Edelstein, M., Department of Vegetable Crops, Agricultural Research Organization, Newe Ya'ar Research Center, Israel
Plaut, Z., Institute of Soil Water and Environmental Sciences, Volcani Center, 50 250 Bet Dagan, Israel
Ben-Hur, M., Institute of Soil Water and Environmental Sciences, Volcani Center, 50 250 Bet Dagan, Israel

Salinity is a significant problem in many regions in the world. It is estimated that the productivity of approximately 20-30 million irrigated hectares has been significantly decreased by salinity, and that salinization results in the annual loss of an additional 0.25-05 million hectares globally. The salts often originate from the earth's crust and from weathering, when irrigation is the main source for salts in soil. High sodicity may affect soil structure by decreasing soil aeration, leaching, and infiltration rate, and increasing runoff and soil erosion. The present paper reviews the effects of salinity and sodicity on soil structure and hydraulic properties in arid and semiarid regions.