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Amu Darya River |
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Amu Darya River |
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This false-color image of the Amu Darya River was acquired by the Multi-angle Imaging SpectroRadiometer (MISR) in late June, 2002, and represents an area of about 292 kilometers x 370 kilometers. Data from the near-infrared, red and blue spectral bands of MISR's downward-viewing (nadir) camera are displayed as red, green and blue, respectively, causing highly vegetated areas to appear red.
The Amu Darya river forms a wide delta in the western deserts of Uzbekistan and northeastern Turkmenistan, and the river waters are utilized intensively to irrigate cotton and other crops. During the Soviet era, large irrigation systems were developed and the region became specialized in cotton growing. Independence from the Soviet Union occurred in 1991 and is celebrated by Uzbekistan on September 1st and by Turkmenistan on October 27th. Both of these landlocked countries are losing arable land to soil salinization as a result of rising groundwater levels that accompany crop irrigation.
As a consequence of the diversion of vast quantities of freshwater from the Amu Darya and Syr Darya rivers, water volume in the Aral Sea has dropped by more than 80% since 1960. Increases in water input near the river's source (from precipitation or glacial meltwater) do not compensate for the water lost from this shrinking inland sea. Commercial fishing in the region has ceased.
A portion of the border between western Uzbekistan and northeastern Turkmenistan follows the course of the Amu Darya river. Within the river system, about 50 fish species could be found during the 1960's; that number has dropped to approximately 20. Within the area of this image, the width of the main river is widest in the lower right-hand corner (closer to its source in the mountains of Afghanistan) and is greatly reduced by the time it reaches the edges of the dwindling Aral Sea. However, both the Amu Darya and the Aral Sea have experienced dramatic changes in response to past climate and probably also in response to historical irrigation practices. The new and old site of the city of Urgench is one indication of the river's dynamic nature. The river changed its course during the 17th century, prompting Urgench to relocate and re-build closer to the new riverbed.
Image credit: NASA/GSFC/LaRC/JPL, MISR Team.
