Tropical Rainforest
1.Description
” Tropical Rainforest, also spelled tropical rain forest, luxuriant forest, generally composed of broad-leaved trees and found in wet tropical uplands and lowlands around the Equator.
2.Abiotic Factors
” Rain forests belong to the tropical wet climate group. The temperature in a rain forest rarely gets higher than 93 °F or drops below 68 °F average humidity is between 77% and 88%; rainfall is often more than 100 inches a year. There is usually a short season of less rain.
3.Biotic Factors
” Rainforests vegetation types are dominated by broad-leaved trees that form a dense upper canopy (layer of foliage) and contain a diverse array of vegetation. Rainforests are home to an incredibly diverse range of animals and plants such as anteaters, toucans, spider monkeys, tigers, sloths, frogs, orangutans, and many more.
4.Geographic Distribution
” Tropical rainforests grow mainly in three regions: the Malesian botanical subkingdom, tropical Southand Central America, and West and Central Africa. Smaller areas of tropical rainforest occur in the tropics wherever climate is suitable. The main areas of tropical rainforest are in India, the Myanmar-Vietnam-southern coastal China region, and eastern Brazil, with smaller areas in South and Central America north of the Equator, the West Indies, southeastern Africa, and northern Australia.
5.Special Characteristics
” There are four layers of rainforest: emergent, upper canopy, lower canopy, and forest floor.
Tropical Dry Forest
1.Description
” Tropical Dry Forests are a unique containing many species unique to the ecosystem. These forests are characterized by a pronounced dry season during part of the year
2.Abiotic Factors
” Though these forests occur in climates that are warm year-round, and may receive several hundred centimeters of rain per year, they have long dry seasons which last several months and vary with geographic location.
3.Biotic Factors
” Although they are less diverse than rainforests, tropical dry forests are home to a wide variety of wildlife including monkeys, deer, large cats, parrots, various rodents, and ground dwelling birds. Many of these species display extraordinary adaptations to the difficult climate.
4.Geographic Distribution
” Dry forests tend to exist in the drier areas north and south of the tropical rainforest belt, south or north of the subtropical deserts, such as South America, South Africa, the Pacific Coast, and India. Deciduous trees predominate in most of these forests,
5.Special Characteristics
” Dry forests are highly sensitive to excessive burning and deforestation; overgrazing and exotic species can also quickly alter natural communities.
Tropical Savanna
1.Description
” A savanna is a rolling grassland scattered with shrubs and isolated trees, which can be found between a tropical rainforest and desert biome. Not enough rain falls on a savanna to support forests. Savannas are also known as tropical grasslands. They are found in a wide band on either side of the equator on the edges of tropical rainforests.
2.Abiotic Factors
” Savannas have warm temperature year-round. There are actually two very different seasons in a savanna; a very long dry season and a very wet season. In the dry season only, an average of about 4 inches of rain falls. Between December and February no rain will fall at all. Oddly enough, it is actually a little cooler during this dry season, but it is still around 70° F.
3.Biotic Factors
” Most of the animals on the savanna have long legs or wings to be able to go on long migrations. Many burrow undergrounds to avoid the heat or raise their young. The savanna is a perfect place for birds of prey like hawks and buzzards. The wide, open plain provides them with a clear view of their prey, hot air updrafts keep them soaring, and there is the occasional tree to rest on or nest in. Animals don’t sweat to lose body heat, so they lose it through panting or through large areas of exposed skin, or ears, like those of the elephant. The savanna has a large range of highly specialized plants and animals. They all depend on the each other to keep the environment in balance.
4.Geographic Distribution
” The largest areas of savanna are found in Africa, South America, Australia, India, the Myanmar Burma Thailand region in Asia, and Madagascar.
5.Special Characteristics
” Savannas are found in a wide band on either side of the equator on the edges of tropical rainforests.
Desert
1.Description
” A desert is a barren area of landscape where little precipitation occurs and consequently living conditions are hostile for plant and animal life. A desert is a region of land that is very dry because it receives low amounts of precipitation
2.Abiotic Factors
” There are usually two or three variations of a desert climate: a hot desert climate, a cold desert climate and, sometimes, a mild desert climate. An area that features this climate usually experiences from 25 to 200 mm (7.87 inches) per year of precipitation and in some years may experience no precipitation at all.
3.Biotic Factors
” Plants and animals living in the desert need special adaptations to survive in the harsh environment. Plants tend to be tough and wiry with small or no leaves, water-resistant cuticles and often spines to deter herbivory. Many are nocturnal and stay in the shade or underground during the heat of the day. They tend to be efficient at conserving water, extracting most of their needs from their food and concentrating their urine. Some animals remain in a state of dormancy for long periods, ready to become active again when the rare rains fall.
4.Geographic Distribution
” Deserts cover about one fifth of the Earth’s surface including the Sahara of North Africa and the deserts of the southwestern U.S., Mexico, Australia, and Atacama of Chile.
5.Special Characteristics
” Deserts are formed by weathering processes as large variations in temperature between day and night put strains on rocks, causing them to break into pieces.
Temperate Grassland
1.Description
” Grasslands are characterized as lands dominated by grasses rather than large shrubs or trees.
2.Abiotic Factors
” Summer temperatures can be well over 100 degrees Fahrenheit, while winter temperatures can be as low as -40 degrees Fahrenheit. They typically have between 10 and 35 inches of precipitation a year, much of it occurring in the late spring and early summer.
3.Biotic Factor
” Temperate grasslands have a low diversity of wildlife, but a high abundance of wildlife. In North America the dominant grazing animals are bison and pronghorn. Grasses are the dominant vegetation. Trees and large shrubs are largely absent. Seasonal drought, occasional fires and grazing by large mammals all prevent woody shrubs and trees from becoming established.
4.Geographic Distribution
” The major temperate grasslands include the veldts of Africa, the pampas of South America, the steppes of Eurasia, and the plains of North America.
5.Special Characteristics
” Temperate grasslands have some of the darkest, richest soils in the world. People who live in grassland regions often use these soils for farming.
Temperate Woodland and Shrubland
1.Description
” Temperate woodlands and shrub lands are characterized by semiarid climate and a mix of shrub communities and open woodlands.
2.Abiotic Factors
” The temperature differs by seasons. It is hot and dry in the summer and cool and moist in the winter. Shrub lands receive less rain than forested areas, but more rain than deserts and grasslands. There is an average rainfall between 200-1000 mm per year.
3.Biotic Factors
” The most dominate plant life includes Aromatic herbs such as sage, rosemary, woody evergreen shrubs, fragrant oily herbs, thyme, shrubs, and other grasses. The most dominate wildlife are coyotes, foxes, bobcats, mountain lions, black tailed deer, wild goats, rabbits, squirrels, quails, warblers, songbirds, lizards, snakes, mule deer, and gecko.
4.Geographic Distribution
” Temperate woodlands and shrub lands cover the western coasts of North and South America, Australia, South Africa, and areas surrounding the Mediterranean Sea.
5.Special Characteristics
” The growth of dense, low plants that contain flammable oils make fires a constant threat.
Temperate Forest
1.Description
” Temperate forests, also know as temperate rain forest, contain a mixture of deciduous and coniferous trees. Mild, moist air from the Pacific Ocean provides abundant rainfall to this biome that is made up from a variety of conifers and animals.
2.Abiotic Factors
” Compared to the arctic tundra, the climate of the boreal forest is characterized by a longer and warmer growing season. Precipitation averages 20 inches per year but ranges from 40 inches in the eastern regions to 10 inches in interior Alaska. Available soil moisture is high as a result of cool temperature and low evapotranspiration rates. Mineral soils are generally thin and poorly drained.
3.Biotic Factors
” Dominant temperate forest wildlife includes deer; black bears; bobcats; nut and acorn feeders such as squirrels; omnivores such as raccoons and skunks; songbirds; and turkeys.
4.Geographic Distribution
” Temperate forests are spread across certain parts of eastern United States; southeastern Canada; most of Europe; and parts of Japan, China and Australia.
5.Special Characteristics
” Soils of temperate forest are humus rich. Humus is a material formed from decaying leaves and other organic matter that causes the soul to be fertile.
Northwestern Coniferous Forest
1.Description
” Coniferous forests grow in a wide range of climates, from the coldest polar regions to the warmest tropical regions and everything in between. The reason they’re so prevalent worldwide is because they take advantage of certain environmental conditions that other trees aren’t able to live in as well.
2.Abiotic Factors
” The abiotic factors of these forest include mild temperatures; abundant precipitation during fall, winter and spring; relatively cool, dry summers; and rocky, acidic soils.
3.Biotic Factors
” Northwestern coniferous forest consists mostly of conifers, trees that grow needles instead of leaves, and cones instead of flowers. Conifers tend to be evergreen, that is, they bear needles all year long. These adaptations help conifers survive in areas that are very cold or dry. Some of the more common conifers are spruces, pines, and firs. The more dominant animals include bears, elk, deer, beavers, owls, bobcats, and members of the weasel family.
4.Geographic Distribution
” Northwestern coniferous forest cover parts of the Pacific coast of northwestern United States and Canada, from northern California all the way to Alaska
5.Special Characteristics
” Temperate forest regions have cold, long snowy winters, and warm humid summer; well defined season, at least four to six frost-free months. Mild, moist air from the Pacific Ocean provides abundant rainfall to this biome.
Boreal Forest
1.Description
” Boreal forests, also known as taigas, are cold, dense evergreen forest of coniferous trees along the northern edge of the temperate zone with a swampy nature. They are the world’s largest biome apart from oceans. A third of all Boreal forests are found in Canada.
2.Abiotic Factors
” Boreal forests have long, cold winters; short, mild summers; moderate precipitation; high humidity; and acidic nutrient-poor soils.
3.Biotic Factors
” Dominant plants in taigas are needle leaf coniferous trees such as spruce and fir; some broadleaf deciduous trees; and small, berry-bearing shrubs. The prominent animals are lynxes, timber wolves, moose, beavers, songbirds, migratory birds, members of the weasel family.
4.Geographic Distribution
” Taigas can be found in broad bands throughout North America, Asia, and northern Europe.
5.Special Characteristics
” Boreal forests high level of intactness has made the forest a particular focus of environmentalists and conservation scientists who view the untouched regions of the forest as the perfect opportunity for large-scale conservation that would otherwise be impractical in other biomes.
Tundra
1.Description
” Tundra is the coldest of all land biomes. The tundra is characterized by its layer of permanently frozen subsoil, also known as permafrost.
2.Abiotic Factors
” Tundra faces strong winds; low precipitation; short and soggy summers; long, cold, and dark winter; poorly developed soil; and subsoil that is permanently frozen.
3.Biotic Factors
” The cycle of thawing and freezing that soil goes through rips and crushes plant roots causing small and stunted plants. The vegetation is composed of dwarf shrubs, sedges and grasses, mosses, and lichens. Scattered trees grow in some tundra regions.
4.Geographic Distribution
” Tundra covers parts of northern North America, Asia, Europe, and Antarctica and several Antarctic and sub-antarctic islands, including South Georgia and the South Sandwich Islands and the Kerguelen Islands
5.Special Characteristics
” The tundra is a type of biome where the tree growth is hindered by low temperatures and short growing seasons. During the short, cool summer, the ground thaws to a depth of a few cm and becomes soggy and wet, but it freezes again in the winter.