Editor’s note: Sadie Gorman and Monica Tse will present their Alaskan research this afternoon at the Homecoming Summer Research Poster Session. They are two of 17 students presenting.
This summer, a group of Union College environmental scientists, with backgrounds in chemistry and geology, traveled to the Kenai Peninsula in south central Alaska to collect samples and document the impact of environmental change in several large watersheds on the peninsula.
“Watersheds and their surrounding environments are intricate systems that require a multi-disciplinary approach to understand the physical and chemical characteristics of their components,” says Assistant Professor of Chemistry Laura MacManus-Spencer.
“Working in remote, cold regions such as the Kenai Peninsula is important,” says Visiting Instructor of Geology Jaclyn Cockburn. “These areas are relatively pristine and thought to be more sensitive to environmental changes, such as climate variability and the influence of contaminants, than some temperate regions such as upstate New York.”
Cockburn and Sam Basta ’08, an Environmental Studies major, and Kara Gillivan ’08, a Geology major, headed to the Kenai Peninsula in early July to collect sediment samples and perform simple water column measurements from glacially fed Skilak Lake through the major glacial melt period of the hydrological season.
Both students are using their sediment and summer observations as part of their senior thesis projects.
Basta’s research is concerned with characterizing and mapping the accumulation rates in the proximal basin of Skilak Lake. Through investigations of the recent sedimentary record, he hopes to identify zones of higher accumulation that will be targeted for further sampling in future years.
“In sedimentary records with visible, annual accumulation layers, called varves, the thickness of each layer can be related to hydroclimatological conditions,” says Basta. “This can be used to reconstruct hydroclimate conditions beyond the instrument weather records.”
Gillivan will investigate the role recent climate change has played on the dynamics of the Harding Icefield and several smaller glaciers that flow from it, such as Skilak Glacier. Increased glacial runoff may lead to increased sediment loads in streams on the Kenai Peninsula, which may have serious impacts on aquatic ecosystems.
“Being in Alaska this summer gave me an opportunity to see first hand what has happened recently to the smaller glaciers and the watersheds they feed,” said Gillivan.
After a week, the trio was joined by MacManus-Spencer, Chemistry major Monica Tse ’08 and Biochemistry major Sadie Gorman ’08.
Tse and Gorman explored the lakes and rivers of the local watershed, collecting sediment and surface water samples. Tse will use the water samples for her senior thesis, in which she studies the photodegradation of UV filter chemicals, such as those found in sunblock, in natural waters.
“The photochemical behavior of UV filter chemicals spiked into the Alaskan water samples offers a point of comparison to experiments conducted with chemically different water samples collected in New York’s Capital Region,” says Tse.
Gorman will use the sediment samples in her senior thesis research to study the potential for UV filter chemicals to bioaccumulate in sediment-dwelling organisms. She will spike the sediment with the chemicals and then measure their uptake in worms added to the samples.
“This type of experiment helps us to understand whether or not these chemicals, once in the environment, will accumulate up the food chain,” says Gorman.
During the trip, MacManus-Spencer, Tse and Gorman also partnered with staff from the Kenai Watershed Forum, a nonprofit organization in Soldotna, Alaska, that monitors and protects Kenai River water quality. Forum staff took the students on their sampling boat to collect water and sediment samples. In return, the students helped with their routine water sampling.
“The research efforts from both our groups will overlap in the physical and chemical characterization of the water and sediment samples collected,” says MacManus-Spencer. “Each group will learn from the other about the relevant geological and chemical characteristics of the samples.”
The Alaskan research spanned three weeks. Each of the four Union students received a summer research grant through the College’s Internal Education Foundation (IEF). In addition, Basta received a Surdna Summer Research Fellowship; Gillivan received a half-summer fellowship; and Gorman and Tse were awarded fellowships through the Lee Davenport ’37 Summer Research Fund.
Additional funding for the trip came from Union’s Geology Field Fund, the Geology Department and the Union Faculty Research Fund.