As concern over global warming escalates, researchers are turning to an unsuspecting vegetation matter that may provide a crucial link to sea-level rise. Peat bogs, a type of wetland where an organic matter called peat forms, act much like a natural sponge. At nearly 95 percent water, the peat bogs are expanding, allowing greater absorption of water.
Researchers in Lehigh’s earth and environmental sciences department
are studying peat bogs in Alaska to determine if this type of ecosystem could potentially offset sea-level rise from glacial melt. Zicheng Yu
, associate professor, and an interdisciplinary team of environmental scientists have been working in Alaska, where climate has warmed at a faster rate—about double the global rate of warming. As a result, melting mountain glaciers in Alaska and in the Arctic are prompting concern over sea-level rise.
The team believes that glacial melting is modifying the area’s climate, particularly the air humidity during growing season, which is helping promote the growth of peatlands.
“These peat bog ecosystems in the Northern Hemisphere contain one-third global soil carbon with less than 3 percent land mass area,” Yu says. “So the expansion or shrinkage of these carbon-rich ecosystems has important influence on the global carbon cycle, feeding back to global climate change. If these peat bogs absorb more water, in addition to carbon, it would have implication on global sea-level rise.”
Tracking changes over time
Yu is working with Lehigh assistant professors Bob Booth
and Joan Ramage
, PhD candidate Julie Loisel and post-doctoral fellow Miriam Jones, as well as Bryan Mark from Ohio State University.
Their work is funded by the National Science Foundation’s
Emerging Topics in Biogeochemical Cycles Program for three years. According to Yu, the project will also examine modern ecological and hydrological dynamics of these peat bogs and recent change using remote sensing images.
Another part of the research, conducted by Loisel, focuses on paleoecology and carbon cycle in Alaskan peat bogs. By studying past climate change, she can determine how different time scales impact this ecosystem—from yearly changes to change over a couple thousand years.
“I’m looking at how peat accumulates over time,” says Loisel, who began studying climate change and peat bog dynamics as a graduate student in Quebec. “Alaska is important because those ecosystems experience fast changes and extremes in temperature. I’m interested in how this affects the growth of peatlands and how that compares to other areas.”
Loisel, who came to Lehigh under a fellowship from the Natural Sciences and Engineering Research Council of Canada
, is looking forward to beginning a new project for her dissertation research that will take her to Patagonia in January. Working in southern South America will give Loisel the opportunity to compare responses and controls of peat bogs in the Northern and Southern Hemispheres.
“Patagonia is completely opposite in geographic position from Alaska,” Loisel says. “I can ask different questions specific to the region and show if there are opposite trends.”
Posted on Monday, August 24, 2009