BIOMES

Ecosystems can be small-scale, covering a small area (such as a pond) or large-scale covering a large area (such as a tropical rainforest). The world is divided up into ten major ecosystems. These large-scale ecosystems are called biomes. What are the world’s major biomes?

RAINFOREST

Rainforest in Hawaii - photo courtesy of Sarah Camp

DECIDUOUS FOREST

A deciduous forest in the USA - photo courtesy of Nicholas A Tonelli

CONIFEROUS FOREST 

A coniferous forest in Yosemite, USA - photo courtesy of Gopal Venkatesan

 DESERT

Desert in Merzouga, Morocco - photo courtesy of Antonio Perez Rio

 DESERT SCRUB

Bush scrub in Northern Territories, Australia

 GRASSLAND

Bison grazing in Custer State Park, South Dakota

 SAVANNAH

Migrating wilderbeest and zebra on the Serengeti plains, Tanzania

TUNDRA

Tundra in Colorado - photo courtesy of Hun Lim

MOUNTAIN 

Mount Everest seen from Gorak Shep

 MEDITERRANEAN/CHAPARRAL

Lasithi Plateau, Crete - photo courtesy of Phil Yorke

Biomes are large-scale ecosystems defined by abiotic factors. These are:

• climate
• relief
• geology
• soils
• vegetation

Where are the world’s major biomes?

Biome characteristics

• Tropical forests are found near the equator in Central and South America, parts of Africa and Asia. They are hot and humid and contain a huge variety of plants and animals - around half of all the world's species. The trees are mostly hardwood. The climate is called equatorial.
• Savannah or tropical grasslands are hot and dry, dominated by grass, scrub and occasional trees. They have two distinct seasons - a dry season when much of the vegetation dies back, and a rainy season when it grows rapidly. They are found in central Africa (Kenya, Zambia, Tanzania), northern Australia and central South America (Venezuela and Brazil).
• Desert is the driest and hottest of areas. The world's largest desert is the Sahara in North Africa. Areas of scrub land that border the desert are called desert scrub.
• Mediterranean/Chaparral climates are not too hot or cold. They are found around the Mediterranean Sea, near Cape Town in South Africa and Melbourne in Australia.
• Temperate grasslands are dominated by grass and trees and large bushes are scarce. They have a temperate continental climate - the weather is mild with moderate rainfall. Grasslands include the Puszta in Hungary, the Veldt in South Africa, the Pampas in Argentina and the Prairies in the USA.
• Temperate deciduous forests contain trees that lose their leaves and are found across Europe and USA. The weather is mild and wet. The climate is called temperate maritime.
• Coniferous forests, containing evergreen trees, are found in Scandinavia, Russia and Canada. They have a cool climate with moderate rainfall called cool temperate.
• Mountain areas can be very cold at night and during winter. The growing season is short and at higher levels trees will not grow.
• Tundra surrounds the North and South poles. They have an extremely cold climate, with limited numbers of plants and animals able to survive there.

Courtesy: BBC