02 May 2013: Report

A Key Experiment to Probe the
Future of Our Acidifying Oceans

In a Swedish fjord, European researchers are conducting an ambitious experiment aimed at better understanding how ocean acidification will affect marine life. Ultimately, these scientists hope to determine which species might win and which might lose in a more acidic ocean.

by peter friederici

The sea urchin is a doughty animal that can withstand cold and turbulent seas, eat almost anything, and defend itself from many predators — though not human gourmands — with its pincushion of tough spines. It’s one of the creatures that lured biologists to establish one of the world’s first marine research stations in 1877 at Kristineberg on Sweden’s west coast, for the sheltered Gullmar Fjord there is characterized by deep, cold waters that support a wide array of sea life.

That water is still being piped into laboratories to nourish aquariums filled with urchins, fish, sea stars, and other local marine fauna. But today most of the ongoing experiments in Kristineberg revolve around what biologists have taken to calling “the other CO2 problem” — the ways in which humanity’s giant, ongoing experiment in altering the world’s atmosphere is causing the oceans to become more acidic. Even the pristine-looking Gullmar Fjord — with its granite shores lined with spruce and pine trees, clear waters, and teeming populations of eiders, gulls, and many fish species — isn’t immune to that global change.

View gallery
Mesocosms Ulf Riebesell GEOMAR

Ulf Riebesell/GEOMAR
Two so-called “mesocosms” in the Gullmar Fjord near Kristineberg, Sweden.
This winter, something new appeared in the waters of the Gullmar Fjord: a floating array of ten giant, clear polyurethane bags, each supported by its own framework of floating orange pipes. Each bag amounts to a suspended test tube more than 60 feet deep and containing almost 15,000 gallons — a so-called “mesocosm” of native seawater and fjord organisms, separated for months from the fjord water just outside.

Part of a project known as the Biological Impacts of Ocean Acidification, or BIOACID, the array is the largest and longest-term study of ocean acidification attempted to date. In half of the mesocosms, a team of researchers from five European countries has lowered the pH to the level that the world’s oceans might experience in 2100. The scientists are now monitoring how generations of plankton and other organisms ranging up the food chain — including the larvae of sea urchins, cod, and herring — are reacting to that altered environment.

This summer, when the experiment comes to an end, researchers believe they will have a better idea of which species might win and which might lose in a more acidic ocean. Previous experiments by researchers from the German-based GEOMAR Helmholtz Centre for Ocean Research and elsewhere have shown that some photosynthesizing phytoplankton, such as tiny algae, benefit when more CO2 is available. Organisms higher up the food chain, then, might have more food available to them in the pH 7.8 mesocosms.

But dealing with higher levels of acidity can interfere with the ability of creatures like mollusks to build shells and can cause other physiological stress. How those factors — nutrient availability versus a changed environment — affect a variety of species is a key question being studied in the mesocosm experiment.

“The mesocosms provide the opportunity to look decades into the future to see what the oceans might look like then,” says Rolf Schwarz, an engineer at the Helmholtz Center who helped design the intricate experimental units.

The world’s oceans have been getting more acidic because they continuously absorb carbon dioxide from the atmosphere. These days, marine waters are absorbing so much carbon dioxide from the burning of
Oceans have been getting more acidic because they continuously absorb carbon dioxide from the atmosphere.
fossil fuels that it’s as if one loaded train car full of carbon were careening into the ocean every second, 24/7. Because CO2 reacts with water to form carbonic acid, the result is that ocean water has been getting more acidic. Though there’s a lot of regional variation, measurements have shown that the average pH of the ocean has declined by about 0.12 since the preindustrial era, from a starting point of 8.15 to 8.2, according to Ulf Riebesell, a biologist at the Helmholtz Centre and one of the leaders of the BIOACID project.

That might not seem like a big deal, were it not for two factors. First, there’s the alarming and accelerating trajectory that civilization is on: According to climatological models, at humanity’s current rate of carbon emissions the ocean’s pH would decline to 7.8 by around the year 2100. That would be the most acidic ocean in at least 300 million years, and the pH level would have changed in a much shorter period than is recorded in paleoclimatological records, according to a 2012 study led by paleoclimatologist Bärbel Hönisch of Columbia University’s Lamont-Doherty Earth Observatory.

“Comparable changes in environmental conditions like today’s acidification led to mass extinctions a number of times in the past, even though those changes took place ten to a hundred times more slowly than today,” says Riebesell.

Second, there’s been extensive laboratory work showing that many marine organisms don’t respond well to the more acidic conditions. At a pH of about 7.8, many shelled organisms dissolve. Some fish larvae grow more slowly, and clownfish and sea snails display aberrant behavior, such as swimming toward a predator. The impacts of acidification have even received attention from aquaculturists and epicurians: In the Pacific Northwest, reproductive failure at some oyster farms has been attributed to increased acidity in the waters.

It’s this plethora of documented, negative effects that led Riebesell and his team to develop the experimental mesocosms.

View gallery
Mesocosms Ulf Riebesell GEOMAR

Yves Gladu/EPOCA
A view from below of a mesocosm, which holds water and organisms from the fjord.
“It’s one thing to look at this in the lab, organism for organism,” he says. “But we really want to observe ecosystems directly, with all the factors that belong to them — predation, competition, and so on. We want to know how food webs react, not only single organisms.”

But monitoring food webs over the lifespan of fish or sea urchins, which take several years to reach maturity, would take too long and would be too costly. For that reason, Riebesell designed the mesocosm experiment to focus on many generations of plankton and other tiny ocean organisms, which mature far more quickly and will also be affected by increases in ocean acidity.

It’s an intriguing idea, but not an easy one to carry out. For repeatability and comparison, the researchers wanted ten mesocosms — five to be filled with ocean water to which additional CO2 would be added, and five controls. The Helmholtz team has previously installed and monitored mesocosms at locations in Spitsbergen, Norway, and Finland since 2010, but only for relatively short periods. This year, in order to capture the spring phytoplankton bloom — an explosion of photosynthesis that is the foundation of the marine food web — the researchers had to install all this equipment in late January, when the fjord is often choked with floating pack ice.

For a while, thickly clad researchers in an aluminum boat had to patrol the array to prevent ice from puncturing the bags. Then the bags began to sink and leak because they were filled at the height of winter, a time when the seawater in the region is particularly saline, which adds weight. Researchers had to refill the mesocosms and install additional buoys.

To make half of the mesocosms acidic, the research team poured in a few hundred liters of fjord water to which a great deal of CO2 had been added, creating a pH of 7.8 inside the floating bags. Since mid-February, the
As sea urchins adapt to more acidic water, they might lose the ability to cope with other stresses.
scientists have been taking samples every two days of the chambers’ water and of the debris that accumulates at their base. Dead plankton, waste material, and other organic matter make up this smelly muck. By analyzing both the water and the bottom debris, the researchers can tell what types of plankton and other organisms are living in each mesocosm and their relative proportions — an indication of how different organisms might fare in more acidic conditions.

By mid-April they’d watched as phytoplankton bloomed and were in turn eaten by an array of tiny grazers. In the next two months, they are going to observe how succeeding generations of plankton interact with one another. And they’ll see how those changes ripple up the food chain to the larvae of higher-level animals, such as sea urchins and herring.

If Riebesell and his colleagues find differences in the community makeup between the control and high-CO2 units, that will provide insights into how evolution might allow ecosystems to adapt — and which species might flourish, and which might suffer.

The researchers will be comparing notes with Sam Dupont, a researcher at the University of Gothenburg who is based at the Kristineberg station. He has conducted a number of laboratory studies on sea urchins and other shell-forming organisms, and has been able to show that urchin larvae do have some ability to deal with more acidic water. At a cellular level, they can shield their vulnerable calcareous skeletons from overly acidic water. But there’s a cost.

“When the larvae are raised in low-pH water they have less energy left for growth, because they need more energy to deal with the stress,” he says. “They grow slower. That’s a big problem for larvae, because the more time they spend free in the water the more they’re exposed to predators.” Urchins are much more susceptible to predation as free-swimming larvae
‘We might get an idea whether adaptation is a possibility,’ says one scientist.
than after they have built their prickly outer skeletons and turned into adults.

In a recent study, Indiana University biologist Melissa Pespeni also exposed sea urchin larvae to high CO2 conditions. She found that the species has so much genetic diversity that some individuals can survive just fine. But as urchins adapt to more acidic water, they might lose the ability to deal with other environmental stressors, such as pollution or nutrient runoff.

What’s needed, Pespeni says, are long-term studies focusing on entire food webs — precisely the kind of experiment being carried out in the mesocosms of the Gullmar Fjord. Dupont agrees, noting that there’s a great benefit to having his lab experiments taking place alongside the work in the fjord. “It’s kind of a synergy between the lab work, where we can control every variable, and the crazy, chaotic work out in the ecosystem,” he says. “They’re really complementary.”

The mesocosms are scheduled to keep serving as floating aquariums at least until July, by which time the researchers expect dozens of generations of short-lived plankton to have flourished inside. Riebesell hopes that measurements of this generational progression will provide valuable insights. “We won’t be able to learn exactly what the oceans will look like in a hundred years,” says Riebesell. “But we might get an idea whether the concept of adaptation is a possibility.”

POSTED ON 02 May 2013 IN Oceans Policy & Politics Sustainability Water Central & South America Europe 

COMMENTS


It is important to save the whales, because the feces of whales are rich in iron. This fertilizes phytoplankton, which can absorb 400,000 pounds of carbon from the atmosphere. Thus cut down on ocean acidification.

Posted by Tim Upham on 02 May 2013


I live there and I spend a lot of time fishing in the area. Many fjords and bays (vik) are polluted, they are in an anoxia states, meaning there is not enough oxygen for the fish to stay in. The dying brown algae are now covered by thin filaments looking like this
http://www.havet.nu/?d=31

And in the summer comes armadas of jelly fishes...

The cod has already nearly disappeared from this coast, what is going to be next. I pray that the sea trout will survive because this is the most fascinating fish i have ever fished... They have increased recently in number thanks to work on stream (limestone added in streams and lake), and a constant inequal fight against electricity companies...But the increase is still very fragile. given the area that are affected by anoxia and the encroaching urbanisation that has transformed small streams into sewage (literally).

The coast is also littered with plastic objects and they have measured that this is more or less a soup of platic microparticle....

People live in little bubble, from car, TV and work. They have no memory of what was the world 20 years before. They are not seing that the whole thing is collapsing very fast.
I wonder if it makes any sense to measure these things when hundreds of parameters are simultaneously modified so rapidly by fast growing human societies.

Posted by kervennic on 05 May 2013


POST A COMMENT

Comments are moderated and will be reviewed before they are posted to ensure they are on topic, relevant, and not abusive. They may be edited for length and clarity. By filling out this form, you give Yale Environment 360 permission to publish this comment.

Name 
Email address 
Comment 
 
Please type the text shown in the graphic.


peter friedericiABOUT THE AUTHOR
Peter Friederici is a science writer and assistant professor of environmental journalism at Northern Arizona University. He is the author of the book, People and Places on the Front Lines of Conservation. His writing has appeared in Audubon magazine, High Country News, and other publications.

 
 

RELATED ARTICLES


Using Ocean Robots to Unlock
Mysteries of CO2 and the Seas

Marine phytoplankton are vital in absorbing ever-increasing amounts of CO2 from the atmosphere. In a Yale Environment 360 interview, researcher Tracy Villareal explains how he is using remotely operated robots to better understand how this process mitigates climate change.
READ MORE

In Japan, Captive Breeding
May Help Save the Wild Eel

As eel populations plummet worldwide, Japanese scientists are racing to solve a major challenge for aquaculture — how to replicate the life cycle of eels in captivity and commercially produce a fish that is a prized delicacy on Asian dinner tables.
READ MORE

New Initiatives to Clean Up
The Global Aquarium Trade

An estimated 30 million fish and other creatures are caught annually to supply the home aquarium market, taking a toll on some reef ecosystems. Now conservationists are working to improve the industry by ending destructive practices and encouraging aquaculture.
READ MORE

No Refuge: Tons of Trash Covers
The Remote Shores of Alaska

A marine biologist traveled to southwestern Alaska in search of ocean trash that had washed up along a magnificent coast rich in fish, birds, and other wildlife. He and his colleagues found plenty of trash – as much as a ton of garbage per mile on some beaches.
READ MORE

How Mussel Farming Could
Help to Clean Fouled Waters

Along the shores of New York Harbor, scientists are investigating whether this ubiquitous bivalve can be grown in urban areas as a way of cleansing coastal waters of sewage, fertilizers, and other pollutants.
READ MORE

 

MORE IN Reports


A Public Relations Drive to
Stop Illegal Rhino Horn Trade

by mike ives
Conservation groups are mounting campaigns to persuade Vietnamese consumers that buying rhino horn is decidedly uncool. But such efforts are likely to succeed only as part of a broader initiative to crack down on an illicit trade that is decimating African rhino populations.
READ MORE

On Fracking Front, A Push
To Reduce Leaks of Methane

by roger real drouin
Scientists, engineers, and government regulators are increasingly turning their attention to solving one of the chief environmental problems associated with fracking for natural gas and oil – significant leaks of methane, a potent greenhouse gas.
READ MORE

Scientists Focus on Polar Waters
As Threat of Acidification Grows

by jo chandler
A sophisticated and challenging experiment in Antarctica is the latest effort to study ocean acidification in the polar regions, where frigid waters are expected to feel most acutely the ecological impacts of acidic conditions not seen in millions of years.
READ MORE

On Ravaged Tar Sands Lands,
Big Challenges for Reclamation

by ed struzik
The mining of Canada’s tar sands has destroyed large areas of sensitive wetlands in Alberta. Oil sands companies have vowed to reclaim this land, but little restoration has occurred so far and many scientists say it is virtually impossible to rebuild these complex ecosystems.
READ MORE

A New Leaf in the Rainforest:
Longtime Villain Vows Reform

by rhett butler
Few companies have done as much damage to the world’s tropical forests as Asia Pulp & Paper. But under intense pressure from its customers and conservation groups, APP has embarked on a series of changes that could significantly reduce deforestation in Indonesia and serve as a model for forestry reform.
READ MORE

In a Host of Small Sources,
Scientists See Energy Windfall

by cheryl katz
The emerging field of “energy scavenging” is drawing on a wide array of untapped energy sources­ — including radio waves, vibrations created by moving objects, and waste heat from computers or car exhaust systems — to generate electricity and boost efficiency.
READ MORE

Life on Mekong Faces Threats
As Major Dams Begin to Rise

by joshua zaffos
With a massive dam under construction in Laos and other dams on the way, the Mekong River is facing a wave of hydroelectric projects that could profoundly alter the river’s ecology and disrupt the food supplies of millions of people in Southeast Asia.
READ MORE

As Fracking Booms, Growing
Concerns About Wastewater

by roger real drouin
With hydraulic fracturing for oil and gas continuing to proliferate across the U.S., scientists and environmental activists are raising questions about whether millions of gallons of contaminated drilling fluids could be threatening water supplies and human health.
READ MORE

In Developing World, A Push to
Bring E-Waste Out of Shadows

by mike ives
For decades, hazardous electronic waste from around the world has been processed in unsafe backyard recycling operations in Asia and Africa. Now, a small but growing movement is seeking to provide these informal collectors with incentives to sell e-waste to advanced recycling facilities.
READ MORE

Growing Insects: Farmers Can
Help to Bring Back Pollinators

by richard conniff
With a sharp decline in pollinating insects, farmers are being encouraged to grow flowering plants that can support these important insects. It’s a fledgling movement that could help restore the pollinators that are essential for world food production.
READ MORE


e360 digest
Yale
Yale Environment 360 is
a publication of the
Yale School of Forestry
& Environmental Studies
.

SEARCH e360



Donate to Yale Environment 360
Yale Environment 360 Newsletter

CONNECT

Twitter: YaleE360
e360 on Facebook
Donate to e360
View mobile site
Bookmark
Share e360
Subscribe to our newsletter
Subscribe to our feed:
rss


ABOUT

About e360
Contact
Submission Guidelines
Reprints

E360 en Español

Universia partnership
Yale Environment 360 articles are now available in Spanish and Portuguese on Universia, the online educational network.
Visit the site.


DEPARTMENTS

Opinion
Reports
Analysis
Interviews
Forums
e360 Digest
Podcasts
Video Reports

TOPICS

Biodiversity
Business & Innovation
Climate
Energy
Forests
Oceans
Policy & Politics
Pollution & Health
Science & Technology
Sustainability
Urbanization
Water

REGIONS

Antarctica and the Arctic
Africa
Asia
Australia
Central & South America
Europe
Middle East
North America

e360 PHOTO GALLERY

“Peter
Photographer Peter Essick documents the swift changes wrought by global warming in Antarctica, Greenland, and other far-flung places.
View the gallery.

e360 MOBILE

Mobile
The latest
from Yale
Environment 360
is now available for mobile devices at e360.yale.edu/mobile.

e360 VIDEO

Warriors of Qiugang
The Warriors of Qiugang, a Yale Environment 360 video that chronicles the story of a Chinese village’s fight against a polluting chemical plant, was nominated for a 2011 Academy Award for Best Documentary (Short Subject). Watch the video.


header image
Top Image: aerial view of Iceland. © Google & TerraMetrics.

e360 VIDEO

Colorado River Video
In a Yale Environment 360 video, photographer Pete McBride documents how increasing water demands have transformed the Colorado River, the lifeblood of the arid Southwest. Watch the video.

 

OF INTEREST



Yale