RAINFOREST INFORMATION

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

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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

River culture is the rhythmic pulse of the Bengal Delta (commentary) (Jan 17 2025)
- Reviving rivers in Bangladesh is not simply an ecological issue, but also a socio-cultural one, and an economic imperative.
- The government and the people must come together to protect and restore the rivers, not just for environmental sustainability and justice, but also to preserve the rich heritage and cultural identity associated with these waterways, a new op-ed argues.
- This post is a commentary. The views expressed are those of the author, not necessarily Mongabay.

Bangladesh sees first ever rewilding of captive-bred elongated tortoises (Jan 17 2025)
Two species of critically endangered tortoises were reintroduced to Bangladesh’s forests last December. Six captive-bred elongated tortoises (Indotestudo elongata) were first released in Lawachara National Park in northeastern Bangladesh on Dec. 18. This was followed by the release of 10 Asian giant tortoises (Manouria emys phayrei) in Matamuhuri Reserve Forest in the Chittagong Hill Tracts of […]

Firefighters in LA blaze face same toxic exposure as 9/11 responders (Jan 17 2025)
Smoke from wildfire poses a host of health concerns, but when fires burn through urban areas, like the ongoing inferno in Los Angeles, U.S., the health risks increase dramatically. “This is an entirely different situation because the wildfire smoke is bad enough, but when synthetic materials burn, they’re going to give off more toxics, not only in […]

In Bangladesh, a botanist brings quick, fun lessons to social media (Jan 17 2025)
- A botany expert turned online educator in Bangladesh is proving that anyone can become a plant enthusiast, no educational degree required.
- With his short, snappy videos, Azharul Islam Khan has captivated around a million followers on social media, teaching them about the diversity of Bangladeshi plants and trees.
- His engaging content isn’t just for plant lovers; it’s building a diverse community of students, eco-conscious families and nature enthusiasts.
- Azharul is on a mission to protect the environment, advocating sustainable tree planting and educating the public about the importance of balanced ecosystems.

A venomous Australian spider turns out to be 3 species, not 1 (Jan 17 2025)
The Sydney funnel-web spider, a highly venomous arachnid found crawling in and around Australia’s most populous city, was long thought to be a single species. But it’s actually three different species, a new study has found. One of these, called “Big Boy” for its unusually large size, is new to science. “You would think we […]

Sustaining a 400-year-old Ethiopian farming tradition: Interview with elder Gehano Guchoir (Jan 17 2025)
- In southern Ethiopia, the Konso people have maintained a 400-year-old stone terracing system, essential for farming in the region’s semiarid environment.
- This UNESCO-listed practice helps prevent soil erosion, conserve water and enhance agricultural productivity, and at the heart of it are the Konso elders who play a crucial role in passing down the knowledge of terracing to younger generations.
- However, population growth and climate change threaten the survival of the terracing system, and with land becoming scarce, many young Konso people are migrating to cities, leaving behind traditional farming.
- Combined with the unpredictable impacts of climate change, this exodus risks severing the transmission of critical knowledge and weakening the community’s agricultural practices and cultural identity.

Plans for bauxite mine in Suriname reignite Indigenous land rights debate (Jan 16 2025)
- A bauxite mine run by Chinese corporation Chinalco could begin operating next year, endangering a 280,000-hectare (about 692,000 acres) area of western Suriname inhabited by Indigenous communities.
- The mine will require refurbishing and expanding infrastructure for a harbor and railroad built in the 1970s, and gives the company “priority right” to use the Corantijn river for dredging.
- Indigenous groups said they weren’t properly consulted about the project and that the government is unfairly labeling their territory as public domain.

Safeguarding the shea nut legacy for Ugandan women (Jan 16 2025)
KAL AWINYA, Uganda – In rural Uganda, 34-year-old Adong Betty from Kal Awinya village shares how shea nuts sustain her family and community. Her own childhood was marked by active participation in collecting and processing shea nuts with her mother, instilling in her a deep respect for this tradition. Shea nuts are a critical part […]

Should mining companies consider no-go zones where isolated Indigenous peoples live? (Commentary) (Jan 16 2025)
- Irresponsible mining for critical minerals, like those used in renewable technologies, can threaten the existence of Indigenous peoples in voluntary isolation, who are amongst the world’s most vulnerable populations.
- Companies like Tesla are considering no-go zones where uncontacted people live. While the idea of establishing these zones is increasingly pragmatic, the author says the most crucial thing for companies to do is conduct rigorous human rights due diligence from the initial stages of mine development right through to closure.
- Danielle Martin from the International Council on Mining and Metals (ICMM) says this approach relies on the meaningful and inclusive engagement and the participation of affected Indigenous peoples. But for Indigenous peoples in voluntary isolation, engagement and participation may not be possible and agreement may not be attainable.
- This article is a commentary. The views expressed are those of the authors, not necessarily Mongabay.

Ogoni women restore mangroves and livelihoods in oil-rich Niger Delta (Jan 16 2025)
- After decades of crude oil spills and the introduction of invasive plant species, thousands of hectares of mangroves in the Niger Delta are destroyed, impacting aquatic species and women’s livelihoods.
- Ogoni women from coastal villages, supported by the Lokiaka Community Development Centre, have been at the forefront of reforestation efforts.
- The women have planted 2.6 million mangrove trees since 2018, drawing attention from a government agency that hired them to share their knowledge and plant mangroves for its oil spill rehabilitation project.
- Around 300 women from Ogoni communities have been trained in mangrove reforestation.

Elephants, gorillas and chimps hold out in Cameroon’s largest protected landscape (Jan 16 2025)
- A new survey finds that populations of forest elephants, lowland gorillas and chimpanzees have remained relatively stable in a large landscape in southeastern Cameroon.
- In some cases, populations actually rose significantly in the region’s protected areas, but declined on the outskirts.
- Officials attribute this “positive” trend to hard work and the implementation of a “permanent presence technique” to deter poaching by engaging more closely with local communities.
- However, they say more effort is still needed to combat poaching for tusks and the trafficking of great apes.

Satellite ‘backpacks’ help keep track of parrot migration in Mexico (Jan 16 2025)
- Scientists and conservationists have deployed lightweight satellite backpacks, containing transmitters, to study and understand the migration patterns of thick-billed parrots.
- Teams from San Diego Zoo Wildlife Alliance in the U.S. and conservation NGO Organización Vida Silvestre in Mexico have gathered more than 70,000 data points over four years.
- The data helped them identify corridors that are critical for the birds’ movements; they also served to justify the designation of protected areas that are important for the birds.
- Thick-billed parrots, known for their raucous calls, are an endangered species endemic to Mexico; illegal logging in recent years has led to the degradation of their habitats.

Vested interests and social tribes in the Pan Amazon (Jan 16 2025)
- Local and regional actors, particularly commercial and landowner elites in mid-sized cities, play an important role in the expansion and improvement of road networks. In Brazil, lobbying by private interests played a big role in the development of Rodovia Transamazônica and BR-319.
- In Brazil, agribusinesses exert political power via the Frente Parlamentar da Agropecuária (FPA), often referred to as the Bancada Ruralista, a multi-party congressional voting bloc.
- One of the most significant accomplishment of the ruralistas was their 2012 campaign to modify Brazil’s the Forest Code. Changes included amnesty for property owners who had illegally deforested land before 2008 and adjusted requirements to reforest portions of landholdings that had exceeded legal deforestation limits.

African Parks closes deal to manage Ethiopia’s Gambella National Park (Jan 16 2025)
- South Africa-based conservation NGO African Parks signed a long-term deal in December 2024 to manage Gambella National Park in Ethiopia.
- The agreement brings the number of protected areas under management by African Parks to 23 in 13 countries.
- Gambella is part of a wider landscape that includes Boma and Badilingo national parks, across the border in South Sudan.
- The Gambella region has been conflict-prone in recent years, with a documented history of human rights violations by the Ethiopian government and other groups.

Mongabay documentary spotlights Indigenous alliance to protect Amazon headwaters (Jan 16 2025)
Mongabay’s new short documentary The Time of Water premiered Dec. 16 at the Barcelona Center for Contemporary Culture, in Spain. Directed by Pablo Albarenga and produced with support from the Pulitzer Center and OpenDemocracy, the 18-minute documentary explores the Amazon Sacred Headwaters Alliance and its fight to protect one of the world’s most vital sources […]