The Tundra

Tundra

• Located north of the Arctic Circle

Tundra

• Frigid temperatures in the winter - with little or no sunlight.

• Temperatures range from 0 to 10 C year round!

• Precipitation less than 100 mm (10 cm) per year

• The frozen desert!

Summer in the tundra

• A few weeks above freezing – short summers!• 24 hours of daylight/day– Plants must act fast!

Tundra - conditions

• Only the top few centimeters of soil thaw• Underneath = permafrost, a layer of soil that

is permanently frozen• Trees cannot grow here

Tundra

• Dominated by tough grasses, shrubs, lichens and herbs.

Tundra

• Dotted with bogs and swamps during summer• Wet areas = breeding grounds for swarming

insects such as……..

Mosquitoes

Blackflies

And the birds that eat them

And the birds that eat other things

Vegetation of the Tundra

• Mosses and lichens• Grow without soil

Vegetation - adaptations

• Plants– very shallow roots – Help anchor them against the icy winds

Vegetation of the Tundra

Examples: Campion and gentian

Vegetation of the Tundra

• Grow close to the ground– Absorb heat from the soil– Keeps out of the wind

Woody plants and perennials

Willow and juniper – but in dwarf forms• Grow flat or along the ground

Animals of the Tundra

• Abundant food – especially insects• NO reptiles or amphibians!

Animal adaptations

• Burrow underground• Camouflage• Well insulated!• Avoid bad conditions by– Migration– Hibernation

The tundra swan

The tundra swan

• Migrates : Breeds in the tundra during the summer

Animals of the Tundra

• Caribou• Migrate throughout the tundra in search of

food and water

Animals of the Tundra

• Hunters - wolves, ermine, fox, owl – camouflage!

Musk ox

Musk ox

• Grows two layers of fur – one short and one long

• Air gets trapped in the short layer of fur and is warmed by the body

• The trapped air acts as insulation• The long fur protects against wind and

water

Musk ox

• Layer of fat• Hooves that are large and hard to break

through ice.

The Musk Ox – leftover from the ice age

The Musk Ox (from Planet Earth)

lemmings

• Small rodents• Can give birth every

5 weeks!• Live in burrows

under or in the snow in winter

lemmings

• Food for plenty of predators!

……..like the ermine

But – don’t always believe what you hear!

lemmings

Threats to the Tundra

• One of the most fragile biomes• Relatively simple food chains – easy to disrupt• Land is easily damaged and slow to recover

Oil – Prudhoe Bay in northern Alaska

Oil exploration

• Transportation damages the permafrost

Pollution

• Caused by spills, leaks of oil or other toxic materials