UPSC 2021 Environment and Ecology Questions with Answers

Explanation

Copper Smelting is a process of applying heat to ore in order to extract a base metal. Smelting uses heat and a chemical reducing agent to decompose the ore, driving off other elements as gases or slag and leaving the metal base behind. It is the method of extracting pure elemental copper (Cu) from copper concentrate (CuFeS₂).

Statement 1 is incorrect: Copper smelting generally does not release lethal quantities of carbon monoxide (CO) into the environment.

Statement 2 and 3 are correct: Some smelting processes can also produce large quantities of solid waste, known as slag. This slag may leach heavy metals (arsenic, cadmium, lead or mercury depending on the composition of the ore) into groundwater reservoirs. Smelting processes are known to emit high quantities of air pollutants such as hydrogen fluoride, sulphur dioxide, oxides of nitrogen, offensive and noxious smoke fumes, vapours, gases, and other toxins.

Explanation

Statement 1 is correct: 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.

Statement 2 is correct: Marine engines and slow speed engines use Furnace oil for power generation, they are used for drying tea leaves. Thermic fluid heaters and hot air generators also use Furnace oil.

Statement 3 is correct: The emissions of oxides of sulphur are a direct result of the sulphur content of the fuel oil.

Explanation

Magnetite particles are a highly magnetic mineral form of iron and are known to be present in air pollution. Exposure to airborne particulate matter (PM) is associated with pulmonary, cardiovascular and neurological problems.

Option 1 is correct: Vehicle brake systems are the major source of airborne magnetite at the roadside.

Option 2 is correct: Petrol and diesel-engine exhaust are also a source of airborne magnetite.

Option 4 is correct: Other sources of Magnetite pollution include Power plants. Options 3 and 5 are incorrect: Household microwave stoves and telephone lines not are established as sources of airborne magnetite particles. Other sources of Magnetite pollution include microwave Stoves within homes, As per WHO, Telephone lines produce low frequency, low energy electromagnetic fields which are the potential source of magnetite particles.

Explanation

The Common Carbon Metric’ is a protocol developed by United Nations Environment Program’s Sustainable Buildings & Climate Initiative (UNEP-SBCI) for measuring energy use & reporting GHG emissions from Building Operations. Its purpose is to support greenhouse gas (GHG) emission’s reductions through accurate measurement of energy efficiency improvements in building operations.

Explanation

Blue Carbon is the carbon captured by the world’s ocean and coastal ecosystems. There are three types of coastal ecosystems -- mangroves, seagrasses and tidal marshes; these store half the "blue" carbon buried beneath the ocean floor. These areas absorb and store carbon at a much faster rate than other areas, such as forests, and can continue to do so for millions of years. The carbon found in coastal soil is often thousands of years old.

Explanation

Statement 1 is correct: The NYDF was launched and endorsed at the United Nations Climate Summit in New York on September 23, 2014. It was a significant global effort to address deforestation and promote forest conservation.

Statement 2 is correct: The NYDF sets a global timeline to end natural forest loss by 2030 and to restore 350 million hectares of degraded forest and agricultural land by the same year. It also aims to halve deforestation by 2020 (though this target was not met).

Statement 3 is incorrect: The New York Declaration on Forests (NYDF) is a voluntary and non-legally binding international declaration aimed at ending global deforestation.

Statement 4 is correct: The NYDF has been endorsed by a wide range of stakeholders, including national governments, multinational companies, NGOs, and indigenous communities. Over 200 entities have pledged their support.

Statement 5 is incorrect: India was not a signatory to the NYDF at its inception. While many countries, including the United States, Canada, and several European nations, endorsed the declaration, India has still not joined as a signatory.

Explanation

Option 1 is correct: 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, like a pincushion filled with needles. If attacked they will curl into a prickly and unappetizing ball that deters most predators.

Option 2 is incorrect: Marmot are any of 14 species of giant ground squirrels found primarily in North America and Eurasia. Marmots are well suited for life in cold environments and have small fur-covered ears, short, stocky legs, and strong claws for digging. Marmots do not roll up and protect their vulnerable parts. They often use their sharp teeth and powerful jaws to defend themselves.

Option 3 is correct: Pangolin, also called scaly anteaters be-cause of their preferred diet. They are the most trafficked mammal in the world. If touched or grabbed it will roll up completely into a ball, while the sharp scales on the tail can be used to lash out.

Explanation

Option (c) is correct: Filter feeders are a subgroup of suspension feeding animals that feed by straining suspended matter and food particles from water, typically bypassing the water over a specialised filtering structure. Clams, krill, sponges, oysters, etc are among the creatures that rely on this way of feeding (including some sharks). Filter feeders include some birds like flamingos and several varieties of duck. Filter feeders are regarded as ecosystem engineers since they might be crucial in the clarification of water. They serve as indicator organisms and are crucial in bioaccumulation.

Option (a), (b) and (d) are incorrect:

Catfish are bottom-dwellers that feed on a variety of food sources, including insects, crustaceans, and small fish. Octopuses are predators that feed on crustaceans, mollusks, and fish. Pelicans are birds that feed on fish and other aquatic animals.

Explanation

Statement 1 is incorrect: Oil palm trees are native to West Africa but were brought to South-East Asia over 100 years ago as an ornamental tree crop. Southeast Asia, particularly Indonesia and Malaysia, is the largest producer of palm oil.

Statement 2 is correct: Non-food applications of Palm oil are Cosmetics, toiletries, soaps and detergents. Oleochemical industry, as a base material for laundry detergents, household cleaners and cosmetics.

Statement 3 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.

Explanation

Leguminous plants have small pockets or nodules in their roots that host a specific type of bacteria known as nitrogen-fixing bacteria. Statements 1 and 2 are incorrect: Moringa is a rapidly growing, drought-tolerant tree native to the Indian subcontinent. It is found naturally in the sub-Himalayan regions of Northern India and is now cultivated globally in tropical and subtropical climates. Unlike leguminous plants, Moringa is not a legume and is deciduous, shedding its leaves seasonally. On the other hand, tamarind, a leguminous tree known for its edible fruit, is native to tropical Africa, not South Asia. Statements 3 and 4 are correct: In India most of the Tamarind is collected as Minor Forest Produce with Minimum Support Price. Tamarind is also actively exported from India.

Statement 5 is correct: Biodiesel is derived from the tamarind seed through the transesterification process as potential alternative feedstock for the diesel engine. Seeds of Moringa too can be used for biodiesel production.