Archive for December, 2014

Best wishes for an amazing 2015 from the OA-ICC team!

NY card 2015

OA-ICC December calendar: 30/12 – “Spin the OA story with the Google Earth tour!”

Count down the days until 2015 together with the OA-ICC! Each day of December you will find a short story on the OA-ICC news stream highlighting an ocean acidification project, effort, or resource.
Discover today’s story below: “Spin the OA story with the Google Earth tour!”

Continue reading ‘OA-ICC December calendar: 30/12 – “Spin the OA story with the Google Earth tour!”’

Fabriciidae (Annelida, Sabellida) from a naturally acidified coastal system (Italy) with description of two new species

Polychaete worms are known to thrive in extreme environmental conditions, however little is known about how polychaete species will respond to major climatic stressors, such as ocean acidification. Here, we examined the distribution of Fabriciidae (Annelida, Sabellida) species along a gradient of ocean acidification, caused by carbon dioxide (CO2) vent emissions in a shallow, coastal system off the island of Ischia (Tyrrhenian Sea, Italy). A total of 265 specimens of Fabriciidae, representing six species from five genera, were collected along the gradient. Most of the species were found across the entire CO2 gradient, suggesting polychaetes may have a high tolerance for ocean acidification in the future. Two of the species were new to science, and two of the genera were previously unrecorded in the Mediterranean. A full description of the new species Brifacia aragonensis sp. nov. andParafabricia mazzellae sp. nov. is given, both of which were most abundant in the most acidified areas (pH 6.6–7.2). The geographical distribution and ecology of the new taxa, as well as of the other fabriciid species collected, is discussed. Taxonomic keys to identify the Fabriciidae species currently recorded in the Mediterranean Sea are also provided.

Continue reading ‘Fabriciidae (Annelida, Sabellida) from a naturally acidified coastal system (Italy) with description of two new species’

Rapid response of the active microbial community to CO2 exposure from a controlled sub-seabed CO2 leak in Ardmucknish Bay (Oban, Scotland)

The response of the benthic microbial community to a controlled sub-seabed CO2 leak was assessed using quantitative PCR measurements of benthic bacterial, archaeal and cyanobacteria/chloroplast 16S rRNA genes. Samples were taken from four zones (epicentre; 25 m distant, 75 m distant and 450 m distant) during 6 time points (7 days before CO2 exposure, after 14 and 36 days of CO2 release, and 6, 20 and 90 days after the CO2 release had ended). Changes to the active community of microphytobenthos and bacteria were also assessed before, during and after CO2 release. Increases in the abundance of microbial 16S rRNA were detected after 14 days of CO2 release and at a distance of 25 m from the epicentre. CO2 related changes to the relative abundance of both major and minor bacterial taxa were detected: most notably an increase in the relative abundance of the Planctomycetacia after 14 days of CO2 release. Also evident was a decrease in the abundance of microbial 16S rRNA genes at the leak epicentre during the initial recovery phase: this coincided with the highest measurements of DIC within the sediment, but may be related to the release of potentially toxic metals at this time point.

Continue reading ‘Rapid response of the active microbial community to CO2 exposure from a controlled sub-seabed CO2 leak in Ardmucknish Bay (Oban, Scotland)’

OA-ICC December calendar: 29/12- “Living La Vida LAOCA!”

Count down the days until 2015 together with the OA-ICC! Each day of December you will find a short story on the OA-ICC news stream highlighting an ocean acidification project, effort, or resource.

Discover today’s story below: “Living La Vida LAOCA!”

Continue reading ‘OA-ICC December calendar: 29/12- “Living La Vida LAOCA!”’

New study finds Alaskans familiar with ocean acidification, not aware of risks to fisheries

620300c1768EDNmain10966Port Conclusion from Natalie Monacci 2New research published in Marine Policy from the first Alaska-focused study on public understanding and awareness of ocean acidification risk shows that Alaskans are three times more aware of ocean acidification than Americans in general.  However, Alaskans have difficulty seeing ocean acidification as an immediate risk, and the direct risks to Alaska’s fisheries are still not well understood. The research, “Gauging perceptions of ocean acidification in Alaska,” can be read online.

In Alaska, the impacts of ocean acidification have the potential to be even worse than “other coastal communities because of an accelerated rate of change in ocean chemistry, and statewide reliance on commercial and subsistence fishing. Accurately evaluating ocean acidification risk directly influences the ability to respond to change. The research builds on earlier NOAA-led research showing that communities in southeast and southwest Alaska are more at risk than other areas of the state because of their heavy reliance on fisheries expected to be impacted by ocean acidification.

Continue reading ‘New study finds Alaskans familiar with ocean acidification, not aware of risks to fisheries’

Climate change threat to mussels’ shells

The world’s mussel population could be under threat as climate change causes oceans to become increasingly acidic, scientists have discovered.

In a new paper published today (Wednesday 24 December) in the Royal Society’s journal Interface, researchers from the University of Glasgow describe how mussels’ shells become more brittle when they are formed in more acidic water.

The world’s oceans are becoming increasingly acidic as they absorb some of the atmospheric carbon dioxide which contributes to climate change. The water reacts with the carbon dioxide to form carbonic acid, which is gradually lowering the pH of the oceans. Scientists expect the pH of the world’s oceans to have dropped from 8 today to 7.7 by the end of the 21st century.

Continue reading ‘Climate change threat to mussels’ shells’

Ocean acidification alters the material properties of Mytilus edulis shells

Ocean acidification (OA) and the resultant changing carbonate saturation states is threatening the formation of calcium carbonate shells and exoskeletons of marine organisms. The production of biominerals in such organisms relies on the availability of carbonate and the ability of the organism to biomineralize in changing environments. To understand how biomineralizers will respond to OA the common blue mussel, Mytilus edulis, was cultured at projected levels of pCO2 (380, 550, 750, 1000 µatm) and increased temperatures (ambient, ambient plus 2°C). Nanoindentation (a single mussel shell) and microhardness testing were used to assess the material properties of the shells. Young’s modulus (E), hardness (H) and toughness (KIC) were measured in mussel shells grown in multiple stressor conditions. OA caused mussels to produce shell calcite that is stiffer (higher modulus of elasticity) and harder than shells grown in control conditions. The outer shell (calcite) is more brittle in OA conditions while the inner shell (aragonite) is softer and less stiff in shells grown under OA conditions. Combining increasing ocean pCO2 and temperatures as projected for future global ocean appears to reduce the impact of increasing pCO2 on the material properties of the mussel shell. OA may cause changes in shell material properties that could prove problematic under predation scenarios for the mussels; however, this may be partially mitigated by increasing temperature.

Continue reading ‘Ocean acidification alters the material properties of Mytilus edulis shells’

Corals concentrate dissolved inorganic carbon to facilitate calcification

The sources of dissolved inorganic carbon (DIC) used to produce scleractinian coral skeletons are not understood. Yet this knowledge is essential for understanding coral biomineralization and assessing the potential impacts of ocean acidification on coral reefs. Here we use skeletal boron geochemistry to reconstruct the DIC chemistry of the fluid used for coral calcification. We show that corals concentrate DIC at the calcification site substantially above seawater values and that bicarbonate contributes a significant amount of the DIC pool used to build the skeleton. Corals actively increase the pH of the calcification fluid, decreasing the proportion of DIC present as CO2 and creating a diffusion gradient favouring the transport of molecular CO2 from the overlying coral tissue into the calcification site. Coupling the increases in calcification fluid pH and [DIC] yields high calcification fluid [CO32−] and induces high aragonite saturation states, favourable to the precipitation of the skeleton.

Continue reading ‘Corals concentrate dissolved inorganic carbon to facilitate calcification’

OA-ICC December calendar: 26/12 – “OA greatest hits!”

Count down the days until 2015 together with the OA-ICC! Each day of December you will find a short story on the OA-ICC news stream highlighting an ocean acidification project, effort, or resource.

Discover today’s story below: “OA greatest hits!”

Continue reading ‘OA-ICC December calendar: 26/12 – “OA greatest hits!”’


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