Definitions relating to salinity

Catchment

A catchment area or basin is land that is bounded by natural topographic features such as hills or mountains and from which all runoff water flows to a low point.

Discharge area

An area in the landscape where groundwater moves to the soil surface. Evidence of this includes salt scalds, seepage or waterlogging. Salt may also accumulate in a discharge area.

Dryland

Land use that relies on natural rainfall, not irrigation. Dryland salinity occurs where irrigation water is not a factor in changing the water balance.

Groundwater

Water below the surface of the landscape, occupying cavities and spaces in regolith and bedrock. The upper surface of the groundwater is the watertable.

Primary salinity

Salinity that occurs naturally in soils and waters.

Recharge area

Area where rainfall or flowing water infiltrates or 'leaks through' soil, sediments and rock into groundwater. Generally areas with permeable soils and weathered or fractured rock are areas of higher recharge.

Regolith

That part of the earth's surface including soil and weathered and fractured rock through which water and salts can flow.

Saline soil

Soil containing sufficient concentrations of soluble salts within the soil profile to result in reduced plant productivity or plant death. Climate, soil type, depth to salinity in the soil, and plant species influence the effect on plant productivity.

Saline water

Water that contains sufficient concentrations of soluble salts to limit potential for domestic supply, industry, agriculture and environmental uses.

Salinisation

The process of salts accumulating in soil or water. (Also called salting).

Salinity

The presence of soluble salts in soil or water.

Salinity hazard

The inherent characteristics of the landscape that predispose it to land and water salinity.

Salinity risk

The probability that land or water salinity may develop if certain management practices or land-use changes occur.

Secondary salinity

Salinity that results from human activities, usually land and infrastructure development and agriculture.

Water balance

The amount of water in the different parts of the water cycle including:

Watertable salting

Salinity that occurs where a shallow or seasonally shallow watertable is sufficiently close to the soil surface for groundwater to move up to the surface by capillary action or seepage. This results in the evaporative accumulation of salts in the root zone or on the soil surface. Shallow watertables can also allow water and salt to leak into rivers and streams. Watertable salting does not necessarily involve saline groundwater

Last reviewed 10 April 2012
Last updated 4 September 2008

Salinity