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

Countering Bolsonaro’s UN speech, Greenpeace releases Amazon deforestation photos (21 Sep 2021 23:59:56 +0000)
- Hours after Brazilian President Jair Bolsonaro painted a rosy picture of his administration’s environmental record during a United Nations speech, Greenpeace and other environmental groups released a set of photos showing continued deforestation and fires in Earth’s largest rainforest.
- Speaking to the U.N. General Assembly in New York on Tuesday, Brazilian President Jair Bolsonaro cited a 32 percent reduction in deforestation in the month of August relative to a year ago, the country’s near decade-old Forest Code, and lands set aside as Indigenous territories — which he’s fought to undermine and dismantle — as evidence of Brazil’s contributions toward mitigating climate change.
- But activists pushed back on Bolsonaro’s statement, noting rising deforestation in the Amazon and his administration’s rollback of environmental laws and law enforcement, while publishing dramatic images captured in two Amazon states between September 14 and 17.
- Brazil does have some of the strongest forest protection laws on the books among major tropical forest nations, but enforcement has been lax, especially under Bolsonaro, when the deforestation rate in the Amazon has climbed to the highest level since 2008. Bolsonaro’s reference to one month of deforestation data doesn’t reflect the trend of rising deforestation that he’s presided over since taking office in January 2019.

Fires in the Amazon have already impacted 90% of plant and animal species (21 Sep 2021 16:23:22 +0000)
- New study addresses the effects of fires on biodiversity loss in the world’s largest forest during the last two decades.
- Researchers measured the impacts on the habitats of 14,000 species of plants and animals, finding that 93 to 95% suffered some consequence of the fires.
- Primates were the most affected, as they depend on trees for movement, food and shelter. Rare and endemic species with restricted habitats suffered the strongest impacts.
- The study assessed two decades of fires between 2001 and 2019 and confirmed the impact of environmental policies on deforestation cycles in the Amazon; law enforcement was concluded to have direct impact on the extent and volume of fires.

Extinction of Indigenous languages leads to loss of exclusive knowledge about medicinal plants (20 Sep 2021 16:25:54 +0000)
- A study at the University of Zurich in Switzerland shows that a large proportion of existing medicinal plant knowledge is linked to threatened Indigenous languages. In a regional study on the Amazon, New Guinea and North America, researchers concluded that 75% of medicinal plant uses are known in only one language.
- The study evaluated 645 plant species in the northwestern Amazon and their medicinal uses, according to the oral tradition of 37 languages. It found that 91% of this knowledge exists in a single language, and that the extinction of that language implies the loss of the medicinal knowledge as well.
- In Brazil, Indigenous schools hold an important role in preserving languages alongside cataloguing and revitalization projects like those held by the Karitiana people in Rondônia and the Pataxó in Bahia and Minas Gerais.

Scientists look to chimps’ past to gauge their future under climate change (17 Sep 2021 05:08:02 +0000)
- In a new study, scientists have uncovered where chimpanzees rode out periods of global change over the past 120,000 years, revealing insights into how they might be affected by future climate change.
- The team identified important long-term, resilient chimpanzee habitat in the Upper and Lower Guinean forests of West and Central Africa, and the Albertine Rift in East Africa that had been previously overlooked.
- The authors stress the vital role of understanding the past in predicting how future climate changes will affect wildlife abundance and distribution.

For Indonesian MPs, Indigenous rights may be bad for business, report says (17 Sep 2021 05:03:47 +0000)
- Indonesia’s Indigenous rights bill continues to languish in parliament because it threatens the business interests of lawmakers, activists say in a new report.
- The bill was submitted in 2012 to parliament, where nearly six out of every 10 lawmakers either owns or is involved in a business that could potentially be impacted if the land rights of Indigenous communities are recognized.
- The head of the parliamentary committee working on the bill has acknowledged lawmakers’ “paranoia” toward the legislation, saying parliament’s leaders have repeatedly refused to bring it to a floor vote.
- The inaction on the bill is in stark contrast to the rapid passage last year of two pro-business bills — one a slate of deregulatory measures, and the other an amended mining law — that will make it easier for companies and the government to seize Indigenous lands, among other points.

Illegal logging reaches Amazon’s untouched core, ‘terrifying’ research shows (15 Sep 2021 21:45:33 +0000)
- Satellite imagery shows that logging activity is spreading from peripheral areas of the Amazon toward the rainforest’s core, according to groundbreaking research.
- The satellite-based mapping of seven of Brazil’s nine Amazonian states showed a “terrifying” pattern of logging advance that cleared an area three times the size of the city of São Paulo between August 2019 and July 2020 alone.
- At the state level, lack of transparency in logging data makes it impossible to calculate how much of the timber production is illegal, experts say.
- Evidence of cutting in Indigenous reserves and conservation units — where logging is prohibited — make clear that illegal logging accounts for much of the activity, according to the report.

Myanmar’s snowcapped north is a haven for large mammals, new study finds (13 Sep 2021 12:03:13 +0000)
- A camera-trapping study has confirmed that the snowcapped Hkakaborazi landscape in northern Myanmar is a crucial haven for large mammals.
- The research team deployed 174 cameras in the forests and mountain slopes and interviewed local villagers, detecting 40 large mammal species overall.
- Species included evolutionarily distinct and globally endangered species, such as Chinese red pandas, dholes, Shortridge’s langurs and takins.
- The authors recommend a southern extension of a national park boundary to protect forests that are risk of being lost due to agricultural expansion and overhunting.

Deforestation sweeps national park in Brazil as land speculators advance (10 Sep 2021 23:56:11 +0000)
- Between January and early September, 3,542 deforestation alerts have been confirmed in primary forest within Campos Amazônicos National Park, according to satellite data, representing a 37% jump over the average amount of forest loss for the previous five years.
- Much of the occupation of the Campos Amazônicos park is happening through illegitimate land claims, fueled by hopes that protections on the park may be loosened in the future, environmentalists say. Even though the park is under federal protection, this hasn’t stopped invaders from falsely registering slices of it as their property.
- Environmentalists warn the social and environmental impacts could be devastating. Campos Amazônicos wraps around the Tenharim do Igarapé Preto Indigenous Reserve, which was until recently under attack by illegal miners who descended on the territory in search of cassiterite; sources say the fresh incursions into Campos Amazônicos could put the area back at risk.
- The park also holds one of the most striking enclaves of cerrado in the Amazon rainforest, housing stretches of shrubs, grasslands and dry forest typical of the savanna biome. Campos Amazônicos is also part of the Southern Amazon Conservation Corridor that represents one of the best-preserved stretches of the rainforest.

After surge, Amazon deforestation slows for second straight month (10 Sep 2021 17:04:38 +0000)
- Deforestation in the Brazilian Amazon declined for the second straight month according to data released today by Brazil’s national space research institute INPE.
- Year to date, INPE’s DETER deforestation alert system has registered 5,822 square kilometers of forest clearance. At this time last year the tally stood at 6,099 square kilometers.
- Deforestation in the Brazilian Amazon hit a 12-year high last year.

Indonesia terminates agreement with Norway on $1b REDD+ scheme (10 Sep 2021 14:36:39 +0000)
- The Indonesian government has decided to terminate a $1 billion deal with Norway under which Indonesia preserves its rainforests to curb carbon dioxide emissions.
- The Indonesian government says the decision is made after thorough consultations and cites lack of progress in the payment by Norway as one of the reasons for the termination.
- The Indonesian government says it remains committed to reduce greenhouse gas emissions despite ending the agreement.
- The Norwegian government says the two governments had been engaged in discussions on a legal agreement for the transfer of the payment, and the discussions were still ongoing and progressing well up until the announcement.

Indonesia lays out plan to rescue 15 lakes under pressure from human activity (10 Sep 2021 12:23:15 +0000)
- Indonesia has announced a plan to restore 15 deteriorating lakes across the country by 2024.
- The ecosystem of these lakes has been degraded largely by human-related activities, such as pollution, logging and destructive fishing practices.
- Observers have welcomed the new policy, saying the strategies outlined appear to address the threats faced by the lakes.
- These lakes are crucial in supporting the livelihoods of local communities as they serve as a source of freshwater, as flood control, and as sites for fish farming and tourism.

As illegal logging route in Peru nears Brazil, Indigenous groups warn of calamity (09 Sep 2021 14:37:16 +0000)
- Loggers are illegally reopening an abandoned road in Peru’s Ucayali region, threatening the dozens of Indigenous territories along the country’s border with Brazil, activists say.
- The UC-105 road reportedly cut through the Sawawo Indigenous Reserve in Peru last month, stopping just 11 kilometers (less than 7 miles) from the Brazilian border.
- The project is not authorized by Peru’s government but has forged ahead anyway, with no environmental impact studies or consultation with communities, Indigenous leaders say.
- Critics of the road say it will bring a surge in deforestation, drug trafficking and river degradation for the region’s Indigenous communities, who have been fighting off the loggers for decades and are now demanding authorities act to stop the advance of the road.

Environmental activist ‘well-hated’ by Myanmar junta is latest to be arrested (09 Sep 2021 09:41:45 +0000)
- As demonstrations and deadly crackdowns continue in Myanmar, land and environmental defenders are increasingly under threat.
- On Sept. 6, environmental and democracy activist Kyaw Minn Htut became one of the latest political prisoners; authorities had detained his wife and 2-year-old son a day earlier.
- He had openly challenged the military and reported on illegal environmental activities, making him a “well-known and well-hated” target, fellow activists said.
- Some 20 environmental organizations across the world have signed a statement calling for Kyaw Minn Htut’s release.

Fomenting a “Perfect Storm” to push companies to change: Q&A with Glenn Hurowitz (09 Sep 2021 08:50:35 +0000)
- Over the past few years, Mighty Earth has emerged as one of the most influential advocacy groups when it comes pushing companies to clean up their supply chains. The group, has targeted companies that produce, trade, and source deforestation-risk commodities like beef, palm oil, cocoa, rubber, and soy.
- Mighty Earth is led by Glenn Hurowitz, an activist who has spent the better part of the past 20 years advocating for forests and forest-dependent communities. In that capacity, Hurowitz has played a central role in pressing some of the world’s largest companies to adopt zero deforestation, peatlands, and exploitation (ZDPE) commitments.
- Mighty Earth’s strategy is built on what Hurowitz calls the “Perfect Storm” approach: “We work to bring pressure on a target from multiple different angles in a relatively compressed time period to the point that it becomes irresistible: their customers, financiers, media, grassroots, digital, direct engagement with the company,” he explained. “It’s an application of the basic principles of classical military strategy, combined with social change theory and a lot of hard-won experience to the field of environmental campaigning.
- Hurowitz spoke about how to drive change, the evolution of environmental activism, and a range of other topics during an August 2021 conversation with Mongabay founder Rhett A. Butler.

Borneo’s bearded pigs and traditional hunters adapted to oil palms. Then came swine fever (08 Sep 2021 13:46:06 +0000)
- Oil palm expansion and urbanization have altered the traditional hunting of bearded pigs by the Indigenous Kadazandusun-Murut (KDM) community in Sabah, Malaysia, a new study has found.
- Researchers interviewed 38 hunters on changes in pig behavior and hunting practices before the African swine fever (ASF) epidemic hit Sabah in 2021.
- They found that even though pig hunting patterns have changed dramatically, the activity remains a cornerstone of KDM communal culture for food, sport, gift-giving, festivals and celebrations.
- As ASF devastates wild pig populations, the researchers’ findings highlight a need for long-term hunting management that conserves both the bearded pig and Indigenous cultural traditions.