Kansas City (Mo.) Star
December 11, 2005


By Glennda Chui, Knight Ridder Newspapers

SAN JOSE, Calif. -- Suburbia may be familiar turf, but it's one of the
last frontiers for scientists trying to understand how ecosystems work
and how people are changing the natural world.

From the woodsy suburban enclaves of Vermont to sprawling Chico,
Livermore and Gilroy [in California], researchers are starting to
probe the role of lawns in global warming, how garden fertilizers and
pesticides affect wildlife and how storm water running from roofs,
roads and driveways undermines the health of streams.

"The suburban landscape is large, and it's growing," said Jennifer
Jenkins of the University of Vermont, one of the scientists who
reported her findings last week at a meeting of the American
Geophysical Union in San Francisco. "There's this enormous land
surface that's falling through the cracks."

Jenkins is involved in a study of 40 suburban yards near Baltimore.
Researchers will clip plots of lawn by hand, weigh the clippings,
measure the grass stubble and thatch and even rake up leaves for

The goal is to see how much carbon dioxide the lawns absorb and give
off, and whether they're contributing to global warming or slowing it

Others are trying to figure out how to design suburban neighborhoods
that do less damage to their surroundings.

"We're trying to think about ways to use ecological engineering, green
engineering approaches, to solve the problem at its source," said
Breck Bowden, also of the University of Vermont.

From a scientific standpoint, it's hard to even define what suburbia
is. It slowly grades from sprawling tract housing on the fringes of
cities to homes on half-acre lots to the "exurbs" or "ruburbs" -
scattered homes on mostly rural land.

Ecologists have cut their teeth on studies of forests and bogs,
deserts and tundra and rain forest, but only recently did they turn to
suburbia. Maybe that's because people-dominated landscapes are so
complicated and always changing, Jenkins said; maybe they're just less
exotic places to work.

But the 'burbs have a big impact. For instance, of all the carbon
stored in trees in Maryland, only about two-thirds is in forests; the
rest is in trees planted in yards and median strips, Jenkins found in
an earlier study.

That impact is bound to grow. Suburbs are among the fastest-growing
land covers in the United States and in the world, said Daniel Bain of
the U.S. Geological Survey in Menlo Park, Calif., one of the
organizers of last week's sessions.

One of the first things that happens when people develop farm fields
or wild lands is that they pave over parts of it. A study last year
found that more than 43,000 square miles of the United States is paved
or built upon, an area roughly the size of Ohio.

As a result, rainwater that once would have trickled through the soil
gets into streams a lot faster, Bain said. The rushing water scours
the banks, cutting the streams deeper and sweeping away habitats for
plants, animals and bugs.

It doesn't take much surrounding pavement to severely damage a stream,
Bowden said. Even if 15 percent or 20 percent is paved -- typical for
a medium-density suburb -- "you have severe degradation," he said.
"We're essentially pounding them to death with excess water."

For wildlife, the suburbs are a mixed blessing.

Some animals manage to thrive and even become pests: Garden-wrecking
deer. Garbage-raiding raccoons. Squawking crows and blue jays.
Coyotes, black bears and mountain lions drop by some California
neighborhoods, stealing food and scaring residents.

Yet many others are driven away or wiped out. On balance, suburbia's
rapid spread is probably the biggest threat to the diversity of
wildlife in the developed world, according to a 2003 review by Stephen
DeStefano of the U.S. Geological Survey and Richard DeGraaf of the
U.S. Forest Service.

Fertilizers are also a problem, running off lawns and gardens into
streams and eventually into the sea.

While it might seem like a good thing to give wild plants a dose of
fertilizer, the results are often disastrous, said Lawrence Band of
the University of North Carolina. The nitrogen in fertilizer triggers
algae blooms in the ocean. When the algae die, sink to the bottom and
rot, they use up the oxygen in the water, resulting in "dead zones"
that kill fish and other wildlife.

Studies from Santa Barbara to Maryland's Chesapeake Bay are trying to
track down the sources of nitrogen contamination and find ways to slow
it. The cost of restoring Chesapeake Bay alone is estimated at $18
billion, Band said.

Ultimately, scientists hope their findings will filter into designs
for better neighborhoods. They might include paving materials that let
some of the water seep into the ground, rain barrels that catch the
runoff from gutters, or even sod roofs like the one being installed at
the new California Academy of Sciences in San Francisco.

"We have to be patient," Bowden said. "It's taken us 100 years to get
into this state of having messed things up. It's going to take us a
little time to recover."

Copyright 2005 KRT Wire