Environment and Ecology Mixed Practice — MCQs with Answers (Set 11)

The correct ascending order is Maharashtra, Madhya Pradesh, Odisha, Chhattisgarh. Chhattisgarh has the highest forest-cover percentage of the four, Maharashtra the lowest, per Forest Survey of India data (UPSC CSP 2019, Q33).

The correct answer is ‘about a decade or two’. Methane oxidises into carbon dioxide and water vapour within roughly a decade or two. This is far shorter than carbon dioxide’s own atmospheric lifetime.

The correct answer is option 1. Methane hydrate is a solid, ice-like structure where water molecules cage in methane gas. It forms only under high pressure and low temperature.

The correct answer is (c) — corresponding to option ‘1, 2 and 3’ here. All three statements are correct. Warming can release trapped methane, large deposits sit in Arctic tundra and under the seafloor, and atmospheric methane oxidises to CO2 within a decade or two.

The correct answer is Urticaceae, the nettle family. Its stinging leaves are typical of this family, while its stem yields the strong fibre used for cloth.

The correct answer is Allo. Himalayan nettle’s bast fibre is called allo across much of Nepal, where it has long been hand-spun into cloth.

The National Chambal Sanctuary is genuinely home to the Gharial and the Gangetic River Dolphin, along with the Mugger crocodile, smooth-coated otters, and several freshwater turtle species. It does not host the Irrawaddy Dolphin, which lives in Chilika Lake and Southeast Asian rivers instead.

Chilika Lake in Odisha holds the world’s largest single lagoon population of the Irrawaddy Dolphin. The species is Endangered on the IUCN Red List, with fewer than 7,500 individuals estimated worldwide. It is not found in the Chambal River.

The correct answer is 1 and 3 only. The Blue-finned Mahseer genuinely lives in the Cauvery River, and the Rusty-spotted Cat genuinely occurs in the Eastern Ghats. The Irrawaddy Dolphin is not found in the Chambal River; its main Indian population lives in Chilika Lake, Odisha.

The correct answer is that microbeads are too small for most sewage treatment plants to filter out. They wash down the drain after use and pass straight through treatment. This lets them reach rivers, lakes, and oceans untreated.

The correct answer is 2015. The Microbead-Free Waters Act was signed into law in December 2015. It banned manufacture of microbead cosmetics from July 2017, and sales from July 2018.

The correct answer is (a). Microbeads are tiny plastic particles used in cosmetics. Sewage plants cannot filter them out, so they enter rivers and oceans. Marine animals often eat them, harming marine ecosystems. This was asked in UPSC CSP 2019, GS Paper I, Q30.

The correct answer is cardamom, pepper, nutmeg and jamun. Wild relatives of these crops grow naturally inside the reserve, which is why scientists treat it as an important genetic reservoir.

The correct answer is 2016. India had already notified Agasthyamala as a domestic biosphere reserve in 2001, and UNESCO added it to its World Network of Biosphere Reserves in 2016.

Correct answer: (A) It converts waste into syngas using an ionised gas at extreme temperature, without directly burning it. A plasma torch ionises gas into an electrically conducting state at temperatures up to 14,000°C. This converts waste into syngas rather than combusting it like an incinerator.

The Asiatic lion (Gir Forest) and the one-horned (Indian) rhinoceros (Kaziranga and other floodplain grasslands) occur naturally only in India. The double-humped Bactrian camel is NOT India-exclusive: it is also naturally found across Central Asia and Mongolia, so statement 2 is false.

Critical Wildlife Habitat marks areas where it has been established that wildlife and forest dwellers cannot realistically coexist.

The Baigas live in the dense sal forests of the Maikal Hills, in Dindori district, Madhya Pradesh.

The Baigas became the first community in India to be given Habitat Rights under the Forest Rights Act.

The definition of Critical Wildlife Habitat is genuinely incorporated in the Forest Rights Act, 2006.

The Union Ministry of Environment does not officially decide and declare Habitat Rights for PVTGs across all of India.

Coral reefs thrive roughly between 30 degrees North and 30 degrees South latitude, in warm, clear, shallow water.

The Coral Triangle spans Indonesia, Malaysia, Papua New Guinea, the Philippines, Solomon Islands, and Timor-Leste, a global biodiversity hotspot.

Coral reefs genuinely host more animal phyla than tropical rainforests, a marker of their biodiversity significance.

Removing Prosopis has been shown to increase native species richness by up to 38% at some sites.