Environment and Ecology Mixed Practice — MCQs with Answers (Set 3)

A barrier can block fish travel and change flows without any visible pollution. The other three are pollution that usually shows in water quality, such as low dissolved oxygen.

The golden mahseer is a Himalayan river fish. The blue-finned mahseer is linked with the Cauvery basin.

The sanctuary is a major refuge for the gharial. It also holds turtles, otters and Ganges river dolphins.

Chilika Lake is the best-known Indian home of the Irrawaddy dolphin. The Chambal supports the Ganges river dolphin instead.

A landslide pushed a wave over the Vajont dam in 1963. The dam stayed standing, which makes it a distinctive case among dam disasters.

The Act creates a National Committee on Dam Safety and a National Dam Safety Authority. State committees and State Dam Safety Organisations handle state roles.

CWC records piping as the failure mode at Panshet. The surge then overtopped Khadakwasla and flooded Pune. This is a cascade of failures.

Intense monsoon rain drove a huge flood into the reservoir. Water overtopped the earthen sections beside the central spillway and washed them away.

The assessment found 33.6% of the studied coast eroding, 26.9% growing and 39.6% stable. This is the share eroding, not a national sea-level forecast.

The Maldives is about 1.5 m high on average, which is why even a small rise threatens its islands.

Floating sea ice already displaces its own weight of water, so its melt barely changes sea level. Ice on land adds new water to the ocean.

Warm water takes more space (thermal expansion), and glaciers and ice sheets on land melt into the sea. Tides and storm surges are short-term effects, not the long-term trend.

NMSHE is one of the eight missions in the 2008 National Action Plan on Climate Change. It supports research and climate planning. It is not a permit office for hotels or roads.

Commercial mining and quarrying are generally prohibited in eco-sensitive zones. Local livelihoods are not all banned, and exact rules depend on each notification.

Carrying capacity asks how much use a place can bear without unacceptable harm. It is not one fixed number. Water supply, trail width, weather and waste services change it.

Himalayan headwaters feed the Indus, Ganga and Brahmaputra systems. The share from ice versus rain differs by basin and season.

Stack controls reduce emissions before they spread. Preventing open waste burning removes another source. Closing windows or using one filter may change personal exposure, but neither fixes citywide emissions. A higher AQI signals worse air.

An inversion can keep cooler air below warmer air. Pollutants then disperse upward more slowly. It does not destroy particles, remove other pollutants, or stop AQI monitoring.

WHO’s 2021 annual PM2.5 guideline is 5 micrograms per cubic metre. India’s notified annual NAAQS is 40. These are annual concentrations, not daily AQI scores. Reversing the numbers gives the wrong comparison.

PM2.5 refers to fine particles no wider than about 2.5 micrometres. It is a size group, not one chemical. The number is not a gas count or an AQI score.

A secondary pollutant forms through reactions in the air. Ground-level ozone is an example. Smoke released directly is primary pollution. Visibility does not define the class. AQI is an index, not a pollutant.

Spiders feed on insects, including some crop pests. Heavy pesticide use can harm these predators. Fewer spiders can weaken one natural check on pests. Spraying does not change a spider into an insect or remove every pest forever.

The field paper reported Gooty tarantulas farther south in the Eastern Ghats of Tamil Nadu. That expanded the known range. It did not change the animal’s biology, remove threats, or amend CITES.

The IUCN assessment calls the Gooty tarantula Critically Endangered. CITES lists the Poecilotheria genus in Appendix II. India’s Wild Life (Protection) Act lists this species in Schedule II. These systems serve different purposes.