Published 10 December 2016
The Science and Technology Committee is today launching a new inquiry on Ocean Acidification – the first full parliamentary inquiry on the often ignored environmental issue. Launching the inquiry the Chair of the Committee Stephen Metcalfe MP said:
“Climate change often overshadows other environmental issues, but it is not the only problem being caused by rising levels of carbon dioxide. CO2 is also being absorbed by the oceans, making our oceans gradually more acidic.
“More research is needed to understand the implications of this ocean acidification and the trends in ocean pH levels. But a reduction in the sea’s alkalinity could have damaging impacts on coral reefs and shell-forming sea creatures. That is because the calcium carbonate in shells and coral can dissolve in acid.
“About seventy per cent of the Earth’s surface is covered by oceans but our scientific understanding of the marine environment is patchy at best. Now that the UK’s five year Ocean Acidification Research Programme has ended, we are launching the first parliamentary inquiry on this concerning topic to examine what has been learned and make recommendations to Government.
“Should we be worried about the consequences of ocean acidification for the food chain and the marine economy? How bad is the problem? And what policy interventions should the Government be bringing forward to tackle it? These are all questions that we will address in this inquiry.”
Continue reading ‘First parliamentary inquiry launched on ocean acidification’
Published 9 December 2016
Tags: chemistry, methods
As research into the biotic effects of ocean acidification has increased, the methods for simulating these environmental changes in the laboratory have multiplied. Here we describe the atmospheric carbon control simulator (ACCS) for the maintenance of plankton under controlled pCO2 conditions, designed for species sensitive to the physical disturbance introduced by bubbling of cultures and for studies involving trophic interaction. The system consists of gas mixing and equilibration components, coupled with large volume atmospheric simulation chambers. These chambers allow gas exchange to counteract the changes in carbonate chemistry induced by the metabolic activity of the organisms. The system is relatively low cost, very flexible, and when used in conjunction with semi-continuous culture methods, increases the density of organisms kept under realistic conditions, increases the allowable time interval between dilutions, and/or decreases the metabolically driven change in carbonate chemistry during these intervals. It accommodates a large number of culture vessels, which facilitate multi-trophic level studies and allow the tracking of variable OA responses within and across plankton populations. It also includes components that increase the reliability of gas mixing systems using mass flow controllers.
Continue reading ‘Technical Note: A minimally-invasive experimental system for pCO2 manipulation in plankton cultures using passive gas exchange (Atmospheric Carbon Control Simulator)’
Published 8 December 2016
Tags: chemistry, field, North Pacific
Rapid changes, including warming and freshening, are occurring in coastal marine ecosystems worldwide. These environmental changes have the potential to alter ecosystem energetics by influencing availability of food sources and organism physiology. We investigated the influence of oceanographic variability on food availability and quality to benthic and pelagic suspension-feeders using detailed observations of phytoplankton, particulate organic matter (POM) detritus, and diverse biomarkers (fatty acids and carbon, nitrogen, and sulfur stable isotopes) along a salinity gradient in the San Juan Archipelago, Washington, U.S.A. We tested the hypothesis that freshwater input from riverine discharge would cause significant changes to oceanographic conditions and reduce food quality (indicated by essential fatty acids; EFA), owing to greater contribution of terrestrial organic matter. Contrary to our expectations, availability of high-quality marine-derived POM increased with freshwater input (reduced salinity). Phytoplankton biomass and biomarker composition responded to oceanographic change similarly across tidal and seasonal scales. Using a meta-analysis spanning a range of spatial and temporal scales, we found that chlorophyll a, temperature, dissolved oxygen (DO) and pH were consistently and significantly higher at reduced salinity. The increase of DO and pH corresponding to higher phytoplankton biomass in low salinity water signifies an important feedback of biological activity on seawater chemistry. This analysis supports the use of salinity as an indicator of processes controlling food availability and oceanographic conditions in this region. Collectively, these results highlight the importance of ecosystem connectivity in coastal environments and produce hypotheses for expected changes related to altered river discharge dynamics.
Continue reading ‘Improved marine-derived POM availability and increased pH related to freshwater influence in an inland sea’
Published 8 December 2016
Program , Science
Dear Ocean Carbon Scientists,
Data management activities for the ocean component of the Carbon Dioxide Information Analysis Center (CDIAC-Oceans) at Oak Ridge National Laboratory (ORNL) have recently stopped and this letter provides information on steps being taken to minimize the impact of this stoppage on the oceanographic community. Data, numerical data packages (NDPs), data synthesis product pages, and utilities (such as CO2SYS) at CDIAC-Oceans will continue to be accessible through ORNL until September 30, 2017 when the entire CDIAC will fully cease operations.
Effective January 1, 2017, Alex Kozyr will become an Affiliate Staff member for NOAA’s National Centers for Environmental Information (NCEI) to support ocean carbon data management and provide customer support similar to what he has done at CDIAC. He will also assist in the transition of ocean carbon data management to NCEI.
NCEI is now archiving CDIAC’s ocean carbon data and will complete the transfer prior to CDIAC’s closure. A plan to integrate the content of CDIAC’s ocean carbon web sites and services is being developed, with a target completion date of March 31, 2017.
For more details on the transition and how to submit and access ocean carbon data in the future, please check out this page: http://www.nodc.noaa.gov/oceanacidification/ocads/transition.html.
Continue reading ‘Carbon Dioxide Information Analysis Center (CDIAC-Oceans) ceases operation, all activities to transition to NOAA’
Published 8 December 2016
Closing date for applications: 12 January 2017!
We are looking for a PDRA to create new explanatory models of environmental drivers of biodiversity trends in the deep North Atlantic Ocean, and assess Good Environmental Status (GES) as part of the European ATLAS project . The project will progress research on the biodiversity of Scotland’s seamounts, banks, continental slope and shelf but also at a site in the High Seas. The project will analyse both video/stills and faunal samples to create explanatory and spatially explicit statistical models that explain trends in deep ocean biodiversity across gradients in oceanography, bathymetry, geology and carbon flux. ATLAS is a multidisciplinary trans-Atlantic collaboration between Europe, Canada and the USA, and aims to develop an adaptive ecosystem-based approach to marine spatial management in the deep North Atlantic. This post is full time, fixed term for 36 months and is available from 1 February 2017; or as soon as possible thereafter.
- PhD project “Biogeographical patterns in the deep ocean: environmental, biological, and historical drivers in the North Atlantic” (link)
- PhD project “Physiology and carbon cycling of North Atlantic coral ecosystems in a changing ocean” (link)
Knowledge, skills and experience needed for the job
• PhD (or near completion) in Aquatic, Biological, or Zoological Sciences
• Proven skills in microscopy and benthic taxonomy
• Strong analytical experience in ArcGIS and R
• Excellent written and oral communication skills in English, team-working and interpersonal skills
• Previous experience of dissemination and publication of personal and/or research team’s findings
Continue reading ‘Postdoctoral research associate in deep-sea biodiversity, University of Edinburgh’
Objective: Increasing atmospheric CO2 concentration are causing changes to the seawater carbonate chemistry, lowering the pH and we study potential impacts of these changes at the molecular level in a non-calcifying, marine polychaete species Platynereis dumerilii.
Methods: We investigate the relative expression of carbonic anhydrase (CA), Na+/H+ exchangers (NHE), and calmodulin (CaM) genes from P. dumerilii under acidified seawater conditions (pH 7.8) induced by CO2 using qPCR.
Results: mRNA expression of CA in the CO2-induced worms was significantly up-regulated at low pH conditions (pH 7.8, 1h), suggesting changes in acid-base balance. In contrast, the expression of NHE and CaM showed no significant change. In addition, we compare these results to a previous study using inorganic acid (HCl)-induced pH changes.
Conclusions: Results suggest that carbonate chemistry has an impact on gene expression that differs from pH-associated change. To our knowledge, this is the first study that compares low pH exposure experiments using HCl and CO2 as the inducing agents.
Continue reading ‘Short-term effects of CO2-induced low pH exposure on target gene expression in Platynereis dumerilii’
Published 7 December 2016
Tags: abundance, Arctic, biogeochemistry, biological response, BRcommunity, community composition, laboratory, light, multiple factors, otherprocess, photosynthesis, phytoplankton, prokaryotes, ptorists
In an experimental assessment of the potential impact of Arctic Ocean acidification on seasonal phytoplankton blooms and associated dimethylsulfide (DMS) dynamics, we incubated water from Baffin Bay under conditions representing an acidified Arctic Ocean. Using two light regimes simulating under-ice/ subsurface chlorophyll maxima (low light; Low PAR and no UVB) and ice-free (high light; High PAR + UVA + UVB) conditions, water collected at 38 m was exposed over 9 days to 6 levels of decreasing pH from 8.1 to 7.2. A phytoplankton bloom dominated by the centric diatoms Chaetoceros spp. reaching up to 7.5 µg chlorophyll a L−1 took place in all experimental bags. Total dimethylsulfoniopropionate (DMSPT) and DMS concentrations reached 155 nmol L−1 and 19 nmol L−1, respectively. Under both light regimes, chlorophyll a and DMS concentrations decreased linearly with increasing proton concentration at all pH tested. Concentrations of DMSPT also decreased but only under high light and over a smaller pH range (from 8.1 to 7.6). In contrast to nanophytoplankton (2–20 µm), picophytoplankton (≤ 2 µm) was stimulated by the decreasing pH. We furthermore observed no significant difference between the two light regimes tested in term of chlorophyll a, phytoplankton abundance/ taxonomy, and DMSP/ DMS net concentrations. These results show that OA could significantly decrease the algal biomass and inhibit DMS production during the seasonal phytoplankton bloom in the Arctic, with possible consequences for the regional climate.
Continue reading ‘Impact of ocean acidification on Arctic phytoplankton blooms and dimethylsulfide production under simulated ice-free and under-ice conditions’