Student Focus
Enriching experiments
Surrounded by wetlands and wooded
hills, a scenic estuary near Bar Harbor, Maine, seems like one of the
last places to study water pollution. But University of Maine graduate
student Rachel Keats has been using Northeast Creek estuary on the
northeast side of Mt. Desert Island to study changes in aquatic food
webs when nutrient levels rise as a result of runoff.
Keats worked in a cooperative project with Laurie Osher, assistant
professor in the Department of Plant, Soil and Environmental Sciences,
and Hilary Neckles at the U.S. Geological Survey (USGS). The integrated
ecosystem project led by USGS is one of the few in Maine's coastal
waters exploring the potential for such changes.
"The goal was to find out at what level of nitrogen in the water there
was a response in the ecosystem," says Keats of her experiments that
began in 2001. The Niskayuna, N.Y., native received her master's degree
in ecology last year, and will begin graduate work this fall in the
UMaine Department of Spatial Information Science and Engineering.
In her research, Keats collected samples of invertebrates, sediment and
plant materials from experimental enclosures established and maintained
by USGS, as well as from unenclosed control locations. Each enclosure,
about the size of a washing machine, had clear plastic sides and an open
top and bottom. Nitrogen fertilizer was added to the enclosures at three
different constant rates to simulate nutrient enrichment at three
different levels. To provide a control, researchers did not add nitrogen
to some of the enclosures.
Keats estimated the numbers and types of invertebrates, and sent
materials to a laboratory for stable isotope analysis. Some stable
isotopes can indicate changes in ecological processes.
"At the highest levels of loading, there was a shift in the insect
community," says Keats. "There was an increase in the number of worms.
Damselfly larvae and midges that graze on algae were pretty much wiped
out. Generally, the community shifted from a diverse group of insects
that graze and specialize in what they eat to a deposit-feeding
community — insects that will eat anything."
The changes were most significant at levels of nutrient enrichment that
are higher than what is typically seen in developing watersheds, Keats
adds. In that sense, they represent an extreme scenario of actual
ecosystem change in response to development.
Keats also documented similar but less severe changes at lower levels of
enrichment.
Securing the future
Gene Connolly, a University of Maine senior in computer science from
South Berwick, Maine, never thought he'd worry about — let alone work on
— issues related to homeland security.
"The subject never crossed my mind while I was growing up. If anyone had
asked, I guess I would have thought that it was something that people in
other countries worried about," he says.
For his honors research project, Connolly is working with UMaine
Fulbright Visiting Professor Anatoly Sachenko, director of the Institute
of Computer Information Technologies at the Ternopil Academy of National
Economy in the Ukraine. They are exploring ways to link Internet
addresses with geographic locations and to analyze electronic
information for its potential relevance to terrorism.
In addition to Sachenko, Connolly's advisors include computer science
professors George Markowsky and Tom Wheeler.
Connolly came to UMaine for academic and financial reasons — and the
UMaine swim team. He was the first student at Marshwood High School to
win a state swimming medal (500-yard freestyle). At UMaine, Connolly has
competed for four years and is team captain.
Complementing his university experience, Connolly worked two summers for
EigenSoft Inc., a business software developer located in Portsmouth, N.H.
