Unit 6 - Part 1 Flashcards
What percentage does of the Earth’s surface does Arctic Tundra cover?
20%
At what latitudes is the tundra biome found?
between 60 and 80 degrees north and south of the equator
What are the average summer and winter conditions of the tundra biome?
summer = 8 degrees
winter = 3 degrees
What is the annual precipitation average for the tundra biome?
250mm
What are the key characteristics of the soil in the tundra biome?
- permafrost
- frozen ground (gelisols)
- thin
What does the formation of Gelisols require?
permafrost to be within 100cm of the soil surface
store large quantities of organic carbon
very few plants can survive
What is meant by cryoturbation?
when soils freeze and thaw often, makes the soil heave and buckle
How does global atmospheric circulation account for the cold dry climate of the arctic tundra regions?
- located in the polar cell
- area of high pressure
- low angle of incidence
- energy/insolation spread against a large surface area
What is permafrost?
permanently frozen ground for at least 2 consecutive years
Why can gelisols soil not support a significant amount of vegetation?
low nutrient availability
frozen water, cannot access = cannot grow
What are three examples of plants that can survive in the arctic tundra biome?
Cotton grass, Arctic moss and Dwarf Willow and Burch
How is cotton grass adapted to survive in the Arctic Tundra?
- low lying, snow covers in the winter to help insulate
- seeds that scatter in the wind
- narrow leaves, reduce transpiration
- darker leaves, help absorb energy from the sun for photosynthesis
How is the Arctic moss adapted to survive in the Arctic tundra biome?
- grows close to the ground to protect it from the strong winds
- many small leaves, to maximise photosynthesis in the short growing season
- reproduce by growing shoots or sending out spores
- slow growing
How is the Dwarf Willow and Burch adapted to survive the Arctic Tundra biome?
- only grow a maximum height of 30cm, often grow horizontally due to the wind
- short growing season, low nutrient availability and moisture restricts growth
How many species of animal is located in the Arctic tundra biome?
48 species = land mammals
What are the levels of biodiversity like in the Arctic tundra biome?
biodiversity is low due to the harsh climate and limited productivity, slightly increases in the summer
How are Caribou adapted to survive in the Arctic tundra biome?
- short ears
- small tails
- compact bodies
- two insulating layers of fur
How is the Arctic fox adapted to live in the Arctic biome?
- thick layers of fur
- small ears
- colour of fur help with camouflage
- large tail, use it as fur
What is an example of an indigenous people who live in the Arctic biome?
Gwitchin
Why are there rarely no more than 4 trophic levels in the Arctic Tundra food web?
- due to harsh conditions, only a small number of producers, not enough energy to support more levels
How does anthropogenic climate change affecting the Arctic?
Arctic Amplification
because permafrost underlies over 50% of the land surface
How much have tundra areas temperature increased due to melting permafrost?
4 degrees
How many more time potent is methane than c02?
23 times more potent
What is the climate tipping point?
a critical threshold that when crossed, leads to accelerated and irreversible changes to the climate system
What is arctic greening?
when the tundra biome is pushed further north, due to the changes to the climate and landscape
area becomes Boreal (pine forest)
What is an example of a population that has been affected by arctic greening?
Snow geese has increased in the Arctic due to the warming climate
How have snow geese influenced the land in the Arctic?
have turned fertile grassland, into salt mud flats
in 1980’s 2-3 million geese
now 15 million
What was the difference between the area covered in salt mud flats in Canada in 1988 compared to 2011?
1988 = 200sq km3
2011 = 1,300sq km3 (because of geese)
