Sustainability

Salinization

Saline soils form when the water leaves the ground mainly due to evaporation, transpiration, or percolation. This mainly occurs in dry areas, where precipitations are not sufficient to eliminate the salt from the ground. However, salinization is also frequent on irrigated grounds. If irrigation (which is fundamentally important in dry regions) is not done in a functional way, or with appropriate water, it can provoke an accumulation of salt (in particular chloride and sodium sulphate) that reduces the ability of plants to absorb nutritional elements from the roots, therefore making the soil sterile. The reclamation of saline soil is apparently a very simple process, as the salts can be removed with water. But before irrigating, it is necessary to increase the soil permeability, by increasing its porosity (pore number and dimension), in order to favour the passage of water and eliminate excessive salts. In nature some vegetal species tolerate salinity, as they are able to survive or produce (if they are very tolerant) even if there is an excessive quantity of salt in the soil.