07/14/01 -- The Importance of Land Use to Global Ecological Sustainability

***********************************************

FOREST CONSERVATION NEWS TODAY

The Importance of Land Use to Global Ecological Sustainability

***********************************************

Forest Networking a Project of Forests.org, Inc.

http://forests.org/ -- Forest Conservation Portal

http://forests.org/links/ -- Forest Conservation Links

07/14/01

OVERVIEW & COMMENTARY by Forests.org

The extent to which humans have altered terrestrial ecosystems is

truly remarkable as well as ecologically tragic. An extremely

important new study by University of Wisconsin researchers highlights

the extent to which people have influenced the Earth's land resources

over the past 300 years. Consider for a moment: 12 percent of the

global land surface is now under permanent cultivation, half of the

world's supply of fresh water is now appropriated by humans, carbon

dioxide concentrations have risen by nearly a third, and at least 20

percent of the world's forests and woodlands have disappeared. The

degree to which humans have reshaped global landscapes is largely

responsible for declines in atmospheric, marine and aquatic

ecosystems as well. It is time to protect all remaining forest

wildlands from commercial development, sustainably manage and assist

the regeneration of all secondary forests, and bring the human

landscape into a greater state of ecological sustainability through

restoration and rehabilitation of degraded lands, organic

agriculture, permaculture and other restorative land uses. Global

ecological sustainability starts with how we treat the land.

g.b.

*******************************

RELAYED TEXT STARTS HERE:

Title: Is Land Use Even More Important Than Global Warming?

http://unisci.com/

Date: July 12, 2001

Byline: By Navin Ramankutty, Terry Devitt

Over the past 300 years, in an ever-accelerating process, humans have

reshaped the terrestrial surface of the Earth.

In doing so, humanity has scripted a scenario of global environmental

change with impacts that promise to be at least as severe as global

climate change, scientists reported in Amsterdam Wednesday.

Addressing an open science conference held under the auspices of the

International Geosphere-Biosphere Programme, University of Wisconsin-

Madison

environmental scientist Navin Ramankutty and colleague Kees Klein

Goldewijk of the Dutch National Institute of Public Health in

Amsterdam unveiled a historical global land-use inventory that

chronicles the massive impact humans have had as they've remade the

global landscape since the 17th century.

"We're hitting a threshold of available global natural resources,"

Ramankutty says. "We need to think about this issue before it's too

late. There is no substitute for natural resources."

By far, the largest human influence on the global landscape is

agriculture with

12 percent of the global land surface -- an area equivalent to the

surface area of all of South America -- now under permanent

cultivation, says Ramankutty.

Moreover, a global trend toward urbanization promises to "become one

of the biggest consumers of land," predicts Ramankutty.

"Historically, we lost forest to crop land. Now we are losing crop

land to urban areas."

To take stock of how the Earth's land resources have been influenced

by people over the past 300 years, Ramankutty and Wisconsin

climatologist Jonathan Foley embarked on a massive study of

historical records, combining such things as agricultural land

surveys, tax rolls and census data to sketch a portrait of global

landscape change that, for the most part, has gone unrecorded in any

direct way by the world's governments.

To augment the historical records, Ramankutty and Foley used growing

repositories of satellite-derived land cover data sets that have

recorded a broad spatial picture of human land-use and land-use

change over the past 20 years.

The resulting database, made available in Amsterdam in CD ROM format

along with a Dutch database, represents the first dynamic picture of

global land use for the 300-year period between the beginning of the

18th century and today.

The database, says Ramankutty, is intended to provide a comprehensive

picture of the growing dominance of human land use on global land-

cover patterns. Data sets, he notes, could be used within global

climate models and global ecosystem models to gain insight into the

influence of land cover change on climate and biological and

geochemical cycles.

In a related study, also presented by Ramankutty at the Amsterdam

conference, it was shown that between 1860 and 1992, changes in land

use contributed significantly to the build-up of atmospheric carbon

dioxide, a major greenhouse gas.

These are key issues related to land use and there's now a sense of

urgency, says Ramankutty, as humans lock up the dwindling supply of

the world's natural resources and change the chemical makeup of the

atmosphere.

For example:

* Half of the world's supply of fresh water is now appropriated by

humans.

* Since 1700, nearly 20 percent of the world's forests and woodlands

have disappeared.

* Atmospheric carbon dioxide concentrations have risen by nearly a

third since the industrial revolution.

"Knowing exactly what has changed and by how much, what are the

historical patterns of change, and what are the consequences of

change, are now key questions that we have to answer," says

Ramankutty.

The situation will worsen, he says, as world population continues to

soar and the per capita consumption of goods and services derived

from the natural resource base also continues to grow.

Moreover, in some parts of the world, intensive agriculture is

exhausting the land, permanently removing acreage from production and

the natural resource base.

The development of the global land-use database was supported by NASA

and the Electric Power Research Institute.

The Amsterdam conference, "Challenges of a Changing Earth," is co-

sponsored by three large international global change research

programs: the International Geosphere-Biosphere Programme, the

International Human Dimensions Programme and the World Climate

Research Programme.

Center for Sustainability and the Global Environment

http://sage.aos.wisc.edu/

###RELAYED TEXT ENDS###

In accordance with Title 17 U.S.C. Section 107, this material is

distributed without profit to those who have expressed a prior

interest in receiving forest conservation informational materials for

educational, personal and non-commercial use only. Recipients should

seek permission from the source to reprint this PHOTOCOPY. All

efforts are made to provide accurate, timely pieces, though ultimate

responsibility for verifying all information rests with the reader.

For additional forest conservation news & information please see the

Forest Conservation Portal at URL= http://forests.org/

Networked by Forests.org, Inc., gbarry@forests.org