Thanks to a $100,000 grant from the National Science Foundation, two 91ֿ professors are researching climate change in Alaska. Elizabeth Herndon, Ph.D., and Lauren Kinsman-Costello, Ph.D., assistant professors from 91ֿ's College of Arts and Sciences, spent a week in Fairbanks, Alaska in June studying how climate change affects the availability of plant nutrients in arctic and sub-arctic ecosystems.
The grant teams up two of 91ֿ’s newest researchers.
“I think it’s really great that two early-career scientists were awarded the funds to do this research,” Herndon said.
Both Herndon and Kinsman-Costello joined 91ֿ about two years ago, and their new collaborative research effort has potential implications for understanding how high-latitude peatlands will respond to climate change.
“It’s this very cold, wet environment, but temperatures at high-latitudes are actually increasing at twice the rate they’re rising anywhere else on the planet,” Herndon said. “It’s thawing the permafrost, and driving shifts in vegetation and in hydrology. A lot of people are interested in how these environments will respond to the warming climate because they currently store a lot of carbon that has the potential to be released into the atmosphere and accelerate climate change.”
Herndon said that as the temperatures rise in the arctic, plants will grow bigger and forests will expand further north. Shrubs and other woody plants are already replacing tundra vegetation across large areas of northern Alaska, Canada, and other arctic countries.
“What we want to know is how these factors will change the availability of nutrients, specifically phosphate, that help plants grow,” Herndon said. “Rising temperatures are drying out existing wetlands, and this is causing iron that’s dissolved in the soil water to essentially rust out as iron oxide minerals in the soil.”
Phosphate, Herndon said, binds to iron oxides. That means that increased iron deposits could sequester phosphate, reducing the amount available to plants.
“Those plants are a sink for carbon dioxide,” she said, “so any nutrient limitation could also limit their ability to remove CO2 from the air."
Soils in high-latitude regions like Alaska contain high amounts of carbon because the vegetation decomposes slowly due to cold temperatures, leaving large amounts of peat.
“As the temperatures rise, that peat is going to start decomposing more quickly and releasing more carbon dioxide,” Herndon said.
While the available data leave some uncertainty for future changes in the arctic, Herndon said the conventional wisdom suggests a bleak picture.
“If the plants there aren’t growing enough, then they can’t absorb the excess CO2 released from peat decomposition,” she said. “Right now, it’s not clear what the difference will be, but the prediction is that the carbon dioxide released will be greater than what the plants can absorb from the atmosphere.”
The team, which also includes one graduate and one undergraduate student, spent a week at the Alaska Peatland Experiment (APEX) Site, just outside Fairbanks, where a team of scientists have been using an adjusted water table in a wetland to study carbon dioxide and methane release.
The scientists flooded one-third of the wetland, while draining another one-third. The differential creates the perfect model for Herndon and Kinsman-Costello’s research into phosphate and iron.
Herndon brings her iron expertise while Kinsman-Costello is versed in phosphates.
“We’re combining our knowledge bases to understand the interactions between the two,” Herndon said. “Lauren is a great collaborator so I’m really happy to be working on this project with her.”
Herndon said she hopes that this pilot project will yield data that can be used to develop a longer-term project, as well as integrate with what the other scientists in Fairbanks are studying.
Photo Caption:
(Left to right) Jonathan Mills, undergraduate geology major; Kiersten Duroe, geology MS Candidate; Elizabeth Herndon, Ph.D., assistant professor of geology; Lauren Kinsman-Costello, Ph.D., assistant professor of biology in 91ֿ's College of the Arts and Sciences.
READ MORE ABOUT BETH AND LAUREN