(ECO) Biomes Chart: Tundra and Taiga Lesson

Biomes Chart: Tundra and Taiga Lesson

You will need your Biome Chart for this lesson. 

Complete the chart for each Biome in this module.  

These notes are useful for studying and can be a valuable resource for upcoming Biome assignments.

 

Tundra and Taiga Biome

Did you know that the Arctic Tundra is the world's youngest biome? It was formed 10,000 years ago. The tundra is a vast and treeless land. It covers about 20% of the Earth's surface while circumnavigating the North Pole. It is usually very cold and the land is pretty stark. The tundra biome is most often located in the Northern Hemisphere. Small tundra-like areas do exist in Antarctica within the Southern Hemisphere. It is much colder than the Arctic because the ground is always covered with snow and ice.

Tundra comes from the Finnish word "tunturia", which means a barren land. The ground is permanently frozen 10 inches to 3 feet (25 to 100 cm) down so that trees can't grow there. The bare and sometimes rocky ground can only support low growing plants like mosses, heaths, and lichen. The tundra is basically like a desert when it comes to precipitation. Only about 6 - 10 inches of precipitation fall each year. Below the soil is the tundra's permafrost, a permanently frozen layer of earth. During the short summers the top layer of soil may thaw just long enough to let plants grow and reproduce. Since it can't sink into the ground, water from melting permafrost and snow forms lakes, bogs, and marshes each summer. These bodies of water breed thousands of insects that attract many migrating birds.

There is barely any vegetation in the tundra. There is about 1,700 different species of plants which isn't very much. These are mostly shrubs, sedges, mosses, lichens and grasses. There are about 400 varieties of flowers. The growing season is only about 50 to 60 days long. There are no trees, except for some birches in the lower latitudes. The ground is always frozen beneath the top layer of soil, so trees can't send their roots down. Willows do grow on some parts of the tundra but only as low carpets about 3 inches (8 cm) high. Most plants grow in a dense mat of roots that has developed over thousands of years. The soil is very low in nutrients and minerals, except where animal droppings fertilize the soil.

We will learn about seasonal environmental conditions in the Antarctic and their influence on the southern polar ecosystem. Watching the video below will allow us to investigate the variety of organisms that inhabit this unique ecosystem during summer and winter. Additional information reveals how significant factors, including food supply and sea ice, respond to changing climate conditions. While using this interactive, look for examples of the differences exhibited in summer and winter in the Antarctic ecosystem. What are some of the adaptations seen in animals that allow them to survive in the rigorous environmental conditions found at the poles? Which marine organisms are most reliant on sea ice and why? Which are least reliant and why?

 

 

What might happen to the Arctic ecosystem should different members of the food web vanish from it? What factors might cause this to happen?

The intriguing video shown below visits northeast Alaska, taking viewers on a discovery tour of the arctic tundra biome. The program focuses on the various species of plants and animals and how they adapt to the harsh and frigid climate of this treeless and flat land on top of the world. We learn that the arctic tundra biome is a beautiful and often barren place, where winter lasts an incredible ten months and summer is but ten short weeks. Winter temperatures can dip down to minus 70 degrees in this environment. In the summer, daylight lasts 24 hours a day and temperatures climb to as high as 75 degrees. While watching we will learn more about permafrost and how its existence influences the living community of this ecosystem. Pay close attention to the cyclic nature of animal life in this biome, where so much depends on the tiny brown lemming, a vital link in the tundra's local food chain. The video is approximately 17 minutes long. Pause the video when necessary to make notes. While watching the video, listen for more information or details about the answers to the following questions:

• What characteristics make the arctic tundra biome unique?
• Where is the arctic tundra biome found?
• What is permafrost and how does it affect life on the arctic tundra?
• Describe the types of plants, which grow on the arctic tundra.
• How do plants adapt to the adverse conditions of the land?
• Does photosynthesis take place in the arctic tundra biome? If so, how does it occur?
• What different types of mammals live in the arctic tundra biome?
• What are some types of birds that live on the arctic tundra? Why do they migrate?
• What adaptation strategy do mosquitoes use to survive in the Arctic tundra?

 

 

 

Taiga is the Russian word for forest. The taiga is located near the top of the world, just below the tundra biome. The winters in the taiga are very cold with only snowfall. The summers are warm, rainy, and humid. A lot of coniferous trees grow in the taiga. The taiga doesn't have as many plant and animal species as the tropical rainforest biome. It does have millions of insects in the summertime. Birds migrate there every year to nest and feed.

The average temperature is below freezing for six months out of the year. The winter temperature range is -54 to -1° C (-65 to 30° F). The winters, as you can see, are really cold, with lots of snow. The temperature in the summer can get as low as -7° C (20° F). The high in summer can be 21° C (70° F). The summers are also very short with about 50 to 100 frost-free days. The total precipitation in a year is 30 - 85 cm (12 - 33 in). Most of the precipitation in the taiga falls as rain in the summer.  The spring and autumn are so short that you hardly know they exist. It is either hot and humid or very cold in the taiga.

There are not a lot of species of plants in the taiga because of the harsh conditions. Not many plants can survive the extreme cold of the taiga winter. There are some lichens and mosses, but most plants are coniferous trees like pine, white spruce, and hemlock.

Coniferous trees are also known as evergreens. They have long, thin waxy needles. The wax gives them some protection from freezing temperatures and from drying out. Evergreens don't loose their leaves in the winter like deciduous trees. They keep their needles all year long. This is so they can start photosynthesis as soon as the weather gets warm. The dark color of evergreen needles allows them to absorb heat from the sun and also helps them start photosynthesis early.

Evergreens in the taiga tend to be thin and grow close together. This gives them protection from the cold and wind. Evergreens also are usually shaped like an upside down cone to protects the branches from breaking under the weight of all that snow. The snow slides right off the slanted branches.

The taiga is susceptible to many wildfires. Trees have adapted by growing thick bark. The fires will burn away the upper canopy of the trees and let sunlight reach the ground. New plants will grow and provide food for animals that once could not live there, because there were only evergreen trees.

Animals of the taiga tend to be predators like the lynx and members of the weasel family like wolverines, bobcat, minks and ermine. They hunt herbivores like snowshoe rabbits, red squirrels and voles. Red deer, elk, and moose can be found in regions of the taiga where more deciduous trees grow.

Many insect eating birds come to the taiga to breed. They leave when the breeding season is over. Seed eaters like finches and sparrows, and omnivorous birds like crows stay all year long.

 

In the video clip from Biomes: Our Earth's Major Life Zones shown below, the taiga biome being discussed (a northern forest) is dominated by conifers. The climate in this biome includes long cold winters with a short summer growing season.

 

 

In the BBC Planet Earth video segment  Life in the Taiga Forest  shown below, we learn more about how conifer trees provide much for the inhabitants of the cold taiga forest. Some use these trees for food, while others use them for shelter, and still others use them to stalk their prey. Note how the animals shown in the video have adapted so as to survive in this environment.

 

 

 

Taiga and Tundra Ecology Term Practice

Complete the following review activity.

 

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