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Rainforest

Rainforests are characterized by a closed and continuous tree canopy, moisture-dependent vegetation, the presence of epiphytes and lianas and the absence of wildfire. Rainforest can be classified as tropical rainforest or temperate rainforest, but other types have been described.

Rainforest at Kinabalu Park, Borneo
A paranomic view of the Tropical rainforest, Nilgiri mountains, India
Canopy of Khao Sok tropical rainforest
Primitive tropical rainforest in Palawan
The thick rainforest of Chiapas

Estimates vary from 40% to 75% of all biotic species being indigenous to the rainforests.[1] There may be many millions of species of plants, insects and microorganisms still undiscovered in tropical rainforests. Tropical rainforests have been called the "jewels of the Earth" and the "world's largest pharmacy", because over one quarter of natural medicines have been discovered there.[2]

Rainforests as well as endemic rainforest species are rapidly disappearing due to deforestation, the resulting habitat loss and pollution of the atmosphere.[3]

Definition

Rainforest are characterized by a closed and continuous tree canopy, high humidity, the presence of moisture-dependent vegetation, a moist layer of leaf litter, the presence of epiphytes and lianas and the absence of wildfire. The largest areas of rainforest are tropical or temperate rainforests, but other vegetation associations including subtropical rainforest, littoral rainforest, cloud forest, vine thicket and even dry rainforest have been described.[4][5][6][7][8]

Tropical rainforest

 
Location of tropical (dark green) and temperate/subtropical (light green) rainforests in the world.
 
Worldwide tropical rainforest climate zones.

Tropical rainforests are characterized by a warm and wet climate with no substantial dry season: typically found within 10 degrees north and south of the equator. Mean monthly temperatures exceed 18 °C (64 °F) during all months of the year.[9] Average annual rainfall is no less than 168 cm (66 in) and can exceed 1,000 cm (390 in) although it typically lies between 175 cm (69 in) and 200 cm (79 in).[10]

Many of the world's tropical forests are associated with the location of the monsoon trough, also known as the intertropical convergence zone.[11] The broader category of tropical moist forests are located in the equatorial zone between the Tropic of Cancer and Tropic of Capricorn. Tropical rainforests exist in Southeast Asia (from Myanmar (Burma)) to the Philippines, Malaysia, Indonesia, Papua New Guinea and Sri Lanka; also in Sub-Saharan Africa from the Cameroon to the Congo (Congo Rainforest), South America (e.g. the Amazon rainforest), Central America (e.g. Bosawás, the southern Yucatán Peninsula-El Peten-Belize-Calakmul), Australia, and on Pacific Islands (such as Hawaiʻi). Tropical forests have been called the "Earth's lungs", although it is now known that rainforests contribute little net oxygen addition to the atmosphere through photosynthesis.[12][13]

Temperate rainforest

 
General distribution of temperate rainforests
 
Temperate rainforest in Pacific Rim National Park Reserve in Canada

Tropical forests cover a large part of the globe, but temperate rainforests only occur in few regions around the world.[14][15] Temperate rainforests are rainforests in temperate regions. They occur in North America (in the Pacific Northwest in Alaska, British Columbia, Washington, Oregon and California), in Europe (parts of the British Isles such as the coastal areas of Ireland and Scotland, southern Norway, parts of the western Balkans along the Adriatic coast, as well as in Galicia and coastal areas of the eastern Black Sea, including Georgia and coastal Turkey), in East Asia (in southern China, Highlands of Taiwan, much of Japan and Korea, and on Sakhalin Island and the adjacent Russian Far East coast), in South America (southern Chile) and also in Australia and New Zealand.[16]

Dry rainforest

Dry rainforests have a more open canopy layer than other rainforests,[17] and are found in areas of lower rainfall (630–1,100 mm (25–43 in)). They generally have two layers of trees.[18]

Layers

A tropical rainforest typically has a number of layers, each with different plants and animals adapted for life in that particular area. Examples include the emergent, canopy, understory and forest floor layers.[19][20]

Emergent layer

The emergent layer contains a small number of very large trees called emergents, which grow above the general canopy, reaching heights of 45–55 m, although on occasion a few species will grow to 70–80 m tall.[21][22] They need to be able to withstand the hot temperatures and strong winds that occur above the canopy in some areas. Eagles, butterflies, bats and certain monkeys inhabit this layer.

Canopy layer

The canopy layer contains the majority of the largest trees, typically 30 metres (98 ft) to 45 metres (148 ft) tall. The densest areas of biodiversity are found in the forest canopy, a more or less continuous cover of foliage formed by adjacent treetops. The canopy, by some estimates, is home to 50 percent of all plant species. Epiphytic plants attach to trunks and branches, and obtain water and minerals from rain and debris that collects on the supporting plants. The fauna is similar to that found in the emergent layer but more diverse. A quarter of all insect species are believed to exist in the rainforest canopy. Scientists have long suspected the richness of the canopy as a habitat, but have only recently developed practical methods of exploring it. As long ago as 1917, naturalist William Beebe declared that "another continent of life remains to be discovered, not upon the Earth, but one to two hundred feet above it, extending over thousands of square miles." A true exploration of this habitat only began in the 1980s, when scientists developed methods to reach the canopy, such as firing ropes into the trees using crossbows. Exploration of the canopy is still in its infancy, but other methods include the use of balloons and airships to float above the highest branches and the building of cranes and walkways planted on the forest floor. The science of accessing tropical forest canopy using airships or similar aerial platforms is called dendronautics.[23]

Understory layer

The understory or understorey layer lies between the canopy and the forest floor. It is home to a number of birds, snakes and lizards, as well as predators such as jaguars, boa constrictors and leopards. The leaves are much larger at this level and insect life is abundant. Many seedlings that will grow to the canopy level are present in the understory. Only about 5% of the sunlight shining on the rainforest canopy reaches the understory. This layer can be called a shrub layer, although the shrub layer may also be considered a separate layer.

Forest floor

 
Rainforest in the Blue Mountains, Australia

The forest floor, the bottom-most layer, receives only 2% of the sunlight. Only plants adapted to low light can grow in this region. Away from riverbanks, swamps and clearings, where dense undergrowth is found, the forest floor is relatively clear of vegetation because of the low sunlight penetration. It also contains decaying plant and animal matter, which disappears quickly, because the warm, humid conditions promote rapid decay. Many forms of fungi growing here help decay the animal and plant waste.

Flora and fauna

More than half of the world's species of plants and animals are found in rainforests.[24] Rainforests support a very broad array of fauna, including mammals, reptiles, amphibians, birds and invertebrates. Mammals may include primates, felids and other families. Reptiles include snakes, turtles, chameleons and other families; while birds include such families as vangidae and Cuculidae. Dozens of families of invertebrates are found in rainforests. Fungi are also very common in rainforest areas as they can feed on the decomposing remains of plants and animals.

The great diversity in rainforest species is in large part the result of diverse and numerous physical refuges,[25] i.e. places in which plants are inaccessible to many herbivores, or in which animals can hide from predators. Having numerous refuges available also results in much higher total biomass than would otherwise be possible.[26][27]

Some species of fauna show a trend towards declining populations in rainforests, for example, reptiles that feed on amphibians and reptiles. This trend requires close monitoring.[28] The seasonality of rainforests affects the reproductive patterns of amphibians, and this in turn can directly affect the species of reptiles that feed on these groups,[29] particularly species with specialized feeding, since these are less likely to use alternative resources.[30]

Soils

Despite the growth of vegetation in a tropical rainforest, soil quality is often quite poor. Rapid bacterial decay prevents the accumulation of humus. The concentration of iron and aluminium oxides by the laterization process gives the oxisols a bright red colour and sometimes produces mineral deposits such as bauxite. Most trees have roots near the surface because there are insufficient nutrients below the surface; most of the trees' minerals come from the top layer of decomposing leaves and animals. On younger substrates, especially of volcanic origin, tropical soils may be quite fertile. If rainforest trees are cleared, rain can accumulate on the exposed soil surfaces, creating run-off, and beginning a process of soil erosion. Eventually, streams and rivers form and flooding becomes possible. There are several reasons for the poor soil quality. First is that the soil is highly acidic. The roots of plants rely on an acidity difference between the roots and the soil in order to absorb nutrients. When the soil is acidic, there is little difference, and therefore little absorption of nutrients from the soil. Second, the type of clay particles present in tropical rainforest soil has a poor ability to trap nutrients and stop them from washing away. Even if humans artificially add nutrients to the soil, the nutrients mostly wash away and are not absorbed by the plants. Finally, these soils are poor due to the high volume of rain in tropical rainforests washes nutrients out of the soil more quickly than in other climates.[31]

Effect on global climate

A natural rainforest emits and absorbs vast quantities of carbon dioxide. On a global scale, long-term fluxes are approximately in balance, so that an undisturbed rainforest would have a small net impact on atmospheric carbon dioxide levels,[32] though they may have other climatic effects (on cloud formation, for example, by recycling water vapour). No rainforest today can be considered to be undisturbed.[33] Human-induced deforestation plays a significant role in causing rainforests to release carbon dioxide,[34][35][36] as do other factors, whether human-induced or natural, which result in tree death, such as burning and drought.[37] Some climate models operating with interactive vegetation predict a large loss of Amazonian rainforest around 2050 due to drought, forest dieback and the subsequent release of more carbon dioxide.[38]

Human uses

 
Aerial view of the Amazon rainforest, taken from a plane.

Tropical rainforests provide timber as well as animal products such as meat and hides. Rainforests also have value as tourism destinations and for the ecosystem services provided. Many foods originally came from tropical forests, and are still mostly grown on plantations in regions that were formerly primary forest.[39] Also, plant-derived medicines are commonly used for fever, fungal infections, burns, gastrointestinal problems, pain, respiratory problems, and wound treatment.[40] At the same time, rainforests are usually not used sustainably by non-native peoples but are being exploited or removed for agricultural purposes.

Native people

On January 18, 2007, FUNAI reported also that it had confirmed the presence of 67 different uncontacted tribes in Brazil, up from 40 in 2005. With this addition, Brazil has now overtaken the island of New Guinea as the country having the largest number of uncontacted tribes.[41] The province of Irian Jaya or West Papua in the island of New Guinea is home to an estimated 44 uncontacted tribal groups.[42] The tribes are in danger because of the deforestation, especially in Brazil.

Central African rainforest is home of the Mbuti pygmies, one of the hunter-gatherer peoples living in equatorial rainforests characterised by their short height (below one and a half metres, or 59 inches, on average). They were the subject of a study by Colin Turnbull, The Forest People, in 1962.[43] Pygmies who live in Southeast Asia are, amongst others, referred to as “Negrito”. There are many tribes in the rainforests of the Malaysian state of Sarawak. Sarawak is part of Borneo, the third largest island in the world. Some of the other tribes in Sarawak are: the Kayan, Kenyah, Kejaman, Kelabit, Punan Bah, Tanjong, Sekapan, and the Lahanan. Collectively, they are referred to as Dayaks or Orangulu which means "people of the interior".[44]

About half of Sarawak's 1.5 million people are Dayaks. Most Dayaks, it is believed by anthropologists, came originally from the South-East Asian mainland. Their mythologies support this.

Deforestation

 
Satellite photograph of the haze above Borneo and Sumatra, 24 September 2015

Tropical and temperate rainforests have been subjected to heavy legal and illegal logging for their valuable hardwoods and agricultural clearance (slash-and-burn, clearcutting) throughout the 20th century and the area covered by rainforests around the world is shrinking.[45] Biologists have estimated that large numbers of species are being driven to extinction (possibly more than 50,000 a year; at that rate, says E. O. Wilson of Harvard University, a quarter or more of all species on Earth could be exterminated within 50 years)[46] due to the removal of habitat with destruction of the rainforests.

Another factor causing the loss of rainforest is expanding urban areas. Littoral rainforest growing along coastal areas of eastern Australia is now rare due to ribbon development to accommodate the demand for seachange lifestyles.[47]

Forests are being destroyed at a rapid pace.[48][49][50] Almost 90% of West Africa's rainforest has been destroyed.[51] Since the arrival of humans, Madagascar has lost two thirds of its original rainforest.[52] At present rates, tropical rainforests in Indonesia would be logged out in 10 years and Papua New Guinea in 13 to 16 years.[53] According to Rainforest Rescue, an important reason for the increasing deforestation rate, especially in Indonesia, is the expansion of oil palm plantations to meet growing demand for cheap vegetable fats and biofuels. In Indonesia, palm oil is already cultivated on nine million hectares and, together with Malaysia, the island nation produces about 85 percent of the world's palm oil.[54][unreliable source?]

Several countries,[55] notably Brazil, have declared their deforestation a national emergency.[56] Amazon deforestation jumped by 69% in 2008 compared to 2007's twelve months, according to official government data.[57]

However, a January 30, 2009 New York Times article stated, "By one estimate, for every acre of rainforest cut down each year, more than 50 acres of new forest are growing in the tropics." The new forest includes secondary forest on former farmland and so-called degraded forest.[58]

See also

References

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Further reading

 
View of the temperate rain forest in Mount Revelstoke National Park, British Columbia, Canada

.

External links

  • Animals in a rainforest
  • Rainforest Action Network
  • EIA forest reports: Investigations into illegal logging.
  • Reports and info.
  • United Nations Forum on Forests
  • Rainforest Plants
  • Tropical rainforest for children
  • What is a rainforest
  • National Geographic: Rain forest
  • Tropical rainforests

rainforest, other, uses, disambiguation, characterized, closed, continuous, tree, canopy, moisture, dependent, vegetation, presence, epiphytes, lianas, absence, wildfire, classified, tropical, rainforest, temperate, rainforest, other, types, have, been, descri. For other uses see Rainforest disambiguation Rainforests are characterized by a closed and continuous tree canopy moisture dependent vegetation the presence of epiphytes and lianas and the absence of wildfire Rainforest can be classified as tropical rainforest or temperate rainforest but other types have been described Olympic rain forest located at Olympic Peninsula Washington stateRainforest at Kinabalu Park BorneoA paranomic view of the Tropical rainforest Nilgiri mountains IndiaCanopy of Khao Sok tropical rainforestPrimitive tropical rainforest in PalawanRainforests in Pacific Rim National Park ReserveThe thick rainforest of Chiapas Estimates vary from 40 to 75 of all biotic species being indigenous to the rainforests 1 There may be many millions of species of plants insects and microorganisms still undiscovered in tropical rainforests Tropical rainforests have been called the jewels of the Earth and the world s largest pharmacy because over one quarter of natural medicines have been discovered there 2 Rainforests as well as endemic rainforest species are rapidly disappearing due to deforestation the resulting habitat loss and pollution of the atmosphere 3 Contents 1 Definition 1 1 Tropical rainforest 1 2 Temperate rainforest 1 3 Dry rainforest 2 Layers 2 1 Emergent layer 2 2 Canopy layer 2 3 Understory layer 2 4 Forest floor 3 Flora and fauna 4 Soils 5 Effect on global climate 6 Human uses 6 1 Native people 7 Deforestation 8 See also 9 References 10 Further reading 11 External linksDefinitionRainforest are characterized by a closed and continuous tree canopy high humidity the presence of moisture dependent vegetation a moist layer of leaf litter the presence of epiphytes and lianas and the absence of wildfire The largest areas of rainforest are tropical or temperate rainforests but other vegetation associations including subtropical rainforest littoral rainforest cloud forest vine thicket and even dry rainforest have been described 4 5 6 7 8 Tropical rainforest Location of tropical dark green and temperate subtropical light green rainforests in the world Worldwide tropical rainforest climate zones Main article Tropical rainforest Tropical rainforests are characterized by a warm and wet climate with no substantial dry season typically found within 10 degrees north and south of the equator Mean monthly temperatures exceed 18 C 64 F during all months of the year 9 Average annual rainfall is no less than 168 cm 66 in and can exceed 1 000 cm 390 in although it typically lies between 175 cm 69 in and 200 cm 79 in 10 Many of the world s tropical forests are associated with the location of the monsoon trough also known as the intertropical convergence zone 11 The broader category of tropical moist forests are located in the equatorial zone between the Tropic of Cancer and Tropic of Capricorn Tropical rainforests exist in Southeast Asia from Myanmar Burma to the Philippines Malaysia Indonesia Papua New Guinea and Sri Lanka also in Sub Saharan Africa from the Cameroon to the Congo Congo Rainforest South America e g the Amazon rainforest Central America e g Bosawas the southern Yucatan Peninsula El Peten Belize Calakmul Australia and on Pacific Islands such as Hawaiʻi Tropical forests have been called the Earth s lungs although it is now known that rainforests contribute little net oxygen addition to the atmosphere through photosynthesis 12 13 Temperate rainforest General distribution of temperate rainforests Temperate rainforest in Pacific Rim National Park Reserve in Canada Main article Temperate rainforest Tropical forests cover a large part of the globe but temperate rainforests only occur in few regions around the world 14 15 Temperate rainforests are rainforests in temperate regions They occur in North America in the Pacific Northwest in Alaska British Columbia Washington Oregon and California in Europe parts of the British Isles such as the coastal areas of Ireland and Scotland southern Norway parts of the western Balkans along the Adriatic coast as well as in Galicia and coastal areas of the eastern Black Sea including Georgia and coastal Turkey in East Asia in southern China Highlands of Taiwan much of Japan and Korea and on Sakhalin Island and the adjacent Russian Far East coast in South America southern Chile and also in Australia and New Zealand 16 Dry rainforest Dry rainforests have a more open canopy layer than other rainforests 17 and are found in areas of lower rainfall 630 1 100 mm 25 43 in They generally have two layers of trees 18 LayersMain article Stratification vegetation A tropical rainforest typically has a number of layers each with different plants and animals adapted for life in that particular area Examples include the emergent canopy understory and forest floor layers 19 20 Emergent layer The emergent layer contains a small number of very large trees called emergents which grow above the general canopy reaching heights of 45 55 m although on occasion a few species will grow to 70 80 m tall 21 22 They need to be able to withstand the hot temperatures and strong winds that occur above the canopy in some areas Eagles butterflies bats and certain monkeys inhabit this layer Canopy layer Main article Canopy biology The canopy at the Forest Research Institute Malaysia showing crown shyness The canopy layer contains the majority of the largest trees typically 30 metres 98 ft to 45 metres 148 ft tall The densest areas of biodiversity are found in the forest canopy a more or less continuous cover of foliage formed by adjacent treetops The canopy by some estimates is home to 50 percent of all plant species Epiphytic plants attach to trunks and branches and obtain water and minerals from rain and debris that collects on the supporting plants The fauna is similar to that found in the emergent layer but more diverse A quarter of all insect species are believed to exist in the rainforest canopy Scientists have long suspected the richness of the canopy as a habitat but have only recently developed practical methods of exploring it As long ago as 1917 naturalist William Beebe declared that another continent of life remains to be discovered not upon the Earth but one to two hundred feet above it extending over thousands of square miles A true exploration of this habitat only began in the 1980s when scientists developed methods to reach the canopy such as firing ropes into the trees using crossbows Exploration of the canopy is still in its infancy but other methods include the use of balloons and airships to float above the highest branches and the building of cranes and walkways planted on the forest floor The science of accessing tropical forest canopy using airships or similar aerial platforms is called dendronautics 23 Understory layer Main article Understory The understory or understorey layer lies between the canopy and the forest floor It is home to a number of birds snakes and lizards as well as predators such as jaguars boa constrictors and leopards The leaves are much larger at this level and insect life is abundant Many seedlings that will grow to the canopy level are present in the understory Only about 5 of the sunlight shining on the rainforest canopy reaches the understory This layer can be called a shrub layer although the shrub layer may also be considered a separate layer Forest floor Main article Forest floor Rainforest in the Blue Mountains Australia The forest floor the bottom most layer receives only 2 of the sunlight Only plants adapted to low light can grow in this region Away from riverbanks swamps and clearings where dense undergrowth is found the forest floor is relatively clear of vegetation because of the low sunlight penetration It also contains decaying plant and animal matter which disappears quickly because the warm humid conditions promote rapid decay Many forms of fungi growing here help decay the animal and plant waste Flora and faunaMore than half of the world s species of plants and animals are found in rainforests 24 Rainforests support a very broad array of fauna including mammals reptiles amphibians birds and invertebrates Mammals may include primates felids and other families Reptiles include snakes turtles chameleons and other families while birds include such families as vangidae and Cuculidae Dozens of families of invertebrates are found in rainforests Fungi are also very common in rainforest areas as they can feed on the decomposing remains of plants and animals The great diversity in rainforest species is in large part the result of diverse and numerous physical refuges 25 i e places in which plants are inaccessible to many herbivores or in which animals can hide from predators Having numerous refuges available also results in much higher total biomass than would otherwise be possible 26 27 A Kermode bear from the Great Bear Rainforest Canada A Bengal tiger in Mudumalai National Park India A jaguar in the Amazon Rainforest South America Western lowland gorilla in the African rainforest Yellow anacondas reside in the Amazon basin Lion tailed macaque in Silent Valley National Park India A Macaw in the Amazon rainforestSome species of fauna show a trend towards declining populations in rainforests for example reptiles that feed on amphibians and reptiles This trend requires close monitoring 28 The seasonality of rainforests affects the reproductive patterns of amphibians and this in turn can directly affect the species of reptiles that feed on these groups 29 particularly species with specialized feeding since these are less likely to use alternative resources 30 SoilsThis section needs additional citations for verification Please help improve this article by adding citations to reliable sources Unsourced material may be challenged and removed February 2020 Learn how and when to remove this template message Despite the growth of vegetation in a tropical rainforest soil quality is often quite poor Rapid bacterial decay prevents the accumulation of humus The concentration of iron and aluminium oxides by the laterization process gives the oxisols a bright red colour and sometimes produces mineral deposits such as bauxite Most trees have roots near the surface because there are insufficient nutrients below the surface most of the trees minerals come from the top layer of decomposing leaves and animals On younger substrates especially of volcanic origin tropical soils may be quite fertile If rainforest trees are cleared rain can accumulate on the exposed soil surfaces creating run off and beginning a process of soil erosion Eventually streams and rivers form and flooding becomes possible There are several reasons for the poor soil quality First is that the soil is highly acidic The roots of plants rely on an acidity difference between the roots and the soil in order to absorb nutrients When the soil is acidic there is little difference and therefore little absorption of nutrients from the soil Second the type of clay particles present in tropical rainforest soil has a poor ability to trap nutrients and stop them from washing away Even if humans artificially add nutrients to the soil the nutrients mostly wash away and are not absorbed by the plants Finally these soils are poor due to the high volume of rain in tropical rainforests washes nutrients out of the soil more quickly than in other climates 31 Effect on global climateA natural rainforest emits and absorbs vast quantities of carbon dioxide On a global scale long term fluxes are approximately in balance so that an undisturbed rainforest would have a small net impact on atmospheric carbon dioxide levels 32 though they may have other climatic effects on cloud formation for example by recycling water vapour No rainforest today can be considered to be undisturbed 33 Human induced deforestation plays a significant role in causing rainforests to release carbon dioxide 34 35 36 as do other factors whether human induced or natural which result in tree death such as burning and drought 37 Some climate models operating with interactive vegetation predict a large loss of Amazonian rainforest around 2050 due to drought forest dieback and the subsequent release of more carbon dioxide 38 Human uses Aerial view of the Amazon rainforest taken from a plane Further information Tropical rainforest Human dimensions Tropical rainforests provide timber as well as animal products such as meat and hides Rainforests also have value as tourism destinations and for the ecosystem services provided Many foods originally came from tropical forests and are still mostly grown on plantations in regions that were formerly primary forest 39 Also plant derived medicines are commonly used for fever fungal infections burns gastrointestinal problems pain respiratory problems and wound treatment 40 At the same time rainforests are usually not used sustainably by non native peoples but are being exploited or removed for agricultural purposes Native people On January 18 2007 FUNAI reported also that it had confirmed the presence of 67 different uncontacted tribes in Brazil up from 40 in 2005 With this addition Brazil has now overtaken the island of New Guinea as the country having the largest number of uncontacted tribes 41 The province of Irian Jaya or West Papua in the island of New Guinea is home to an estimated 44 uncontacted tribal groups 42 The tribes are in danger because of the deforestation especially in Brazil Central African rainforest is home of the Mbuti pygmies one of the hunter gatherer peoples living in equatorial rainforests characterised by their short height below one and a half metres or 59 inches on average They were the subject of a study by Colin Turnbull The Forest People in 1962 43 Pygmies who live in Southeast Asia are amongst others referred to as Negrito There are many tribes in the rainforests of the Malaysian state of Sarawak Sarawak is part of Borneo the third largest island in the world Some of the other tribes in Sarawak are the Kayan Kenyah Kejaman Kelabit Punan Bah Tanjong Sekapan and the Lahanan Collectively they are referred to as Dayaks or Orangulu which means people of the interior 44 About half of Sarawak s 1 5 million people are Dayaks Most Dayaks it is believed by anthropologists came originally from the South East Asian mainland Their mythologies support this DeforestationFurther information Deforestation in Southeast Asia Deforestation in Madagascar and Deforestation of the Amazon Rainforest Satellite photograph of the haze above Borneo and Sumatra 24 September 2015 Tropical and temperate rainforests have been subjected to heavy legal and illegal logging for their valuable hardwoods and agricultural clearance slash and burn clearcutting throughout the 20th century and the area covered by rainforests around the world is shrinking 45 Biologists have estimated that large numbers of species are being driven to extinction possibly more than 50 000 a year at that rate says E O Wilson of Harvard University a quarter or more of all species on Earth could be exterminated within 50 years 46 due to the removal of habitat with destruction of the rainforests Another factor causing the loss of rainforest is expanding urban areas Littoral rainforest growing along coastal areas of eastern Australia is now rare due to ribbon development to accommodate the demand for seachange lifestyles 47 Forests are being destroyed at a rapid pace 48 49 50 Almost 90 of West Africa s rainforest has been destroyed 51 Since the arrival of humans Madagascar has lost two thirds of its original rainforest 52 At present rates tropical rainforests in Indonesia would be logged out in 10 years and Papua New Guinea in 13 to 16 years 53 According to Rainforest Rescue an important reason for the increasing deforestation rate especially in Indonesia is the expansion of oil palm plantations to meet growing demand for cheap vegetable fats and biofuels In Indonesia palm oil is already cultivated on nine million hectares and together with Malaysia the island nation produces about 85 percent of the world s palm oil 54 unreliable source Several countries 55 notably Brazil have declared their deforestation a national emergency 56 Amazon deforestation jumped by 69 in 2008 compared to 2007 s twelve months according to official government data 57 However a January 30 2009 New York Times article stated By one estimate for every acre of rainforest cut down each year more than 50 acres of new forest are growing in the tropics The new forest includes secondary forest on former farmland and so called degraded forest 58 See also Environment portal Ecology portalCloud forest Ecology Inland rainforest Intact forest landscape Jungle Rainforest Foundation Fund Sepilok Orang Utan Sanctuary Stratification vegetation Tapiche Ohara s ReserveReferences Rainforests net Variables and Math Archived from the original on 2008 12 05 Retrieved 2009 01 04 Rainforests at Animal Center Animalcorner co uk 2004 01 01 Archived from the original on 2012 07 08 Retrieved 2012 08 26 Impact of Deforestation Extinction Rainforests mongabay com Retrieved 2012 08 26 Rainforests Wet Tropics Management Authority Retrieved 9 July 2021 Rainforests The State of Queensland Retrieved 9 July 2021 Rainforests New South Wales Government Office of Environment and heritage Retrieved 9 July 2021 Dry Rainforest Tasmanian Government Department of Primary Industries Parks Water and Environment Retrieved 9 July 2021 Western Sydney Dry Rainforest PDF New South Wales Government Department of Planning Industry and Environment Retrieved 9 July 2021 Susan Woodward Tropical broadleaf Evergreen Forest The rainforest Archived 2008 02 25 at the Wayback Machine Retrieved on 2008 03 14 Newman Arnold The Tropical Rainforest A World Survey of Our Most Valuable Endangered Habitat With a Blueprint for Its Survival New York Checkmark 2002 Print Hobgood 2008 Global Pattern of Surface Pressure and Wind Archived 2009 03 18 at the Wayback Machine Ohio State University Retrieved on 2009 03 08 Broeker Wallace S 2006 Breathing easy Et tu O2 Columbia University Columbia edu Moran Emilio F 1993 Deforestation and land use in the Brazilian Amazon Human Ecology 21 1 21 doi 10 1007 BF00890069 S2CID 153481315 Link Timothy E Unsworth Mike Marks Danny August 2004 The dynamics of rainfall interception by a seasonal temperate rainforest Agricultural and Forest Meteorology 124 3 4 171 191 Bibcode 2004AgFM 124 171L doi 10 1016 j agrformet 2004 01 010 Cunningham S C Read J January 2003 Do temperate rainforest trees have a greater ability to acclimate to changing temperatures than tropical rainforest trees New Phytologist 157 1 55 64 doi 10 1046 j 1469 8137 2003 00652 x PMID 33873691 The Temperate Rainforest Coleby Williams Jerry 2020 Kumbartcho Dry Rainforest Gardening Australia ABC Retrieved 6 May 2022 Identification of Rainforest Field Guide PDF Department of Environment and Conservation NSW Government 2004 Retrieved 6 May 2022 Denslow J S November 1987 Tropical Rainforest Gaps and Tree Species Diversity Annual Review of Ecology and Systematics 18 1 431 451 doi 10 1146 annurev es 18 110187 002243 Webb Len 1 Oct 1959 A Physiognomic Classification of Australian Rain Forests Journal of Ecology British Ecological Society Journal of Ecology Vol 47 No 3 pp 551 570 47 3 551 570 doi 10 2307 2257290 JSTOR 2257290 Bourgeron Patrick S 1983 Spatial Aspects of Vegetation Structure In Frank B Golley ed Tropical Rain Forest Ecosystems Structure and Function Ecosystems of the World 14A ed Elsevier Scientific pp 29 47 ISBN 0 444 41986 1 Sabah Eastern Native Tree Society Retrieved 2007 11 14 dendronautics Archived from the original on June 14 2006 Rainforest Facts Rain tree com Retrieved 2012 08 26 Ritchie Euan G Johnson Christopher N September 2009 Predator interactions mesopredator release and biodiversity conservation Ecology Letters 12 9 982 998 doi 10 1111 j 1461 0248 2009 01347 x PMID 19614756 S2CID 11744558 Sih Andrew 1987 Prey refuges and predator prey stability Theoretical Population Biology 31 1 12 doi 10 1016 0040 5809 87 90019 0 McNair James N 1986 The effects of refuges on predator prey interactions A reconsideration Theoretical Population Biology 29 1 38 63 doi 10 1016 0040 5809 86 90004 3 PMID 3961711 Barquero Gonzalez J P Stice T L Gomez G amp Monge Najera J 2020 Are tropical reptiles really declining A six year survey of snakes in a tropical coastal rainforest role of prey and environment Revista de Biologia Tropical 68 1 336 343 Oliveira M E amp Martins M 2001 When and where to find a pitviper activity patterns and habitat use of the lancehead Bothrops atrox in central Amazonia Brazil Herpetological Natural History 8 2 101 110 Terborgh J amp Winter B 1980 Some causes of extinction Conservation Biology 2 119 133 Baird Dr Chris S What makes the soil in tropical rainforests so rich Science Questions with Surprising Answers Retrieved 11 April 2019 Grida no PDF Retrieved 2012 08 26 Lewis S L Phillips O L Baker T R Lloyd J Malhi Y Almeida S Higuchi N Laurance W F Neill D A Silva J N M Terborgh J Torres Lezama A Vasquez Martinez R Brown S Chave J Kuebler C Nunez Vargas P Vinceti B 29 March 2004 Concerted changes in tropical forest structure and dynamics evidence from 50 South American long term plots Philosophical Transactions of the Royal Society of London Series B Biological Sciences 359 1443 421 436 doi 10 1098 rstb 2003 1431 PMC 1693337 PMID 15212094 Malhi Yadvinder Grace John August 2000 Tropical forests and atmospheric carbon dioxide Trends in Ecology amp Evolution 15 8 332 337 doi 10 1016 s0169 5347 00 01906 6 PMID 10884705 Cramer Wolfgang Bondeau Alberte Schaphoff Sibyll Lucht Wolfgang Smith Ben Sitch Stephen 2005 Twenty first century atmospheric change and deforestation Potential impacts on tropical forests Tropical Forests and Global Atmospheric Change Oxford University Press pp 17 30 doi 10 1093 acprof oso 9780198567066 003 0002 ISBN 978 0 19 856706 6 Baccini A Walker W Carvalho L Farina M Sulla Menashe D Houghton R A 13 October 2017 Tropical forests are a net carbon source based on aboveground measurements of gain and loss Science 358 6360 230 234 Bibcode 2017Sci 358 230B doi 10 1126 science aam5962 PMID 28971966 Drought may turn forests into carbon producers The Age Melbourne 2004 03 06 Cox P M Betts R A Collins M Harris P P Huntingford C Jones C D June 2004 Amazonian forest dieback under climate carbon cycle projections for the 21st century Theoretical and Applied Climatology 78 1 3 137 Bibcode 2004ThApC 78 137C doi 10 1007 s00704 004 0049 4 S2CID 5122043 Myers N 1985 The primary source W W Norton amp Company New York pp 189 193 Final Paper The Medicinal Value of the Rainforest May 15 2003 Amanda Haidet May 2003 Jrscience wcp muohio edu Retrieved 2012 08 26 Brazil sees traces of more isolated Amazon tribes Reuters com 2007 01 17 Retrieved 2012 08 26 BBC First contact with isolated tribes SurvivalInternational org 2007 01 25 Archived from the original on 2008 02 06 Retrieved 2020 05 13 The Tribal Peoples Archived 2012 10 20 at the Wayback Machine ThinkQuest Indigenous People of the Rainforest Rainforest Information Centre Educational Supplement Retrieved 11 April 2019 Entire rainforests set to disappear in next decade The Independent 5 July 2003 Stevens William K 3 March 1992 Talks Seek to Prevent Huge Loss of Species The New York Times Littoral Rainforest Why is it threatened Pittwater nsw gov au 2012 08 09 Retrieved 2012 08 26 Feng Yu Zeng Zhenzhong Searchinger Timothy D Ziegler Alan D Wu Jie Wang Dashan He Xinyue Elsen Paul R Ciais Philippe Xu Rongrong Guo Zhilin 2022 02 28 Doubling of annual forest carbon loss over the tropics during the early twenty first century Nature Sustainability 5 5 444 451 doi 10 1038 s41893 022 00854 3 ISSN 2398 9629 S2CID 247160560 Brazil Amazon Forest Destruction Rate Has Tripled FoxNews com September 29 2008 Papua New Guinea s rainforests disappearing faster than thought News mongabay com Archived from the original on 2008 06 08 Retrieved 2012 08 26 Rainforests amp Agriculture Csupomona edu Archived from the original on 2012 09 30 Retrieved 2012 08 26 Science Satellite monitors Madagascar s shrinking rainforest 19 May 1990 New Scientist Newscientist com 1990 05 19 Retrieved 2012 08 26 China is black hole of Asia s deforestation AsiaNews it 24 March 2008 Palm oil deforestation for everyday products Rainforest Rescue www rainforest rescue org Amazon deforestation rises sharply in 2007 Usatoday com January 24 2008 Vidal John 20 May 2005 Rainforest loss shocks Brazil guardian co uk London Retrieved 7 July 2010 Brazil admits Amazon deforestation on the rise NBC News The Associated Press 30 August 2008 Rosenthal Elisabeth 30 January 2009 New Jungles Prompt a Debate on Rain Forests The New York Times Further reading View of the temperate rain forest in Mount Revelstoke National Park British Columbia Canada Butler R A 2005 A Place Out of Time Tropical Rainforests and the Perils They Face Published online Rainforests mongabay com Richards P W 1996 The tropical rain forest 2nd ed Cambridge University Press ISBN 0 521 42194 2 Whitmore T C 1998 An introduction to tropical rain forests 2nd ed Oxford University Press ISBN 0 19 850147 1External links Wikimedia Commons has media related to Rainforest Look up rainforest in Wiktionary the free dictionary Animals in a rainforest Rainforest Action Network EIA forest reports Investigations into illegal logging EIA in the USA Reports and info The Coalition for Rainforest Nations United Nations Forum on Forests Dave Kimble s Rainforest Photo Catalog Wet Tropics Australia Rainforest Plants Tropical rainforest for children What is a rainforest National Geographic Rain forest Tropical rainforests Retrieved from https en wikipedia org w index php title Rainforest amp oldid 1133338230, wikipedia, wiki, book, books, library,

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