RAINFOREST: FLORA, FAUNA, CHARACTERISTICS, CLIMATE, RELIEF - BIOLOGY - 2025

The tropical forest is a plant formation dominated by the tree biotype with a complex structure that develops in the intertropical zone. It is characterized by presenting several strata of vegetation and is one of the biomes with the greatest biological diversity on the planet.

There are basically four types of tropical forests which are the warm rain forest, the montane forest, the semi-deciduous forest and the deciduous forest. These forests extend in the intertropical strip (between the Tropics of Cancer and Capricorn) in America, Africa, Asia and Oceania.

Rainforest in the Amazon (Manaus, Brazil). Source: Neil Palmer / CIAT

This type of jungle is very exuberant, with high relative humidity and 3 to 4 layers of vegetation and is also known as cloudy forests.

The understory is made up of grasses and shrubs and reaches great development on the slopes most exposed to sunlight. In flat areas where the upper canopy is more closed and not much side light enters, the understory is more open.

Semi-deciduous rainforest

They are tropical rainforests in a bi-seasonal climate with 3 to 4 strata of vegetation and a dense understory. They can have a sufficient supply of water at the water table (groundwater).

In this ecosystem, some plant species maintain the foliage because they can obtain water from the water table thanks to a deep root system.

Another group of trees shed all their foliage in the dry season and thus reduce water loss. Therefore, in the dry season between 40 and 50% of the trees lose their foliage and in the rainy season they replace it.

Deciduous rainforest

They are dry tropical forests with a marked bi-seasonal climate and relatively low rainfall (900 to 1,500 mm per year). They can occur in areas with higher rainfall, but with limited water retention, due to the slope of the terrain or permeability of the soil.

In this type of forest, 80% or more of the species lose all their foliage in the dry season. The structure is relatively simple, with 2 or 3 strata, an open upper canopy, a dense understory, and less climbing and epiphytism.

- Role in planetary balance

Carbon sinks

Rainforests are the most productive terrestrial ecosystems on the planet and their capacity to accumulate biomass makes them an important carbon sink. Therefore, every tree in the jungle is incorporating atmospheric CO2 and fixing carbon as plant tissues.

This contributes to regulate atmospheric CO2 and reduce global warming, which today is one of the greatest environmental threats.

Oxygen production

Rainforests are not lungs (they do not consume oxygen, nor release CO2), they fulfill the opposite function. Rainforests consume CO2 and release O2 into the environment, but they also consume oxygen when they breathe.

These ecosystems are one of the main sources of O2, surpassed by marine phytoplankton.

Water cycle

Rainforests are huge masses of plants that transpire, taking water from the ground, filtering it and expelling it into the environment as vapor. On the other hand, the jungle works as a great protector of the soil, slows down the runoff of the water and facilitates infiltration.

Location

The tropical forests are located between the Tropic of Cancer (23º 26 ′ 14 ″ north latitude) and that of Capricorn (23º 26 ′ 12.9 ″ south latitude).

Distribution of tropical forests in the world. Source:

America

In America, 57% of the tropical forest is found, from southern Mexico to northern Argentina. The largest mass of tropical forest is made up of the jungle of the Amazon basin.

The Amazon rainforest extends for the most part through Brazilian territory and the rest is distributed between Bolivia, Peru, Colombia and Venezuela. Another great extension of tropical forests corresponds to the forests of the Guiana Shield (Venezuela, Brazil, Guyana, Suriname and French Guyana).

Africa

In Africa rainforests develop south of the Sahara desert to the savannas and shrubs bordering the Kalahari desert. The greatest extensions are in the tropical forests of the Congo and Madagascar.

The almost total extension of tropical forest on this continent is located in west-central Africa. This covers Cameroon, Gabon, the Central African Republic and the Republic of the Congo.

Asia

They are located in the Indo-Malay region in Southeast Asia, highlighting the equatorial jungle of Borneo. These forests are currently threatened by deforestation for timber and the cultivation of oil palm (Elaeis guinensis).

Oceania

Lowland rainforests and mountain rainforests are found in Papua New Guinea, New Caledonia, and northeast Australia. The rainforests of Queensland contain most of the remnants of the ancient forests of Gondwana.

Flora

One family that characterizes the popular image of the tropics is Palmae or Arecaceae, and species of palms can be found in almost all tropical rainforests. Other families are common among the tropical forests of America, Africa, Asia and Oceania such as legumes, gutiferous, moraceae and myrtaceae.

A characteristic element of the tropical forests of the world, especially the cloudy ones, are the tree ferns. These giant ferns are part of the understory of forests and belong to the Cyatheaceae family.

American rainforest

In the American tropical forests there are abundant species of legumes, meliaceae, moraceae, malvaceae and rubiaceae.

Among the legumes, species of the genera Albizia, Lonchocarpus, Anadenanthera, among others, stand out. In the meliaceae, the American cedar (Cedrela spp.) And mahogany (Swietenia macrophylla) which are fine wood trees.

In the moraceae family, species of the genus Ficus are of great importance and in malvaceae the ceiba (Ceiba pentandra). Rubiaceae are a highlight of the understory with herbs and shrubs.

In the Amazon there are species of lecitidaceae called monkey coco (Lecythis ollaria) and cap or cannonball (Couroupita guianensis).

Cacao (Theobroma cacao) is native to the Amazon basin, as well as pineapple (Ananas comosus) which is a roseate herb of the bromeliad family.

African rainforest

Trees adapted to these conditions are found in the swampy forests of the Congo. Among others, Entandrophragma palustre, Sterculia subviolacea and Manilkara and Garcinia species stand out.

Fruit tree species such as Dacryodes klaineana are found in the western African rainforest near the equator. Likewise, there are timber trees such as Strombosia glaucescens and medicinal trees such as Allanblackia floribunda.

The cola nut (Cola nitida) used in the production of cola soft drinks or sodas is native to these African jungles. One of the most abundant plant families are legumes such as Parkia bicolor, Parinari excelsa and Piptadeniastrum africanum.

Asian rainforest

In the swampy tropical forests of Vietnam there are species adapted to these conditions with stilt roots and pneumatophores. Respiratory roots (pneumatophores) are specialized anatomical structures for aeration.

Among others, species of Eugenia (Myrtaceae), Elaeocarpus (Elaeocarpaceae) and Calophyllum (Guttiferae) stand out.

Teak (Tectona grandis) is found in the tropical rainforests of Thailand and Malaysia, which is a tree with high quality oil and wood. Another important timber species is Xylia dolabriformis with a hard and highly valued wood.

In some forests, hardwood tree species belonging to the Dipterocarpaceae family dominate.

Oceania rainforest

In this region there are warm rainforests with a canopy up to 30 m high. Among the trees there are species such as Rhus taitensis, Alphitonia zizyphoides and Casuarina equisetifolia.

The understory is dominated by the staghorn fern (Dicranopteris linearis) and shrubs of Macropiper puberulum and Psychotria insularum. In Australia and New Zealand there are rainforests where the dominant element are Eucalyptus species (Myrtaceae).

Fauna

American rainforest

In these jungles inhabits the largest carnivore in tropical America, which is the jaguar or American tiger (Panthera onca). There is also one of the largest birds of prey in the world, the harpy eagle (Harpia harpyja).

Jaguar (Panthera onca). Source: USFWS

Similarly, there are two species of three-toed sloths (Bradypus tridactylus and Bradypus variegatus) and two two-toed sloths (Choloepus didactylus and Choloepus hoffmanni).

There are several species of primates such as the howler monkey (Alouatta spp.) And the spider monkey (Ateles spp.). Other mammals are the tapir or tapir (Tapirus terrestris) and the collared peccary (Pecari tajacu).

Among the birds, different species of toucan (ranfástidos family) and oropendola (Ortalis ruficauda) stand out.

Snakes include constrictors such as the emerald boa (Corallus caninus) and the swallowtail (Boa constrictor). Poisonous snakes such as the mapanare or nauyaca (Bothrops spp.) And the cuaima pineapple (Lachesis muta) also abound.

In the Andean high mountain jungles inhabits the only species of South American bear called the frontin or spectacled bear (Tremarctos ornatus).

African rainforest

It is the habitat of the leopard (Panthera pardus), the chimpanzee (Pan troglodytes and Pan paniscus) and the gorilla (Gorilla spp.). Likewise, you can find the jungle elephant (Loxodonta cyclotis) and the okapi (Okapia johnstoni).

Forest elephant (Loxodonta cyclotis) in the Congo (Africa). Source: Thomas Breuer

In the western rainforests (Liberia, Ivory Coast, Equatorial Guinea, Sierra Leone), there are Cafalophine cattle. In this group there are two species which are the Jentink duiker (Cephalophus jentinki) and the zebra duiker (Cephalophus zebra).

Within the Taï National Park (Ivory Coast) there are about 1,000 vertebrates, highlighting the pygmy hippopotamus (Hexaprotodon liberiensis). Among the poisonous snakes there is the black mamba (Dendroaspis spp.) And among the constrictors the python (Python regius).

In the jungles of Madagascar there are several species of lemurs endemic to that great island.

Asian rainforest

Borneo is home to the orangutan (Pongo pygmaeus), the Asian tapir (Tapirus indicus) and the clouded panther (Neofelis diardi) and in Sumatra the Sumatran orangutan (Pongo abelii). For their part, Thailand and Malaysia are home to the tiger (Panthera tigris) and the Asian elephant (Elephas maximus).

Oceania rainforest

Queensland's rainforests have a great diversity of marsupials and songbirds. There are also constrictor snakes of the python group (Antaresia spp.)

Weather

The intertropical region is characterized by what is called a tropical climate, characterized by high temperatures and high humidity. In turn, the tropical climate includes various climatic subtypes.

Of these, in the tropical forests we find a rainy equatorial climate, a monsoon climate and a humid-dry tropical climate.

Rainy equatorial climate

In the rain forests near the equator we find the rainy equatorial climate. This is characterized by high rainfall and high temperatures (annual average above 27 ºC).

This type of climate occurs in the Amazon rainforest, the Congo jungle, and the Malay jungles. In some places rainfall exceeds 5,000 mm per year as in the Freetown peninsula in Sierra Leone.

In the forests of Chocó (Colombia) rainfall of 13,000 to 16,000 mm per year is reached and at no time less than 3,000 mm.

Monsoon climate

They are areas under the influence of the monsoon (air masses coming from the ocean loaded with humidity from the east). It is similar to the equatorial climate in temperature and precipitation, but it is less rainy than is typical of the rainforests of Southeast Asia.

Humid-dry tropical climate

It is characterized by having a well-marked rainy season and a dry season with a similar duration. The temperatures are high, although it presents more oscillations than the equatorial climate.

This is the climate in which they develop, for example the semi-deciduous and deciduous tropical forests in America.

Relief

The tropical forests are located from alluvial plains at sea level, valleys and plateaus, to high mountains, reaching 3,700 meters above sea level. For example, the Amazon rainforest for the most part consists of rolling plains.

The cloud forest of the Andes mountain range extends from 900 meters to 3,600 meters above sea level. The westernmost tropical forests of Africa develop in undulating plains between 50 and 500 meters above sea level.

Economic activities

- Traditional activities

The ethnic groups traditionally settled in the tropical forests have practiced mainly hunting, fishing and gathering. These activities were carried out for subsistence purposes and are still carried out today.

Likewise, low intensity agriculture is practiced with rotation of the cultivation areas without greater use of agricultural inputs.

- Modern economy

With the development of the capitalist economy, the pressure on the tropical forests has increased. Among the high-impact activities for market purposes are deforestation for timber, livestock, and intensive crops.

Livestock and soy production in the Amazon

One of the serious threats to the Amazon is deforestation, which has a dual objective of obtaining fine woods and disposing of the land. Once the forest is deforested, pastures are established for the production of livestock.

Another growing activity in the cultivation of soybeans, especially for the production of biofuels.

The cultivation of oil palm (

Borneo's rainforests are being deforested at accelerating rates, especially for the cultivation of the African oil palm. This brings as a consequence the threat of extinction of numerous species such as the orangutan.

Conservation crops

There are some crops whose impact on the tropical forest is minor, such as coffee (Coffea arabiga) and cocoa (Theobroma cacao). These crops are established in the understory taking advantage of the shade provided by the jungle trees.

tourism

Tourism is an activity that, carried out properly, brings economic benefits and has a low environmental impact. In many rainforests in protected areas camps are established for ecotourism.

Rainforest in Mexico

Due to its geographical location between the Nearctic (North) and Neotropical (South) biogeographic kingdoms, Mexico has a diverse flora and fauna. To the north it has coniferous and mixed forests, while to the south there are tropical forests.

Due to the location of the tropical forests, the biogeographic provinces of the Gulf of Mexico, Yucatán and Chiapas are relevant. This corresponds to the southern states of Oaxaca, southern Veracruz, Chiapas, Tabasco, Campeche, Yucatán and Quintana Roo.

- Deciduous tropical forests and low flood forests

Deciduous rainforests

Deciduous forests are found in much of Yucatan and are dominated by species of legumes, euphorbiaceae, and sapotaceae.

Low floodplain forests

These form patches and inhabit species such as the pucté (Bucida buceras), Dalbergia spp. and the Campeche wood (Haematoxylum campechianum). Likewise, palms like Acoelorrhaphe wrightii can be found.

- Warm rain forest

The rainforests with a humid tropical climate and little topographic relief extend through the east and southeast of Mexico, occupying 11% of the national territory. A representative example of these jungles is the so-called Lacandon jungle in the state of Chiapas in southern Mexico.

Lacandona Jungle (Mexico). Source: Marrovi

There are species of precious woods such as mahogany (Swietenia macrophylla) and red cedar (Cedrela odorata). Likewise, palm species of the genus Scheelea and other economically important trees such as the chicozapote (Manilkara zapota).

Other important species are Bursera simaruba, Dendropanax arboreus, Sideroxylon tempisque, Pithecellobium arboreum and Ficus spp.

Fauna

Primates such as the spider monkey (Ateles geoffroyi) and the howler monkey (Alouatta palliata) live in these forests. There are also the arboreal anteater (Tamandua mexicana), the raccoon (Procyon lotor), the tapir (Tapirus bairdii) and the jaguar (Panthera onca).

Among the birds, the scarlet macaw (Ara macao), the hocofaisán (Crax rubra) and the royal toucan (Ramphastos sulfuratus) stand out.

- Mountain forests

To the south of Mexico there are exceptional montane forests, because it is the southern limit of gymnosperm species. In these mountains there is an annual precipitation of 2000 to 4000 mm and dense layers of clouds.

In these forests they mix conifers, temperate angiosperms and tropical angiosperms.

Transition between temperate forests and tropical rainforest

Representatives of the temperate forest are species of the genera Abies, Juniperus, Cupressus and Taxus. In addition, there are temperate climate (Quercus) and tropical angiosperms such as bromeliads, orchids and Persea trees.

Among the fauna are birds such as the quetzal (Pharomacrus mocinno mocinno) and the horned peacock (Oreophasis derbianus), which is in danger of extinction. Very remarkable is also the arboreal anteater (Tamandua mexicana).

Rainforest in Colombia

- Colombian Amazon rainforest

Like all the Amazon rainforest, it is about extensive plains where the distribution of vegetation is influenced by the great rivers. In this context, swampy and grassy areas develop, as well as low and high jungles.

The most abundant plant families are the Annonaceae, Lecythidaceae, Myristicaceae, Leguminosae, and Sapotaceae.

Swampy areas

In some areas, low-lying forests are established and species such as Cecropia membranacea and Annona hypoglauca dominate. In other parts there are scrubs of Montrichardia arborescens and various species of sedges.

Alluvial plain

There are areas where flooding is associated with the river's flood cycles and higher forests are established there. There is a predominance of species such as Inga nobilis and Aniba megaphylla and palm groves dominated by Mauritia flexuosa and Mauritiella aculeata.

Then on the low terraces you can find jungles with a canopy up to 30 m high. In this formation there are species of palms such as Oenocarpus bataua, a palm that produces an oil that is highly valued as a medicine.

Mainland jungle

Species such as Dialium guianensis, Phenakospermum guianensis and Leopoldinia spp. Also, various species of leguminous trees such as Swartzia schombugkii and Swartzia brachyrachis.

Fauna

Mammals such as the jaguar (Panthera onca), the tapir (Tapirus terrestris) and the collared peccary (Pecari tajacu) inhabit these forests. Among the reptiles are the anaconda (Eunectes murinus) and the black caiman (Melanosuchus niger) that can reach up to 6 meters in length.

- Chocó jungle

This jungle extends along the Colombian Pacific coast and a small area of ​​the western Caribbean coast. It is the continuation of the Panamanian Darien jungle and continues to Ecuador.

They are jungles that reach up to 35-40 m, with emergent trees up to 60 m high, such as the matapalo (Ficus dugandii).

Plant diversity

Around 4,525 species of spermatophytes (seed plants) grouped in 170 families have been reported. Of these, only three are gymnosperms of the families Gnetaceae (1 species), Podocarpaceae (3 species) and Zamiaceae (7 species).

Of the 167 families of angiosperms, the most diverse are the Rubiaceae (342 species), Orchidaceae (250 species) and Melastomataceae (225 species).

Fauna diversity

778 species of birds have been identified in the forests of Chocó and a great diversity of reptiles. Among the latter, the Caiman crocodilus and Crocodylus acutus and the snakes Boa constrictor and Lachesis muta stand out.

Regarding mammals, there are about 180 species of mammals, the most abundant groups being bats and rodents. There are 11 species of endemic mammals (exclusive) of this forest such as the Platyrrhinus chocoensis.

Among the larger mammals we find the jaguar (Panthera onca) and the tapir (Tapirus bairdii).

- Andean montane jungles

In the Colombian Andes mountain range we find humid mountain rainforests between 800 and 3,600 meters above sea level. This jungle has an upper canopy of up to 40 m, and two lower strata and the understory.

They are characterized by strong cloud cover for most of the year and high humidity.

Plant diversity

Epiphytes and climbing plants abound, mainly bromeliads, orchids, araceae, bignoniaceae and legumes. Rubiaceae, Arecaceae, Cyclanthaceae and Marantaceae are found in the understory.

The arboreal strata are dominated by legumes, Moraceae, Lauraceae, Cecropiaceae, among other families.

Fauna diversity

The jaguar (Panthera onca) also inhabits these forests and we find the frontin or spectacled bear (Tremarctos ornatus).

- Deciduous and semi-deciduous forests

In some areas of the lowlands there are dry, semi-deciduous and deciduous forests, particularly towards the Colombian Caribbean. Legumes, bignoniaceae and anacardiaceae are frequent in these forests.

Some common species are Ceiba pentandra, Astronium graveolens, Pithecellobium spp., Bulnesia arborea, Tabebuia spp., Handroanthus spp among others

References

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