There are many different salts in soil that provide nutrients to plants. However, if there is too much salt in the soil, this interferes with water uptake. Salty or saline soils can result from various sources of salt ions.
When a soil contains excess of sodium salts and clay complex still contains exchangeable calcium, the soil is known as Saline soil. Saline soils are salty in nature with PH value of less than 7 in PH scale.
This soil has a poor soil structure and a low infiltration capacity. The saline soil is also known as white alkali or brown alkali soil.
Soil Salinity is the salt content in the soil. The process of increasing the salt content is known as Salinization. Salts occur naturally within soils and water.
Salinization can be caused by natural processes such as mineral weathering or by the gradual withdrawal of an ocean.
Saline soil contains sufficient neutral soluble salts to adversely affect the growth of most crop plants.
Saline soils exist in arid and semi arid regions and in regions of poor natural drainage. Salinity in dry lands can occur when the water table is between two and three meters from the surface of the soil.
Alkali, or Alkaline soils are clay soils with high PH value of greater than 7 in PH scale. This soil has a poor soil structure and a low infiltration capacity. Often they have a hard Calcareous layer at 0.5 to 1 metre depth.
Alkaline soils is often called as ‘black alkali’ soils, because they are black, owing to the effect of the high sodium content which causes the dispersion of the organic matter.
Alkaline soils contains a great amount of Sodium, Calcium and Magnesium. Because alkaline soil is less soluble than acidic or neutral soil, availability of nutrients is often limited.
In arid or desert areas where rainfall is slim and places where there are dense forests, soil tends to be more alkaline. Soils can also become more alkaline if it is watered with hard water that contains lime.
Alkaline soils are difficult to take into agricultural production. Due to the low infiltration capacity, rain water stagnates on the soil easily and, in dry periods, cultivation is hardly possible without copious irrigated water and good drainage.
|Saline Soils||Alkaline Soils|
|Have high salt content||Have high Sodium content|
|PH value lesser than 7||PH value greater than 7|
|Also called White or Brown alkali soil||Also called as Black alkali soil|