Amazon Forest

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Amazon Forest :

Amazon Forest The Amazon Forest (in Portuguese , Floresta Amazônica or Amazônia ; Spanish Selva Amazónica , Amazonía or usually Amazonia ), also known in English as Amazonia or the Amazon Jungle, is a moist broadleaf forest that covers most of the Amazon Basin 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 forest. This region includes territory belonging to nine nations. The majority of the forest is contained within Brazil , with 60% of the forest, followed by Peru with 13%, Colombian Amazon with 10%, and with minor amounts in, Venezuela, Ecuador, Bolivia, Guyana, Suriname and France ( French Guiana ). States or departments in four nations bear the name Amazonas after it. The Amazon represents over half of the planet's remaining forests , and it comprises the largest and most species-rich tract of tropical forest in the world.



Biodiversity :

Biodiversity Wet tropical forests are the most species-rich biome , and tropical forests in the Americas are consistently more species rich than the wet forests in Africa and Asia. [17] As the largest tract of tropical rainforest in the Americas, the Amazonian rainforests have unparalleled biodiversity . One in ten known species in the world lives in the Amazon Rainforest. [18] This constitutes the largest collection of living plants and animal species in the world. The region is home to about 2.5 million insect species , [19] tens of thousands of plants, and some 2,000 birds and mammals . To date, at least 40,000 plant species, 2,200 fishes [20] , 1,294 birds, 427 mammals, 428 amphibians, and 378 reptiles have been scientifically classified in the region. [21] 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 invertebrate species in Brazil alone. [22] The biodiversity 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. [23]

Deforestation :

Deforestation Main article: Deforestation of the Amazon Rainforest Deforestation 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. [29] Prior to the early 1960s, access to the forest's interior was highly restricted, and the forest remained basically intact. [30] Farms established during the 1960s were based on crop cultivation and the slash and burn method. However, the colonists were unable to manage their fields and the crops because of the loss of soil fertility and weed invasion. [31] 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. [31] These farming practices led to deforestation and caused extensive environmental damage. [32] 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 415,000 to 587,000 square kilometres (160,000 to 227,000 sq mi), with most of the lost forest becoming pasture for cattle. [33] Seventy percent of formerly forested land in the Amazon, and 91% of land deforested since 1970, is used for livestock pasture . [34] [35] In addition, Brazil is currently the second-largest global producer of soybeans 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 (22,392 km2 or 8,646 sq mi per year) was 18% higher than in the previous five years (19,018 km2 or 7,343 sq mi per year). [36] Deforestation has declined significantly in the Brazilian Amazon since 2004. [37]

Conservation and climate change :

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 carbon contained within the vegetation , which could accelerate global warming . Amazonian evergreen forests account for about 10% of the world's terrestrial primary productivity and 10% of the carbon stores in ecosystems [38] —of the order of 1.1 × 1011 metric tonnes of carbon. [39] Amazonian forests are estimated to have accumulated 0.62 ± 0.37 tons of carbon per hectare per year between 1975 and 1996. [39] One computer model of future climate change caused by greenhouse gas 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. [40] [41] 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. [42] The result indicates that the rainforest could be threatened though the 21st century by climate change in addition to deforestation.

Remote sensing :

Remote sensing The use of remotely sensed 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. [47] Furthermore, remote sensing is the best and perhaps only possible way to study the Amazon on a large-scale. [48] 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 GPS devices and programs like Google Earth , members of the Trio Tribe, who live in the rainforests of southern Suriname, map out their ancestral lands to help strengthen their territorial claims. [49] Currently, most tribes in the Amazon do not have clearly defined boundaries, making it easier for commercial ventures to target their territories.



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