Not available – first paragraph follows: Saline and sodic soils occur naturally in arid and semiarid regions, and as water development brings more land into irrigation, the salinity problem expands. The condition is aggravated by poor soil drainage, improper irrigation methods, poor water quality, insufficient water supply for adequate leaching, and insufficient disposal sites for water that leaches salts from the soil. Problems caused by soil salinity are compounded when a high water table impedes root development and concentrates salts in the already limited root zone.