RAINFOREST INFORMATION

A Place Out of Time: Tropical Rainforests and the Perils They Face - information on tropical forests, deforestation, and biodiversity

Sections:

BACKGROUND INFORMATION ON THE RAINFOREST

Rainforests are forest ecosystems characterized by high levels of rainfall, an enclosed canopy and high species diversity. While tropical rainforests are the best-known type of rainforest and the focus of this section of the web site, rainforests are actually found widely around the world, including temperate regions in Canada, the United States, and the former Soviet Union.

Tropical rainforests typically occur in the equatorial zone between the Tropic of Cancer and Tropic of Capricorn, latitudes that have warm temperatures and relatively constant year-round sunlight. Tropical rainforests merge into other types of forest depending on the altitude, latitude, and various soil, flooding, and climate conditions. These forest types form a mosaic of vegetation types which contribute to the incredible diversity of the tropics.

The bulk of the world's tropical rainforest occurs in the Amazon Basin in South America. The Congo Basin and Southeast Asia, respectively, have the second and third largest areas of tropical rainforest. Rainforests also exist on some the Caribbean islands, in Central America, in India, on scattered islands in the South Pacific, in Madagascar, in West and East Africa outside the Congo Basin, in Central America and Mexico, and in parts of South America outside the Amazon. Brazil has the largest extent of rainforest of any country on Earth.

Rainforests provide important ecological services, including storing hundreds of billions of tons of carbon, buffering against flood and drought, stabilizing soils, influencing rainfall patterns, and providing a home to wildlife and Indigenous people. Rainforests are also the source of many useful products upon which local communities depend.

While rainforests are critically important to humanity, they are rapidly being destroyed by human activities. The biggest cause of deforestation is conversion of forest land for agriculture. In the past subsistence agriculture was the primary driver of rainforest conversion, but today industrial agriculture — especially monoculture and livestock production — is the dominant driver of rainforest loss worldwide. Logging is the biggest cause of forest degradation and usually proceeds deforestation for agriculture.

Organization of this site

The rainforest section of Mongabay is divided into ten "chapters" (the original text for the site was a book, but has since been adapted for the web), with add-on content in the form of special focal sections (e.g. The Amazon, the Congo, REDD, New Guinea, Sulawesi, Forests in Brazil, etc), appendices, and other resources.

There is also a version of the site geared toward younger readers at kids.mongabay.com.

ABOUT THE RAINFOREST (SUMMARY)

RAINFOREST DISTRIBUTION AND CHARACTERISTICS

Each rainforest is unique, but there are certain features common to all tropical rainforests.

• Location: rainforests lie in the tropics.
• Rainfall: rainforests receive at least 80 inches (200 cm) of rain per year.
• Canopy: rainforests have a canopy, which is the layer of branches and leaves formed by closely spaced rainforest trees some 30 meters (100 feet) off the ground. A large proportion of the plants and animals in the rainforest live in the canopy.
• Biodiversity: rainforests have extraordinarily highs level of biological diversity or “biodiversity”. Scientists estimate that about half of Earth's terrestrial species live in rainforests.
• Ecosystem services: rainforests provide a critical ecosystem services at local, regional, and global scales, including producing oxygen (tropical forests are responsible for 25-30 percent of the world's oxygen turnover) and storing carbon (tropical forests store an estimated 229-247 billion tons of carbon) through photosynthesis; influencing precipitation patterns and weather; moderating flood and drought cycles; and facilitating nutrient cycling; among others.

The global distribution of tropical rainforests can be broken up into four biogeographical realms based roughly on four forested continental regions: the Afrotropical, the Australiasian, the Indomalayan/Asian, and the Neotropical. Just over half the world's rainforests lie in the Neotropical realm, roughly a quarter are in Africa, and a fifth in Asia.

These realms can be further divided into major tropical forest regions based on biodiversity hotspots, including:

1. Amazon: Includes parts of Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname, Venezuela
2. Congo: Includes parts of Cameroon, Central African Republic, Democratic Republic of the Congo, Equatorial Guinea, Gabon, Republic of Congo
3. Australiasia: Includes parts of Australia, Indonesian half of New Guinea, Papua New Guinea
4. Sundaland: Includes parts of Brunei, Indonesia, Malaysia, Singapore
5. Indo-Burma: Includes parts of Bangladesh, Cambodia, China, India, Laos, Myanmar, Thailand, Vietnam
6. Mesoamerica: Includes parts of Belize, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama
7. Wallacea: Sulawesi and the Maluku islands in Indonesia
8. West Africa: Includes parts of Benin, Cameroon, Côte d'Ivoire, Ghana, Guinea, Liberia, Nigeria, Sierra Leone, Togo
9. Atlantic forest: Includes parts of Argentina, Brazil, Paraguay
10. Choco: Includes parts of Colombia, Ecuador, Panama

Other countries that have large areas of rainforest include Bolivia, Cameroon, Central African Republic, Ecuador, Gabon, Guyana, India, Laos, Malaysia, Mexico, Myanmar, Papua New Guinea, Republic of Congo, Suriname, and Venezuela.

Cover and loss by rainforest region

RAINFOREST STRUCTURE

Rainforests are characterized by a unique vegetative structure consisting of several vertical layers including the overstory, canopy, understory, shrub layer, and ground level. The canopy refers to the dense ceiling of leaves and tree branches formed by closely spaced forest trees. The upper canopy is 100-130 feet above the forest floor, penetrated by scattered emergent trees, 130 feet or higher, that make up the level known as the overstory. Below the canopy ceiling are multiple leaf and branch levels known collectively as the understory. The lowest part of the understory, 5-20 feet (1.5-6 meters) above the floor, is known as the shrub layer, made up of shrubby plants and tree saplings.

RAINFOREST BIODIVERSITY

Tropical rainforests support the greatest diversity of living organisms on Earth. Although they cover less than 2 percent of Earth’s surface, rainforests house more than 50 percent of the plants and animals on the planet.

THE RAINFOREST CANOPY

In the rainforest most plant and animal life is not found on the forest floor, but in the leafy world known as the canopy. The canopy, which may be over 100 feet (30 m) above the ground, is made up of the overlapping branches and leaves of rainforest trees. Scientists estimate that more than half of life in the rainforest is found in the trees, making this the richest habitat for plant and animal life.

The conditions of the canopy are markedly different from the conditions of the forest floor. During the day, the canopy is drier and hotter than other parts of the forest, and the plants and animals that live there have adapted accordingly. For example, because the amount of leaves in the canopy can make it difficult to see more than a few feet, many canopy animals rely on loud calls or lyrical songs for communication. Gaps between trees mean that some canopy animals fly, glide, or jump to move about in the treetops. Meanwhile plants have evolved water-retention mechanisms like waxy leaves.

Scientists have long been interested in studying the canopy, but the height of trees made research difficult until recently. Today the canopy is commonly accessed using climbing gear, rope bridges, ladders, and towers. Researchers are even using model airplanes and quadcopters outfitted with special sensors — conservation drones — to study the canopy.

The rainforest floor

The rainforest floor is often dark and humid due to constant shade from the leaves of canopy trees. The canopy not only blocks out sunlight, but dampens wind and rain, and limits shrub growth.

Despite its constant shade, the ground floor of the rainforest is the site for important interactions and complex relationships. The forest floor is one of the principal sites of decomposition, a process paramount for the continuance of the forest as a whole. It provides support for trees responsible for the formation of the canopy and is also home to some of the rainforest's best-known species, including gorillas, tigers, tapirs, and elephants, among others.

Rainforest waters

Tropical rainforests support some of the largest rivers in the world, like the Amazon, Mekong, Negro, Orinoco, and Congo. These mega-rivers are fed by countless smaller tributaries, streams, and creeks. For example, the Amazon alone has some 1,100 tributaries, 17 of which are over 1,000 miles long. Although large tropical rivers are fairly uniform in appearance and water composition, their tributaries vary greatly.

Rainforest waters are home to a wealth of wildlife that is nearly as diverse as the biota on land. For example, more than 5,600 species of fish have been identified in the Amazon Basin alone.

But like rainforests, tropical ecosystems are also threatened. Dams, deforestation, channelization and dredging, pollution, mining, and overfishing are chief dangers.

Rainforest people

Tropical rainforests have long been home to tribal peoples who rely on their surroundings for food, shelter, and medicines. Today very few forest people live in traditional ways; most have been displaced by outside settlers, have been forced to give up their lifestyles by governments, or have chosen to adopt outside customs.

Of the remaining forest people, the Amazon supports the largest number of Indigenous people living in traditional ways, although these people, too, have been impacted by the modern world. Nonetheless, Indigenous peoples' knowledge of medicinal plants remains unmatched and they have a great understanding of the ecology of the Amazon rainforest.

In Africa there are native forest dwellers sometimes known as pygmies. The tallest of these people, also called the Mbuti, rarely exceed 5 feet in height. Their small size enables them to move about the forest more efficiently than taller people.

There are few forest peoples in Asia living in fully traditional ways. The last nomadic people in Borneo are thought to have settled in the late 2000's. New Guinea and the Andaman Islands are generally viewed as the last frontiers for forest people in Asia and the Pacific.

Deforestation

In recent decades there has been an important shift in deforestation trends. Today export-driven industries are driving a bigger share of deforestation than ever before, marking a shift from previous decades, when most tropical deforestation was the product of poor farmers trying to put food on the table for their families. There are important implications from this change. While companies have a greater capacity to chop down forests than small farmers, they are more sensitive to pressure from environmentalists. Thus in recent years, it has become easier—and more ethical—for green groups to go after corporations than after poor farmers.

Rainforests are also threatened by climate change, which is contributing to droughts in parts of the Amazon and Southeast Asia. Drought causes die-offs of trees and dries out leaf litter, increasing the risk of forest fires, which are often set by land developers, ranchers, plantation owners, and loggers.

Rainforest importance

While rainforests may seem like a distant concern, they are critically important for our well-being. Rainforests are often called the lungs of the planet for their role in absorbing carbon dioxide, a greenhouse gas, and producing oxygen, upon which all animals depend for survival. Rainforests also stabilize climate, house incredible amounts of plants and wildlife, and produce nourishing rainfall all around the planet.

Rainforests:

• Help stabilize the world’s climate: Rainforests help stabilize the world’s climate by absorbing carbon dioxide from the atmosphere. Scientists have shown that excess carbon dioxide in the atmosphere from human activities is contributing to climate change. Therefore, living rainforests have an important role in mitigating climate change, but when rainforests are chopped down and burned, the carbon stored in their wood and leaves is released into the atmosphere, contributing to climate change.
• Provide a home to many plants and animals: Rainforests are home to a large number of the world’s plant and animals species, including many endangered species. As forests are cut down, many species are doomed to extinction.
• Help maintain the water cycle: The role of rainforests in the water cycle is to add water to the atmosphere through the process of transpiration (in which plants release water from their leaves during photosynthesis). This moisture contributes to the formation of rain clouds, which release the water back onto the rainforest. In the Amazon, 50-80 percent of moisture remains in the ecosystem’s water cycle. When forests are cut down, less moisture goes into the atmosphere and rainfall declines, sometimes leading to drought. Rainforests also have a role in global weather patterns. For example researchers have shown that forests in South America affect rainfall in the United States, while forests in Southeast Asia influence rain patterns in southeastern Europe and China. Distant rainforests are therefore important to farmers everywhere.
• Protect against flood, drought, and erosion: Rainforests have been compared to natural sponges, moderating flood and drought cycles by slowing run-off and contributing moisture to the local atmosphere. Rainforests are also important in reducing soil erosion by anchoring the ground with their roots. When trees are cut down there is no longer anything to protect the ground, and soils are quickly washed away with rain. On steep hillsides, loss of forest can trigger landslides.
• Are a source for medicines and foods and support forest-dependent people: People have long used forests as a source of food, wood, medicine, and recreation. When forests are lost, they can no longer provide these resources. Instead people must find other places to get these goods and services. They also must find ways to pay for the things they once got for free from the forest.

Rainforest conservation

Rainforests are disappearing very quickly. The good news is there are a lot of people who want to save rainforests. The bad news is that saving rainforests will be a challenge as it means humanity will need to shift away from business-as-usual practices by developing new policies and economic measures to creative incentives for preserving forests as healthy and productive ecosystems.

Over the past decade there has been considerable progress on several conservation fronts. Policymakers and companies are increasingly valuing rainforests for the services they afford, setting aside large blocks of forests in protected areas and setting up new financial mechanisms that compensate communities, state and local governments, and countries for conserving forests. Meanwhile, forest-dependent people are gaining more management control over the forests they have long stewarded. Large international companies are finally establishing policies that exclude materials sourced via deforestation. People are abandoning rural areas, leading to forest recovery in some planes.

But the battle is far from over. Growing population and consumption means that rainforests will continue to face intense pressures. At the same time, climate change threatens to dramatically alter temperatures and precipitation patterns, potentially pushing some forests toward critical tipping points.

Thus the future of the world's rainforests in very much in our hands. The actions we take in the next 20 years will determine whether rainforests, as we currently know them, are around to sustain and nourish future generations of people and wildlife.

The Latest News on Rainforests

Without vultures, carcasses are slow to rot and disease-carrying flies abound (May 22 2025)
- Researchers in Costa Rica found that pig carcasses decomposed twice as fast when vultures had access to them compared to carcasses where vultures were excluded.
- The absence of vultures led to a doubling of fly populations at carcass sites, which could affect human health, since these flies can carry diseases like botulism and anthrax, and antibiotic-resistant bacteria.
- Unlike temperate regions with diverse scavenger communities, the neotropical forest system showed vultures as the primary vertebrate decomposers, with few other animals eating carcasses.
- The study highlights a major research gap since neotropical vultures are represented in only 7% of existing vulture literature, despite facing similar conservation threats as Old World vultures, like habitat loss, poisoning and power line collisions.

On Amazon destruction, will Brazil President Lula’s ‘disinformation space’ be penetrated? (commentary) (May 22 2025)
- Brazil’s President Lula apparently lives in a “disinformation space” surrounded by ministers promoting projects that destroy the Amazon Rainforest and lock in petroleum extraction for decades to come, a new opinion piece argues.
- Among these projects are the BR-319 highway and its associated side roads; the distribution of government land to known deforesters; and opening new oilfields at the mouth of the Amazon River.
- Lula’s support for these proposals is leading Brazil to a climate catastrophe that would devastate the country, the author writes, and the two key ministers who should be the ones to explain to the president the consequences of these projects are apparently not penetrating Lula’s disinformation space.
- This post is a commentary. The views expressed are those of the author, not necessarily of Mongabay.

Indigenous rights advocates petition to overturn Indonesian conservation law (May 22 2025)
- In Indonesia, where state-designated conservation areas often overlap with customary territories, Indigenous peoples have faced prosecution and imprisonment for living in and managing their ancestral lands as they always have.
- Many hoped a new 2024 conservation law would recognize the rights of Indigenous peoples to manage their lands; instead, the law continues to sideline communities and potentially criminalizes their traditional practices, despite scientific evidence that Indigenous peoples are among the most effective stewards of nature.
- Indigenous rights proponents say the new law was passed without meaningful participation of Indigenous peoples, and several groups have filed a judicial review petition with the Constitutional Court, seeking to overturn the new law.

Tropical forest loss hit new heights in 2024; fire a major driver in Latin America (May 21 2025)
- A new dataset and analysis released by World Resources Institute finds global tropical forest loss jumped to a record high in 2024, with 6.7 million hectares (16.6 million acres) worldwide.
- In total, the area of forest lost in 2024 is nearly the size of Panama.
- For the first time, fire, not agriculture, was the primary driver of primary tropical forest loss, with Latin America badly hit.
- Non-fire related tropical forest loss also increased, by 14%.

Why biological diversity should be at the heart of conservation (May 21 2025)
For the last several decades, global biodiversity has been in crisis. Yet, as we celebrate International Day for Biodiversity on May 22, which commemorates the adoption of the Convention on Biological Diversity, a global treaty, we offer some recent Mongabay stories highlighting lessons from undoing past harms and conserving biodiversity for our planet’s future. What […]

In New Guinea, megadiverse lowland forests are most at risk of deforestation (May 21 2025)
- Located at the edge of the western Pacific Ocean, New Guinea is a vast island where the biota of Asia and Australasia meet, making it a melting pot of unique plants and animals that occur nowhere else on the planet.
- Development pressure is ramping up across the island, however, opening up landscapes to new roads, industrial logging and agricultural conglomerates pushing biofuel agendas.
- New Guinea’s low-elevation forests, which represent some of the world’s last vestiges of ancient lowland tropical rainforest, are particularly imperiled, according to a new study.
- To avert tragedy, the authors urge policymakers to improve land-use planning systems, focus on retaining intact forest landscapes, and strengthen the rights of the people who live among them.

Deforestation in REDD-protected Congo rainforests is ‘beyond words’ (May 20 2025)
The Republic of Congo had been protecting about half of its dense rainforests via the Reducing Emissions from Deforestation and forest Degradation (REDD+) framework. In exchange, the country is supposed to receive payments from the World Bank. But Mongabay Africa staff writer Elodie Toto’s recent investigation revealed the nation has also granted nearly 80 gold […]

Brazil rewilds urban forest with vaccinated brown howler monkeys (May 20 2025)
Following a deadly yellow fever outbreak in 2016, brown howler monkeys are slowly making a recovery through targeted vaccination and reintroduction efforts in one of the world’s largest urban forests. The recovery is detailed in a Mongabay video by Kashfi Halford and a report by Bernardo Araujo. Brown howler monkeys (Alouatta guariba) are endemic to […]

Study unveils mystery of monkey yodeling — and why humans can’t compete (May 16 2025)
- Researchers found that New World monkeys can produce extreme yodeling-like sounds by rapidly switching between their vocal folds (for low tones) and specialized vocal membranes (for high tones), achieving frequency jumps up to 12 times greater than humans can manage.
- Scientists conducted their research at Bolivia’s La Senda Verde animal refuge, using recordings and electroglottographs on live monkeys.
- Humans lost these vocal membranes during evolution, trading vocal gymnastics for more stable speech that’s easier to understand.
- The complex vocalizations likely help monkeys manage social relationships and grab attention in the rainforest.

Republic of Congo’s gold mining boom undermines conservation efforts (May 16 2025)
The Republic of Congo has one of the lowest deforestation rates in the world, but “uncontrolled gold mining” in recent years could harm the country’s biodiversity, especially in the Sangha region, Mongabay’s Elodie Toto reported in a video published in February. Sangha, located in the country’s north, on the border with Cameroon and the Central […]

Profit imbalance in palm oil industry risks environmental compliance, report says (May 15 2025)
- A new report calls on palm oil-buying firms to take serious steps to address systemic imbalances in the distribution of profits across the supply chain.
- Smallholder farmers produce nearly one-third of raw palm oil globally, yet they receive a disproportionately small share of industry profits compared to large corporations, the report says.
- Small-scale producers are often locked out of high-value markets due to a lack of technical capacity and financial capital to meet increasingly hefty due diligence requirements driven by consumer demand for less environmentally destructive goods.
- The authors urge industry buyers to adjust their purchasing policies to be more inclusive of smallholder farmers, helping to create an industry that is more socially responsible and less environmentally destructive.

Brazil antideforestation operation blacklists more than 500 farms in the Amazon (May 15 2025)
The Brazilian government blocked 545 rural properties in the Amazonian state of Pará from selling crops and livestock both domestically and internationally, citing illegal deforestation, according to a May 6 announcement by the Ministry of Environment and Climate Change. The announcement marks one of Brazil’s largest uses of remote sensing to sanction agriculture activity associated […]

Malagasy wildlife champion wins top global conservation award (May 15 2025)
Malagasy scientist Lily-Arison René de Roland has been announced as the winner of this year’s Indianapolis Prize, which recognizes “extraordinary contributions to conservation efforts.” In its announcement, Indianapolis Zoo, which presents the award, highlighted René de Roland’s scientific and conservation work that has led to the discovery of several species and the establishment of four […]

Sumatran tiger protection needs more patrols, tougher penalties, study finds (May 15 2025)
- A new study on Sumatran tiger conservation in Indonesia’s Gunung Leuser National Park underscores that poaching remains the top threat, despite extensive patrols and antitrafficking efforts over the past decade.
- Researchers found that while patrols removed hundreds of snares and law enforcement increasingly pursued criminal charges, poaching rates remained high and tiger populations continued to decline in some areas.
- Despite stricter conservation laws and improved prosecution rates, the financial rewards of poaching still outweigh the penalties, limiting the deterrent effect on poachers and traffickers.
- The study recommends increasing patrols in high-risk areas, improving community engagement in law enforcement, and providing alternative livelihoods to reduce the economic lure of poaching.

Borneo project hopes to prove that forests and oil palms can coexist (May 15 2025)
- Monoculture palm oil production has come at the cost of rainforest habitat, particularly in Malaysia and Indonesia.
- Researchers are conducting experimental trials in Malaysian Borneo to see if native trees can be planted in oil palm plantations without significantly reducing palm oil yields.
- While still in the initial stages, the experiment is so far showing there are no detrimental effects to oil palm growth.
- In fact, interplanting with native forest trees may benefit oil palm, with the researchers finding oil palm trees had more leaf growth in agroforestry plots than in monoculture ones.