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Ocean Acidification (ocean + acidification)
Selected AbstractsDie Herausforderung globaler KlimawandelPERSPEKTIVEN DER WIRTSCHAFTSPOLITIK, Issue 2010Mojib Latif The climate problem is therefore closely linked to the way we produce energy. Climate models predict a massive warming by the end of the century should global greenhouse gas emissions not be strongly reduced. The Intergovernmental Panel on Climate Change (IPCC) reports that the warming can amount to up to 4°C in a worst case scenario, which would be unprecedented in speed and extent in man's history. This can lead to an increase of extreme weather events and a rise of global sea level by up to 1m. A less known impact of increasing atmospheric carbon dioxide is ocean acidification, as the oceans take up large amounts of carbon dioxide. Ocean acidification potentially threatens marine life and global food production. [source] The effect of ocean acidification and temperature on the fertilization and embryonic development of the Sydney rock oyster Saccostrea glomerata (Gould 1850)GLOBAL CHANGE BIOLOGY, Issue 9 2009LAURA M. PARKER Abstract This study investigated the synergistic effects of ocean acidification (caused by elevations in the partial pressure of carbon dioxide pCO2) and temperature on the fertilization and embryonic development of the economically and ecologically important Sydney rock oyster, Saccostrea glomerata (Gould 1850). As pCO2 increased, fertilization significantly decreased. The temperature of 26 °C was the optimum temperature for fertilization, as temperature increased and decreased from this optimum, fertilization decreased. There was also an effect of pCO2 and temperature on embryonic development. Generally as pCO2 increased, the percentage and size of D-veligers decreased and the percentage of D-veligers that were abnormal increased. The optimum temperature was 26 °C and embryonic development decreased at temperatures that were above and below this temperature. Abnormality of D-veligers was greatest at 1000 ppm and 18 and 30 °C (,90%) and least at 375 ppm and 26 °C (,4%). Finally prolonged exposure of elevated pCO2 and temperature across early developmental stages led to fewer D-veligers, more abnormality and smaller sizes in elevated CO2 environments and may lead to lethal effects at suboptimal temperatures. Embryos that were exposed to the pCO2 and temperature treatments for fertilization and embryonic development had fewer D-veligers, greater percentage of abnormality and reduced size than embryos that were exposed to the treatments for embryonic development only. Further at the elevated temperature of 30 °C and 750,1000 ppm, there was no embryonic development. The results of this study suggest that predicted changes in ocean acidification and temperature over the next century may have severe implications for the distribution and abundance of S. glomerata as well as possible implications for the reproduction and development of other marine invertebrates. [source] Ecology, politics and policyJOURNAL OF APPLIED ECOLOGY, Issue 3 2007JOHN H. LAWTON Summary 1,The British Ecological Society aims to promote the science of ecology through research and to use the findings of such research to educate the public and influence policy decisions which involve ecological matters.' Yet, how successful have we been in influencing UK and EU environmental policy? 2Many scientists hold to the ,deficit model' of turning science into policy, the view that if only politicians are told what the science reveals, ,correct' policies will automatically follow. Nothing could be further from the truth. Politicians have all kinds of reasons, some valid, some less valid, not to adopt what often seem to us to be common sense policies to protect the environment. 3Here, I explore some of the successes and failures of ecologists to influence UK and European environmental policy, using acid deposition, the collapse of global marine fisheries, GM crops and climate change, carbon dioxide and ocean acidification as examples. I briefly review the extensive literature (largely ignored by natural scientists) on what social scientists have to say about evidence-based policy-making (or the lack of it) and why it often appears to be so difficult to persuade politicians to adopt sound environmental policies. 4Synthesis and applications. Ecologists can, and do, influence government policy on the environment, but often via complex and iterative interactions that can be painfully slow, and may require fundamental changes in politicians' belief systems, values and norms. [source] Seamount science scales undersea mountains: new research and outlookMARINE ECOLOGY, Issue 2010Thomas A. Schlacher Abstract Conventional wisdom suggests that seamounts harbour high levels of biodiversity and endemism, play important roles in marine biogeography, are hotspots of biological carbon processing, and support substantial fisheries. However, since fewer than 300 seamounts have been thoroughly sampled, these generalizations remain largely untested. This has provided the motivation for a number of seamount-focused research projects in recent years, including CenSeam, a field project within the Census of Marine Life. This issue presents some of the research output facilitated by CenSeam. Here we summarize the main findings and provide a précis of future research directions highlighted by contributors to the issue. Recent studies show that seamounts can have comparable levels of benthic diversity and endemism to continental margins, but their communities also include a distinct composition of species that can attain higher biomass. Reported geographic differentiation among seamount communities suggests limited larval dispersal, local speciation, geographic isolation, or a combination of these processes. Genetic studies contained in the issue address these themes explicitly, documenting complex patterns of connectivity that depend on spatial scale and life history characteristics. Globally, seamount ecosystems are also under pressure from bottom-contact fishing and ocean acidification. Contributions detailing the footprint of trawling and a risk assessment confirm what has long been suspected: seamount ecosystems are highly vulnerable to disturbance by bottom trawling and recovery from fishing impacts is a lengthy process, likely requiring decades at a minimum. A predicted shallowing of the aragonite saturation horizon caused by ocean acidification is predicted to place deep-water corals at risk, but seamounts may yet provide a spatial/chemical refuge from these impacts. The issue concludes with a ,myth-buster' synthesis that updates the status of the various seamount ecological paradigms. [source] Die Herausforderung globaler KlimawandelPERSPEKTIVEN DER WIRTSCHAFTSPOLITIK, Issue 2010Mojib Latif The climate problem is therefore closely linked to the way we produce energy. Climate models predict a massive warming by the end of the century should global greenhouse gas emissions not be strongly reduced. The Intergovernmental Panel on Climate Change (IPCC) reports that the warming can amount to up to 4°C in a worst case scenario, which would be unprecedented in speed and extent in man's history. This can lead to an increase of extreme weather events and a rise of global sea level by up to 1m. A less known impact of increasing atmospheric carbon dioxide is ocean acidification, as the oceans take up large amounts of carbon dioxide. Ocean acidification potentially threatens marine life and global food production. [source] Biogeographical and ecological context for managing threats to coral and rocky reef communities in the Lord Howe Island Marine Park, south-western PacificAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 4 2010Graham J. Edgar Abstract 1.Quantitative subtidal surveys of fishes, macro-invertebrates and sessile organisms at 33 sites within the Lord Howe Island Marine Park revealed a rich fauna and flora, including 164 fishes, 40 mobile invertebrate taxa, 53 coral and other sessile invertebrate taxa, 32 algal taxa, and two seagrasses. The biota in this newly-zoned marine park was overwhelmingly tropical when species lists were tabulated; however, species with distributions centred on temperate coasts of eastern Australia and New Zealand occurred in disproportionately high densities compared with the tropical species. 2.Lord Howe Island reefs were generally in good condition. Virtually no bleached coral was observed (0.2% of the reef surface; 0.8% of total hard coral cover). Living scleractinian coral comprised the predominant group of organisms growing on reef surfaces, with 25.5% cover overall. Other major taxa observed were brown algae (18.8% cover) and red algae (16.9% cover). 3.Three distinctive community types were identified within the marine park,coral reefs, macroalgal beds and an offshore/open coast community. The distribution of these community types was strongly related to wave exposure, as indicated by an extremely high correlation with the first principal coordinates axis for biotic data (R2=0.80). 4.The close (<3,km) proximity of tropical coral and temperate macroalgal community types off Lord Howe Island is highly unusual, with localized patterns of nutrient enrichment suggested as the primary cause. The macroalgal community type is only known from a small area off the south-western coast that is not protected from fishing. This community is considered highly susceptible to threats because of potential impacts of global warming and the possibility of expansion of sea urchin barrens. Coral bleaching and ocean acidification associated with global climate change also threaten the coral reef community, which includes relatively high numbers of endemic and near endemic fish species. Copyright © 2009 John Wiley & Sons, Ltd. [source] Der globale Kohlenstoffkreislauf im Anthropozän.CHEMIE IN UNSERER ZEIT (CHIUZ), Issue 2 2010Betrachtung aus meereschemischer Perspektive Abstract Durch die Verbrennung fossiler Brennstoffe werden durch die Menschheit jährlich über 8 Milliarden Tonnen Kohlenstoff (Gt C) in Form von CO2 in die Atmosphäre emittiert. Die kumulativen Emissionen seit Beginn der industriellen Revolution haben zu einem Anstieg der atmosphärischen CO2 -Konzentration geführt, die einen zusätzlichen anthropogenen Treibhauseffekt zur Folge hat. Von den drei auf der Zeitskala von Jahrhunderten austauschenden Kohlenstoffreservoiren Atmosphäre, terrestrische Biosphäre und Ozean ist der Ozean bei weitem das größte. Das CO2 -System des Meerwassers umfasst die chemischen Spezies HCO3,, CO32, und CO2(aq). Daraus resultiert die pH-puffernde Eigenschaft des Meerwassers sowie seine hohe Aufnahmekapazität für anthropogenes CO2. Mit Hilfe von vier chemischen Messgrößen kann das marine CO2 -System analytisch sehr präzise beschrieben werden. Diese Messgrößen dienen als sensitive "Sensoren" für physikalische, chemische und biologische Vorgänge im Meer. Im marinen Kohlenstoffkreislauf sind größere natürliche Prozesse aktiv, die Kohlenstoff mit der Atmosphäre austauschen und im Innern der Ozeans umverteilen. Diese Prozesse werden auch als "Pumpen" bezeichnet und sowohl durch physikalische als auch biologische Faktoren angetrieben. Während die "physikalische Pumpe" unmittelbar durch die Aufnahme von anthropogenem CO2 aus der Atmosphäre verstärkt wird, ist dieses für die beiden "biologischen Pumpen" bisher ungeklärt. Eine Vielzahl von potenziellen Konsequenzen des globalen Wandels (Temperaturanstieg, marine CO2 -Aufnahme, Ozeanversauerung) auf marine Ökosysteme sind identifiziert worden. Diese werden gegenwärtig intensiv hinsichtlich ihrer Klimasensitivität sowie ihres Rückkopplungspotenzials auf das Klima untersucht. Es ist jedoch kaum vorstellbar, dass die "biologischen Pumpen" sich unter dem Einfluss des globalen Wandels nicht verändern werden. By burning of fossil fuels humankind emits more than 8 billion tons of carbon (Gt C) in the form of CO2 to the atmosphere. Since the onset of the industrial revolution the cumulative emissions have led to an increase of the atmospheric CO2 concentration which corresponds to an additional radiative forcing in the atmosphere. Of the three reservoirs which exchange carbon on the time scale of centuries , atmosphere, terrestrial biosphere, and ocean , the ocean is by far the largest. The marine CO2 system comprises the chemical species HCO3,, CO32,, and CO2(aq). This gives rise to the pH-buffering nature of seawater as well as its high uptake capacity for anthropogenic CO2. Four measurement parameters of the marine CO2 system are available for an accurate analytical characterization. These parameters also provide a means of sensing the role of physical, chemical, and biological drivers for the marine carbon cycle. The marine carbon cycle features major natural processes that exchange carbon with the atmosphere and re-distribute it throughout the ocean. These are known as "pumps" and driven by physical and biological factors. While the "physical pump" is inevitably enhanced by the oceanic uptake of anthropogenic CO2, even the sign of the response is currently not clear for the "biological pumps". A host of potential consequences of global change (temperature rise, ocean carbonation, ocean acidification) have been identified. These are currently studied intensively with respect to their climate sensitivity as well as the climate feedback potential. [source] | ||||||||||