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

‘Protection too small, pressure too high’ for tree species globally, study finds (Aug 11 2022)
- Researchers looked at the distributions of more than 46,000 tree species around the world and found that more than 13% have no protection. For all species examined, at least half of their distribution lacks protection.
- Further, almost 15% of all species are exposed to high or very high human pressure and 68% to moderate pressure.
- The study goes beyond this assessment to explore which areas need to be protected worldwide to provide maximum benefit for tree diversity.
- Researchers found that the existing plan that would most effectively protect tree diversity is The Global 200, a list of ecoregions identified as priorities for conservation by WWF.

In Indonesia’s forest fire capital, the dry season brings yet more burning (Aug 5 2022)
- The onset of the dry season in Indonesia’s Riau province has seen flare up and multiply, some of them believed to have been set deliberately.
- More than 1,000 hectares (2,500 acres) of land has burned so far this year, a sharp increase from the 169 hectares (417 acres) in the first three months of 2022.
- The number of fires has prompted the provincial government to declare an emergency status and call for urgent measures, including cloud seeding to induce rainfall.
- Police have arrested nine people for suspected arson; although the practice is banned by law, farmers and plantation operators often use fire as a cheap tool to clear their concessions of vegetation ahead of planting.

Billions rely on wild species for food, energy and more: IPBES report (Aug 5 2022)
- A recently released summary of an assessment from the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) reveals that people rely on 50,000 wild species of plants, animals, algae and fungi.
- But it warns that the global biodiversity crisis threatens the sustenance and services that these species provide.
- According to the assessment, more than 10,000 wild species alone provide humans with food, and 2.4 billion people rely on fuelwood, often from wild-growing trees, to cook.
- Leaders of the assessment say they expect their findings to contribute to biodiversity conservation discussions at the U.N. biodiversity conference in December.

Big banks fund the heavy machinery used for Amazon deforestation, report says (Aug 4 2022)
- A new report from investigative outlet Repórter Brasil describes how the demand for heavy machinery like bulldozers, excavators and tractors is accelerating deforestation in the Brazilian Amazon.
- Heavy machinery is present at most steps of the process of nearly every activity driving deforestation, including cattle ranching, industrial agriculture and mining, among others.
- A lack of oversight by the government, manufacturers and the banks providing loans for the purchase of the machinery means that almost anyone can acquire one for any purpose.
- The report suggests that GPS tracking technologies be implemented for all heavy machinery and that banks carry out more rigorous due diligence measures.

Indigenous activists in Borneo claim win as logging firm removes equipment from disputed area (Aug 2 2022)
- After NGOs captured satellite and drone imagery they said showed timber firm Samling operating in deep forest and culturally sensitive sites in the Malaysian Bornean state of Sarawak, Indigenous activists filed a police report and planned to mount a blockade July 16.
- According to Penan Indigenous organization Keruan, the firm removed its equipment by July 15, a move the organization counts as a win for forest conservation.
- The area is slated for inclusion in the Upper Baram Forest Area (UBFA), a new conservation project led by the government and approved by the International Tropical Timber Organization.
- Samling denies encroaching on recognized Indigenous land, and said the UBFA has not been approved by the government or discussed with the company, which holds the timber concession for the most of the forest included in the project area.

Violence persists in Amazon region where Pereira and Phillips were killed (Aug 2 2022)
- Armed illegal gold miners on July 15 threatened government rangers near the site where British journalist Dom Phillips and Brazilian Indigenous expert Bruno Pereira were killed in June.
- Days after the threats, federal prosecutors charged three men in the killing of Phillips and Pereira, but activists and lawmakers say the investigation needs to be expanded to identify the possible involvement of criminal organizations.
- Activists say threats against government officials, including Pereira, have happened for decades, but that the situation has grown dire under President Jair Bolsonaro.
- The government’s weakening of environmental agencies and Bolsonaro’s anti-Indigenous rhetoric have created a sense of impunity, emboldening criminals in the Amazon to retaliate against activists and environmentalists who expose their illicit activities, experts say.

A utopia of clean air and wet peat amid Sumatra’s forest fire ‘hell’ (Aug 1 2022)
- Sadikin, a resident of Indonesia’s Riau province, converted his parents’ abandoned vegetable garden into an arboretum of peat-friendly tree species.
- In 2020, he won an award for his dedication to local firefighting efforts, including his innovation to dig shallow “hydrant” wells to speed up firefighting in peatlands.
- Sadikin and his fellow villagers have also adapted their pineapple cultivation system to include firebreaks, and use their crop to weave containers that can replace plastic bags.

Delectable but destructive: Tracing chocolate’s environmental life cycle (Aug 1 2022)
- Chocolate in all its delicious forms is one of the world’s favorite treats. Per capita consumption in the U.S. alone averages around 9 kilograms (19.8 pounds) per year. The industry is worth more than $90 billion globally.
- Ingredients — including cocoa, palm oil and soy — flow from producer nations in Africa, Asia and South America to processors and consumers everywhere. But a recent study reveals that large amounts of these commodities are linked to indirect supply chains, falling outside sustainability programs and linked to untraced deforestation.
- Key producers of these commodities — mostly West African countries for cocoa, Brazil for soy, and Indonesia for palm oil — have faced extensive deforestation due to agricultural production, and will likely face more in future as chocolate demand increases.
- Production, transport and consumption of chocolate also have their own environmental impacts, some of which remain relatively understudied. But researchers inside and outside the industry are working to better trace chocolate deforestation, and to make processing, shipping and packaging more sustainable.

Organized crime drives violence and deforestation in the Amazon, study shows (Aug 1 2022)
- Increasing rates of both deforestation and violence in the Brazilian Amazon are being driven by sprawling national and transnational criminal networks, a study shows.
- Experts say criminal organizations engaged in activities ranging from illegal logging to drug trafficking often threaten and attack environmentalists, Indigenous people, and enforcement agents who attempt to stop them.
- In 2020, the Brazilian Amazon had the highest murder rate in Brazil, at 29.6 homicides per 100,000 habitants, compared to the national average of 23.9, with the highest rates corresponding to municipalities suffering the most deforestation.
- Experts say the current government’s systematic dismantling of environmental protections and enforcement agencies has emboldened these criminal organizations, which have now become “well connected, well established and very strong.”

No permit? No problem for palm oil company still clearing forest in Papua (Aug 1 2022)
- A field observation by Greenpeace Indonesia has confirmed reports that a palm oil company has resumed clearing land on its concession in Indonesia’s Papua region despite its permit having been revoked.
- As of June, the company, PT Permata Nusa Mandiri (PNM), had cleared more than 100 hectares (247 acres) of land, according to data from Greenpeace Indonesia.
- The resumption of land clearing has prompted the district head to reprimand PNM, and raised the possibility that the company is committing a crime.

From agribusiness to oil to nuclear power and submarines: welcome to anti-environmental Putin-Bolsonaro alliance (commentary) (Aug 1 2022)
- Brazil’s dependence on Russian fertilizers has contributed to Jair Bolsonaro’s friendly relationship with Vladimir Putin as well as environmental impacts in the South American nation.
- In this editorial Nikolas Kozloff, an American academic, author and photojournalist, reviews some of the implications of the growing ties between the two leaders, including deforestation in the Amazon, extractive industries, and infrastructure projects.
- This article is a commentary. The views expressed are those of the author, not necessarily of Mongabay.

Deforestation intensifies in northern Malaysia’s most important water catchment (Jul 28 2022)
- The Ulu Muda rainforest is one of the last large, continuous tracts of forest in the Malay Peninsula, providing vital habitat for countless species as well as water for millions of people in northern Malaysia.
- Satellite data indicate deforestation activities are intensifying in the greater Ulu Muda landscape, including in protected areas such as Ulu Muda Forest Reserve.
- Sources say the forest loss is likely due to legal logging.
- Conservationists worry that the loss of Ulu Muda rainforest will have detrimental impacts on the region’s biodiversity and water security, as well as contribute to global climate change.

Indigenous Shuar community in Ecuador wins decades-long battle to protect land (Jul 28 2022)
- Ecuador’s National System of Protected Areas now includes the 5,497-hectare (13,583-acre) ancestral Tiwi Nunka Forest in the country’s south.
- The Shuar Indigenous community of El Kiim, with the help of the NGO Nature and Culture International, has been fighting for decades to protect the land from cattle ranchers, loggers and miners.
- National protections mean the land is safe from exploitation by mining companies, which sometimes find ways to bypass less stringent conservation protections.

Chimps digging wells shows learned behavior that may help amid climate change (Jul 28 2022)
- A recent study using camera traps and direct observation documented well-digging behavior in a group of chimpanzees in Uganda, initiated by a female that had immigrated into the group.
- Researchers were surprised to observe this behavior in this rainforest-dwelling population as water tends to be easily accessible in this habitat.
- The findings suggest this learned behavior may be helpful for the conservation of this group, as the chimps have picked up an adaptive measure that could help them survive a drought.

In Congo, a carbon sink like no other risks being carved up for oil (Jul 28 2022)
- New research has revealed that the peatlands of the Congo Basin are 15% larger than originally thought.
- This area of swampy forest holds an estimated 29 billion metric tons of carbon, which is the amount emitted globally through the burning of fossil fuels in three years.
- Beginning July 28, the government of the Democratic Republic of Congo, where two-thirds of these peatlands lie, will auction off the rights to explore for oil in 27 blocks across the country.
- Scientists and conservationists have criticized the move, which the government says is necessary to fund its operations. Opponents say the blocks overlap with parts of the peatlands, mature rainforest, protected areas, and a UNESCO World Heritage site.