[Mission 2023] STATIC QUIZ, 29 March 2023 – Environment

Solution: a)

Soil Organic Matter (SOM) is mainly composed of carbon, hydrogen and oxygen but also has small amounts of nutrients such as nitrogen, phosphorous, sulphur, potassium, calcium and magnesium contained within organic residues.

After carbon enters the soil in the form of organic material from soil fauna and flora, it can persist in the soil for decades, centuries or even millennia. Eventually, SOC can be lost as CO2 or CH4 emitted back into the atmosphere, eroded soil material, or dissolved organic carbon washed into rivers and oceans.

Solution: d)

Saltmarshes are one of the key coastal ‘blue carbon’ habitats, recognised for their ability to store carbon within above- and below-ground biomass and sediments.

Saltmarshes sequester carbon at a rate two to four times greater than that recorded for mature tropical forests.

Solution: a)

Under it, CO2 gas is injected with residual oil in the ageing field in which total oil production has been declining.

It reduces its viscosity and makes it easier to displace oil from the rock pores. CO2 gas also swells oil, thereby pushing it towards the producing well for extraction.

CO2- Enhanced Oil Recovery (EOR) works most commonly by injecting CO2 into already developed oil fields where it mixes with and ‘releases’ the oil from the formation, thereby freeing it to move to production wells. CO2 that emerges with the oil is separated in above-ground facilities and re-injected into the formation.

Solution: d)

Oceans are one of the largest carbon sinks on earth because of their large geographical coverage and presence of rich population of phytoplankton and seagrass, which act as carbon sink.

Carbon dioxide readily dissolves in water and the oceans provide a huge reservoir of carbon. Across the world’s oceans there is a continual cycle of equilibration of dissolved carbon dioxide in water with carbon dioxide in the atmosphere.

The difference in partial pressure of the CO₂ between seawater and air facilitate gaseous exchange. This allows atmospheric CO2 to dissolve in seawater.

The carbon dioxide which dissolves in our oceans occurs in three main forms. Aside from the normal carbon dioxide form, it is also found as bicarbonate and carbonate ions.

Solution: b)

The Formation of Smog

• Photochemical smog (smog) is a term used to describe air pollution that is a result of the interaction of sunlight with certain chemicals in the atmosphere.
• One of the primary components of photochemical smog is ozone.
• While ozone in the stratosphere protects earth from harmful UV radiation, ozone on the ground is hazardous to human health.
• Ground-level ozone is formed when vehicle emissions containing nitrogen oxides (primarily from vehicle exhaust) and volatile organic compounds (from paints, solvents, printing inks, petroleum products, vehicles, etc.) interact in the presence of sunlight.