India has varied relief features, landforms, climatic realms and vegetation types. These have contributed in the development of various types of soils in India.  

• In ancient times, soils used to be classified into two main groups – Urvara and Usara, which were fertile and sterile, respectively. 
• Saline Soils are also known as Usara soils. Saline soils contain a larger proportion of sodium, potassium and magnesium, and thus, they are infertile, and do not support any vegetative growth.  

• They have more salts, largely because of dry climate and poor drainage. They occur in arid and semi-arid regions, and in waterlogged and swampy areas.  
• Their structure ranges from sandy to loamy. They lack in nitrogen and calcium. Saline soils are more widespread in western Gujarat, deltas of 
• The eastern coast and in Sunderban areas of West Bengal. In the Rann of Kuchchh, the Southwest Monsoon brings salt particles and deposits there as a crust. Seawater intrusions in the deltas promote the occurrence of saline soils. 

Source: NCERT XI – India Physical Environment