UPSC Prelims Previous Year Questions 2021: Geography | Geography for UPSC CSE PDF Download

Ans: (c)

• The forest development in such areas is kept in check due to certain conditions including:
• Fire: Uncontrolled burning of grassland leads to wildfires. Hence, 2 is correct. Grazing Herbivores: Overgrazing by animals leads to desertification and removal of vegetation cover. Hence, 3 is correct.
• Seasonal Rainfall: Savanna regions have two distinct seasons - a wet season and a dry season. There is very little rain in the dry season. In the wet season vegetation grows, including lush green grasses and wooded areas. Hence, 4 is correct.

Therefore, option (c) is the correct answer.

Ans: (b)

• There is more freshwater stored in the ground than rivers, lakes, ponds on the surface. Some of the water flowing in rivers also comes from seepage of groundwater into river beds. Water from precipitation continually seeps into the ground to recharge aquifers. Hence, statement 1 is not correct.
• Of total freshwater, over 68 percent is locked up in ice and glaciers mainly in the polar regions and Greenland. Another 30 percent of freshwater is in the ground. Hence, statement 2 is correct.

Therefore, option (b) is the correct answer.

Ans: (b)

• Moringa (Moringa oleifera), also known as drumstick tree, belongs to the family Moringaceae and is a handsome softwood tree, native to India, occurring wild in the sub-Himalayan regions of Northern India and now grown world wide in the tropics and sub-tropics. The pod of moringa is a very popular vegetable in South Indian cuisine and valued for their distinctly inviting flavour. Hence, statement 1 is not correct.
• Tamarind (Tamarindus indica) is a hardwood tree. It is native to Africa but also grows in India, Pakistan, and many other tropical regions. Hence, statement 2 is not correct. Moreover, in India most of the Tamarind is collected as Minor Forest Produce with Minimum Support Price. Tamarind is also actively exported from India. Hence, statements 3 and 4 are correct.
• Biodiesel is derived from the tamarind seed through the transesterification process as potential alternative feedstock for the diesel engine. Hence, statement 5 is correct. Therefore, option (b) is the correct answer.

Ans: (b)
Black soil, also known as regur soil or black cotton soil, is ideal for growing cotton. Black soil is typical of the Deccan trap (Basalt) region spread over northwest Deccan plateau and is made up of lava flows (fissure volcanic rock). Therefore, option (b) is the correct answer.

Ans: (b)

• Permaculture is a totally integrated design system that is modelled on nature. Permaculture farming promotes multi cropping and integrated farming systems, whereas chemical farming is more suitable for monoculture cropping due to use of crop specific inputs like irrigation, chemical fertiliser and harvesting methods. Hence, 1 is correct.
• Chemical farming makes the soil less fertile over time due to use of chemical fertilizers, which can lead to serious problems like soil salinisation. But such problems do not occur in permaculture farming as it relies on organic fertilizers. Hence, 2 is correct.
• The concept of permaculture involves well-designed systems that do not produce waste and tries to copy well-designed systems. Permaculture tries to take into account local conditions like arid climate, which helps in developing a suitable system to ensure sustainable production. In case of chemical farming, intense use of chemical fertilizers and irrigation make the soil less fertile over time, thus restricting its practice in semi- arid regions. Thus, conventional chemical farming is not suitable for semi-arid regions. Hence, 3 is not correct.
• Mulching is a long-established horticultural practice that involves spreading a layer of material on the ground around plants to protect their roots from heat, cold, or drought or to keep the fruit clean.The material used for covering is called ‘mulch’. Mulching is usually practiced while cultivating commercially important crops, fruit trees, vegetables, flowers, nursery saplings, etc. Mulching is an important component of permaculture farming for promoting maximum efficiency. Whereas, conventional chemical farming does not consider it as essential. Hence, 4 is correct.

Therefore, option (b) is the correct answer.

Ans: (b)

• Palm oil is edible vegetable oil that comes from the fruit of oil palm trees. Oil palm trees are native to Africa but were brought to South-East Asia over 100 years ago as an ornamental tree crop. The tree grows best in tropical climates with abundant water. Hence, statement 1 is not correct.
• Palm oil is used in cosmetics products like lipstick and perfumes. It is one of the most cost-effective cosmetics ingredients. Due to its high fatty acid content, it can be used to make surfactants, emulsifiers and emollients. Hence, statement 2 is correct.
• Palm oil can be used to produce biodiesel, which can be used in compression ignition engines, i.e., diesel engines without any modifications. Hence, statement 3 is correct. Therefore, option (b) is the correct answer.

Ans: (d)

• The Jhelum joins the Chenab near Jhang in Pakistan. The Ravi joins the Chenab near Sarai Sidhu.
• Satluj is joined by the Chenab in Pakistan. Thus, Satluj receives the collective drainage of the Ravi, Chenab and Jhelum rivers. It joins the Indus a few kilometres above Mithankot. Therefore, option (d) is the correct answer.

Ans: (d)
A salt lake or saline lake is a landlocked body of water that has a concentration of salts and other dissolved minerals significantly higher than most lakes. Didwana, Kuchaman, Sargol and Khatu are saline lakes of Rajasthan. Therefore, option (d) is the correct answer.

Ans: (b)

1. The Brahmani river, also known as South Koel, rises near Nagri village in Ranchi district of Jharkhand. Hence, 1 is not correct.
2. The Nagavali river originates in the Eastern Ghats near Lakhbahal, located in the Kalahandi district of Odisha. Langulya is another name for Nagavali River. Hence, 2 is correct.
3. Subarnarekha river originates in the Chota Nagpur Plateau near Nagri village in Ranchi district of Jharkhand. Hence, 3 is not correct.
4. Vamsadhara river rises in the Eastern Ghats of Orissa and enters Srikakulam district in Bhamini Mandal and finally falls into the Bay of Bengal near Kalingapatnam. Hence, 4 is correct.

Therefore, option (b) is the correct answer.

Ans: (a)

Sugarcane is an important cash crop cultivated in India. It is the least water efficient crop. The water requirement for sugarcane is 1800-2200 mm/season. Therefore, option (a) is the correct answer.

Ans: (c)

• Warmer water is transported westward in the ocean by the Northeast trade winds in the Northern hemisphere of the tropical zone. So, in tropical zones, the western section of ocean is warmer than eastern sections due to trade winds. Hence, statement 1 is correct.
• The Westerlies play an important role in carrying the warm, equatorial waters and winds to the western coasts of continents (that is eastern section of the Oceans in the temperate zone). Thus, in temperate zones, westerlies make the eastern section of the ocean warmer than the western sections. Hence, statement 2 is correct.

Therefore, option (c) is the correct answer.

Ans: (d)

In tropical rainforest biomes, hot, moist atmosphere and all the dead plant material create the perfect conditions in which bacteria and other microorganisms can thrive. This leads to rapid decomposition of leaf litter material. Therefore, option (d) is the correct answer.