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Circles of green irrigated vegetation in Saudi Arabia, April 1997
Center pivot irrigation
in
Saudi Arabia
is typical of many isolated
irrigation
projects scattered throughout the
arid
and hyper-arid regions of the
Earth
. Nonrenewable
fossil water
is mined from depths as great as 1 km (3,000 ft), pumped to the surface, and distributed via large
center pivot irrigation
feeds. The circles of green irrigated vegetation may comprise a variety of agricultural commodities from
alfalfa
to
wheat
. Diameters of the normally circular fields range from a few hundred meters to as much as 3 km (1.9 mi).
The projects often trace out a narrow, sinuous, and seemingly random path. Actually, engineers generally seek ancient river channels now buried by the sand seas. The fossil waters mined in these projects accumulated during periods of wetter climate in the
Pleistocene
glacial epochs, between 10,000 and 2 million years ago, and are not being replenished under current climatic conditions. The projects, therefore, will have limited production as the reservoirs are drained.
Saudi Arabia is the third most water stressed country in the world.
[1]
A network of
dams
has been built to trap and use precious seasonal
floods
. Vast underground water reservoirs have been tapped through deep wells.
Desalination
plants have been built to produce fresh water from the sea for urban and industrial use, thereby freeing other sources for agriculture. Facilities have also been put into place to treat urban and industrial run-off for agricultural irrigation. These efforts collectively have helped transform vast tracts of the
desert
into fertile
farmland
. Land under cultivation grew from under 400,000 acres (1,600 km
2
) in 1976 to more than 8 million acres (32,000 km
2
) in 1993.
Saudi Arabia is suffering from a major depletion of the water in its underground aquifers and a resultant break down and disintegration of its agriculture as a consequence.
[2]
[3]
As a result of the catastrophe, Saudi Arabia has bought agricultural land in the United States,
[4]
[5]
Argentina,
[6]
and Africa.
[7]
[8]
[9]
[10]
Saudi Arabia ranked as a major buyer of agricultural land in foreign countries.
[11]
[12]
See also
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References
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