Tundra Biome

By: Esther Kim & Mae LeskoAP Biology

7/8 B

Where is a Tundra Biome found?

• Arctic Tundra is found in the NORTHERN HEMISPHERE surrounding the North Pole

• Alpine Tundra is located on the top of mountains, where trees cannot grow because of the high altitude on the mountains.

Notice how plants can grow here

But nothing is able to grow on the top of the mountains

What makes up a Tundra Biome?

• Tundra Biomes typically have the following factors:–Very cold climate (average yearly

temperature ranges from -30°F - 20°F)–Low biotic diversity –Permafrost–Short reproduction seasons–Simple vegetation structure

Arctic Tundra Climate• Long winters, short summers• Average winter temperature: -30° F• Average summer temperature: 37-54° F• Only exposed to 6 months of sunlight a year (sun

shines 24 hours a day during the summer)• High winds -> causes “white outs” (windstorm

kicks up snow)• Very little precipitation – Yearly precipitation = 6 to 10inches of snow

Alpine Tundra Climate• Low temperatures, but slightly

warmer than the artic• Rain and fog in the summer

months -> collects in bogs• Alpine Tundra is mostly always

wet because the low temperatures stalls the evaporation of water

Low Biotic Diversity• Animals that are able to adapt to

extremely long winters, short mating seasons, and the rocky soil

• Because there are few animals that have adapted to the biome, the biotic diversity in the tundra is low

• The same species exist there from years prior

Snowy Owl

Polar Bear

Reindeer

Penguins

Permafrost• Not much plant wildlife can grow in

the soil of the tundra because of the permafrost below the first rocky layer of soil

• The subsoil, consisting of gravel, is permanently frozen and 2000 feet thick, known as permafrost

• Plants that grow in the tundra are adapted to cold temperatures, strong winds, and disturbances to the soil– Plants must be small and close to the

ground to avoid resisting the winds– Fixated in a clumped pattern– Reproduce by budding and division

rather than sexually through pollination

Abiotic factors of the Tundra

• Strong Winds• Little precipitation (rainfall)• Short summer days• Very long and cold winters• Poor soil• Permafrost

• The abiotic factors cause:– Animals to adapt to short reproduction

seasons– Plants to adapt to harsh winds,

temperatures, and growing in the permafrost and soil

– Very long winters cause a short growing period of only 180 days

– Very little diversity among plant species and animal species throughout a Tundra Biome

Biotic factors of the Tundra

• Clumped spacing amongst plants and animals

• Tundra is treeless because of the inadequate growing conditions for tall plants

• Low biodiversity amongst animals: snowy owls, reindeer, polar bears, white foxes, lemmings, arctic hares, penguins, wolverines, caribou, migrating birds, mosquitoes, and black flies.

Limiting Factors of the Tundra

• Density-dependent factors:–Lack of heat–Low temperatures–Long winter–High altitude –Poor soil

• Density-Independent factors:–Shortage of food–Scarcity of shelter

Where is everybody?

Organisms within the Tundra

• Producers:– Lichens (Reindeer moss)– Dwarf-trees– Bear-berry– Sedges (cotton grass)

Lichen (Reindeer Moss)• Main food source for caribou/reindeer• Have no vascular tissue or seeds

Dwarf Trees

• Only tree that is able to grow in tundra because of its short size

Bear-berry• Berry is consumed by bears• Berries are can also be gathered

by other species for food• Leaves are used as herbal

medicine

Sedges (cotton grass)• Tundra winds help

disperse the seeds• Acts as food for

migrating geese• Caribou calves also

eat cotton grass togrow quickly

Consumers of the Tundra

• Primary ConsumersCaribou

Lemming

• Secondary ConsumersSnowy owl

Arctic fox

• Tertiary Consumers

Arctic Wolf

Polar Bear

The Food Web of the Tundra Biome

• Tertiary Consumer: These organisms gain nourishment through consuming other meat eating organisms.

• Secondary Consumers: These organisms gain nourishment though consuming herbivorous organisms.

• Primary Consumers: These organisms feed directly on the producers who gain their energy from the sun.

• Decomposers: These organisms feed on other dead organisms. They break the dead matter down to release chemical energy back into the soil for re use.

• Producers: These organisms gain energy from the sun.

Population Size

• According to studies, the population size of polar bears is around 800 to 1200 in Laptev Sea.

• The polar bears, being the endangered species, are the limited organisms of the

Polar Bears• Polar bear survivorship can be represented

by the type I survivorship curve.• They reproduce fewer offspring and take

care of them until they are strong enough to take care of themselves, giving them a longer life span.

• Most polar bears die of old age, giving them a stable population size.

Predator-prey Relationships

• Predators eat their prey, decreasing the number of prey.

• This also causes the number of predators to go down.

• With less predators, the prey is able to reproduce and fill the missing numbers.

• The predator does them same and the cycle repeats itself.

• Some examples of predator-prey relation ships are :- Lynx and snowshoe hare

- Polar bears and seals

As the number of lynx increases, the number of hares decrease.

Maintaining Population Control

• In the predator-prey relationships, the prey and the predator both help balance the population size. When the predator hunts most of the prey, resources become scarce for the predator therefore the population size of the predator also declines.

• After the predators decrease in number, the prey is able to increase in size once again and once there are enough the predators start the cycle once again.

Examples of Defense Mechanism• Mutualism: The reindeer lichen is made up of a specific alga and

a specific fungus, the two work together to form one plant.• Parasitism: In the tundra ticks and tapeworms can be found in

many arctic animals such as caribou, muskoxen, arctic foxes and wolves.

• Commensalism: The fox follows a caribou, which clears the snow to find lichens, to hunt subnivien mammals.

• Competition: There isn’t much competition in the tundra because not many organisms can survive the harsh climate. However, the plants that are able to grow compete for what fertile ground is left.

• Predation: Polar bears generally hunt seals, however they settle for whales that have gotten washed ashore. When there are less products, then the primary consumers suffer. This causes the secondary consumers to suffer and the tertiary consumers also.

The Energy or Biomass Pyramid

• The Energy or biomass pyramid shows the amount of energy that is transferred from an animal.

• If an organism consumes something that is in the bottom of the pyramid, it has consumed the most energy.

• When an organism feeds on something no at the bottom of the pyramid, they are getting energy that was transferred from something they consumed. Therefore you are receiving less energy than feeding on something that has gained its energy directly from the sun.

Disturbances• Human interaction:Pollution

- Greenhouse gases- Littering- Releasing pollutants through the car

* All three reasons are indicative of Global Warming.

• As global warming occurs, winters in NJ become warmer and summers become hotter. However, in a tundra, the warmer weather will melt the glaciers and the snow that covers it.

• The temperature rises 1 degree Fahrenheit every year globally. Though to some this may seem a negligible amount it is not. The ice caps in tundra biomes are devastated by this 1 degree increase because the ice starts to melt away, disturbing the biome.

• It is projected that in 50 to a 100 years the majority of the tundra will be gone due to global warming.