Forest(Continued)

The most common type of natural vegetation on the earth. Forest refers to large areas of land that are dominated by trees and a variety of other plants. Forest vegetation is usually found at places where the temperature ranges from 12 to 30 degree Celsius and annual rainfall ranges from 300mm to 2000mm. The type of forest and their characteristics depend on the climate and they vary from place to place. A typical forest has five layers. Different heights of the natural vegetation form the different layers in the forest.

Tropical rainforests
- The structure of the forest
The area of tropical rainforest looks like an untidy clump of trees. However, there is a structure or a particular way in which the plants grow. Tropical rainforest can be divided into five distinctive layers according to height. Each layer has its own characteristics and types of plants.

5 layers of the tropical rainforest:
-Emergent layer
Tall trees called emergents, reach a height of 30m to 50m. Their crowns appear above the canopy layer. These trees have tall, thick and straight trunks.

- Canopy layer
The trees in this layer reach a height of 15m to 30m. A wide, shallow and umbrella- shaped crowns form a continuous leaf cover, called the canopy. It prevents sunlight from penetrating to the lower layers of the forest.

- Understorey layer
The trees here have narrower, oval-shaped crowns because most of the sunlight is blocked by the canopy. These trees grow where there are gaps in the canopy that allows sunlight to pass through. Their height ranges from 6m to 15m. Young trees of the emergent and canopy layer are also found in this layer.

- Shrub layer
Tree saplings(young trees) and woody plants are found in this layer. They may grow up to 6m high.

- Undergrowth layer
The undergrowth layer or the forest floor consists of grasses, ferns, mosses and fungi. Plant growth is sparse(not thick) due to little sunlight reaching this layer. Plants in this layer grow to a maximum height of 5m.