Archive for September, 2010

2 faculty positions in estuarine and marine processes (rank open)

University of Maryland Center for Environmental Science
Chesapeake Biological Laboratory

Target date for receipt of applications: December 20, 2010

We invite applications for two tenure-track faculty positions in marine biogeochemistry and marine / estuarine ecology that will complement and enhance our existing programs in biogeochemistry, ecology, fisheries science and ecotoxicology. We seek candidates who conduct trans-disciplinary research in cross-cutting areas such as the cycling and transformations of organic matter within and among marine and estuarine systems, including biogeochemical interactions in sediments.
Continue reading ‘2 faculty positions in estuarine and marine processes (rank open)’

Oceans acidify much faster than ever before in Earth’s history

bioacid

Conference: More than 200 scientists from all over Europe discuss increasing ocean acidification

For four days the topic of ocean acidification will be the focus of marine and polar research. The Alfred Wegener Institute for Polar and Marine Research in the Hemholtz Association is hosting the conference and expects more than 200 scientists from all over Europe at the Conference Center Bremerhaven.

The greenhouse gas carbon dioxide not only leads to global climate warming, but also to increasing acidification of the oceans. Next week scientists will discuss the most recent results on ocean acidification at the first joint meeting of the three large coordinated projects, EPOCA (European Project on Ocean Acidification), the German project BIOACID (Biological Impacts of Ocean ACIDification) and UK project UKOARP (UK Ocean Acidification Research Program).
Continue reading ‘Oceans acidify much faster than ever before in Earth’s history’

Climate change effects on fishes and fisheries: towards a cause-and-effect understanding

Ongoing climate change is predicted to affect individual organisms during all life stages, thereby affecting populations of a species, communities and the functioning of ecosystems. These effects of climate change can be direct, through changing water temperatures and associated phenologies, the lengths and frequency of hypoxia events, through ongoing ocean acidification trends or through shifts in hydrodynamics and in sea level. In some cases, climate interactions with a species will also, or mostly, be indirect and mediated through direct effects on key prey species which change the composition and dynamic coupling of food webs. Thus, the implications of climate change for marine fish populations can be seen to result from phenomena at four interlinked levels of biological organization: (1) organismal-level physiological changes will occur in response to changing environmental variables such as temperature, dissolved oxygen and ocean carbon dioxide levels. An integrated view of relevant effects, adaptation processes and tolerance limits is provided by the concept of oxygen and capacity-limited thermal tolerance (OCLT). (2) Individual-level behavioural changes may occur such as the avoidance of unfavourable conditions and, if possible, movement into suitable areas. (3) Population-level changes may be observed via changes in the balance between rates of mortality, growth and reproduction. This includes changes in the retention or dispersion of early life stages by ocean currents, which lead to the establishment of new populations in new areas or abandonment of traditional habitats. (4) Ecosystem-level changes in productivity and food web interactions will result from differing physiological responses by organisms at different levels of the food web. The shifts in biogeography and warming-induced biodiversity will affect species productivity and may, thus, explain changes in fisheries economies. This paper tries to establish links between various levels of biological organization by means of addressing the effective physiological principles at the cellular, tissue and whole organism levels.
Continue reading ‘Climate change effects on fishes and fisheries: towards a cause-and-effect understanding’

UAB researchers receive grant to study Antarctic ocean acidification

The National Science Foundation awarded a $625,499 grant to the University of Alabama at Birmingham to study the effects of ocean acidification and rising sea surface temperatures on shallow-water benthic organisms in Antarctica on September 20, 2010.

This is a three year study that resulted from the work of James B McClintock (Department of Biology – Physiology & Ecology of Aquatic & Marine Invertebrates), Charles Amsler (marine algal ecophysiologist from the UAB Biology Department), and Robert Angus (Professor Biology – Endocrine disrupters in aquatic models).
Continue reading ‘UAB researchers receive grant to study Antarctic ocean acidification’

Acidification of oceans may contribute to global declines of shellfish, study by Stony Brook scientists concludes

The acidification of the Earth’s oceans due to rising levels of carbon dioxide (CO2) may be contributing to a global decline of clams, scallops and other shellfish by interfering with the development of shellfish larvae, according to two Stony Brook University scientists, whose findings are published online and in the current issue of PNAS (Proceedings of the National Academy of Sciences of the United States of America) entitled, “Effects of past, present, and future ocean carbon dioxide concentrations on the growth and survival of larval shellfish.”
Continue reading ‘Acidification of oceans may contribute to global declines of shellfish, study by Stony Brook scientists concludes’

Ocean acidification: a millennial challenge

During recent decades, Earth system research has provided overwhelming evidence that climate change, with disastrous consequences, will result from unbridled anthropogenic emissions of greenhouse gases. It is well accepted among climate scientists that these emissions, especially of CO2, may force the planet to warm by up to seven degrees C by the end of the century. During recent years, however, a second comparably dangerous consequence of steadily increasing atmospheric carbon dioxide levels has received growing attention, namely the acidification of the oceans. Here we discuss its potential effects on marine biogeochemistry and review the recent literature on this issue. Calcifying organisms such as corals, pteropods, coccolithophorides and foraminifera are among the species that will suffer most from unabated ocean acidification.
Continue reading ‘Ocean acidification: a millennial challenge’

Acclimation and adaptation to ocean acidification of key ecosystem components in the California Current System

Intellectual Merit. This project will investigate the impacts of ocean acidification (OA) on two ecologically important, calcification-dependent marine invertebrates in relation to local-to-coastal variation in carbonate chemistry (e.g., pH and aragonite saturation) in the California Current Large Marine Ecosystem (CCLME). An interdisciplinary team of investigators with expertise in physical and chemical oceanography, marine ecology, biochemistry, molecular physiology, and molecular genetics will carry out an integrated, lab and field, multi-site investigation of the ecological, physiological, and evolutionary responses of sea urchins and mussels to spatial and temporal variation in OA. The research will take place in the context of a mosaic of variable oceanography, including recently documented latitudinal variation in carbonate chemistry along the upwelling-dominated US west coast. Variation in upwelling regimes from Washington to southern California generates spatial and temporal gradients in concentration of CO2 that shoal to surface waters during upwelling events, extending shoreward into the inner shelf region. Through well-known chemical pathways, influxes of CO2 cause present-day declines in pH in coastal ecosystems that are lower than values forecast for the ocean in general in the year 2200. Lower than “normal” pH can influence organisms by altering intracellular biochemistry, and especially, for calcification-dependent marine organisms, interfere with formation of hard parts as the aragonite saturation state falls near or below 1.0. Because calcifiers in the upwelling-dominated CCLME have historically experienced persistent regional variation in pH, populations are likely differentially acclimatized and/or adapted to a variable carbonate chemistry environment. The new challenge to these organisms is that with global change and the resulting increase in seawater CO2, they already may be close to their acclimatization or adaptational capacity, and thus may have limited ability to respond to additional increases in CO2. It is this challenge, the mechanistic ability of calcifying invertebrates to acclimate or adapt to increasing CO2 and aragonite saturation states < 1.0 that we address here.
Continue reading ‘Acclimation and adaptation to ocean acidification of key ecosystem components in the California Current System’

CO2-induced seawater acidification affects physiological performance of the marine diatom Phaeodactylum tricornutum

CO2/pH perturbation experiments were carried out under two different pCO2 levels (39.3 and 101.3 Pa) to evaluate effects of CO2-induced ocean acidification on the marine diatom Phaeodactylum tricornutum. After acclimation (>20 generations) to ambient and elevated CO2 conditions (with corresponding pH values of 8.15 and 7.80, respectively), growth and photosynthetic carbon fixation rates of high CO2 grown cells were enhanced by 5% and 12%, respectively, and dark respiration stimulated by 34% compared to cells grown at ambient CO2. The half saturation constant (Km) for carbon fixation (dissolved inorganic carbon, DIC) increased by 20% under the low pH and high CO2 condition, reflecting a decreased affinity for HCO3 or/and CO2 and down-regulated carbon concentrating mechanism (CCM). In the high CO2 grown cells, the electron transport rate from photosystem II (PSII) was photoinhibited to a greater extent at high levels of photosynthetically active radiation, while non-photochemical quenching was reduced compared to low CO2 grown cells. This was probably due to the down-regulation of CCM, which serves as a sink for excessive energy. The balance between these positive and negative effects on diatom productivity will be a key factor in determining the net effect of rising atmospheric CO2 on ocean primary production.
Continue reading ‘CO2-induced seawater acidification affects physiological performance of the marine diatom Phaeodactylum tricornutum’

Biogeosciences special issue “The Ocean in a High-CO2 World”

The publication of papers from the special issue of Biogeosciences from the Second Symposium on The Ocean in a High-CO2 World, held in Monaco in 2008, began in 2009. The last papers have now been completed and final versions have been accepted for publication.
Continue reading ‘Biogeosciences special issue “The Ocean in a High-CO2 World”’

Some North Atlantic pollution falls, new threats loom

Efforts to clean up and protect the North East Atlantic have made some progress since 2000 but new threats are looming such as ocean acidification linked to climate change, a study said on Thursday.

The report, by the OSPAR Commission that groups 15 European nations and covers an area from the North Pole to the Azores, said there had been advances in reducing oil spills, discharges from nuclear installations and some hazardous wastes.

But many goals set in 2000 such as stopping a loss of biological diversity and over-fishing had not been met, according to the report, presented to environment ministers from the 15 nations in Bergen, Norway.

“There are clear signs of improvement in the North-East Atlantic but the loss of biodiversity has not yet been halted, with fishing and other human activities needing careful management,” it said.

“Ocean acidification and the emerging impacts of climate change cause serious concern,” it added. Acidification undermines the ability of creatures such as shellfish, crabs or lobsters to build their protective shells.
Continue reading ‘Some North Atlantic pollution falls, new threats loom’


Subscribe to the RSS feed

Powered by FeedBurner

Follow AnneMarin on Twitter

Blog Stats

  • 1,400,694 hits

OA-ICC HIGHLIGHTS

Ocean acidification in the IPCC AR5 WG II

OUP book

Archives