The Registry Of Nature Habitats

The map below shows the location of the world's tropical rainforests. Rainforests cover only a small part of the earth's surface - about 6%, yet they are home to over half the species of plants and animals in the world.

CENTRAL AMERICA: This region was once entirely covered with rainforest, but large areas have been cleared for cattle ranching and for sugar cane plantations. Like other major rainforests, the jungles and mangrove swamps of Central America contain many plants and animals found nowhere else. Central America is famous for its large number of tropical birds, including many kinds of parrots.

THE AMAZON: The Amazon jungle is the world's largest tropical rainforest. The forest covers the basin of the Amazon, the world's second longest river.The Amazon is home to the greatest variety of plants and animals on Earth. A 1/5 of all the world's plants and birds and about 1/10 of all mammal species are found there.

AFRICA: Central Africa holds the world's second largest rainforest. To the south east, the large island of Madagascar was once intensively forested, but now much of it is gone. Africa contains areas of high cloud forest, mangrove swamps and flooded forests. The island of Madagascar is home to many unique plants and animals not found anywhere else.

SOUTHERN ASIA: The rainforests of Asia stretch from India and Burma in the west to Malaysia and the islands of Java and Borneo in the east. Bangladesh has the largest area of mangrove forests in the world. In Southeast Asia the climate is hot and humid all year round. In the mainland Asia it has a subtropical climate with torrential monsoon rains followed by a drier period.

AUSTRALASIA: Millions of years ago, Australia, New Zealand and the island of New Guinea formed part of a great forested southern continent, isolated from the rest of the world. Today these countries contain many different species of animal that occur nowhere else.Undergrowth in Australia's tropical forests is dense and lush. The forests lie in the path of wet winds blowing in from the Pacific.

Tropical rainforests are the most diverse ecosystem on Earth, and also the oldest. Today, tropical rainforests cover only 6 percent of the Earth's ground surface, but they are home to over half of the planet's plant and animal species. In this completely unique world, there are thousands of species we have yet to discover.

Generally speaking, a rainforest is an environment that receives high rainfall and is dominated by tall trees. A wide range of ecosystems fall into this category, of course, including the old-growth temperate forests of the Pacific Northwest. But most of the time when people talk about rainforests, they mean the tropical rainforests located near the equator.

These forests, concentrated in Africa, Australia, Asia, and Central and South America, receive between 160 and 400 inches (406.4 to 1016 cm) of rain per year. Unlike the rainforests farther to the north and south, tropical rainforests don't really have a "dry season." In fact, they don't have distinct seasons at all. The total annual rainfall is spread pretty evenly throughout the year, and the temperature rarely dips below 60 degrees Fahrenheit (16 degrees Celsius).

This steady climate is due to the position of rainforests on the globe. Because of the orientation of the Earth's axis, the Northern and Southern hemispheres each spend part of the year tilted away from the sun. Since rainforests are at the middle of the globe, located near the equator, they are not especially affected by this change. They receive nearly the same amount of sunlight, and therefore heat, all year. Consequently, the weather in these regions remains fairly constant.

The consistently wet, warm weather and ample sunlight give plant life everything it needs to thrive. Trees have the resources to grow to tremendous heights, and they live for hundreds, even thousands, of years. These giants, which reach 60 to 150 ft (18 to 46 m) in the air, form the basic structure of the rainforest. Their top branches spread wide in order to capture maximum sunlight. This creates a thick canopy level at the top of the forest, with thinner greenery levels underneath. Some large trees, called emergents, grow so tall (up to 250 ft / 76 m) that they even tower over the canopy layer.

As you go lower, down into the rainforest, you find less and less greenery. The forest floor is made up of moss, fungi, and decaying plant matter that has fallen from the upper layers. The reason for this decrease in greenery is very simple: The overabundance of plants gathering sunlight at the top of the forest blocks most sunlight from reaching the bottom of the forest. The lowest levels of the rainforest are extremely dark, making it difficult for robust plants to thrive. As little as 1 percent of the light shining onto the forest reaches the lowest levels.

This makes for a fascinating biological community in which plant life is striving to reach 100 ft (30.5 m) into the air, and most food for animals comes from above.

There are over 3,000 fruits found in rainforests. People in the Western World make use of about 200 of them, but the indigenous tribes of the rainforest make use of over 2,000. Roughly 80 percent of the food we eat originally came from tropical rainforests. Without rainforests, we wouldn't have the seeds that produce coffee and chocolate. Other rainforest foods include tomatoes, potatoes, rice, bananas, black pepper, pineapples and corn. Rainforest tribes also have a knowledge of rainforest medicine that far exceeds the Western World's. One major problem with deforestation is the devastating effect it has on these tribes. As these cultures are lost, so is their extensive knowledge of the vast resources of the rainforest, whose wild plants are vital to our well being. The ample sunlight and extremely wet climate of many tropical areas encourages the growth of towering trees with wide canopies. This thick top layer of the rainforest dictates the lives of all other plants in the forest. New tree seedlings rarely survive to make it to the top unless some older trees die, creating a "hole" in the canopy. When this happens, all of the seedlings on the ground level compete intensely to reach the sunlight. Most other plants survive by taking advantage of the trees that form the canopy layer.

Many plant species reach the top of the forest by climbing the tall trees. It is much easier to ascend this way, because the plant doesn't have to form its own supporting structure. Lianas, long, woody plants that can grow more than 8 inches (20 cm) across, will often climb tall trees all the way up to the canopy layer. At the top of the forest, these climbers may spread from tree to tree, making the canopy ceiling even thicker. Some plant species, called epiphytes, grow directly on the surface of the giant trees. These plants, which include a variety of orchids and ferns, make up much of the understory, the layer of the rainforest right below the canopy. Epiphytes are close enough to the top to receive adequate light, and the runoff from the canopy layer provides all the water and nutrients they need, which is important since they don't have access to the nutrients in the ground. Some epiphytes eventually develop into stranglers. They grow long, thick roots that extend down the tree trunk into the ground. As they continue to grow, the roots form a sort of web structure all around the tree. At the same time, the strangler plant's branches extend upward, spreading out into the canopy. Eventually, the strangler may block so much light from above, and absorb such a high percentage of nutrients from the ground below, that the host tree dies. When the host decomposes, the strangler's lattice of roots remains, giving the plant the structure it needs to reach from the forest floor to the canopy.

Competition over nutrients is almost as intense as competition for light. The excessive rainfall rapidly dissolves nutrients in the soil, making it relatively infertile except at the top layers. For this reason, rainforest tree roots grow outward to cover a wider area, rather than downward to lower levels. This makes rainforest trees somewhat unstable, since they don't have very strong anchors in the ground. Some trees compensate for this by growing natural buttresses. These buttresses are basically tree trunks that extend out from the side of the tree and down to the ground, giving the tree additional support.

Rainforest trees are dependent on bacteria that are continually producing nutrients in the ground. Rainforest bacteria and trees have a very close, symbiotic relationship. The trees provide the bacteria with food, in the form of fallen leaves and other material, and the bacteria break this material down into the nutrients that the trees need to survive. Even with this amazing symbiotic cycle, nutrients are scarce. Some plant species gather additional nutrients by capturing bugs or catching plant material that falls from the canopy above.

One of the most remarkable things about rainforest plant life is its diversity. The temperate rainforests of the Pacific Northwest are mainly composed of a dozen or so tree species. A tropical rainforest, on the other hand, might have 300 distinct tree species. This plant life is spread out over wide areas -- in a square acre, an entire species might be represented by only a few individual plants. Rainforests are home to the majority of animal species in the world. And a great number of species who now live in other environments, including humans, originally inhabited the rainforests. Researchers estimate that in a large rainforest area, there may be more than 10-million different animal species. Most of these species have adapted for life in the upper levels of the rainforest, where food is most plentiful. Insects, which can easily climb or fly from tree to tree, make up the largest group (ants are the most abundant animal in the rainforest). Insect species have a highly symbiotic relationship with the plant life in a rainforest. The insects move from plant to plant, enjoying the wealth of food provided there. As they travel, the insects may pick up the plants' seeds, dropping them some distance away. This helps to disperse the population of the plant species over a larger area -- underneath the canopy, the wind is not strong enough to carry seeds a significant distance, so plants depend entirely on animals for seed dispersal. Less-harmful insects may also help a plant by fighting off more destructive insect species. The numerous birds of the rainforest also play a major part in seed dispersal. When they eat fruit from a plant, the seeds pass through their digestive system. By the time they excrete the seeds, the birds may have flown many miles away from the fruit-bearing tree.

Most people are familiar with the colorful parrots of the tropical rainforests, but this is only one part of the total bird population. Rainforest bird species come in all shapes and sizes, from tiny hummingbirds to large toucans. Over one-fourth of all bird species in the world today live in tropical rainforests. There are also a large number of reptiles and mammals in the rainforest. Many of these species have remarkable adaptations for life in the trees. Some animals have very thin webs of skin that let them glide from branch to branch. Many mammals, including a wide variety of monkeys, have developed prehensile tails. Essentially, the tail works like an extra hand to grasp hold of tree branches. Obviously, this adaptation makes life much easier for animals who spend their lives in the trees. For example, a monkey might grab onto a branch with its tail so it can reach down to grab a piece of fruit that would otherwise be inaccessible.

Since the weather is so hot and humid during the day, most rainforest mammals are active only at night, dusk or dawn. The many rainforest bat species are especially well adapted for this lifestyle. Using their sonar, bats navigate easily through the mass of trees in the rainforest, feeding on insects and fruit. While most rainforest species spend their lives in the trees, there is also a lot of life on the forest floor. Great apes, such as gorillas and orangutans, wild pigs, big cats and even elephants can all be found in rainforests. There are a number of people who live in the rainforests, as well. These indigenous tribes -- which, up until recently, numbered in the thousands -- are being forced out of the rainforests at an alarming rate because of deforestation.

In the past hundred years, humans have begun destroying rainforests at an alarming rate. Today, roughly 1.5 acres of rainforest are destroyed every second. People are cutting down the rainforests in pursuit of three major resources:

In the past, scientists often referred to tropical rainforests as the "lungs of the world" because of the large amount of oxygen they produce. More recent evidence shows that rainforests don't have much of an effect on the world's oxygen supply. The decomposition of dead plant matter consumes roughly the same amount of oxygen that the living plants produce. But rainforests do play a key role in the global ecosystem. Some experts are now calling them the "air conditioners to the world," because their dark depths absorb heat from the sun. Without the forest cover, these regions would reflect more heat into the atmosphere, warming the rest of the world. Losing the rainforests may also have a profound effect on global wind and rainfall patterns, potentially causing droughts throughout the United States and other areas.

The act of deforestation itself affects the environment as a whole. Roughly 30 percent of the carbon dioxide released in the air (a leading cause of global warming) comes from burning the rainforests. In the current economy, people obviously have a need for all of these resources. But almost all experts agree that, over time, we will suffer much more from the destruction of the rainforests than we will benefit. There are several factors involved in this scientific assessment:

Fewer than 1 percent of rainforest plants have been examined for their medicinal properties. It is extremely likely that our best shot at curing cancer, AIDS and many other debilitating diseases lies somewhere in the world's diminishing rainforests. With some 137 rainforest species disappearing every day (the most rapid extinction rate in the history of the world), there's a good chance that we're losing valuable medicines by the minute.

There are approximately 2,000 million hectares of tropical forests in the world. They represent an enormously valuable resource in terms of the diverse economic products and environmental services they provide. At the present time, 14 to 16 million hectares of tropical forests are being converted each year to other land uses, mostly agricultural. The principal agents of deforestation -- those individuals who are cutting down the forests -- include slash-and-burn farmers, commercial farmers, ranchers, loggers, firewood collectors, infrastructure developers and others. The predisposing conditions that favour deforestation include poverty, greed, quest for power, population growth, and illiteracy. The indirect causes of deforestation include inappropriate government policies, land hunger, national and global market forces, the undervaluation of natural forests, weak government institutions, and social factors. The more visible direct causes of deforestation include the land uses that compete with the natural forests (e.g. agriculture, ranching, infrastructure development, and mining and petroleum exploration). Logging, fuelwood collection, and tree plantations also have a role in the deforestation phenomena. The economic and environmental consequences of deforestation are profound, making it one of the most critical issues facing our global society. While it is impossible to stop deforestation in the foreseeable future, there are many opportunities for bringing it under control and minimizing its negative impacts. Alternatives include the protection and management of remaining forests, socioeconomic development in rural areas, and policy and institutional reforms.

The world's rainforest are an extremely valuable natural resource, to be sure, but not for their lumber or their land. They are the main cradle of life on Earth, and they hold millions of unique life forms that we have yet to discover. Destroying the rainforests is comparable to destroying an unknown planet -- we have no idea what we're losing. If deforestation continues at its current rate, the world's tropical rainforests will be wiped out within 40 years.

DEFORESTATION - PAST AND PRESENT

Historical Deforestation

Rain Forest Deforestation

Eight thousand years ago at the advent of sedentary agriculture, forests covered approximately 40 per cent of the world's land area or about 6,000 million hectares. For the next 7,500 years, farm and pasture lands gradually crept into the forests, covering the most fertile, most accessible soils. The areas most greatly affected were the Middle East, the Mediterranean watershed, South Asia, and the Far East. Forest removal in Mesopotamia and the Mediterranean Basin was well advanced in pre-Christian times. Those forests that do remain are in many cases badly degraded. For example, in Turkey, the forests of Pinus brutia have been selectively harvested for only the tallest, the straightest trees for centuries. The present trees are now reported to be genetically inferior in form and stature, a consequence of harvesting only the best trees. In centuries past, countries like China and India had considerably more forest cover than they do today. Their forests were decimated to supply their growing populations with wood for building materials, to provide firewood to cook their food and heat their houses, and to open up new lands to grow crops on.

After the first European contact with the New World over 500 years ago, the forests of the Western Hemisphere also began to disappear. The more accessible forests of coastal Brazil and those of the Caribbean were converted into sugar plantations. In North America, settlers arrived from Europe and slaves were brought in from Africa to convert what was once a vast expanse of temperate forest into farms and ranches. Forests were cleared to accommodate the settlers' growing needs for new land on which to grow their food crops. Favourable temperate soils made sustainable agriculture possible and a viable alternative to forestry as the best use of the land. Forests were also cleared for firewood for cooking and heating, and for construction wood for houses and furniture. Meanwhile, back in Europe, the arrival of the Industrial Revolution put tremendous pressure on the remaining forests to supply fuel for the smelters and foundries of the new industries. Before the end of the 19th century, most of the Europe's ancient forests were only distant memories. Between 1850 and 1980, 15 per cent of the world's forests and woodlands were cleared. The world forest area has now shrunk to 3,500 million hectares as a consequence of human exploitation, most of which occurred in the latter half of the 20th century.

Contemporary Deforestation

Rain Forest Contemporary Deforestation

Although the world's forest area has been declining for centuries, it is in the last half of the 20th century that the process has accelerated to alarming proportions. Since the 1960s there has been a major change in the rate at which tropical forests are being cleared. In contrast, the area of temperate forests in developed countries grew by 0.1 per cent in the 1980s. For example, Canada witnessed a net increase in its area of forest land from 416.2 million hectares in the late 1980s to 417.6 million hectares in 1997 -- an increase of 1.4 million hectares.

How much forest is being lost to deforestation? The Food and Agriculture Organization of the United Nations (FAO 1997) has estimated the annual rates of deforestation in developing countries at 15.5 million hectares for the period 1980-1990 and 13.7 million hectares for 1990-1995. The total forest area lost during the 15 year period was approximately 200 million hectares. To put this figure in perspective, 200 million hectares is more than the total land area of Mexico or Indonesia.

FAO reports that the change in forest cover between 1980 and 1990 in Africa is largely the result of the forests being cleared for small farmer agriculture and permanent agriculture/pastures, with slow, progressive degradation occurring from firewood collection. Rural population pressures were attributed to be the main driving force behind these changes. In contrast, Latin America has seen a shift towards permanent agriculture and cattle ranching, often in association with settlement and infrastructure projects. In Asia, the situation is more complex with large resettlement schemes, intensive timber harvesting, the expansion of commercial agriculture, and the continued spread of shifting cultivation into the remaining forests. Converting forests to plantations, both forest plantations and agriculture plantations (e.g. rubber, oil palm,) was carried out on a large scale in Asia. The tragedy lies in the fact that most of these deforested lands are not suited for long-term farming or grazing and they quickly degrade once the forest has been cut and burnt. In fact, throughout the tropics, very few of the forested lands that are left have any potential for sustainable agriculture.

Desertification, particularly in Africa and Asia, has also contributed to deforestation through land degradation in drier climates. It affects about 3,000 to 3,500 million hectares, about one-quarter of the world's land area as a consequence of unsustainable over-cultivation, over-grazing, over-cutting of trees and shrubs, and poor water management on irrigated lands.

Most of the deforestation is concentrated in relatively few countries. The "top 10" deforesting countries account for 7.4 million hectares or about 50 per cent of all of the annual forest lost, suggesting that if fundamental changes in land use can be made in those countries it will have a major impact on reducing forest loss.

"Top 10" Deforesting Countries
in Terms of Total Forest Loss (1995)
(area loss in hectares)

Country	ranking	annual loss	country	ranking	annual loss
Brazil	1	-2,550,000	Venezuela	6	-500.000
Indonesia	2	-1,080,000	Malaysia	7	-400,000
P.R. Congo	3	-740,000	Myanmar	8	-390,000
Bolivia	4	-580,000	Sudan	9	-350,000
Mexico	5	-510,000	Thailand	10	-330,000

(FAO, 1997)

Brazil is the country with the largest area of tropical forests and, at the same time, suffers from the greatest deforestation. Until the late 1970s, deforestation in Brazil was considered a minor problem with a limited local impact. However, the situation changed dramatically. During the next 20 years, 50 million hectares of forest were cleared in the states of Rondônia, Pará, Amazonas, Mato Grosso, and Acre, accounting for nearly 14 per cent of the Brazilian Amazon. This was deforestation at an unprecedented scale. Many factors contributed to Brazil's runaway deforestation. The most notorious agents of deforestation were the ranchers who took advantage of existing government subsidies that encouraged expansion of the cattle industry. Incentives and improved access from new highway construction fueled a land speculation frenzy. Ranchers were joined by tens of thousands of small farmers from southern Brazil who were looking for new farming land after having had been displaced by commercial farming estates. On another front, thousands of hectares of forest were cleared to feed the charcoal burners supplying the government-controlled Carajás mine in the State of Pará before eucalyptus plantations were established to supply the mine's energy needs. More recently, pressure has been placed on the "cerrado" woodlands of northern Brazil by commercial farmers who are clearing the land to plant soybeans. Gold mining, flooding from hydroelectric dams, and commercial logging were other important factors.

In addition to the "Top 10" countries, there are other countries that have experienced very high annual rates of deforestation. The total area of forests being lost each year might not be that great but the impact on remaining forests, their biodiversity, and their continued ability to perform their environmental functions and provide their economic goods is being seriously threatened.

Important Deforesting Countries and Regions
in Terms of Annual Rate of Loss (1995)

Country	Ranking	% Annual Loss	Country	Ranking	% Annual Loss
Philippines	1	-3.5	Central America	6	-2.1
Sierra Leone	2	-3.0	Caribbean Islands	7	-1.7
Pakistan	3	-2.9	Cambodia	8	-1.6
Thailand	4	-2.6	Ecuador	9	-1.6
Paraguay	5	-2.6	Myanmar	10	-1.6

(FAO, 1997)

Some countries have witnessed the virtual disappearance of their forests in the last half century. In The Last Frontier Forests, the World Resources Institute describes the extent and location of the remaining undisturbed, biologically-intact tracts of forests. Thirty developing countries are identified as having lost all of their frontier forests. This is not to say that these countries do not have any forests, however the ones that have survived, have been impacted upon so severely that they have lost the capacity to provide the environmental functions (e.g. conservation of biodiversity, hydrologic cycles, moderation of climate) that they once did. Most of this decline has come as a consequence of deforestation. If current trends continue, other countries will join the ranks of nations that have allowed their forests to degrade and disappear.

Developing Countries With No Remaining
Large Tracts of Undisturbed, Biologically-Intact Forests
.

Africa			Latin America & Caribbean	Asia
Angola	Guinea	Senegal	El Salvador	Pakistan
Benin	Guinea-Bissau	Sierra Leone	Haiti	Philippines
Botswana	Kenya	South Africa	Paraguay
Equatorial Guinea	Madagascar	Togo
Eritrea	Mozambique	Uganda
Ethiopia	Namibia	Zambia
The Gambia	Rwanda	Zimbabwe
Ghana	Sao Tome & Pincipe

In 1997 and 1998, there were serious losses in forest cover from the forest fires in Southeast Asia, particularly in the Sumatra and Kalimantan regions of Indonesia. The widespread fires were related to new commercial agricultural projects, land clearing for tree and agricultural plantations, dry residues left in the forest after logging, and slash-and-burn agriculture. The situation was complicated by the very dry climatic conditions caused by the El Niño phenomenon. Despite the concerns of the Ministry of Forests and the advice of numerous missions from international development agencies, the fires could not be contained. The area of forest lost to the fires has not been accurately documented; estimates vary from 170,000 hectares to over 2 million hectares. A devastating fire in 1982 destroyed over 3 million hectares, according to estimates. These fires were associated with clearing brush fallow and forest to establish plantations of oil palm, pulpwood, and rice. In 1998, Mexico and Central America also suffered serious forest fires after an unusually long dry season. The fires were associated with land clearing for new cattle pastures and for slash-and-burn agriculture.

Despite the apparent precision of the quoted figures for the rates of deforestation, the exact area of forest lost each year is not known. The accuracy of estimates is hampered by the lack of reliable time-sequence land use maps, varying standards for forest and non-forest classification, inadequate ground truthing of satellite imagery, and the institutional weakness of government forest departments around the world. Mexico is a good example of the monitoring and reporting problem. According to FAO (FAO 1997), Mexican deforestation in the period 1990-1995 averaged 510,000 hectares annually. However, for the 1980s it is difficult to find a reliable estimate. In a recent government planning document, 13 different estimates are quoted for the annual deforestation rate ranging from 370,000 to 1,500,000 hectares annually with most estimates about 670,000 hectares per annum (Anon, 1995). Most forest loss occurred in southern Mexico in the states of Chiapas, Quintana Roo, Campeche, and Yucatan, as a consequence of the expansion of farming and ranching combined with illegal timber cutting and forest fires.

The monitoring of deforestation has improved in recent years, but it is still far from acceptable. Deforestation estimates are probably conservative and underestimate the rate of forest cover loss. FAO, the UN body responsible for collecting and publishing the statistics, is largely dependent on the information provided to it by the forest departments of each reporting country. The information is often inaccurate, based on old forest inventory and land use data, and at times tempered by political and national security considerations. Unfortunately, considerable caution must be used when drawing conclusions about the extent of deforestation at the national and regional levels from the data currently available.