Irrigation and Salinity Glossary of Terms

ECe. Soil salinity is measured as the salt concentration of a soil solution in terms of electrical conductivity (EC). For soil salinity, the EC is written as ECe. 

Irrigation. Providing water to soil in order to create a favorable environment for plants.

Leaching. Dissolving and transporting excess soluble salts from the root zone of the soil by applying and then draining excess water in the grove.

Salination. Increasing the salt content of soil. Salination can be caused by natural processes such as weathering, erosion and evaporation of water. Salts can also be transported to the soil surface by the capillary actions of a salt-laden water table. When the plants utilize the water, or when water evaporates from the soil, the salt is left behind — leading to potential salination. Salination can also be caused by irrigation with salt-laden water, water logging, land clearing, or the use of potassium as a fertilizer.

Saline soil. Soils that have a high salt content. Salty soils are common in arid and semi-arid regions due to a lack or precipitation. Soils with an ECe>4 are saline; 416 are considered severely saline.

Soil salinity. The salt content of the soil. 

Tensiometer. An instrument used to measure the water content of the soil. Water content is measured in units of pressure called centibars (cb).

Water logging. When lands are irrigated, it is impossible for plants to use 100% of the supplied water. The excess water usually seeps down to the underground water table, which can cause the water table to rise and lead to water logging. Water logging can decrease the oxygenation of the root zone because of the shallower water table, thus reducing crop yield. It can also lead to soil salination as more salt is brought to the surface by capillary action and less salt is removed by the aquifer that lies below the water table.