Skidaway scientists attend ASLO

Skidaway Institute was well represented at the 2017 Association for the Sciences of Limnology and Oceanography Aquatic Sciences Meeting in Honolulu, Hawaii,  February 26 – March 3.

Aron Stubbins and Sasha Wagner chaired a two-day session titled “The Biogeochemistry of Dissolved Organic Matter.”

Sasha presented her research on “Stable Carbon Isotopes Offer New Insight into the Biogeochemical Cycling of Black Carbon.” Aron, Jay Brandes and A. Ramapo Goranov, from the College of New Jersey were co-authors.

Former Skidaway Institute intern (Stubbins Lab) Camisha Few presented a poster “Photodegradation of Dissolved Organic Carbon Within the Connecticut River Watershed.” Camisha is a student at Florida A&M University. Her co-authors included Aron, Sasha, Kevin Ryan and K. Haiat-Sasson from the University of Rhode Island.

Camisha Few explaining all about CDOM and FDOM photochemistry at S+ASLO 2017

Aron presented his work on “Tree-Dom: DOM from the Crowning Headwaters of the Aquatic Carbon Cycle.” His co-authors included Sasha, T. Dittmar from the University of Oldenburg, Germany, and J.T. Van Stan from Georgia Southern University.

Thais Bittar presented “Growth, Grazing and Virus-Induced Mortality of Bacterioplankton in the Sargasso Sea.” Her co-authors included Karrie Bulski, Elizabeth Harvey, R. Parsons from the Bermuda Institute of Ocean Sciences, S. Giovannoni from Oregon State University and C. Carlson from UC-Santa Barbara.

Cliff Buck and Chris Marsay also made presentations. Cliff chaired a session on atmospheric deposition, “Linking atmospheric deposition to the biogeochemistry of aquatic and marine systems.” His co-organizer was Rachel Shelley from LEMAR-Universite de Bretagne Occidentale, France.

Both Cliff and Chris gave talks about data from the Arctic cruise in a session titled “Biogeochemical Cycling Trace Elements and Isotopes in the Arctic Ocean.”  Cliff’s talk was on the aerosol data and titled “Aerosol Concentration, Composition and Fractional Solubility on the US Geotraces Western Arctic Cruise.” In addition to Chris, his co-authors included A. Ebling, P. Morton, B Summers and W. Landing, all from Florida State University. Chris presented melt pond data, “Dissolved and Particulate Trace Elements in Arctic Melt Ponds.” In addition to Cliff, his co-authors included P. Morton, B Summers and W. Landing, all from Florida State University, and S. Rauschenberg and B.S. Twining, both from the Bigelow Laboratory for Ocean Sciences.

 

UGA Skidaway Institute research paper selected for Research Spotlight

A research paper by SkIO’s 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.

Aron’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.

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.

UGA Skidaway Institute scientist authors paper on coral superoxide production

University of Georgia Skidaway Institute of Oceanography researcher Julia Diaz recently co-authored a paper published in the journal Frontiers in Marine Science. The paper, titled Dark Production of Extracellular Superoxide by the Coral Porites astreoides and Representative Symbionts, appeared in the journal’s November 24^th issue.

The lead authors were Tong Zhang from Nankai University, as well as Diaz. Additional co-authors included Caterina Brighi from the Imperial College London in London, U.K.; Rachel Parsons from the Bermuda Institute of Ocean Sciences; Sean McNally from the University of Massachusetts; and Amy Apprill and Colleen Hansel, both from the Woods Hole Oceanographic Institution.

The paper examines the production of superoxide by the Porites astreoides species of coral. Superoxide is an oxygen (O₂) molecule with an extra electron, giving it a negative charge. Scientists believe it may have both beneficial and harmful effects on the coral, ranging from helping it resist disease to damage through coral bleaching. The research team determined the Porites astreoides coral produces superoxide, but that production is not related to photosynthetic activity or the presence of light. This led the team to question whether the superoxide production may play a beneficial role in coral physiology.

The paper can be accessed here: http://journal.frontiersin.org/article/10.3389/fmars.2016.00232/full

UGA Skidaway Institute associate professor cited for top research articles

Aron Stubbins is one of just a handful of researchers cited in the journal Limnology and Oceanography for authoring two of the journal’s top scientific papers over the past 60 years.

Limnology and Oceanography is an official publication of the Association for the Sciences of Limnology and Oceanography and is considered a premier scientific journal. In its recently published 60th anniversary issue, the journal collected and republished the 10 most cited research papers for each of the last six decades. Aron authored or co-authored two of those papers, one in 2008 and the other in 2010.

“It came as quite a surprise to see two articles show up on the list,” Aron said. “I was at a conference and wasn’t really checking my email when one of my colleagues let me know.”

The journal used the number of times a paper was cited in future studies as the yardstick to determine which papers should be included on the list. It is one commonly used method for measuring the impact of a scientist’s work.

“The list isn’t really about popularity,” he said. “It’s about usefulness. That people have found some of my work useful over the years is rewarding.”

The 2008 paper was titled “Absorption spectral slopes and slope ratios as indicators of molecular weight, source, and photobleaching of chromophoric dissolved organic matter.” The lead author was John Helms. Aron was a co-author along with four other scientists. The research team developed a new method for extracting new information from a relatively common and simple test of the color of dissolved organic matter.

Aron was the lead author, along with nine co-authors, of the second paper, “Illuminated darkness: Molecular signatures of Congo River dissolved organic matter and its photochemical alteration as revealed by ultrahigh precision mass spectrometry.” The study examined organic carbon carried to the ocean by the Congo River — after the Amazon, the second largest river in the world in terms of carbon and water flow. The research team studied how sunlight degrades organic material, including which compounds are degraded, which are not and what new compounds are created when sunlight shines on river water.

“His inclusion in this seminal volume is quite an honor for Dr. Stubbins,” UGA Skidaway Institute Interim Director Clark Alexander said. “This recognition validates what we have always known, that he is conducting groundbreaking and meaningful research that is recognized around the world.”

All 60 papers can be found at http://aslopubs.onlinelibrary.wiley.com/.