Biomes are geographical areas that have a particular climate and sustain a specific community of flora and fauna
- The total area where all living things are found (i.e. the totality of biomes) is called the biosphere
There are a number of different biomes that are recognised according to their specific characteristics
- These include forests and grasslands (tropical and temperate), tundras, deserts and mountain ranges
Tropical Rainforest
- Hot climate (25ºC – 30ºC) with very high levels of precipitation (> 250 cm per year)
- Has a large diversity in species and vegetation includes epiphytes, tall trees and undergrowth
Temperate Forest
- Temperate forests (deciduous forests) have moderate temperatures and clear seasonal changes
- They have a growing period of ~200 days during 4 – 6 frost free months
Boreal Forest (Taiga)
- Taigas (coniferous forests) are cold and icy (0ºC – 15ºC) with a small amount of precipitation
- Coniferous trees are densely packed and there is little variation in species
Tropical Grassland (Savannah)
- Savannahs are warm (20ºC – 30ºC) with medium amounts of moisture, although seasonal droughts are common
- Trees are intermittent and widely spaced, with occasional fires preventing thicker vegetation from encroaching
Temperate Grassland
- Temperate grasslands have moderate temperatures and moderate amounts of rainfall
- Trees and shrubs are largely absent and grasses are the dominant vegetation
Mediterranean (Chaparrel)
- Temperatures are moderate (15ºC – 25ºC) with rainy winters and dry summers
- Vegetation consists of dry woody shrubs that are quick to grow
Desert
- Deserts have extreme temperature conditions (> 30ºC during day ; < 0ºC at night) and very low precipitation
- Dominant plant species are xerophytes which are adapted for water conservation (rainfall is < 30 cm per year)
Tundra
- Tundras have freezing temperatures (< 0ºC) and very little precipitation
- Vegetation is low growing (e.g. mosses), although perennial plants may grow during the summer
Mountain Ranges
- Mountain ranges are found all over the world at high altitudes (> 10,000 feet)
- Temperatures are typically fairly low due to the altitude, although weather conditions may change rapidly
Distribution of Biomes within the Biosphere
All
Rainforest
Temperate Forest
Taiga
Savannah
Grassland
Chaparrel
Desert
Tundra
Mountain
Ocean