May 23, 2001-2
Copyright © 2001 Earth Policy Institute
Dust Bowl Threatening Chinas Future
Lester R. Brown
On April 18, scientists at the National Oceanic
and Atmospheric Administration (NOAA) laboratory in Boulder, Colorado,
reported that a huge dust storm from northern China had reached
the United States blanketing areas from Canada to Arizona
with a layer of dust. They reported that along the foothills
of the Rockies the mountains were obscured by the dust from China.
Dust Storm in Northwest China, Mongolia,
North and South Korea April 7, 2001
VEGETATION PROGRAMME
Copyright © CNES 2001
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This dust storm did not come as a surprise. On
March 10, 2001, The Peoples Daily
reported that the seasons first dust storm one of the
earliest on record had hit Beijing. These dust storms, coupled
with those of last year, were among the worst in memory, signaling
a widespread deterioration of the rangeland and cropland in the
countrys vast northwest.
These huge dust plumes routinely travel hundreds
of miles to populous cities in northeastern China, including Beijing,
obscuring the sun, reducing visibility, slowing traffic, and closing
airports. Reports of residents in eastern cities caulking windows
with old rags to keep out the dust are reminiscent of the U.S. dust
bowl of the 1930s.
Eastward moving winds often carry soil from Chinas
northwest to North Korea, South Korea, and Japan, countries that
regularly complain about dust clouds that both filter out the sunlight
and cover everything with dust. Responding to pressures from their
constituents, a group of 15 legislators from Japan and 8 from South
Korea are organizing a tri-national committee with Chinese lawmakers
to devise a strategy to combat the dust.
News reports typically attribute the dust storms
to the drought of the last three years, but the drought is simply
bringing a fast-deteriorating situation into focus. Human pressure
on the land in northwestern China is excessive. There are too many
people, too many cattle and sheep, and too many plows. Feeding 1.3
billion people, a population nearly five times that of the United
States, is not an easy matter.
In addition to local pressures on resources, a
decision in Beijing in 1994 to require that all cropland used for
construction be offset by land reclaimed elsewhere has helped create
the ecological disaster that is now unfolding. In an article in
Land Use Policy, Chinese geographers Hong Yang and Xiubein Li describe
the environmental effects of this offset policy. The fast-growing
coastal provinces, such as Guandong, Shandong, Xheijiang, and Jiangsu,
which are losing cropland to urban expansion and industrial construction,
are paying other provinces to plow new land to offset their losses.
This provided an initial economic windfall for provinces in the
northwest, such as Inner Mongolia (which led the way with a 22-percent
cropland expansion), Gansu, Qinghai, Ningxia, and Xinjiang.
As the northwestern provinces, already suffering
from overplowing and overgrazing, plowed ever more marginal land,
wind erosion intensified. Now accelerating wind erosion of soil
and the resulting land abandonment are forcing people to migrate
eastward, not unlike the U.S. westward migration from the southern
Great Plains to California during the Dust Bowl years.
While plows are clearing land, expanding livestock
populations are denuding the land of vegetation. Following economic
reforms in 1978 and the removal of controls on the size of herds
and flocks that collectives could maintain, livestock populations
grew rapidly. Today China has 127 million cattle compared with 98
million in the United States. Its flock of 279 million sheep and
goats compares with only 9 million in the United States.
In Gonge County in eastern Quinghai Province,
the number of sheep that local grasslands can sustain is estimated
at 3.7 million, but by the end of 1998, sheep numbers there had
reached 5.5 million, far beyond the lands carrying capacity.
The result is fast-deteriorating grassland, desertification, and
the formation of sand dunes.
In the New York Times,
Beijing Bureau Chief Erik Eckholm writes that the rising sands
are part of a new desert forming here on the eastern edge of the
Quinghai-Tibet Plateau, a legendary stretch once known for grass
reaching as high as a horses belly and home for centuries
to ethnic Tibetan herders. Official estimates show 900 square
miles (2,330 square kilometers) of land going to desert each year.
An area several times as large is suffering a decline in productivity
as it is degraded by overuse.
In addition to the direct damage from overplowing
and overgrazing, the northern half of China is literally drying
out as rainfall declines and aquifers are depleted by overpumping.
Water tables are falling almost everywhere, gradually altering the
regions hydrology. As water tables fall, springs dry up, streams
no longer flow, lakes disappear, and rivers run dry. U.S. satellites,
which have been monitoring land use in China for some 30 years,
show that literally thousands of lakes in the North have disappeared.
Deforestation in southern and eastern China is
reducing the moisture transported inland from the South China Sea,
the East China Sea, and the Yellow Sea, writes Wang Hongchang, a
Fellow at the Chinese Academy of Social Sciences. Where land is
forested, the water is held and evaporates to be carried further
inland. When tree cover is removed, the initial rainfall from the
inland-moving, moisture-laden air simply runs off and returns to
the sea. As this recycling of rainfall inland is weakened by deforestation,
rainfall in the interior is declining.
Reversing this degradation means stabilizing population
and planting trees everywhere possible to help recycle rainfall
inland. It means converting highly erodible cropland back to grassland
or woodland, reducing the livestock population, and planting tree
shelter belts across the windswept areas of cropland, as U.S. farmers
did to end dust storms in the 1930s.
In addition, another interesting option now presents
itself the use of wind turbines as windbreaks to reduce wind
speed and soil erosion. With the cost of wind-generated electricity
now competitive with that generated from fossil fuels, constructing
rows of wind turbines in strategic areas to slow the wind could
greatly reduce the erosion of soil. This also affords an opportunity
to phase out the use of wood for fuel, thus lightening the pressure
on forests.
The economics are extraordinarily attractive.
In the U.S. Great Plains, under conditions similar to Chinas
northwest, a large advanced design wind turbine occupying a tenth
of a hectare of land can produce $100,000 worth of electricity per
year. This source of rural economic regeneration fits in nicely
with Chinas plan to develop the impoverished northwest.
Reversing desertification will require a huge
effort, but if the dust bowl continues to spread, it will not only
undermine the economy, but it will also trigger a massive migration
eastward. The options are clear: Reduce livestock populations to
a sustainable level or face heavy livestock losses as grassland
turns to desert. Return highly erodible cropland to grassland or
lose all of the lands productive capacity as it turns to desert.
Construct windbreaks with a combination of trees and, where feasible,
wind turbines, to slow the wind or face even more soil losses and
dust storms.
If China cannot quickly arrest the trends of deterioration,
the growth of the dust bowl could acquire an irreversible momentum.
What is at stake is not just Chinas soil, but its future.
(45k, approx. 11 sec at 33.6 speed)
Copyright
© 2001 Earth Policy Institute
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FOR ADDITIONAL INFORMATION
Hou Dongmin, Duan Chengrong, and Zang Dandan, Grassland
Ecology and Population Growth: Striking a Balance, China
Population Today, June 2000.
Drought Promotes Sandstorms in North China, Peoples
Daily, 10 March 2001.
Erik Eckholm, Chinese Farmers See a New Desert Erode their
Way of Life, New York Times, 30 July 2000.
Wang Hongchang, Deforestation and Desiccation in China: A Preliminary
Study (Beijing, China: Center for Environment and Development,
Chinese Academy of Social Sciences), 1999.
National Center for Atmospheric Research (NCAR), Scientists,
Ships, Aircraft to Profile Asian Pollution and Dust, NCAR
Press Release, 20 March 2001.
National Oceanic & Atmospheric Administration (NOAA), China
Dust Storm Strikes USA, NOAA News, 18 April 2001.
Michael C. Runnstrom, Is Northern China Winning the Battle
Against Desertification? Ambio, December 2000.
Hong Yang and Xiubin Li, Cultivated Land and Food Supply in
China, Land Use Policy, v. 17, n. 2, 2000.
Dong Zhibao, Wang Xunming, Liu Lianyou, Wind Erosion in Semiarid
China: an Overview, Journal of Soil and Water Conservation,
v. 55, n. 4, 2000.
LINKS
American Wind Energy Association
http:/www.awea.org
United Nations Development Programme Office to Combat Desertification
and Drought
http:/www.undp.org/seed/unso
United Nations Food and Agriculture Organization on-line database
http:/apps.fao.org
United Nations Secretariat of the Convention to Combat Desertification
http:/www.unccd.int
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