Dryland salinity means salinity in an area which is not irrigated. Primary salinity is not the result of human activity and is a natural part of some West Australian soils. Primary salinity is not considered an environmental problem.
Secondary salinity is an environmental problem.
Secondary salinity occurs when salt affects areas in which it was previously not a problem due to some change in the environment. This is especially common in land that has been cleared for agriculture. The increased levels of salinity can reduce the productivity of farm land and even make it completely infertile. See Figure 1. An example of salt affected land.