The arctic tundra occupies
earth's Northern hemisphere, circling the North Pole all the way
down to the evergreen forests of the boreal biomes. The
arctic tundra sees little rainfall, like the cold deserts of
russia. The soil of the arctic tundra is poor in
nutrients, which accounts for the low amount of vegetation.
There is an under-layer of soil called permafrost which
remains completely frozen at all times, allowing little room for
deep rooting plants and trees. The plants that do survive
the frozen landscapes are extremely resilient, and their roots
are close to the surface of the hard soil, as to intake what
little water falls upon the ground; most of the arctic tundra's
plant life consists of shrubbery, lichen, moss, and
flowers. Icy rivers flow through the tundra to the arctic
ocean, and are home to trout, salmon and other freshwater fish.
Sometimes rainfall produces small, temporary ponds, which serve
as mating areas for flies and mosquitoes.
Other animal species occupying
the tundra consist of polar bears, caribou, musk ox, grey
wolves, lemmings, rabbits, squirrels, and birds such as
penguins, falcons, ravens, terns, and loons. All are
greatly adapted to their environment, with extra layers of fat,
and the ability to hibernate during the colder months, although
this has more to do with the lack of food than the cold.
Birds of the tundra migrate south during the winter months,
causing constant change in the animal population.
The alpine tundra biome exists
on rocky mountaintops and is very similar to the arctic tundra
except for a conspicuous lack of trees. Because trees
cannot grow at this high altitude, most of the alpine tundra
plant life consists of shrubbery and small leafy plants such as
alpine bluegrass which serve as dinner to a variety of grazing
animals such as bighorn sheep and mountain goats. Other
alpine tundra animals include elk, pika, marmots, and birds such
as the white-tailed parmigan and the grouse, and a few insects
like grasshoppers, bumblebees, and beetles.