[Mission 2023] STATIC QUIZ, 11 May 2023 – Environment

Solution: d)

The soil is poor in nutrients and acidic due to frequent leaching by heavy rains.

Frequent rains wash away the top soil leaving only certain mineral and organic remains.

However, rainforests are also notable for replenishing the soil quickly with dead organic matter (e.g. leafs that fall from trees).

Solution: c)

Coral bleaching causes corals to expel tiny photosynthetic algae, draining them of their colour. It calcifies the corals to turn into white. Algae are vital to the coral, which uses the organic products of photosynthesis to help it grow. The loss of algae makes it vulnerable to disease and it will eventually die. When a coral bleach, it is not dead.

Conditions required for growth of corals are warm tropical oceans with minimum temperature of 20 degree; transparent parts of ocean bodies; Oceanic water must be free of sedimentation; it should have relatively low salinity etc. When these conditions are vitiated it may lead to coral bleaching.

Solution: b)

The excess CO2 is used for calcification of reefs and in this way the additional CO2 is taken care of. So, coral reefs are helpful in controlling Green House Effect as they absorb carom dioxide.

They usually form the first barrier against a tsunami or cyclone or sea waves by blocking the force of the wave. They have the highest primary productivity within the sea, not outside. Amongst all, estuaries are the one with the highest primary productivity.

Solution: d)

• Algae can be used to make Biodiesel and Bioethanol.
• It is a complete protein with essential amino acids (unlike most plant foods) that are involved in major metabolic processes such as energy and enzyme production.
• They are used as fertilizers, soil conditioners and are a source of livestock f
• Algae are used in Wastewater Treatment facilities, reducing the need for greater amounts of toxic chemicals than are already
• Algae can be used to capture fertilizers in runoff from farms.

Solution: a)

Reef-building corals are restricted in their geographic distribution by factors such as the temperature and the salinity (salt content) of the water. The water must also be clear to permit high light penetration.

Because of these environmental restrictions, reefs generally are confined to tropical and semitropical waters. The diversity of reef corals (the number of species), decreases in higher latitudes up to about 30° north and south, beyond which reef corals are usually not found.

Generally, there are about twice as many coral species in Pacific Ocean reefs as in Atlantic Ocean reefs.