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Forest cover

From Wikipedia, the free encyclopedia
Amount of land area covered by forest

Forest cover is the amount oftrees that covers a particular area of land. It may be measured as relative (inpercent) or absolute (insquare kilometres/square miles). Nearly a third of the world's land surface is covered with forest, with closed-canopy forest accounting for 4 - 5 billion hectares of land.[1] Forests provide manyecosystem services that humans and animals cannot survive without, but anthropogenic actions and climate change are threatening global forest cover in potentially irreversible ways.

Global patterns

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Forest cover by the numbers

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According to the FAO's Global Forest Resources Assessment 2020, the world has a totalforest area of 4.06 billion hectares (10.0 billion acres), which is 31% of the total land area. More than one-third of the world's forest cover is primary forest: naturally regenerated forests with native species and no visible indication of human activity.[2]

More than half (54%) of the world's forests are found in only five countries (Brazil,Canada,China,Russia and the United States). Countries with the highest share of forest area in land area are located in all regions of the world, mostly the tropical ones; they also tend to be low- and middle-income countries. In 2022, forest covered 95% of the land area inSuriname, 94% inGuyana and 92% in theFederated States of Micronesia.[3] Russia has the largest forest area in the world, at 815 million hectares (a fifth of global forest cover). The other four countries all house more than 100 million hectares of forest each. The small African nation ofGabon, while only containing 0.58% of the world's forest cover, has the largest forest-to-land ratio of any country (91.3%).[4]

Variation in forest ecosystems

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Forests are found throughout the world on a spatial scale determined by temperature and precipitation. There are four types of forest biomes:tropical,temperate, subtropical, andboreal. Most of the world's forest cover (45%) is found in the tropics, which is defined by high temperature and humidity. The boreal zone, which includes Russia and theArctic, contains the second largest amount of forest (33%). The temperate/subtropical zone, located between the tropical and the boreal, contains 25%. Almost half of global forest cover (49%) is relatively continuous, while 9% is found in fragments with little to no connectivity. Roughly 80% of the world's forest area is found in patches larger than 1 million hectares (2.5 million acres). The remaining 20% is located in more than 34 million patches across the world[5] with the vast majority being less than 1,000 hectares (2,500 acres) in size.Tropical rainforests and borealconiferous forests are the least fragmented, whereassubtropical dry forest and temperate oceanic forests are among the most fragmented.

Ecological impacts

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Benefits of forest cover

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The World Health Organization has compiled a list ofecological goods and services that depend on forests and without which humans could not survive, including: flood and drought mitigation, water purification, erosion control, and disease reduction.[6] Tropical forests especially act as one of the world's largestcarbon sinks, accumulating atmospheric carbon dioxide during photosynthesis and thus mitigating climate change. Maintaining the size, continuity, and biodiversity of the world's forests is crucial for human health and prosperity. However, forest cover is severely threatened bydeforestation, as a direct consequence ofagriculture,grazing,[7] andmining.[8] Since the onset of agriculture (about 12,000 years ago), the number of trees worldwide has dropped by 46%.[9] Since 1990, the world has lost 178 million ha of forest (an area roughly the size of Libya).

Forest cover remediation tactics

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Although global forest area is decreasing, the rate at which we are losing trees has slowed. In the 1990s the world was losing 7.8 million ha of area per year, but in the 2000s this rate slowed to 5.2 million ha, and in the 2010s it shrank even further (down to 4.7 million). This pattern is due to the regeneration abilities of forests, as well as a conscious global effort to reduce deforestation. Plantation forests are one method ofreforestation/afforestation that has become increasingly popular since the 1990s. Intensively planned to be biodiverse and well-managed, these forests exist for the purpose of regenerating our global forest cover.[10] Although it is impossible to gain back the ecosystem services lost when a plot of forest is destroyed for industrial purposes, these new regenerative methods carry hope for the future of our global forest biome.[citation needed]

See also

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Sources

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 This article incorporates text from afree content work. Licensed under CC BY-SA 3.0 (license statement/permission). Text taken fromGlobal Forest Resources Assessment 2020 Key findings​, FAO, FAO.

 This article incorporates text from afree content work. Licensed under CC BY-SA 3.0 (license statement/permission). Text taken fromThe State of the World's Forests 2020. In brief – Forests, biodiversity and people​, FAO & UNEP, FAO & UNEP.

References

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  1. ^Freedman, Bill (1995). "Harvesting of Forests".Environmental Ecology. pp. 278–337.doi:10.1016/B978-0-08-050577-0.50014-5.ISBN 978-0-12-266542-4.A closed-canopy forest covers about 4–5 billion ha
  2. ^Global Forest Resources Assessment 2020 – Terms and definitions(PDF). Rome: FAO. 2018.
  3. ^World Food and Agriculture – Statistical Yearbook 2024. 2024.doi:10.4060/cd2971en.ISBN 978-92-5-139255-3.[page needed]
  4. ^Ritchie, Hannah;Roser, Max (2021-02-09)."Forests and Deforestation".Our World in Data.
  5. ^The State of the World's Forests 2020. In brief. 2020. pp. 7–9.doi:10.4060/ca8985en.ISBN 978-92-5-132707-4.
  6. ^Karjalainen, Eeva; Sarjala, Tytti; Raitio, Hannu (January 2010)."Promoting human health through forests: overview and major challenges".Environmental Health and Preventive Medicine.15 (1):1–8.Bibcode:2010EHPM...15....1K.doi:10.1007/s12199-008-0069-2.PMC 2793342.PMID 19568838.
  7. ^State of the World's Forests 2016. Rome: FAO. 2016.ISBN 978-92-5-109208-8.
  8. ^Weisse, Mikaela; Goldman, Elizabeth Dow (2017-10-23)."Global Tree Cover Loss Rose 51 Percent in 2016".World Resources Institute. Retrieved2018-02-16.
  9. ^Ehrenberg, Rachel (2 September 2015). "Global forest survey finds trillions of trees".Nature.doi:10.1038/nature.2015.18287.
  10. ^Global Forest Resources Assessment 2020. 2020. pp. 2–6.doi:10.4060/ca8753en.ISBN 978-92-5-132581-0.

External links

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Africa
Deforestation in Brazil
Americas
Asia
Europe
Oceania
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Forestry by country
Africa
Americas
Asia
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