A leaching model is a hydrological model by which the leaching with irrigation water of dissolved substances, notably salt, in the soil is described depending on the hydrological regime and the soil's properties.
The model may describe the process (1) in time and (2) as a function of amount of water applied.
Leaching is often done to reclaim saline soil or to conserve a favorable salt content of the soil of irrigated land [1] as all irrigation water contains salts.