With great biodiversity spread in a four-layer canopy structure, warm temperatures, low latitudes and high rainfall, the tropical rainforest is an important biome of the world. More than half of living species are found in the tropical rainforest. However, human activities have caused deforestation and many species living in the rainforest are today endangered.
Located in areas of tropical wet climates, rainforests have average annual rainfall between 80 inches and 430 inches. Tree transpiration also contributes to increased humidity and cloud formation in rainforest areas, as a single canopy tree can lose about 200 gallons of water per year, through transpiration. The Amazon rainforest, for instance, creates about 50 percent of its own precipitation.
Warm Temperature and Low Latitude
With average temperatures ranging from 72 to 93 degrees Fahrenheit and very little fluctuation during the year, most tropical rainforests are warm all year round, except those at higher elevations. Situated within the tropics, most rainforests are found nearby the Equator, in areas of latitude lower than 23 degrees North and South.
The tropical rainforest is the richest biome in the world, containing more species per square mile than any other forest. A tropical rainforest can have more than 480 tree species per hectare, while the United States and Canada have about 700 species together. Insects species are the most abundant in the rainforests. A bush in the Amazon is likely to have more ant species than the entire Britain.
Four-Layer Canopy Structure
Rainforests feature a distinct canopy structure of four main levels: the overstory, with 130 feet trees is the highest level; the canopy ceiling contains trees with heights between 100 and 130 feet; the understory, which contains trees and shrubs about 20 to 60 feet above the floor; and the ground level or forest floor, which receives less than 2 percent of the available sunlight.