What are the causes of Soil Salinity?
Numerous factors contribute to salinity in the soils of Australia. In our earlier, wetter history, the country’s interior hosted inland seas. As those seas evaporated they left vast salt deposits in their wake. However, the most significant factor is the airborne salt that is mobilised via wind over the oceans and has, for millions of years, deposited over inland areas in rain and dust. Airborne salt affects coastal areas and stretches far inland in parts of Western Australia and South Australia. Figure Two: Typical changes in water and salt balances following clearing (for a catchment with rainfall of approximately 700 mm per annum) Source: http://www.wrc.wa.gov.au/protect/Salinity/ Irrigation and land clearance for agriculture has compounded the problem of increasing salt content in soils by creating an imbalance in the volume of water deposited (recharge) relative to that which is used (discharge). Rainwater percolates into and is suspended in the subsoil. The surface of that ground
