Lesson 14: Biodiversity of Glaciated and Periglacial Landscapes Flashcards
Growing season length in tundra?
3 months
Temps in this growing season
12 degrees
Area covered by vegetation in periglacial environmnts?
8 million km2
Vegetation in lower Arctic latitudes (around 70-75˚N)?
-Continuous cover of ground vegetation including sedges and mosses in the wetter hollows and scattered dwarf trees (elder and birches) on the lower ridges.
-Heaths, grasses and rapidly flowering plants flourish
Vegetation in higher Arctic latitudes (around 75-80˚N) and higher altitudes
-Polar desert conditions prevail
-Small range of plants survive in favourable sheltered locations such as the purple saxifrage and the arctic poppy
Arctic tundra ecosystem characteristics in summer?
-The surface layer of permafrost melts to form bogs and shallow lakes.
-These attract insects, which in turn attract migrating birds.
-The tundra also supports a variety of larger animals such as the Arctic Fox, grey wolves, snow geese and musk oxen.
Arctic tundra ecosystem characteristics in winter?
-Temperatures fall well below freezing.
-Plants – which many animals rely on for food – must survive under the snow to re-remerge and flower quickly once temperatures rise again in the spring
% of freshwater locked up in ice?
75%
% of water in glaciers?
2%
How much water do the Alps transport a year?
216 km3
Define Arctic amplification
The Arctic region is now warming twice as fast as the global average
What 3 factors make up Arctic amplification?
-White polar sea ice decreases
-Permafrost melts
-More exposed rock and less snow cover
% of carbon stored in permafrost?
14%
How could decreasing permafrost still act as a negative feedback loop?
1) Warmer temperatures accelerate decomposition (releasing carbon) but also increase the release of nutrients.
2) This encourages plant growth and the removal of carbon from the atmosphere through photosynthesis
3) Increased plant growth is a negative feedback, opposing the Arctic amplification
