Industrial era




In the 19th century, introduction of steamboats in the United States was the cause of deforestation of banks of major rivers, such as the Mississippi River, with increased and more severe flooding one of the environmental results. The steamboat crews cut wood every day from the riverbanks to fuel the steam engines. Between St. Louis and the confluence with the Ohio River to the south, the Mississippi became more wide and shallow, and changed its channel laterally. Attempts to improve navigation by the use of snag pullers often resulted in crews' clearing large trees 100 to 200 feet (61 m) back from the banks. Several French colonial towns of the Illinois Country, such as Kaskaskia, Cahokia and St. Philippe, Illinois, were flooded and abandoned in the late 19th century, with a loss to the cultural record of their archeology.

The wholescale clearance of woodland to create agricultural land can be seen in many parts of the world, such as the Central forest-grasslands transition and other areas of the Great Plains of the United States. Specific parallels are seen in the 20th-century deforestation occurring in many developing nations.

Rates of deforestation

Estimates vary widely as to the extent of tropical deforestation.

Present-day

In 2019, the world lost nearly 12 million hectares of tree cover. Nearly a third of that loss, 3.8 million hectares, occurred within humid tropical primary forests, areas of mature rainforest that are especially important for biodiversity and carbon storage. That’s the equivalent of losing an area of primary forest the size of a football pitch every six seconds.

History

Global deforestation sharply accelerated around 1852. As of 1947, the planet had 15 million to 16 million km2 (5.8 million to 6.2 million sq mi) of mature tropical forests, but by 2015, it was estimated that about half of these had been destroyed. Total land coverage by tropical rainforests decreased from 14% to 6%. Much of this loss happened between 1960 and 1990, when 20% of all tropical rainforests were destroyed. At this rate, extinction of such forests is projected to occur by the mid-21st century.

In the early 2000s, some scientists predicted that unless significant measures (such as seeking out and protecting old growth forests that have not been disturbed) are taken on a worldwide basis, by 2030 there will only be 10% remaining, with another 10% in a degraded condition. 80% will have been lost, and with them hundreds of thousands of irreplaceable species.

Rates of change

A 2002 analysis of satellite imagery suggested that the rate of deforestation in the humid tropics (approximately 5.8 million hectares per year) was roughly 23% lower than the most commonly quoted rates. A 2005 report by the United Nations Food and Agriculture Organization (FAO) estimated that although the Earth's total forest area continued to decrease at about 13 million hectares per year, the global rate of deforestation had been slowing. On the other hand, a 2005 analysis of satellite images reveals that deforestation of the Amazon rainforest is twice as fast as scientists previously estimated.

From 2010 to 2015, worldwide forest area decreased by 3.3 million ha per year, according to FAO. During this five-year period, the biggest forest area loss occurred in the tropics, particularly in South America and Africa. Per capita forest area decline was also greatest in the tropics and subtropics but is occurring in every climatic domain (except in the temperate) as populations increase.

An estimated 420 million ha of forest has been lost worldwide through deforestation since 1990, but the rate of forest loss has declined substantially. In the most recent five-year period (2015–2020), the annual rate of deforestation was estimated at 10 million ha, down from 12 million ha in 2010–2015.

Africa had the largest annual rate of net forest loss in 2010–2020, at 3.9 million ha, followed by South America, at 2.6 million ha. The rate of net forest loss has increased in Africa in each of the three decades since 1990. It has declined substantially in South America, however, to about half the rate in 2010–2020 compared with 2000–2010. Asia had the highest net gain of forest area in 2010–2020, followed by Oceania and Europe. Nevertheless, both Europe and Asia recorded substantially lower rates of net gain in 2010–2020 than in 2000–2010. Oceania experienced net losses of forest area in the decades 1990–2000 and 2000–2010.

Some claim that rainforests are being destroyed at an ever-quickening pace. The London-based Rainforest Foundation notes that "the UN figure is based on a definition of forest as being an area with as little as 10% actual tree cover, which would therefore include areas that are actually savanna-like ecosystems and badly damaged forests". Other critics of the FAO data point out that they do not distinguish between forest types, and that they are based largely on reporting from forestry departments of individual countries, which do not take into account unofficial activities like illegal logging. Despite these uncertainties, there is agreement that destruction of rainforests remains a significant environmental problem.

Methods of analysis

Some have argued that deforestation trends may follow a Kuznets curve, which if true would nonetheless fail to eliminate the risk of irreversible loss of non-economic forest values (for example, the extinction of species).

Some cartographers have attempted to illustrate the sheer scale of deforestation by country using a cartogram.

Regions

Rates of deforestation vary around the world.

Up to 90% of West Africa's coastal rainforests have disappeared since 1900. Madagascar has lost 90% of its eastern rainforests.

In South Asia, about 88% of the rainforests have been lost.

Mexico, India, the Philippines, Indonesia, Thailand, Burma, Malaysia, Bangladesh, China, Sri Lanka, Laos, Nigeria, the Democratic Republic of the Congo, Liberia, Guinea, Ghana and the Ivory Coast, have lost large areas of their rainforest.

Much of what remains of the world's rainforests is in the Amazon basin, where the Amazon Rainforest covers approximately 4 million square kilometres. Some 80% of the deforestation of the Amazon can be attributed to cattle ranching, as Brazil is the largest exporter of beef in the world. The Amazon region has become one of the largest cattle ranching territories in the world. The regions with the highest tropical deforestation rate between 2000 and 2005 were Central America—which lost 1.3% of its forests each year—and tropical Asia. In Central America, two-thirds of lowland tropical forests have been turned into pasture since 1950 and 40% of all the rainforests have been lost in the last 40 years. Brazil has lost 90–95% of its Mata Atlântica forest. Deforestation in Brazil increased by 88% for the month of June 2019, as compared with the previous year. However, Brazil still destroyed 1.3 million hectares in 2019. Brazil is one of several countries that have declared their deforestation a national emergency. Paraguay was losing its natural semi humid forests in the country's western regions at a rate of 15.000 hectares at a randomly studied 2-month period in 2010, Paraguay's parliament refused in 2009 to pass a law that would have stopped cutting of natural forests altogether.

As of 2007, less than 50% of Haiti's forests remained.

The World Wildlife Fund's ecoregion project catalogues habitat types throughout the world, including habitat loss such as deforestation, showing for example that even in the rich forests of parts of Canada such as the Mid-Continental Canadian forests of the prairie provinces half of the forest cover has been lost or altered.

In 2011 Conservation International listed the top 10 most endangered forests, characterized by having all lost 90% or more of their original habitat, and each harboring at least 1500 endemic plant species (species found nowhere else in the world).

Top 10 Most Endangered Forests 2011
Endangered forest Region Remaining habitat Predominate vegetation type Notes
Indo-Burma Asia-Pacific 5% Tropical and subtropical moist broadleaf forests Rivers, floodplain wetlands, mangrove forests. Burma, Thailand, Laos, Vietnam, Cambodia, India.
New Caledonia Asia-Pacific 5% Tropical and subtropical moist broadleaf forests See note for region covered.
Sundaland Asia-Pacific 7% Tropical and subtropical moist broadleaf forests Western half of the Indo-Malayan archipelago including southern Borneo and Sumatra.
Philippines Asia-Pacific 7% Tropical and subtropical moist broadleaf forests Forests over the entire country including 7,100 islands.
Atlantic Forest South America 8% Tropical and subtropical moist broadleaf forests Forests along Brazil's Atlantic coast, extends to parts of Paraguay, Argentina and Uruguay.
Mountains of Southwest China Asia-Pacific 8% Temperate coniferous forest See note for region covered.
California Floristic Province North America 10% Tropical and subtropical dry broadleaf forests See note for region covered.
Coastal Forests of Eastern Africa Africa 10% Tropical and subtropical moist broadleaf forests Mozambique, Tanzania, Kenya, Somalia.
Madagascar & Indian Ocean Islands Africa 10% Tropical and subtropical moist broadleaf forests Madagascar, Mauritius, Reunion, Seychelles, Comoros.
Eastern Afromontane Africa 11% Tropical and subtropical moist broadleaf forests
Montane grasslands and shrublands
Forests scattered along the eastern edge of Africa, from Saudi Arabia in the north to Zimbabwe in the south.
Table source:

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