.



FARMING CLAIMS ALMOST HALF EARTH'S LAND, NEW MAPS SHOW
By James Owen
National Geographic News
December 9, 2005

http://news.nationalgeographic.com/news/2005/12/1209_051209_crops_map.html

Food production takes up almost half of the planet's land surface and
threatens to consume the fertile land that still remains, scientists warn.

The global impact of farming on the environment is revealed in new maps,
which show that 40 percent of the Earth's land is now given over to
agriculture.

University of Wisconsin-Madison scientists compiled the maps using satellite
images and crop and livestock production data from countries around the
world. The team presented their picture of global land use this week at a
meeting of the American Geophysical Union in San Francisco.

"The satellite data tells us where cultivation is occurring with good
spatial accuracy, while the census data is able to tell us what is being
grown there," said Navin Ramankutty, a land-use researcher with
Wisconsin-Madison's Center for Sustainability and the Global Environment
(SAGE).

The maps suggest that an area roughly the size of South America is used for
crop production, while even more land -- 7.9 to 8.9 billion acres (3.2 to
3.6 billion hectares) -- is being used to raise livestock.

And with the world's population growing rapidly, the pressure is on farmers
to find new land to cultivate, the study team says.

"How can we continue to produce food from the land while preventing negative
environmental consequences, such as deforestation, water pollution, and soil
erosion?" Ramankutty said.

Past Picture

The researchers also used past land-use data to create maps showing how
agriculture has spread over the centuries. In 1700, for example, just 7
percent of the world's land was used for farming.

Figures from the Food and Agriculture Organization of the United Nations
suggest that total farmland increased by 12.4 million acres (5 million
hectares) annually between 1992 and 2002.

The SAGE scientists identified specific crops that help account for this
growth.

In Brazil, for example, huge areas of rain forest have been replaced by
soybeans, which aren't a traditional crop in South America. Production has
been fueled by demand for soy from China.

Brazil's Mato Grosso state has seen the biggest expansion of soybean
farming. A study by researchers at the University of Maryland found that 72
percent of land cleared for crops in that region between 2001 and 2003 was
previously pasture for livestock.

"It is not clear how much of this expansion is replacing forests versus
other land cover," Ramankutty said. "However, it is very likely that these
pastures were formerly rain forest. So the transition may have been from
forest to pasture to soybeans."

SAGE researcher Amato Evan said, "If current trends continue, we should
expect to see increased agricultural production at the cost of increased
tropical deforestation."

"And the production that is really driving the tropical cropland expansion
are crops that are used as feed for cattle."

Farmland Potential

Countries with the least suitable agricultural lands are likely to be the
ones hardest hit by increased food demand.

The team identified 16 such regions by comparing remaining potential arable
land with projected population growth over the next 45 years. The regions
include several parts of Asia, North Africa, and the Middle East.

"Most of the best lands are already cultivated, for sure," Ramankutty said.
"But by some estimates, we can potentially double the amount of cultivated
land by using the unrealized potential in Latin America and Africa."

He says, however, that these remaining unexploited areas are not necessarily
best suited for agriculture, and that using them for farming would often
mean clearing valuable natural ecosystems.

"I don't think we are in danger of running out of food," Ramankutty said.
"The issue is about what we are going to do to the environment in the
process of producing that food."

One potential solution could be "precision farming." The model uses new
technology to improve productivity while reducing the use of water and the
application of fertilizer and other potentially harmful chemicals.

According to Evan, heavy fertilizer use is a major problem in farming areas,
such as Madison, where the runoff pollutes nearby lakes.

The precision system, currently being developed by NASA geoscientists, would
work by using satellite data to help farmers decide how to use their
resources with pinpoint accuracy based on the requirements of different
areas of each field.

Meanwhile, the next phase of the SAGE project is to build an Internet-based
database called the Earth Collaboratory. The resource would draw on the
knowledge of scientists, local environmentalists, and the general public to
help design localized plans for land use.

Jonathan Foley, director of SAGE, said the project "will truly be a brave
new experiment that effectively bridges science, decision-making, and
real-world environmental practice -- collectively envisioning a new way to
live sustainably."

------------

NHNE News List:

To subscribe, send a message to:
nhnenews-subscribe@yahoogroups.com

To unsubscribe, send a message to:
nhnenews-unsubscribe@yahoogroups.com

To review current posts:
http://groups.yahoo.com/group/nhnenews/messages

Published by David Sunfellow
NewHeavenNewEarth (NHNE)
eMail: nhne@nhne.com
NHNE Website: http://www.nhne.com/
Phone: (928) 282-6120
Fax: (815) 642-0117

Appreciate what we are doing?
You can say so with a tax-deductible donation:
http://www.nhne.com/main/donations.html

P.O. Box 2242
Sedona, AZ 86339