Editing Tropical rainforest (section)

{{Short description|Tropical broadleaf forest with high rainfall}}
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[[File:Aerial view of the Amazon Rainforest.jpg|thumb|upright=1.3|An area of the [[Amazon rainforest]] in [[Brazil]]. The tropical rainforests of [[South America]] contain the largest [[biodiversity|diversity]] of species on [[Earth]].<ref>[http://earthobservatory.nasa.gov/Newsroom/view.php?id=28907 Why the Amazon Rainforest is So Rich in Species] {{webarchive|url=https://web.archive.org/web/20110225204348/http://earthobservatory.nasa.gov/Newsroom/view.php?id=28907 |date=25 February 2011 }}. Earthobservatory.nasa.gov (5 December 2005). Retrieved on 28 March 2013.</ref><ref>[https://www.sciencedaily.com/releases/2005/12/051205163236.htm Why The Amazon Rainforest Is So Rich In Species]. ScienceDaily.com (5 December 2005). Retrieved on 28 March 2013.</ref>]]
[[File:Koppen-Geiger Map Af present.svg|thumb|upright=1.3|Tropical rainforest climate zones (Af).]]
[[File:Tropical_Forests_2000_by_Major_Ecological_Domains.tif|thumb|300px|right|Tropical forests: from the UN FRA2000 report]]

'''Tropical rainforests''' are dense and warm [[rainforest]]s with high rainfall typically found between 10° north and south of the [[Equator]]. They are a subset of the [[tropical forest]] [[biome]] that occurs roughly within the 28° latitudes (in the [[torrid zone]] between the [[Tropic of Cancer]] and [[Tropic of Capricorn]]). Tropical rainforests are a type of [[tropical moist broadleaf forest]], that includes the more extensive [[seasonal tropical forest]]s.<ref name=Olson/> True rainforests usually occur in [[tropical rainforest climate]]s where no [[dry season]] occurs; all months have an average [[precipitation]] of at least {{cvt|60|mm|in}}. Seasonal tropical forests with [[tropical monsoon climate|tropical monsoon]] or [[tropical savanna climate|savanna]] climates are sometimes included in the broader definition.

Tropical rainforests ecosystems are distinguished by their consistent, high temperatures, exceeding {{cvt|18|C|F}} monthly, and substantial annual rainfall. The abundant rainfall results in nutrient-poor, leached soils, which profoundly affect the flora and fauna adapted to these conditions. These rainforests are renowned for their significant [[biodiversity]]. They are home to 40–75% of all species globally, including half of the world's animal and plant species, and two-thirds of all flowering plant species. Their dense [[insect]] population and variety of trees and higher plants are notable. Described as the "world's largest pharmacy", over a quarter of natural medicines have been discovered in them. However, tropical rainforests are threatened by human activities, such as [[logging]] and agricultural expansion, leading to [[habitat fragmentation]] and [[habitat destruction|loss]].

The structure of a tropical rainforest is stratified into layers, each hosting unique [[ecosystem]]s. These include the emergent layer with towering trees, the densely populated [[canopy (biology)|canopy]] layer, the [[understory]] layer rich in wildlife, and the [[forest floor]], which is sparse due to low light penetration. The soil is characteristically nutrient-poor and acidic. Tropical rainforests have a long history of [[ecological succession]], influenced by natural events and human activities. They are crucial for global ecological functions, including [[carbon sequestration]] and [[climate]] regulation. Many [[indigenous peoples]] around the world have inhabited rainforests for millennia, relying on them for sustenance and shelter, but face challenges from modern economic activities.

[[nature conservation|Conservation]] efforts are diverse, focusing on both preservation and sustainable management. International policies, such as the Reducing Emissions from Deforestation and Forest Degradation ([[REDD and REDD+]]) programs, aim to curb [[deforestation]] and forest degradation. Despite these efforts, tropical rainforests continue to face significant threats from deforestation and [[climate change]], highlighting the ongoing challenge of balancing conservation with human development needs.