English Across the Curriculum

Tropical Rainforest

Structure of the rainforest

Rainforests have four layers.

  • The top layer is the canopy. It consists of the tallest trees of the rainforest. They may get over 50 metres tall. But only very few reach this height. This is the part that gets most of the sunlight.
  • The subcanopy is a layer of trees that is below the canopy. More than 70 % of rainforest animals and plant species live in the canopy and subcanopy. Lianas often climb around trees.
  • The understory is the shadowy lower area. It has young trees and plants like ferns or palms that do not need much light. Only 1 or 2 per cent of the sunlight reaches the understory.
  • The floor has a thin layer of leaves, seeds or fruits and branches that fall from the trees. It decomposes fast, and new material takes its place.

When large , tall trees die and fall to the ground, they leave a gap in the rainforest. Very quickly, smaller trees take this place and their crowns grow larger. That's why the layers of the rain forest always change.

 

Rainforest canopy on the Andaman Islands in the Indian Ocean

Image :  © Vyacheslav Argenberg / http://www.vascoplanet.com/, CC BY 4.0,
via Wikimedia Commons