Arctic Tundra Flashcards
What area does Tundra occupy?
8 million km^2 in Canada, Alaska and Siberia
What is the heat balance in the Tundra?
Negative heat balance 8-9 months a year
What is the mean annual precipitation?
50-350mm mostly as snow
What is biodiversity like?
Low biodiversity
Why is there limited transpiration?
Sparse vegetation and short growing season.
What does the heat balance mean for water?
Surface and soil water are frozen for most of the year
Why are there low rates of evapouration?
Most energy is used to melt the snow.
What is permafrost a barrier to?
infiltration, percolation, recharge and groundwater flow.
What happens in spring?
The spring melt opens up the active layer and causes a spike in river flow. Extensive wetlands and lakes on the tundra into summer. This is only a temporary store of water as permafrost impedes the drainage.
The flux of carbon is concentrated
How large is the permafrost carbon sink?
1600GT
What are the levels of decomposition?
very slow for plant material.
How much more carbon is in the soils than above ground biomass?
5 times more. Biomass is small, between 4-29 tonnes/ha
What is NPP?
Net Primary Productivity is less than 200grams/m^2/year
What is climate change doing to tundra?
Melting permafrost, moving the tundra from a carbon sink to a carbon source. Increased temperatures do mean increased growth which may have a balancing effect.
When and where were oil and gas discovered?
Prudhoe Bay 1968
