Tundra ecosystems are treeless regions found in the Arctic and on the tops of mountains, where the climate is cold and windy, and rainfall is scant. Tundra lands are covered with snow for much of the year, but summer brings bursts of wildflowers.
Mountain goats, sheep, marmots, and birds live in mountain—or alpine—tundra and feed on the low-lying plants and insects. Hardy flora like cushion plants survive in the mountain zones by growing in rock depressions, where it is warmer and they are sheltered from the wind. Alpine tundras exist worldwide at altitudes above the mountain tree line. The Arctic tundra, where the average temperature is to 20 degrees Fahrenheit to -6 degrees Celsius , supports a variety of animal species, including Arctic foxes , polar bears , gray wolves , caribou , snow geese , and musk oxen.
The summer growing season is just 50 to 60 days, when the sun shines up to 24 hours a day. The relatively few species of plants and animals that live in the harsh conditions of the tundra are essentially clinging to life. They are highly vulnerable to environmental stresses like reduced snow cover and warmer temperatures brought on by global warming.
The Arctic tundra is changing dramatically due to global warming , a term that falls within a wider range of trends scientists now prefer to call climate change. The impacts in this region are broad and somewhat unpredictable.
Animals that are typically found further south, like the red fox , are moving north onto the tundra. This means the red fox is now competing with the Arctic fox for food and territory, and the long-term impact on the sensitive Arctic fox is unknown. Other tundra denizens, such as the wolf spider, are growing bigger and thriving. Shrubs are getting taller , contributing to declines in the sensitive groups of lichen that caribou and other species depend on for food.
Lakes and ponds are evaporating or draining away. The Arctic's permafrost, the literal foundation for much of the region's unique ecosystem, is deteriorating with the warmer global climate.
Permafrost is a layer of frozen soil and dead plants that extends some 1, feet meters below the surface. In much of the Arctic, it is frozen year-round. In the southern regions of the Arctic, the surface layer above the permafrost melts during the summer, and this forms bogs and shallow lakes that invite an explosion of animal life. Insects swarm around the bogs, and millions of migrating birds come to feed on them. With global warming, the fall freeze comes later— in some places recently, not at all —and more of the permafrost is melting in the southern Arctic.
They also have thick coats of fur for further insulation. Some save energy by hibernating during the long winter months. Others migrate to warmer climes during winter. Many birds also migrate into the tundra during the growing season to feed, mate, and nest. Atop the food chain are tundra carnivores, such as arctic foxes Vulpes lagopus , arctic wolves Canis lupus , snowy owls Bubo scandiaca , and polar bears Ursus maritimus , which move into the tundra during the summer when prey is plentiful and their usual hunting grounds on sea ice diminish.
Many animals, both predator and prey, develop white fur or feathers in the winter months for camouflage in ice and snow. Tundra insects have also developed adaptations for the cold; mosquitoes Aedes nigripes , for example, have a chemical compound that acts as antifreeze, lowering the freezing temperature in their bodily fluids.
Though the tundra is remote, it is increasingly threatened as people encroach on it to build or drill for oil, for example. Perhaps the greatest danger, however, comes from climate change. Warming temperatures could disrupt the cold tundra biome and the life in it, as well as thaw its underlying permafrost, releasing greenhouse gases that would further accelerate global warming. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit.
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If no button appears, you cannot download or save the media. Text on this page is printable and can be used according to our Terms of Service. Any interactives on this page can only be played while you are visiting our website. You cannot download interactives. The two major nutrients are nitrogen and phosphorus. Nitrogen is created by biological fixation, and phosphorus is created by precipitation. Arctic tundra is located in the northern hemisphere, encircling the north pole and extending south to the coniferous forests of the taiga.
The arctic is known for its cold, desert-like conditions. The growing season ranges from 50 to 60 days. Rainfall may vary in different regions of the arctic. Yearly precipitation, including melting snow, is 15 to 25 cm 6 to 10 inches.
Soil is formed slowly. A layer of permanently frozen subsoil called permafrost exists, consisting mostly of gravel and finer material.
When water saturates the upper surface, bogs and ponds may form, providing moisture for plants. There are no deep root systems in the vegetation of the arctic tundra, however, there are still a wide variety of plants that are able to resist the cold climate. There are about 1, kinds of plants in the arctic and subarctic, and these include:. All of the plants are adapted to sweeping winds and disturbances of the soil. Plants are short and group together to resist the cold temperatures and are protected by the snow during the winter.
They can carry out photosynthesis at low temperatures and low light intensities. The growing seasons are short and most plants reproduce by budding and division rather than sexually by flowering. The fauna in the arctic is also diverse:.
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