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Posts tagged Desertification

Desertificatio and the Desiccated South Aral Sea

46.7N 61.6E

April 2nd, 2013 Category: Climate Change, Lakes

Aral Sea – April 1st, 2013

While water is present in the North Aral Sea, the South Aral Sea, which lies in poorer Uzbekistan, has been largely abandoned to its fate. Only excess water from the North Aral Sea is now periodically allowed to flow into the largely dried-up South Aral Sea through a sluice in the dike.

Discussions had been held on recreating a channel between the somewhat improved North and the desiccated South, along with uncertain wetland restoration plans throughout the region, but political will is lacking. Uzbekistan shows no interest in abandoning the Amu Darya river as an abundant source of cotton irrigation, and instead is moving toward oil exploration in the drying South Aral seabed.

Attempts to mitigate the effects of desertification include planting vegetation in the newly exposed seabed; however, intermittent flooding of the eastern basin is likely to prove problematic for any development. Redirecting what little flow there is from Amu Darya to the western basin may salvage fisheries there while relieving the flooding of the eastern basin.

Desertification Leading to More Dust Storms in Aral Sea Region – March 24th, 2013

46.7N 61.6E

March 24th, 2013 Category: Climate Change, Dust Storms, Image of the day, Lakes

Aral Sea – March 23rd, 2013

The region around the Aral Sea, whose water levels have dropped 23 meters since the onset of water diversion from its primary sources, has experienced significant desertification. The desertification is characterized by degradation of the land and natural resources to the point that they can no longer be used.

Several factors influence the desertification, including the decline in the groundwater level. By cutting off water supply to a region, the hydrological balance of the area becomes offset as more water leaves the region than is coming into the region.

Frequent low-water periods contributed to the shortfall of needed resources for vegetation. The decline in the groundwater level in the Amudarya and Syrdarya deltas contributed to the piling up of salt at the surface. This increase in salt content was later accompanied by a change in vegetative cover because the plants began to die away as a result of the increased salinity of the sea. As a result, vegetation in the region was reduced by at least 40%. Six million hectares of agricultural land were destroyed as a result of salinization and desertification (click here for more information).

A side effect of the decrease in the protective vegetation cover was intensified winds, which led to more dust storms in the area. Here, dust can be seen blowing across the southwestern basin of the lake and across the northern part of nearby Sarygamysh Lake.

Dust Storm on Eastern Edge of Taklamakan Desert, China

39.5N 90.0E

March 18th, 2013 Category: Climate Change, Dust Storms

China – March 11th, 2013

A duststorm affects the Taklamakan Desert in western China, particularly by its eastern edge. The Taklamakan is China’s biggest desert and is an immense sea of shifting sand dunes, which dominates the west of the country.

The fringes of the desert are most susceptible to desertification, as overgrazing on farmland bordering the desert tends to strip the lands of their grass and hence allows the desert to take hold and expand. During the spring, winds tend to increase in intensity in the west of China. As the spring winds blow, they pick up the sand and dust lying on top of the degraded land and carry it into the air, creating these massive dust and sand storms.

Low Water Levels in Eastern Basin of South Aral Sea – August 14th, 2012

46.7N 61.6E

August 14th, 2012 Category: Environmental Disasters, Image of the day, Lakes

Aral Sea – August 13th, 2012

As the Aral Sea has shrunk, it has separated into three distinct main lakes. Here, the North Aral Sea and the western lake of the southern basin appear to contain significantly more water than the eastern lake.

The ecosystems of the Aral Sea and the river deltas feeding into it have been nearly destroyed, not least because of much higher salinity. The receding sea has left huge plains covered with salt and toxic chemicals – the results of weapons testing, industrial projects, pesticides and fertilizer runoff – which are picked up and carried away by the wind as toxic dust and spread to the surrounding area.

Crops in the region are destroyed by salt being deposited onto the land. Vast salt plains exposed by the shrinking Aral have produced dust storms, making regional winters colder and summers hotter The land around the Aral Sea is heavily polluted, and the people living in the area are suffering from a lack of fresh water and health problems, including high rates of certain forms of cancer and lung diseases.

Salt Flats in Remains of Aral Sea

June 17th, 2012 Category: Salt Flats

Aral Sea - May 19th, 2012

The remains of the Aral Sea, once one of the four largest lakes in the world with an area of 68,000 square kilometres (26,300 sq mi), appear mainly as a large salt pan flanked by small bodies of water in the basins to the west and north. By 2007, the lake had declined to 10% of its original size, splitting into four lakes. By 2009, the southeastern lake had disappeared and the southwestern lake retreated to a thin strip at the extreme west of the former southern sea. The maximum depth of the North Aral Sea is a mere 42 m (138 ft) (as of 2008).