Hardy tundra plants have developed many ways of surviving. Their low stature exploits a more favourable microclimate near the ground, while small, leathery leaves help lock in moisture. Many tundra mammals , birds and fish live there in summer, but migrate to warmer locations in search of food each autumn see Arctic Animals.
Not all abandon the region in winter see Animals in Winter. Foxes , hares , polar bears , ringed seals and birds such as the long-tailed jaeger remain.
Taken together, more than 75 mammals, bird species, 5 amphibians and 2 reptiles live in the tundra alongside 3, different kinds of arctic insects.
The earliest hunter-gatherers crossed the Bering land bridge into present-day Alaska see Beringia. Using sophisticated stone carved tools, they hunted large mammals and increased their population, spreading throughout the Arctic and the rest of the continent. New economic developments from resource extraction, shifting population demographics and climate change are driving rapid change throughout the region.
Rising temperatures are causing numerous tree and animal species to migrate north and into higher altitudes to find cooler climates. Such a scenario will put pressure on those living in the tundra to adapt to species once unfamiliar on the landscape. Ives and R. Barry, eds, Arctic and Alpine Environments Still, the tundra is usually a wet place because the low temperatures cause evaporation of water to be slow.
Much of the arctic has rain and fog in the summers, and water gathers in bogs and ponds. Vegetation in the tundra has adapted to the cold and the short growing season. Mosses, sedges, and lichens are common, while few trees grow in the tundra.
The trees that do manage to grow stay close to the ground so they are insulated by snow during the cold winters. The tundra is a treeless polar desert found in the high latitudes in the polar regions, primarily in Alaska, Canada, Russia, Greenland, Iceland, and Scandinavia, as well as sub-Antarctic islands. For most of the year, the tundra biome is a cold, frozen landscape. This biome has a short growing season, followed by harsh conditions that the plants and animals in the region need special adaptations to survive.
Tundra form in two distinct cold and dry regions. Humans have been part of the tundra ecosystem for thousands of years.
Originally nomadic, Alaska Natives have now settled in permanent villages and towns. As cold, dry tundras are threatened by warming from climate change, so are many of the plants and animals adapted to live there. Finally, low precipitation means there is not enough water to support trees. For most of the year, the tundra biome is a cold, frozen landscape.
This biome has a short growing season, followed by harsh conditions that the plants and animals in the region need special adaptations to survive. Tundra form in two distinct cold and dry regions.
Arctic tundra are found on high-latitude landmasses, above the Arctic Circle—in Alaska, Canada, Russia, Greenland, Iceland, and Scandinavia, for example—or on far southern regions, like Antarctica. Alpine tundra are located at very high elevations atop mountains, where overnight temperatures fall below freezing.
Tundra regions typically get less than 25 centimeters 10 inches of precipitation annually, which means these areas are also considered deserts. They have long, cold winters with high winds and average temperatures below freezing for six to ten months of the year. On average, only six to ten weeks of the year have sufficiently warm temperatures and long days for plant growth. The soil in the Arctic is largely permafrost or soil that remains frozen year-round, leaving only a thin surface layer of thawed soil in summer for plant roots to grow in.
Tundra soil is also scarce in many of the nutrients that plants need to grow. Instead, the tundra has patchy, low-to-ground vegetation consisting of small shrubs, grasses, mosses, sedges, and lichens, all of which are better adapted to withstand tundra conditions. Animals in the tundra are also adapted to extreme conditions, and they take advantage of the temporary explosion of plant and insect life in the short growing season.
Tundra wildlife includes small mammals—such as Norway lemmings Lemmus lemmus , arctic hares Lepis arcticus , and arctic ground squirrels Spermophilus parryii —and large mammals, such as caribou Rangifer tarandus. These animals build up stores of fat to sustain and insulate them through the winter.
They also have thick coats of fur for further insulation. Some save energy by hibernating during the long winter months.
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