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Alaska Ocean Acidification Network: State of the Science Workshop, 30 November – 1 December 2016, Anchorage, Alaska

Published 11 November 2016 Courses and training Closed

Registration deadline: 14 November 2016!

Dates: 30 November 2016 – 1 December 2016

Location: Downtown Marriott, Anchorage, Alaska

Description: The Alaska Ocean Acidification Network is hosting a 2-day workshop in Anchorage, inviting a broad audience across the state interested in ocean acidification issues.

The aim of this workshop is to educate the broader Alaska community on the processes and consequences of OA, create connections between researchers and stakeholders, and develop new ideas and partnerships to enhance monitoring and community engagement. A report on the state of the science in Alaska will be produced after the workshop, as well as a set of recommendations to help guide the Alaska OA Network.

Day 1 will be conducted in plenary format and is intended to engage a broad audience including fishermen, shellfish growers, resource managers, researchers, coastal residents and anyone interested in ocean acidification. This first day will provide the basics on OA and an overview of research, monitoring, trends, forecasts and strategies for adaptation. Day 2 will be more discussion-oriented and include breakout groups, a session for OA researchers, and a meeting of the Alaska OA Network steering committee.

This workshop is free and open to the public. Please register by Nov 14.

Agenda and further information.

New HeroX Big Ocean Button Challenge seeks data apps to turn vast amounts of ocean data into useful products and services

Published 11 November 2016 Press releases Closed

Crowdsourcing Competition to Award $100,000 for Big Ocean Mobile App Innovations.

LOS ANGELES, CA–(Marketwired – November 10, 2016) – HeroX today launched the Big Ocean Button Challenge — a crowdsourcing competition to find breakthroughs that transform big ocean data into useful mobile applications. Sponsored by XPRIZE and a follow-on to the Wendy Schmidt Ocean Health XPRIZE, the Big Ocean Button Challenge announced at BlueTech Week in San Diego hosted by the Maritime Alliance, utilizes the HeroX Challenge Platform to seek new solutions for organizing and broadcasting ocean data with application innovations in five categories: Fishing, Shipping and Trade, Ocean Acidification, Public Safety and Exploration.

“Terabytes of data are collected everyday by the ocean community, but only a small fraction are shared with the public through useful apps and services,” said Matt Mulrennan, manager of XPRIZE’s Ocean Initiative. “With billions of people around the world relying on ocean resources from seafood to shipping to recreation, unlocking this wealth of data to catalyze a multibillion-dollar blue economy in ocean data products and services will radically transform how we connect with and protect our precious seas.” (…)

Continue reading ‘New HeroX Big Ocean Button Challenge seeks data apps to turn vast amounts of ocean data into useful products and services’

Sea hare Aplysia punctata (Mollusca: Gastropoda) can maintain shell calcification under extreme ocean acidification

Published 11 November 2016 Science Closed
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Ocean acidification is expected to cause energetic constraints upon marine calcifying organisms such as molluscs and echinoderms, because of the increased costs of building or maintaining shell material in lower pH. We examined metabolic rate, shell morphometry, and calcification in the sea hare Aplysia punctata under short-term exposure (19 days) to an extreme ocean acidification scenario (pH 7.3, ∼2800 μatm pCO2), along with a group held in control conditions (pH 8.1, ∼344 μatm pCO2). This gastropod and its congeners are broadly distributed and locally abundant grazers, and have an internal shell that protects the internal organs. Specimens were examined for metabolic rate via closed-chamber respirometry, followed by removal and examination of the shell under confocal microscopy. Staining using calcein determined the amount of new calcification that occurred over 6 days at the end of the acclimation period. The width of new, pre-calcified shell on the distal shell margin was also quantified as a proxy for overall shell growth. Aplysia punctata showed a 30% reduction in metabolic rate under low pH, but calcification was not affected. This species is apparently able to maintain calcification rate even under extreme low pH, and even when under the energetic constraints of lower metabolism. This finding adds to the evidence that calcification is a largely autonomous process of crystallization that occurs as long as suitable haeomocoel conditions are preserved. There was, however, evidence that the accretion of new, noncalcified shell material may have been reduced, which would lead to overall reduced shell growth under longer-term exposures to low pH independent of calcification. Our findings highlight that the chief impact of ocean acidification upon the ability of marine invertebrates to maintain their shell under low pH may be energetic constraints that hinder growth of supporting structure, rather than maintenance of calcification.

Continue reading ‘Sea hare Aplysia punctata (Mollusca: Gastropoda) can maintain shell calcification under extreme ocean acidification’

Size-dependent response of foraminiferal calcification to seawater carbonate chemistry

Published 10 November 2016 Science Closed
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The response of the marine carbon cycle to changes in atmospheric CO2 concentrations will be determined, in part, by the relative response of calcifying and non-calcifying organisms to global change. Planktonic foraminifera are responsible for a quarter or more of global carbonate production, therefore understanding the sensitivity of calcification in these organisms to environmental change is critical. Despite this, there remains little consensus as to whether, or to what extent, chemical and physical factors affect foraminiferal calcification. To address this, we directly test the effect of multiple controls on calcification in culture experiments and core-top measurements of Globigerinoides ruber. We find that two factors, body size and the carbonate system, strongly influence calcification intensity in life, but that exposure to corrosive bottom waters can overprint this signal post mortem. Using a simple model for the addition of calcite through ontogeny, we show that variable body size between and within datasets could complicate studies that examine environmental controls on foraminiferal shell weight. In addition, we suggest that size could ultimately play a role in determining whether calcification will increase or decrease with acidification. Our models highlight that knowledge of the specific morphological and physiological mechanisms driving ontogenetic change in calcification in different species will be critical in predicting the response of foraminiferal calcification to future change in atmospheric pCO2.

Continue reading ‘Size-dependent response of foraminiferal calcification to seawater carbonate chemistry’

Rising CO2 threatens coral and people who use reefs

Published 10 November 2016 Science Closed

ospreyreef_jaynejenkinsAs atmospheric carbon dioxide (CO2) levels rise, very few coral reef ecosystems will be spared the impacts of ocean acidification or sea surface temperature rise, according to a new analysis. The damage will cause the most immediate and serious threats where human dependence on reefs is highest.

A new analysis in the journal Plos One, led by Duke University and the Université de Bretagne Occidentale, suggests that by 2050, Western Mexico, Micronesia, Indonesia, parts of Australia and Southeast Asia will bear the brunt of rising temperatures. Reef damage will result in lost fish habitats and shoreline protection, jeopardizing the lives and economic prosperity of people who depend on reefs for tourism and food.

Continue reading ‘Rising CO2 threatens coral and people who use reefs’

Coral reefs and people in a high-CO2 world: where can science make a difference to people?

Published 10 November 2016 Science Closed
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Reefs and People at Risk

Increasing levels of carbon dioxide in the atmosphere put shallow, warm-water coral reef ecosystems, and the people who depend upon them at risk from two key global environmental stresses: 1) elevated sea surface temperature (that can cause coral bleaching and related mortality), and 2) ocean acidification. These global stressors: cannot be avoided by local management, compound local stressors, and hasten the loss of ecosystem services. Impacts to people will be most grave where a) human dependence on coral reef ecosystems is high, b) sea surface temperature reaches critical levels soonest, and c) ocean acidification levels are most severe. Where these elements align, swift action will be needed to protect people’s lives and livelihoods, but such action must be informed by data and science.

An Indicator Approach

Designing policies to offset potential harm to coral reef ecosystems and people requires a better understanding of where CO2-related global environmental stresses could cause the most severe impacts. Mapping indicators has been proposed as a way of combining natural and social science data to identify policy actions even when the needed science is relatively nascent. To identify where people are at risk and where more science is needed, we map indicators of biological, physical and social science factors to understand how human dependence on coral reef ecosystems will be affected by globally-driven threats to corals expected in a high-CO2 world. Western Mexico, Micronesia, Indonesia and parts of Australia have high human dependence and will likely face severe combined threats. As a region, Southeast Asia is particularly at risk. Many of the countries most dependent upon coral reef ecosystems are places for which we have the least robust data on ocean acidification. These areas require new data and interdisciplinary scientific research to help coral reef-dependent human communities better prepare for a high CO2 world.

Continue reading ‘Coral reefs and people in a high-CO2 world: where can science make a difference to people?’

Increased temperature, rather than elevated CO2, modulates the carbon assimilation of the Arctic kelps Saccharina latissima and Laminaria solidungula

Published 10 November 2016 Science Closed
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Ocean acidification and warming are affecting with special intensity the Arctic Ocean. Arctic coastal ecosystems are dominated by kelp forests with a high biomass production, which are expected to be directly affected by the increases in CO2 and temperature. This study presents the different physiological responses of the Arctic kelps Saccharina latissima and Laminaria solidungula from Kongsfjorden (Svalbard) cultured at 4 and 9 °C in combination with current (390 ppm) and increased (1200 ppm) levels of atmospheric CO2. Both species were largely unaffected by increased CO2 conditions. Carbon fixation was not influenced by CO2, indicating that photosynthesis was C-saturated at present levels, and 13C isotopic discrimination values from algal tissue suggested no deactivation of carbon concentrating mechanisms at increased CO2 levels. Inhibition of photosynthesis by carbonic anhydrases (CAs) inhibitors highlighted the important role of external CAs in inorganic carbon acquisition in Arctic kelps. Saccharina latissima showed a significantly higher growth rate at 9 °C than at 4 °C, probably due to the decrease in the dark respiration rate observed. Growth rate of L. solidungula was not affected by temperature or CO2, and increases in photosynthesis at 9 °C could be partially related to a higher dissolved organic carbon release rate. The photochemical performance of both species was not altered by any of the treatments. These results suggest that S. latissima might be more benefited than L. solidungula in a future warmer Arctic, while both populations seem to be resilient to higher CO2 concentrations.

Continue reading ‘Increased temperature, rather than elevated CO2, modulates the carbon assimilation of the Arctic kelps Saccharina latissima and Laminaria solidungula’

An abyssal carbonate compensation depth overshoot in the aftermath of the Palaeocene–Eocene Thermal Maximum

Published 9 November 2016 Science Closed
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During the Palaeocene–Eocene Thermal Maximum (PETM) about 56 million years ago, thousands of petagrams of carbon were released into the atmosphere and ocean in just a few thousand years, followed by gradual sequestration over approximately 200,000 years. If silicate weathering is one of the key negative feedbacks that removed this carbon, a period of seawater calcium carbonate saturation greater than pre-event levels would be expected during the event’s recovery phase. In marine sediments, this should be recorded as a temporary deepening of the depth below which no calcite is preserved — the calcite compensation depth (CCD). Previous and new sedimentary records from sites that were above the pre-PETM CCD show enhanced carbonate accumulation following the PETM. A new record from an abyssal site in the North Atlantic that lay below the pre-PETM CCD shows a period of carbonate preservation beginning about 70,000 years after the onset of the PETM, providing the first direct evidence for an over-deepening of the CCD. This record confirms an overshoot in ocean carbonate saturation during the PETM recovery. Simulations with two earth system models support scenarios for the PETM that involve a large initial carbon release followed by prolonged low-level emissions, consistent with the timing of CCD deepening in our record. Our findings indicate that sequestration of these carbon emissions was most likely the result of both globally enhanced calcite burial above the CCD and, at least in the North Atlantic, an over-deepening of the CCD.

Continue reading ‘An abyssal carbonate compensation depth overshoot in the aftermath of the Palaeocene–Eocene Thermal Maximum’

Near-future ocean acidification enhances the feeding rate and development of the herbivorous juveniles of the crown-of-thorns starfish, Acanthaster planci

Published 9 November 2016 Science Closed
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Population outbreaks of the corallivorous crown-of-thorns starfish, Acanthaster planci, are a major contributor to the decline in coral reef across the Indo-Pacific. The success of A. planci and other reef species in a changing ocean will be influenced by juvenile performance because the naturally high mortality experienced at this sensitive life history stage maybe exacerbated by ocean warming and acidification. We investigated the effects of increased temperature and acidification on growth of newly metamorphosed juvenile A. planci and their feeding rates on crustose coralline algae (CCA) during the initial herbivorous phase of their life history. The juveniles were exposed to three temperature (26, 28, 30 °C) and three pH (NIST scale: 8.1, 7.8, 7.6) levels in a flow-through cross-factorial experiment. There were positive but independent effects of warming and acidification on juvenile growth and feeding. Early juveniles were highly tolerant to moderate increases in temperature (+2 °C above ambient) with the highest growth at 30 °C. Growth and feeding rates of A. planci on CCA were highest at pH 7.6. Thus, ocean warming and acidification may enhance the success of A. planci juveniles. In contrast to its coral prey, at this vulnerable developmental stage, A. planci appears to be highly resilient to future ocean change. Success of juveniles in a future ocean may have carry-over effects into the coral-eating life stage, increasing the threat to coral reef systems.

Continue reading ‘Near-future ocean acidification enhances the feeding rate and development of the herbivorous juveniles of the crown-of-thorns starfish, Acanthaster planci’

H+-driven increase in CO2 uptake and decrease in inline image uptake explain coccolithophores’ acclimation responses to ocean acidification

Published 9 November 2016 Science Closed
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Recent ocean acidification (OA) studies revealed that seawater [H+] rather than [CO2] or [ inline image] regulate short-term responses in carbon fluxes of Emiliania huxleyi. Here, we investigated whether acclimation to altered carbonate chemistry modulates this regulation pattern and how the carbon supply for calcification is affected by carbonate chemistry. We acclimated E. huxleyi to present-day (ambient [CO2], [ inline image], and pH) and OA conditions (high [CO2], ambient [ inline image], low pH). To differentiate between the CO2 and pH/H+ effects, we also acclimated cells to carbonation (high [CO2] and [ inline image], ambient pH) and acidification (ambient [CO2], low [ inline image], and pH). Under these conditions, growth, production of particulate inorganic and organic carbon, as well as carbon and oxygen fluxes were measured. Under carbonation, photosynthesis and calcification were stimulated due to additional inline image uptake, whereas growth was unaffected. Such stimulatory effects are not apparent after short-term carbonation, indicating that cells adjusted their carbon acquisition during acclimation. Being driven by [ inline image], these regulations can, however, not explain typical OA effects. Under acidification and OA, photosynthesis stayed constant, whereas calcification and growth decreased. Similar to the short-term responses toward high [H+], CO2 uptake significantly increased, but inline image uptake decreased. This antagonistic regulation in CO2 and inline image uptake can explain why photosynthesis, being able to use CO2 and inline image, often benefits from OA, whereas calcification, being mostly dependent on inline image, often decreases. We identified H+ as prime driver of coccolithophores’ acclimation responses toward OA. Acidified conditions seem to put metabolic burdens on the cells that result in decreased growth.

Continue reading ‘H+-driven increase in CO2 uptake and decrease in inline image uptake explain coccolithophores’ acclimation responses to ocean acidification’

“From the U.S. West Coast to the Ivory Coast: Building Scientific and Political Capacity to Respond to Ocean Acidification” – U.S. Center side event at the UNFCCC COP22, 9 November 2016, Marrakech

Published 9 November 2016 Events Closed

Time: 4:00 – 5:00 GMT

Primary Sponsor: National Oceanic and Atmospheric Administration (NOAA)

Available in live streaming.

Event Summary: The United States is leading efforts around the world to expand capacity for scientists in developing countries to measure ocean acidification (caused by rising CO2 in the atmosphere) and track its impacts such as erosion of coral reefs or loss of bivalve fisheries. The effect of high CO2 on the oceans is a major reason why the UNFCCC is focusing on figuring out how to reduce temperature increases from 2° to 1.5° C. Several workshops have been held in the past year under auspices of the Global Ocean Acidification (OA) Observing Network to expand participation from African countries. This event will showcase those activities with testimonials from African scientists from Egypt, Namibia and South Africa about the importance of this work for building resilience to ocean acidification in the developing world. The event will end with a call to support an international political alliance focused on OA resilience issued by the U.S. Pacific Coast Collaborative. The international political alliance is teaming with the Global OA Observing Network to leverage political influence to expand resources for this important effort.

Nore information on the U.S. Center side events at the COP22 can be found here.

 

 

Ocean acidification-relevant side events at the UNFCCC COP22, November 2016, Marrakech, Morocco

Published 8 November 2016 Events Closed

“Changing oceans and seas around the world: implications for mitigation and adaptation”

Wednesday, 9 November 2016, 10:30-12:00, EU Pavilion – Room Brussels, Area D, Blue zone

Recent assessments of ocean warming, acidification, deoxygenation and sea-level rise identified serious risks to marine ecosystems, fisheries, and coastal livelihoods and infrastructure. The Paris Agreement recognised the ocean and its ecosystems and the need to ensure their integrity and protect their biodiversity. A panel of international experts (involved in UN assessment reports, and national, EU, international and intergovernmental programmes) will provide an integrated and updated perspective on the climate related changes, risks and projections for both natural and human ocean systems and make mitigation and adaptation recommendations for future UNFCCC processes.

Organised by Plymouth Marine Laboratory; contact – Thecla Keizer, tke(at)pml.ac.uk.

Side event flyer.

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Continue reading ‘Ocean acidification-relevant side events at the UNFCCC COP22, November 2016, Marrakech, Morocco’

Sea snails on acid

Published 8 November 2016 Media coverage Closed
Photo credit: Gabriel Ng

Photo credit: Gabriel Ng

Twice a day the rocky Pacific coast traps seawater in pools as the tide rolls in and out. Compared to the ocean, the puddles are so small and innocuous that it seems nothing momentous could possibly be happening there, but there is. It turns out tiny black turban snails may be getting a buzz from the changing levels of acidity caused by ocean acidification. The scientists at Bodega Marine Lab looked closely at sea stars and snails to find out.

The underside of the purple sea star is covered in tiny delicate suction cups that make one wonder how it moves fast enough to be a voracious hunter, but it is. It’s the bully on the playground, a merciless predator. It can pry open mussel shells, turn its stomach inside out and wrap it around large prey, and digest its meal before even swallowing. It’s no wonder that when black turban snails sense the purple star’s arrival, they all flee to safety, crawling quickly up the side of a tide pool until the enemy leaves the water. Quickly for snails, that is.

Snails have always been good at running away from their primary predator – the purple sea star – until now. Brittany Jellison, a graduate student at University of California Davis, has found in a recent study that the snail’s dramatic response might be slowing down because of ocean acidification. Jellison modified tide pools to mimic ocean acidification conditions. Then she observed the snail’s response by measuring the path they took to safety. What she found when watching the snail was a trippy set of behaviors.

Continue reading ‘Sea snails on acid’

Potential for cumulative effects of human stressors on fish, sea birds and marine mammals in Arctic waters

Published 8 November 2016 Science Closed
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We estimate the potential for cumulative impacts from multiple anthropogenic stressors on fish, sea birds, and marine mammals in the western, southern and south-eastern parts of marine waters around Greenland. The analysis is based on a comprehensive data set representing five human activities including two proxies for climate change, as well as 25 key animal species including commercially important fish and top predators such as sea birds and marine mammals. Anthropogenic stressors are concentrated in two areas: the offshore waters south of Greenland, and especially the western coast from the Qeqertarsuaq (Disko Island) area to the southern tip of Greenland. The latter is also an area of high importance for many key species, thus the potential for cumulative impacts is high along Greenland’s west coast. We conclude that this area should be under high scientific scrutiny and conservation attention. Our study is a first attempt and a stepping-stone towards more detailed and accurate estimates of the effects of multiple human stressors on Arctic marine ecosystems.

Continue reading ‘Potential for cumulative effects of human stressors on fish, sea birds and marine mammals in Arctic waters’

European sea bass show behavioural resilience to near-future ocean acidification

Published 7 November 2016 Science Closed
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Ocean acidification (OA)—caused by rising concentrations of carbon dioxide (CO2)—is thought to be a major threat to marine ecosystems and has been shown to induce behavioural alterations in fish. Here we show behavioural resilience to near-future OA in a commercially important and migratory marine finfish, the Sea bass (Dicentrarchus labrax). Sea bass were raised from eggs at 19°C in ambient or near-future OA (1000 µatm pCO2) conditions and n = 270 fish were observed 59–68 days post-hatch using automated tracking from video. Fish reared under ambient conditions, OA conditions, and fish reared in ambient conditions but tested in OA water showed statistically similar movement patterns, and reacted to their environment and interacted with each other in comparable ways. Thus our findings indicate behavioural resilience to near-future OA in juvenile sea bass. Moreover, simulated agent-based models indicate that our analysis methods are sensitive to subtle changes in fish behaviour. It is now important to determine whether the absences of any differences persist under more ecologically relevant circumstances and in contexts which have a more direct bearing on individual fitness.

Continue reading ‘European sea bass show behavioural resilience to near-future ocean acidification’

Behavioural lateralization and shoaling cohesion of fish larvae altered under ocean acidification

Published 7 November 2016 Science Closed
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Recent studies have shown that the behaviour and development of coral reef fish larvae is hampered by projected future CO2 levels. However, it is uncertain to what extent this effect also occurs in temperate species. The effects that elevated pCO2 (~2000 µatm) levels, which are expected to occur in coastal upwelling regions in the future, have on shoaling behaviour and lateralization (turning preference) of fish, were tested in temperate sand smelt Atherina presbyter larvae. The hypothesis that behavioural changes are caused by interference of high CO2 with GABA-A receptor function was tested by treating larvae with a receptor antagonist (gabazine). Routine swimming speed did not differ between control and high pCO2, but exposure to high pCO2 for 7 days affected group cohesion, which presented a more random distribution when compared to control fish. However, this random distribution was reversed after 21 days of exposure to high CO2 conditions. Lateralization at the individual level decreased in fish exposed to high pCO2 for 7 and 21 days, but gabazine reversed this decline. This adds to the growing body of evidence that the effects of a more acidified environment on fish larvae behaviour are likely due to altered function of GABA-A receptors. Overall, our results suggest that future pCO2 levels likely to occur in temperate coastal ecosystems could have an adverse effect on temperate larval fish behaviour.

Continue reading ‘Behavioural lateralization and shoaling cohesion of fish larvae altered under ocean acidification’

No effect of high pCO2 on juvenile blue crab, Callinectes sapidus, growth and consumption despite positive responses to concurrent warming

Published 7 November 2016 Science Closed
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Future climate scenarios predict increases in both ocean temperature and dissolved carbon dioxide (pCO2) over the next century. Calcifying invertebrates, which depend on specific conditions of temperature and carbonate chemistry for many processes, may be especially affected by these changes. In our study, juvenile blue crab, Callinectes sapidus, were exposed to one of four temperature/pCO2 treatments (ambient/low, ambient/high, high/low, and high/high) for two complete molts. Our study is the first to examine the effect of multiple climate stressors on blue crab and therefore basic responses, including the growth per molt (GPM), inter-molt period (IMP), and food consumption, were quantified. GPM was not affected by either increased temperature or pCO2. Although increased pCO2 did not significantly influence the duration of crab IMP, crabs in warm water had significantly shorter IMP (10.6 ± 3.1 days (± SD)) than crabs in ambient water (12.5 ± 2.8 days). Increased pCO2 did not significantly affect the amount of food crabs consumed, but crabs in warm water ate significantly more food than those in ambient water. These data suggest that the impact of warming outweighs the impact of acidification in juvenile blue crab. The effects of these changes on more complex physiological parameters such as metabolism and carapace chemistry remain to be examined. Additionally, quantifying the changes to the Chesapeake Bay food web that may occur due to the observed increase in crab growth and consumption is important to ensure sustainability of this resource in the face of future climatic changes.

Continue reading ‘No effect of high pCO2 on juvenile blue crab, Callinectes sapidus, growth and consumption despite positive responses to concurrent warming’

Mineralogical response of the Mediterranean crustose coralline alga Lithophyllum cabiochae to near-future ocean acidification and warming (update)

Published 7 November 2016 Science Closed
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Red calcareous coralline algae are thought to be among the organisms most vulnerable to ocean acidification due to the high solubility of their magnesium calcite skeleton. Although skeletal mineralogy is proposed to change as CO2 and temperature continue to rise, there is currently very little information available on the response of coralline algal carbonate mineralogy to near-future changes in pCO2 and temperature. Here we present results from a 1-year controlled laboratory experiment to test mineralogical responses to pCO2 and temperature in the Mediterranean crustose coralline alga (CCA) Lithophyllum cabiochae. Our results show that Mg incorporation is mainly constrained by temperature (+1 mol % MgCO3 for an increase of 3 °C), and there was no response to pCO2. This suggests that L. cabiochae thalli have the ability to buffer their calcifying medium against ocean acidification, thereby enabling them to continue to deposit magnesium calcite with a significant mol % MgCO3 under elevated pCO2. Analyses of CCA dissolution chips showed a decrease in Mg content after 1 year for all treatments, but this was affected neither by pCO2 nor by temperature. Our findings suggest that biological processes exert a strong control on calcification on magnesium calcite and that CCA may be more resilient under rising CO2 than previously thought. However, previously demonstrated increased skeletal dissolution with ocean acidification will still have major consequences for the stability and maintenance of Mediterranean coralligenous habitats.

Continue reading ‘Mineralogical response of the Mediterranean crustose coralline alga Lithophyllum cabiochae to near-future ocean acidification and warming (update)’

Acidification workshop lined up for December

Published 7 November 2016 Media coverage Closed

The Workshop on Understanding the Impacts and Consequences of Ocean Acidification for Commercial Species and End-users (WKACIDUSE) will convene 5-9 December at ICES Secretariat in Copenhagen, leading the organization into areas related to the understanding of acidification and its consequences for marine organisms, ecosystems, and those who use and interact with the ocean. One key outcome of its remit will be collecting the available state of the art science to support the advisory process, acting on a need to translate existing information for decision-making in the long term.

With levels of carbon dioxide being released into Earth’s atmosphere on the rise and now approaching 400 parts per million, the ocean, which absorbs a quarter of the gas, is increasingly bearing the load. The resulting change in seawater chemistry has become one of the most studied marine-related topics in the last decade, and most research suggests the effects vary between groups of organisms, with potentially dramatic consequences for some ecosystems.

Continue reading ‘Acidification workshop lined up for December’

A rippling effect: ocean acidification & food webs

Published 7 November 2016 Science Closed

From people to killer whales, to salmon, to zooplankton, the impacts from ocean acidification can affect a wide variety of organisms. As our oceans become more acidic, shelled organisms like oysters, zooplankton and pteropods have difficulty forming their hard exterior shell, which can lead to a decrease in their population. When populations of shelled organisms begin to decline, food for dependent species also begin to decline. Here off the shores of Washington, the Southern Resident killer whale mainly feeds on chinook salmon, eating around 385 lbs of fish a day! Where chinook salmon feed on small sea snails known as pteropods. As pteropods have already begun to feel the affects from ocean acidification, how will dependent species like chinook salmon and killer whales respond?

Explore the infographic  below to see how ocean acidification affects other marine species throughout the food web.

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The Nature Conservancy, 3 November 2016. Infographic.

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