron Island, Australia, we simulated future ocean acidification conditions, and found reduced pH led to a drastic decline in net calcification of living corals to no net growth, and accelerated disintegration of dead corals. Net calcification declined more severely than in previous studies due to exposure to the natural community of bioeroding organisms in this in situ study and to a longer experimental duration. Our data suggest that reef flat corals reach net dissolution at an aragonite saturation state (ΩAR) of 2.3 (95% confidence interval: 1.8-2.8) with 100% living coral cover and at ΩAR > 3.5 with 30% living coral cover. This model suggests that areas of the reef with relatively low coral mortality, where living coral cover is high, are likely to be resistant to carbon dioxide-induced reef dissolution.
Collapse
Affiliation(s)
- David I Kline
- Smithsonian Tropical Research Institute, Ancón, Panama. .,Scripps Institution of Oceanography, Integrative Oceanography Division, University of California San Diego, La Jolla, CA, USA. .,Global Change Institute and Coral Reef Ecosystems Laboratory, School of Biological Sciences, University of Queensland, St Lucia, Queensland, Australia. .,Australian Research Council Centre of Excellence for Coral Reef Studies, St Lucia, Queensland, Australia.
| | - Lida Teneva
- Environmental Earth System Science, Stanford University, Stanford, CA, USA.,OceanX, New York, NY, USA
| | - Daniel K Okamoto
- Department of Biological Science, Florida State University, Tallahassee, FL, USA
| | - Kenneth Schneider
- Department of Global Ecology, Carnegie Institution, Stanford, CA, USA.,Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Ken Caldeira
- Department of Global Ecology, Carnegie Institution, Stanford, CA, USA
| | - Thomas Miard
- Global Change Institute and Coral Reef Ecosystems Laboratory, School of Biological Sciences, University of Queensland, St Lucia, Queensland, Australia.,Australian Research Council Centre of Excellence for Coral Reef Studies, St Lucia, Queensland, Australia
| | - Aaron Chai
- Global Change Institute and Coral Reef Ecosystems Laboratory, School of Biological Sciences, University of Queensland, St Lucia, Queensland, Australia.,Australian Research Council Centre of Excellence for Coral Reef Studies, St Lucia, Queensland, Australia
| | - Malcolm Marker
- Faculty of Engineering, Architecture and Information Technology, University of Queensland, St Lucia, Australia
| | - Robert B Dunbar
- Environmental Earth System Science, Stanford University, Stanford, CA, USA
| | - B Greg Mitchell
- Scripps Institution of Oceanography, Integrative Oceanography Division, University of California San Diego, La Jolla, CA, USA
| | - Sophie Dove
- Global Change Institute and Coral Reef Ecosystems Laboratory, School of Biological Sciences, University of Queensland, St Lucia, Queensland, Australia.,Australian Research Council Centre of Excellence for Coral Reef Studies, St Lucia, Queensland, Australia
| | - Ove Hoegh-Guldberg
- Global Change Institute and Coral Reef Ecosystems Laboratory, School of Biological Sciences, University of Queensland, St Lucia, Queensland, Australia.,Australian Research Council Centre of Excellence for Coral Reef Studies, St Lucia, Queensland, Australia
| |
Collapse
|
12
|
Ocean acidification effects on in situ coral reef metabolism. Sci Rep 2019; 9:12067. [PMID: 31427632 PMCID: PMC6700128 DOI: 10.1038/s41598-019-48407-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 08/05/2019] [Indexed: 12/30/2022] Open
Abstract
The Anthropocene climate has largely been defined by a rapid increase in atmospheric CO2, causing global climate change (warming) and ocean acidification (OA, a reduction in oceanic pH). OA is of particular concern for coral reefs, as the associated reduction in carbonate ion availability impairs biogenic calcification and promotes dissolution of carbonate substrata. While these trends ultimately affect ecosystem calcification, scaling experimental analyses of the response of organisms to OA to consider the response of ecosystems to OA has proved difficult. The benchmark of ecosystem-level experiments to study the effects of OA is provided through Free Ocean CO2 Enrichment (FOCE), which we use in the present analyses for a 21-d experiment on the back reef of Mo’orea, French Polynesia. Two natural coral reef communities were incubated in situ, with one exposed to ambient pCO2 (393 µatm), and one to high pCO2 (949 µatm). Our results show a decrease in 24-h net community calcification (NCC) under high pCO2, and a reduction in nighttime NCC that attenuated and eventually reversed over 21-d. This effect was not observed in daytime NCC, and it occurred without any effect of high pCO2 on net community production (NCP). These results contribute to previous studies on ecosystem-level responses of coral reefs to the OA conditions projected for the end of the century, and they highlight potential attenuation of high pCO2 effects on nighttime net community calcification.
Collapse
|
13
|
In-situ behavioural and physiological responses of Antarctic microphytobenthos to ocean acidification. Sci Rep 2019; 9:1890. [PMID: 30760730 PMCID: PMC6374400 DOI: 10.1038/s41598-018-36233-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 11/06/2018] [Indexed: 02/07/2023] Open
Abstract
Ocean acidification (OA) is predicted to alter benthic marine community structure and function, however, there is a paucity of field experiments in benthic soft sediment communities and ecosystems. Benthic diatoms are important components of Antarctic coastal ecosystems, however very little is known of how they will respond to ocean acidification. Ocean acidification conditions were maintained by incremental computer controlled addition of high fCO2 seawater representing OA conditions predicted for the year 2100. Respiration chambers and PAM fluorescence techniques were used to investigate acute behavioural, photosynthetic and net production responses of benthic microalgae communities to OA in in-situ field experiments. We demonstrate how OA can modify behavioural ecology, which changes photo-physiology and net production of benthic microalgae. Ocean acidification treatments significantly altered behavioural ecology, which in turn altered photo-physiology. The ecological trends presented here have the potential to manifest into significant ecological change over longer time periods.
Collapse
|
14
|
van Oppen MJH, Bongaerts P, Frade P, Peplow L, Boyd SE, Nim HT, Bay LK. Adaptation to reef habitats through selection on the coral animal and its associated microbiome. Mol Ecol 2018; 27:2956-2971. [DOI: 10.1111/mec.14763] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 06/01/2018] [Accepted: 06/04/2018] [Indexed: 01/02/2023]
Affiliation(s)
- Madeleine J. H. van Oppen
- Australian Institute of Marine Science; Townsville MC Qld Australia
- School of BioSciences; University of Melbourne; Parkville Vic. Australia
| | - Pim Bongaerts
- Global Change Institute; The University of Queensland; St Lucia Qld Australia
- California Academy of Sciences; San Francisco California
| | - Pedro Frade
- Centre of Marine Sciences (CCMAR); University of Algarve; Faro Portugal
| | - Lesa M. Peplow
- Australian Institute of Marine Science; Townsville MC Qld Australia
| | - Sarah E. Boyd
- Faculty of Information Technology; Monash University; Melbourne Vic. Australia
| | - Hieu T. Nim
- Faculty of Information Technology; Monash University; Melbourne Vic. Australia
- Australian Regenerative Medicine Institute; Monash University; Melbourne Vic. Australia
| | - Line K. Bay
- Australian Institute of Marine Science; Townsville MC Qld Australia
| |
Collapse
|
15
|
Cross EL, Harper EM, Peck LS. A 120-year record of resilience to environmental change in brachiopods. GLOBAL CHANGE BIOLOGY 2018; 24:2262-2271. [PMID: 29536586 PMCID: PMC6850138 DOI: 10.1111/gcb.14085] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 12/25/2017] [Accepted: 01/17/2018] [Indexed: 06/01/2023]
Abstract
The inability of organisms to cope in changing environments poses a major threat to their survival. Rising carbon dioxide concentrations, recently exceeding 400 μatm, are rapidly warming and acidifying our oceans. Current understanding of organism responses to this environmental phenomenon is based mainly on relatively short- to medium-term laboratory and field experiments, which cannot evaluate the potential for long-term acclimation and adaptation, the processes identified as most important to confer resistance. Here, we present data from a novel approach that assesses responses over a centennial timescale showing remarkable resilience to change in a species predicted to be vulnerable. Utilising museum collections allows the assessment of how organisms have coped with past environmental change. It also provides a historical reference for future climate change responses. We evaluated a unique specimen collection of a single species of brachiopod (Calloria inconspicua) collected every decade from 1900 to 2014 from one sampling site. The majority of brachiopod shell characteristics remained unchanged over the past century. One response, however, appears to reinforce their shell by constructing narrower punctae (shell perforations) and laying down more shell. This study indicates one of the most calcium-carbonate-dependent species globally to be highly resilient to environmental change over the last 120 years and provides a new insight for how similar species might react and possibly adapt to future change.
Collapse
Affiliation(s)
- Emma L. Cross
- Department of Earth SciencesUniversity of CambridgeCambridgeUK
- British Antarctic SurveyNatural Environment Research CouncilCambridgeUK
| | | | - Lloyd S. Peck
- British Antarctic SurveyNatural Environment Research CouncilCambridgeUK
| |
Collapse
|
16
|
Bracken MES, Silbiger NJ, Bernatchez G, Sorte CJB. Primary producers may ameliorate impacts of daytime CO 2 addition in a coastal marine ecosystem. PeerJ 2018; 6:e4739. [PMID: 29761055 PMCID: PMC5949060 DOI: 10.7717/peerj.4739] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Accepted: 04/19/2018] [Indexed: 11/20/2022] Open
Abstract
Predicting the impacts of ocean acidification in coastal habitats is complicated by bio-physical feedbacks between organisms and carbonate chemistry. Daily changes in pH and other carbonate parameters in coastal ecosystems, associated with processes such as photosynthesis and respiration, often greatly exceed global mean predicted changes over the next century. We assessed the strength of these feedbacks under projected elevated CO2 levels by conducting a field experiment in 10 macrophyte-dominated tide pools on the coast of California, USA. We evaluated changes in carbonate parameters over time and found that under ambient conditions, daytime changes in pH, pCO2, net ecosystem calcification (NEC), and O2 concentrations were strongly related to rates of net community production (NCP). CO2 was added to pools during daytime low tides, which should have reduced pH and enhanced pCO2. However, photosynthesis rapidly reduced pCO2 and increased pH, so effects of CO2 addition were not apparent unless we accounted for seaweed and surfgrass abundances. In the absence of macrophytes, CO2 addition caused pH to decline by ∼0.6 units and pCO2 to increase by ∼487 µatm over 6 hr during the daytime low tide. As macrophyte abundances increased, the impacts of CO2 addition declined because more CO2 was absorbed due to photosynthesis. Effects of CO2addition were, therefore, modified by feedbacks between NCP, pH, pCO2, and NEC. Our results underscore the potential importance of coastal macrophytes in ameliorating impacts of ocean acidification.
Collapse
Affiliation(s)
- Matthew E S Bracken
- Department of Ecology and Evolutionary Biology, University of California, Irvine, Irvine, CA, United States of America
| | - Nyssa J Silbiger
- Department of Ecology and Evolutionary Biology, University of California, Irvine, Irvine, CA, United States of America.,Department of Biology, California State University, Northridge, Northridge, CA, United States of America
| | - Genevieve Bernatchez
- Department of Ecology and Evolutionary Biology, University of California, Irvine, Irvine, CA, United States of America
| | - Cascade J B Sorte
- Department of Ecology and Evolutionary Biology, University of California, Irvine, Irvine, CA, United States of America
| |
Collapse
|
17
|
|
18
|
Carbonate chemistry of an in-situ free-ocean CO 2 enrichment experiment (antFOCE) in comparison to short term variation in Antarctic coastal waters. Sci Rep 2018; 8:2816. [PMID: 29434330 PMCID: PMC5809532 DOI: 10.1038/s41598-018-21029-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 01/29/2018] [Indexed: 11/08/2022] Open
Abstract
Free-ocean CO2 enrichment (FOCE) experiments have been deployed in marine ecosystems to manipulate carbonate system conditions to those predicted in future oceans. We investigated whether the pH/carbonate chemistry of extremely cold polar waters can be manipulated in an ecologically relevant way, to represent conditions under future atmospheric CO2 levels, in an in-situ FOCE experiment in Antarctica. We examined spatial and temporal variation in local ambient carbonate chemistry at hourly intervals at two sites between December and February and compared these with experimental conditions. We successfully maintained a mean pH offset in acidified benthic chambers of -0.38 (±0.07) from ambient for approximately 8 weeks. Local diel and seasonal fluctuations in ambient pH were duplicated in the FOCE system. Large temporal variability in acidified chambers resulted from system stoppages. The mean pH, Ωarag and fCO2 values in the acidified chambers were 7.688 ± 0.079, 0.62 ± 0.13 and 912 ± 150 µatm, respectively. Variation in ambient pH appeared to be mainly driven by salinity and biological production and ranged from 8.019 to 8.192 with significant spatio-temporal variation. This experiment demonstrates the utility of FOCE systems to create conditions expected in future oceans that represent ecologically relevant variation, even under polar conditions.
Collapse
|
19
|
Campbell JE, Fourqurean JW. Does Nutrient Availability Regulate Seagrass Response to Elevated CO2? Ecosystems 2017. [DOI: 10.1007/s10021-017-0212-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
20
|
Ghedini G, Connell SD. Moving ocean acidification research beyond a simple science: Investigating ecological change and their stabilizers. FOOD WEBS 2017. [DOI: 10.1016/j.fooweb.2017.03.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
21
|
Bruintjes R, Harding HR, Bunce T, Birch F, Lister J, Spiga I, Benson T, Rossington K, Jones D, Tyler CR, Radford AN, Simpson SD. Shipbuilding Docks as Experimental Systems for Realistic Assessments of Anthropogenic Stressors on Marine Organisms. Bioscience 2017; 67:853-859. [PMID: 29599545 PMCID: PMC5862249 DOI: 10.1093/biosci/bix092] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Empirical investigations of the impacts of anthropogenic stressors on marine organisms are typically performed under controlled laboratory conditions, onshore mesocosms, or via offshore experiments with realistic (but uncontrolled) environmental variation. These approaches have merits, but onshore setups are generally small sized and fail to recreate natural stressor fields, whereas offshore studies are often compromised by confounding factors. We suggest the use of flooded shipbuilding docks to allow studying realistic exposure to stressors and their impacts on the intra- and interspecific responses of animals. Shipbuilding docks permit the careful study of groups of known animals, including the evaluation of their behavioral interactions, while enabling full control of the stressor and many environmental conditions. We propose that this approach could be used for assessing the impacts of prominent anthropogenic stressors, including chemicals, ocean warming, and sound. Results from shipbuilding-dock studies could allow improved parameterization of predictive models relating to the environmental risks and population consequences of anthropogenic stressors.
Collapse
Affiliation(s)
- Rick Bruintjes
- Rick Bruintjes , Fiona Birch, Jessica Lister, Charles R. Tyler, and Stephen D. Simpson are affiliated with the Department of Biosciences in the College of Life and Environmental Sciences at the University of Exeter, in the United Kingdom. RB, Tom Benson, Kate Rossington, and Diane Jones are affiliated with HR Wallingford, in Wallingford, United Kingdom. Harry R. Harding, Tom Bunce, and Andrew N. Radford are with the School of Biological Science at the University of Bristol, in the United Kingdom; HRH is also affiliated with Marine Scotland, in Aberdeen, United Kingdom. Ilaria Spiga is with the School of Marine Science and Technology at the University of Newcastle, in the United Kingdom
| | - Harry R Harding
- Rick Bruintjes , Fiona Birch, Jessica Lister, Charles R. Tyler, and Stephen D. Simpson are affiliated with the Department of Biosciences in the College of Life and Environmental Sciences at the University of Exeter, in the United Kingdom. RB, Tom Benson, Kate Rossington, and Diane Jones are affiliated with HR Wallingford, in Wallingford, United Kingdom. Harry R. Harding, Tom Bunce, and Andrew N. Radford are with the School of Biological Science at the University of Bristol, in the United Kingdom; HRH is also affiliated with Marine Scotland, in Aberdeen, United Kingdom. Ilaria Spiga is with the School of Marine Science and Technology at the University of Newcastle, in the United Kingdom
| | - Tom Bunce
- Rick Bruintjes , Fiona Birch, Jessica Lister, Charles R. Tyler, and Stephen D. Simpson are affiliated with the Department of Biosciences in the College of Life and Environmental Sciences at the University of Exeter, in the United Kingdom. RB, Tom Benson, Kate Rossington, and Diane Jones are affiliated with HR Wallingford, in Wallingford, United Kingdom. Harry R. Harding, Tom Bunce, and Andrew N. Radford are with the School of Biological Science at the University of Bristol, in the United Kingdom; HRH is also affiliated with Marine Scotland, in Aberdeen, United Kingdom. Ilaria Spiga is with the School of Marine Science and Technology at the University of Newcastle, in the United Kingdom
| | - Fiona Birch
- Rick Bruintjes , Fiona Birch, Jessica Lister, Charles R. Tyler, and Stephen D. Simpson are affiliated with the Department of Biosciences in the College of Life and Environmental Sciences at the University of Exeter, in the United Kingdom. RB, Tom Benson, Kate Rossington, and Diane Jones are affiliated with HR Wallingford, in Wallingford, United Kingdom. Harry R. Harding, Tom Bunce, and Andrew N. Radford are with the School of Biological Science at the University of Bristol, in the United Kingdom; HRH is also affiliated with Marine Scotland, in Aberdeen, United Kingdom. Ilaria Spiga is with the School of Marine Science and Technology at the University of Newcastle, in the United Kingdom
| | - Jessica Lister
- Rick Bruintjes , Fiona Birch, Jessica Lister, Charles R. Tyler, and Stephen D. Simpson are affiliated with the Department of Biosciences in the College of Life and Environmental Sciences at the University of Exeter, in the United Kingdom. RB, Tom Benson, Kate Rossington, and Diane Jones are affiliated with HR Wallingford, in Wallingford, United Kingdom. Harry R. Harding, Tom Bunce, and Andrew N. Radford are with the School of Biological Science at the University of Bristol, in the United Kingdom; HRH is also affiliated with Marine Scotland, in Aberdeen, United Kingdom. Ilaria Spiga is with the School of Marine Science and Technology at the University of Newcastle, in the United Kingdom
| | - Ilaria Spiga
- Rick Bruintjes , Fiona Birch, Jessica Lister, Charles R. Tyler, and Stephen D. Simpson are affiliated with the Department of Biosciences in the College of Life and Environmental Sciences at the University of Exeter, in the United Kingdom. RB, Tom Benson, Kate Rossington, and Diane Jones are affiliated with HR Wallingford, in Wallingford, United Kingdom. Harry R. Harding, Tom Bunce, and Andrew N. Radford are with the School of Biological Science at the University of Bristol, in the United Kingdom; HRH is also affiliated with Marine Scotland, in Aberdeen, United Kingdom. Ilaria Spiga is with the School of Marine Science and Technology at the University of Newcastle, in the United Kingdom
| | - Tom Benson
- Rick Bruintjes , Fiona Birch, Jessica Lister, Charles R. Tyler, and Stephen D. Simpson are affiliated with the Department of Biosciences in the College of Life and Environmental Sciences at the University of Exeter, in the United Kingdom. RB, Tom Benson, Kate Rossington, and Diane Jones are affiliated with HR Wallingford, in Wallingford, United Kingdom. Harry R. Harding, Tom Bunce, and Andrew N. Radford are with the School of Biological Science at the University of Bristol, in the United Kingdom; HRH is also affiliated with Marine Scotland, in Aberdeen, United Kingdom. Ilaria Spiga is with the School of Marine Science and Technology at the University of Newcastle, in the United Kingdom
| | - Kate Rossington
- Rick Bruintjes , Fiona Birch, Jessica Lister, Charles R. Tyler, and Stephen D. Simpson are affiliated with the Department of Biosciences in the College of Life and Environmental Sciences at the University of Exeter, in the United Kingdom. RB, Tom Benson, Kate Rossington, and Diane Jones are affiliated with HR Wallingford, in Wallingford, United Kingdom. Harry R. Harding, Tom Bunce, and Andrew N. Radford are with the School of Biological Science at the University of Bristol, in the United Kingdom; HRH is also affiliated with Marine Scotland, in Aberdeen, United Kingdom. Ilaria Spiga is with the School of Marine Science and Technology at the University of Newcastle, in the United Kingdom
| | - Diane Jones
- Rick Bruintjes , Fiona Birch, Jessica Lister, Charles R. Tyler, and Stephen D. Simpson are affiliated with the Department of Biosciences in the College of Life and Environmental Sciences at the University of Exeter, in the United Kingdom. RB, Tom Benson, Kate Rossington, and Diane Jones are affiliated with HR Wallingford, in Wallingford, United Kingdom. Harry R. Harding, Tom Bunce, and Andrew N. Radford are with the School of Biological Science at the University of Bristol, in the United Kingdom; HRH is also affiliated with Marine Scotland, in Aberdeen, United Kingdom. Ilaria Spiga is with the School of Marine Science and Technology at the University of Newcastle, in the United Kingdom
| | - Charles R Tyler
- Rick Bruintjes , Fiona Birch, Jessica Lister, Charles R. Tyler, and Stephen D. Simpson are affiliated with the Department of Biosciences in the College of Life and Environmental Sciences at the University of Exeter, in the United Kingdom. RB, Tom Benson, Kate Rossington, and Diane Jones are affiliated with HR Wallingford, in Wallingford, United Kingdom. Harry R. Harding, Tom Bunce, and Andrew N. Radford are with the School of Biological Science at the University of Bristol, in the United Kingdom; HRH is also affiliated with Marine Scotland, in Aberdeen, United Kingdom. Ilaria Spiga is with the School of Marine Science and Technology at the University of Newcastle, in the United Kingdom
| | - Andrew N Radford
- Rick Bruintjes , Fiona Birch, Jessica Lister, Charles R. Tyler, and Stephen D. Simpson are affiliated with the Department of Biosciences in the College of Life and Environmental Sciences at the University of Exeter, in the United Kingdom. RB, Tom Benson, Kate Rossington, and Diane Jones are affiliated with HR Wallingford, in Wallingford, United Kingdom. Harry R. Harding, Tom Bunce, and Andrew N. Radford are with the School of Biological Science at the University of Bristol, in the United Kingdom; HRH is also affiliated with Marine Scotland, in Aberdeen, United Kingdom. Ilaria Spiga is with the School of Marine Science and Technology at the University of Newcastle, in the United Kingdom
| | - Stephen D Simpson
- Rick Bruintjes , Fiona Birch, Jessica Lister, Charles R. Tyler, and Stephen D. Simpson are affiliated with the Department of Biosciences in the College of Life and Environmental Sciences at the University of Exeter, in the United Kingdom. RB, Tom Benson, Kate Rossington, and Diane Jones are affiliated with HR Wallingford, in Wallingford, United Kingdom. Harry R. Harding, Tom Bunce, and Andrew N. Radford are with the School of Biological Science at the University of Bristol, in the United Kingdom; HRH is also affiliated with Marine Scotland, in Aberdeen, United Kingdom. Ilaria Spiga is with the School of Marine Science and Technology at the University of Newcastle, in the United Kingdom
| |
Collapse
|
22
|
How Reliable Is Structure from Motion (SfM) over Time and between Observers? A Case Study Using Coral Reef Bommies. REMOTE SENSING 2017. [DOI: 10.3390/rs9070740] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
23
|
Camp EF, Nitschke MR, Rodolfo-Metalpa R, Houlbreque F, Gardner SG, Smith DJ, Zampighi M, Suggett DJ. Reef-building corals thrive within hot-acidified and deoxygenated waters. Sci Rep 2017; 7:2434. [PMID: 28550297 PMCID: PMC5446402 DOI: 10.1038/s41598-017-02383-y] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 04/27/2017] [Indexed: 11/29/2022] Open
Abstract
Coral reefs are deteriorating under climate change as oceans continue to warm and acidify and thermal anomalies grow in frequency and intensity. In vitro experiments are widely used to forecast reef-building coral health into the future, but often fail to account for the complex ecological and biogeochemical interactions that govern reefs. Consequently, observations from coral communities under naturally occurring extremes have become central for improved predictions of future reef form and function. Here, we present a semi-enclosed lagoon system in New Caledonia characterised by diel fluctuations of hot-deoxygenated water coupled with tidally driven persistently low pH, relative to neighbouring reefs. Coral communities within the lagoon system exhibited high richness (number of species = 20) and cover (24-35% across lagoon sites). Calcification rates for key species (Acropora formosa, Acropora pulchra, Coelastrea aspera and Porites lutea) for populations from the lagoon were equivalent to, or reduced by ca. 30-40% compared to those from the reef. Enhanced coral respiration, alongside high particulate organic content of the lagoon sediment, suggests acclimatisation to this trio of temperature, oxygen and pH changes through heterotrophic plasticity. This semi-enclosed lagoon therefore provides a novel system to understand coral acclimatisation to complex climatic scenarios and may serve as a reservoir of coral populations already resistant to extreme environmental conditions.
Collapse
Affiliation(s)
- Emma F Camp
- Climate Change Cluster, University of Technology Sydney, PO Box 123, Broadway, NSW 2007, Australia
| | - Matthew R Nitschke
- Climate Change Cluster, University of Technology Sydney, PO Box 123, Broadway, NSW 2007, Australia
| | - Riccardo Rodolfo-Metalpa
- Institut de Recherche pour le Développement, Centre IRD de Nouméa, ENTROPIE (UMR250), BP A5, 98848, Nouméa cedex, New Caledonia.
| | - Fanny Houlbreque
- Institut de Recherche pour le Développement, Centre IRD de Nouméa, ENTROPIE (UMR250), BP A5, 98848, Nouméa cedex, New Caledonia
| | - Stephanie G Gardner
- Climate Change Cluster, University of Technology Sydney, PO Box 123, Broadway, NSW 2007, Australia
| | - David J Smith
- School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, UK
| | - Marco Zampighi
- Institut de Recherche pour le Développement, Centre IRD de Nouméa, ENTROPIE (UMR250), BP A5, 98848, Nouméa cedex, New Caledonia
| | - David J Suggett
- Climate Change Cluster, University of Technology Sydney, PO Box 123, Broadway, NSW 2007, Australia
| |
Collapse
|
24
|
Bender-Champ D, Diaz-Pulido G, Dove S. Effects of elevated nutrients and CO 2 emission scenarios on three coral reef macroalgae. HARMFUL ALGAE 2017; 65:40-51. [PMID: 28526118 DOI: 10.1016/j.hal.2017.04.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 03/22/2017] [Accepted: 04/07/2017] [Indexed: 06/07/2023]
Abstract
Coral reef macroalgae are expected to thrive in the future under conditions that are deleterious to the health of reef-building corals. Here we examined how macroalgae would be affected by exposure to future CO2 emission scenarios (pCO2 and temperature), enriched nutrients and combinations of both. The species tested, Laurencia intricata (Rhodophyta), Turbinaria ornata and Chnoospora implexa (both Phaeophyceae), have active carbon-concentrating mechanisms but responded differently to the treatments. L. intricata showed high mortality under nutrient enriched RCP4.5 ("reduced" CO2 emission) and RCP8.5 ("business-as-usual" CO2 emission) and grew best under pre-industrial (PI) conditions, where it could take up carbon using external carbonic anhydrase combined, potentially, with proton extrusion. T. ornata's growth rate showed a trend for reduction under RCP8.5 but was unaffected by nutrient enrichment. In C. implexa, highest growth was observed under PI conditions, but highest net photosynthesis occurred under RCP8.5, suggesting that under RCP8.5, carbon is stored and respired at greater rates while it is directed to growth under PI conditions. None of the species showed growth enhancement under future scenarios, nutrient enrichment or combinations of both. This leads to the conclusion that under such conditions these species are unlikely to pose an increasing threat to coral reefs.
Collapse
Affiliation(s)
- Dorothea Bender-Champ
- School of Biological Sciences & Global Change Institute, University of Queensland, QLD 4072, Australia; ARC Centre for Excellence for Coral Reef Studies, University of Queensland, QLD 4072, Australia.
| | - Guillermo Diaz-Pulido
- School of Biological Sciences & Global Change Institute, University of Queensland, QLD 4072, Australia; ARC Centre for Excellence for Coral Reef Studies, University of Queensland, QLD 4072, Australia; Griffith School of Environment and Australian Rivers Institute, Griffith University, QLD 4111, Australia
| | - Sophie Dove
- School of Biological Sciences & Global Change Institute, University of Queensland, QLD 4072, Australia; ARC Centre for Excellence for Coral Reef Studies, University of Queensland, QLD 4072, Australia
| |
Collapse
|
25
|
Albright R, Anthony KRN, Baird M, Beeden R, Byrne M, Collier C, Dove S, Fabricius K, Hoegh-Guldberg O, Kelly RP, Lough J, Mongin M, Munday PL, Pears RJ, Russell BD, Tilbrook B, Abal E. Ocean acidification: Linking science to management solutions using the Great Barrier Reef as a case study. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2016; 182:641-650. [PMID: 27564868 DOI: 10.1016/j.jenvman.2016.07.038] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 07/10/2016] [Accepted: 07/14/2016] [Indexed: 05/20/2023]
Abstract
Coral reefs are one of the most vulnerable ecosystems to ocean acidification. While our understanding of the potential impacts of ocean acidification on coral reef ecosystems is growing, gaps remain that limit our ability to translate scientific knowledge into management action. To guide solution-based research, we review the current knowledge of ocean acidification impacts on coral reefs alongside management needs and priorities. We use the world's largest continuous reef system, Australia's Great Barrier Reef (GBR), as a case study. We integrate scientific knowledge gained from a variety of approaches (e.g., laboratory studies, field observations, and ecosystem modelling) and scales (e.g., cell, organism, ecosystem) that underpin a systems-level understanding of how ocean acidification is likely to impact the GBR and associated goods and services. We then discuss local and regional management options that may be effective to help mitigate the effects of ocean acidification on the GBR, with likely application to other coral reef systems. We develop a research framework for linking solution-based ocean acidification research to practical management options. The framework assists in identifying effective and cost-efficient options for supporting ecosystem resilience. The framework enables on-the-ground OA management to be the focus, while not losing sight of CO2 mitigation as the ultimate solution.
Collapse
Affiliation(s)
- Rebecca Albright
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia; Carnegie Institution for Science, Department of Global Ecology, Stanford, CA, USA.
| | | | - Mark Baird
- Commonwealth Scientific and Industrial Research Organisation, Oceans and Atmosphere Flagship, Hobart, Australia
| | - Roger Beeden
- Great Barrier Reef Marine Park Authority, PO Box 1379, Townsville, Queensland 4810, Australia
| | - Maria Byrne
- Schools of Medical and Biological Sciences, University of Sydney, Australia
| | - Catherine Collier
- Centre for Tropical Water and Aquatic Ecosystem Research, James Cook University, Cairns, QLD 4870, Australia
| | - Sophie Dove
- Global Change Institute and ARC Centre of Excellence for Coral Reef Studies, The University of Queensland, Brisbane, QLD 4072, Australia
| | | | - Ove Hoegh-Guldberg
- Global Change Institute and ARC Centre of Excellence for Coral Reef Studies, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Ryan P Kelly
- School of Marine and Environmental Affairs, University of Washington, Seattle, WA 98105, USA
| | - Janice Lough
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia; ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia
| | - Mathieu Mongin
- Commonwealth Scientific and Industrial Research Organisation, Oceans and Atmosphere Flagship, Hobart, Australia
| | - Philip L Munday
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia
| | - Rachel J Pears
- Great Barrier Reef Marine Park Authority, PO Box 1379, Townsville, Queensland 4810, Australia
| | - Bayden D Russell
- Swire Institute of Marine Science and School of Biological Sciences, The University of Hong Kong, Hong Kong, SAR, China
| | - Bronte Tilbrook
- Commonwealth Scientific and Industrial Research Organisation, Oceans and Atmosphere Flagship, Hobart, Australia
| | - Eva Abal
- University of Queensland, Brisbane, QLD 4072, Australia
| |
Collapse
|
26
|
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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
27
|
Tollefson J. Ocean acidification reversed on Great Barrier Reef. Nature 2016. [DOI: 10.1038/nature.2016.19410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
28
|
Albright R, Caldeira L, Hosfelt J, Kwiatkowski L, Maclaren JK, Mason BM, Nebuchina Y, Ninokawa A, Pongratz J, Ricke KL, Rivlin T, Schneider K, Sesboüé M, Shamberger K, Silverman J, Wolfe K, Zhu K, Caldeira K. Reversal of ocean acidification enhances net coral reef calcification. Nature 2016; 531:362-5. [DOI: 10.1038/nature17155] [Citation(s) in RCA: 182] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 01/20/2016] [Indexed: 11/09/2022]
|
29
|
Jokiel PL, Jury CP, Kuffner IB. Coral Calcification and Ocean Acidification. CORAL REEFS OF THE WORLD 2016. [DOI: 10.1007/978-94-017-7567-0_2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
|
30
|
Sorte CJB, Bracken MES. Warming and Elevated CO2 Interact to Drive Rapid Shifts in Marine Community Production. PLoS One 2015; 10:e0145191. [PMID: 26714167 PMCID: PMC4694712 DOI: 10.1371/journal.pone.0145191] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2015] [Accepted: 12/01/2015] [Indexed: 11/18/2022] Open
Abstract
Predicting the outcome of future climate change requires an understanding of how alterations in multiple environmental factors manifest in natural communities and affect ecosystem functioning. We conducted an in situ, fully factorial field manipulation of CO2 and temperature on a rocky shoreline in southeastern Alaska, USA. Warming strongly impacted functioning of tide pool systems within one month, with the rate of net community production (NCP) more than doubling in warmed pools under ambient CO2 levels relative to initial NCP values. However, in pools with added CO2, NCP was unaffected by warming. Productivity responses paralleled changes in the carbon-to-nitrogen ratio of a red alga, the most abundant primary producer species in the system, highlighting the direct link between physiology and ecosystem functioning. These observed changes in algal physiology and community productivity in response to our manipulations indicate the potential for natural systems to shift rapidly in response to changing climatic conditions and for multiple environmental factors to act antagonistically.
Collapse
Affiliation(s)
- Cascade J. B. Sorte
- Department of Ecology & Evolutionary Biology, 321 Steinhaus Hall, University of California Irvine, Irvine, California 92697–2525, United States of America
- * E-mail:
| | - Matthew E. S. Bracken
- Department of Ecology & Evolutionary Biology, 321 Steinhaus Hall, University of California Irvine, Irvine, California 92697–2525, United States of America
| |
Collapse
|
31
|
pH homeostasis during coral calcification in a free ocean CO2 enrichment (FOCE) experiment, Heron Island reef flat, Great Barrier Reef. Proc Natl Acad Sci U S A 2015; 112:13219-24. [PMID: 26438833 DOI: 10.1073/pnas.1505586112] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Geochemical analyses (δ(11)B and Sr/Ca) are reported for the coral Porites cylindrica grown within a free ocean carbon enrichment (FOCE) experiment, conducted on the Heron Island reef flat (Great Barrier Reef) for a 6-mo period from June to early December 2010. The FOCE experiment was designed to simulate the effects of CO2-driven acidification predicted to occur by the end of this century (scenario RCP4.5) while simultaneously maintaining the exposure of corals to natural variations in their environment under in situ conditions. Analyses of skeletal growth (measured from extension rates and skeletal density) showed no systematic differences between low-pH FOCE treatments (ΔpH = ∼-0.05 to -0.25 units below ambient) and present day controls (ΔpH = 0) for calcification rates or the pH of the calcifying fluid (pHcf); the latter was derived from boron isotopic compositions (δ(11)B) of the coral skeleton. Furthermore, individual nubbins exhibited near constant δ(11)B compositions along their primary apical growth axes (±0.02 pHcf units) regardless of the season or treatment. Thus, under the highly dynamic conditions of the Heron Island reef flat, P. cylindrica up-regulated the pH of its calcifying fluid (pHcf ∼8.4-8.6), with each nubbin having near-constant pHcf values independent of the large natural seasonal fluctuations of the reef flat waters (pH ∼7.7 to ∼8.3) or the superimposed FOCE treatments. This newly discovered phenomenon of pH homeostasis during calcification indicates that coral living in highly dynamic environments exert strong physiological controls on the carbonate chemistry of their calcifying fluid, implying a high degree of resilience to ocean acidification within the investigated ranges.
Collapse
|
32
|
Bender D, Champ CM, Kline D, Diaz-Pulido G, Dove S. Effects of "Reduced" and "Business-As-Usual" CO2 Emission Scenarios on the Algal Territories of the Damselfish Pomacentrus wardi (Pomacentridae). PLoS One 2015; 10:e0131442. [PMID: 26121163 PMCID: PMC4488243 DOI: 10.1371/journal.pone.0131442] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 06/02/2015] [Indexed: 11/19/2022] Open
Abstract
Turf algae are a very important component of coral reefs, featuring high growth and turnover rates, whilst covering large areas of substrate. As food for many organisms, turf algae have an important role in the ecosystem. Farming damselfish can modify the species composition and productivity of such algal assemblages, while defending them against intruders. Like all organisms however, turf algae and damselfishes have the potential to be affected by future changes in seawater (SW) temperature and pCO2. In this study, algal assemblages, in the presence and absence of farming Pomacentrus wardi were exposed to two combinations of SW temperature and pCO2 levels projected for the austral spring of 2100 (the B1 "reduced" and the A1FI "business-as-usual" CO2 emission scenarios) at Heron Island (GBR, Australia). These assemblages were dominated by the presence of red algae and non-epiphytic cyanobacteria, i.e. cyanobacteria that grow attached to the substrate rather than on filamentous algae. The endpoint algal composition was mostly controlled by the presence/absence of farming damselfish, despite a large variability found between the algal assemblages of individual fish. Different scenarios appeared to be responsible for a mild, species specific change in community composition, observable in some brown and green algae, but only in the absence of farming fish. Farming fish appeared unaffected by the conditions to which they were exposed. Algal biomass reductions were found under "reduced" CO2 emission, but not "business-as-usual" scenarios. This suggests that action taken to limit CO2 emissions may, if the majority of algae behave similarly across all seasons, reduce the potential for phase shifts that lead to algal dominated communities. At the same time the availability of food resources to damselfish and other herbivores would be smaller under "reduced" emission scenarios.
Collapse
Affiliation(s)
- Dorothea Bender
- School of Biological Sciences & Global Change Institute, University of Queensland, Queensland, Australia
- ARC Centre for Excellence for Coral Reef Studies, University of Queensland, Queensland, Australia
| | | | - David Kline
- School of Biological Sciences & Global Change Institute, University of Queensland, Queensland, Australia
| | - Guillermo Diaz-Pulido
- School of Biological Sciences & Global Change Institute, University of Queensland, Queensland, Australia
- ARC Centre for Excellence for Coral Reef Studies, University of Queensland, Queensland, Australia
- Griffith School of Environment and Australian Rivers Institute, Griffith University, Queensland, Australia
| | - Sophie Dove
- School of Biological Sciences & Global Change Institute, University of Queensland, Queensland, Australia
- ARC Centre for Excellence for Coral Reef Studies, University of Queensland, Queensland, Australia
| |
Collapse
|
33
|
Kline DI, Teneva L, Hauri C, Schneider K, Miard T, Chai A, Marker M, Dunbar R, Caldeira K, Lazar B, Rivlin T, Mitchell BG, Dove S, Hoegh-Guldberg O. Six Month In Situ High-Resolution Carbonate Chemistry and Temperature Study on a Coral Reef Flat Reveals Asynchronous pH and Temperature Anomalies. PLoS One 2015; 10:e0127648. [PMID: 26039687 PMCID: PMC4454517 DOI: 10.1371/journal.pone.0127648] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 04/17/2015] [Indexed: 11/18/2022] Open
Abstract
Understanding the temporal dynamics of present thermal and pH exposure on coral reefs is crucial for elucidating reef response to future global change. Diel ranges in temperature and carbonate chemistry parameters coupled with seasonal changes in the mean conditions define periods during the year when a reef habitat is exposed to anomalous thermal and/or pH exposure. Anomalous conditions are defined as values that exceed an empirically estimated threshold for each variable. We present a 200-day time series from June through December 2010 of carbonate chemistry and environmental parameters measured on the Heron Island reef flat. These data reveal that aragonite saturation state, pH, and pCO2 were primarily modulated by biologically-driven changes in dissolved organic carbon (DIC) and total alkalinity (TA), rather than salinity and temperature. The largest diel temperature ranges occurred in austral spring, in October (1.5 - 6.6°C) and lowest diel ranges (0.9 - 3.2°C) were observed in July, at the peak of winter. We observed large diel total pH variability, with a maximum range of 7.7 - 8.5 total pH units, with minimum diel average pH values occurring during spring and maximum during fall. As with many other reefs, the nighttime pH minima on the reef flat were far lower than pH values predicted for the open ocean by 2100. DIC and TA both increased from June (end of Fall) to December (end of Spring). Using this high-resolution dataset, we developed exposure metrics of pH and temperature individually for intensity, duration, and severity of low pH and high temperature events, as well as a combined metric. Periods of anomalous temperature and pH exposure were asynchronous on the Heron Island reef flat, which underlines the importance of understanding the dynamics of co-occurrence of multiple stressors on coastal ecosystems.
Collapse
Affiliation(s)
- David I. Kline
- Scripps Institution of Oceanography, Integrative Oceanography Division, University of California San Diego, San Diego, California, United States of America
- Global Change Institute, The University of Queensland, Brisbane, Australia
- Coral Reef Ecosystems Laboratory, School of Biological Sciences, The University of Queensland, Brisbane, Australia
| | - Lida Teneva
- Stanford University, Environmental Earth System Science, Stanford, CA, United States of America
- Conservation International, Betty and Gordon Moore Center for Science and Oceans, Honolulu, HI, 96825, United States of America
| | - Claudine Hauri
- International Pacific Research Centre, University of Hawaii, Honolulu, HI, United States of America
- Institute of Marine Science, School of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, AK, United States of America
| | - Kenneth Schneider
- Stanford University, Environmental Earth System Science, Stanford, CA, United States of America
- Carnegie Institution, Department of Global Ecology, Stanford, CA, United States of America
| | - Thomas Miard
- Coral Reef Ecosystems Laboratory, School of Biological Sciences, The University of Queensland, Brisbane, Australia
- Institut Océanographique Paul Ricard, Ile des Embiez- Le Brusc, 83140, Six-Fours-Les-Plages, France
| | - Aaron Chai
- Coral Reef Ecosystems Laboratory, School of Biological Sciences, The University of Queensland, Brisbane, Australia
| | - Malcolm Marker
- The University of Queensland, Faculty of Engineering, Architecture and Information Technology, Brisbane, Australia
| | - Rob Dunbar
- Stanford University, Environmental Earth System Science, Stanford, CA, United States of America
| | - Ken Caldeira
- Carnegie Institution, Department of Global Ecology, Stanford, CA, United States of America
| | - Boaz Lazar
- The Interuniversity Institute for Marine Sciences, The H. Steinitz Marine Biology Laboratory, The Hebrew University of Jerusalem, Eilat, Israel
| | - Tanya Rivlin
- The Interuniversity Institute for Marine Sciences, The H. Steinitz Marine Biology Laboratory, The Hebrew University of Jerusalem, Eilat, Israel
| | - Brian Gregory Mitchell
- Scripps Institution of Oceanography, Integrative Oceanography Division, University of California San Diego, San Diego, California, United States of America
| | - Sophie Dove
- Global Change Institute, The University of Queensland, Brisbane, Australia
- Coral Reef Ecosystems Laboratory, School of Biological Sciences, The University of Queensland, Brisbane, Australia
- The ARC Centre of Excellence for Coral Reef Studies, The University of Queensland, Brisbane, Australia
| | - Ove Hoegh-Guldberg
- Global Change Institute, The University of Queensland, Brisbane, Australia
- Coral Reef Ecosystems Laboratory, School of Biological Sciences, The University of Queensland, Brisbane, Australia
- The ARC Centre of Excellence for Coral Reef Studies, The University of Queensland, Brisbane, Australia
| |
Collapse
|
34
|
Barry JP, Lovera C, Buck KR, Peltzer ET, Taylor JR, Walz P, Whaling PJ, Brewer PG. Use of a free ocean CO₂ enrichment (FOCE) system to evaluate the effects of ocean acidification on the foraging behavior of a deep-sea urchin. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:9890-9897. [PMID: 25051305 DOI: 10.1021/es501603r] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The influence of ocean acidification in deep-sea ecosystems is poorly understood but is expected to be large because of the presumed low tolerance of deep-sea taxa to environmental change. We used a newly developed deep-sea free ocean CO2 enrichment (dp-FOCE) system to evaluate the potential consequences of future ocean acidification on the feeding behavior of a deep-sea echinoid, the sea urchin, Strongylocentrotus fragilis. The dp-FOCE system simulated future ocean acidification inside an experimental enclosure where observations of feeding behavior were performed. We measured the average movement (speed) of urchins as well as the time required (foraging time) for S. fragilis to approach its preferred food (giant kelp) in the dp-FOCE chamber (-0.46 pH units) and a control chamber (ambient pH). Measurements were performed during each of 4 trials (days -2, 2, 24, 27 after CO2 injection) during the month-long period when groups of urchins were continuously exposed to low pH or control conditions. Although urchin speed did not vary significantly in relation to pH or time exposed, foraging time was significantly longer for urchins in the low-pH treatment. This first deep-sea FOCE experiment demonstrated the utility of the FOCE system approach and suggests that the chemosensory behavior of a deep-sea urchin may be impaired by ocean acidification.
Collapse
Affiliation(s)
- James P Barry
- Monterey Bay Aquarium Research Institute , 7700 Sandholdt Road, Moss Landing, California 95039, United States
| | | | | | | | | | | | | | | |
Collapse
|
35
|
Bresnahan PJ, Martz TR, Takeshita Y, Johnson KS, LaShomb M. Best practices for autonomous measurement of seawater pH with the Honeywell Durafet. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.mio.2014.08.003] [Citation(s) in RCA: 121] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
36
|
Milazzo M, Rodolfo-Metalpa R, Chan VBS, Fine M, Alessi C, Thiyagarajan V, Hall-Spencer JM, Chemello R. Ocean acidification impairs vermetid reef recruitment. Sci Rep 2014; 4:4189. [PMID: 24577050 PMCID: PMC5379440 DOI: 10.1038/srep04189] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Accepted: 01/20/2014] [Indexed: 01/20/2023] Open
Abstract
Vermetids form reefs in sub-tropical and warm-temperate waters that protect coasts from erosion, regulate sediment transport and accumulation, serve as carbon sinks and provide habitat for other species. The gastropods that form these reefs brood encapsulated larvae; they are threatened by rapid environmental changes since their ability to disperse is very limited. We used transplant experiments along a natural CO2 gradient to assess ocean acidification effects on the reef-building gastropod Dendropoma petraeum. We found that although D. petraeum were able to reproduce and brood at elevated levels of CO2, recruitment success was adversely affected. Long-term exposure to acidified conditions predicted for the year 2100 and beyond caused shell dissolution and a significant increase in shell Mg content. Unless CO2 emissions are reduced and conservation measures taken, our results suggest these reefs are in danger of extinction within this century, with significant ecological and socioeconomic ramifications for coastal systems.
Collapse
Affiliation(s)
- Marco Milazzo
- DiSTeM, CoNISMa, University of Palermo, Palermo, Italy
| | - Riccardo Rodolfo-Metalpa
- 1] Marine Biology and Ecology Research Centre, Plymouth University, UK [2] IRD, Unite 227 CoReus2, Noumea, New Caledonia
| | - Vera Bin San Chan
- The Swire Institute of Marine Science and School of Biological Sciences, The University of Hong Kong, Hong Kong SAR
| | - Maoz Fine
- 1] Mina-Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel [2] The interuniversity Institute for Marine Science, Eilat Israel
| | - Cinzia Alessi
- DiSTeM, CoNISMa, University of Palermo, Palermo, Italy
| | - Vengatesen Thiyagarajan
- The Swire Institute of Marine Science and School of Biological Sciences, The University of Hong Kong, Hong Kong SAR
| | | | | |
Collapse
|
37
|
Bender D, Diaz-Pulido G, Dove S. The impact of CO2 emission scenarios and nutrient enrichment on a common coral reef macroalga is modified by temporal effects. JOURNAL OF PHYCOLOGY 2014; 50:203-215. [PMID: 26988019 DOI: 10.1111/jpy.12153] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Accepted: 10/10/2013] [Indexed: 06/05/2023]
Abstract
Future coral reefs are expected to be subject to higher pCO2 and temperature due to anthropogenic greenhouse gas emissions. Such global stressors are often paired with local stressors thereby potentially modifying the response of organisms. Benthic macroalgae are strong competitors to corals and are assumed to do well under future conditions. The present study aimed to assess the impact of past and future CO2 emission scenarios as well as nutrient enrichment on the growth, productivity, pigment, and tissue nutrient content of the common tropical brown alga Chnoospora implexa. Two experiments were conducted to assess the differential impacts of the manipulated conditions in winter and spring. Chnoospora implexa's growth rate averaged over winter and spring declined with increasing pCO2 and temperature. Furthermore, nutrient enrichment did not affect growth. Highest growth was observed under spring pre-industrial (PI) conditions, while slightly reduced growth was observed under winter A1FI ("business-as-usual") scenarios. Productivity was not a good proxy for growth, as net O2 flux increased under A1FI conditions. Nutrient enrichment, whilst not affecting growth, led to luxury nutrient uptake that was greater in winter than in spring. The findings suggest that in contrast with previous work, C. implexa is not likely to show enhanced growth under future conditions in isolation or in conjunction with nutrient enrichment. Instead, the results suggest that greatest growth rates for this species appear to be a feature of the PI past, with A1FI winter conditions leading to potential decreases in the abundance of this species from present day levels.
Collapse
Affiliation(s)
- Dorothea Bender
- School of Biological Sciences, The University of Queensland, St. Lucia, Queensland, 4072, Australia
- ARC Centre of Excellence for Coral Reef Studies, The University of Queensland, St. Lucia, Queensland, 4072, Australia
| | - Guillermo Diaz-Pulido
- Griffith School of Environment & Australian Rivers Institute, Griffith University, Nathan, Queensland, 4111, Australia
| | - Sophie Dove
- School of Biological Sciences, The University of Queensland, St. Lucia, Queensland, 4072, Australia
- ARC Centre of Excellence for Coral Reef Studies, The University of Queensland, St. Lucia, Queensland, 4072, Australia
| |
Collapse
|
38
|
Fang JKH, Mello-Athayde MA, Schönberg CHL, Kline DI, Hoegh-Guldberg O, Dove S. Sponge biomass and bioerosion rates increase under ocean warming and acidification. GLOBAL CHANGE BIOLOGY 2013; 19:3581-3591. [PMID: 23893528 DOI: 10.1111/gcb.12334] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2013] [Revised: 07/12/2013] [Accepted: 07/12/2013] [Indexed: 06/02/2023]
Abstract
The combination of ocean warming and acidification as a result of increasing atmospheric carbon dioxide (CO2 ) is considered to be a significant threat to calcifying organisms and their activities on coral reefs. How these global changes impact the important roles of decalcifying organisms (bioeroders) in the regulation of carbonate budgets, however, is less understood. To address this important question, the effects of a range of past, present and future CO2 emission scenarios (temperature + acidification) on the excavating sponge Cliona orientalis Thiele, 1900 were explored over 12 weeks in early summer on the southern Great Barrier Reef. C. orientalis is a widely distributed bioeroder on many reefs, and hosts symbiotic dinoflagellates of the genus Symbiodinium. Our results showed that biomass production and bioerosion rates of C. orientalis were similar under a pre-industrial scenario and a present day (control) scenario. Symbiodinium population density in the sponge tissue was the highest under the pre-industrial scenario, and decreased towards the two future scenarios with sponge replicates under the 'business-as-usual' CO2 emission scenario exhibiting strong bleaching. Despite these changes, biomass production and the ability of the sponge to erode coral carbonate materials both increased under the future scenarios. Our study suggests that C. orientalis will likely grow faster and have higher bioerosion rates in a high CO2 future than at present, even with significant bleaching. Assuming that our findings hold for excavating sponges in general, increased sponge biomass coupled with accelerated bioerosion may push coral reefs towards net erosion and negative carbonate budgets in the future.
Collapse
Affiliation(s)
- James K H Fang
- Coral Reef Ecosystems Laboratory, School of Biological Sciences, The University of Queensland, St. Lucia, QLD, 4072, Australia; Australian Research Council Centre of Excellence for Coral Reef Studies, The University of Queensland, St. Lucia, QLD, 4072, Australia
| | | | | | | | | | | |
Collapse
|
39
|
Buffer Capacity, Ecosystem Feedbacks, and Seawater Chemistry under Global Change. WATER 2013. [DOI: 10.3390/w5031303] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
40
|
Future reef decalcification under a business-as-usual CO2 emission scenario. Proc Natl Acad Sci U S A 2013; 110:15342-7. [PMID: 24003127 DOI: 10.1073/pnas.1302701110] [Citation(s) in RCA: 127] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Increasing atmospheric partial pressure of CO2 (pCO2) is a major threat to coral reefs, but some argue that the threat is mitigated by factors such as the variability in the response of coral calcification to acidification, differences in bleaching susceptibility, and the potential for rapid adaptation to anthropogenic warming. However the evidence for these mitigating factors tends to involve experimental studies on corals, as opposed to coral reefs, and rarely includes the influence of multiple variables (e.g., temperature and acidification) within regimes that include diurnal and seasonal variability. Here, we demonstrate that the inclusion of all these factors results in the decalcification of patch-reefs under business-as-usual scenarios and reduced, although positive, calcification under reduced-emission scenarios. Primary productivity was found to remain constant across all scenarios, despite significant bleaching and coral mortality under both future scenarios. Daylight calcification decreased and nocturnal decalcification increased sharply from the preindustrial and control conditions to the future scenarios of low (reduced emissions) and high (business-as-usual) increases in pCO2. These changes coincided with deeply negative carbonate budgets, a shift toward smaller carbonate sediments, and an increase in the abundance of sediment microbes under the business-as-usual emission scenario. Experimental coral reefs demonstrated highest net calcification rates and lowest rates of coral mortality under preindustrial conditions, suggesting that reef processes may not have been able to keep pace with the relatively minor environmental changes that have occurred during the last century. Taken together, our results have serious implications for the future of coral reefs under business-as-usual environmental changes projected for the coming decades and century.
Collapse
|
41
|
Connell SD, Kroeker KJ, Fabricius KE, Kline DI, Russell BD. The other ocean acidification problem: CO2 as a resource among competitors for ecosystem dominance. Philos Trans R Soc Lond B Biol Sci 2013; 368:20120442. [PMID: 23980244 PMCID: PMC3758175 DOI: 10.1098/rstb.2012.0442] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Predictions concerning the consequences of the oceanic uptake of increasing atmospheric carbon dioxide (CO2) have been primarily occupied with the effects of ocean acidification on calcifying organisms, particularly those critical to the formation of habitats (e.g. coral reefs) or their maintenance (e.g. grazing echinoderms). This focus overlooks direct and indirect effects of CO2 on non-calcareous taxa that play critical roles in ecosystem shifts (e.g. competitors). We present the model that future atmospheric [CO2] may act as a resource for mat-forming algae, a diverse and widespread group known to reduce the resilience of kelp forests and coral reefs. We test this hypothesis by combining laboratory and field CO2 experiments and data from 'natural' volcanic CO2 vents. We show that mats have enhanced productivity in experiments and more expansive covers in situ under projected near-future CO2 conditions both in temperate and tropical conditions. The benefits of CO2 are likely to vary among species of producers, potentially leading to shifts in species dominance in a high CO2 world. We explore how ocean acidification combines with other environmental changes across a number of scales, and raise awareness of CO2 as a resource whose change in availability could have wide-ranging community consequences beyond its direct effects.
Collapse
Affiliation(s)
- Sean D Connell
- Southern Seas Ecology Laboratories, DP418, School of Earth and Environmental Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia.
| | | | | | | | | |
Collapse
|
42
|
Noisette F, Duong G, Six C, Davoult D, Martin S. Effects of elevated pCO2 on the metabolism of a temperate rhodolith Lithothamnion corallioides grown under different temperatures. JOURNAL OF PHYCOLOGY 2013; 49:746-757. [PMID: 27007207 DOI: 10.1111/jpy.12085] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 05/08/2013] [Indexed: 06/05/2023]
Abstract
Coralline algae are considered among the most sensitive species to near future ocean acidification. We tested the effects of elevated pCO2 on the metabolism of the free-living coralline alga Lithothamnion corallioides ("maerl") and the interactions with changes in temperature. Specimens were collected in North Brittany (France) and grown for 3 months at pCO2 of 380 (ambient pCO2 ), 550, 750, and 1000 μatm (elevated pCO2 ) and at successive temperatures of 10°C (ambient temperature in winter), 16°C (ambient temperature in summer), and 19°C (ambient temperature in summer +3°C). At each temperature, gross primary production, respiration (oxygen flux), and calcification (alkalinity flux) rates were assessed in the light and dark. Pigments were determined by HPLC. Chl a, carotene, and zeaxanthin were the three major pigments found in L. corallioides thalli. Elevated pCO2 did not affect pigment content while temperature slightly decreased zeaxanthin and carotene content at 10°C. Gross production was not affected by temperature but was significantly affected by pCO2 with an increase between 380 and 550 μatm. Light, dark, and diel (24 h) calcification rates strongly decreased with increasing pCO2 regardless of the temperature. Although elevated pCO2 only slightly affected gross production in L. corallioides, diel net calcification was reduced by up to 80% under the 1,000 μatm treatment. Our findings suggested that near future levels of CO2 will have profound consequences for carbon and carbonate budgets in rhodolith beds and for the sustainability of these habitats.
Collapse
Affiliation(s)
- Fanny Noisette
- UPMC Univ. Paris 6, CNRS, UMR 7144, Station Biologique de Roscoff, Place Georges Teissier, Roscoff Cedex, 29688, France
| | - Gwendoline Duong
- UPMC Univ. Paris 6, CNRS, UMR 7144, Station Biologique de Roscoff, Place Georges Teissier, Roscoff Cedex, 29688, France
| | - Christophe Six
- UPMC Univ. Paris 6, CNRS, UMR 7144, Station Biologique de Roscoff, Place Georges Teissier, Roscoff Cedex, 29688, France
| | - Dominique Davoult
- UPMC Univ. Paris 6, CNRS, UMR 7144, Station Biologique de Roscoff, Place Georges Teissier, Roscoff Cedex, 29688, France
| | - Sophie Martin
- UPMC Univ. Paris 6, CNRS, UMR 7144, Station Biologique de Roscoff, Place Georges Teissier, Roscoff Cedex, 29688, France
| |
Collapse
|
43
|
Hakonen A, Anderson LG, Engelbrektsson J, Hulth S, Karlson B. A potential tool for high-resolution monitoring of ocean acidification. Anal Chim Acta 2013; 786:1-7. [DOI: 10.1016/j.aca.2013.04.040] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2013] [Revised: 04/08/2013] [Accepted: 04/11/2013] [Indexed: 10/26/2022]
|
44
|
Ramos-Silva P, Kaandorp J, Huisman L, Marie B, Zanella-Cléon I, Guichard N, Miller DJ, Marin F. The skeletal proteome of the coral Acropora millepora: the evolution of calcification by co-option and domain shuffling. Mol Biol Evol 2013; 30:2099-112. [PMID: 23765379 PMCID: PMC3748352 DOI: 10.1093/molbev/mst109] [Citation(s) in RCA: 116] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
In corals, biocalcification is a major function that may be drastically affected by ocean acidification (OA). Scleractinian corals grow by building up aragonitic exoskeletons that provide support and protection for soft tissues. Although this process has been extensively studied, the molecular basis of biocalcification is poorly understood. Notably lacking is a comprehensive catalog of the skeleton-occluded proteins—the skeletal organic matrix proteins (SOMPs) that are thought to regulate the mineral deposition. Using a combination of proteomics and transcriptomics, we report the first survey of such proteins in the staghorn coral Acropora millepora. The organic matrix (OM) extracted from the coral skeleton was analyzed by mass spectrometry and bioinformatics, enabling the identification of 36 SOMPs. These results provide novel insights into the molecular basis of coral calcification and the macroevolution of metazoan calcifying systems, whereas establishing a platform for studying the impact of OA at molecular level. Besides secreted proteins, extracellular regions of transmembrane proteins are also present, suggesting a close control of aragonite deposition by the calicoblastic epithelium. In addition to the expected SOMPs (Asp/Glu-rich, galaxins), the skeletal repertoire included several proteins containing known extracellular matrix domains. From an evolutionary perspective, the number of coral-specific proteins is low, many SOMPs having counterparts in the noncalcifying cnidarians. Extending the comparison with the skeletal OM proteomes of other metazoans allowed the identification of a pool of functional domains shared between phyla. These data suggest that co-option and domain shuffling may be general mechanisms by which the trait of calcification has evolved.
Collapse
Affiliation(s)
- Paula Ramos-Silva
- UMR 6282 CNRS, Biogéosciences, Université de Bourgogne, Dijon, France
| | | | | | | | | | | | | | | |
Collapse
|
45
|
Shaw EC, McNeil BI, Tilbrook B, Matear R, Bates ML. Anthropogenic changes to seawater buffer capacity combined with natural reef metabolism induce extreme future coral reef CO2 conditions. GLOBAL CHANGE BIOLOGY 2013; 19:1632-41. [PMID: 23505026 DOI: 10.1111/gcb.12154] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 01/16/2013] [Accepted: 01/18/2013] [Indexed: 05/20/2023]
Abstract
Ocean acidification, via an anthropogenic increase in seawater carbon dioxide (CO2 ), is potentially a major threat to coral reefs and other marine ecosystems. However, our understanding of how natural short-term diurnal CO2 variability in coral reefs influences longer term anthropogenic ocean acidification remains unclear. Here, we combine observed natural carbonate chemistry variability with future carbonate chemistry predictions for a coral reef flat in the Great Barrier Reef based on the RCP8.5 CO2 emissions scenario. Rather than observing a linear increase in reef flat partial pressure of CO2 (pCO2 ) in concert with rising atmospheric concentrations, the inclusion of in situ diurnal variability results in a highly nonlinear threefold amplification of the pCO2 signal by the end of the century. This significant nonlinear amplification of diurnal pCO2 variability occurs as a result of combining natural diurnal biological CO2 metabolism with long-term decreases in seawater buffer capacity, which occurs via increasing anthropogenic CO2 absorption by the ocean. Under the same benthic community composition, the amplification in the variability in pCO2 is likely to lead to exposure to mean maximum daily pCO2 levels of ca. 2100 μatm, with corrosive conditions with respect to aragonite by end-century at our study site. Minimum pCO2 levels will become lower relative to the mean offshore value (ca. threefold increase in the difference between offshore and minimum reef flat pCO2 ) by end-century, leading to a further increase in the pCO2 range that organisms are exposed to. The biological consequences of short-term exposure to these extreme CO2 conditions, coupled with elevated long-term mean CO2 conditions are currently unknown and future laboratory experiments will need to incorporate natural variability to test this. The amplification of pCO2 that we describe here is not unique to our study location, but will occur in all shallow coastal environments where high biological productivity drives large natural variability in carbonate chemistry.
Collapse
Affiliation(s)
- Emily C Shaw
- Climate Change Research Centre, The University of New South Wales, Sydney, NSW, Australia.
| | | | | | | | | |
Collapse
|
46
|
Marine Ecosystems, Biogeochemistry, and Climate. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/b978-0-12-391851-2.00031-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
|