Soil Types of India — Set 10
Indian Agriculture · भारत की मृदा प्रकार · Questions 91–100 of 160
Which type of soil is best for growing rubber?
Correct Answer: C. Laterite soil
Laterite soil is best suited for growing rubber, especially in the humid tropical climate of Kerala and coastal Karnataka. Rubber trees (Hevea brasiliensis) tolerate the acidic conditions, free drainage, and warm, wet climate associated with Laterite soil regions. Kerala accounts for about 80% of India's rubber production, grown primarily on Laterite soils. The well-drained nature of Laterite soil prevents waterlogging around rubber tree roots.
Soil organic carbon (SOC) is important because:
Correct Answer: B. It improves soil structure, water holding capacity, nutrient availability, and supports soil biodiversity
Soil organic carbon (SOC) is crucial for soil health because it improves soil structure by binding particles into stable aggregates. Higher SOC increases water-holding capacity, reduces runoff, and improves nutrient availability. SOC is also a key energy source for soil microorganisms that drive nutrient cycling and disease suppression. India's soils generally have low SOC levels, and increasing it through organic matter addition is a key goal of soil health management.
Which soil type is found in the Western Ghats and is suitable for spice cultivation?
Correct Answer: C. Forest/Mountain soil and Laterite soil
Forest/Mountain soil and Laterite soil are found in the Western Ghats, where they support the cultivation of important spices like cardamom, pepper, ginger, and turmeric. The high rainfall, steep slopes, and dense forest cover of the Western Ghats create conditions ideal for forest soil formation with high organic matter. Kerala and Karnataka's spice gardens are established on these soils. The acidic nature of these soils suits acid-tolerant spice crops.
What is the main distinguishing feature between Khadar and Bangar alluvial soils?
Correct Answer: B. Khadar is newer, finer, and more fertile; Bangar is older, coarser, and less fertile
Khadar is the newer alluvial soil deposited in active flood plains that is renewed annually by floods, making it finer, more fertile, and lighter in colour. Bangar is older alluvial soil found at higher elevations away from flood plains, which is coarser, less fertile, and contains Kankar (lime nodules). Khadar is preferred for intensive agriculture due to its superior fertility. Bangar supports some agriculture but requires more inputs to achieve comparable yields.
Which of the following is NOT a method of soil conservation?
Correct Answer: B. Overgrazing
Overgrazing is a cause of soil degradation and erosion, not a method of soil conservation. Excessive grazing removes vegetation cover, compacts soil, and exposes it to water and wind erosion. Methods of soil conservation include contour ploughing, shelter belt planting, terracing, strip cropping, check dam construction, and afforestation. Preventing overgrazing and regulating livestock density are important conservation measures in grazing lands.
Which soil type is found in the Brahmaputra valley of Assam?
Correct Answer: C. Alluvial soil
The Brahmaputra valley of Assam is characterized by alluvial soil deposited by the Brahmaputra river and its numerous tributaries. This alluvial soil is highly fertile and supports the cultivation of rice, jute, tea, and mustard. The annual flooding of the Brahmaputra replenishes the soil with fresh alluvium, maintaining its fertility. The Brahmaputra valley alluvial soil is similar in nature to the alluvial soils of the Ganga plains.
The term 'bad land topography' is associated with which land degradation feature?
Correct Answer: C. Deeply gullied and ravine-affected land
'Bad land topography' refers to deeply gullied and ravine-affected land that has been severely eroded by water into a rugged, dissected landscape. The Chambal Valley in Madhya Pradesh and Rajasthan is the classic example of bad land topography in India. These lands are completely unsuitable for cultivation. Reclamation requires large-scale engineering works, afforestation, and check dam construction to stabilize the gullies.
What is the approximate area of India estimated to be affected by wind erosion?
Correct Answer: D. About 28 million hectares
Approximately 28 million hectares of India's land area is affected by wind erosion, primarily in the arid and semi-arid regions of Rajasthan, Gujarat, and Haryana. Wind erosion (aeolian erosion) removes the fine, nutrient-rich particles from the topsoil, leaving behind coarser, less fertile sand. Shelter belt planting and afforestation are the primary measures to combat wind erosion in these regions. The Thar Desert and its surroundings are the most wind-erosion-prone areas.
Which soil horizon contains the highest concentration of biological activity?
Correct Answer: D. A horizon
The A horizon (topsoil) contains the highest concentration of biological activity, including bacteria, fungi, earthworms, insects, and other soil organisms. This is because the A horizon has the highest organic matter content, which provides food and energy for soil organisms. The biological activity in the A horizon drives nutrient cycling, organic matter decomposition, and soil structure formation. Protecting the A horizon from erosion is critical for maintaining soil fertility.
Which river system is responsible for depositing the alluvial soil in the Ganga plains?
Correct Answer: C. Ganga, Yamuna, and their Himalayan tributaries
The alluvial soil of the Ganga plains is deposited by the Ganga, Yamuna, and their numerous Himalayan tributaries including the Ghaghra, Gandak, Kosi, and Yamuna. These rivers originate in the Himalayas and carry large amounts of eroded rock material (sediment) that is deposited as they slow down in the flat plains. Over millions of years, these deposits have built up a deep layer of fertile alluvial soil. The Ganga plains are among the most fertile agricultural regions in the world.