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CONTENTS
Vol. 4 N° 4
IN
FOCUS
p 2 - The future of drylands revisited
NEWS
p 9 - Nigerian President pledges
US$5 billion towards National Science Foundation
p 9 - UNESCO and the BBC bring science to the screen
p 10 - A regional biotechnology centre for India
p 11 - Experts appeal for greater sup-port for sea-level
rise research
p 11- National tsunami preparations an absolute priority
INTERVIEW
p 12 - Badaoui Rouhban
on making schools safe in a disaster
HORIZONS
p 15 - The very real success of the Avicenna Virtual
Campus
p 19 - Students choose life in Kenya
IN BRIEF
p 24 - Diary
p 24 - New releases
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Greening
the deserts
In
the 1950s, a sense of great optimism prevailed that we could
green the world's deserts. It was believed that techniques
like cloud seeding could bring rainfall to dry areas; improved
irrigation techniques could boost agricultural production
in dry-lands; and selective breeding could create livestock
less dependent on water. In short, we thought that poverty
in the world's drylands could be reduced through technology.
Half a century later, that optimism has been replaced by realism
and anxiety. The belief that we can control our climate has
given way to concerns about the human impact on the environment,
in particular global warming. Current climate scenarios predict
that the driest regions of the world will become even drier.
Only
last May, a study published in Science indicated that the
tropical climate zone was expanding towards both poles. According
to the study, which is based on satellite data from 1979 to
2005, the northern and southern hemispheres jet streams
fast-flowing winds about 10 km above the Earths
surface which mark the limits of the tropics have each
moved about 1° of latitude (about 113 km) nearer the poles.
If the jet streams move another 23° degrees
poleward this century, very dry areas like the Sahara Desert
could nudge farther towards the poles, perhaps by a few hundred
miles, predicts co-author John Wallace of the University
of Washington (USA).
Despite
technological advances in the genetic modification of organisms
to make them drought- and pest-resistant, dryland countries
are still among the poorest in the world; many also register
high population growth.
As
we shall see in this issue, the past 50 years have shown us
that the ecological and socio-economic situation in drylands
is not a simple equation governed by factors such as climate,
soil, water and vegetation. Market speculation and enormous
price fluctuations on commodities like cotton can affect the
income of a rural farmer in a remote village in Mali, in the
same way that droughts or floods will affect his or her harvest.
Policy
choices also enter into play. Nearly one-fifth of China is
desertic. Last February, the government announced an ambitious
plan to reclaim 250 000 km2 of desert by 2020 by planting
trees and grasses, banning land use in some areas and investing
in sustainable energy and efficient water use.
One
thing we have learnt over the past 50 years is that, if drylands
do not cover the globe, they are nevertheless a global problem.
To cite the authors of The Future of Drylands Revisited, dust
from central Asia causes health concerns not only in China
and Japan but also in North America [and] dust from Africa
may be contributing to the decline of coral reefs in the Caribbean.
W.
Erdelen
Assistant Director-General for Natural Sciences
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