UPSC CSE Prelims
Indian Geography Previous Year Questions (PYQs)

Detailed Explanation:

Answer: Option 2 — 2 and 4

Among the given rivers, only Nagavali and Vamsadhara originate from the Eastern Ghats, while Brahmani and Subarnarekha have their sources in the Chota Nagpur Plateau of Jharkhand.

❌ Statement 1 – Incorrect: The Brahmani river is formed by the confluence of Sankh and South Koel rivers near Rourkela; these headstreams originate in the Chota Nagpur Plateau of Jharkhand, not the Eastern Ghats.

✅ Statement 2 – Correct: The Nagavali river (also known as Langulya) originates in the Eastern Ghats near Lakhbahal in the Kalahandi district of Odisha.

❌ Statement 3 – Incorrect: The Subarnarekha river originates in the Chota Nagpur Plateau near Ranchi in Jharkhand and flows through West Bengal and Odisha before entering the Bay of Bengal.

✅ Statement 4 – Correct: The Vamsadhara river originates in the Eastern Ghats near Lanjigarh in the Kalahandi district of Odisha and flows through Andhra Pradesh before joining the Bay of Bengal.

📝 Short Notes: Rivers Originating from Eastern Ghats

• Eastern Ghats: A discontinuous range of mountains running parallel to the eastern coast of India through Odisha, Andhra Pradesh, Telangana, and Tamil Nadu.
• Major Rivers from Eastern Ghats: Mahanadi, Godavari (tributaries), Krishna (tributaries), Penner, Palar, Vaigai, Nagavali, Vamsadhara, and several smaller coastal rivers.
• Nagavali River: Originates in Kalahandi district (Odisha), flows through Odisha and Andhra Pradesh, length ~256 km, enters Bay of Bengal near Kalingapatnam.
• Vamsadhara River: Originates in Kalahandi district (Odisha) near Lanjigarh, flows through Odisha and Andhra Pradesh, length ~254 km, meets Bay of Bengal near Kalingapatnam.
• Chota Nagpur Plateau Rivers: Brahmani, Subarnarekha, Damodar, and other rivers originate from this plateau in Jharkhand, not from the Eastern Ghats.
• Coastal Drainage: Rivers from Eastern Ghats typically have shorter courses and form smaller drainage basins compared to peninsular rivers originating from the Western Ghats.

Detailed Explanation:

Answer: Option 4 — Sutlej

The Sutlej is the river that joins the Indus directly after receiving the collective drainage of the other three rivers. The Jhelum and Ravi rivers merge with the Chenab, and the Chenab subsequently joins the Sutlej in Pakistan. The Sutlej then flows into the Indus a few kilometres above Mithankot, making it the final conduit for the combined waters before their confluence with the Indus.

📝 Short Notes: Indus River System

• Five Major Tributaries: The Indus river system comprises five major tributaries known as the Panjnad (five rivers): Jhelum, Chenab, Ravi, Beas, and Sutlej.
• Confluence Pattern: Jhelum joins Chenab near Jhang in Pakistan; Ravi joins Chenab near Sidhnai; Beas joins Sutlej at Harike in Punjab, India; Chenab joins Sutlej near Panjnad in Pakistan.
• Final Confluence: The Sutlej (carrying waters of all other tributaries) joins the Indus directly near Mithankot in Pakistan.
• Origin: All five rivers originate in the Himalayas; Sutlej originates from Rakas Lake near Mansarovar in Tibet.
• Geographical Significance: The Indus system drains parts of India, Pakistan, China, and Afghanistan, making it one of the longest rivers in Asia (approximately 3,180 km).

Detailed Explanation:

Answer: Option 4 — Saline lakes

Didwana, Kuchaman, Sargol, and Khatu are saline lakes located in Rajasthan, India. These salt lakes are significant for salt production and are characteristic of the arid and semi-arid regions of Rajasthan where high evaporation rates lead to salt concentration in water bodies.

📝 Short Notes: Saline Lakes of Rajasthan

• Sambhar Lake: The largest saline lake in India, located in Rajasthan between Jaipur and Ajmer; a Ramsar site and major source of salt production.
• Didwana Lake: Located in Nagaur district; known for high salt concentration and commercial salt extraction.
• Kuchaman Lake: Saline lake in Nagaur district; supports salt industry and seasonal water body.
• Pachpadra Lake: Another important saline lake in Barmer district known for salt production.
• Formation: These lakes are formed in inland drainage basins where high evaporation exceeds precipitation, leading to salt accumulation.
• Economic Significance: These lakes contribute significantly to India's salt production, supporting local economy and employment.

Detailed Explanation:

Answer: Option 2 — fissure volcanic rock

Black cotton soil (also known as Regur soil) in India is primarily formed by the weathering of basaltic lava flows from fissure volcanic eruptions. These soils are predominantly found in the Deccan Plateau region, covering parts of Maharashtra, Gujarat, Madhya Pradesh, and Karnataka, where the parent material is basaltic rock. The dark color comes from the presence of titaniferous magnetite and aluminum-rich minerals, while the high clay content gives it swelling and shrinking properties.

📝 Short Notes: Black Cotton Soil (Regur Soil)

• Parent Material: Formed from weathering of basaltic lava (Deccan Trap volcanic rocks)
• Geographical Distribution: Deccan Plateau, Malwa Plateau - mainly in Maharashtra, Gujarat, Madhya Pradesh, Karnataka, parts of Andhra Pradesh and Tamil Nadu
• Physical Properties: Deep black to dark gray color; rich in clay, lime, iron, magnesium, and aluminum but deficient in nitrogen, phosphorus, and organic matter
• Characteristic Feature: High clay content causes swelling when wet and shrinking when dry, developing deep cracks in summer
• Moisture Retention: Excellent moisture retention capacity due to high clay content, suitable for dry farming
• Major Crops: Ideal for cotton cultivation; also suitable for sugarcane, jowar, wheat, linseed, and citrus fruits
• Other Names: Regur soil, Black soil, or Tropical Black Earth

Detailed Explanation:

Answer: Option 4 — 2 and 3

The 'Right to the City' is a normative concept advocating inclusive urban citizenship, not a formally recognized universal human right with binding UN monitoring. Statement 1 is incorrect as UN-Habitat promotes this concept through the New Urban Agenda but does not monitor legally binding commitments. Statements 2 and 3 correctly capture the essence of this concept.

❌ Statement 1 – Incorrect: 'Right to the City' is not an agreed universal human right; UN-Habitat does not monitor binding national commitments in this regard.

✅ Statement 2 – Correct: This concept gives all inhabitants the right to reclaim public spaces, participate in governance, and shape their cities democratically.

✅ Statement 3 – Correct: The concept promotes inclusive urban citizenship, meaning basic services cannot be denied even to unauthorized colonies; Indian courts have upheld this under Article 21 (Right to Life).

📝 Short Notes: Right to the City

• Origin: Concept developed by French philosopher Henri Lefebvre (1968); popularized in urban planning discourse.
• Definition: Right of all inhabitants to use, occupy, govern, and enjoy cities that are just, inclusive, safe, and sustainable.
• Key Principles: Inclusive citizenship, non-discrimination, social function of land, democratic participation in urban governance.
• UN-Habitat & New Urban Agenda (2016): Promotes the concept but it remains aspirational, not legally binding.
• Indian Context: Courts have held that basic services (water, sanitation) cannot be denied to slum/unauthorized dwellers under Article 21.
• Beneficiaries: Migrants, slum dwellers, informal workers, residents of unauthorized settlements—all recognized as rights-bearing urban citizens.

Detailed Explanation:

Answer: Option 2 — 2 and 3 only

This question tests knowledge about groundwater management in India and the role of the Central Ground Water Authority (CGWA). Statement 1 provides incorrect figures about overexploited/critical districts, while Statements 2 and 3 are factually accurate regarding CGWA's formation and India's groundwater irrigation status.

❌ Statement 1 – Incorrect: According to the National Compilation on Dynamic Groundwater Resources of India, 2017, only 17% of assessment units are overexploited and 5% are critical, totaling 22% (not 36% of districts).

✅ Statement 2 – Correct: The Central Ground Water Authority (CGWA) was indeed established in 1997 under Section 3(3) of the Environment (Protection) Act, 1986 to regulate and control groundwater development and management.

✅ Statement 3 – Correct: India has the world's largest area under groundwater irrigation, accounting for approximately 60% of its irrigated agriculture, due to extensive bore-well and tube-well usage.

📝 Short Notes: Central Ground Water Authority (CGWA)

• Establishment: Constituted in 1997 under Section 3(3) of the Environment (Protection) Act, 1986
• Parent Ministry: Ministry of Jal Shakti (Department of Water Resources)
• Primary Function: Regulation and control of groundwater development and management across India
• Classification Categories: Assessment units are classified as Safe, Semi-Critical (70-90% extraction), Critical (90-100% extraction), and Over-Exploited (>100% extraction)
• Groundwater Status (2017 Report): Out of 6,881 assessment units - 17% Over-Exploited, 5% Critical, 14% Semi-Critical, and 64% Safe
• India's Irrigation: India has the largest groundwater irrigation area globally, with groundwater contributing to about 60% of irrigated agriculture
• Powers: CGWA can issue directives for regulation of groundwater extraction in notified areas and impose restrictions on groundwater development

Detailed Explanation:

Answer: Option 4 — North of Nubra Valley

The Siachen Glacier is located in the eastern Karakoram range of the Himalayas, positioned north of the Nubra Valley in Ladakh. It is the world's highest battlefield, where India maintains a military presence at altitudes exceeding 5,400 meters.

✅ Option 4 – Correct: Siachen Glacier lies directly north of Nubra Valley in the eastern Karakoram range.
❌ Option 1 – Incorrect: Aksai Chin is located to the east of Ladakh, whereas Siachen is to the northwest of it.
❌ Option 2 – Incorrect: Leh is situated to the south of Siachen Glacier, not to its west.
❌ Option 3 – Incorrect: Gilgit is in the Gilgit-Baltistan region, west of Siachen Glacier, not to its south.

📝 Short Notes: Siachen Glacier and Surrounding Geography

Detailed Explanation:

Answer: Option 3 — 3-2-4-1

The question asks for the ascending order (lowest to highest) of forest cover as a percentage of total geographical area. According to the India State of Forest Report (ISFR) 2021, Maharashtra has the lowest percentage at 16.51%, followed by Madhya Pradesh at 25.14%, Odisha at 33.50%, and Chhattisgarh has the highest at 41.21%. Therefore, the correct ascending order is 3 (Maharashtra) - 2 (Madhya Pradesh) - 4 (Odisha) - 1 (Chhattisgarh).

📝 Short Notes: Forest Cover in Indian States

Detailed Explanation:

Answer: Option 4 — Water reservoirs

The common feature among Aliyar, Isapur, and Kangsabati is that they are all locations of significant water reservoirs in India. Aliyar Reservoir is located in Tamil Nadu, Isapur Dam is an irrigation project in Maharashtra, and Kangsabati Dam is situated on the Kangsabati River in West Bengal. All three serve as important water storage and irrigation infrastructure.

📝 Short Notes: Major Reservoirs in India

• Aliyar Reservoir: Located in Aliyar village, Pollachi taluk, Coimbatore district, Tamil Nadu. Created by the Aliyar Dam on the Aliyar River.
• Isapur Dam: An irrigation project located in Maharashtra, designed to support agricultural activities in the region.
• Kangsabati Reservoir: Located in West Bengal, created by the Kangsabati Dam (also known as Kumari Dam) on the Kangsabati River, primarily for irrigation and drinking water supply.
• Purpose: These reservoirs serve multiple purposes including irrigation, drinking water supply, flood control, and sometimes hydroelectric power generation.
• Importance: Such water infrastructure is critical for agricultural productivity, water security, and regional development in India.

Detailed Explanation:

Answer: Option 1 — 1, 2 and 4

This question tests knowledge of major Himalayan glaciers and their associated river systems. The correctly matched pairs are Bandarpunch-Yamuna, Bara Shigri-Chenab, and Siachen-Nubra, making option 1 the correct answer.

✅ Pair 1 – Bandarpunch : Yamuna – Correct: Bandarpunch glacier in the Garhwal Himalayas of Uttarakhand is one of the principal sources of the Yamuna River.

✅ Pair 2 – Bara Shigri : Chenab – Correct: Bara Shigri is the second-longest glacier in the Himalayas (after Gangotri) and feeds the Chenab River through its tributary system.

❌ Pair 3 – Milam : Mandakini – Incorrect: Milam Glacier in Uttarakhand feeds the Gori Ganga River (tributary of Kali River), not Mandakini. Mandakini originates from Chorabari Glacier near Kedarnath.

✅ Pair 4 – Siachen : Nubra – Correct: Siachen Glacier in the Karakoram Range is one of the world's longest mountain glaciers and is the source of the Nubra River, which later joins the Shyok River.

❌ Pair 5 – Zemu : Manas – Incorrect: Zemu Glacier in Sikkim feeds the Teesta River, not the Manas River. Manas originates in Bhutan and flows through Assam.

📝 Short Notes: Major Himalayan Glaciers and Their Rivers

Detailed Explanation:

Answer: Option 1 — 1 and 2 only

This question tests the knowledge of famous places in India and the rivers associated with them. Out of the three pairs given, only pairs 1 and 2 are correctly matched.

✅ Pair 1 – Correct: Pandharpur is a renowned pilgrimage town located on the banks of the Chandrabhaga River (also known as Bhima River) in Solapur district, Maharashtra.

✅ Pair 2 – Correct: Tiruchirappalli (Trichy) is situated along the banks of the Cauvery River in Tamil Nadu, which is one of the major rivers of South India.

❌ Pair 3 – Incorrect: Hampi, a UNESCO World Heritage Site in Karnataka, is located on the banks of the Tungabhadra River, not the Malaprabha River.

📝 Short Notes: Important Rivers and Associated Cities in India

• Chandrabhaga River: Also known as Bhima River; Pandharpur (Maharashtra) is located on its banks; it is a tributary of Krishna River.
• Cauvery River: Major river of South India; flows through Karnataka and Tamil Nadu; important cities include Tiruchirappalli, Srirangapatna, and Thanjavur.
• Tungabhadra River: Formed by confluence of Tunga and Bhadra rivers; flows through Karnataka and Andhra Pradesh; Hampi is located on its banks.
• Malaprabha River: A tributary of Krishna River; flows through Karnataka; does not pass through Hampi.
• Krishna River: One of the longest rivers in India; flows through Maharashtra, Karnataka, Telangana, and Andhra Pradesh; receives tributaries like Bhima (Chandrabhaga) and Tungabhadra.

Detailed Explanation:

Answer: Option 4 — The level of mutual trust and harmony in the society

Social capital refers to the networks, norms, and trust that enable participants to act together more effectively to pursue shared objectives. It is an intangible asset that measures the quality of social relationships, mutual trust, and cooperation within a community or society.

❌ Option 1 – Incorrect: The proportion of literates represents human capital (individual skills and knowledge), not social capital which focuses on collective relationships and trust.

❌ Option 2 – Incorrect: The stock of buildings, infrastructure, and machines constitutes physical capital, which refers to tangible assets used in production.

❌ Option 3 – Incorrect: The size of the working-age population is a demographic indicator and represents potential human capital, but does not reflect social connections or trust.

✅ Option 4 – Correct: The level of mutual trust and harmony directly captures the essence of social capital, which emphasizes the quality of social bonds, civic engagement, and cooperative relationships in society.

📝 Short Notes: Forms of Capital

Detailed Explanation:

Answer: Option 2 — 3 only

Among the three statements about agricultural soils, only statement 3 is correct. Statement 1 incorrectly claims that organic matter reduces water-holding capacity, when it actually increases it. Statement 2 incorrectly suggests soil plays no role in the sulphur cycle, when in fact soil is crucial for sulphur transformations and storage.

❌ Statement 1 – Incorrect: High organic matter content actually increases water-holding capacity of soil, not reduces it. Organic matter acts like a sponge, creating pore spaces that retain moisture effectively.

❌ Statement 2 – Incorrect: Soil plays a vital role in the sulphur cycle through microbial transformations (mineralization, immobilization) and storage of sulphur compounds like sulfates that are essential plant nutrients.

✅ Statement 3 – Correct: Prolonged irrigation, especially with poor drainage and high-salt water, causes accumulation of salts in the soil profile, leading to salinization that adversely affects crop productivity.

📝 Short Notes: Soil Properties and Agricultural Impacts

• Organic Matter Benefits: Increases water retention, improves soil structure, enhances nutrient availability, promotes microbial activity, and increases cation exchange capacity (CEC).
• Soil in Nutrient Cycles: Soil is integral to carbon, nitrogen, phosphorus, and sulphur cycles through microbial decomposition, mineralization, and nutrient transformation processes.
• Salinization Process: Occurs when irrigation water brings dissolved salts that accumulate in root zones due to evaporation and inadequate drainage, particularly in arid and semi-arid regions.
• Prevention of Salinization: Proper drainage systems, use of quality irrigation water, crop rotation with salt-tolerant species, and leaching of accumulated salts.
• Indicators of Salinization: White salt crusts on soil surface, reduced crop growth, increased soil pH, and presence of salt-tolerant weeds.

Detailed Explanation:

Answer: Option 1 — Kodaikanal Tamil Nadu

Kodaikanal Lake, also known as Kodai Lake, is a man-made lake located in Kodaikanal city in Dindigul district, Tamil Nadu. It was created in 1863 by Sir Vere Henry Levinge, the then Collector of Madurai, and is a popular tourist attraction. The other three lakes mentioned—Kolleru (Andhra Pradesh), Nainital (Uttarakhand), and Renuka (Himachal Pradesh)—are all natural lakes.

📝 Short Notes: Important Artificial and Natural Lakes of India

Detailed Explanation:

Answer: Option 4 — 1 only

Only Statement 1 is correct. Barren Island is indeed India's only active volcano, located in the Andaman Sea within Indian territory. Statement 2 is incorrect because Barren Island lies approximately 135-140 km east of Port Blair, not Great Nicobar, which is much further south. Statement 3 is also incorrect as the volcano has erupted multiple times after 1991, including in 1994-95, 2005-07, and most recently in 2017, proving it has not remained inactive.

✅ Statement 1 – Correct: Barren Island is the only confirmed active volcano in India, located in the Andaman Sea, part of the Union Territory of Andaman and Nicobar Islands.
❌ Statement 2 – Incorrect: Barren Island is located approximately 135-140 km east of Port Blair, not Great Nicobar; Great Nicobar is the southernmost island located much further south (around 7°N) while Barren Island is at approximately 12.2°N.
❌ Statement 3 – Incorrect: The volcano has not remained inactive since 1991; it has erupted several times including in 1994-95, 2005-07, and as recently as 2017.

📝 Short Notes: Barren Island Volcano

• Location: Barren Island is located in the Andaman Sea, approximately 135-140 km east of Port Blair in the Andaman and Nicobar Islands.
• Only Active Volcano: It is the only confirmed active volcano in South Asia and India.
• Part of Volcanic Arc: Barren Island is part of the volcanic arc chain extending from Sumatra to Myanmar, formed due to the subduction of the Indian Plate beneath the Burmese Plate.
• Eruption History: After lying dormant for nearly 150 years, it erupted in 1991, and has since shown activity in 1994-95, 2005-07, and 2017.
• Uninhabited: The island is uninhabited due to volcanic activity and is restricted for tourism, though diving expeditions are sometimes permitted.
• Geographical Coordinates: Approximately 12.2°N latitude and 93.9°E longitude.