India - Soils

200 cms

Step 1: Laterite soil forms in areas receiving more than 200 cms of annual rainfall. Step 2: Heavy rainfall washes away silicate and minerals from the soil. Step 3: This leaves behind ferric oxide and aluminium in the surface soil. Step 4: The high rainfall is essential for the leaching process that creates laterite soil, making 200 cms the minimum threshold mentioned in the chapter.

Mountain soil

Step 1: Mountain soil is rich in nitrogen and organic matter from decayed plants and animals. Step 2: It is found on lower slopes of mountains with good drainage and climate. Step 3: These conditions are perfect for plantation crops like tea, coffee, and spices. Step 4: Alluvial soil is for cereals, black soil for cotton, and desert soil has very limited crop options, making mountain soil the best choice for tea and coffee.

Deccan Trap

Step 1: The area covered by black soil is geologically known as the Deccan Trap. Step 2: This region was formed by volcanic activity, creating igneous rocks. Step 3: Black soil is formed from weathering of these igneous rocks. Step 4: Indo-Gangetic Plain has alluvial soil, Thar Desert has desert soil, and Western Ghats have laterite soil, making Deccan Trap the correct answer.

Rajasthan

Step 1: Desert soil is mainly distributed in North-west Rajasthan. Step 2: This region has low rainfall and high temperatures, perfect conditions for desert soil formation. Step 3: The soil is also found in adjoining areas of Punjab, Haryana, and western Gujarat. Step 4: Kerala has laterite soil, West Bengal has alluvial soil, and Odisha has alluvial and red soil, making Rajasthan the correct answer for desert soil.