Salinization of Irrigated Soils in the Middle-Asian Region: Old and New Issues

Resumo

The article provides information on the genesis and distribution of saline soils in the Turan Plain region of middle Asia. It is demonstrated that, prior to the start of active irrigation in the 20th century, the modern salt-accumulation process was developed mainly in naturally hydromorphic soils. On floodplains, the process was regulated by natural floods; it has not developed actively in automorphic soils. Due to irrigation, natural automorphic soils have been transformed into irrigated hydromorphic soils. This resulted in the activation of salt-accumulation processes, even with a drainage of 2.5–3 m deep. In the 21st century, new issues arose in the region: a freshwater deficiency; increased eolic salt transfer; deteriorating climatic, environmental, and social conditions.