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Great Lakes
Article:
OSU looking at how people affect Lake
Erie
By Mike Lafferty
The Columbus Dispatch
Published December 16th, 2004
COLUMBUS, Ohio -- In August 1679, French explorers boarded
a small, two-masted ship christened the Griffin and sailed
off into what would later be named Lake Erie.
The vessel, the first to carry Europeans the length of
the lake, continued north into waters later dubbed Huron
and Michigan.
Although the ship disappeared without a trace, the voyage
opened the upper Great Lakes to trade and eventually settlements.
In the three centuries since the Griffin's voyage, Lake
Erie has become a swimming pool, a fishing hole and a
boating basin. It's a highway for cargo ships carrying
the world's flags, a supply of drinking water for 11 million
people and an industrial dumping ground.
With the smallest water volume of the five Great Lakes,
Erie also is the most vulnerable.
Scientists have studied the lake for decades, but their
research has been focused on specific areas. Some looked
at algae blooms, pollution or fishing; others examined
non-native species.
Now, armed with a four-year, $1.4 million federal grant,
Ohio State University researchers will examine the whole
enchilada _ how we affect the lake and how it affects
us.
OSU biologist David Culver and 15 colleagues at Ohio
State and other universities will create mathematical
models based on physics, biology, chemistry, economics
and other research disciplines.
"We want to get at the right questions about the
interactions between humans and natural systems,"
he said.
Starting with a simple, one-dimensional model, the researchers
plan to add increasingly complex data to describe Erie's
behavior. The goal is to produce a model that can be applied
to any large lake in the world.
"There are lots of lakes like this. Wherever there's
a big lake, people go there," Culver said.
The scientists plan to look at how the lake affects people
by examining issues such as drinking water and the quality
of life of the residents along its shores.
How people affect the lake, however, is more dramatic.
"We're loving it to death," Culver said. "What
happens when you double erosion flowing into the lake
or a new chemical enters the mix? How do lake organisms
react to foreign species?
"What if boating or swimming use is doubled? Should
you build a nuclear power plant or a coal-fired plant?"
Something as simple as building a road in a subdivision
has an impact. The more asphalt and concrete, the faster
rainfall runs off into rivers that drain into the lake.
More water in streams also increases erosion and the amount
of contaminated sediments that flow into the lake.
And even our own daily activities can affect the lake,
said Tim Loftus, director of the Water Quality Laboratory
at Heidelberg College in Seneca County.
"In Ohio, you can be 100 miles away in Shelby County
and do something on your land that will have an impact
on Lake Erie," he said.
The lake pays a price when homeowners overapply lawn
chemicals, spill gasoline or dump paint or household chemicals.
Industrial, home and farm pollution cause beach closings,
and fishing and drinking water advisories. Retired commercial
fisherman Lee Stinson started fishing in 1960 and continues
to keep a hand in the business his son now runs.
"The lake is changing all the time," Stinson
said. "They stopped phosphorous (from sewage treatment
plants). It used to be you'd see suds knee-deep all along
the way down the beach."
Controlling phosphorus and other chemicals from farms,
however, is far more difficult.
Culver said something as innocuous as a sale on farm
fertilizer can have an effect. A few years ago, he said,
fertilizer manufacturers began offering winter discounts.
Farmers responded by buying fertilizer early and spreading
it on fields.
"This phosphorus fertilizer was sitting on top of
the soil and spring rains come and there could be a lot
of runoff," he said.
By the 1930s, pollution had wiped out whitefish and lake
herring in Erie.
Two decades later, sewage and farm and industrial chemicals
killed off the lake's mayfly population, which emerged
each spring and provided food for fish and birds.
Since the 1970s, there have been steady declines in many
toxic and persistent chemicals in the Great Lakes. That,
in turn, has meant lower levels of contaminants, including
lead, found in humans.
Overall, pollution has wreaked havoc with birds, including
gulls and cormorants. Reproduction drastically declined
as researchers determined DDT was causing birds to lay
eggs with thin shells that broke too easily. DDT and other
chemicals were banned by the 1980s, but problems persist.
"(Birds) are still being impacted by these pollutants,"
said Keith Grasman, a Wright State University environmental
toxicologist.
While PCBs and other hazardous chemicals are banned or
severely restricted, newly invented classes of chemicals
are showing up in the food chain. Canadian environmental
and health authorities are noting problems with snapping
turtles, mink birds and other wildlife.
Grasman is testing wildlife in western Lake Erie, the
Detroit River and Lake Ontario as part of a Canadian study.
"We see wildlife health problems in most of these
locations _ immune suppression in birds, evidence of thyroid
problems," he said.
"There are a number of industrial chemicals that
have got out there. Our society uses 60,000 to 80,0000
chemicals with 1,000 new ones a year."
While some chemical pollution can be controlled, there's
little that can be done about invasive species that have
entered the lake. Every foreign cargo ship that enters
the waterway is a threat.
More than 180 foreign species of plants and animals,
including zebra mussels, gobies, river ruffe and white
perch, now live in the lake and along its shores.
"We're the vectors for moving these guys around,"
said Henry Vanderploeg, a scientist at the Great Lakes
Environmental Research Lab in Ann Arbor, Mich.
"What are they doing to the lakes? The answer is,
we don't know, and we keep introducing them."
A new species often proliferates because it has no natural
enemies. This alters the biological mix in the lake, which
has a fixed amount of energy that must be divided among
all the species present.
Nothing demonstrates biological complexity like the zebra
and quagga mussels. These thumb-size freshwater clams
native to central Asia arrived in the Great Lakes in a
cargo ship's water ballast in the 1980s.
They're still reworking Erie's ecosystem. Because the
mussels have filtered algae from the water and boosted
water clarity, more sunlight penetrates the lake and more
vegetation grows in shallow areas along the shore. This,
in turn, has, benefited smallmouth bass.
"They're just booming now," Stinson said.
But the mussels also colonize along hard surfaces _ as
many as 200,000 per square yard _ and can drastically
reduce the flow through water intake and outflow pipes
of Great Lakes industries.
Keeping the pipes clean is expected to cost the industries
billions of dollars, according to the U.S. Fish and Wildlife
Service.
Zebras and quaggas also have been linked to the return
of toxic blue-green algae, known as microcystis. Because
they don't like the taste of microcystis, the mussels
spit it out, while eating other blue-green algae.
One goal of an overall model is to predict how the mussels
may continue to alter the lake.
Eventually, a more complex model would consider a multitude
of land use, industrial and agricultural activities in
any part of the lake and at any depth.
A model must also consider changes that might occur far
from the lake _ perhaps thousands of miles away.
The mix of the chemicals entering Lake Erie changed remarkably
after the 1970s. Part of the reason was that Japan and
other foreign steel producers started to drive domestic
iron and steel makers out of the market.
"If there were a lot of steel mills in Cleveland
today, we'd be doing an entirely different study,"
Culver said. "The lake has changed because of something
that happened in Japan."
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