BIOMES

What is a Biome? A large area with distinct climate, plant and animal life; climate factors – sun, rain, topography; climate determines life.

DesertsDescription: Any area that receives less than 10 inches of precipitation per year. Rocky or sandy biome with little precipitation and plant life.

Locations: North Africa, S.W. Mexico, W. China, South America, Middle East, Australia, S.W. USA

Biotic Factors: Animals – burrowing rodents, jackrabbits, desert shrew, prairie dogs, coral snake, desert horned viper (snake), gila monster, iguana

Jackrabbit Desert shrew Prairie dog Desert horned viper snake

Plants – tumbleweed, prickly pear cacti, prickly poppies, blue-eyed grass, bitter root, golden desert snapdragon

Tumbleweed Prickly pear cactus Blue-eyed grass Golden desert snapdragon

Abiotic Factors:Climate – dry less than 10 inches of rainfall per yearAverage Temperature – 38oC (day) and -3.9 oC

Deserts cover about one fifth of the Earth's surface and occur where rainfall is less than 50 cm/year. Although most deserts, such as the Sahara of North Africa and the deserts of the southwestern U.S., Mexico, and Australia, occur at low latitudes, another kind of desert, cold deserts, occur in the basin and range area of Utah and Nevada and in parts of western Asia. Most deserts have a considerable amount of specialized vegetation, as well as specialized vertebrate and invertebrate animals. Soils often have abundant nutrients because they need only water to become very productive and have little or no organic matter. Disturbances are common in the form of occasional fires or cold weather, and sudden, infrequent, but intense rains that cause flooding.

There are relatively few large mammals in deserts because most are not capable of storing sufficient water and withstanding the heat. Deserts often provide little shelter from the sun for large animals. The dominant animals of warm deserts are non-mammalian vertebrates, such as reptiles. Mammals are usually small, like the kangaroo mice of North American deserts.

GrasslandsDescription: Grassland biomes are large, rolling terrains of grasses, flowers and herbs.

Locations: Veldts of Africa, pampas of South America, Steppes of Eurasia, and plains of North America

Biotic Factors:Animals: armadillo, pampas fox, elephants, zebras, wildebeest, rhinos, blesbok (like a deer type animal)

Zebra Pampas Fox Wildebeest

Plants: grasses, williows, cottonwoods, oaks (trees are sparse), buffalo grass, yellow indiangrass, switchgrass, blue grama

Buffalo grass Yellow Indiangrass Blue grama grass

Abiotic Factors: Climate - Climate is the most important factor in creating a savanna. Savannas are always found in warm or hot climates where the annual rainfall is from about 50.8 to 127 cm (20-50 inches) per year. It is crucial that the rainfall is concentrated in six or eight months of the year, followed by a long period of drought when fires can occur. If the rain

were well distributed throughout the year, many such areas would become tropical forest.

Average Temperature - -20 oC to 30 oC

Grasslands are characterized as lands dominated by grasses rather than large shrubs or trees. In the Miocene and Pliocene Epochs, which spanned a period of about 25 million years, mountains rose in western North America and created a continental climate favorable to grasslands. Ancient forests declined and grasslands became widespread. Following the Pleistocene Ice Ages, grasslands expanded in range as hotter and drier climates prevailed worldwide. There are two main divisions of grasslands:

Tropical grasslands or savannas Temperate grasslands

Tropical RainforestDescription: The tropical rain forest is a forest of tall trees in a region of year-round warmth.

Locations: Southeast Asia, South America, and Africa

Biotic Factors:Animals – Africa Forest elephant, dawn bat, Bengal tiger, proboscis monkey, Toco Toucan, Silvery Gibbon, King Cobra

African Forest Elephant Proboscis Monkey Silvery Gibbon Bengal Tiger

Plants – Bengal Bamboo, Curare, Kapok Tree, Mangrove Forests, Coconut Tree, Jambu, Strangler Figs

Bengal Bamboo Mangrove Forest Strangler Fig Kapok Tree

Abiotic Factors:Climate - In an average year in a tropical rain forest, the climate is very humid because of all the rainfall, which amounts to about 250 cm per year. The rain forest has lots of rain because it is very hot and wet. This climate is found near the equator. That means that there is more direct sunlight hitting the land and sea there than anywhere else. The sun warms the land and sea and the water evaporates into the air. The warm air can hold a lot of water vapor. As the air rises, it cools. That means it can hold less water vapor. Then as warm meets cold, condensation takes place and the vapor forms droplets, and clouds form. The clouds then produce rain. It rains more than ninety days a year and the strong sun usually shines between the storms.

Average Temperature – (high) 34 oC, and (low) 20 oC

Rainforests now cover less than 6% of Earth's land surface. Scientists estimate that more than half of all the world's plant and animal species live in tropical rain forests. Tropical rainforests produce 40% of Earth's oxygen.

A tropical rain forest has more kinds of trees than any other area in the world. Scientists have counted about 100 to 300 species in one 2 1/2-acre (1-hectare) area in South America. Seventy percent of the plants in the rainforest are trees.

About 1/4 of all the medicines we use come from rainforest plants. Curare comes from a tropical vine, and is used as an anesthetic and to relax muscles during surgery. Quinine, from the cinchona tree, is used to treat malaria. A person with lymphocytic leukemia has a 99% chance that the disease will go into remission because of the rosy periwinkle. More than 1,400 varieties of tropical plants are thought to be potential cures for cancer.

All tropical rain forests resemble one another in some ways. Many of the trees have straight trunks that don't branch out for 100 feet or more. There is no sense in growing branches below the canopy where there is little light. The majority of the trees have smooth, thin bark because there is no need to protect them from water loss and freezing temperatures. It also makes it difficult for epiphytes and plant parasites to get a hold on the trunks. The bark of different species is so similar that it is difficult to identify a tree by its bark. Many trees can only be identified by their flowers.

TaigaDescription: The taiga is the biome of the needleleaf forest. Living in the taiga is cold and lonely. Coldness and food shortages make things very difficult, mostly in the winter. Some of the animals in the taiga hibernate in the winter, some fly south if they can, while some just cooperate with the environment, which is very difficult.

Locations: Canada, Russia, Most of Alaska, and Siberia.

Biotic Factors: Animals – American Black bear, bobcat, Canadian lynx, grizzly bear, red fox, river otter, wolverine, snowshoe rabbit

American black bear Bobcat Wolverine Snowshoe rabbitPlants – balsam Fir, black spruce, jack Pine, Siberian Spruce, White Spruce, Paper Birch, White Poplar

Balsam Fir Siberian Spruce White Spruce Paper Birch

Abiotic Factors:

Climate - The Average Rainfall is 12-33 inches (30-84 cm) per year. The taiga climate is for the most part dominated by cold arctic air. Exceptionally cold winds bring bitterly cold air from the Arctic Circle: the temperatures fall even more on clear nights when there is no -cloud cover. Because of earth's tilt, the taiga is turned away from the sun in the winter. Less of the sun's radiation reaches the ground to warm it up. Winter, with it's freezing cold temperatures, lasts for six to seven months. Summer is a rainy, hot and short season in the taiga. Fall is the shortest season for taiga. Spring brings flowers, the frozen ponds melt, and the animals come out from hibernation.

Average Temperature - The temperature range, as you can see, is -65° F to 70°F (-54 to 21° C).

Taiga is the Russian word for forest and is the largest biome in the world. It stretches over Eurasia and North America. 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 is also known as the boreal forest. Did you know that Boreal was the Greek goddess of the North Wind?

The taiga doesn't have as many plant and animal species as the tropical or the deciduous forest biomes. It does have millions of insects in the summertime. Birds migrate there every year to nest and feed.

The main seasons in the taiga are winter and summer. The spring and autumn are so short, 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, hemlock and Douglas fir.

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.

Temperate Deciduous ForestDescription: Temperate deciduous forests or temperate broad-leaf forests are dominated by trees that lose their leaves each year. They are found in areas with warm, moist summers and mild winters.

Locations: Eastern North America, Middle of Europe, southwest Russia, Japan, and Eastern China

Biotic Factors:Animals – American Bald Eagle, American Black Bear, Coyote, Duckbill Platypus, Eastern Chipmunk, white-tailed deer, Least Weasel

American Bald Eagle Duckbill Platypus Eastern Chipmunk White Tailed Deer

Plants – American Beech, Carpet Moss, Common Lime, White Oak, White Birch, Lady Fern, Pecan, Shagbark Hickory

American Beech Carpet Moss White Oak Lady FernAbiotic Factors:Climate - One thing that is interesting about this biome and its climate is that it has four distinct seasons; spring, summer, autumn, and winter. Most deciduous forests have mild summers averaging about 70 °F. Summer months usually begin in early June and end in late August. Winter months don't begin until December. Winter temperatures are fairly cool with an average temperature of a little below freezing. Almost all of the world's deciduous forest is located by an ocean.

Climate is a mix of temperature and precipitation. Deciduous forests have almost 14 inches of rain in the winter months and more than 18 inches of rain in the summer.

Average Temperature – 500C

In deciduous forests there are five different zones. The first zone is the Tree Stratum zone. The Tree Stratum zone contains such trees as oak, beech, maple, chestnut hickory, elm, basswood, linden, walnut, and sweet gum trees. This zone has height ranges between 60 feet and 100 feet.

The small tree and sapling zone is the second zone. This zone has young, and short trees. The third zone is called the shrub zone. Some of the shrubs in this zone are rhododendrons, azaleas, mountain laurel, and huckleberries. The Herb zone is the fourth zone. It contains short plants such as herbal plants. The final zone is the Ground zone. It contains lichen, club mosses, and true mosses.

The deciduous forest has four distinct seasons, spring, summer, autumn, and winter. In the autumn the leaves change color. During the winter months the trees lose their leaves.

TundraDescription: Did you know that the Arctic Tundra is the world's youngest biome? It was formed 10,000 years ago. Located at latitudes 55° to 70° North, the tundra is a vast and treeless land which covers about 20% of the Earth's surface, circumnavigating the North pole. It is usually very cold, and the land is pretty stark. Almost all tundras are located in the Northern Hemisphere.

Locations: North Hemisphere,

Biotic Factors:Animals – arctic fox, caribou, ermine, grizzly bear, polar bear snowy owl

Arctic Fox Caribou Ermine Snowy owlPlants – arctic moss, arctic willow, bearberry, caribou moss, diamond-leaf willow, Labrador tea

Arctic moss Bearberry Diamond-leaf willow Labrador teaAbiotic Factors:Climate - 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.

Average Temperature – winter -200C to -300C, not higher than 200CTundra 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. This layer is called permafrost.

The bare and sometimes rocky ground can only support low growing plants like mosses, heaths, and lichen. In the winter it is cold and dark and in the summer, when the snow and the top layer of permafrost melt, it is very soggy and the tundra is covered with marshes, lakes, bogs and streams that breed thousands of insects and attract many migrating birds.

The main seasons are winter and summer. Spring and fall are only short periods between winter and summer. The tundra is the world's coldest and driest biomes. The average annual temperature is -18° F (-28° C). Nights can last for weeks when the sun barely rises during some months in the winter, and the temperature can drop to -94° F (-70° C). During the summer the sun shines almost 24 hours a day, which is why the Arctic is also called the Land of the Midnight Sun. Summer are usually warm. Temperatures can get up to 54° F (12° C), but it can get as cold as 37° F (3° C). Average summer temperatures range from 37° to 60°F (3° to 16°C).

The Arctic tundra is also a windy place and winds can blow between 30 to 60 miles (48 to 97 kilometers) per hour. Of the North American, Scandinavian and Russian tundra, the Scandinavian tundra is the warmest, with winter temperatures averaging 18°F (-8°C)

The tundra is basically like a desert when it comes to precipitation. Only about 6 - 10 inches of precipitation (mostly snow) 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 and marshes each summer.