Student Focus
Trees tell the history of one of New
England's largest old-growth forests
In order to read a tree's life story,
Shawn Fraver extracts a pencil-thin core from the trunk, then sands the
wood to a fine sheen to expose the growth rings. Each ring reveals a
year in which the tree took advantage of ideal conditions to grow
rapidly, or in which the tree grew very little, saving its resources to
survive drought or insect attack.
Fraver, a University of Maine Ph.D. student from Old Town, Maine, is
studying tree growth in the Big Reed Forest Reserve in northern
Piscataquis County. Owned by The Nature Conservancy, Big Reed
constitutes one of the largest tracts of old-growth forest in New
England.
With support from a nationally competitive U.S. Environmental Protection
Agency STAR fellowship, Fraver is delving into the cycles of growth and
disturbance at Big Reed. The goal is to describe how the forest responds
to environmental changes year to year.
In the UMaine Department of Forest Ecosystem Science, Fraver is working
with Associate Professor Alan White, who coordinates the research
project at Big Reed.
The results will yield benefits to forest managers who increasingly look
for guidance in natural patterns of forest growth, Fraver says.
Understanding the scale and frequency of natural disturbances also will
contribute to future decisions about forest reserves.
Fraver has found that most of the older trees at Big Reed are around 200
years old, although he also has found quite a few that exceed 300 years.
"It seems apparent that there was a catastrophic disturbance — perhaps a
hurricane — that wiped out many of the trees in the late 1700s and
allowed a large new group of trees to become established," he says.
Changing Ice Sheets
Working for NASA on the West Antarctic Ice Sheet
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Vandy Spikes
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Over the next few years, scientists
will be working hard to determine conclusively if the world's ice sheets
and glaciers are shrinking, growing or remaining unchanged. Their
results will have significant implications for the debate over global
climate change.
At the heart of that discussion will be research by Vandy Spikes, a
University of Maine Ph.D. student in geological sciences.
Spikes will use a fellowship from the National Aeronautics and Space
Administration (NASA) to establish precise elevations for points on the
West Antarctic Ice Sheet. His results will help to interpret data from a
new ice monitoring satellite launched by NASA.
Spikes is working with Gordon Hamilton, a research assistant professor
in UMaine's Institute for Quaternary and Climate Studies, and Steven
Arcone of the Cold Regions Research and Engineering Laboratory in
Hanover, N.H.
"The Antarctic ice sheet is changing, and while it is getting thicker in
some places, most evidence suggests it is generally getting thinner,"
Spikes says. However, the evidence collected so far comes from elevation
measurements at widely scattered points on the ice, he adds. The picture
that has emerged is rough.
When data start coming from ICESat, a NASA satellite launched in
December, the picture will come into better focus. The raw data must be
adjusted to account for a variety of factors, such as the temperature
and humidity of the atmosphere, and the position of the satellite.
Spikes will work with NASA to perform those calculations.
Battlefield Sensors
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Wendy Kresge
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The learning environment for University
of Maine physics undergraduate Wendy Kresge goes far beyond the
classroom. For the past two years, she has worked at UMaine's Laboratory
for Surface Science and Technology (LASST), which is nationally
recognized for its research on products that are vital to the government
and the industrial sector.
Kresge is helping to develop chemiresistive sensors to detect the
presence of chemical and biological agents on the battlefield.
The senior from Gilbert, Pa., says she feels privileged to be
contributing to the development of a technology that may one day save
lives. But she knows that she wouldn't have had that opportunity without
the unique learning experience that has been available to her at LASST.
"It's a fantastic working environment. LASST provides a teaching
environment, so it's more than just a professional lab that develops
products. It has allowed me to connect the theory I learn in class to
hands-on experience," Kresge says.
Kresge fabricates sensors by using one of two processes to grow a thin
film on a surface: sputtering or electron beam evaporation. These
processes take place in an ultra-high vacuum and involve knocking off or
evaporating individual atoms from a high purity metal source and
depositing them onto the surface of a sapphire crystal to produce a
pattern.
Kresge says she plans to build on the knowledge and experience she has
gained at UMaine by pursuing a master's degree in physics. (Kresge also
is pictured on the cover of this issue.)
Guarding the Welfare of Water
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Catherine Schmitt
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We expect the water coming out of our
faucets to be clean and healthful. To help Maine water suppliers keep it
that way, the Senator George J. Mitchell Center for Environmental and
Watershed Research at The University of Maine is working to address new
federal regulations that could be a burden, especially for small, rural
water systems.
Spearheading the work are Catherine Schmitt, a master's degree student
in the Ecology and Environmental Sciences Program, and John Peckenham,
interim director at the Mitchell Center. Nine Maine water utilities, the
Maine Water Utilities Association and the Maine Drinking Water Program
also are participating in the project, which focuses on protecting
ponds, streams and other surface water sources.
Consulting on environmental matters is nothing new for Schmitt, a native
of Glen Rock, N.J. Before coming to UMaine, she worked in Massachusetts
on issues related to development around wetlands.
In her academic program, she is researching issues related to the use of
chlorine to disinfect drinking water. By disinfecting water with
chlorine, water suppliers create unwanted by-products harmful to health.
Schmitt's research will address the possibility that, in some
circumstances, drought conditions may lead to an increase in the harmful
compounds generated by disinfection.
Schmitt and Peckenham plan to produce a report on watershed protection
for water suppliers in 2002.
