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Tropical rainforests - EdexcelCharacteristics of tropical rainforests

Tropical rainforests are an important ecosystem with distinct characteristics and adaptations. Tropical rainforests face threats which need to be managed to ensure their survival.

Part of GeographyEcosystems, biodiversity and management

Characteristics of tropical rainforests

Tropical rainforests have distinct characteristics that support a wide variety of different . This means that they have a high . The or living components of the ecosystem and the or non-living components of the ecosystem depend on one another - a change in one leads to a change in the other.

Climate

  • Very wet with over 2,000 mm of rainfall per year.
  • Very warm with an average daily temperature of 28掳C. The temperature never drops below 20掳C and rarely exceeds 35掳C.
  • The atmosphere is hot and .
  • The climate is consistent all year round. There are no seasons.

Soil

  • Most of the soil is not very .
  • A thin layer of fertile soil is found at the surface where the dead leaves decompose.
  • It is red in colour because it is rich in iron.
  • Due to heavy rainfall the nutrients are quickly washed out of the soil.

Plants and animals

  • The warm and very wet climate provides perfect conditions for plant growth.
  • The wide range of plant supports many different animals, birds and insects.
  • Species have adapted to the conditions of the rainforest, eg trees and plants have shallow-reaching roots to absorb nutrients from the thin fertile layer in the soil.

Structure of a tropical rainforest

A tropical rainforest is made up of the following layers:

  • ground level
  • shrub layer
  • under canopy
  • (main) canopy
Emergents at the top receive most light. Beneath is the canopy, then the under canopy, and lastly the shrub level, receiving the least light.