Presentation on theme: "Also known as the Boreal, Evergreen Forest, or Coniferous Forest."— Presentation transcript:
Also known as the Boreal, Evergreen Forest, or Coniferous Forest
The taiga biome is dominated by polar and arctic air masses. Canada and Siberia are two sources of these air masses. There is no counterpart in the southern hemisphere, because of far less land mass. Latitude in the northern hemisphere ranges between 50°N and 70°N A typical climograph in the Taiga may look like this:
Cold temperatures and food shortages make living in the Taiga very difficult. The taiga is the largest land biome on Earth, covering about 50 million acres of land. This is about 17% of the Earth's land area. Taiga is a Russian word for marshy pine forest.
Taiga is the largest “terrestrial” biome on Earth. Tell me one fact about the Tundra that is unique to this biome. How does rainfall in the Tundra compare to rainfall in the Taiga?
The taiga is characterized by a cold, harsh climate, a low rate of precipitation (snow and rain), and short growing season. Trees are approaching the limits of their physical tolerance for extreme cold in such a climate. There are long, wickedly cold winters, and a short summer growing season, which produces relatively short trees High winds and the brittleness of the branches in winter mean that the trees take on this odd look: Often really short branches that make the trees look like fuzzy telephone poles.
Trees of the Taiga tend to be conifers. Conifers produce cones in late winter or early fall. These cones contain the tree’s seeds. Once the seeds ripen, the cone dries up and the seed falls out. Even though a lot of sunshine can get through the trees in this situation, there is still pretty sparse undergrowth, and the litter is dense The leaf litter is too tough and resinous to rot in the very short warm season. It can take up to two years to produce a mature seed. Squirrels like to feed on these seeds. What does manage to rot, adds a tannin (tannic acid) from the needles to the soil, making the soil quite acidic.
With a thick carpet of needles, dead branches, and frozen ground for a great part of the year, decay proceeds very slowly. The litter stifles new growth by cutting off seedlings from soil contact (if they're on top of the litter when they germinate) or from sunshine (if they're on the ground below the litter). Because of this, the trees are generally widely spaced, and not dense as they would be in a more southern biome.
When deciduous trees grow, they change the soils, making them a little more basic instead of acidic, which makes it easier for baby conifers to re-establish themselves. The big hazard in the Taiga is huge fires. Fires clear the forest floor and allow for sun- loving species, such as deciduous aspens, some alders, and birches to flourish. The short-lived deciduous trees die because of the harsh conditions, and the baby conifers replace them again in the forest.
How would trees in the Tundra differ from trees in the Taiga? If low-growing plants are supported in the polar regions of the southern hemisphere, in Antarctica, where it is colder…why then are they NOT supported in the polar northern hemisphere? Which biome could you most compare the Tundra to, in terms of precipitation? Why do flowering plants do so well for such a short period of time in the Tundra?
Life in the taiga can be cold and dreary for animals as well as plants. Snow, cold, and a scarcity of food make life very difficult, especially in the winter. Some taiga animals migrate south, others go into hibernation, while others simply cope with the environment. The European Red Squirrel is adapted to the Taiga by the food it eats. Their preferred food is the seeds from conifer cones. Their brood nests are high in the branches of the conifers, which also double as their winter quarters.
The lynx is perfectly adapted to the Taiga. Its fur changes according to the season and environment the cat is in. Their brood of young is usually born in the spring, and they remain with the mother through their first winter. The moose is adapted by eating the woody parts of conifers in the winter, and the fleshy aquatic plants it has access to in the summer.
This “varying” hare has a dark brown coat in the summer, and bright white in the winter. Camouflage!!!!! They produce more offspring during years when food is plentiful, and fewer when there is less food. The wolverine exhibits a phenomenon known as “delayed implantation”. (embryonic diapause) drive male pup out delayed sexual maturity mostly carnivorous
Animals in both the Tundra and Taiga hibernate during the harshest time of year. How would hibernation in the Taiga differ from hibernation in the Tundra? Describe how predators in the Tundra and Taiga use camouflage as an adaptation. Describe how prey organisms in the Tundra and Taiga use camouflage as an adaptation. What organisms in the Tundra have humans tried to control with pesticides, and why are they so abundant? Why is the Tundra more susceptible (or fragile) than the Taiga?