The Aral sea is located in Central Asia between Kazakstan and Uzbekistan. It once covered 25,659 sq mi (66,457 sq km) and was the fourth largest inland body of water in the world.One of the large irrigation areas is the Amu-Dar'ja delta in the south of the The Aral sea. The irrigated area extends over approximately 28000 sq km, and is mainly used for the cash crops cotton and rice. In the 20th century the irrigated area in the The Aral sea region increased from about 3 Mio ha to over 8 Mio ha today. Along the former shoreline salt has accumulated dueto evaporation and solonchaks have developed. As a result of the strong NE winds in this area, the salt is picked up and transported by aeolic processes and through deflation lands on the irrigated fields in the south. In addition the north of the Amu-Dar'ja delta used to be an important ecosystem with a large variety of flora and fauna. The increasing salinity and the water shortage have led to a vast degradation of these areas. In addition the productivity of the agricultural fields dropped significantly due to secondary salinization as a result of capillary uprising of soil.