Indian Soil Types Practice Questions

Correct answer: Alluvial Soil

Alluvial soil is the most widespread soil type in India, primarily found in the Indo-Gangetic plains and river deltas. It is highly fertile and supports a large variety of crops like wheat, rice, and sugarcane.

Correct answer: Cotton

Black soil is ideal for cotton cultivation due to its high water-retention capacity and clayey texture. It is predominantly found in the Deccan Trap region, including Maharashtra and Gujarat.

Correct answer: Iron Oxide

Red soil develops on crystalline igneous rocks and owes its distinct color to the wide diffusion of iron in crystalline and metamorphic rocks. When it occurs in a hydrated form, it may appear yellow.

Correct answer: Laterite Soil

Laterite soil is formed under conditions of high temperature and heavy rainfall with alternating wet and dry periods. This process causes nutrients to be washed away, leaving the soil rich in iron and aluminum oxides.

Correct answer: Desert Soil

Arid soils are sandy in texture and saline in nature. They have a low humus and moisture content, but with proper irrigation, they can become productive for crops like bajra and pulses.

Correct answer: Bhangar

Bhangar represents the older alluvium that contains calcareous deposits known as 'kankar'. It is less fertile than the Khadar (newer alluvium) and is found above the floodplains of rivers.

Correct answer: Laterite Soil

Red laterite soils in Tamil Nadu, Andhra Pradesh, and Kerala are highly suitable for tree crops like cashews and rubber. These soils are generally poor in organic matter but respond well to fertilizers.

Correct answer: Organic Matter

Peaty soils are characterized by a high content of organic matter (sometimes up to 40-50%). They are usually heavy, black in color, and acidic, found in parts of Bihar, Uttaranchal, and coastal Kerala.

Correct answer: Saline Soil

Saline soils (Usara) contain a high proportion of sodium, potassium, and magnesium. They are infertile and do not support much vegetation, occurring mostly in arid and semi-arid regions and coastal inlets.

Correct answer: Snow-bound areas

In the snow-bound areas of the Himalayas, forest soils undergo denudation and are acidic with low humus content. In contrast, soils in the lower river valleys are fertile and loamy.

Correct answer: Black Soil

Black soil develops deep cracks during the dry season, which allows for oxygenation of the soil. This process of the soil falling into the cracks is termed 'self-ploughing'.

Correct answer: Khadar

Khadar is the light-colored, fine-grained newer alluvium found in the floodplains. Because it is replenished annually by river floods, it remains highly fertile for intensive agriculture.

Correct answer: Laterite Soil

Laterite soils are found in regions with high rainfall and temperature, such as the summits of the Western Ghats and the hills of Assam. They are typically acidic and low in nitrogen and phosphate.

Correct answer: Nitrogen, Phosphorus, Humus

Most Indian soils, including alluvial and black soils, are typically poor in nitrogen, phosphorus, and organic matter (humus). Potassium is usually present in sufficient quantities in most types.

Correct answer: Peaty Soil

Kari soil is a type of peaty, black, and highly acidic soil found in Kerala. It is rich in organic matter but requires specific management for rice cultivation due to its acidity.

Correct answer: The Deccan Plateau

Red and yellow soils are found in areas of low rainfall in the eastern and southern parts of the Deccan Plateau. They also occur in parts of Odisha, Chhattisgarh, and the southern part of the Middle Ganga plain.

Correct answer: Over-irrigation

In areas of intensive irrigation, the water table rises, bringing salts to the surface through capillary action. This leads to the deposition of salt (salinity/alkalinity), locally known as 'Reh' or 'Kallar'.

Correct answer: Alluvial Soil

Alluvial soils are depositional soils. The three main river systems—the Indus, the Ganga, and the Brahmaputra—have deposited this silt over millions of years to form the great plains.

Correct answer: Loamy and Silty

In mountain regions, soil texture varies according to altitude and environment. While they can be coarse-grained on the upper slopes, they are usually loamy and silty in the fertile valley floors.

Correct answer: Laterite and Forest Soil

Forest soils (mountain soils) and laterite soils found on hill slopes are preferred for tea, coffee, and spice plantations. They require well-drained conditions which the sloping terrain provide naturally.