Identify the type of soil on the basis of given characteristics: 1. They contain a large proportion of sodium, potassium and magnesium, and thus, they are infertile. 2. Their texture ranges from sandy to loamy. 3. They are more widespread in western Gujarat, deltas of the eastern coast and in Sunderban areas of West Bengal.

The characteristics described identify Saline soils. These soils contain a high proportion of sodium, potassium, and magnesium, making them infertile. They are often referred to as 'Usar' or 'Reh' and are characterized by a white salt crust formed through capillary action [3]. Texturally, saline soils range from sandy to loamy [1]. Geographically, they are widespread in western Gujarat (Rann of Kutch), the deltas of the eastern coast (Mahanadi, Krishna, Kaveri), and the Sunderban areas of West Bengal. While arid soils are also saline and sandy, they are specifically noted for Kankar layers and are primarily found in Rajasthan [2]. Peaty soils are rich in organic matter and found in heavy rainfall areas, whereas saline soils develop in areas with high evaporation or sea water ingression [4].

Sources

1. [1] Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 6: Soils > 11. Saline and Alkaline Soils > p. 13
2. [3] Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 6: Soils > Table 6.1 > p. 9
3. [2] Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 6: Soils > iv) Saline and Alkaline Soils > p. 19
4. [4] NCERT. (2022). Contemporary India II: Textbook in Geography for Class X (Revised ed.). NCERT. > Chapter 1: The Rise of Nationalism in Europe > Arid Soils > p. 11