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A fundamental classification of biomes is into: Terrestrial (land) biomes Freshwater biomes Marine biomes

Biomes are climatically and geographically defined areas of ecologically similar climatic conditions such as communities of plants, animals, and soil organisms,[1] and are often referred to as ecosystems. Biomes are defined by factors such as plant structures (such as trees, shrubs, and grasses), leaf types (such as broadleaf and needleleaf), plant spacing (forest, woodland, savanna), and climate. Unlike ecozones, biomes are not defined by genetic, taxonomic, or historical similarities. Biomes are often identified with particular patterns of ecological succession and climax vegetation (quasi-equilibrium state of the local ecosystem). An ecosystem has many biotopes and a biome is a major habitat type. A major habitat type, however, is a compromise, as it has an intrinsic inhomogeneity. The biodiversity characteristic of each biome, especially the diversity of fauna and subdominant plant forms, is a function of abiotic factors and the biomass productivity of the dominant vegetation. In terrestrial biomes, species diversity tends to correlate positively with net primary productivity, moisture availability, and temperature.[2]

What is Deforestation Deforestation is defined as the destruction of forested land. It has proved to be a major problem all over world. However, the rates of destruction of forests are particularly high in the tropics. Causes of Deforestation The causes of deforestation vary form place to place. The most common causes, however, are logging, agricultural expansion, wars, and mining, Effects of Deforestation Deforestation has been the cause of many problems facing the world today such as erosions, loss of biodiversity through extinction of plant and animal species, and increased atmospheric carbon dioxide. Importnace of Vegetation Deforestation consequently decrease the supply of oxygen found on earth. Oxygen is essential to the existence of all living things and without it every living creature (including humans) will not be able to sustain life. In addition, forests provide homes for many important species such as the Northern Spotted Owl which can only survive in the northwestern United States . Furthermore, forests prevent desertification by replenishing nutrients in the land. These are just a few reasons why forests are soon important.  

What is Deforestation Deforestation is defined as the destruction of forested land. It has proved to be a major problem all over world. However, the rates of destruction of forests are particularly high in the tropics. Causes of Deforestation The causes of deforestation vary form place to place. The most common causes, however, are logging, agricultural expansion, wars, and mining, Effects of Deforestation Deforestation has been the cause of many problems facing the world today such as erosions, loss of biodiversity through extinction of plant and animal species, and increased atmospheric carbon dioxide. Importnace of Vegetation Deforestation consequently decrease the supply of oxygen found on earth. Oxygen is essential to the existence of all living things and without it every living creature (including humans) will not be able to sustain life. In addition, forests provide homes for many important species such as the Northern Spotted Owl which can only survive in the northwestern United States . Furthermore, forests prevent desertification by replenishing nutrients in the land. These are just a few reasons why forests are soon important.   CLICK ON A REGION BELOW Africa South America North and Central America Europe Asia Oceania     Back to top | Home | Deforestation | Prevent | Interact | Bibliography | Contact ©2005 Copyright© Think Quest Team All Rights Reserved  

    Deforestation What is Deforestation Deforestation is defined as the destruction of forested land. It has proved to be a major problem all over world. However, the rates of destruction of forests are particularly high in the tropics. Causes of Deforestation The causes of deforestation vary form place to place. The most common causes, however, are logging, agricultural expansion, wars, and mining, Effects of Deforestation Deforestation has been the cause of many problems facing the world today such as erosions, loss of biodiversity through extinction of plant and animal species, and increased atmospheric carbon dioxide. Importnace of Vegetation Deforestation consequently decrease the supply of oxygen found on earth. Oxygen is essential to the existence of all living things and without it every living creature (including humans) will not be able to sustain life. In addition, forests provide homes for many important species such as the Northern Spotted Owl which can only survive in the northwestern United States . Furthermore, forests prevent desertification by replenishing nutrients in the land. These are just a few reasons why forests are soon important.

Deforestation is the clearance of naturally occurring forests by the processes of logging and/or burning of trees in a forested area. There are several reasons deforestation occurs: trees or derived charcoal can be sold as a commodity and used by humans, while cleared land is used as pasture, plantations of commodities and human settlement. The removal of trees without sufficient reforestation has resulted in damage to habitat, biodiversity loss and aridity. Deforested regions typically incur signicifant adverse soil erosion and frequently degrade into wasteland. Disregard or ignorance of intrinsic value, lack of ascribed value, lax forest management and deficient environmental law are some of the factors that allow deforestation to occur on a large scale. In many countries, deforestation is an ongoing issue that is causing extinction, changes to climatic conditions, desertification, and displacement of indigenous people. However, among countries with a per capita GDP of at least $4,600, net deforestation rates have ceased to increase

It is estimated that nearly half of the world's estimated 10 million species of plants, animals, and microorganisms will be destroyed or severely threatened over the next quarter-century due to rainforest deforestation.

Commercial logging is the single largest cause of rainforest destruction, both directly and indirectly. Other activities destroying the rainforest, including clearing land for grazing animals and subsistence farming. The simple fact is that people are destroying the Amazon rainforest and the rest of the rainforests of the world because "they can't see the forest for the trees."

When a medicine man dies without passing his arts on to the next generation, the tribe and the world loses thousands of years of irreplaceable knowledge about medicinal plants.

Central America offers great biodiversity, but development, tree cutting, farming, and pollution threaten the region’s natural places.

Europe has 321 butterfly species, while a park in the rainforest of Peru (Manu National Park) has 1300 species.

the United States has 81 species of frogs, while Madagascar which is smaller than Texas, may have 300 species.

Europe has 321 butterfly species, while a park in the rainforest of Peru (Manu National Park) has 1300 species.

Many species of animal life can be found in the rain forest. Common characteristics found among mammals and birds (and reptiles and amphibians, too) include adaptations to a life in the trees, such as the prehensile tails of New World monkeys. Other characteristics are bright colors and sharp patterns, loud vocalizations, and diets heavy on fruits. Insects make up the largest single group of animals that live in tropical forests. They include brightly colored butterflies, mosquitoes, camouflaged stick insects, and huge colonies of ants. The Amazon river basin rainforest contains a wider variety of plant and animal life than any other biome in the world. The second largest population of plant and animal life can be found in scattered locations and islands of Southeast Asia. The lowest variety can be found in Africa. There may be 40 to 100 different species in 2.5 acres ( 1 hectare) of a tropical rain forest.   When early explorers first discovered the rainforests of Africa, Southeast Asia and South America, they They were amazed by the dense growth, trees with giant buttresses, vines and epiphytes . The tropical vegetation grew so dense that it was difficult to cut one's way through it. It was thought at the time that the soil of a rainforest must be very fertile, filled with nutrients, enabling it to support the immense trees and other vegetation they found. Today we know that the soil of the tropical rainforests is shallow, very poor in nutrients and almost without soluble minerals. Thousands of years of heavy rains have washed away the nutrients in the soil obtained from weathered rocks. The rainforest has a very short nutrient cycle. Nutrients generally stay in an ecosystem by being recycled and in a rainforest are mainly found in the living plants and the layers of decomposing leaf litter. Various species of decomposers like insects, bacteria, and fungi make quick work of turning dead plant and animal matter into nutrients. Plants take up these nutrients the moment they are released. A study in the Amazon rainforest found that 99% of nutrients are held in root mats. When a rainforest is burned or cut down the nutrients are removed from the ecosystem. The soil can only be used for a very short time before it becomes completely depleted of all nutrients.

Besides these four layers, a shrub/sapling layer receives about 3 % of the light that filters in through the canopies. These stunted trees are capable of a sudden growth surge when a gap in the canopy opens above them. The air beneath the lower canopy is almost always humid. The trees themselves give off water through the pores (stomata) of their leaves. This process, called transpiration, can account for as much as half of the precipitation in the rain forest. Rainforest plants have made many adaptations to their environment. With over 80 inches of rain per year, plants have made adaptations that helps them shed water off their leaves quickly so the branches don't get weighed down and break. Many plants have drip tips and grooved leaves, and some leaves have oily coatings to shed water. To absorb as much sunlight as possible on the dark understory, leaves are very large. Some trees have leaf stalks that turn with the movement of the sun so they always absorb the maximum amount of light. Leaves in the upper canopy are dark green, small and leathery to reduce water loss in the strong sunlight. Some trees will grow large leaves at the lower canopy level and small leaves in the upper canopy. Other plants grow in the upper canopy on larger trees to get sunlight. These are the epiphytes such as orchids and bromeliads. Many trees have buttress and stilt roots for extra support in the shallow, wet soil of the rainforests. Over 2,500 species of vines grow in the rainforest. Lianas start off as small shrubs that grow on the forest floor. To reach the sunlight in the upper canopy it sends out tendrils to grab sapling trees. The liana and the tree grow towards the canopy together. The vines grow from one tree to another and make up 40% of the canopy leaves. The rattan vine has spikes on the underside of its leaves that point backwards to grab onto sapling trees. Other "strangler" vines will use trees as support and grow thicker and thicker as they reach the canopy, strangling its host tree. They look like trees whose centers have been hollowed out. Dominant species do not exist in tropical rainforests. Lowland dipterocarp forest can consist of many different species of Dipterocarpaceae, but not all of the same species. Trees of the same species are very seldom found growing close together. This bio diversity and separation of the species prevents mass contamination and die-off from disease or insect infestation. Bio diversity also insures that there will be enough pollinators to take care of each species' needs. Animals depend on the staggered blooming and fruiting of rainforest plants to supply them with a year-round source of food.

There are four very distinct layers of trees in a tropical rain forest. These layers have been identified as the emergent, upper canopy, understory, and forest floor. Emergent trees are spaced wide apart, and are 100 to 240 feet tall with umbrella-shaped canopies that grow above the forest. Because emergent trees are exposed to drying winds, they tend to have small, pointed leaves. Some species lose their leaves during the brief dry season in monsoon rainforests. These giant trees have straight, smooth trunks with few branches. Their root system is very shallow, and to support their size they grow buttresses that can spread out to a distance of 30 feet. The upper canopy of 60 to 130 foot trees allows light to be easily available at the top of this layer, but greatly reduced any light below it. Most of the rainforest's animals live in the upper canopy. There is so much food available at this level that some animals never go down to the forest floor. The leaves have "drip spouts" that allows rain to run off. This keeps them dry and prevents mold and mildew from forming in the humid environment. The understory, or lower canopy, consists of 60 foot trees. This layer is made up of the trunks of canopy trees, shrubs, plants and small trees. There is little air movement. As a result the humidity is constantly high. This level is in constant shade. The forest floor is usually completely shaded, except where a canopy tree has fallen and created an opening. Most areas of the forest floor receive so little light that few bushes or herbs can grow there. As a result, a person can easily walk through most parts of a tropical rain forest. Less than 1 % of the light that strikes the top of the forest penetrates to the forest floor. The top soil is very thin and of poor quality. A lot of litter falls to the ground where it is quickly broken down by decomposers like termites, earthworms and fungi. The heat and humidity further help to break down the litter. This organic matter is then just as quickly absorbed by the trees' shallow roots

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.

Tropical rainforests are home to many kinds of mammals

PRIMATES Bolivian Gray Titi Dusky Titi Monkey Ebony Langur Golden Lion Tamarin Gorilla Lemurs Long-Tailed Macaque Macaque Orangutan Proboscis Monkey Squirrel Monkey Wied's Tufted-Eared Marmoset Woolly Monkey CATS Jaguar Ocelot OTHERS African Forest Buffalo African Forest Buffalo Agouti Babirusa Bat Bearded Pig Capybara Coatimundi Elephant Giant Anteater Giant River Otter Malayan Tapir Okapi Sloth Sumatra Rhino Tapir Wild Boar

Tropical Rainforest Fast Facts Print Fast Facts Description Tropical rainforests are a type of wet, warm, humid forest. Tropical rainforests have the greatest biodiversity of any other ecosystem on earth. Some scientists believe they house more than half of all living species on earth. 90% of the species found in the tropical rainforest live in the canopy, high above the ground. Location Tropical rainforests are located in the tropics, the area around the warm equator. They are found in areas of Africa, Asia, Australia, and South and Central America. Climate The climate of tropical rainforests is warm and humid with almost continual rain. Most rainforests receive 200-1000 cm of rain a year and have temperatures that rarely drop below 22° C. Issues Tropical rainforests are quickly disappearing as a result of logging and clearing for timber, livestock grazing, plantations, and the harvest of other natural resources. 31 million hectares of tropical rainforest are destroyed each year.  That is an area larger than Poland. Status All tropical rainforests are in great danger of being destroyed. They once covered 14% of the earth’s land surface but now only cover 6%. Some scientists believe that, at the current rate of destruction, the remaining forests could be destroyed in less than 40 years. The state of tropical rainforests should be a priority for all countries and cultures since they provide and regulate the majority of the earth’s clean air and water. ©GLOBIO.org

Many of these forests may be too damaged to fully recover," warns one of the researchers, Lisa Curran of the Yale School of Forestry and Environmental Studies, United States. "They are so degraded that the ecological processes of regeneration will be so slow as to be essentially nonexistent." Indonesia contains 10 per cent of the world's tropical rainforest, and it is disappearing even faster than the Brazilian Amazon. Scientists are now calling for action both in Indonesia and abroad to save Borneo's forests, which they say are critical in maintaining the island's biodiversity and sustaining rural livelihoods.

The current rampant destruction of rainforest in Borneo is a biodiversity disaster of planetary proportions. Majestic gifts of creation, which took 50 to 100 million years to develop could be totally decimated in just 50 years of frenzied, largely uncontrolled exploitation

rainforests continue to be destroyed at a pace exceeding 80,000 acres (32,000 hectares) per day.

World rainforest cover now stands at around 2.5 million square miles (6 million square kilometers), an area about the size of the contiguous 48 United States or Australia and representing around 5 percent of the world's land surface. Much of this remaining area has been impacted by human activities and no longer retains its full original biodiversity

They regulate global climate patterns and help mitigate negative effects of climate change, specifically, global climate warming, (Service 1), and They serve as storages of global biodiversity, specifically plant and animal diversity (Service 2). Those are the two main factors that have been widely put forward as the arguments which are strong enough for us people to try to do our utmost to “save the rain forests” from their continuous destruction

For example, the deforestation rate of the Amazon rain forest (the largest tropical fain forest in the world) during 2005–2006 was the lowest since 1991. (18)

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