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

Do cheetahs scavenge? Yes, research says, but also not really (Jan 24 2025)
- Recently published research finds that cheetahs aren’t above scavenging other predators’ kills, contrary to the conventional wisdom that they only eat what they kill.
- Direct observations and by-catch data from carnivore research projects in three locations in South Africa and Malawi were used to gather information on cheetah scavenging.
- The researchers say that understanding these behavioral shifts is crucial for cheetah conservation, as successful reintroduction efforts depend on the ability of cheetahs to adapt to new environments and food acquisition strategies.
- However, other cheetah experts question how common this phenomenon is, given that the researchers only recorded three scavenging events between 2019 and 2023.

Salmon farms under fire on U.S. East Coast after being shuttered on West Coast (Jan 24 2025)
- An advocacy group has sued the last company in the U.S. still farming salmon in sea cages, citing alleged violations of the Clean Water Act.
- Cooke Aquaculture runs more than a dozen sites in the northeastern state of Maine. The lawsuit accuses the company of illegally discharging pollutants, exceeding limits on effluents and nutrient buildup, and reporting violations.
- The legal action comes the same month that the state of Washington became the last on the West Coast to ban industrial salmon aquaculture over environmental concerns, making Maine the only U.S. state where the practice continues.
- Critics argue that netpen salmon farming not only pollutes the marine environment but also threatens wild salmon populations, while requiring the harvest of too much wild fish and krill for feed.

World’s tiniest transmitter finds nesting area of rarest migratory shorebird (Jan 24 2025)
Using the world’s smallest known satellite transmitter, conservationists were able to track a spoon-billed sandpiper, thought to be the world’s rarest migratory shorebird. The transmitter  revealed new stopovers and nesting areas for an individual known as K9. “K9 led us to a newly discovered breeding location and habitat, which could be a game-changer for Spoon-billed […]

‘We’re getting back on track’: Interview with IBAMA head Rodrigo Agostinho (Jan 24 2025)
- Rodrigo Agostinho, head of IBAMA, Brazil’s federal environmental agency, for two years now, spoke with Mongabay about the progress of his agency and the challenges it faces in protecting the country’s biomes after four years of regression under former president Jair Bolsonaro.
- Agostinho revealed plans to strengthen the agency and try to reach the 2030 zero-deforestation goal before the deadline, with investments in cutting-edge technology and artificial intelligence: “IBAMA went four years without using satellite images for embargoes. We’ve taken that up again with full force”.
- Agostinho also detailed IBAMA’s restructuring plans, with the opening of offices in the Amazon and support from financial authorities to cut off funding for embargoed areas: “We embargo them due to deforestation, and then that person can’t get agricultural financing anymore.”

China’s new pangolin quota for TCM sparks conservation concerns (Jan 24 2025)
- China has announced an annual quota of 1 metric ton of pangolin scales for medicinal use, raising concerns among conservationists about potential illegal trafficking despite this being a significant reduction from past quotas.
- Conservationists question the legality and transparency of China’s pangolin scale stockpiles, as the reported quantities remain undisclosed and appear undiminished, fueling suspicions of illegally sourced scales entering the legal market.
- Although China has implemented measures like elevating pangolin protection and removing scales as raw ingredients for traditional medicine, loopholes in its Wildlife Protection Law and continued domestic trade create risks for illegal activity.
- Conservationists warn that China’s policies, combined with a lack of transparency and oversight, undermine efforts to curb pangolin trafficking, threatening what is already the world’s most trafficked mammal.

Digitizing 6 million plant specimens: Interview with Gunter Fischer & Jordan Teisher (Jan 24 2025)
- Researchers at Missouri Botanical Garden in the U.S. have launched an initiative to create a digital repository of the 6 million plant specimens stored in the herbarium there.
- The six-year Revolutionizing Species Identification initiative aims to combine data obtained from visual and hyperspectral scanning with artificial intelligence to build up a plant repository unlike any before.
- The team behind the project says they hope the reference database will speed up plant identification; it could also potentially be used to gauge the health of forests in the face of climate change.

Coming to a retailer near you: Illegal palm oil from an orangutan haven (Jan 24 2025)
- A surge of deforestation for oil palm plantations in a Sumatran orangutan reserve means top consumer brands may be selling products with illegal oil palm in them, a new report says.
- Rainforest Action Network (RAN) says satellite imagery shows much of the deforestation in Rawa Singkil Wildlife Reserve occurred from 2021 onward.
- That means any palm oil produced from plantations established on land cleared during that time would be banned from entering the European market under the EU’s antideforestation regulation (EUDR).
- Brands such as Procter & Gamble and palm oil traders like Musim Mas have responded to the findings by dropping as suppliers the mills alleged to be processing palm fruit from the deforested areas.

In Uganda, a women-led reforestation initiative fights flooding, erosion (Jan 23 2025)
- Changing rainfall patterns have led to increasingly frequent flooding in western Uganda’s Kasese district, destroying farmers’ homes and fields.
- The damage is exacerbated by the loss of tree cover, as many trees have been cut down by locals for firewood.
- Janet Nyakairu Abwoli from Kasese organizes workshops to teach women how to plant and care for trees, particularly Dracaena and Ficus species.
- These native species can help prevent erosion of slopes and riverbanks, retain soil moisture, and provide fodder for small livestock and ingredients for traditional medicine.

Scientists are tracking global wildlife’s contributions to humanity (Jan 23 2025)
- New research assesses in detail the contributions of wildlife to people.
- Humanity relies on an array of ecosystem services for well-being and survival, but the provision of these services rely not just on vegetation but also the wild animals that inhabit the same ecosystems.
- They found that vertebrate wildlife on land and in freshwater and marine environments support 12 of the 18 categories of nature’s contributions to people set forth by the U.N.’s Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services.
- The authors say that accounting for wildlife along with measures of ecosystems such as vegetation cover will provide a more complete picture of their health and help guide decision-making aiming to ensure that those ecosystems continue to provide critical services to people.

Record seizure highlights scale of wild bird egg theft in UK (Jan 23 2025)
Police in the U.K. recently announced the seizure of more than 5,000 eggs belonging to several wild bird species, following nationwide raids in November 2024. While no arrests have been made in this case, the investigations are continuing. The seizure, the largest of its kind in U.K. history, was part of an international crackdown on […]

In the Pan Amazon, inequality and informality fuel informal economies (Jan 23 2025)
- In the mid-twentieth century, the combination of poverty and inequality generated political instability that gave rise to socialist and nationalist movements in different Amazonian countries.
- In societies as stratified as those of the Pan Amazon, shaped by class, ethnicity and geography, inequality is sustained by very real and concrete structural barriers.
- This has resulted in the exponential growth of the informal economy, in which people do not pay taxes to their governments. Irregularities extend to the rural economy, in which smallholder farmers and miners operate without regulation, often damaging ecosystems.

In Panama, major port construction begins at key mangrove site (Jan 23 2025)
- The Puerto Barú project, located outside the town of David in the Pacific province of Chiriquí, will be a new industrial port on Panama’s west coast, where channels and lagoons support mangroves, breeding grounds and nurseries for a variety of marine species.
- The project requires dredging a riverbed and increasing maritime traffic of cargo ships, cruise ships and yachts.
- More than 50 conservation groups have organized a “No to Puerto Barú” campaign, but an initial injunction to stop construction was shot down in court.

US set to lose out as Trump retreats from climate agreement, NGOs warn (Jan 23 2025)
U.S. President Donald Trump kicked off his second term in office by issuing an executive order withdrawing the U.S. from the 2015 Paris climate accords, a historic agreement to limit global warming to below 2° Celsius (3.6° Fahrenheit) above pre-industrial levels. The order states that it’s the policy of the new administration to put U.S. […]

Mexico misses one-year deadline to submit new protected areas’ management plans (Jan 23 2025)
- Exactly one year ago, Mexico announced 20 new protected areas covering roughly 2.3 million hectares (5.7 million acres) across the country.
- According to Mexican law, the environment ministry has one year to publish a protected area’s management plan after a decree is issued, but Mongabay found that none of the 20 protected areas have management plans yet.
- Scientists, conservationists and communities have been pushing for these plans to be published, concerned that the absence of a roadmap means these areas are still vulnerable to threats and overexploitation.
- Some National Commission of Natural Protected Areas (CONANP) officials and researchers told Mongabay the delay was due to a change in Mexico’s leadership, funding concerns, a historic backlog and other issues.

Birdwatchers rally behind endemic hummingbird, spurring conservation movement in Mexico (Jan 23 2025)
- In Veracruz, the charismatic Mexican sheartail, one of the 58 hummingbird species in the country, is threatened by habitat loss due to deforestation for agriculture and urbanization.
- Chavarillo, an important spot for migratory birds, located in central Veracruz, has leveraged income gained from birdwatching to create a natural reserve for the Mexican sheartail.
- One local in Chavarillo donated land to establish the Doricha Natural Reserve, which provides the sheartail with much needed habitat and helps promote biodiversity conservation more widely.
- Birdwatchers, local landowners and conservationists have come together here to protect a habitat and ecosystem important for many endemic species.