Soil Sodium Toxicity (depth to toxic layer)

High natural levels of sodium, that are toxic to some plants, are typically associated with deep subsoil sodicity, high pH, high boron and moderate salinity, and occur mostly in drier parts of the state. Mapping shows the depth to sodium toxicity of the most severely affected portion of the map unit (provided they occupy at least 30%), while detailed proportion data are supplied for calculating respective areas of each depth to sodium toxicity class (spatial data statistics).