Question

Emergent layer, canopy, understorey and forest floor are the four distinct layers of _________.
(A) natural vegetation
(B) natural river
(C) natural forest
(D) none of these

Answer 1

Hint: The natural vegetation, natural rivers and natural forests are found in various places of India. These rivers, forests or vegetation forms or grows naturally without any human interference.

Complete step-by-step answer:
Natural vegetation is referred to as the plant community which grows naturally without any human aid and has been left undisturbed for a long time by humans. This is also called virgin vegetation. Cultivated crops, orchards and fruits do not form part of natural vegetation but they are a part of the vegetation. The endemic or indigenous species are the natural vegetation, which is purely Indian but exotic plants are those which have come from outside of India. The term which is used to denote plants of a particular region or period is flora. Fauna is referred to as the species of animals. There exist various types of natural vegetation. They are Tropical Evergreen Rain Forests, Dry Deciduous Forests and Scrubs, Deciduous or Monsoon Type of Forests, Semi Desert and Desert Vegetation and Tidal or Mangrove Forests. More than 200 cm of rainfall is received by the tropical evergreen forests and it has a temperature of about 15 to 30 degrees Celsius. They occupy about $7\% $ of the earth’s surface and harbour more than half of the world’s animals and plants. In Natural vegetation, there are four distinct layers, which are emergent layer, canopy, understorey and forest floor.

Thus, option (A) is correct.

Note: The natural vegetation consists of thorny trees and bushes in the regions that receive less than 70 cm rainfall. Trees are also scattered and have long roots to penetrate deep into the soil in order to get moisture.