The
Amazon Rainforest (in
PortugueseBrazilian Portuguese is a group of Portuguese dialects written and spoken by most of the 190 million inhabitants of Brazil and by a few million Brazilian emigrants, mainly in the United States, United Kingdom, Portugal, Canada, Japan and Paraguay....
,
Floresta Amazônica or
Amazônia;
SpanishSpanish , also known as Castilian , is a Romance language in the Ibero-Romance group that evolved from several languages and dialects in central-northern Iberia around the 9th century and gradually spread with the expansion of the Kingdom of Castile into central and southern Iberia during the...
Selva Amazónica,
Amazonía or usually
Amazonia), also known in English as
Amazonia or the
Amazon Jungle, is a
moist broadleaf forestTropical and subtropical moist broadleaf forests , also known as tropical moist forests, are a tropical and subtropical forest biome....
that covers most of the
Amazon BasinThe Amazon Basin is the part of South America drained by the Amazon River and its tributaries that drains an area of about , or roughly 40 percent of South America. The basin is located in the countries of Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru, and Venezuela...
of South America. This basin encompasses seven million square kilometers (1.7 billion acres), of which five and a half million square kilometers (1.4 billion acres) are covered by the rainforest. This region includes territory belonging to nine nations. The majority of the forest is contained within Brazil, with 60% of the rainforest, followed by
PeruThe Peruvian Amazon is the area of the Amazon jungle included in the territory of Peru, from the east of the Andes to borders with Ecuador, Colombia, Brazil and Bolivia. This region comprises 60% of the country and is marked by a large degree of biodiversity...
with 13%, and with minor amounts in Colombia, Venezuela, Ecuador, Bolivia, Guyana, Suriname and France (
French GuianaFrench Guiana is an overseas region of France, consisting of a single overseas department located on the northern Atlantic coast of South America. It has borders with two nations, Brazil to the east and south, and Suriname to the west...
). States or departments in four nations bear the name Amazonas after it. The Amazon represents over half of the planet's remaining
rainforestRainforests are forests characterized by high rainfall, with definitions based on a minimum normal annual rainfall of 1750-2000 mm...
s, and it comprises the largest and most species-rich tract of
tropical rainforestA tropical rainforest is an ecosystem type that occurs roughly within the latitudes 28 degrees north or south of the equator . This ecosystem experiences high average temperatures and a significant amount of rainfall...
in the world.
The Amazon rainforest was short-listed in 2008 as a candidate to be one of the New7Wonders of Nature by the
New Seven Wonders of the WorldNew7Wonders of the World was an initiative started in 2001 by the Swiss corporation New7Wonders Foundation to choose Wonders of the World from a selection of 200 existing monuments. A popularity poll was led by Canadian-Swiss Bernard Weber and organized by the New7Wonders Foundation based in...
Foundation. As of February 2009 the Amazon was ranking first in Group E, the category for forests, national parks and nature reserves.
Etymology
The name
Amazon is said to arise from a war
Francisco de OrellanaFrancisco de Orellana was a Spanish explorer and conquistador. He completed the first known navigation of the length of the Amazon River, which was originally named for him...
fought with a tribe of Tapuyas and other tribes from South America. The women of the tribe fought alongside the men, as was the custom among the entire tribe. Orellana derived the name Amazonas from the ancient
AmazonsThe Amazons are a nation of all-female warriors in Greek mythology and Classical antiquity. Herodotus placed them in a region bordering Scythia in Sarmatia...
of Asia and Africa described by
HerodotusHerodotus was an ancient Greek historian who was born in Halicarnassus, Caria and lived in the 5th century BC . He has been called the "Father of History", and was the first historian known to collect his materials systematically, test their accuracy to a certain extent and arrange them in a...
and
DiodorusDiodorus Siculus was a Greek historian who flourished between 60 and 30 BC. According to Diodorus' own work, he was born at Agyrium in Sicily . With one exception, antiquity affords no further information about Diodorus' life and doings beyond what is to be found in his own work, Bibliotheca...
in
GreekAncient Greece is a civilization belonging to a period of Greek history that lasted from the Archaic period of the 8th to 6th centuries BC to the end of antiquity. Immediately following this period was the beginning of the Early Middle Ages and the Byzantine era. Included in Ancient Greece is the...
legends.
History
The rainforest likely formed during the
EoceneThe Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...
era. It appeared following a global reduction of tropical temperatures when the Atlantic Ocean had widened sufficiently to provide a warm, moist climate to the Amazon basin. The rain forest has been in existence for at least 55 million years, and most of the region remained free of
savannaA savanna, or savannah, is a grassland ecosystem characterized by the trees being sufficiently small or widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of C4 grasses.Some...
-type
biomeBiomes are climatically and geographically defined as similar climatic conditions on the Earth, such as communities of plants, animals, and soil organisms, and are often referred to as ecosystems. Some parts of the earth have more or less the same kind of abiotic and biotic factors spread over a...
s at least until the current ice age, when the climate was drier and savanna more widespread.
Following the Cretaceous–Tertiary extinction event, the extinction of the
dinosaurDinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...
s and the wetter climate may have allowed the tropical rainforest to spread out across the continent. From 65–34 Mya, the rainforest extended as far south as
45°The 45th parallel south is a circle of latitude that is 45 degrees south of the Earth's equatorial plane. It is the line that marks the theoretical halfway point between the equator and the South Pole...
. Climate fluctuations during the last 34 million years have allowed savanna regions to expand into the tropics. During the
OligoceneThe Oligocene is a geologic epoch of the Paleogene Period and extends from about 34 million to 23 million years before the present . As with other older geologic periods, the rock beds that define the period are well identified but the exact dates of the start and end of the period are slightly...
, for example, the rainforest spanned a relatively narrow band that lay mostly above latitude
15°NThe 15th parallel north is a circle of latitude that is 15 degrees north of the Earth's equatorial plane. It crosses Africa, Asia, the Indian Ocean, the Pacific Ocean, Central America, the Caribbean and the Atlantic Ocean....
. It expanded again during the
Middle MioceneThe Middle Miocene is a sub-epoch of the Miocene Epoch made up of two stages: the Langhian and Serravallian stages. The Middle Miocene is preceded by the Early Miocene....
, then retracted to a mostly inland formation at the last glacial maximum. However, the rainforest still managed to thrive during these glacial periods, allowing for the survival and evolution of a broad diversity of species.
During the mid-Eocene, it is believed that the drainage basin of the Amazon was split along the middle of the continent by the Purus Arch. Water on the eastern side flowed toward the Atlantic, while to the west water flowed toward the
PacificThe Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
across the Amazonas Basin. As the
AndesThe Andes is the world's longest continental mountain range. It is a continual range of highlands along the western coast of South America. This range is about long, about to wide , and of an average height of about .Along its length, the Andes is split into several ranges, which are separated...
Mountains rose, however, a large basin was created that enclosed a lake; now known as the Solimões Basin. Within the last 5–10 million years, this accumulating water broke through the Purus Arch, joining the easterly flow toward the Atlantic.
There is evidence that there have been significant changes in Amazon rainforest vegetation over the last 21,000 years through the
Last Glacial MaximumThe Last Glacial Maximum refers to a period in the Earth's climate history when ice sheets were at their maximum extension, between 26,500 and 19,000–20,000 years ago, marking the peak of the last glacial period. During this time, vast ice sheets covered much of North America, northern Europe and...
(LGM) and subsequent deglaciation. Analyses of sediment deposits from Amazon basin paleolakes and from the Amazon Fan indicate that rainfall in the basin during the LGM was lower than for the present, and this was almost certainly associated with reduced moist tropical vegetation cover in the basin. There is debate, however, over how extensive this reduction was. Some scientists argue that the rainforest was reduced to small, isolated refugia separated by open forest and grassland; other scientists argue that the rainforest remained largely intact but extended less far to the north, south, and east than is seen today. This debate has proved difficult to resolve because the practical limitations of working in the rainforest mean that data sampling is biased away from the center of the Amazon basin, and both explanations are reasonably well supported by the available data.
Based on archaeological evidence from an excavation at Caverna da Pedra Pintada, human inhabitants first settled in the Amazon region at least 11,200 years ago. Subsequent development led to late-prehistoric settlements along the periphery of the forest by 1250 AD, which induced alterations in the forest cover. Biologists believe that a population density of 0.2 PD/km2 is the maximum that can be sustained in the rain forest through hunting. Hence, agriculture is needed to host a larger population.
Some 5 to 7 million people lived in the Amazon region, divided between dense coastal settlements, such as that at
MarajóThe Marajoara or Marajó culture was a pre-Columbian era society that flourished on Marajó island at the mouth of the Amazon River. In a survey, Mann suggests dates between 800 AD and 1400 AD for the culture, while other research posits activity two centuries earlier and persistence two centuries...
, and inland dwellers. For a long time, it was believed that those inland dwellers were sparsely populated hunter-gatherer tribes. Archeologist Betty J. Meggers was a prominent proponent of this idea, as described in her book
Amazonia: Man and Culture in a Counterfeit Paradise. However, recent archeological findings have suggested that the region was actually densely populated.
One of the main pieces of evidence is the existence of the fertile
Terra pretaTerra preta is a type of very dark, fertile anthropogenic soil found in the Amazon Basin. Terra preta owes its name to its very high charcoal content, and was indeed made by adding a mixture of charcoal, bone, and manure to the otherwise relatively infertile Amazonian soil, and stays there for...
(black earth), which is distributed over large areas in the Amazon forest. It is now widely accepted that these soils are a product of indigenous soil management. The development of this soil allowed
agricultureAgriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...
and
silvicultureSilviculture is the practice of controlling the establishment, growth, composition, health, and quality of forests to meet diverse needs and values. The name comes from the Latin silvi- + culture...
in the previously hostile environment; meaning that large portions of the Amazon rainforest are probably the result of centuries of human management, rather than naturally occurring as has previously been supposed. In the region of the Xinguanos tribe, remains of some of these large settlements in the middle of the Amazon forest were found in 2003 by Michael Heckenberger and colleagues of the
University of FloridaThe University of Florida is an American public land-grant, sea-grant, and space-grant research university located on a campus in Gainesville, Florida. The university traces its historical origins to 1853, and has operated continuously on its present Gainesville campus since September 1906...
. Among those were evidence of roads, bridges and large plazas.
The first European to travel the length of the
Amazon RiverThe Amazon of South America is the second longest river in the world and by far the largest by waterflow with an average discharge greater than the next seven largest rivers combined...
was
Francisco de OrellanaFrancisco de Orellana was a Spanish explorer and conquistador. He completed the first known navigation of the length of the Amazon River, which was originally named for him...
in 1542.
Biodiversity
Wet tropical forests are the most species-rich
biomeBiomes are climatically and geographically defined as similar climatic conditions on the Earth, such as communities of plants, animals, and soil organisms, and are often referred to as ecosystems. Some parts of the earth have more or less the same kind of abiotic and biotic factors spread over a...
, and tropical forests in the Americas are consistently more species rich than the wet forests in Africa and Asia. As the largest tract of tropical rainforest in the Americas, the Amazonian rainforests have unparalleled
biodiversityBiodiversity is the degree of variation of life forms within a given ecosystem, biome, or an entire planet. Biodiversity is a measure of the health of ecosystems. Biodiversity is in part a function of climate. In terrestrial habitats, tropical regions are typically rich whereas polar regions...
. One in ten known species in the world lives in the Amazon Rainforest. This constitutes the largest collection of living plants and animal species in the world.
The region is home to about 2.5 million
insectThe Amazon Rainforest and surrounding region is the most biodiverse on earth and no life form is more diverse than the insects of the Amazon. No one can put any accurate figure on how many species there are but it has been estimated to be around 30 million, with 700 species of beetle discovered on...
speciesIn biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
, tens of thousands of plants, and some 2,000 birds and
mammalMammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
s. To date, at least 40,000 plant species, 2,200
fishesThe freshwater fishes of tropical South and Central America represent one of the most diverse aquatic ecosystems on Earth, with more than 5,600 species, representing about 10% all living vertebrate species...
, 1,294 birds, 427 mammals, 428 amphibians, and 378 reptiles have been scientifically classified in the region. One in five of all the bird species in the world live in the rainforests of the Amazon, and one in five of the fish species live in Amazonian rivers and streams. Scientists have described between 96,660 and 128,843
invertebrateAn invertebrate is an animal without a backbone. The group includes 97% of all animal species – all animals except those in the chordate subphylum Vertebrata .Invertebrates form a paraphyletic group...
species in Brazil alone.
The diversity of plant species is the highest on Earth with some experts estimating that one square kilometer (247 acres) may contain more than a thousand types of trees and thousands of species of other higher plants. According to a 2001 study, a quarter square kilometer (62 acres) of Ecuadorian rainforest supports more than 1,100 tree species.
One square kilometer (247 acres) of Amazon rainforest can contain about 90,790 tonnes of living plants. The average plant biomass is estimated at 356 ± 47 tonnes per hectare. To date, an estimated 438,000 species of plants of economic and social interest have been registered in the region with many more remaining to be discovered or catalogued.
The green leaf area of plants and trees in the rainforest varies by about 25% as a result of seasonal changes. Leaves expand during the dry season when sunlight is at a maximum, then undergo abscission in the cloudy wet season. These changes provide a balance of carbon between photosynthesis and respiration.
The rainforest contains several species that can pose a hazard. Among the largest predatory creatures are the
black caimanThe black caiman is a crocodilian. It is a carnivorous reptile that lives along slow-moving rivers and lakes, in the seasonally flooded savannas of the Amazon basin, and in other freshwater habitats in South America. Once common, it was hunted to near extinction primarily for its commercially...
,
jaguarThe jaguar is a big cat, a feline in the Panthera genus, and is the only Panthera species found in the Americas. The jaguar is the third-largest feline after the tiger and the lion, and the largest in the Western Hemisphere. The jaguar's present range extends from Southern United States and Mexico...
, cougar, and
anacondaAn anaconda is a large, non-venomous snake found in tropical South America. Although the name actually applies to a group of snakes, it is often used to refer only to one species in particular, the common or green anaconda, Eunectes murinus, which is one of the largest snakes in the world.Anaconda...
. In the river,
electric eelThe electric eel , is an electric fish, and the only species of the genus Electrophorus. It is capable of generating powerful electric shocks, of up to six hundred volts, which it uses for both hunting and self-defense. It is an apex predator in its South American range...
s can produce an electric shock that can stun or kill, while
piranhaA piranha or piraña is a member of family Characidae in order Characiformes, an omnivorous freshwater fish that inhabits South American rivers. In Venezuela, they are called caribes...
are known to bite and injure humans. Various species of
poison dart frogPoison dart frog is the common name of a group of frogs in the family Dendrobatidae which are native to Central and South America. These species are diurnal and often have brightly-colored bodies...
s secrete
lipophilicLipophilicity, , refers to the ability of a chemical compound to dissolve in fats, oils, lipids, and non-polar solvents such as hexane or toluene. These non-polar solvents are themselves lipophilic — the axiom that like dissolves like generally holds true...
alkaloidAlkaloids are a group of naturally occurring chemical compounds that contain mostly basic nitrogen atoms. This group also includes some related compounds with neutral and even weakly acidic properties. Also some synthetic compounds of similar structure are attributed to alkaloids...
toxins through their flesh. There are also numerous parasites and disease vectors.
Vampire batVampire bats are bats whose food source is blood, a dietary trait called hematophagy. There are three bat species that feed solely on blood: the Common Vampire Bat , the Hairy-legged Vampire Bat , and the White-winged Vampire Bat .All three species are native to the Americas, ranging from Mexico to...
s dwell in the rainforest and can spread the
rabiesRabies is a viral disease that causes acute encephalitis in warm-blooded animals. It is zoonotic , most commonly by a bite from an infected animal. For a human, rabies is almost invariably fatal if post-exposure prophylaxis is not administered prior to the onset of severe symptoms...
virus.
MalariaMalaria is a mosquito-borne infectious disease of humans and other animals caused by eukaryotic protists of the genus Plasmodium. The disease results from the multiplication of Plasmodium parasites within red blood cells, causing symptoms that typically include fever and headache, in severe cases...
,
yellow feverYellow fever is an acute viral hemorrhagic disease. The virus is a 40 to 50 nm enveloped RNA virus with positive sense of the Flaviviridae family....
and
Dengue feverDengue fever , also known as breakbone fever, is an infectious tropical disease caused by the dengue virus. Symptoms include fever, headache, muscle and joint pains, and a characteristic skin rash that is similar to measles...
can also be contracted in the Amazon region.
Deforestation
DeforestationDeforestation is the removal of a forest or stand of trees where the land is thereafter converted to a nonforest use. Examples of deforestation include conversion of forestland to farms, ranches, or urban use....
is the conversion of forested areas to non-forested areas. The main sources of deforestation in the Amazon are human settlement and development of the land. Prior to the early 1960s, access to the forest's interior was highly restricted, and the forest remained basically intact. Farms established during the 1960s were based on crop cultivation and the
slash and burnSlash-and-burn is an agricultural technique which involves cutting and burning of forests or woodlands to create fields. It is subsistence agriculture that typically uses little technology or other tools. It is typically part of shifting cultivation agriculture, and of transhumance livestock...
method. However, the colonists were unable to manage their fields and the crops because of the loss of soil fertility and
weedA weed in a general sense is a plant that is considered by the user of the term to be a nuisance, and normally applied to unwanted plants in human-controlled settings, especially farm fields and gardens, but also lawns, parks, woods, and other areas. More specifically, the term is often used to...
invasion. The soils in the Amazon are productive for just a short period of time, so farmers are constantly moving to new areas and clearing more land. These farming practices led to deforestation and caused extensive environmental damage. Deforestation is considerable, and areas cleared of forest are visible to the naked eye from outer space.
Between 1991 and 2000, the total area of forest lost in the Amazon rose from 415000 to 587000 km² (160,232.4 to 226,642 sqmi), with most of the lost forest becoming pasture for cattle. Seventy percent of formerly forested land in the Amazon, and 91% of land deforested since 1970, is used for livestock
pastureA ranch is an area of landscape, including various structures, given primarily to the practice of ranching, the practice of raising grazing livestock such as cattle or sheep for meat or wool. The word most often applies to livestock-raising operations in the western United States and Canada, though...
. In addition, Brazil is currently the second-largest global producer of
soybeanThe soybean or soya bean is a species of legume native to East Asia, widely grown for its edible bean which has numerous uses...
s after the United States. The needs of soy farmers have been used to validate many of the controversial transportation projects that are currently developing in the Amazon. The first two highways successfully opened up the rain forest and led to increased settlement and deforestation. The mean annual deforestation rate from 2000 to 2005 (22392 km² or 8,645.6 sq mi per year) was 18% higher than in the previous five years (19018 km² or 7,342.9 sq mi per year). Deforestation has declined significantly in the Brazilian Amazon since 2004.
Conservation and climate change
Environmentalists are concerned about loss of biodiversity that will result from destruction of the forest, and also about the release of the
carbonCarbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...
contained within the
vegetationVegetation is a general term for the plant life of a region; it refers to the ground cover provided by plants. It is a general term, without specific reference to particular taxa, life forms, structure, spatial extent, or any other specific botanical or geographic characteristics. It is broader...
, which could accelerate
global warmingGlobal warming refers to the rising average temperature of Earth's atmosphere and oceans and its projected continuation. In the last 100 years, Earth's average surface temperature increased by about with about two thirds of the increase occurring over just the last three decades...
. Amazonian evergreen forests account for about 10% of the world's terrestrial primary productivity and 10% of the carbon stores in ecosystems—of the order of 1.1 × 10
11 metric tonnes of carbon. Amazonian forests are estimated to have accumulated 0.62 ± 0.37 tons of carbon per hectare per year between 1975 and 1996.
One
computer modelA General Circulation Model is a mathematical model of the general circulation of a planetary atmosphere or ocean and based on the Navier–Stokes equations on a rotating sphere with thermodynamic terms for various energy sources . These equations are the basis for complex computer programs commonly...
of future
climate changeClimate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...
caused by
greenhouse gasA greenhouse gas is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range. This process is the fundamental cause of the greenhouse effect. The primary greenhouse gases in the Earth's atmosphere are water vapor, carbon dioxide, methane, nitrous oxide, and ozone...
emissions shows that the Amazon rainforest could become unsustainable under conditions of severely reduced rainfall and increased temperatures, leading to an almost complete loss of rainforest cover in the basin by 2100. However, simulations of Amazon basin climate change across many different models are not consistent in their estimation of any rainfall response, ranging from weak increases to strong decreases. The result indicates that the rainforest could be threatened though the 21st century by climate change in addition to deforestation.
In 1989, environmentalist C.M. Peters and two colleagues stated there is economic as well as biological incentive to protecting the rainforest. One hectare in the
Peruvian AmazonThe Peruvian Amazon is the area of the Amazon jungle included in the territory of Peru, from the east of the Andes to borders with Ecuador, Colombia, Brazil and Bolivia. This region comprises 60% of the country and is marked by a large degree of biodiversity...
has been calculated to have a value of $6820 if intact forest is sustainably harvested for fruits, latex, and timber; $1000 if clear-cut for commercial timber (not sustainably harvested); or $148 if used as cattle pasture.
As indigenous territories continue to be destroyed by deforestation and
ecocideThe neologism ecocide can be used to refer to any large-scale destruction of the natural environment or over-consumption of critical non-renewable resources...
, such as in the
Peruvian AmazonThe Peruvian Amazon is the area of the Amazon jungle included in the territory of Peru, from the east of the Andes to borders with Ecuador, Colombia, Brazil and Bolivia. This region comprises 60% of the country and is marked by a large degree of biodiversity...
indigenous peoplesIndigenous peoples are ethnic groups that are defined as indigenous according to one of the various definitions of the term, there is no universally accepted definition but most of which carry connotations of being the "original inhabitants" of a territory....
' rainforest communities continue to disappear, while others, like the
UrarinaThe Urarina are an indigenous people of the Peruvian Amazon Basin who inhabit the Chambira, Urituyacu, and Corrientes Rivers. According to both archaeological and historical sources, they have resided in the Chambira Basin of contemporary northeastern Peru for centuries. The Urarina refer to...
continue to struggle to fight for their cultural survival and the fate of their forested territories. Meanwhile, the relationship between non-human primates in the subsistence and symbolism of indigenous lowland South American peoples has gained increased attention, as has ethno-biology and
community-based conservationCommunity-based conservation is a res conservation movements that emerged in the 1980s through escalating protests and subsequent dialogue with local communities affected by international attempts to protect the biodiversity of the earth. Older conservation movements disregarded the interests of...
efforts.
From 2002 to 2006, the conserved land in the Amazon rainforest has almost tripled and deforestation rates have dropped up to 60%. About 1000000 square kilometres (247,105,163 acre) have been put onto some sort of conservation, which adds up to a current amount of 1730000 square kilometres (427,491,932 acre).
A 2009 study found that a 4 °C rise in global temperatures by 2100 would kill 85% of the Amazon rainforest while a temperature rise of 3 °C would kill some 75% of the Amazon.
Remote sensing
The use of
remotely sensedRemote sensing is the acquisition of information about an object or phenomenon, without making physical contact with the object. In modern usage, the term generally refers to the use of aerial sensor technologies to detect and classify objects on Earth by means of propagated signals Remote sensing...
data is dramatically improving conservationists' knowledge of the Amazon Basin. Given the objectivity and lowered costs of satellite-based land cover analysis, it appears likely that remote sensing technology will be an integral part of assessing the extent and damage of deforestation in the basin. Furthermore, remote sensing is the best and perhaps only possible way to study the Amazon on a large-scale.
The use of remote sensing for the conservation of the Amazon is also being used by the indigenous tribes of the basin to protect their tribal lands from commercial interests. Using handheld
GPSThe Global Positioning System is a space-based global navigation satellite system that provides location and time information in all weather, anywhere on or near the Earth, where there is an unobstructed line of sight to four or more GPS satellites...
devices and programs like
Google EarthGoogle Earth is a virtual globe, map and geographical information program that was originally called EarthViewer 3D, and was created by Keyhole, Inc, a Central Intelligence Agency funded company acquired by Google in 2004 . It maps the Earth by the superimposition of images obtained from satellite...
, members of the Trio Tribe, who live in the rainforests of southern Suriname, map out their ancestral lands to help strengthen their territorial claims. Currently, most tribes in the Amazon do not have clearly defined boundaries, making it easier for commercial ventures to target their territories.
To accurately map the Amazon's biomass and subsequent carbon related emissions, the classification of tree growth stages within different parts of the forest is crucial. In 2006 Tatiana Kuplich organized the trees of the Amazon into four categories: (1) mature forest, (2) regenerating forest [less than three years], (3) regenerating forest [between three and five years of regrowth], and (4) regenerating forest [eleven to eighteen years of continued development]. The researcher used a combination of
Synthetic aperture radarSynthetic-aperture radar is a form of radar whose defining characteristic is its use of relative motion between an antenna and its target region to provide distinctive long-term coherent-signal variations that are exploited to obtain finer spatial resolution than is possible with conventional...
(SAR) and
Thematic MapperOne of the Earth observing sensors introduced in the Landsat program. A Thematic Mapper was first placed aboard Landsat 4 , and one is still operational aboard Landsat 5. TM sensors feature seven bands of image data most of which have 30 metre spatial resolution...
(TM) to accurately place the different portions of the Amazon into one of the four classifications.
Impact of early 21st century Amazon droughts
In 2005, parts of the Amazon basin experienced the worst drought in one hundred years, and there were indications that 2006 could have been a second successive year of drought. A July 23, 2006 article in the UK newspaper
The IndependentThe Independent is a British national morning newspaper published in London by Independent Print Limited, owned by Alexander Lebedev since 2010. It is nicknamed the Indy, while the Sunday edition, The Independent on Sunday, is the Sindy. Launched in 1986, it is one of the youngest UK national daily...
reported
Woods Hole Research CenterThe Woods Hole Research Center addresses pressing environmental issues, including climate change, through scientific and policy initiatives. The Center has projects in the Amazon, the Arctic, Africa, Russia, Alaska, Canada, New England, and the Mid-Atlantic, working in collaboration with a wide...
results showing that the forest in its present form could survive only three years of drought. Scientists at the Brazilian
National Institute of Amazonian ResearchThe National Institute of Amazonian Research is a public educational and research institution in Manaus, Brazil. It was founded in 1952, with the purpose of providing a further knowledge about the Brazilian Amazon Region...
argue in the article that this drought response, coupled with the effects of deforestation on regional climate, are pushing the rainforest towards a "
tipping pointA climate tipping point is a point when global climate changes from one stable state to another stable state, in a similar manner to a wine glass tipping over. After the tipping point has been passed, a transition to a new state occurs...
" where it would irreversibly start to die. It concludes that the forest is on the brink of being turned into
savannaA savanna, or savannah, is a grassland ecosystem characterized by the trees being sufficiently small or widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of C4 grasses.Some...
or
desertA desert is a landscape or region that receives an extremely low amount of precipitation, less than enough to support growth of most plants. Most deserts have an average annual precipitation of less than...
, with catastrophic consequences for the world's climate.
According to the
World Wide Fund for NatureThe World Wide Fund for Nature is an international non-governmental organization working on issues regarding the conservation, research and restoration of the environment, formerly named the World Wildlife Fund, which remains its official name in Canada and the United States...
, the combination of climate change and deforestation increases the drying effect of dead trees that fuels forest fires.
In 2010 the Amazon rainforest experienced another severe drought, in some ways more extreme than the 2005 drought. The affected region was approximate 1160000 square miles (3,004,386.2 km²) of rainforest, compared to 734000 square miles (1,901,051.3 km²) in 2005. The 2010 drought had three epicenters where vegetation died off, whereas in 2005 the drought was focused on the southwestern part. The findings were published in the journal Science. In a typical year the Amazon absorbs 1.5 gigatons of carbon dioxide; during 2005 instead 5 gigatons were released and in 2010 8 gigatons were released
See also
- Peruvian Amazon
The Peruvian Amazon is the area of the Amazon jungle included in the territory of Peru, from the east of the Andes to borders with Ecuador, Colombia, Brazil and Bolivia. This region comprises 60% of the country and is marked by a large degree of biodiversity...
- Amanyé
The Amanayé are a Native South American nation of Brazil's Amazonia. Sedentary farmers, hunters and gatherers, they speak Tupí. They frequently relocate villages as their soil becomes exhausted, and possibly also to avoid their enemies. The Amanyé were first contacted in 1755, they tended to avoid...
- Amazon Conservation Team
The Amazon Conservation Team is a non-profit organization that works in partnership with indigenous people of tropical America in conserving the biodiversity of the Amazon Rainforest as well as the culture and land of its indigenous people....
(ACT)
- Amazonian Manatee
The Amazonian Manatee is a species of manatee that lives in the freshwater habitats of the Amazon basin. They are found in Brazil, Peru, Colombia, Ecuador, Guyana and Venezuela. Amazonian manatees are aquatic animals of the Sirenia order and are also known as "seacows". Their colour is grey but...
- Amazon Watch
Founded in 1996, Amazon Watch is a nonprofit organization based in San Francisco, California. It works to protect the rainforest and advance the rights of indigenous peoples in the Amazon Basin...
- Atlantic Forest
- Coordinator of Indigenous Organizations of the Amazon River Basin
Coordinator of Indigenous Organizations of the Amazon River Basin was founded in 1984 in Lima, Peru. This organization coordinates the following nine national Amazonian indigenous organizations:...
(COICA)
- Iquitos
Iquitos is the largest city in the Peruvian rainforest, with a population of 370,962. It is the capital of Loreto Region and Maynas Province.Located on the Amazon River, it is only above sea level, although it is more than from the mouth of the Amazon at Belém on the Atlantic Ocean...
- Rainforest Action Network
Rainforest Action Network is an environmental organization based in San Francisco, California, USA. The organization was founded by Randy "Hurricane" Hayes and Mike Roselle in 1985, with the financial help of Fund for Wild Nature....
- Rainforest Foundation Fund
- List of plants of Amazon Rainforest vegetation of Brazil
- Amazon Surveillance System (Sistema de Vigilância da Amazônia)
- Bandeirantes
The bandeirantes were composed of Indians , caboclos , and some whites who were the captains of the Bandeiras. Members of the 16th–18th century South American slave-hunting expeditions called bandeiras...
- Save the Amazon Rainforest Organisation
Save the Amazon Rainforest Organisation is a charity that aims to save the Amazon rainforest from destruction, and is based in London in the United Kingdom.-Introduction:...
(STARO)
- Tapiche Ohara's Reserve
The 1,540 hectare Reserve, accessible only by waterway, is located 340 km up river from Iquitos on the Tapiche River. The Reserve comprises several types of lowland Amazonian forests, including igapo, varzea, and terra firme...
Further reading
- "Deforestation." World Geography. Columbus, Ohio: McGraw-Hill/Glencoe, 2000. 202–204
External links