Soil Salinity

Soil salinity is the build-up of mineral salts on the soil surface. In Alberta, salts occur naturally in many bedrock deposits and in some deposits that lie on top of the bedrock. Groundwater flowing through these deposits dissolves and transports the salts.

Under certain conditions, this groundwater rises to the soil surface where the water evaporates and leaves the salts behind. Over time, salts accumulate in these discharge areas (saline seeps) and in high enough concentrations can prevent plant roots from taking up water and essential nutrients. This restricts plant growth and reduces crop yields.

Dryland salinity is considered to be a significant soil degradation problem on the Canadian Prairies. In Alberta, approximately 650,000 hectares of dryland are affected by salinity, causing an average crop yield reduction of 25 percent in affected areas. The extent and severity of the dryland salinity problem is increasing in some areas, and is particularly evident after a series of wet years.

Salinization of irrigated lands, especially in areas of solonetzic and saline soils, can also be a problem. The risk of salinization should be considered when planning irrigation programs.

Department of the Environment. State of the Environment Report, Terrestrial Ecosystems. Edmonton: n.p., 2001. With permission from Alberta Environment.