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Impacts of ocean acidification on marine shelled molluscs

Published 26 April 2013 Science Closed
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Over the next century, elevated quantities of atmospheric CO2 are expected to penetrate into the oceans, causing a reduction in pH (−0.3/−0.4 pH unit in the surface ocean) and in the concentration of carbonate ions (so-called ocean acidification). Of growing concern are the impacts that this will have on marine and estuarine organisms and ecosystems. Marine shelled molluscs, which colonized a large latitudinal gradient and can be found from intertidal to deep-sea habitats, are economically and ecologically important species providing essential ecosystem services including habitat structure for benthic organisms, water purification and a food source for other organisms. The effects of ocean acidification on the growth and shell production by juvenile and adult shelled molluscs are variable among species and even within the same species, precluding the drawing of a general picture. This is, however, not the case for pteropods, with all species tested so far, being negatively impacted by ocean acidification. The blood of shelled molluscs may exhibit lower pH with consequences for several physiological processes (e.g. respiration, excretion, etc.) and, in some cases, increased mortality in the long term. While fertilization may remain unaffected by elevated pCO2, embryonic and larval development will be highly sensitive with important reductions in size and decreased survival of larvae, increases in the number of abnormal larvae and an increase in the developmental time. There are big gaps in the current understanding of the biological consequences of an acidifying ocean on shelled molluscs. For instance, the natural variability of pH and the interactions of changes in the carbonate chemistry with changes in other environmental stressors such as increased temperature and changing salinity, the effects of species interactions, as well as the capacity of the organisms to acclimate and/or adapt to changing environmental conditions are poorly described.

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Predicting the response of molluscs to the impact of ocean acidification

Published 10 April 2013 Science Closed
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Elevations in atmospheric carbon dioxide (CO2) are anticipated to acidify oceans because of fundamental changes in ocean chemistry created by CO2 absorption from the atmosphere. Over the next century, these elevated concentrations of atmospheric CO2 are expected to result in a reduction of the surface ocean waters from 8.1 to 7.7 units as well as a reduction in carbonate ion (CO32−) concentration. The potential impact that this change in ocean chemistry will have on marine and estuarine organisms and ecosystems is a growing concern for scientists worldwide. While species-specific responses to ocean acidification are widespread across a number of marine taxa, molluscs are one animal phylum with many species which are particularly vulnerable across a number of life-history stages. Molluscs make up the second largest animal phylum on earth with 30,000 species and are a major producer of CaCO3. Molluscs also provide essential ecosystem services including habitat structure and food for benthic organisms (i.e., mussel and oyster beds), purification of water through filtration and are economically valuable. Even sub lethal impacts on molluscs due to climate changed oceans will have serious consequences for global protein sources and marine ecosystems.

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Threats to ultraoligotrophic marine ecosystems

Published 9 April 2013 Science Closed
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Ocean acidification is discussed in Section 3 of this book chapter.

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Temperate reefs in a changing ocean: skeletal carbonate mineralogy of serpulids

Published 3 April 2013 Science Closed
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We present a review of the published data about serpulid skeletal carbonate geochemistry, augmented with new data from the Southern Hemisphere. We know something about skeletal carbonate mineralogy of 15 % of extant species (n = 52); and about half of extant genera (n = 25). Serpulid worm tubes vary in their skeletal mineralogy from entirely aragonitic (about 24 % of species) to entirely high-Mg calcite (40 %) to mixtures of the two. Mg in calcite ranges from 7 to 15 wt% MgCO3, with a mean of 11 wt% MgCO3. Little mineralogical variation within individuals or species can be found in aragonitic specimens, whereas high-Mg calcitic species show somewhat more variability in both calcite and Mg content, and those with mixed mineralogies are highly variable. These three groups correspond broadly with currently accepted clades. Given this strong phylogenetic signal, we analysed the data using phylogenetically independent contrasts, a statistical approach that separates genotypic from phenotypic variability; we found that variations which might be ascribed to environment were generally weak. The mineralogy of serpulid tubes makes them particularly vulnerable to ocean chemistry changes. While some serpulids appear to be able to adjust their tube mineralogy in order to adapt to sea-water chemistry, overall strength and elasticity may be sacrificed when they do. The biodiverse reef habitat provided by serpulids in some temperate regions may be the only complex solid habitat available, and loss or compromise of these temperate reefs will most likely have deleterious flow-on effects on temperate benthic communities.

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Addressing ocean acidification as part of sustainable ocean development

Published 3 April 2013 Science Closed
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Many of the declarations and outcome documents from prior United Nations international meetings address ocean issues such as fishing, pollution, and climate change, but they do not address ocean acidification. This progressive alteration of seawater chemistry caused by uptake of atmospheric carbon dioxide (CO2) is an emerging issue of concern that has potential consequences for marine ecosystems and the humans that depend on them. Addressing ocean acidification will require mitigation of global CO2 emissions at the international level accompanied by regional marine resource use adaptations that reduce the integrated pressure on marine ecosystems while the global community works towards implementing permanent CO2 emissions reductions. Addressing ocean acidification head-on is necessary because it poses a direct challenge to sustainable development targets such as the Millennium Development Goals, and it cannot be addressed adequately with accords or geoengineering plans that do not specifically decrease atmospheric carbon dioxide levels. Here, we will briefly review the current state of ocean acidification knowledge and identify several mitigation and adaptation strategies that should be considered along with reductions in CO2 emissions to reduce the near-term impacts of ocean acidification. Our goal is to present potential options while identifying some of their inherent weaknesses to inform decisionmaking discussions, rather than to recommend adoption of specific policies. While the reduction of CO2 emissions should be the number one goal of the international community, it is unlikely that the widespread changes and infrastructure redevelopment necessary to accomplish this will be achieved soon, before ocean acidification’s short-term impacts become significant. Therefore, a multi-faceted approach must be employed to address this growing problem.

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Climate change and intertidal wetlands

Published 27 March 2013 Science Closed
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Intertidal wetlands are recognised for the provision of a range of valued ecosystem services. The two major categories of intertidal wetlands discussed in this contribution are saltmarshes and mangrove forests. Intertidal wetlands are under threat from a range of anthropogenic causes, some site-specific, others acting globally. Globally acting factors include climate change and its driving cause—the increasing atmospheric concentrations of greenhouse gases. One direct consequence of climate change will be global sea level rise due to thermal expansion of the oceans, and, in the longer term, the melting of ice caps and glaciers. The relative sea level rise experienced at any one locality will be affected by a range of factors, as will the response of intertidal wetlands to the change in sea level. If relative sea level is rising and sedimentation within intertidal wetlands does not keep pace, then there will be loss of intertidal wetlands from the seaward edge, with survival of the ecosystems only possible if they can retreat inland. When retreat is not possible, the wetland area will decline in response to the “squeeze” experienced. Any changes to intertidal wetland vegetation, as a consequence of climate change, will have flow on effects to biota, while changes to biota will affect intertidal vegetation. Wetland biota may respond to climate change by shifting in distribution and abundance landward, evolving or becoming extinct. In addition, impacts from ocean acidification and warming are predicted to affect the fertilisation, larval development, growth and survival of intertidal wetland biota including macroinvertebrates, such as molluscs and crabs, and vertebrates such as fish and potentially birds. The capacity of organisms to move and adapt will depend on their life history characteristics, phenotypic plasticity, genetic variability, inheritability of adaptive characteristics, and the predicted rates of environmental change.

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Ocean acidification

Published 25 March 2013 Science Closed
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Ocean acidification is the multidecadal decrease in ocean pH and change in seawater inorganic carbon chemistry caused primarily by uptake of anthropogenic carbon dioxide (CO2) from the atmosphere. Global surface ocean mean pH has decreased from 8.2 to 8.1 over the past two centuries; the current pH decrease is about 10-100 times faster than past trends observed in the recent geological record. As CO2 dissolves into the ocean, it decreases pH as well as carbonate ion concentrations (CO32–). Carbonate ions are required for the hard calcium carbonate (CaCO3) shells and skeletons that many marine organisms create. Many organisms decrease their rate of CaCO3 production in response to ocean acidification. Other biological responses to ocean acidification include changes in photosynthesis and respiration, alterations in behavior, and shifts in intracellular chemistry. Ocean acidification may also alter the biogeochemical cycling of nitrogen, carbon, and micronutrients. Direct impacts on individual organisms could then indirectly affect local ecosystems via altered predator-prey relationships, competition, and habitat availability. Ecosystems that will most likely be affected include coral reefs, open ocean environments, high-latitude oceans, and deep-sea regions. Susceptible species provide human communities with many goods and services, so human communities may feel the effects of ocean acidification in several ways.

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Mixed responses of tropical Pacific fisheries and aquaculture to climate change

Published 19 March 2013 Science Closed
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Pacific Island countries have an extraordinary dependence on fisheries and aquaculture. Maintaining the benefits from the sector is a difficult task, now made more complex by climate change. Here we report how changes to the atmosphere–ocean are likely to affect the food webs, habitats and stocks underpinning fisheries and aquaculture across the region. We found winners and losers—tuna are expected to be more abundant in the east and freshwater aquaculture and fisheries are likely to be more productive. Conversely, coral reef fisheries could decrease by 20% by 2050 and coastal aquaculture may be less efficient. We demonstrate how the economic and social implications can be addressed within the sector—tuna and freshwater aquaculture can help support growing populations as coral reefs, coastal fisheries and mariculture decline.

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Is ocean acidification an open-ocean syndrome? Understanding anthropogenic impacts on seawater pH

Published 5 March 2013 Science Closed
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Ocean acidification due to anthropogenic CO2 emissions is a dominant driver of long-term changes in pH in the open ocean, raising concern for the future of calcifying organisms, many of which are present in coastal habitats. However, changes in pH in coastal ecosystems result from a multitude of drivers, including impacts from watershed processes, nutrient inputs, and changes in ecosystem structure and metabolism. Interaction between ocean acidification due to anthropogenic CO2 emissions and the dynamic regional to local drivers of coastal ecosystems have resulted in complex regulation of pH in coastal waters. Changes in the watershed can, for example, lead to changes in alkalinity and CO2 fluxes that, together with metabolic processes and oceanic dynamics, yield high-magnitude decadal changes of up to 0.5 units in coastal pH. Metabolism results in strong diel to seasonal fluctuations in pH, with characteristic ranges of 0.3 pH units, with metabolically intense habitats exceeding this range on a daily basis. The intense variability and multiple, complex controls on pH implies that the concept of ocean acidification due to anthropogenic CO2 emissions cannot be transposed to coastal ecosystems directly. Furthermore, in coastal ecosystems, the detection of trends towards acidification is not trivial and the attribution of these changes to anthropogenic CO2 emissions is even more problematic. Coastal ecosystems may show acidification or basification, depending on the balance between the invasion of coastal waters by anthropogenic CO2, watershed export of alkalinity, organic matter and CO2, and changes in the balance between primary production, respiration and calcification rates in response to changes in nutrient inputs and losses of ecosystem components. Hence, we contend that ocean acidification from anthropogenic CO2 is largely an open-ocean syndrome and that a concept of anthropogenic impacts on marine pH, which is applicable across the entire ocean, from coastal to open-ocean environments, provides a superior framework to consider the multiple components of the anthropogenic perturbation of marine pH trajectories. The concept of anthropogenic impacts on seawater pH acknowledges that a regional focus is necessary to predict future trajectories in the pH of coastal waters and points at opportunities to manage these trajectories locally to conserve coastal organisms vulnerable to ocean acidification.

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Ocean acidification

Published 27 February 2013 Science Closed
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The oceans play a central role in the maintenance of life on Earth. Oceans provide extensive ecosystems for marine animals and plants covering two-thirds of the Earth’s surface, are essential sources of food, economic activity, and biodiversity, and are central to the global biogeochemical cycles. The oceans are the largest reservoir of carbon in the Planet, and absorb approximately one-third of the carbon emissions that are released to the Earth’s atmosphere as a result of human activities. Since the beginning of industrialization, humans have been responsible for the increase in one greenhouse gas, carbon dioxide (CO2), from approximately 280 parts per million (ppm) at the end of the nineteenth century to the current levels of 390ppm. As well as affecting the surface ocean pH, and the organisms living at the ocean surface, these increases in CO2 are causing global mean surface temperatures to rise.

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Enhanced chemical weathering as a geoengineering strategy to reduce atmospheric carbon dioxide, a nutrient source and to mitigate ocean acidification

Published 20 February 2013 Science Closed
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[1] Chemical weathering is an integral part of both the rock and carbon cycles and is being affected by changes in land use, particularly as a result of agricultural practices such as tilling, mineral fertilization, or liming to adjust soil pH. These human activities have already altered the chemical terrestrial cycles and land-ocean flux of major elements, although the extent remains difficult to quantify. When deployed on a grand scale, Enhanced Weathering (a form of mineral fertilization), the application of finely ground minerals over the land surface, could be used to remove CO2 from the atmosphere. The release of cations during the dissolution of such silicate minerals would convert dissolved CO2 to bicarbonate, increasing the alkalinity and pH of natural waters. Some products of mineral dissolution would precipitate in soils or taken up by ecosystems, but a significant portion would be transported to the coastal zone and the open ocean, where the increase in alkalinity would partially counteract “ocean acidification” associated with the current marked increase in atmospheric CO2. Other elements released during this mineral dissolution, like Si, P or K, could stimulate biological productivity, further helping to remove CO2 from the atmosphere. On land, the terrestrial carbon-pool would likely increase in response to Enhanced Weathering in areas where ecosystem growth rates are currently limited by one of the nutrients that would be released during mineral dissolution.In the ocean, the biological carbon pumps (which export organic matter and CaCO3 to the deep ocean) may be altered by the resulting influx of nutrients and alkalinity to the ocean.

[2] This review merges current interdisciplinary knowledge about Enhanced Weathering, the processes involved, and the applicability as well as some of the consequences and risks of applying the method.

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Advances in studies of ocean acidification

Published 19 February 2013 Science Closed
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During the past 200 years, approximately one-half of the carbon dioxide from human activities is being taken up by the oceans. The uptake of carbon dioxide has led to a reduction of the pH value of surface seawater of 0.1 units, equivalent to a 30% increase in the concentration of hydrogen ions. If global emission of carbon dioxide from human activities continues to rise at the current rates, the average pH value of the oceans could fall by 0.5 units by the year 2100. This was equivalent to a three fold increase in the concentration of hydrogen ions. Global ocean acidification has become one of the most threatening disasters to the ocean ecosystem and has been attached great importance by the countries adjacent to oceans and the related international organizations in the world. In this paper the current situation and development of ocean acidification and the impacts of ocean acidification are described. It also summarizes the latest research achievements of ocean acidification and the ocean acidification studies in such countries as US, Europe, Japan, Australia, the Republic of Korea, and China, etc.

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Effect of ocean acidification on the benthic foraminifera Ammonia sp. is caused by a decrease in carbonate ion concentration

Published 25 January 2013 Science Closed
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About 30% of the anthropogenically released CO2 is taken up by the oceans, which causes surface ocean pH to decrease and is commonly referred to as Ocean Acidification (OA). Foraminifera are one of the most abundant groups of marine calcifiers, estimated to precipitate ca. 50% of biogenic calcium carbonate in the open oceans. We have compiled the state of the art of OA effects on foraminifera, because the majority of OA research on this group was published within the last 3 yr. Disparate responses of this important group of marine calcifiers to OA were reported, highlighting the importance of a process based understanding of OA effects on foraminifera. The benthic foraminifer Ammonia sp. was cultured using two carbonate chemistry manipulation approaches: While pH and carbonate ions where varied in one, pH was kept constant in the other while carbonate ion concentration varied. This allows the identification of teh parameter of the parameter of the carbonate system causing observed effects. This parameter identification is the first step towards a process based understanding. We argue that [CO32−] is the parameter affecting foraminiferal size normalized weights (SNW) and growth rates and based on the presented data we can confirm the strong potential of foraminiferal SNW as a [CO32−] proxy.

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Effects of climate change on global seaweed communities

Published 21 January 2013 Science Closed
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Seaweeds are ecologically important primary producers, competitors, and ecosystem engineers that play a central role in coastal habitats ranging from kelp forests to coral reefs. Although seaweeds are known to be vulnerable to physical and chemical changes in the marine environment, the impacts of ongoing and future anthropogenic climate change in seaweed-dominated ecosystems remain poorly understood. In this review, we describe the ways in which changes in the environment directly affect seaweeds in terms of their physiology, growth, reproduction, and survival. We consider the extent to which seaweed species may be able to respond to these changes via adaptation or migration. We also examine the extensive reshuffling of communities that is occurring as the ecological balance between competing species changes, and as top-down control by herbivores becomes stronger or weaker. Finally, we delve into some of the ecosystem-level responses to these changes, including changes in primary productivity, diversity, and resilience. Although there are several key areas in which ecological insight is lacking, we suggest that reasonable climate-related hypotheses can be developed and tested based on current information. By strategically prioritizing research in the areas of complex environmental variation, multiple stressor effects, evolutionary adaptation, and population, community, and ecosystem-level responses, we can rapidly build upon our current understanding of seaweed biology and climate change ecology to more effectively conserve and manage coastal ecosystems.

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Experimental evolution meets marine phytoplankton

Published 4 January 2013 Science Closed
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Our perspective highlights potentially important links between disparate fields – biological oceanography, climate change research, and experimental evolutionary biology. We focus on one important functional group – photoautotrophic microbes (phytoplankton) which are responsible for ∼50% of global primary productivity. Global climate change currently results in the simultaneous change of several conditions such as warming, acidification and nutrient supply. It thus has the potential to dramatically change phytoplankton physiology, community composition, and may result in adaptive evolution. Although their large population sizes, standing genetic variation and rapid turnover time should promote swift evolutionary change, oceanographers have focussed on describing patterns of present day physiological differentiation rather than measure potential adaptation in evolution experiments, the only direct way to address whether and at which rate phytoplankton species will adapt to environmental change. Important open questions are (i) is adaptation limited by existing genetic variation or fundamental constraints? (ii) will complex ecological settings such as gradual vs. abrupt environmental change influence adaptation processes? (iii) how will increasing environmental variability affect the evolution of phenotypic plasticity patterns? Since marine phytoplankton species display rapid acclimation capacity (phenotypic buffering), a systematic study of reaction norms renders them particularly interesting to the evolutionary biology research community.

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Preparing to manage coral reefs for ocean acidification: lessons from coral bleaching

Published 27 December 2012 Science Closed
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Ocean acidification is a direct consequence of increasing atmospheric carbon dioxide concentrations and is predicted to compromise the structure and function of coral reefs within this century. Research into the effects of ocean acidification on coral reefs has focused primarily on measuring and predicting changes in seawater carbon (C) chemistry and the biological and geochemical responses of reef organisms to such changes. To date, few ocean acidification studies have been designed to address conservation planning and management priorities. Here, we discuss how existing marine protected area design principles developed to address coral bleaching may be modified to address ocean acidification. We also identify five research priorities needed to incorporate ocean acidification into conservation planning and management: (1) establishing an ocean C chemistry baseline, (2) establishing ecological baselines, (3) determining species/habitat/community sensitivity to ocean acidification, (4) projecting changes in seawater carbonate chemistry, and (5) identifying potentially synergistic effects of multiple stressors.

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The effects of changing climate on microzooplankton grazing and community structure: drivers, predictions and knowledge gaps

Published 19 December 2012 Science Closed
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Microzooplankton dominate trophic interactions and biogeochemical processes at the base of pelagic marine food webs and so their responses to a changing ocean environment have potentially large implications for ocean ecosystem functioning. This diverse array of mostly protistan species constitutes an important source of phytoplankton and bacterial mortality, and contributes significantly to the food available to higher trophic levels by packaging minute prey into larger particle sizes that can be consumed by metazooplankton. Microzooplankton are pivotal species in oceanic food webs and nutrient remineralization and so it is essential that we understand the effects that changing climate may have on the biomass, species composition and trophic activities of these assemblages. Yet, our present understanding of this topic is derived from experimental studies of relatively few species subjected to specific environmental variables (e.g. changes in temperature, CO2, pH) in isolated culture. Most experiments and models employed to predict the effects of climate change have focussed on primary productivity and phytoplankton community structure, with less attention paid to microbial heterotrophy. Here we outline some of the major direct and indirect changes in environmental variables that are anticipated to accompany global climate change, and our present state of knowledge regarding their potential impacts on natural microzooplankton assemblages. We highlight a few specific areas for studies to address glaring omissions in our knowledge regarding how global change influences microzooplankton abundances and activities, and hypothesize that their ecological and biogeochemical roles may become even more prominent due to expected future shifts in marine chemistry and climate.

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Integrating climate-related stressor effects on marine organisms: unifying principles linking molecule to ecosystem-level changes

Published 10 December 2012 Science Closed
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Climate change effects on marine ecosystems involve various stressors, predominantly temperature, hypoxia and CO2, all of which may combine with further anthropogenic stressors such as pollutants. All life forms respond to these drivers, following potentially common principles, which are insufficiently understood. Specific understanding may be most advanced in animals where the concept of ‘oxygen and capacity dependent thermal tolerance’ (OCLTT) is an integrator of various effects, linking molecular to ecosystem levels of biological organisation. Recent studies confirm OCLTT involvement in the field, causing changes in species abundance, biogeographical ranges, phenology and species predominance. At the whole-animal level, performance capacity set by aerobic scope and energy budget, building on baseline energy turnover, links fitness (within a thermal window) and functioning at the ecosystem level. In variable environments like the intertidal zone, animals also exploit their capacity for passive tolerance. While presently the temperature signal appears predominant in the field, effects may well involve other stressors, acting synergistically by narrowing the aerobic OCLTT window. Recent findings support the OCLTT concept as a common physiological basis linking apparently disjunct effects of ocean warming, acidification and hypoxia in a so-called climate syndrome. In brief, warming-induced CO2 accumulation in body fluids links to the effects of ocean acidification mediated by the weak acid distribution of CO2. Temperature-induced hypoxemia links to the hypoxia sensitivity of thermal tolerance. Future work will need to develop proxies for the temperature-dependent effects of climate-related stressors and also identify the principles operative in organisms other than animals and their underlying mechanisms. Mechanism-based modelling efforts are then needed to develop reliable organism to ecosystem projections of future change.

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The biological pump in a high CO2 world

Published 10 December 2012 Science Closed
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The vertical separation of organic matter formation from respiration can lead to net carbon sequestration within the ocean’s interior, making the biological pump an important component of the global carbon cycle. Understanding the response of the biological pump to the changing environment is a prerequisite to predicting future atmospheric carbon dioxide concentrations. Will the biological pump weaken or strengthen? Currently the ocean science community is unable to confidently answer this question. Carbon flux at approximately 1000 m depth, the sequestration flux, determines the removal of carbon from the atmosphere on time scales ≥100 yr. The sequestration flux depends upon: (1) input rates of nutrients allochthonous to the ocean, (2) the export flux at the base of the euphotic zone, (3) the deviation of carbon fixation and remineralization from Redfield stoichiometry, and (4) the flux attenuation in the upper 1000 m. The biological response to increasing temperature, ocean stratification, nutrient availability and ocean acidification is frequently taxa- and ecosystem-specific and the results of synergistic effects are challenging to predict. Consequently, the use of global averages and steady state assumptions (e.g. Redfield stoichiometry, mesopelagic nutrient inventory) for predictive models is often insufficient. Our ability to predict sequestration flux additionally suffers from a lack of understanding of mesopelagic food web functioning and flux attenuation. However, regional specific investigations show great promise, suggesting that in the near future predictions of changes to the biological pump will have to be regionally and ecosystem specific, with the ultimate goal of integrating to global scales.

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Global change and the future of harmful algal blooms in the ocean

Published 10 December 2012 Science Closed
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The frequency and intensity of harmful algal blooms (HABs) and phytoplankton community shifts toward toxic species have increased worldwide. Although most research has focused on eutrophication as the cause of this trend, many other global- and regional-scale anthropogenic influences may also play a role. Ocean acidification (high pCO2/low pH), greenhouse warming, shifts in nutrient availability, ratios, and speciation, changing exposure to solar irradiance, and altered salinity all have the potential to profoundly affect the growth and toxicity of these phytoplankton. Except for ocean acidification, the effects of these individual factors on harmful algae have been studied extensively. In this review, we summarize our understanding of the influence of each of these single factors on the physiological properties of important marine HAB groups. We then examine the much more limited literature on how rising CO2 together with these other concurrent environmental changes may affect these organisms, including what is possibly the most critical property of many species: toxin production. New work with several diatom and dinoflagellate species suggests that ocean acidification combined with nutrient limitation or temperature changes may dramatically increase the toxicity of some harmful groups. This observation underscores the need for more in-depth consideration of poorly understood interactions between multiple global change variables on HAB physiology and ecology. A key limitation of global change experiments is that they typically span only a few algal generations, making it difficult to predict whether they reflect likely future decadal- or century-scale trends. We conclude by calling for thoughtfully designed experiments and observations that include adequate consideration of complex multivariate interactive effects on the long-term responses of HABs to a rapidly changing future marine environment.

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