rapidly after the water recedes. Permanently
water-logged surfaces, in many cases underlain
by peat, are common in all these regions. In
Canada, the name “muskeg” is applied to such
surfaces.
This is the habitat of large ground animals—a
population which derives most of its food supply
from the aquatic life of the numerous lakes,
rivers, and swamps. In these forests roam the
world’s chief fur-bearing animals: minks,
martens, foxes, wolves, badgers, bears, beavers,
squirrels, sables, and ermines. There are several
large ungulata, chief of which are deer, moose,
the caribou, and reindeer.
References
Brown J, Ferians OJ, Heginbotton JA, Melnikov ES (eds)
(1997). Circum-arctic map of permafrost and ground
ice conditions. U.S. Geological Survey, Scale
1:10.000,000, Washington, DC
Flint RF (1971) Glacial and quaternary geology. Wiley,
New York, 892 pp
Ko ¨ppen W (1931) Grundriss der Klimakunde. Walter de
Gruyter, Berlin, 388 pp
Trewartha GT (1968) An introduction to climate, 4th edn.
McGraw-Hill, New York, 408 pp
Walter H, Harnickell E, Mueller-Dombois D (1975)
Climate-diagram maps of the individual continents
and the ecological climatic regions of the earth.
Springer, Berlin, 36 pp, with 9 maps
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5 Ecoregions of the Continents: The Polar Ecoregions