Archive for February, 2017

Microplastics article in Savannah Morning News

February 20, 2017
Students from Pierce County Middle School sort through the results of a trawl as part of an education program at the UGA Marine Education Center and Aquarium.

Students from Pierce County Middle School sort through the results of a trawl as part of an education program at the UGA Marine Education Center and Aquarium.

Reporter Mary Landers wrote a very nice article about Dr. Jay Brandes’s research into microplastic and microfiber pollution on the Georgia coast.

http://savannahnow.com/news/2017-02-19/skidaway-researchers-track-plastic-fibers-coastal-food-chain

Skidaway Institute focus of public radio feature

February 15, 2017

UGA Skidaway Institute external affairs manager was interviewed by Georgia Public Broadcasting about the institute and its work.

http://www.gpb.org/blogs/community/2017/02/14/skidaway-institute-of-oceanography-diving-marine-science-savannah

Tiny but voracious marine organism studied — video

February 8, 2017

Tiny but all-consuming marine organism focus of UGA Skidaway Institute study

February 8, 2017
Marc Frischer

Marc Frischer

Doliolids are tiny marine animals rarely seen by humans outside a research setting, yet they are key players in the marine ecosystem, particularly in the ocean’s highly productive tropical and subtropical continental margins, such as Georgia’s continental shelf. University of Georgia Skidaway Institute of Oceanography scientist Marc Frischer is leading a team of researchers investigating doliolids’ role as a predator in the marine food web.

Doliolids are small, barrel-shaped gelatinous organisms that can grow as large as ten millimeters, or about four tenths of an inch. They are not always present in large numbers, but when they bloom they can restructure the marine food web, consuming virtually all the algae and much of the smaller zooplankton.

A doliolid with a cluster of juvenile doliolids on its tail. Actual size is approximately three millimeters, or one eighth inch.

A doliolid with a cluster of juvenile doliolids on its tail. Actual size is approximately three millimeters, or one eighth inch.

“The goal of this particular study is to find out what the doliolids are eating quantitatively,” Frischer said. “This is so we can understand where they fit in the food web.”

Scientists know from laboratory experiments what doliolids are capable of eating, but they don’t know what they actually do eat in the wild. They are capable of eating organisms as small as bacteria all the way up to much larger organisms.

“What they are eating and how much are they eating from the smorgasbord that is available to them, that is the question,” Frischer said. “We are investigating how much of those different prey types they are really eating out there across the seasons.”

The project involves intensive field work, including 54 days of ship time on board UGA Skidaway Institute’s Research Vessel Savannah. During the cruises they conduct trawls using special plankton nets to collect the doliolids. They also collect water samples to understand the conditions where the doliolids thrive.

Graduate students Lauren Lamboley and Nick Castellane deploy a plankton net from the Research Vessel Savannah.

Graduate students Lauren Lamboley and Nick Castellane deploy a plankton net from the Research Vessel Savannah.

“We take the doliolids and the water samples back to the laboratory, and that is where the magic begins,” Tina Walters, Frischer’s laboratory manager said.

Because the animals are gelatinous and very delicate, the researchers cannot use classical microscopic techniques to dissect the animals and analyze their gut content. Instead they extract DNA from the animals’ gut and use sequence-based information to determine what the doliolid ate.

“We go through a process called quantitative PCR,” Walters said. “So even though we can’t see the prey in a doliolid’s gut, because the prey have unique DNA sequences, we can identify and quantify them using a molecular approach.”

The three-year project is funded by a $725,000 grant from the National Science Foundation and will run until February 2018. Frischer’s collaborator on the project is Deidre Gibson from Hampton University. Gibson received her Ph.D. from the University of Georgia in 2000, and did much of her graduate research at Skidaway Institute with Professor Gustav Paffenhöfer.  In addition to Walters, Savannah State University graduate student Lauren Lamboley is part of the team, along with a number of students at Hampton University. Several undergraduate research interns have also participated in the project, gaining hands-on research experience. Frischer is also working with the Institute for Interdisciplinary STEM Education at Georgia Southern University to engage K-12 teachers by inviting them to participate in the research cruises.

UGA Skidaway Institute research paper selected for Research Spotlight

February 3, 2017

 

Skidaway Institute's Aron Stubbins

Skidaway Institute’s Aron Stubbins

A research paper by University of Georgia Skidaway Institute of Oceanography scientist Aron Stubbins has been selected by the Journal of Geophysical Research-Biogeosciences to be featured as a Research Spotlight on the journal’s website and in the magazine Eos. Research Spotlights summarize the the best accepted articles for the Earth and space science community.

Stubbins’s paper, titled “Low photolability of yedoma permafrost dissolved organic carbon,” followed-up on earlier research into a massive store of carbon—relics of long-dead plants and other living things—preserved within ancient Arctic permafrost. That research showed the long-frozen permafrost is thawing, and the organic material it has preserved for tens of thousands of years is now entering the environment as dissolved organic matter in streams and rivers. Bacteria are converting the organic material into carbon dioxide, which is being released into the atmosphere.

A bank of permafrost thaws near the Kolyma River in Siberia

A bank of permafrost thaws near the Kolyma River in Siberia

The current paper examines the effect of sunlight on the dissolved carbon compounds. The researchers discovered that sunlight changes the chemistry of the permafrost carbon, however sunlight alone does not convert the permafrost carbon to carbon dioxide. The researchers concluded the decomposition of organic materials via bacteria is mostly likely the key process for converting permafrost carbon within rivers into carbon dioxide.

The research team includes co-lead author Robert Spencer of Florida State University; co-authors Leanne Powers and Thais Bittar from UGA Skidaway Institute; Paul Mann from Northumbria University; Thorsten Dittmar from Carl von Ossietzky University of Oldenburg; Cameron McIntyre from the Scottish Universities Environmental Research Centre; Timothy Eglinton from ETH Zurich; and Nikita Zimov from the Russian Academy of Science.  While climatologists are carefully watching carbon dioxide levels in the atmosphere, another group of scientists is exploring a massive storehouse of carbon that has the potential to significantly affect the climate change picture.