Soluble Salts

Soil salinity is described and characterized in terms of the concentrations of soluble salts. The management and need for reclamation of saline soils are evaluated from measurements of such concentrations. The appropriate method of measuring soil salinity must be selected for the specific condition and purpose. To monitor soil water salinity as the soil dries between irrigations, the salinity sensor is recommended. When determination of a particular solute is needed, then either collection or extraction of soil samples or collection of water samples is required. For some needs, knowing the composition of solutes in soil water at field water contents is desirable. However, present methods of obtaining soil water samples at usual field water contents are not practical for routine purposes. For these reasons, crop tolerance to salinity is often related to the electrical conductivity, or total electrolyte concentration, of the saturation extract.