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

There’s still room to save Asia’s hoolock gibbons, study says, but only just (27 Jul 2021 16:18:19 +0000)
- Hoolock gibbon habitat has declined in the past few decades, but enough suitable patches exist today to guarantee the long-term survival of the genus if properly conserved.
- Particular populations are at greater risk of local extinction and should be translocated, including scattered western hoolock populations in Bangladesh.
- Researchers have also identified strongholds where a relatively high number of hoolock gibbons have been estimated, and which are currently highly threatened, to be prioritized for conservation.
- Hoolock gibbons are particularly vulnerable to forest fragmentation and degradation due to certain behavioral traits, which makes protecting large patches of habitat much more effective than conserving many small and fragmented areas.

Camera trap cameo for Buru Island babirusa last seen 26 years ago (27 Jul 2021 15:11:49 +0000)
- Camera traps have snapped the babirusa “deer-pig,” a type of tusked wild swine, on an island in Indonesia where they hadn’t been observed in more than a quarter of a century.
- Locals on Buru Island had previously reported seeing the animal there, but the new images are the first official confirmation of babirusa there since 1995.
- Officials are designing a conservation program for the Maluku or hairy babirusa (Babyrousa babyrussa) found on Buru and trying to determine its presence on two other islands.
- According to local lore, a babirusa will appear to guide a person lost in the forest to safety.

For an Indigenous group in Sumatra, a forest regained is being lost once more (27 Jul 2021 13:56:00 +0000)
- The Indigenous community of Pandumaan-Sipituhuta in Indonesia’s North Sumatra province have started replanting frankincense trees in their customary forest after a company had cleared the land to make way for a pulpwood plantation.
- The community has been in conflict with the company, PT Toba Pulp Lestari, since 2009, which has led to numerous clashes and criminal charges brought by the company against community members.
- The government finally granted recognition of the Indigenous group’s rights to its ancestral forest at the end of 2020.
- But the size of the customary forest had been slashed by more than half after the government earmarked some of the forest to be converted into large-scale agricultural plantations under the national food estate program.

Huge wildlife corridor in Belize sees progress, boosting hope for jaguars and more (commentary) (26 Jul 2021 17:05:44 +0000)
- Conservationists are working hard to create the Maya Forest Corridor, connecting the massive Belize Maya Forest in the country’s northwest with the Maya Mountains Massif network of protected areas in southern Belize.
- Frequented by tapirs, opossums, armadillos, agoutis, jaguars, and other big cat species, the network of reserves and corridors could prove to be critical conservation infrastructure for the region.
- A biologist who was just there shares news of some major land purchases and plans for wildlife underpasses for the Coastal Road, which is now in development along the corridor’s route.
- The views expressed are of the author, not necessarily Mongabay.

Nearly 1 million km2 of intact forests menaced by extractives, study finds (26 Jul 2021 16:21:33 +0000)
- A new report shows that 975,000 km2 (376,500 mi2) of virgin forest, about the size of Egypt, is threatened by mining and oil and gas extraction.
- About 11% of the planet’s intact forests lie within mining concessions and 8% inside oil and gas concessions.
- Their loss spells trouble for efforts to save endangered wildlife, tackle climate change and preserve Indigenous communities inhabiting these undisturbed lands.
- The overlap between concessions and intact forests was the greatest in Central Africa, especially in the Congo Basin, which has seen a surge in extractive activity in recent years.

Illegal deforestation intensifies along Brazilian highway as agribusiness hopes swell (23 Jul 2021 23:44:34 +0000)
- Highway BR-319 runs some 885 km (550 mi) from Rondonia’s capital of Porto Velho to Manaus, the Amazon’s largest city.
- Brazil’s president Jair Bolsonaro has pledged to pave the portion of BR-319 that runs through the southern part of the state of Amazonas to ease the transportation of timber — and, eventually, soy — out of the remote, densely forested region.
- Environmentalists and researchers say this has encouraged outsiders to illegally invade and deforest large areas of intact forest.
- Satellite data and imagery shows deforestation has increased along the southern portion of the road in 2021, including in and near protected areas.

Global restoration now has an online meeting point (23 Jul 2021 18:35:59 +0000)
- Restor is a map-based, open-source platform created so that people can better plan, manage and monitor restoration projects. The locations of more than 50,000 restoration and conservation initiatives are now registered on the platform.
- On the platform, Restor users can view high-resolution satellite imagery of places around the globe to learn about their potential for restoration or conservation. It also allows users to see what tree species are native to a particular location.
- Currently, Restor is collecting data from restoration projects around the world. Anyone with a project can apply for access to the site where they are able to enter data about their project and ecosystem.
- Restor CEO Clara Rowe says they hope to “enable and accelerate ecological restoration … around the globe by making it easy for anyone, anywhere to engage.”

Lessons from the 2021 Amazon flood (commentary) (23 Jul 2021 16:25:38 +0000)
- In June 2021, the annual flood season in the western and central Amazon reached record levels, and dramatic scenes of inundated homes, crops and city streets captured attention beyond Amazonia. This event provides lessons that must be learned.
- The high flood waters are explained by climatological forces that are expected to strengthen with projected global warming. Damaging floods represent just one of the predicted impacts in Amazônia under a warming climate.
- The administration of Brazilian President Jair Bolsonaro must change its current denialist positions on global warming and its policies that encourage deforestation. The Amazon forest must be maintained for many reasons in addition to its role in avoiding climate change.
- This post is a commentary. The views expressed are those of the author, not necessarily Mongabay.

Better logging regulations ‘last best hope’ for Solomon Islands, study says (23 Jul 2021 07:55:09 +0000)
- Kolombangara is one of more than 900 islands that make up the Solomon Islands, where timber is a major export and logging continues at 19 times the sustainable rate.
- The island’s lowland forests have been intensively harvested since the mid-1960s; only the steep forests above 400 meters (1,300 feet) remain largely intact.
- If forests do not have enough time to recover between bouts of logging, scientists say, there will be cascading consequences for timber resources, biodiversity and ecosystem services on which local communities depend.
- They’re calling for improved national forest management policies that regulate reentry logging and incorporate land-use planning; conservation partners are also seeking formal protection of the island’s customary upland natural forests and investigating forest restoration techniques.

EU sanctions no ‘silver bullet’ against Myanmar’s illegal timber trade, experts say (22 Jul 2021 15:57:10 +0000)
- The European Union has imposed sanctions on Myanma Timber Enterprise, a state-owned entity that regulates all harvesting and sales of Myanmar timber.
- The new sanctions mean it is now illegal for businesses in the EU to directly import any timber from Myanmar.
- While the sanctions send a strong political signal to the junta, experts say their actual impact on Myanmar’s illegal timber trade could be limited.
- Local activists are urging the international community to do more as globally significant tracts of forests in the country come under threat, with illicit logging financing the military’s repressive rule.

Amazon and Cerrado deforestation, warming spark record drought in urban Brazil (22 Jul 2021 14:36:56 +0000)
- Southern and central Brazil are in the midst of the worst drought in nearly 100 years, with agribusiness exports of coffee and sugar, and the production of hydroelectric power, at grave risk.
- According to researchers, the drought, now in its second year, likely has two main causes: climate change, which tends to make continental interiors both hotter and drier, and the deforestation of the Amazon rainforest and Cerrado savanna biomes.
- Deforestation has caused the loss of almost half of the Cerrado’s native vegetation, which helps hold vast amounts of water underground, maintaining aquifers that supply the nation’s rivers with water. In the Amazon, rainforest loss is preventing billions of tons of water vapor from reaching the atmosphere.
- President Jair Bolsonaro acknowledges neither climate change nor deforestation as sources of the drought, but attributes it instead to the country and himself being “unlucky.” The administration’s drought response so far is to reactivate fossil-fuel power plants, which pollute heavily and are costly to operate.

Planned Brazil-Peru highway threatens one of Earth’s most biodiverse places (22 Jul 2021 11:54:03 +0000)
- Serra do Divisor National Park on Brazil’s border with Peru is home to numerous endemic animals and more than a thousand plant species, but faces a double threat from a planned highway and a bid to downgrade its protected status.
- The downgrade from national park to “environmental protection area” would paradoxically open up this Andean-Amazon transition region to deforestation, cattle ranching, and mining — activities that are currently prohibited in the park.
- The highway project, meant to give Acre another land route to the Pacific via Peru, has been embraced by the government of President Jair Bolsonaro, which has already taken the first steps toward its construction.
- Indigenous and river community leaders say they have not been consulted about the highway, as required by law, and have not been told about the proposed downgrade of the park, both of which they warn will have negative socioenvironmental impacts.

As soy frenzy grips Brazil, deforestation closes in on Indigenous lands (21 Jul 2021 22:38:09 +0000)
- A large swath of rainforest has been cleared and was burned on the edge of the Wawi Indigenous Territory in the Brazilian Amazon.
- The fire is one of many being set to clear land for soy cultivation, much of it legally mandated, as demand for the crop sees growers push deeper into the rainforest and even into Indigenous and protected areas.
- Enforcement against forest destruction has been undermined at the federal level, thanks to budget cuts and loosened restrictions by the administration of President Jair Bolsonaro.
- The burning threatens to compound health problems in Indigenous communities amid the COVID-19 pandemic, while the use of agrochemicals on the soy plantations poses longer-term hazards.

Protected areas keep adjacent lands safe, but face losing their own protection (21 Jul 2021 16:20:03 +0000)
- Safeguarding nature in one area can displace harmful activities, such as illegal logging or mining, into another, a phenomenon known as leakage or spillover; but how big is the problem?
- The first systematic review of studies examining the effects of protected areas around the globe on their surrounding areas found that less than 12% showed evidence of leakage or spillover, while the majority (54%) reduced deforestation in surrounding areas.
- Another study found that protected areas in the Brazilian Amazon overwhelmingly blocked deforestation in the surrounding forest, again suggesting that protected areas inhibit deforestation both within and outside of their boundaries.
- Experts say environmental and regulatory rollbacks that loosen restrictions on land use, shrink boundaries, or altogether eliminate protections pose a much greater threat to the Amazon than leakage, and efforts should focus on keeping protected areas permanent and improving management and enforcement of regulations.

Indonesia eyes less severe fire season, but COVID-19 could turn it deadly (20 Jul 2021 13:33:21 +0000)
- This year’s forest fire season in Indonesia is expected to be less severe than in previous years, but the haze from the burning could still compound the coronavirus crisis in the country.
- Favorable weather conditions and ongoing efforts to restore peatlands point to a “relatively benign” fire season, and hence less risk of severe haze, a new report says.
- Even before the pandemic, haze from forest and peat fires was known to increase cases of respiratory infections fourfold in the hardest-hit areas; combined with COVID-19, haze this time around could stretch the country’s overwhelmed hospitals beyond breaking point.
- Indonesia has recently become the global epicenter of the disease, registering more daily cases than India and Brazil, with the country’s doctors’ association warning the health care system has “functionally collapsed.”