(No subject)

[Guest guest]

well there ya go...

go plant some trees

all the best

Craig

 

 

 

 

 

Dear EarthTalk: Do urban trees really help reduce pollution and clean the air?

 

— John Alderman, Washington, D.C.

 

Back in 1872 Frederick Law Olmsted, the granddaddy of American landscape

architecture and the designer of New York's Central Park, proclaimed that trees

were the " lungs of the city. "

 

While Olmsted's statement may have been more philosophical than scientific,

researchers have since found that city trees do indeed perform important

environmental functions like soaking up ground-level pollutants and storing

carbon dioxide, which helps offset global warming.

 

Each year in Chicago, for example, the windy city's urban tree canopy removes 15

metric tons of carbon monoxide, 84 metric tons of sulfur dioxide, 89 metric tons

of nitrogen dioxide, 191 metric tons of ozone and 212 metric tons of

particulates, according to David Nowak, project leader of the U.S. Forest

Service's Urban Forest Ecosystem Research Unit.

 

Trees absorb these gaseous pollutants via the tiny pores in their leaves and

break them down into less harmful molecules during photosynthesis.

 

In Sacramento, California, a public-private partnership called Sacramento Shade

spearheaded the planting of more than 200,000 trees around the city in the

mid-1990s. In a study assessing Sacramento's bolstered tree cover, Greg

McPherson of the Western Center for Urban Forest Research found that the

region's urban forest removes more than 200,000 metric tons of carbon dioxide

from the atmosphere each year, saving taxpayers as much as $3 million annually

in pollution cleanup costs.

 

Meanwhile, the tree cover in New York City helps remove enough airborne toxins

to save taxpayers as much as $10 million a year in pollution mitigation costs,

according to Nowak. The Big Apple's five boroughs are home to more than 5

million trees, covering nearly 17 percent of its public and private land, he

added.

 

Gary Moll, a vice president at the nonprofit group American Forests, asserts

that trees are the " ultimate urban multi-taskers, " absorbing carbon dioxide and

acting as filters, sponges, humidifiers, heat shields, and wind blockers. Under

Moll's supervision, American Forests is assessing the costs and benefits of city

tree cover across the country. The group uses a combination of satellite data,

field surveys, and computer modeling technology to measure regional tree canopy

and calculate its dollar value.

 

All told, Olmsted was right in his assessment of the importance of city trees.

Indeed, planting trees in urban environments may be one of the best medicines

available to help restore our ailing cities.

 

 

Dear EarthTalk: What are ìwildlife corridors? And how do they help preserve

wildlife and biodiversity?

 

— J. J. Harris, Hilo, Hawaii

 

Wildlife corridors are stretches of land that connect otherwise fragmented

pieces of wildlife habitat. Since many mammals and birds require large ranges of

undeveloped land in order to survive, linking smaller habitats together is key

to maintaining strong populations. Ecologists consider wildlife corridors

crucial because they increase the total amount of habitat available for species,

while counteracting the fragmentation that has resulted from human activity.

 

First espoused by Harvard biologist Edward O. Wilson in the 1960s and later by

environmentalists considered on the fringe, the wildlife corridor concept has

since become an institutionalized technique for managing at-risk wildlife

populations.

 

The benefits — including greater biodiversity, larger wildlife populations,

wider ranges of food sources and shelter, and increased long-term genetic

viability due to population interbreeding — are now well known and undisputed by

wildlife professionals. Corridor projects have sprung up from coast to coast, in

some cases implemented by the U.S. Fish and Wildlife Service itself in the name

of protecting threatened and endangered species.

 

Environmental advocacy groups are also engaged in the creation and expansion of

wildlife corridors throughout North America and beyond. The Bozeman,

Montana–based American Wildlands, for instance, runs the Corridors of Life

project, which uses scientific modeling to locate the best potential public and

private lands for conversion to wildlife corridors throughout the Northern Rocky

Mountains. According to executive director Rob Ament, the group is working with

the government and with private landowners to protect parcels of land it deems

key to conserving viable populations of wild animals.

 

Meanwhile, the Richmond, Vermont–based Wildlands Project is also committed to

the establishment of a connected system of wild areas. Since its founding in

1991, the group has commissioned several scientific studies on the viability of

creating wildlife corridors and restoring populations of wolves and other ailing

species in different parts of North America.

 

The wildlife corridor concept is not limited to North America. Central American

nations have come together with leading conservation organizations including the

World Resources Institute and the Wildlife Conservation Society to create the

Mesoamerican Biological Corridor — also known as El Paseo Pantera ( " The

Pantherís Path " ) — to link key wildlife habitat from Mexico to Panama.

 

Many conservationists feel that this project is an important experiment " because

it is taking place in poor tropical countries where the greatest diversity of

life exists but where biodiversity is also under the greatest threat, " said

preeminent Canadian environmentalist David Suzuki, who hopes that someday the

concept can expand to South America, Asia, and Africa.

 

 

Got an environmental question? Mail it to: EarthTalk, c/o E/The Environmental

Magazine, P.O. Box 5098, Westport, CT 06881. Or submit your question at

www.emagazine.com or email us at earthtalk.