[Mission 2023] STATIC QUIZ, 23 February 2023 – Environment

Solution: d)

A pollinator is an animal that moves pollen from the male anther of a flower to the female stigma of a flower. This helps to bring about fertilization of the ovules in the flower by the male gametes from the pollen grains.

Insect pollinators include bees, (honey bees, solitary species, bumblebees); pollen wasps (Masarinae); ants; flies including bee flies, hoverflies and mosquitoes; lepidopterans, both butterflies and moths; and flower beetles. Vertebrates, mainly bats and birds, but also some non-bat mammals (monkeys, lemurs, possums, rodents) and some lizards pollinate certain plants. Among the pollinating birds are hummingbirds, honeyeaters and sunbirds with long beaks; they pollinate a number of deep-throated flowers. Humans may also carry out artificial pollination.

Solution: a)

Ecological succession, the process by which the structure of a biological community evolves over time. The time scale can be decades (for example, after a wildfire), or even millions of years after a mass extinction.

The community begins with relatively few pioneering plants and animals and develops through increasing complexity until it becomes stable or self-perpetuating as a climax community.

Ecological succession is characterized by increased productivity, shift of nutrients from the reservoirs, increased diversity of organisms with increased niche development, and a gradual increase in the complexity of food webs.

Two different types of succession—primary and secondary—have been distinguished. Primary succession occurs in essentially lifeless areas—regions in which the soil is incapable of sustaining life as a result of such factors as lava flows, newly formed sand dunes, or rocks left from a retreating glacier. Secondary succession occurs in areas where a community that previously existed has been removed; it is typified by smaller-scale disturbances that do not eliminate all life and nutrients from the environment.

Solution: c)

Ocean deoxygenation is the expansion of oxygen minimum zones in the world’s oceans as a consequence of anthropogenic emissions of carbon dioxide. The change has been fairly rapid and poses a threat to fish and other types of marine life, as well as to people who depend on marine life for nutrition or livelihood.

Ocean deoxygenation poses implications for ocean productivity, nutrient cycling, carbon cycling, and marine habitats.

Most of the excess heat from CO₂ and other greenhouse gas emissions is absorbed by the oceans. Warmer oceans cause deoxygenation both because oxygen is less soluble in warmer water, and through temperature driven stratification of the ocean which inhibits the production of oxygen from photosynthesis.

Anoxic waters are areas of sea water, fresh water, or groundwater that are depleted of dissolved oxygen and are a more severe condition of hypoxia.

Solution: c)

In situ bioremediation is the application of a biological treatment to clean up hazardous compounds present in the environment. Some of the in-situ bioremediation practices are:

Biosparging: This involves the injection of air under pressure below the water table to increase ground water oxygen concentrations and to enhance the rate of biological degradation of contaminants by naturally occurring bacteria. Biosparging increases the mixing in the saturated zone and thereby increases the contact between soil and ground water.

Bioaugmentation: Bioaugmentation is the introduction of a group of natural microbial strains or a genetically engineered strain to treat contaminated soil or water. Most commonly, it is used in municipal waste water treatment to restart activated sludge bioreactors.

Solution: b)

What are invasive animal species?

o Alien species become ‘invasive’ when they are introduced deliberately or accidentally outside their natural areas, where they out-compete the native species and upset the ecological balance.

o Invasive animal species pose a threat to biodiversity and human well-being.

o Common characteristics of invasive species include:

Rapid reproduction and growth,

High dispersal ability,

Phenotypic plasticity (ability to adapt physiologically to new conditions), and

Ability to survive on various food types and in a wide range of environmental conditions.