Distribution and Characteristic of Biomes (Edexcel IGCSE Geography)

• There are 11 biome in Earth's biosphere

Biome Distribution

• Latitude: with distance from the equator temperatures and sunshine hours decrease 
• Precipitation: areas of high pressure experience low rainfall, areas of low pressure experience high rainfall
• Altitude: Increases in altitude lead to decreases in temperature
• Continentality: locations further inland heat up more quickly in the summer and cool more quickly in the winter
• Ocean currents: warm and cold currents circulate in the oceans either warming or cooling the adjacent land 

Distribution of the World Biomes

Characteristics of Tropical Biomes

Characteristics	Tropical Rain Forest	Tropical Monsoon Forest
Location	Low latitudes Within the Tropics 23.5° north and south of the equator Amazon in South America, New Guinea, Southeast Asia, Zaire Basin	5° - 30° north and south of the equator India, Central America, Southeast Asia
Annual Precipitation	Over 2000mm	Between 700 - 2000mm
Temperature Range	26-28°C	30-45°C in summer and 15-30°C in winter
Seasons	No seasons - hot and wet all year round	Three seasons  Cool, dry Hot, dry Rainy season
Growing Season	All year round	During the rainy season and cool, dry season
Soils	Infertile due to leaching and rapid uptake of nutrients by plants
Biodiversity	about 50% of the world's plant and animal species live in the rainforest biome Four layers of vegetation: mahogany, teak trees, lianas, orchids Toucans, jaguars, frogs, snakes	High levels of biodiversity Hardwood, deciduous trees, teak, mahogany, lianas and orchids Monkeys, parrots, jaguars, panthers, snakes, frogs

Characteristics of Temperate & Boreal Forest Biomes

Characteristics	Temperate Forest	Boreal Forest
Location	Between 40°-60° north and south of the equator Western Europe, North-east USA, Eastern Asia	Between 50°-60° north and south of the equator Canada, Russia, Scandinavia
Annual Precipitation	750-1500mm	300-900mm
Temperature Range	Over 0°C in winter and summer between 20°C-25°C	-30°C in winter and up to 20°C in summer
Seasons	Four seasons of equal length	Two main seasons - winter and summer
Growing Season	6-8 months	2-3 months
Soils	Fertile soils Nutrient rich due to decomposition of organic matter over autumn and winter	Not very fertile often acidic and contains permafrost Shallow soil with a thick litter layer due to slow decomposition
Biodiversity	Wide range of animals and plants Deciduous trees: beech, oak, birch Deer, rabbits, squirrels, bears	Less biodiverse than temperate forests Coniferous trees  Squirrels, bears, reindeer, wolves

Characteristics of Tropical and Temperate Grassland Biomes

Characteristics	Tropical Grasslands	Temperate Grasslands
Location	North and south of the tropical and monsoon forest biomes 5°-30° north and south of the equator Central Africa - Tanzania, Kenya	The Velds of South Africa, the Pampas of Argentina, and Steppes of Russia and the plains of the USA 40°-60° north and south of the equator
Annual Precipitation	800-900mm	250-750mm
Temperature Range	15°C to 35°C	-40°C to 40°C
Seasons	Wet and dry season	Four seasons
Growing Season	During the wet season (4-5 months)	During the summer (dependent on temperature)
Soils	Free draining with a thin layer of humus Not very fertile most nutrients near the surface	Fertile soil
Biodiversity	Wide range of plant and animal species  Grasses, baobab and acacia trees Zebras, elephants, giraffes Greatest diversity of hoofed animals	Large numbers of plant and animal species Grasses, sunflowers Bison, antelopes, rabbits Grasses and trees

Characteristics of Desert Biomes

Characteristics	Hot Desert
Location	15° - 30° north and south of the equator North Africa - Sahara, Southern Africa - Kalahari and Namib, Australia. Middle East
Annual Precipitation	Below 250mm
Temperature Range	Daytime temperatures can reach 50°C but average around 25°C Night time temperatures below 0°C
Seasons	Summer and winter
Growing Season	All year round
Soils	Infertile
Biodiversity	Low diversity Cacti, yucca Spiders, scorpions, camels, meerkats

Characteristics of Tundra Biomes

Characteristics	Tundra
Location	North of the Arctic Circle and Antarctica
Annual Precipitation	Less than 250mm
Temperature Range	Below 0°C for 6-10 months
Seasons	Winter and summer
Growing Season	6-10 weeks
Soils	Thin infertile soil Permafrost
Biodiversity	Low biodiversity Arctic fox, polar bears, snowy owls. Arctic wolves, Arctic hares, caribou Small grasses, mosses, lichen