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RAINFORESTS

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



RAINFOREST INFORMATION



Preface
World Rainforests
Rainforest Structure
Rainforest Biodiversity
Canopy
Forest Floor
Rainforest Waters
Indigenous People
Deforestation
Global Importance
Rainforest Conservation

References
Deforestation Charts
Deforestation Tables
Amazon Rainforest
Congo Rainforest
Deforestation in Brazil
Rainforest Images
FAQs
Interview with mongabay
Interviews with scientists
Other languages


RAINFOREST INFORMATION FOR KIDS



About rainforests
Rainforest animals
Rainforest people
In the rainforest

Why are rainforests important?
Why are rainforests disappearing?
How can we save rainforests?
Teaching resources



BACKGROUND INFORMATION ON RAINFORESTS



Rainforests
RAINFOREST FACTS

  • Tropical forests presently cover about 2.4 billion hectares or about 16 percent of Earth's land surface.
  • The world's largest rainforest is the Amazon rainforest
  • Brazil has the largest extent of rainforest cover
  • Rainforests also exist outside the tropics, including temperate North America, South America, Australia, and Russia.
  • An estimated 50 percent of terrestrial biodiversity is found in rainforests
  • Rainforests are thought to store at least 250 billion tons of carbon
  • Deforestation and degradation of tropical forests account for roughly 10 percent of global greenhouse emissions from human activities
  • 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.


    Global forest cover

    Data from
    FAO 2011.

    Data from
    Saatchi et al 2011.


    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, etc), appendices, and other resources.

    There is also a version of the site geared toward younger readers at kids.mongabay.com


    World rainforest map

    ABOUT RAINFORESTS (SUMMARY)


    Chapter 1: 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.

    Dozens of countries have tropical forests. The countries with the largest areas of tropical forest are (in order):
    • Brazil
    • Democratic Republic of Congo
    • Indonesia
    • Peru
    • Colombia
    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.

    rainforest cover by country

    Chapter 2: 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.

    Chapter 3: 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.

    There are several reasons why rainforests are so diverse. Some important factors are:
    • Climate: because rainforests are located in tropical regions, they receive a lot of sunlight. The sunlight is converted to energy by plants through the process of photosynthesis. Since there is a lot of sunlight, there is a lot of energy in the rainforest. This energy is stored in plant vegetation, which is eaten by animals. The abundance of energy supports an abundance of plant and animal species.
    • Canopy: the canopy structure of the rainforest provides an abundance of places for plants to grow and animals to live. The canopy offers sources of food, shelter, and hiding places, providing for interaction between different species. For example, there are plants in the canopy called bromeliads that store water in their leaves. Frogs and other animals use these pockets of water for hunting and laying their eggs.
    • Competition: while there is lots of energy in the rainforest system, life is not easy for most species that inhabit the biome. In fact, the rainforest is an intensively competitive place, with species developing incredible strategies and innovations to survive, encouraging specialization.
    While species everywhere are known for utilizing symbiotic relationships with other species to survive, the biological phenomenon is particularly abundant in rainforests.

    Chapter 4: The rainforest canopy

    Diagram showing the rainforest canopy structure
    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 outfitted with special sensors — conservation drones — to study the canopy.

    Chapter 5: 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.

    Chapter 6: Rainforest waters

    Map of the Amazon River Basin
    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.

    Chapter 7: 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.

    Chapter 8: Deforestation

    Every year an area of rainforest the size of New Jersey is cut down and destroyed, mostly the result of human activities. We are cutting down rainforests for many reasons, including:

  • wood for both timber and making fires;
  • agriculture for both small and large farms;
  • land for poor farmers who don’t have anywhere else to live;
  • grazing land for cattle (the single biggest driver of deforestation in the Amazon);
  • plantations, including wood-pulp for making paper, oil palm for making palm oil, and rubber;
  • road construction; and
  • extraction of minerals and energy.

    2012 data from Harris et al.
    Share of gross forest loss in tropical countries
    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.

    Chart: Forest loss across biomes

    Chapter 9: 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.
    Chapter 10: 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.


    RAINFOREST NEWS



    The largest biosphere reserve in Southeast Asia: Vietnam’s success story or a conservation failure? PART I
    (09/30/2014) In 2010, poachers shot and killed the last Javan rhino in Vietnam, wiping out an entire subspecies. The Sumatran rhino, the Malayan tapir and the civet otter, too, have disappeared from the country. Moreover, charismatic species like tigers, elephants, gibbons and the secretive saola discovered recently in Vietnam’s forests are at risk of extinction in the coming decades as threats to wildlife continue unabated in the country.


    Studying common birds could help save rare species in Vietnam
    (09/30/2014) Studies in conservation biology often focus on rare, threatened species faced with impending extinction, but what about common animals of least concern? Could they too help conservationists fine-tune their approach? Doctoral researcher Laurel Yohe not only claims that they can, but demonstrates how in a new study. She and five other researchers compared ranges of five babblers with development across Vietnam.


    Malaysian palm oil company destroys Borneo forests, despite buyer's zero deforestation commitment
    (09/30/2014) Malaysian palm oil company Genting Plantations is continuing to destroy forests despite a high-profile pledge by one of its customers to eliminate deforestation from its supply chain, alleges a report published by Greenomics, an Indonesian environmental group.


    A weed by any other name: remnant shrubs and trees play vital role in regenerating forests
    (09/29/2014) Tropical forest restoration projects are exciting research sites for scientists studying factors that affect ecosystem recovery. Here, scientists are trying to understand plant community succession, i.e. the process of recovery after cleared lands are abandoned and allowed to regrow naturally. One of the most important components of this recovery process is seed dispersal, since seeds from nearby forests allow a deforested habitat to become populated again by native plants and trees.


    Climate change to boost farmland, diminish harvests, says new study
    (09/29/2014) Climate change is likely to alter how we humans grow adequate amounts of food for a swelling global population. Assessing just how much and where those changes will occur has been difficult. But a new study takes aim at those very questions and could provide a guide for the debate over feeding the planet while also preserving biodiversity and the forests that filter out the carbon we produce.


    Diverse, deceptive, declining: orchids threatened by deforestation in South America
    (09/26/2014) Pushing past a thick fern leaf, Crain stopped short, overcome by joy. As he broke into dance, his assistant peered curiously at the tiny lentil-shaped fruit dangling from a stem, and resolutely decided Crain was mad. After more than two years studying a rare Puerto Rican endemic orchid species, Crain had finally found his first specimen bearing fruit.


    Reintroduction program ups Mexico's scarlet macaw population by 34 percent in one year
    (09/25/2014) While listed as Least Concern by the IUCN, the scarlet macaw has disappeared from almost all of its native range in Mexico, is very rare in most Central America countries, and is locally extinct in El Salvador. A new paper published this week finds a reintroduction program was hugely successful in its first year of operation, with a 92 percent survival rate for released birds.


    Four countries pledge to restore 30 million hectares of degraded lands at UN Summit
    (09/25/2014) In 2011, Germany and the International Union for the Conservation of Nature launched the Bonn Challenge, which pledged to restore 150 million hectares of degraded and deforested lands by 2020. Several countries have already made commitments—including the U.S.—but this week at the UN Climate Summit four more jumped on board.


    Scientists uncover six potentially new species in Peru, including bizarre aquatic mammal (photos)
    (09/25/2014) A group of Peruvian and Mexican scientists say they have uncovered at least six new species near South America's most famous archaeological site: Machu Picchu. The discoveries include a new mammal, a new lizard, and four new frogs. While the scientists are working on formally describing the species, they have released photos and a few tantalizing details about the new discoveries.


    In the shadows of Machu Picchu, scientists find 'extinct' cat-sized mammal
    (09/25/2014) Below one of the most famous archaeological sites in the world, scientists have made a remarkable discovery: a living cat-sized mammal that, until now, was only known from bones. The Machu Picchu arboreal chinchilla rat (Cuscomys oblativa) was first described from two enigmatic skulls discovered in Incan pottery sculpted 400 years ago.


    Turning point for Peru's forests? Norway and Germany put muscle and money behind ambitious agreement
    (09/24/2014) From the Andes to the Amazon, Peru houses some of the world's most spectacular forests. Proud and culturally-diverse indigenous tribes inhabit the interiors of the Peruvian Amazon, including some that have chosen little contact with the outside world. And even as scientists have identified tens-of-thousands of species that make their homes from the leaf litter to the canopy.


    Scientists use genes, feces to study disappearing monkeys
    (09/24/2014) Human pressures through tree clearing and poaching are reducing both forest and fauna in West Africa. In response to dwindling primate populations, scientists used genetics techniques to examine their makeup and outlook – demonstrating the usefulness of such methods in the study of animals that are becoming ever-fewer in number and ever-harder to find.


    More rainforest news




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    RAINFOREST PICTURES


    Imbak Canyon Conservation Area
    Red-eyed tree frog
    Male panther chameleon (Furcifer pardalis)
    Strangler fig
    Rainforest of the Darien
    Forest elephant in Gabon
    Mother tarsier and baby
    Knobbed hornbill
    Central American Agouti eating a fallen fruit<br>(pan02-1824)
    Panamanian Three-toed Sloth (Bradypus variegatus)<br>(pan02-2095)
    Borugo (Agouti taczanowskii)
    Jaguar (Panthera onca)
    Borneo rainforest in Malaysia
    Clipper butterfly (Parthenos sylvia)
    Pristine rainforest in Imbak Canyon, Malaysia
    Scale-crested Pygmy-tyrant (Lophotriccus pileatus)
    Madagascar Tomato Frog (Dyscophus antongilii)
    Transparent moth, Costa Rica
    Canopy of the Osa Peninsula rainforest
    Looking up the trunk of a rainforest tree
    Rainforest in West Kalimantan
    Baby gorilla (Gorilla gorilla), Gabon
    Rainforest canopy seen from the base of a compass tree
    River valley on the Amazon side of the lower Andes
    Buttress roots of a rainforest tree on Peucang Island
    Emerald eyes frog (Hypsiboas crepitans)
    Monkey frog (Phyllomedusa bicolor)
    Blue arrow poison frog
    Rainforest in Borneo
    Red passion vine flower
    Jungle lowland rainforest reaching the coast of New Guinea
    Bennett's blue weevil (Eupholus bennetti - Curculionidae family), a spectacular blue and turquoise beetle from New Guinea
    Cock of the rock in Peru
    Waterfall in Bwindi
    River valley in the Arfak mountains
    Rain forest giant
    Mantadia rainforest
    Danum river in Borneo
    Male Sumatran orangutan, Indonesia
    Tree Runner lizard (Plica plica)

    [Slideshow view]


    RAINFORESTS
    By Rhett A. Butler

    An overview of tropical rainforests for kids, based on mongabay.com's popular web site for children (kids.mongabay.com). Rainforests describes tropical rainforests, why they are important, and what is happening to them.

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    Some books

  • One River Wade Davis
  • Nature of the Rainforest: Costa Rica and Beyond Adrian Forsyth at al.
  • Tropical Nature: Life and Death in the Rain Forests of Central and South America Adrian Forsyth & Ken Miyata
  • Don't Sleep, There Are Snakes: Life and Language in the Amazonian Jungle Daniel L. Everett
  • Medicine Quest: In Search of Nature's Healing Secrets Mark J. Plotkin
  • 1491: New Revelations of the Americas Before Columbus Charles C. Mann



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