Tundra+period+8

**Tundra period 8**
[] **Facts/characteristics of the Biome:** In the **tundra**, conditions are cold, with an annual average **temperature** less than **5� C**, and **precipitation** (mostly in the form of snow) less than **100** **mm** per year (see figure at right). The summer is brief, with temperatures above freezing lasting for only a few weeks at most. However, this "warm" summer coincides with periods of almost 2**4 hour daylight**, so plant growth can be explosive.

The tundra is a bleak and treeless place. It is cold through all months of the year Summer is a brief period of milder climates when the sun shines almost 24 hours a day. It has been called "the land of the midnight sun". But even the sun can't warm the tundra much. The short summer lasts only 6 to 10 weeks. It never gets any warmer than 45 or 50° F. The warmer weather causes a layer of permafrost, ice that never goes away in the ground, to melt, creating bogs and shallow lakes that don't drain. They breed stinging insects, which make life even in the summer miserable for the inhabitants of the tundra. The wind blows constantly, whipping around the small plants. During the long winter months the sun barely rises and it is dark for most of the day. Bitter cold winds scud across the barren snowscape, exposing high plateaus to barren ground. Winter temperatures don't reach above 20° F and average -6 the tundra is an extreme weather biome. The tundra seems like a wet and soggy place because the precipitation that falls evaporates slowly, and because of the poor drainage caused by the permafrost. You can find the tundra climate in Köppen's E climate category. The Estands for ice climates. The average temperature of the warmest month is below 50° F. The tundra climate spans from most of Greenland to parts of Alaska, northern Canada, and northern Russia. The latitudinal range is 75° N to 60° N. Tundra climates can be found on the coastal areas of the arctic. The ocean water keeps the climate from falling to the extreme temperatures found in the interior of the continents.

**Location of the Biome**: The map below shows the **tundra** spreading across the northern hemisphere. Tundra is largely restricted to the **northern hemisphere**; there simply is no comparable land mass in the southern hemisphere with the appropriate climate. The areas of the southern hemisphere at high enough latitudes is small, and these areas have their temperatures moderated by the proximity of surrounding oceans. Parts of **Greenland** extend north far enough that the tundra is replaced by snow and ice; in contrast Canadian and Russian islands at these latitudes are again influenced by the surrounding oceans and may thus exhibit tundra conditions. It should be noted that a similar habitat, alpine tundra, exists in mountains of the alpine biome.

**Consumers/Animals living in the biome** :



Tundra is described as an area where levels of subsoil beneath the surface of the earth are permanently frozen. This soil is referred to as __ permafrost __. The level of earth above the permafrost will thaw in the short summer allowing plants to grow. This level will then freeze again in the winter and most of the plants will go dormant. The permafrost makes it difficult or impossible for trees to root down into the ground, so one of the characteristics of  tundra is that it is often treeless and the land appears barren. Another characteristic of tundra is that it, like deserts, receives little precipitation. Tundra will also reach extremely frigid temperatures, especially in the winter when it receives little to no sunlight. Tundra has two variations, Arctic Tundra and Alpine Tundra. Arctic Tundra can be found near or north of the Arctic circle around the north pole.* Alpine Tundra can be found at various latitudes on earth but is located at high altitudes on mountains where trees do not grow.

Animals that live in the tundra have special adaptations that allow them to survive the extreme temperatures and conditions that are present in a tundra. A good example of an animal with special adaptations is the Arctic Fox. The Arctic Fox has short ears and a short, round body with a thick coat to minimize the amount of skin exposed to the frigid air. There is a low amount of biodiversity in the tundra so fluctuations in one animal population will effect populations in another. An example of this would be that if in a certain year there is a lower amount of Lemmings than usual, then the population of Snowy Owls, who feed mostly on Lemmings, will also decrease.

There are several threats to the populations of animals that live in the tundra. Mining and oil drilling are increasing habitat loss, as well as human habitations moving farther north. Global warming could be one of the largest threats to this ecosystem. As global warming melts more of the permafrost soil the very delicate balance of plant and animal life in the tundra is threatened.

**Producers/Plants living in the biome:** Close to 2.5 billion years ago, the earth's surface and atmosphere were stable enough to support primitive life. Single-cell organisms began to develop in the seas that covered the planet. A simple organism known as blue-green algae appeared and spread across the seas. Blue-green algae used sunlight and water to make food, and in the process, created oxygen. As the blue-green algae grew in the earth's seas, they began to fill the atmosphere with oxygen. The oxygen that blue-green algae produced made it possible for other types of organisms to develop. Plants play the most important part in the cycle of nature. Without plants, there could be no life on Earth. They are the primary producers that sustain all other life forms. This is so because plants are the only organisms that can make their own food. Animals, incapable of making their own food, depend directly or indirectly on plants for their supply of food. All animals and the foods they eat can be traced back to plants. The oxygen we breathe comes from plants. Through photosynthesis, plants take energy from the sun, carbon dioxide from the air, and water and minerals from the soil. They then give off water and oxygen. Animals and other non-producers take part in this cycle through respiration. Respiration is the process where oxygen is used by organisms to release energy from food, and carbon dioxide is given off. The cycles of photosynthesis and respiration help maintain the earth's natural balance of oxygen, carbon dioxide, and water. Leaves are the main food-making part of most plants. They capture energy from sunlight, and turn water and carbon dioxide into sugar and starch. This sugar and starch becomes the food that provides plants with energy to grow, to produce flowers and seeds, and carry on their other life processes. Plant Facts Scientists believe there are over 260,000 species of plants. Some plants are so small they can barely be seen. Others are taller than people or animals. One of the largest living plants on the earth are the sequoia trees of California. Some stand over 290 feet (88 meters) high and measure over 30 feet (9 meters) wide. Certain characteristics of plants set them apart from other living things. Both plants and animals are complex organisms that are made up of many types of cells, but plant cells have thick, rigid walls that consist of a material called cellulose. Animal cells do not have this material. The cellulose enables plants to stand upright without the aid of an internal or external skeleton. Plants and Their Environment Plants require a reasonable level of heat to grow. The most favorable temperature at which photosynthesis takes place ranges from near freezing to 20 to 25° C (70 to 80° F). The rates of photosynthesis and respiration increase with rising temperatures. Any temperatures above or below these levels limit plant growth. The climate of a region determines what types of plants can survive in that region. A plant's environment is made up of many factors. One of the most important is the weather--sunlight, temperature, and precipitation (rain, melted snow, and other moisture). Soil and other plants and animals that live in the same area are also included in the environment of a plant. All these factors form what is called a natural community. No two natural communities are exactly alike, but many resemble one another more than they differ. Botanists divide the world into biomes--natural communities of plants, animals, and other organisms. Medicine Plants provide many useful drugs. Some of these plants have been used as medicines for hundreds of years. The bark of the cinchona tree was used 400 years ago to reduce fever. It is still used to make quinine, a drug used to treat malaria and other diseases. Another drug, called digitalis, is used in treating heart disease. It is made from the dried leaves of the purple foxglove plant. The roots of the Mexican yam are used in producing cortisone, a drug useful in treating arthritis and a number of other diseases. || ** Dominant (keystone) species in the biome: **
 * The Importance of Plants

Keystone species are usually top predators. By definition, a keystone species is a species that has a much larger impact on an ecosystem than their relative biomass would suggest. The removal of a keystone species usually leads to extreme changes in the entire ecosystem.

Some examples of keystone species that have been removed from ecosystems are sea otters on the west coast of North America, and wolves in Yellowstone Park. Sometimes it's hard to confirm which species is a keystone species until after it has been removed. None of the species in your list has been removed from the tundra (thankfully), so you will have to make an educated guess.

**Average Temperature Range for the biome:**



** The Tundra has extremely cold temperatures. The summer high is around 40 degrees F. The coldest winter temperature gets down to -25 degrees F. That's much colder than any Biome in the world. Sometimes as few as 55 days per year have a mean temperature higher than 32 F (0 C). The average annual temperature is only 10 to 20F (-12C to -6C). **

** Annual Precipiation for the biome: ** According to Blue Planet Biomes, the climate of the tundra is extremely dry with precipitation levels similar to those of tropical deserts. The average precipitation, including melting snow, in the tundra is between 6 and 10 inches per year. Coupled with strong drying winds, the annual precipitation makes the tundra an area of extreme weather. Melting snow blown from high plateaus collects in the valleys of the tundra and melts slowly to leave the ground soggy despite the dry climate.