Earth Life Support Systems Pt2- Tundra Flashcards
What is the location of the Tundra?
It is found in the Northern hemisphere.
It covers 8 million km squared.
What are examples of countries that the Tundra may be found?
Alaska
Siberia
North Canada
What is the climate like in the Tundra?
Extremely cold climate- 8 to 9 months of negative heat balance.
Winter temps can reach below -40 degrees.
Low precipitation.
What is negative heat balance?
Where average temps in the tundra are below freezing.
How much precipitation does the Tundra recieve?
50-300mm pa
What lies under a lot of the tundra?
Permafrost
When does the active layer thaw in the Tundra?
In the Summer
How much plants and animals can be found in the Tundra?
Low biodiversity
Treeless
Animals are well adapted to extreme conditions, such as arctic fox and hare.
Why is the Tundra treeless?
Extreme temps
What type of vegetation can be found in the lower arctic?
Continuous
What type of vegetation can be found in the higher arctic?
Discontinuous
What are the flows in the water cycle in the Tundra?
Low annual precipitation
Low evaporation
Permafrost is a barrier to infiltration, percolation and groundwater flow.
Why is there low evaporation?
As ground temperature remains low therefore most of the year the surface/soil water is frozen.
What are the stores in the water cycle in the Tundra?
Low absolute humidity
Limited groundwater and soil moisture stores.
During the summer a thermokarst landscape exists
What does low absolute humidity mean?
Little moisture stored in the atmosphere due to the low temps.
Why is there limited groundwater and soil moisture stores?
Due to the permafrost
What does a thermokarst landscape create?
It forms a temporary store of liquid water as wetlands, ponds and lakes can’t drain due to the permafrost.
What are the flows in the carbon cycle in the Tundra?
Carbon flux mainly in summer.
Carbon rich litter contributes to soil during growing season.
CO2 released to atmosphere during summer.
Permafrost increasingly seen as a carbon source due to global warming.
When does the carbon flux mainly occur in the Tundra?
In the summer when the active layer thaws and long hours of daylight allow plants to grow rapidly.
How is CO2 released to the atmosphere in the Tundra if there’s little vegetation?
Due to respiration of micro-organisms during the summer.
What are the stores of the carbon cycle in the Tundra?
The amount of carbon stored in the soils is 5X that in above ground biomass.
High amounts of carbon locked up in permafrost.
What’s the amount of biomass in the Tundra?
4-29 tonnes/ha
What’s the NPP in the Tundra?
200g/m squared/ year
