UPSC Static Quiz – Environment : 27 March 2026

Solution: C

• Statement 1 is incorrect because desert soils are notoriously poor in organic matter; high temperatures lead to the rapid oxidation of any organic debris, and the lack of moisture inhibits the activity of decomposers.
• Statement 2 is incorrect; desert animals are typically nocturnal or crepuscular (active at dawn/dusk) to avoid the lethal diurnal heat.
• Statement 3 is incorrect; desert plants (xerophytes) actually minimize leaf surface area—often reducing leaves to spines or scales—to reduce transpiration. They use their green stems for photosynthesis (cladodes) or develop succulent tissues to store water.

Solution: A

• Statement 1 is correct. India became a party to CITES in 1976. CITES is an international agreement between governments that aims to ensure that international trade in specimens of wild animals and plants does not threaten their survival. The Wildlife (Protection) Act, 1972, provides the legal framework for the implementation of CITES provisions in India, and the 2022 amendment further strengthened this by aligning the schedules with CITES appendices.
• Statement 2 is correct. The Wildlife Crime Control Bureau (WCCB) is a statutory multi-disciplinary body established by the Government of India under the Ministry of Environment and Forests, to combat organized wildlife crime. It was constituted under the provisions of the Wildlife (Protection) Act, 1972, following a 2006 amendment. Its mandate includes collecting intelligence, establishing a centralized wildlife crime data bank, and assisting state governments in enforcement actions.
• Statement 3 is incorrect. CITES, like most international conventions, is not self-executing. It operates through the national laws of its member countries. While India has an obligation to implement the provisions of CITES, this is done through its domestic legislation, primarily the Wildlife (Protection) Act, 1972. International bodies do not have direct enforcement powers within India’s jurisdiction; enforcement is carried out by Indian authorities under Indian law. The convention provides a framework, but the legal power and enforcement mechanism are domestic.

Solution: C

Membrane Bioreactors (MBRs) combine a membrane process like microfiltration or ultrafiltration with a biological wastewater treatment process, typically a suspended growth bioreactor. They are advanced systems used for municipal and industrial wastewater treatment, offering advantages like high effluent quality and smaller footprint compared to conventional systems.

Option (a) refers to a method for plastic pollution control, not the primary function of MBRs.

Option (b) describes constructed wetlands, which are different from MBR technology.

Option (d) refers to bioremediation using specific organisms, not necessarily MBRs.

Solution: B

• Agriculture is a dominant contributor to the global methane budget.
• Statement 1 is incorrect; globally, enteric fermentation (the digestive process in ruminant animals) is actually the largest source of agricultural methane, followed by rice cultivation. In India, however, both are highly significant.
• Statement 2 is correct; traditional rice farming involves keeping fields continuously flooded, which prevents oxygen from entering the soil. This creates an anaerobic environment where methanogens thrive by decomposing organic matter and releasing methane as a byproduct.
• Statement 3 is correct; AWD involves allowing the water level to drop below the soil surface periodically, introducing oxygen and disrupting the methanogenic process. This technique not only reduces greenhouse gas emissions but also saves significant amounts of irrigation water and can even increase farmer income through the generation of carbon credits. This triple-win scenario (emissions, water, income) is a cornerstone of climate-smart agriculture.

Solution: D

• Nitrous Oxide (N₂O) is primarily released from agricultural soils due to the application of synthetic nitrogenous fertilizers. Microbial processes such as nitrification and denitrification in nitrogen-rich soils convert applied nitrogen into nitrous oxide, a potent greenhouse gas. Hence, I–2 is correct.
• Methane (CH₄) emissions in agriculture are strongly associated with flooded paddy fields. In waterlogged conditions, anaerobic decomposition of organic matter by methanogenic bacteria produces methane. Rice cultivation under continuous flooding is therefore a significant source of agricultural methane emissions. Thus, II–1 is correct.
• Nitrates as pollutants arise mainly due to fertilizer leaching into groundwater. Excess nitrogen fertilizers not absorbed by crops dissolve in irrigation or rainwater and percolate into groundwater aquifers, leading to nitrate contamination. This contributes to eutrophication and health issues such as methemoglobinemia (“blue baby syndrome”). Hence, III–3 is correct.