Soil salination

From Envirowiki

Soil salination refers to the process whereby soil (usually on agricultural land) becomes saturated with salts. This kills a lot of the life in the soil, including microbes, invertebrates, plants, and, following down the food chain, insects, and other animals leave the area, or starve. Large areas can become barren due to salination.

Salination is caused by the water table rising to the surface, drawing up mineral salts from the sub strata, and depositing them on, or near the surface. Generally, this only happens in areas that are either cleared, or over-irrigated.

Large trees, especially eucalypts, which have deep roots, can help prevent soil salination by keeping the water table low.

Natural sequence farming is a process that keeps water in the landscape, and encourages the fast growing weeds, or colonising plants, in an effort to retain water in the soil, and prevent it rising to the surface, in pools. this can help prevent salination, as well as reducing the need for irrigation.