Mediterranean Nations Share Knowledge to Halt Desertification

COPENHAGEN, Denmark, September 27, 2000 (ENS) - Considerable areas of land bordering the Mediterranean will be lost beyond salvage to desertification within 50 to 75 years, a United Nations agency said today.

The Secretariat of the United Nations Convention to Combat Desertification (UNCCD) does not specify how much "considerable" means but bases its "tentative" estimates on current rates of erosion brought on by climate change, land use changes and other human activities. The Secretariat administers the international agreement that targets the Earth's spreading deserts.

desert

The linear dunes of the Sahara Desert encroach on Nouakchott, the capital of Mauritania. (Photo by Georg Gerster, courtesy U.S. Geological Survey)
Together with the European Environment Agency and the Italian Foundation for Applied Meteorology, UNCCD executive secretary Hama Arba Diallo announced today the creation of a Desertification Information System in an effort to reverse the trend.

At the United Nations Conference on Desertification in 1978, desertification was defined as a "diminution or destruction of the biological potential of the land which can lead ultimately to desert like conditions."

The Earth is covered by a fragile layer of soil which forms slowly, but can be blown and washed away in a few seasons. When this process can no longer be compensated for by nature's inherent ability to recover, desertification follows.

Nowhere is the problem more acute than in arid, semi-arid and dry sub-humid areas, which cover more than one third of the Earth's surface.

Land covers 14.9 billion hectares of the earth's surface. A United Nations Environment Programme study shows that 6.1 billion hectares are dryland of which one billion hectares are naturally hyperarid desert.

The rest of the dryland has either become desert or is being threatened by desertification.

One quarter of the world's people inhabit the drylands and depend on this area for their livelihood.

Desertification strips susceptible areas of their productive capacity and often leads to food shortages and poverty.

Adopted in 1994, as a direct result of the 1992 UN Earth Summit in Rio de Janeiro, the Convention to Combat Desertification is the first international treaty to attempt to deal with the effects of desertification and come up with solutions. Today's announcement in Copenhagen of a Desertification Information System is one attempt at a solution.

"All countries in the Mediterranean are affected by desertification and land degradation in some degrees," said Diallo. "However, the exact quantification, geographical distribution and total impact of such processes are only roughly known."

Diallo said the role of the new information system will be to involve all nations of the Mediterranean basin, as well as scientists and specialized institutions in sharing information on desertification.

erosion

Overgrazing has made the Rio Puerco Basin of central New Mexico one of the most eroded river basins of the American West and has increased the high sediment content of the river. (Photo by Terrence Moore, courtesy U.S. Geological Survey)
Better communication and a common information system will avoid duplication and help Mediterranean governments create more effective programs to deal with the problem.

Over the next three years, the Desertification Information System is expected to produce a common set of benchmarks and impact indicators, as well as vulnerability mapping and databases.

Although climate change is thought to be contributing to increasing desertification, historical evidence shows the problem is not new. Writing in a February 1990 edition of "New Scientist," regular contributor Sarah Bunney cites evidence of prehistoric desertification gleaned from lake sediments in the highlands of central Mexico.

The area experienced several episodes of devastating soil erosion after farmers' first attempts to cultivate maize on a wild scale 3,500 years ago.

"The effects of this destruction can be seen today on the steep-gullied hillsides that surround the lake [Patzcuaro] and in the fans of red soil redeposited around the lake shore," writes Bunney. "Where once there was abundant pine forest, now there is only impoverished shrub."

Bunney is editor of the "Cambridge Encyclopedia of Human Evolution."