Disappearing drylands spell trouble says UN
Rhett A. Butler, mongabay.com
March 21, 2006
According to the United Nations, the continuing degradation of the world’s dryland ecosystems is threatening biodiversity and worsening poverty around the globe. In an effort to bring attention to the dire condition of these important lands, which cover almost half the planet’s land surface, the world organization has proclaimed 2006 the International Year of Deserts and Desertification.
47% of the Earth’s land area is drylands. This includes arid and semi-arid zones like Africa’s Sahara and the Horn of Africa; savannahs like the cerrado of Brazil, Eurasian steppes and the North American Great Plains; and Mediterranean landscapes like those found in California and Europe. These ecosystems receive very erratic rainfall, making them especially vulnerable to drought and catastrophic flooding. Despite their fragile nature, drylands are key to the livelihoods of almost 2 billion people as well as countless species.
Photo by R. Butler
The UN says that biodiversity in these ecosystems is under threat from a variety of human activities, including the transformation of wildlands for human use and increases in overexploitation of resources. Overgrazing and agricultural conversion has resulted in the degradation of up to 20% of drylands ecosystems, producing desertification and drought, and worsening the quality of life for millions whose day to day survival is dependent upon natural resource use from these already marginal lands. While the UN pegs the cost of this degradation at more than 40 billion dollars a year in lost agricultural production, the true cost—measured by failing water resources, rising political tensions, increasing social instability—is likely far higher. Amid projections that the world will see as 50 million people escaping the effects of environmental deterioration by 2100, the UN believes steps must be taken immediately to stave off long-term consequences.
The UN says the urgency of these issues makes it imperative to set take specific actions to reduce the rate of biodiversity loss by the year 2010. These include reducing overgrazing in delicate ecosystems, cutting pollutants generated by intensive agriculture, slowing the conversion of grassland and savannah systems to agriculture and urban settlement, controlling invasive species alien to these ecosystems, and helping to build institutions that alleviate poverty by enabling the poor to realize “sustainable livelihoods.”
These, and other ideas for conserving natural areas, are presently being discussed at the Convention on Biological Diversity summit in Curitiba, Brazil. More than 3000 delegates and 100 government ministers in charge of biodiversity have gathered to assess the outlook for Earth’s species.
This article used information from press materials provided by the UN.