Transcript Document
About the Tundra… Temperature: Average Yearly Temperature:16° F Average Winter Temperature: -10° F Summer Temperatures: 35-55 ° F Precipitation: Annual precipitation, including melting snow, is 18 inches Solar Insolation: Tundra does not have traditional seasons, only a lengthy winter and a brief mild season. Limiting Factors: Plant growth is hampered by the layer of permafrost, or permanently frozen subsoil. Species Diversity About 1700 types of plants in the arctic tundra Vegetation: Grasses, mosses, lichens, sedges, shrubs, trees include birches and willows Mammals: Caribou, arctic foxes and hares, polar bears, lemmings, porcupines, mountain goats and elk in the alpine tundra Birds: Snowy owls, falcons, snow geese, tundra swans, ptarmigans, ravens Food Chain of the Tundra: Tundra Grasses Sun Arctic Fox Lemming Polar Bear Unique Facts about the Tundra: There are two types of tundra: arctic tundra and alpine tundra Arctic tundra is more common and is located from the north pole to the forests of the taiga Alpine tundra is located in high elevations Throughout the winter, the tundra gets only a few hours of sunlight. In the summer, the tundra can get up to an entire day of sun. The Tundra By T. Cohen Tundra Biome Information • Temperature : -40°C to 18°C • Precipitation: 150 to 250 mm of rain per year • Solar Insulation – Winters – long, dark, and cold • Mean temperatures below 0°C for 6 to 10 months of the year – Summers – Short season, Long days • Top layer of soil thaws a few inches down • Provides a growing surface for the roots of vegetation • Rain and fog – water gathers in bogs and ponds • Limiting Factors: low temperatures, the little water is frozen, permafrost affects vegetation, animal enzymes cannot function in cold Tundra Species Diversity • Vegetation – Permafrost prevents drainage of excess moisture – Growing season is short and can last up to 60 days – Low diversity – Few plants could survive extreme temperatures, lack of water, and low soil – lichens, mosses, sedges, perennial forbs, and dwarfed shrubs, heaths, birches and willows – Trees that do manage to grow stay close to the ground • Insulated by snow during the cold winters Tundra Species Diversity • Animal Life – lower diversity due to extreme conditions – Result: Residents adapt to environment • Morphological adaptations – large, compact bodies – thick Insulating cover of feathers or fur – pelage and plumage that turns white in winter, brown in summer • Physiological adaptations – ability to accumulate thick deposits of fat during the short growing season – Fat acts as insulation; store of energy for use during the winter, when animal species remain active. • Population adaptations – cyclical fluctuations in population size – Predator populations and plant populations respond in kind to the peaks and crashes of the herbivore populations. Food Chain Tundra food chains are short and highly susceptible to changes Reindeer Lichen Woodland Caribou Polar Bear Interesting facts • Permafrost – temperatures are so cold that there is a layer of permanently frozen ground below the surface (6 in.) • The Precipitation levels - 150 to 250 mm of rain/yr – Includes melted snow – Less than most deserts • Still usually wet though: the low temperatures cause evaporation of water to be slow • Snowfall is actually advantageous to plant and animal life as it provides an insulating layer on the ground surface