Key deserts 'in danger'
2006-06-05 12:19
London - Far from being barren wastelands,
the deserts that occupy one quarter of the earth's land surface could be key sources of food and power, the United Nations said on Monday.
But these vast open spaces, home to rare and useful plants
and animals, are at risk from climate change and human
exploitation, the UN's Environment Programme said in a report
published on World Environment Day.
Deserts are prime potential locations for solar power
generators that do not pollute the atmosphere with greenhouse
gases, and plants that can thrive in desert conditions could
provide food when water runs short.
One such, a plant called Nipa found in the Sonoran desert of
western Mexico, produces a grain the size of wheat but is
drought resistant and even thrives on seawater.
"It is a strong candidate for a major global food crop and
could become this desert's greatest gift to the world," the report said.
Rainfall patterns are changing, glaciers that feed important
rivers are melting as the planet warms and irreplaceable water
from deep desert aquifers is being squandered.
Rainfall in Iran's Dashti Kibri desert dropped by 16%
a decade between 1976 and 2000. In South Africa's Kalahari and
Chile's Atacama deserts it fell by 12 and eight percent
respectively, the report said.
The Rio Grande river in the United States has dwindled to a
saline trickle from a freshwater torrent, and South Africa's
Orange river is also shrinking.
Fighting for water
"The answer to desert water is to stop using it stupidly,"
said specialist Andrew Warren of University College London.
"Saudi Arabia exports water in the wheat it grows using
irrigation ... Jordan exports much of its water in the form of
tomatoes," he added, noting that as over-exploited water sources
retreated, the water became more salty and less useable.
It said that in China's Tarim River basin more than 12 000
square km of land had been salinised over the
past 30 years.
The energy-intensive desalination plants which turn salt
water into fresh water in some energy-rich countries in the
Middle East are not generally attractive in an era when energy
prices are rising rapidly.
As well as biodiversity, human societies are at risk. The
cultures of desert dwellers around the world are threatened by
reduced rainfall and over-exploitation, and dwindling resources
could generate local wars, the report warned.
"There is going to be a fight for water - there already are
such fights," Warren said.
Pakistan, already one of the most water-stressed countries
in the world, is facing even more problems as groundwater levels
fall and glaciers retreat.
"There will be increased competition for water resources,"
Warren said. "It is not the most stable region. There will be
really nasty implications."