About these ads

Environment: Deepwater Horizon blowout may have released 250,000 tons of natural gas into the atmosphere

j

The massive Deepwater Horizon oll spill spreads a sheen across a huge section of the Gulf of Mexico in May 2010. Photo courtesy NASA.

Findings show value of long-term post-spill monitoring

Staff Report

FRISCO — Methane-munching microbes in the Gulf of Mexico may have been overwhelmed by the sheer volume of gas released during the 84-day Deepwater Horizon oil disaster in 2010.

“Most of the gas injected into the Gulf was methane, a potent greenhouse gas that contributes to global climate change, so we were naturally concerned that this potent greenhouse gas could escape into the atmosphere,” said University of Georgia researcher Samantha Joye.” Many assumed that methane-oxidizing microbes would simply consume the methane efficiently, but our data suggests that this isn’t what happened.” Continue reading

About these ads

Climate: Study shows possible pitfalls of ‘seeding’ oceans

Stimulating phytoplankton could backfire

,

,

By Summit Voice
One of the ideas that has surfaced most often is adding certain types of nutrients to the oceans to stimulate algae production in the hopes of reducing CO2. But new research shows that the law of unintended consequences always applies, perhaps even more so when experimenting with climate on a global scale.

The new study on the feeding habits of ocean microbes shows that the idea could backfire by disturbing the natural balance of ocean chemistry. After carefully studying diatoms, one type of plankton, the scientists determined that it is uses more iron that it needs for photosynthesis and storing the extra in its silica skeletons and shells. This reduces the amount of iron left over to support the carbon-eating plankton.

“Just like someone walking through a buffet line who takes the last two pieces of cake, even though they know they’ll only eat one, they’re hogging the food,” said Ellery Ingall, a professor at the Georgia Institute of Technology and co-lead author on this result.  “Everyone else in line gets nothing; the person’s decision affects these other people.” Continue reading

Fish poop a key source of nutrients in marine ecosystems

kjl

In addition to being predators, fish contribute significant amounts of nutrients to marine ecosystems. Photo courtesy NOAA.

Detailed reef study shows why it’s important to maintain healthy fish communities

By Summit Voice

FRISCO — Although fish are often thought of as predators that graze on microorganisms, plants and smaller animals, it turns out they play another crucial role in the marine ecosystem. Through excretion, they recycle the nutrients they take in, providing the fertilizer sea grass and algae need to grow.

The role of fish poop as a fertilizer for marine ecosystems had previously been overlooked, according to Jacob Allgeier, a doctoral student in the University of Georgia Odum School of Ecology, and Craig Layman, associate professor at Florida International University, who led the study in the waters of a large bay on Abaco Island, Bahamas.

The research showed that fish contribute more nutrients to their local ecosystems than any other source — enough to cause changes in the growth rates of the organisms at the base of the food web. Continue reading

Environment: Excess nutrients speed up ocean acidification

Shellfish are expected to be hit hard by ocean acidification in the coming decades. Bob Berwyn photo.

CO2 from decaying algae blooms adds to ocean woes

By Summit Voice

SUMMIT COUNTY — Runoff from agricultural and urban areas is speeding up ocean acidification in some coastal areas, adding to the woes resulting from increased concentration of atmospheric carbon dioxide.

A new study by researchers with the National Oceanic and Atmospheric Administration and the University of Georgia found that CO2 released from decaying algal blooms intensifies acidification, which is already taking a toll on shellfish populations in some areas.

Ocean acidification occurs when the ocean absorbs carbon dioxide from the atmosphere or from the breakdown of organic matter, causing a chemical reaction to make it more acidic. Species as diverse as scallops and corals are vulnerable to ocean acidification, which can affect the growth of their shells and skeletons. Continue reading

Is global warming killing football players?

Football players have also grown larger, and players with a higher body mass index appear to be more susceptible to hyperthermia

An increase in the number of football player deaths may be partially due to a warmer and more humid climate, according to a University of Georgia study.

By Summit Voice

SUMMIT COUNTY — Many Americans don’t seem convinced that global warming is a problem, but if anything might get the general population riled up, it could be a new study from the University of Georgia suggesting that climate at least plays a partial role in the recent tripling of heat-related deaths among football players.

Before 1994, there was about one death per year, since then, the number has spiked to an average of three per year, according to an analysis of weather conditions and high school and college sports data conducted by researchers from the university.

To try and pin down the cause, they developed a detailed database that included the temperature, humidity and time of day, as well as the height, weight and position for 58 football players who died during practice sessions from overheating, or hyperthermia.

The study found that, for the eastern U.S., where most deaths occurred, morning heat index values were consistently higher in the latter half of the 30-year study period. Overall, Georgia led the nation in deaths with six fatalities. Continue reading

Environment: Elkhorn coral disease traced to human waste

The human disease serratiosis is caused by the fecal coliform bacterium Serratia marcescens. When it infects coral, as in this case from Key West, Fl., it destroys the overlying coral tissue, revealing the dead, white limestone skeleton underneath. PHOTO COURTESY JAMES PORTER, UNIVERSITY OF GEORGIA.

Endangered coral can be protected with better wastewater treatment

By Bob Berwyn

SUMMIT COUNTY — By analyzing the genetics of bacteria found in partly treated sewage in the Florida Keys, researchers from Rollins College in Florida and the University of Georgia have identified human waste as the source of a pathogen that’s wiped out 88 percent of the elkhorn coral growing in Florida’s offshore reefs in the past 15 years.

The bacterium, Serratia marcescens, causes white pox disease in elkhorn coral. Because of the rapid die-off, the coral was listed under the endangered species act in 2006. Elkhorn coral across the Caribbean is affected by the same disease to varying degrees.

It’s the first time that a human pathogen has been found to cause disease in a marine invertebrate species, said University of Georgia ecology professor James Porter, one of the scientists who recently published their findings in the peer-reviewed open access journal PLoS ONE. Continue reading

Climate: Florida cold snap devastated some coral reefs

Photographs of coral colonies from Admiral Reef before (panels a, c, e) and after (panels b, d, f) the cold-water anomaly. Photographs were taken in May 2009 (before) and February 2010 (after). Coral species shown are Montastraea faveolata (a, b), Porites astreoides (c, d), and Siderastrea siderea (e, f). “After” photographs of M. faveolata and P. astreoides (panels b, d) show dead colonies, whereas S. siderea (panel f) remained alive. Pigmentation of dead M. faveolata (panel b) is due to overgrowth of the coral skeleton by cyanobacteria and filamentous algae. PHOTO COURTESY DUSTIN KEMP, UNIVERSITY OF GEORGIA.

Water temps below 54 degrees proves fatal to reef system in the Florida Keys

By Summit Voice

SUMMIT COUNTY — Amid all the concern over the impacts of rising sea temperatures to coral reefs, University of Georgia researchers have found that cold water is just as bad.

An extended cold snap in Florida in January and February 2010 killed nearly all the coral in a 200- to 300-year-old reef that had survived other extreme events, including the 1998 El Niño bleaching that damaged coral reefs across widespread regions of the world’s oceans.

During the 2010 cold snap, water temperatures at inshore reefs in the upper Florida Keys dropped below 54 degrees and remained below 64 for two weeks. The University of Georgia team had planned to sample corals at Admiral Reef, an inshore reef off Key Largo. When they arrived, they discovered that the reef, once abundant in hard and soft corals, was essentially dead.

“It was the saddest thing I’ve ever seen,” said lead researcher Dustin Kemp. “The large, reef-building corals were gone. The severe cold water appeared to kill the corals quite rapidly. Corals and their symbiotic algae have a range of stress tolerance,” Kemp said. “Some can handle moderate stress, some are highly sensitive, and some are in between. But extreme cold is just one stressor among many.” Continue reading

Follow

Get every new post delivered to your Inbox.

Join 7,623 other followers