Arctic Tundra Biome

Question 1

What is the average temperature range annually in the ATB

Answer 1

-5 - -10 degrees C

Question 2

What is the temperature during long dark winters?

Answer 2

-20

Question 3

What causes low annual precipitation?

Answer 3

High pressure and subsiding air

Question 4

What is the annual precipitation?

Answer 4

150mm

Question 5

What is the maximum temperature for the short growing season?

Answer 5

10 degrees C

Question 6

What are the 4 dominant vegetation types?

Answer 6

Mosses, Lichens, Grasses and Dwarf Shrubs

Question 7

What are the main grazers?

Answer 7

Caribou, Musk Ox and Reindeer

Question 8

What are the soils like in the ATB

Answer 8

Thin, acidic and low in nutrients

Question 9

Where do Dwarf Willow and Stunted Birch Trees grow?

Answer 9

Adjacent to seasonal rivers, but only to a maximum height of 30cm due to the short growing season, low nutrient availability and wind exposure

Question 10

How do they help resist the effects of low temperatures and wind/snow damage?

Answer 10

Growing together in a blanket formation

Question 11

What are some other adaptations of tundra flora?

Answer 11

• Ability to grow under a layer of snow
• Ability to carry out photosynthesis in cold temperatures
• For flowering plants to produce seeds and flowers quickly once summer begins

Question 12

How does the permafrost affect the above soil?

Answer 12

Causes waterlogging and gleying (the effect of waterlogging resulting in anaerobic conditions)

Question 13

What adaptations do plants have referring to the permafrost?

Answer 13

They have short roots to avoid the permafrost and small leaves to limit transpiration

Question 14

What does limit plant growth result in?

Answer 14

Limited amounts of litter, so there is a slow decomposition of organic matter to give a thin layer of peat.

Question 15

What does the low temperatures inhibit

Answer 15

Soil formation and the decomposition of organic matter

Question 16

How is the formation of soil horizons prevented?

Answer 16

Bedrock being weathered by freeze-thaw action and being raised to the surface by frost heave.

Question 17

What is the projected rate of retreat for the ATB?

Answer 17

15 miles north every decade

Question 18

What are lichens dependant on?

Answer 18

Winter snow and ice - cannot easily adapt to higher temperatures

Question 19

How will CC affect migratory herbivores

Answer 19

They will need to alter their grazing ranges, and numbers and ability to reproduce will be threatened by inadequate vegetation. Higher temperatures will also prevent lakes and rivers freezing, limiting their ability to migrate so there will be overgrazing and a decline in reindeer herds

Question 20

What will be the effect of incremental permafrost thawing.

Answer 20

It could reach a ‘tipping point’ where the amount of methane already released means temperatures are so high the rest of the permafrost can never recover.

Question 21

What is the positive permafrost carbon feedback?

Answer 21

Currently carbon and methane-storing permafrost is shrinking at an alarming rate as decomposition of organic matter is a heat source - leading to a rise in soil temperatures, further decomposition and increased methane release.