Forest: Difference between revisions

Forests form distinctly different [[biome]]s at different latitudes and elevations, and with different precipitation and [[evapotranspiration]] rates. <ref>{{Cite book|last=Holdridge |first=L.R. |url=http://reddcr.go.cr/sites/default/files/centro-de-documentacion/holdridge_1966_-_life_zone_ecology.pdf |archive-url=https://web.archive.org/web/20161005035018/http://reddcr.go.cr/sites/default/files/centro-de-documentacion/holdridge_1966_-_life_zone_ecology.pdf |archive-date=5 October 2016 |url-status=live |title=Life zone ecology |publisher=Tropical Science Center |location=San Jose, Costa Rica}}</ref> These biomes include [[boreal]] forests in subarctic climates, [[tropical and subtropical moist broadleaf forests|tropical moist forests]] and [[tropical and subtropical dry broadleaf forests|tropical dry forests]] around the [[tropics|Equator]], and [[temperate forest]]s at the [[middle latitudes]]. Forests form in areas of the Earth with high rainfall, while drier conditions produce a transition to [[savanna]]. However, in areas with intermediate rainfall levels, forest transitions to savanna rapidly when the percentage of land that is covered by trees drops below 40 to 45 percent.<ref>{{cite web |last1=Edwards |first1=Lin |title=Forest and savanna can switch quickly |url=https://phys.org/news/2011-10-forest-savanna-quickly.html |website=Phys.org}}</ref> Research conducted in the [[Amazon rainforest]] shows that trees can alter rainfall rates across a region, releasing water from their leaves in anticipation of seasonal rains to trigger the wet season early. Because of this, seasonal rainfall in the Amazon begins 2 to 3 months earlier than the climate would otherwise allow.<ref>{{cite web |last1=Rasmussen |first1=Carol |title=New study shows the Amazon makes its own rainy season |url=https://climate.nasa.gov/news/2608/new-study-shows-the-amazon-makes-its-own-rainy-season/ |website=nasa.gov}}</ref><ref>{{cite web |last1=Loomis |first1=Ilima |title=Trees in the Amazon make their own rain |url=https://www.science.org/content/article/trees-amazon-make-their-own-rain}}</ref> [[Deforestation]] in the Amazon and anthropogenic [[climate change]] hold the potential to interfere with this process, causing the forest to pass a threshold where it transitions into savanna.<ref>{{cite web |last1=Kimbrough |first1=Liz |title=More droughts are coming, and the Amazon can't keep up: Study |url=https://news.mongabay.com/2022/09/more-droughts-are-coming-and-the-amazon-isnt-ready-study/ |website=Mongabay|date=16 September 2022 }}</ref>

[[Deforestation]] threatens many forest ecosystems. Deforestation occurs when humans remove trees from a forested area by cutting or burning, either to harvest [[timber]] or to make way for farming. Most deforestation today occurs in tropical forests. The vast majority of this deforestation is because of the production of four commodities: [[wood]], [[beef]], [[soy]], and [[palm oil]].<ref>{{cite web |last1=Derouin |first1=Sarah |title=Deforestation: facts, causes & effects |url=https://www.livescience.com/27692-deforestation.html |website=Live Science|date=6 January 2022 }}</ref> Over the past 2,000 years, the area of land covered by forest in [[Europe]] has been reduced from 80% to 34%. Large areas of forest have also been cleared in [[China]] and in the eastern [[United States]],<ref>{{cite web |title=Deforestation |url=https://education.nationalgeographic.org/resource/deforestation/ |publisher=National Geographic}}</ref> in which only 0.1% of land was left undisturbed.<ref>{{cite web |title=Eastern Deciduous Forest (U.S. National Park Service) |url=https://www.nps.gov/im/ncrn/eastern-deciduous-forest.htm |website=nps.gov}}</ref> Almost half of Earth's forest area (49 percent) is relatively intact, while 9 percent is found in fragments with little or no connectivity. Tropical rainforests and boreal coniferous forests are the least fragmented, whereas subtropical dry forests and temperate oceanic forests are among the most fragmented. Roughly 80 percent of the world's forest area is found in patches larger than {{convert|1|e6ha|abbr=off}}. The remaining 20 percent is located in more than 34 million patches around the world – the vast majority less than {{convert|1000|ha}} in size.<ref name="auto"/>

The term forest-dependent people is used to describe any of a wide variety of livelihoods that are dependent on access to forests, products harvested from forests, or ecosystem services provided by forests, including those of Indigenous peoples dependent on forests.<ref name="auto1">{{cite journal |last1=Newton |first1=Peter |last2=Miller |first2=Daniel C. |last3=Byenkya |first3=Mugabi Augustine Ateenyi |last4=Agrawal |first4=Arun |title=Who are forest-dependent people? A taxo nomy to aid livelihood and land use decision-making in forested regions |journal=Land Use Policy |date=2016 |volume=57 |pages=388–395|doi=10.1016/j.landusepol.2016.05.032 }}</ref> In [[India]], approximately 22 percent of the population belongs to forest-dependent communities, which live in close proximity to forests and practice [[agroforestry]] as a principal part of their livelihood.<ref>{{cite web |last1=Prateek |first1=Gautam |last2=Punia |first2=Sumendera |title=India's forest-dependent communities will benefit from policies recognising their integrated agri-forestry livelihood |url=https://www.downtoearth.org.in/blog/forests/india-s-forest-dependent-communities-will-benefit-from-policies-recognising-their-integrated-agri-forestry-livelihood-86929 |website=DownToEarth}}</ref> People of [[Ghana]] who rely on [[timber]] and [[bushmeat]] harvested from forests and Indigenous peoples of the Amazon rainforest are also examples of forest-dependent people.<ref name="auto1"/> Though forest-dependence by more common definitions is statistically associated with poverty and [[rural]] livelihoods, elements of forest-dependence exist in communities with a wide range of characteristics. Generally, richer households derive more cash value from forest resources, whereas among poorer households, forest resources are more important for home consumption and increase community resilience.<ref>{{Cite web|url=https://www.iucn.org/news/forests/201611/understanding-human-dependence-forests-overview-iucn%E2%80%99s-efforts-and-findings-and-their-implications|title=Understanding human dependence on forests: An overview of IUCN’sIUCN's efforts and findings, and their implications|date=2 November 2016|website=IUCN}}</ref>