Soils can be affected by salinity but are also an important part of salinity management because they are the buffer between rainfall and groundwater recharge. The infiltration rate of the soil and its depth influence the amount of water entering the groundwater system. Soils that are thin, porous and highly permeable allow water to pass through the soil to the groundwater system easily. These soils can only store small amounts of water and water will leak through them quickly. For example, water moves through sandy soils quickly because the pores that hold water are usually connected. In clay soils the pores that hold water are not usually connected so water passes through clay soils slowly.
The amount of organic matter in the soil can also influence the amount of water entering the groundwater system. The vegetation and micro-organisms living in the soil create a 'soil sponge' that improves the water holding capacity of the soil, thereby reducing leakage to the groundwater system.
In addition, soils with a high salt content also contribute to the occurrence of surface salinity.
Page last updated: 26 February 2011