salinization

(geology) In a soil of an arid, poorly drained region, the accumulation of soluble salts by the evaporation of the waters that bore them to the soil zone.

The build-up of salts at or near the surface of a soil. In hot, dry climates, evapotranspiration exceeds precipitation, so that surface water evaporates rapidly. This causes the soil moisture, together with its dissolved salts, to come to the surface by capillary action. This water then evaporates, leaving behind a crust of salts on the surface. This process occurs naturally in desert soils, but the incorrect use of irrigation in arid lands can cause salinization, which is a problem, for example, from the San Joaquin valley of California to the Punjab.

In coastal districts, salinization can occur when sea water percolates into the soil as a result of the over-pumping of groundwater.