Biomes 4

  • A Temperate rainforest biome is a type of rainforest biome occurring in a temperate climate.
  • To put it clearly, temperate rainforests experience vast amounts of rainfall, but feature a cooler average temperature compared to tropical rainforests.


Temperate Rainforests Biome

  • Temperate rainforests are located along some coasts in temperate zones.
  • The biggest temperate rainforests are located on the Pacific coast of North America.
  • They extend from Oregon to Alaska for about 1,200 miles.
  • Smaller temperate rainforests also exist.
  • They can be located on the southeast coast of Chile, South America.
  • A few other coastal strips exist that have temperate rainforests such as small parts in the U.K., New Zealand, Japan, South Australia and Norway.


  • Temperate rainforests are characterized by mild climates or temperatures.
  • Essentially, these areas do not experience extremely cold or extremely hot temperatures.
  • Temperate rainforests have two different seasons.
  • One season (winter) is quite long and wet, and the other (summer) is short, dry and foggy.
  • Throughout the long wet season, the temperature hardly falls below freezing point, which is 0°C and 32°F.
  • Throughout the short, dry and foggy season, the temperature hardly exceeds 27°C or 80°F.
  • This pretty much explains why this biome is referred to as temperate rainforest.
  • Also in summer, when it’s relatively dry, the weather is considerably cool as the fog supplies sufficient moisture to enable the rainforest to thrive.
  • Ideally, the fog contributes 18-30 cm (7-12 in) of precipitation every summer.
  • These biomes are so mild due to their closeness to the ocean on one side and mountain ranges on the other.
  • During winter months, the ocean water emits heat, leaving the coastal areas warmer and absorbs heat during summer months, leaving the coastal areas cooler.


  • Considering the word ‘’rain” is found in the word ‘’rainforest,” it tells you right off that this biome receives plenty of rainfall.
  • The average annual precipitation of a temperate rainforest biome is 200cm.
  • In much warmer areas, the average precipitation goes up to about 350 cm annually.


  • Temperate rainforests experience an extended growing season.
  • As opposed to tropical rainforests, temperate rainforests experience major seasonal changes.
  • Animals living in the temperate rainforest must develop adaptation to the ever-changing seasons.
  • Animals that are not able to adapt migrate in the winter.
  • Leaves of temperate rainforest trees change color and drop in the autumn.
  • They then regrow in spring.
  • The broad, flats leaves of temperate rainforests trees lose water fast.
  • Winter months normally leave the ground frozen, making it hard for them to absorb water.
  • The result is a massive drop off of leaves. The trees in this biome stay dormant and blossom again during spring.

Natural Vegetation

  • As opposed to tropical rainforests, temperate rainforests consist of only 2 layers of vegetation; the emergent layer and the canopy layer.
  • The understory layer and the forest floor consist of less vegetation.
  • The tallest trees in rainforests have their leaves typically approximately 15 to 30 centimeters from the ground, including a dense layer of small trees and shrubs beneath, at about 5 to 10 meters.
  • This is the real reason the soil in temperate rainforests receives a lot more light than their tropical counterparts.
  • The undergrowth in temperate rainforests is lush, consisting mainly of mosses, lichens, and ferns.
  • In the course of growth during spring, when the tree leaves have not wholly formed, there is a lot of light penetrating to the forest floor.
  • This aspect allows plant species to thrive on the ground, which explains why plant species that exist on the ground surface grow, flower and produce fruits before late summer.
  • Later on, sciophilus plants (plants species that love shade) begin to grow.
  • These plant species have developed immaculate mechanisms to harness and utilize low-light intensity, which gives them the ability to get by even when the vegetation or greenery grows and entirely covers the soil below.
  • The main kinds of trees found in the temperate rainforest biome include oaks, beeches, walnut trees, lime trees, sycamores, aspens, elms, tulip trees, and birches.

Animal Life

  • Compared to tropical rainforest biomes, temperate rainforest biomes harbor very few mammals due to the absence of a series of sophisticated layers and the fact that the vegetation is seasonal.
  • In summer months, the animal species of this ecosystem feed particularly on winged seeds and wall nuts that keep for a long duration.
  • Fruits produced by the rose tree, apple tree, gooseberry, Hawthorne, and others almost always ripen at the same time (during late summer) and are chiefly used in the course of summer for fat storage.
  • There is a huge diversity of life in temperate rainforest biomes.
  • Frogs, turtles, insects, birds, spiders and salamanders are just some of the animal varieties found here.
  • Bird species like cardinals, broad-winged hawks, pleated woodpeckers and snowy owls exist in this biome.
  • Some of the mammals present in this biome include raccoons, porcupines, red foxes, white-tailed deer, and opossums.
  • The arctic tundra is a vast, dry, rocky place that is noted for its lack of trees.
  • In fact, the word “tundra” comes from the Finnish word tunturi, meaning ‘treeless plain.’ One important characteristic of the tundra is the permafrost.
  • The word permafrost is short-form for the permanently frozen soil, which starts within a meter of the soil surface. In the winter almost all of the soil is frozen.
  • In the summer the soil near the surface thaws, but the permafrost at lower depths remain frozen.
  • The permafrost limits how far roots of plants can extend down into the soil.
  • It also is what prevents trees from growing.
  • The ground in the arctic tundra tends to be rocky and the soil has few nutrients.
  • This is because the decomposition rates of plants tends to be low.
  • Despite the lack of trees, this biome is still considered a major carbon sink as there are large amounts of organic matter found in deposits of peat and humus.
  • Peat is decayed sphagnum moss and humus is organic matter.


Arctic Tundra Biome

  • The arctic tundrabiome is the northernmost biome.
  • It covers the lands north of the Arctic Circle up to the polar ice cap.
  • It reaches as far south as the Hudson Bay area of Canada and the northern part of Iceland.
  • It covers approximately 11.5 million km2.
  • There is also an alpine tundra, which is found on mountains and Antarctic tundra, which is found on Antarctica and the surrounding Antarctic islands.


  • Due to its northern position, the arctic tundra has a very cold climate.
  • Temperatures range from 15.5 °C in summer to -60 °C in winter and mean temperatures are below 0°C for six to 10 months of the year.
  • Summers are also much shorter than the winters.
  • The northernmost part of this biome receives close to 24 hours of sunlight during parts of the summer.
  • And it receives close to 24 hours of darkness during parts of the winter.
  • Annual precipitation is around 150 to 250mm a year.
  • Most of this precipitation does not evaporate due to the low temperatures.
  • Rivers and lakes often form soil tends to be very soggy in the summer.

Natural Vegetation

  • Due to the cold climate and short growing season, most vegetation in the tundra tends to be herbaceous.
  • Examples of herbaceous plants found there include grasses, mosses such as reindeer mossliverwortsand lichens.
  • The few woody plants which live in the tundra, such as dwarf willows, tend to be short and spread across the ground.
  • This is an adaptation to the high winds that are common in this biome.
  • Plants in this biome also tend to go dormant during the long winters.
  • This means that they slow down their normal life functions.
  • Most of their biomass (mass of their parts) is below ground.
  • And they have relatively high growth rates in the short summers.

Animal Life

  • Many large mammals, such as caribou, polar bearsarctic foxes, and musk ox, are found in this biome.
  • There are also several smaller mammals, such as lemmingsand arctic hare which are prey to the larger mammals.
  • These prey animals have brown fur in the summer and white fur in the winter to help them camouflage with the changing landscape.
  • During the summer many migratory birds, such as loonssnow geeseand terns, come to the tundra to breed.
  • Although there is low insect biodiversity, the insects that live in the arctic tundra, such as mosquitoes, can have large populations.

Human Impacts & Conservation

  • In the past, humans have had relatively little impact on the arctic tundra.
  • Recently this has begun to change as more and more people have come to the north to extract various natural resources such as oil.
  • Climate changehas also begun to, and will continue to have a large impact on this biome.
  • Higher global temperatures are melting the sea-ice and permafrost.
  • This is altering and sometimes destroying the habitats of plants and animals.
  • In an effort to protect this unique biome, efforts to reduce human impacts are being undertaken.
  • This includes efforts to reduce levels of greenhouse gasesas well as the creation of protected areas where human interference and hunting are limited.
  • The Alpine tundra is located on high mountain regions in the world, for instance, the Swiss Alps.
  • As opposed to the Arctic Tundra, the Alpine Tundra are found away from the pole regions.
  • The word ‘Alpine’ is derived from the Alps which are high mountains that are found in Central Europe.
  • The characteristic of the Alpine is similar to polar tundra in that it has no trees, has annual temperatures that are recorded to be very low, and most animals migrate to these regions only during the productive summer periods.
  • However, the alpine tundra has more precipitation and higher annual average temperatures than the polar tundra.
  • The Alpine tundra is important because of the value of its biodiversity – it can be used for setting up undisturbed monitoring stations, can be used for recreational and leisure activities, and in the generation of mineral wealth.


Alpine Tundra Biome


  • The alpine tundra regions are located at any latitude in a high altitude area including some ecoregions having montane grasslands and shrublands.
  • There are regions having the large sections of the alpine tundra biome.
  • These are the Scottish Highland, The Himalayas, the Alps, The Rift Mountains of Africa, Tibetan Plateau, The Caucasus Mountains, the American Cordillera in both North regions and South American regions, and the Pyrenees and Carpathian Mountains found in Europe region.

Location on the mountain

  • High mountain summits, ridges and slopes found above the timberline are places where the Alpine Tundra is found.
  • Treeline can occur at higher altitude areas on regions that are warmer such as slopes that are facing the equator.
  • Meanwhile, the landscape of the region where they are located may be rocky, snowcapped mountain peaks, talus slopes, cliffs and in some cases flat topography with a gentle slope.


  • The Alpine Tundra traverses through many locations including across microclimates.
  • The treeline in the region is estimated to rise 75 meters 1° South from the latitude 70° to 50° North.
  • They are also estimated to rise 130 meters per 1° from 50° to 30° North and around 20° South.
  • In regions between 3,500 meters and 4,000 meters, the treelines are found to be roughly constant.

Geographical distribution

  • The distribution of the Alpine tundra is as a result of high altitude, high latitude, low temperatures that are below 25°F.
  • The low temperatures are important in maintaining the biome due to the fact that no trees can grow in the region.
  • The other factor that determines the distribution of this biome is the water availability.
  • The regions where the Alpine are found plants lack water which would have been essential for plant growth.
  • The snow which is permanently frozen does not provide any significant amount of water even during the summer period.



  • Average annual temperatures in the Alpine biome regions is similar to that of the Polar Regions.
  • The mean temperatures recorded at an altitude of 12,300 feet in July is 48°F.
  • The average temperatures that have been recorded in the months of January and December are around 9°F at the same altitude.
  • This shows that the variation of temperature in the Alpine regions is less extreme as seen in Arctic regions (Polar regions).
  • The variations in temperatures in this regions depend on latitude.
  • Alpine tundra regions in high altitude areas that are close to the arctic regions have almost the same annual temperature variations as those recorded in arctic tundra.
  • The sites found closer to the earth’s equator, for instance, Mt. Kilimanjaro located in Tanzania and the Ruwenzori Mountain in Uganda record little annual temperature variations.
  • However, the areas have extreme daily temperature variations.
  • For instance, in Mount Kenya at a height of 13,800 feet, the temperature during the day may rise to 60° F and in the same day may fall to 23° F.
  • This type of variation can pose danger to the crops that grow in this area.


  • Alpine regions experience high wind speeds that result in removal of the air that is close to the ground.
  • The air removed is warm and is absorbed by the vegetation that might be present.
  • The removal of the warm air exposes the vegetation and soil to extremely cold temperatures.
  • Also, the wind tends to carry with them the ice crystal that is destructive especially to sprouting plants around the region.
  • The direction of the wind is predicted depending on the pattern of the vegetation found around the Alpine biome borders.
  • For instance, in Sierra Nevada, California, the tundra vegetation is found at the lower elevations on the side facing the Pacific Ocean (western side) than the east side.
  • On the west side, the subalpine limit is around 10,500 feet and on the protected side is approximated to be at a height of 11,800 feet.


  • In Alpine regions, the air moving from the lowland or ocean regions is pushed up the mountain by the strong winds where it gets cooled as it moves up.
  • Cooled air has low water holding capacity, therefore, as this air rises its ability to hold water is reduced and the water content condenses to form clouds.
  • The cloud may then precipitate in form of rain droplets.
  • However, if the temperatures are extremely low, it falls in form of snow.
  • As a rule, the side that is facing the strong winds usually receives high levels of precipitation while the sides that are sheltered away from the windy side get the lowest.
  • Precipitation in Alpine biome increases with increase in altitude.
  • For instance in Boulder, Colorado, the annual precipitation is 395 mm at 5,250 feet while at 8,460 feet the annual average precipitation is around 540 mm.

 Low air pressure

  • The alpine biome is characterized by low air pressure and as a result, there are low amounts of oxygen.
  • For instance, at altitudes above 18,000 feet, the amount of oxygen found in the region is only half of that found in regions located at sea level.
  • Therefore, many animals such as the ibex and sheep cannot survive in such regions.
  • However, animals such as birds and some cold-blooded invertebrates can survive even in higher altitudes.

Natural Vegetation

Vegetation depending on altitude

  • The vegetation zones found in the Alpine are arranged depending on altitude rather than the latitude.
  • The vegetation in this biome stretch from Timberline at its base to the bare mountain peaks that has glacier or snow.
  • The Timberline is not continuous and has a ragged mixture of dwarf and twisted plants that manage to grow in this extremely harsh conditions.
  • In valleys that have shelter, the trees may mature more than those located in bare grounds.

Vegetation determined by soil

  • In some areas, the altitude does not determine the type of vegetation present.
  • Areas such as the Southern Appalachian Mountains, Montana, have grassy “balds” due to shallow soils that cannot support tree growth in this regions.
  • Also, the cold associated with this regions also play a major role in determining the type of crop that grows in the biome.

Vegetation Zones

  • Kenya in East Africa has different vegetation zones that are found at different heights.
  • The regions close to the equator have tropical savannah vegetation and forest.
  • As the height increases the vegetation change and gives way to a temperate forest that is made up of bamboo.
  • The bamboo forest gives way to the shrub zone.
  • The Alpine Tundra biome is located at heights above 12,000 feet.
  • And above these regions is the permanent snow.

Animal Life

  • As stated earlier, the Alpine tundra is located in many different regions around the world and at these regions have different climatic and microclimatic patterns.
  • Thus, there are no common and specific animals that are associated with the Alpine biome.
  • Nonetheless, there are a few animals that prefer in living in this regions such as birds that migrate from different regions, invertebrates and mammals.


  • There are a significant number of animals that live in the Alpine tundra regions despite the harsh conditions.
  • The invertebrates have the disadvantages of being cold-blooded as their temperatures are determined by the surrounding environment.
  • Their activities are limited especially during extremely cold temperatures as experienced in winter.
  • These animals have to adapt by feeding on insects and a few plants that are available in the region.
  • Examples of invertebrates living in the region are the springtails, a group of delicious mammals.


The availability of insects and berries have made the biome to be a region of migration of birds during summers in areas located near the poles. Birds that do not feed on seafood search for food on the mountainous tundra.


  • There are different types of mammals that traverse the alpine tundra region in search of food.
  • Some of the animals that are associated with the Alpine Tundra regions are the Mountain goat, Kea, sheep, yak, pika, marmot, chinchilla and bighorn sheep.