What causes dryland salinity?
Primary salinity Australia is naturally a salty continent with limited capacity to drain salt and water. Some salt is released from weathering rocks (particularly those formed from marine sediments), and some is carried by rain from surrounding oceans and deposited on the soil and in the water. Primary salinity is caused by naturally occurring salt deposits. Secondary salinity Australia’s natural salinity has been intensified by changes in land use since European settlement. We have cleared much native vegetation and replaced it with crops and pastures that have shallower roots and different seasonal growth patterns. Crop and pasture plants use less water than native vegetation, therefore allowing more water to seep into the ground and travel down past the root zone and into the groundwater beneath the surface. This extra water makes the water table rise. As the water rises it dissolves the salts that are naturally in the soil, therefore the rising water becomes salty and contaminates
