comparison temperate and tropical temp rain 12

8/3/2019 Comparison Temperate and Tropical Temp Rain 12

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http://www.ucmp.berkeley.edu/exhibits/biomes/forests.php

Tropical forest

Tropical forests are characterized by the greatest diversity of species. They occur near the equator,within the area bounded by latitudes 23.5 degrees N and 23.5 degrees S. One of the majorcharacteristics of tropical forests is their distinct seasonality: winter is absent, and only two seasons

are present (rainy and dry). The length of daylight is 12 hours and varies little.

Temperature is on average 20-25° C and varies little throughout the year: the averagetemperatures of the three warmest and three coldest months do not differ by more than 5degrees.

Precipitation is evenly distributed throughout the year, with annual rainfall exceeding 2000

mm.

Soil is nutrient-poor and acidic. Decomposition is rapid and soils are subject to heavy leaching.

Canopy in tropical forests is multilayered and continuous, allowing little light penetration.

Flora is highly diverse: one square kilometer may contain as many as 100 different treespecies. Trees are 25-35 m tall, with buttressed trunks and shallow roots, mostly evergreen,with large dark green leaves. Plants such as orchids, bromeliads, vines (lianas), ferns, mosses,and palms are present in tropical forests.

Fauna include numerous birds, bats, small mammals, and insects.

Further subdivisions of this group are determined by seasonal distribution of rainfall:

evergreen rainforest : no dry season.

seasonal rainforest : short dry period in a very wet tropical region (the forest exhibits definiteseasonal changes as trees undergo developmental changes simultaneously, but the generalcharacter of vegetation remains the same as in evergreen rainforests).

semievergreen forest : longer dry season (the upper tree story consists of deciduous trees,while the lower story is still evergreen).

moist/dry deciduous forest (monsoon): the length of the dry season increases further asrainfall decreases (all trees are deciduous).

More than one half of tropical forests have already been destroyed.

Temperate forest

Temperate forests occur in eastern North America, northeastern Asia, and western and central Europe.Well-defined seasons with a distinct winter characterize this forest biome. Moderate climate and agrowing season of 140-200 days during 4-6 frost-free months distinguish temperate forests.

Temperature varies from -30° C to 30° C.

Precipitation (75-150 cm) is distributed evenly throughout the year.

Soil is fertile, enriched with decaying litter.

Canopy is moderately dense and allows light to penetrate, resulting in well-developed and

richly diversified understory vegetation and stratification of animals.

Flora is characterized by 3-4 tree species per square kilometer. Trees are distinguished bybroad leaves that are lost annually and include such species as oak, hickory, beech, hemlock,maple, basswood, cottonwood, elm, willow, and spring-flowering herbs.

Fauna is represented by squirrels, rabbits, skunks, birds, deer, mountain lion, bobcat, timberwolf, fox, and black bear.

Further subdivisions of this group are determined by seasonal distribution of rainfall:

moist conifer and evergreen broad-leaved forests: wet winters and dry summers (rainfall is

concentrated in the winter months and winters are relatively mild).






dry conifer forests: dominate higher elevation zones; low precipitation.

mediterranean forests: precipitation is concentrated in winter, less than 1000 mm per year.

temperate coniferous: mild winters, high annual precipitation (greater than 2000 mm).

temperate broad-leaved rainforests: mild, frost-free winters, high precipitation (more than1500 mm) evenly distributed throughout the year.

Only scattered remnants of original temperate forests remain.

http://rainforests.pwnet.org/4teachers/background.php

Comparison of Tropical & Temperate Rain Forests

Sometimes you hear the words "tropical" and "temperate" associated with rain forests. The difference is in thelocation. If the rain forest is close to the equator, it is considered tropical. If the rain forest is farther away from theequator (between the Arctic Circle and the Tropic of Cancer or the Antarctic Circle and the Tropic of Capricorn) thenthe forest is considered to temperate.

Since Alaska and the Pacific Northwest’s rain forests are found between the Arctic Circle and the Tropic of Cancer,these forests are temperate. All temperate rain forests share similar characteristics, but different plants and animals

populate each.

Tropical rain forests are located in the warm regions south of the Tropic of Cancer and north of the Tropic ofCapricorn. Tropical rain forests have the greatest biodiversity, but there are non-tropical or temperate rain forests aswell (such as those on the northwest coast of the USA). The only tropical rain forest in the United States is found onthe island of Puerto Rico.

Tropical rain forests are warm and moist; while temperate rain forests are cool.

Tropical Temperate

Temperatures warm cool

Number of tree species many (hundreds) few (10-20)

Types of leaves broadleaf needles

Age of trees 50-100 years 500-1000 years

Epiphytes lots of different kinds

including orchids andbromeliads

mostly mosses

and ferns

Decomposition rate rapid slow

Tropical Rain Forest Overview

The world's tropical forests, which circle the globe, are diverse. Ranging from thesteamy jungles of the rain forests to the dry forests and savannas, they provide habitatfor millions of species of plants and animals. Once covering some 15.3 billion acres






(6.2 billion ha), these tropical forests have been reduced through cutting and clearing by 210 million acres (85 millionha) between 1985 and 1990.

About half of all the world's forests are in the Tropics—the area between the Tropic of Cancer and the Tropic ofCapricorn. This region may be best known for its rain forests - lush, steamy jungles with towering trees, epiphytes,and dense under stories of smaller trees, shrubs, and vines.

Not all forests in the tropics are rain forests! Tropical forests are surprisingly diverse. In addition to rain forests, thereare mangroves, moist forests, dry forests, and savannas. Such classifications, however, give only a slight indicationof the diversity of tropical forests. One study by the Food and Agriculture Organization (FAO) of the United Nations,which considered 23 countries in tropical America, 37 in tropical Africa, and 16 in tropical Asia, identified dozens oftypes of tropical forests: open and closed canopy forests, broadleaved trees and conifer forests, closed forests andmixed forest grasslands, and forests where agriculture has made inroads.

The largest remaining areas of tropical rain forests are in Brazil, Congo, Indonesia, and Malaysia. Precipitationgenerally exceeds 60 inches (150 cm) per year and may be as high as 400 inches (1000 cm). Giant trees may tower200 feet (60 m) in height and support thousands of other species of plants and animals. Montane (mountain) rainforests grow at higher elevations where the climate is too windy and wet for optimum tree growth.

Mangrove forests grow in the swampy, intertidal margin between sea and shore and are often considered part of the

rain forest complex. The roots of mangrove trees help stabilize the shoreline and trap sediment and decayingvegetation that contribute to ecosystem productivity.

Dry Forests

Large areas of tropical dry forests are found in India, Australia, Central and South America, the Caribbean, Mexico,Africa, and Madagascar. Dry forests receive low rainfall amounts, as little as 20 inches (50 cm) per year, and arecharacterized by species well adapted to drought. Trees of dry tropical forests are usually smaller than those in rainforests, and many lose their leaves during the dry season. Although they are still amazingly diverse, dry forests oftenhave fewer species than rain forests.

Savanna is a transitional type between forest and grassland. Trees are often very scattered and tend to be welladapted to drought and tolerant of fire and grazing. If fire is excluded, trees eventually begin to grow and the savanna

is converted to dry forest. With too much fire or grazing, dry forest becomes savanna. This vegetation type has fewerspecies of trees and shrubs but more grasses and forbs than other forest types in the tropics.

All forests have both economic and ecological value, but tropical forests are especially important in global economy.These forests cover less than 6 percent of the Earth's land area, but they contain the vast majority of the world's plantand animal genetic resources. The diversity of life is astonishing. The original forests of Puerto Rico, for example,contain more than 500 species of trees in 70 botanical families. By comparison, temperate forests have relatively few.Such diversity is attributed to variations in elevation, climate, and soil, and to the lack of frost.

Wood and Other Products

Tropical forests provide many valuable products including rubber, fruits andnuts, meat, rattan, medicinal herbs, floral greenery, lumber, firewood, and

charcoal. Such forests are used by local people for subsistence hunting andfishing. They provide income and jobs for hundreds of millions of people insmall, medium, and large industries.

Tropical forests are noted for their beautiful woods. Four importantcommercial woods are mahogany, teak, melina, and okoume. Hondurasmahogany (Swietenia macrophylla), grows in the Americas from Mexico toBolivia. A strong wood of medium density, mahogany is easy to work, is longlasting, and has good color and grain. Teak is native to Southeast Asia and India. It is commonly used for furniture,molding, paneling and trim. Its wood has medium density, is strong, polishes well, and has a warm yellow-brown



color. Also prized for resistance to insects and rot, teak is commonly used in cabinets, trim, flooring, furniture, andboats. Melina (Gmelina arborea) grows naturally from India through Vietnam. Noted for fast growth, melina has lightcolored wood that is used mainly for pulp and particleboard, matches and carpentry. Okoume (Aucoumea klaineana)is native to Gabon an the Congo in west Africa. A large fast-growing tree, the wood has moderately low density, goodstrength-to density ratio, and low shrinkage during drying. It is commonly use (for plywood, paneling, interior furnitureparts, and light construction).

Other Economic Values

Tropical forests are home for tribal hunter-gatherers whose way of life has been relatively unchanged for centuries.These people depend on the forests for their livelihood. More than 2.5 million people also live in areas adjacent totropical forests. They rely on the forests for their water, fuelwood, and other resources and on its shrinking land basefor their shifting agriculture. For urban dwellers, tropical forests provide water for domestic use and hydroelectricpower. Their scenic beauty, educational value, and opportunities for outdoor recreation support tourist industries.

Many medicines and drugs come from plants found only in tropical rain forests. Some of the best known are quinine,an ancient drug used for malaria; curare, an anesthetic and muscle relaxant used in surgery; and rosy periwinkle, atreatment for Hodgkin's disease and leukemia. Research has identified other potential drugs that may have value ascontraceptives or in treating a multitude of maladies such as arthritis, hepatitis, insect bites, fever, coughs, and colds.Many more may be found. In all, only a few thousand species have been evaluated for their medicinal value.

Environmental Benefits

Tropical forests do more than respond to local climatic conditions; they actually influence the climate. Throughtranspiration, the enormous number of plants found in rain forests return huge amounts of water to the atmosphere,increasing humidity and rainfall, and cooling the air for miles around. In addition, tropical forests replenish the air byutilizing carbon dioxide and giving off oxygen. By fixing carbon they help maintain the atmospheric carbon dioxidelevels low and counteract the global "greenhouse" effect.

Forests also moderate stream flow. Trees slow the onslaught of tropical downpours, use and store vast quantities ofwater, and help hold the soil in place. When trees are cleared, rainfall runs off more quickly, contributing to floods anderosion.

Status of Tropical Rain Forests

Before the dawn of agriculture approximately 10,000 years ago, forests and open woodland covered about 15.3billion acres (6.2 billion ha) of the globe. Over the centuries, however, about one-third of these natural forests hasbeen destroyed. According to a 1982 study by FAO, about 27.9 million acres (11.3 million ha) of tropical forests arecut each year-an area about the size of the states of Ohio or Virginia. Between 1985 and 1990, an estimated 210million acres (85 million ha) of tropical forests were cut or cleared. In India, Malaysia, and the Philippines, the bestcommercial forests are gone, and cutting is increasing in South America. If deforestation is not stopped soon, theworld will lose most of its tropical forests in the next several decades.

Reasons for Deforestation

Several factors are responsible for deforestation in the Tropics: clearing for agriculture, fuelwood cutting, and

harvesting of wood products. By far the most important of these is clearing for agriculture. In the Tropics, the age-oldpractice of shifting, sometimes called "slash-and-burn," agriculture has been used for centuries. In this primitivesystem, local people cut a small patch of forest to make way for subsistence farming. After a few years, soil fertilitydeclines and people move on, usually to cut another patch of trees and begin another garden.

In the abandoned garden plot, the degraded soil at first supports only weeds and shrubby trees. Later, soil fertility andtrees return, but that may take decades. As population pressure increases, the fallow (rest) period between cycles ofgardening is shortened, agricultural yields decrease, and the forest region is further degraded to small trees, brush, oreroded savanna. Conversion to sedentary agriculture is an even greater threat to tropical forests. Vast areas that



once supported tropical forests are now permanently occupied by subsistence farmers and ranchers and bycommercial farmers who produce sugar, cocoa, palm oil, and other products.

In many tropical countries there is a critical shortage of firewood. For millions of rural poor, survival depends onfinding enough wood to cook the evening meal. Every year more of the forest is destroyed, and the distance fromhome to the forest increases. Not only do people suffer by having to spend much of their time in the search for wood,but so does the land. Damage is greatest in dry tropical forests where firewood cutting converts forests to savannasand grasslands.

The global demand for tropical hardwoods, an $8-billion-a-year industry, also contributes to forest loss. Tropicalforests are usually selectively logged rather than clear-cut. Selective logging leaves the forest cover intact but usuallyreduces its commercial value because the biggest and best trees are removed. Selective logging also damagesremaining trees and soil, increases the likelihood of fire, and degrades the habitat for wildlife species that requirelarge, old trees-the ones usually cut. In addition, logging roads open up the forests to shifting cultivation andpermanent settlement.

In the past, logging was done primarily by primitive means-trees were cut with axes and logs were moved withanimals such as oxen. Today the use of modern machinery--chain saws, tractors, and trucks -makes logging easier,faster, and potentially more destructive.

Endangered Wildlife

Forests are biological communities-complex associations of trees with other plants and animals that have evolvedtogether over millions of years. Because of the worldwide loss of tropical forests, thousands of species of birds andanimals are threatened with extinction. The list includes many unique and fascinating animals, among them theorangutan, mountain gorilla, manatee, jaguar, and Puerto Rican parrot. Although diverse and widely separatedaround the globe, these species have one important thing in common. They, along with many other endangeredspecies, rely on tropical forests for all or part of their habitat.

Orangutans (Pongo pygmaeus) are totally dependent on small and isolated patches of tropical forests remaining inBorneo and Sumatra, Indonesia. Orangutans spend most of their time in the forest canopy where they feed onleaves, figs and other fruit, bark, nuts, and insects. Large trees of the old-growth forests support woody vines thatserve as aerial ladders, enabling the animals to move about, build their nests, and forage for food. When the old

forests are cut, orangutans disappear.

The largest of all primates, the gorilla, is one of man's closest relatives in the animal kingdom. Too large and clumsyto move about in the forest canopy, the gorilla lives on the forest floor where it forages for a variety of plant materials.Loss of tropical forests in central and west Africa is a major reason for the decreasing numbers of mountain gorillas(Gorilla gorilla). Some habitat has been secured, but the future of this gentle giant is in grave danger as a result ofhabitat loss and poaching.

The jaguar (Leo onca), a resident of the Southwestern United States and Central and South America, is closelyassociated with forests. Its endangered status is the result of hunting and habitat loss.

The Puerto Rican parrot (Amazona vittata), a medium-sized, green bird with blue wingfeathers, once inhabited the entire island of Puerto Rico and the neighboring islands ofMona and Culebra. Forest destruction is the principal reason for the decline of thisspecies. Hunting also contributed. Today, only a few Puerto Rican parrots remain inthe wild and their survival may depend on the success of a captive breeding program.

In addition to species that reside in tropical forests year round, others depend on suchforests for part of the year. Many species of migrant birds journey 1,000 miles or morebetween their summer breeding grounds in the north and their tropical winteringgrounds. These birds are also threatened by tropical forest destruction.



New Directions in Tropical Forestry

The conservation issues of the past seem simple compared with those of today. As we move toward the 21st century,human societies are concerned with global warming, deforestation, species extinction, and rising expectations.Growing populations must be fed, clothed, and sheltered, and people everywhere want higher standards of living.

Global Warming

Warming of the earth's atmosphere is a major environmental issue. Airpollution, deforestation, and widespread burning of coal, oil, and natural gashave increased atmospheric concentrations of carbon dioxide, methane,nitrous oxide, and chlorofluorocarbons. These gases trap heat from the sunand prevent it from radiating harmlessly back into space. Thus, the 64greenhouse" or warming effect is created.

Because of natural variations in climate, it is difficult to measure warmingover large areas. Scientists agree, however, that increases in atmosphericconcentrations of greenhouse gases will cause higher temperaturesworldwide. Even an increase of a few degrees might cause serious melting of the polar icecaps, a gradual rise in sealevel, a disruption in normal weather patterns, a possible increase in forest fires, and the extinction of species.

Role of Forests

Trees, the largest of all land plants, act as a kind of environmental "buffer" for the ecosystem they dominate. Theyhelp ameliorate the extremes of climate (heat, cold, and wind) and create an environment where large landmammals, including people, can live comfortably. Trees complement animals in the global environment. Mammalstake in oxygen from the air and exhale carbon dioxide. Plants use the carbon dioxide in their growth processes, storethe carbon in woody tissues, and return oxygen to the atmosphere as a waste product. This process, known asphotosynthesis, is essential to life. Carbon captured from the atmosphere by photosynthesis is eventually recycledthrough the environment in a process known as the carbon cycle. Trees have an especially important role in thecarbon cycle. Tree leaves also act as filters to remove atmospheric pollutants from the air. This effect is particularlybeneficial in urban areas.

Forestry Issues

Two key issues will dominate forestry in the years ahead: (1) maintaining long-termproductivity of managed forests, and (2) preventing further loss of tropical forests. Bothproblems will require new approaches to forest management. Traditionally, forestryhas focused on growing crops of wood in plantations or in managed natural stands. Inthis "agricultural mode," other benefits of forest such as watershed protection, wildlifehabitat, climate moderation, and outdoor recreation, have received less attention thanwood production.

Perhaps more importantly, the sustainability of the full range of forest benefits has notbeen measured. There is no question that trees can be grown for crops of wood inmanaged stands. With intensive management-short rotations, species selection,

genetic improvement, fertilization, thinning, and other cultural treatments-more woodcan be produced in less time than in natural forests. But for how long? And at whatcost in other benefits?

As more and more of the world's original forests have been cut, the ecological value offorests has come to be more appreciated. In recent years, increased emphasis has been put on what some arecalling "ecosystem management." In this model, the health and long-term stability of the forest are paramount, andtimber production is considered a byproduct of good forest management rather than the principal product. In PuertoRico, for example, wood production is a relatively minor aspect of forestry.



Since the 1930's when timber harvests were curtailed, the forests have been managed primarily for watershedprotection, wildlife habitat, and outdoor recreation.

There are no easy solutions to the problem of tropical forest destruction, but most experts agree that the problemscannot be solved simply by locking up the forests in reserves. The forests are too important to local people for that tobe a workable solution. There is no doubt that tropical forests will be cut. It is better for them to be cut in anecologically sound manner than to be cleared for poor-quality farmland or wasted by poor harvest practices.

The only real long-term solutions are: (1) more efficient agriculture on suitable farmland, (2) efficient forestry practiceincluding plantations, and (3) reserves to protect species and ecosystems. Many forestry experts believe that wehave only begun to tap the potential for wise use of tropical forests. Many uses have yet to be fully explored. We areonly starting to learn the value of tropical forests for medicines, house and garden plants, food and fiber, tourism, andnatural resource education.

http://mbgnet.net/sets/rforest/explore/layers.htm

Tropical rainforests have four layers:

Emergent Layer These giant trees thrust above the dense canopy layer and havehuge mushroom-shaped crowns. These trees enjoy the greatestamount of sunlight but also must endure high temperatures, lowhumidity, and strong winds.

Canopy Layer The broad, irregular crowns of these trees form a tight, continuous

canopy 60 to 90 feet above the ground. The branches are oftendensely covered with other plants (epiphytes) and tied togetherwith vines (lianas). The canopy is home to 90% of the organismsfound in the rain forest; many seeking the brighter light in thetreetops.

Understory Receiving only 2-15% of the sunlight that falls on the canopy, theunderstory is a dark place. It is relatively open and contains youngtrees and leafy herbaceous plants that tolerate low light. Manypopular house plants come from this layer. Only along rivers androadways and in treefall and cut areas is sunlight sufficient to allowgrowth to become thick and impenetrable

Forest Floor The forest floor receives less than 2% of the sunlight and






consequently, little grows here except plants adapted to very lowlight. On the floor is a thin layer of fallen leaves, seeds, fruits, andbranches that very quickly decomposes. Only a thin layer of decaying organic matter is found, unlike in temperate deciduous

forests.

Soil and Nutrient Recycling Most tropical rainforest soils relatively poor in nutrients. Millions of years of weathering and torrential rains have washed most of thenutrients out of the soil. More recent volcanic soils, however, can bevery fertile. Tropical rain forest soils contain less organic matterthan temperate forests and most of the available nutrients arefound in the living plant and animal material. Nutrients in the soilare often in forms that are not accessible by plants.

Constant warmth and moisture promote rapid decay of organicmatter. When a tree dies in the rainforest, living organisms quicklyabsorb the nutrients before they have a chance to be washed away.

When tropical forests are cut and burned, heavy rains can quicklywash the released nutrients away, leaving the soil even moreimpoverished.



Comparison of Where Nutrients Are Found in an EcosystemBased on the Averaging of Major Nutrients.

Tropical Rainforest Temperate Deciduous Forest

52% in Vegetation 31% in Vegetation

48% in Soil

69% in Soil

http://www.defenders.org/wildlife_and_habitat/habitat/forest.php

Tropical RainforestLocation: The tropical rainforests contain the greatest diversity of species of all biomes on earth. They are foundaround the equator, between 23.5 degrees N latitude and 23.5 degrees S latitude.

Climate: Temperatures in tropical rainforests remain between 68 and 77 degrees Fahrenheit all year long. Winter isabsent in these forests. Most tropical rainforests receive 100 inches of rain per year.

Soil: Because the temperature is warm and the air moist, decomposition happens at a very fast rate in tropicalrainforests. High levels of rainfall often lead to leaching of nutrients from the soil, creating soils that are nutrient poor.

Plants: Trees in the tropical rainforests grow between 82 and 115 feet tall and are typically broad-leafed trees. Otherplants include ferns, vines, mosses, palms and orchids.

Animals: Dense growing trees create a thick canopy layer in tropical rainforests that keep the sun from penetrating tothe lower layers of the forest. This means that most animals that live here must be adapted to living in the trees. Avariety of birds, bats, monkeys, snakes and other animals can be found in tropical rainforests.

Threats: The biggest threat to tropical rainforests is unsustainable forestry practices. Other threats include roadconstruction, clearing land for agriculture and other development activities and climate change.

Temperate Deciduous ForestLocation: Eastern United States and Canada, Western Europe and parts of Russia, China and Japan.

Climate: There are four distinct seasons in temperate deciduous forests and precipitation falls throughout the year,as rain in the spring, summer and fall and snow in the winter. Temperate deciduous forests receive 30-60 inches ofrain per year.

Soil: The soil in these forests is very fertile.

Plants: The forest floor in temperate deciduous forests supports mosses, ferns and wildflowers and the understorysupports a variety of shrubs and ferns. Maple, oak and birch trees are some examples of the deciduous trees thatdominate these forests. There are also small numbers of evergreen trees such as pines and fir.

Animals: Animals living in temperate deciduous forests must be adapted to cold winters. Common species found intemperate deciduous forests include, red fox, hawks, woodpecker and cardinals.

Threats: Acid rain caused by industrial and vehicular emissions poses the biggest threat to temperate deciduous

forests. Over time, acid rain damages tree leaves, causes trees to produce fewer and smaller seeds and reducesresistance to disease. Other threats include unsustainable forestry, strip mining and the spread of invasive, non-native species that compete for space and food. Climate change is also a threat.

Temperate Coniferous ForestLocation: Temperate coniferous forests are typically found in coastal areas with mild winters and heavy rainfall or inin-land mountainous areas with mild climates. Examples of where these forests are found are Pacific NorthwesternUnited States and Canada, southwestern South America, Southern Japan, New Zealand and small parts ofnorthwestern Europe (Ireland, Scotland, Iceland and Norway).






Climate: Temperate climate with temperature that fluctuates little throughout the year. High levels of precipitation(50-200 inches per year) cause a moist climate and a long growing season.

Soil: Soils are generally rich with a thick layer of decaying material.

Plants: Evergreen conifers dominate these forests. Due to the high levels of precipitation and moderatetemperatures, there is a long growing season, resulting in trees that grow very tall. Dominant tree species found in

temperate coniferous forests include cedar, cypress, Douglas fir, pine, spruce and redwood. There are somedeciduous trees such as maple, and mosses and ferns are common.

Animals: Examples of animals that live in temperate coniferous forests are, deer, marmot, elk, black bear, salmon,spotted owl, marbled murrelet

Threats: Unsustainable forestry, road construction and other development related activities are the biggest threat totemperate deciduous forests.

Boreal (taiga) forestLocation: This is the northern most forest type and is found between 50 and 60 degrees N latitude. Boreal forestsare found in Canada, northern Asia, Siberia and Scandinavia (Denmark, Norway, Sweden, Finland). About two-thirdsof the world's boreal forests are found in Scandinavia.

Climate: Boreal forests are characterized by long winters and short summers. Most precipitation is in the form ofsnow and these forests receive between 15 and 40 inches of precipitation per year.

Soil: Because of cold temperatures, decomposition takes a long time, resulting in thin soil.

Plants: Trees are mostly evergreen and include species such as spruce, fir and pine. The understory is limitedbecause the canopy is so dense.

Animals: Animals found here must be adapted to long, cold winters and usually have thick fur. Deer, moose, elk,caribou, snowshoe hare, wolves, grizzly bears, lynxes and wolverines are some examples.

Threats: Unsustainable forestry, climate change, oil and gas drilling

http://answers.yahoo.com/question/index?qid=20080714014015AA7sPm0

Tropical: A tropical rainforest is located near the equator and is warm and moist.Temperate: A temperate rainforest is generally located around coastal areas and is cooler than a tropical rainforest.

The two types of rainforest are similar in a number of ways.

They both have dense vegetation. This means that the plants that grow in the rainforest are numerous and cover a lotof space.The diversity of the animal and plant species in the rainforests is greater than in any other ecosystem in the world.Both types of rainforest are lush and wet. This means that there is a lot of moisture from the rivers and streams in theforests as well as from the air, which is humid. This also means that the things that grow in the rainforests grow verywell.The two types of rainforest differ in several distinct ways.

Tropical rainforests have a greater diversity of species and more lush growth.A temperate rainforest has a seasonal climate, and as a result there is less diversity of animal and plant species. Theseasonal climate means that there are periods in the year where growth is not at its best. When certain species in thisdelicate environment are affected, then the majority of the species will feel an impact.Tropical rainforests have trees with broad leaves, whereas the leaves of trees in a temperate rainforest are generallyneedle-like.Decomposition occurs at a very rapid rate in a tropical rainforest, but in a temperate rainforest it occurs at a muchslower pace.




comparison temperate and tropical temp rain 12

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