Soil salinity is the salt content in the soil; the process of increasing the salt content is known as salinization.Salt is a natural element of soils and water. Salinization can be caused by natural processes such as mineral weathering or the gradual withdrawal of an ocean. It can also be caused by artificial processes such as irrigation.

Salt-affected soils are caused by excess accumulation of salts, typically most pronounced at the soil surface. Salts can be transported to the soil surface by capillary transport from a salt laden water table and then accumulate due to evaporation. They can also be concentrated in soils due to human activity, for example the use of potassium as fertilizer, which can form sylvite, a naturally occurring salt. As soil salinity increases, salt effects can result in degradation of soils and vegetation.

Salinization is a process that results from:

Salt is a natural element of soils and water. The ions responsible for salinization are: Na⁺, K⁺, Ca²⁺, Mg²⁺ and Cl^-.
As the Na⁺ (sodium) predominates, soils can become sodic. Sodic soils present particular challenges because they tend to have very poor structure which limits or prevents water infiltration and drainage.

Major General Philip Michael Jeffery AC, CVO, MC (born 12 December 1937) was the 24th Governor-General of Australia (2003–2008), the first Australian career soldier to be appointed governor-general. He had previously served as Governor of Western Australia (1993–2000).

Michael Jeffery was born in Wiluna, Western Australia and was educated at Kent Street Senior High School. At 16 he left Perth to attend the Royal Military College, Duntroon, in Canberra. After graduation in 1958, he served in a number of junior positions before being posted to Malaya in 1962 for operational service. From 1966 to 1969 he served in Papua New Guinea. During this posting, he married Marlena Kerr of Sydney, with whom he had three sons and a daughter. This was followed by a tour of duty in Vietnam during which he was awarded the Military Cross (MC). Jeffery remained convinced that Australia's participation in the Vietnam War was right. "I believe passionately that Vietnam was a just cause in the circumstances of the time", he said during a 2002 speech to Australian veterans of the war.