Tropical Forests

 

Tropical forests have steady, year-round temperatures of about 23oC (75oF) and a wide variety of rainfall patterns.

In a very broad way, tropical forests can be classified as:

  • tropical rain forest
  • montane rain forest
  • tropical seasonal forest
  • tropical dry forest

 

Tropical forests once covered 20% of land surface. Two-thirds of these have been degraded or eliminated by:

  • lumbering
  • clearing for plantations
  • settlements
  • agriculture

 

 

 

Tropical Rain Forests

 

The tropical rain forest comes in 30-40 types including:

  • monsoon forest
  • evergreen savanna forest
  • tropical evergreen alluvial forest
  • equatorial lowland tropical rain forest

 

 

 

 

 


 

Tropical Rain Forest, Amazon Basin

 

 

Tropical Rainforest, Malaysia

 

 


 

  • Chimpanzee (Pan troglodytes) inhabits the tropical rainforests of Central Africa.
  • Orangutan (Pongo pymaeus) inhabits the tropical rainforests of Borneo.

 

 

 

 

  • Tropical rain forests can be divided into five vertical layers
    • Emergent trees
    • Upper canopy
    • Lower canopy
    • Shrub understory
    • Ground layer of herbs and ferns

Vertical structure of a tropical rainforest

 

 

 

 

 

 

 

 

 

 

 

  • Rainforest cultivated foods & spices
    • yam
    • coffee
    • chocolate
    • banana
    • mango
    • papaya
    • macadamia
    • avocado
    • sugarcane

 

 

 

 

  • Soils of the tropical rain forests
    • Oxisols characteristic, deeply weathered with no distinct soil profile development
    • Ultisols develop in areas with more seasonal regime
       

 

 

  • In regions of the tropics characterized by greater seasonality in precipitation, the broadleaf evergreen forests are replaced by the dry tropical forests
  • The dry tropical forest undergoes a dry season whose length is based on latitude and supports drought-deciduous trees and shrubs
    • The farther from the equator, the longer the dry season
  • During the dry season, drought-deciduous plants drop their leaves
     

 

A tropical dry forest in Costa Rica during:

  • a) rainy season
  • b) dry season