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

Ans: (a)
Responsible Recycling (R2) Code of Practices is a set of guidelines for use by electronics recyclers to promote better environmental, health and security practices when recycling end-of-life electronics. Therefore, option (a) is the correct answer.

Ans: (b)

• The principal air pollutants emitted from the process is sulphur dioxide and particulate matter and the main portion of the solid waste is discarded slag. Hence, statement 3 is correct.
• The slag produced can contain significant concentrations of a number of potentially toxic elements including arsenic, lead, cadmium, barium, zinc, etc. The slag can release these potentially toxic elements into the environment under natural weathering conditions and cause pollution of soils, surface waters and groundwater. Hence, statement 2 is correct.
• Copper smelting does not release lethal quantities of carbon monoxide into the environment. Hence, statement 1 is not correct.

Therefore, option (b) is the correct answer.

Ans: (d)

• Furnace oil or fuel oil is a dark viscous residual product of crude-oil distillation. It is used as a fuel in different types of combustion equipment. The emissions of oxides of sulphur are a direct result of the sulphur content of the fuel oil. Hence, statements 1 and 3 are correct.
• Applications of Furnace oil
• Marine engines and slow speed engines for power generation; 
• Drying tea leaves;
• Thermic fluid heaters and hot air generators. Hence, statement 2 is correct. 

Therefore, option (d) is the correct answer.

Ans: (a)
Blue carbon is the carbon captured by the world’s ocean and coastal ecosystems. Coastal ecosystems such as mangroves, tidal marshes and seagrass meadows sequester and store more carbon per unit area than terrestrial forests and are now being recognised for their role in mitigating climate change. Therefore, option (a) is the correct answer.

Ans: (c)

• There are four particular types of habitats that ferns are found in: moist, shady forests; crevices in rock faces, especially when sheltered from the full sun; acid wetlands including bogs and swamps; and tropical trees, where many species are epiphytes. Hence, 1 is not correct.
• Lichens are generally found on substrates like rock, tree bark, soil, houses, tombstones, cars, old farm equipment, etc. Thus, lichen can be found surviving on surfaces without soil. Hence, 2 is correct.
• Mosses are non-vascular plants. They do not need soil to survive, instead they have a rhizoid multi-cell anchoring structure that is used to climb and grip over rocky surfaces. Moss thrives in moist and shady areas. Hence, 3 is correct.
• A mushroom is the fleshy, spore-bearing fruiting body of a fungus, typically grows above ground, on soil, etc. Hence, 4 is not correct.

Therefore, option (c) is the correct answer.

Ans: (b)

• Cyanobacteria, also called blue-green algae, are microscopic organisms found naturally in all freshwater ecosystems. These single-celled organisms use sunlight to make their own food. They are said to be the primary producer as they produce food for higher levels of organisms. Hence, 2 is correct.
• Diatoms are a major group of algae, specifically microalgae, found in the oceans, waterways and soils of the world. They are one of the major primary producers in the ocean, responsible annually for ~20% of photosynthetically fixed CO₂ on Earth. Hence, 3 is correct.

Ans: (d)

• Hedgehogs are small mammals with short limbs and a body low to the ground. Their most distinctive characteristic is the thousands of stiff, sharp spines — harder and sharper than those of a porcupine, that cover the animal’s back and sides. When attacked, they curl into a prickly and unappetizing ball that deters most predators. Hence, 1 is correct.
• A marmot is a rodent of medium size with brown fur on its head and back as well as yellow fur on its belly. This animal is a herbivore eating nuts, leaves, seeds, flowers, grass, and grains. Hence, 2 is not correct.
• Pangolins are the only mammals wholly-covered in scales and they use those scales to protect themselves from predators in the wild. If touched or grabbed, they roll up completely into a ball, while the sharp scales on the tail can be used to lash out. Hence, 3 is correct.

Therefore, option (d) is the correct answer.

Ans: (a)

• The New York Declaration on Forests is a voluntary and non-legally binding political declaration which grew out of dialogue among governments, companies and civil society, spurred by the United Nations Secretary-General’s Climate Summit in 2014. Hence, statement 1 is correct and statement 3 is not correct.
• The declaration pledges to halve the rate of deforestation by 2020, to end it by 2030 and to restore hundreds of millions of acres of degraded land. Hence, statement 2 is correct.
• The declaration currently has over 200 endorsers including, national governments, sub- national governments, multinational companies, indigenous peoples and local community organizations, non-government organizations, and financial institutions. Hence, statement 4 is correct.
• India was not one of the signatories at the time of New York Declaration on Forests inception. Hence, statement 5 is not correct.

Therefore, option (a) is the correct answer.

Ans: (d)

• The automotive industry uses ceramic or ferrite magnets to make vehicles safer. This kind of use of magnets in motor vehicles can generate magnetic particles. Hence, 1 is correct.
• Engines of motor vehicles can generate magnetic particles as they use high powered magnets which generate magnetic flux. Hence, 2 is correct.
• In Microwave, a magnetic stirrer is used which can generate magnetic particles. Hence, 3 is correct.
• Power plants release metal content along with ash. Use of coal in power plants is a major source of combustion-associated magnetite fine particles. Hence, 4 is correct. Telephone lines produce low frequency, low energy electromagnetic fields which are the potential source of magnetite particles. Hence, 5 is correct.

Therefore, option (d) is the correct answer.

Ans: (c)
Filter feeders are a subdivision of suspension-feeding entities which feed by straining suspended matter and food particles from water, by passing the water over a specialized filtering structure. Some animals that use this method of feeding are clams, krill, sponges, oysters, baleen whales, and many fish (including some sharks). Some birds, such as flamingos and certain species of duck, are also filter feeders. Therefore, option (c) is the correct answer.

Ans: (c)

• In nature, phosphorus is found mostly in the form of phosphate ions. Phosphate compounds are found in sedimentary rocks, and as the rocks weather down over long time periods, the phosphorus they contain slowly leaches into surface water and soils. 
• Volcanic ash, aerosols and mineral dust can also be significant phosphate sources. Phosphorus has no real gas phase, unlike other elements such as carbon, nitrogen and sulphur.

Therefore, option (c) is the correct answer.

Ans: (c)

• A detritivore is a heterotrophic organism, which obtains its nutrition by feeding on detritus. Detritus is an organic matter made up of dead plant and animal materials. 
• Detritivores are often invertebrate insects such as mites, beetles, butterflies and flies; molluscs such as slugs and snails; or soil-dwelling earthworms, millipedes and woodlice. Hence, 1, 3 and 5 are correct.
• Jellyfish are carnivorous and Seahorse is also a carnivorous animal. Hence, 2 and 4 are not correct.

Therefore, option (c) is the correct answer.

Ans: (a)
Common Carbon Metric allows emissions from buildings around the world to be consistently assessed and compared. It does not include value-based interpretation of the measurements such as weightings or benchmarking. Therefore, option (a) is the correct answer.

Ans: (d)
Symbiosis is a close ecological relationship between the individuals of two (or more) different species.

• The symbiotic association between the invertebrate phylum Cnidaria (Coelenterate) and the unicellular dinoflagellate algae, called zooxanthellae, is very common and symbolises mutualistic interaction. Hence, 1 is correct.
• Mycorrhizae are symbiotic relationships that are formed between fungi and plants. The fungi colonize the root system of a host plant, providing increased water and nutrient absorption capabilities while the plant provides the fungus with carbohydrates formed from photosynthesis. Hence, 2 is correct.
• Termites have a mutualistic relationship with protozoa that live in the insect’s gut. The termite benefits from the ability of bacterial symbionts within the protozoa to digest cellulose. The termite itself cannot do this, and without the protozoa, it would not be able to obtain energy from its food (cellulose from the wood it chews and eats). Hence, 3 is correct.

Therefore, option (d) is the correct answer.

Ans: (d)

• The Hyderabad city has been recognised as a ‘2020 Tree City of the World’ by the Arbor Day Foundation and the Food and Agriculture Organisation (FAO). Hence, statement 1 is not correct.
• Hyderabad is the only city in India to have been selected for this recognition in response to its commitment to growing and maintaining urban forestry through the Haritha Haram programme and Urban Forest Parks. Hence, statement 2 is correct. 

Therefore, option (d) is the correct answer.

Ans: (d)

• The Climate-Smart Village project in India is a CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS). The CCAFS started piloting the Climate-Smart Village in 2012 in Africa (Burkina Faso, Ghana, Mali, Niger, Senegal, Kenya, Ethiopia, Tanzania, and Uganda) and South Asia (Bangladesh, India, and Nepal). Hence, statement 1 is correct.
• Climate Change, Agriculture and Food Security (CCFAS) is carried out under CGIAR (formerly the Consultative Group for International Agricultural Research). The Headquarters of CGIAR is in Montpellier, France. CGIAR is a global partnership that unites international organizations engaged in research about food security. Hence, statement 2 is correct.
• International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) is a CGIAR Research Center. ICRISAT is a non-profit, non-political public international research organization that conducts agricultural research for development in Asia and sub- Saharan Africa with a wide array of partners throughout the world. Hence, statement 3 is correct.

Therefore, option (d) is the correct answer.