TROPICAL DEFORESTATION | Conservation And Sustainable Management Of Tropical Forests

Greatly refined estimates of tropical deforestation have recently been obtained through analyses of changes in forest cover in satellite images. For example, analyses of Landsat imagery covering the Brazilian Amazon indicated an increase in deforested area of 78.000 km2 in 1978 to 230.000 km2 in 1988, or a loss of approximately 6% of the total forested area. Tropical deforestation rates vary greatly across geographic regions, and have shown marked swings over the last decades. Through the 1980s the highest deforestation rates were observed in southeast Asia, but more recently deforestation has shifted to the neotropics and Africa.

In addition to the outright removal of forest, tropical deforestation also acts to fragment landscapes, a pattern of great conservation concern. Tropical forest fragments offer an insufficient amount of habitat for many larger or wide-ranging species of animals, and forest fragments can be seriously degraded by decreased humidity and high wind exposure near edges.

The internal fragmentation of tropical forests caused by selective logging is also a major concern. Studies suggest that low-intensity logging can allow for recovery of primary forest conditions within a couple of decades; however, heavy logging requires a much longer recovery period, and some highly degraded forests may not be able to approach pre-harvest conditions even after hundreds of years.

In many regions construction of logging roads makes forested areas far more accessible to those interested in further exploitation such as subsistence farmers, hunters and fuelwood gatherers. For example, when a commercial logger leaves the concession, subsistence farmers are able to penetrate deeper into the forest than would have previously been the case. Post-logging forest use is becoming increasingly intense due to high population growth rates in many tropical countries.

One partial answer to these difficulties is development of sustainable forestry practices in combination with improved conservation of remaining tropical forests. "Natural forest management" in which gap phase dynamics is emulated by harvesting has been advocated as a means of mitigating losses of diversity and ecosystem function while allowing continued timber harvests. Alternative harvesting practices, such as planning of harvest areas and skid trails, tree marking and directional felling, can be used to reduce the residual impacts of the harvest. Recent studies suggest that such reduced-impact logging in tropical forests can dramatically reduce post-harvest tree mortality. This results in greater retention of forest biomass, increased long-term value of the forest in terms of timber commodities, and more rapid recovery of pre-harvest forest conditions.

ELIMINATING SMOKE DOES NOT NECESSARILY CUT CARBON EMISSIONS

Land-clearing techniques exist that do not produce smoke, including biological methods to accelerate decomposition and various mechanical techniques that chip or shred biomass, either for mulching on the site or for transport off site for disposal or sale. All of these `no-burn' techniques presently are more expensive than burning. Moreover, as noted above, burning produces many benefits for land users.

Research may be able to reduce the economic and technical disadvantages (compared to burning) of certain techniques, such as mulching. If they are feasible, policies to regulate the timing of burning and new techniques for land clearing without burning could-over time- address part of the regional smoke problem.

However, it must be emphasized that unless a significant portion of the biomass from land clearing is used to manufacture wood products with a long useful life (instead of simply decaying), these measures will only have a short-term effect on C emissions.

Moreover, the attractiveness of technological alternatives to clear land without burning, or the level of subsidies required for adoption of these techniques, also are infuenced by national policies, such as timber export taxes.

DEFINITION OF FOREST LANDSCAPE

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Definition of forest landscape is the large-scale view of a forest. When industrial timber managers use the term “forest landscapes,” they are usually concerned with scenery and visual impacts. In the context of an ecosystem-based approach, however, a forest landscape is a mosaic of interconnected, interdependent stands or patches that are repeated in a pattern across the larger landscape. This pattern has both spatial and temporal components.

An ecosystem-based approach requires that all planning and activities begin at the regional/landscape level. When planning for human use, landscape level decisions are made for watersheds of small to moderate size (less than 5,000 hectares to about 50,000 hectares, or 12,000 to 125,000 acres). In sub-regional or regional planning processes, forest landscape level considerations are expanded to large watersheds encompassing hundreds of thousands of hectares/acres.

In planning and carrying out forest uses, particularly timber management, many people tend to focus on small forest parcels. This is a result of our limited spatial view, short time frames, and cultural conditioning. In contrast, an ecosystem-based approach requires that all planning and activities start at the landscape level. The character and condition of the forest landscape dictate what is ecologically possible at the stand level.

The character of a forest ecosystem refers to how a forest works, from the landscape level to the stand or patch. For example, forests that have frequent fires have a different character than forests where wind and root decay are the primary agents of disturbance. Some forests are characterized by steep slopes, shallow soils, and well-defined drainage patterns, while other forests have gentle slopes, cold soils, and diffuse drainage patterns.

Forests of a different character will have different composition and structures, and therefore differences in how they function. Different composition, structures, and functioning lead to different kinds of ecological limits to human use. Ecological limits are natural factors or processes that are easily damaged or degraded if modified by human uses. For example, steep and/or wet slopes impose ecological limits because, if disturbed, they are likely to erode, causing problems like soil loss and siltation of streams. Cold soils are an ecological limit because nutrient cycling occurs in shallow organic layers which may be easily damaged by many types of human activities.

The condition of a forest describes how human uses have modified forest functioning from the landscape level to the stand or patch level. Conventional timber management frequently results in negative impacts, like fragmentation, loss of old growth, and soil degradation. An ecosystem-based approach protects forest composition and structure and respects the ecological limits of forests to various human uses. By respecting ecological limits ecosystem-based approaches avoid degradation of short- and long-term forest functioning.
Ecological limits to human use are determined by describing and interpreting the character and condition of, first, the forest landscape, and then the forest stand or patch.

Types of Rainforests

Rainforests are found throughout the world, not only in tropical regions, but also in temperate regions like Canada, the United States, and the former Soviet Union. These forests, like tropical rainforests, receive abundant, year-round rainfall, and are characterized by an enclosed canopy and high species diversity, but lack the year-round warmth and sunlight associated with tropical rainforests. However this book focuses on tropical rainforests, and these are the only forest forms discussed here.

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 overwhelming diversity of the tropics.

EQUATORIAL EVERGREEN RAINFOREST VS. MOIST FOREST

There are two major types of wet tropical forests: equatorial evergreen rainforests and moist forests, which includes monsoon forests and montane/cloud forests. Equatorial rainforests, often considered the "real rainforest," are characterized by more than 80 inches (2,000 mm) of rain annually spread evenly throughout the year. These forests have the highest biological diversity and have a well-developed canopy "tier" form of vegetation. Roughly two-thirds of the world's tropical wet forests can be considered the equatorial type. These forests are near the equator where there is very little seasonal variation and the solar day is a constant length all year round. The greatest expanses of equatorial rainforest are found in lowland Amazonia, the Congo Basin, the Southeast Asian islands of Indonesia, and Papua New Guinea.

Tropical moist forests are found at a greater distance from the equator where rainfall and day length vary seasonally. These forests get "only" 50 inches (1,270 mm) of rain annually and are markedly distinguished from equatorial rainforests by a cooler dry season. During this dry season, many trees shed some or even all their leaves, creating a seasonal reduction of canopy cover and allowing more sunlight to reach the forest floor. The increased sunlight reaching the forest floor allows the growth of vigorous understory vegetation not found in lowland equatorial forest. Such moist forest is found in parts of South America, the Caribbean, West Africa, and Southeast Asia, especially Thailand, Burma, Vietnam, and Sri Lanka.

PRIMARY VS. SECONDARY FOREST

Throughout this site, other books, and discussions about tropical rainforest, the term "primary forest" is used. Primary forest refers to untouched, pristine forest that exists in its original condition. This forest has been relatively unaffected by human activities. Primary rainforest is often characterized by a full ceiling canopy and usually several layers of understory. The ground floor is generally clear of heavy vegetation because the full canopy allows very little light, necessary for plant growth, to penetrate. Occasionally, when a canopy tree falls, a temporary "light gap" is opened in the canopy, allowing growth of floor and understory species. Primary forest is the most biologically diverse type of forest.

Secondary forest is rainforest that has been disturbed in some way, naturally or unnaturally. Secondary forest can be created in a number of ways, from degraded forest recovering from selective logging, to areas cleared by slash-and-burn agriculture that have been reclaimed by forest. Generally, secondary forest is characterized (depending on its level of degradation) by a less developed canopy structure, smaller trees, and less diversity. Due to the lack of a full canopy, more light will reach the floor, supporting vigorous ground vegetation. "Jungle" is the term often applied to secondary forest with dense ground growth, but it is also applied to some tropical moist forests where seasonal variations permit thick ground growth.

Primary versus total forest cover for selected tropical countries

		Total land area		Total forest cover 2005				Primary forest cover 2005				Total deforestation 1990-2005		Loss of primary forest 1990-2005
Country		(1000 ha)		(1000 ha)		% of total land area		(1000 ha)		% of total land area		% of 1990 forest cover		% of 1990 primary forest cover
Bolivia		109,858		58,740		54.2		29,360		26.7		-6.5		-6.5
Cambodia		18,104		10,447		59.2		322		1.8		-19.3		-58.0
Congo		34,200		22,471		65.8		7,464		21.8		-1.1		-1.1
Costa Rica		5,110		2,391		46.8		180		3.5		-6.7		-29.4
Ghana		23,854		5,517		24.2		353		1.5		-25.9		0.0
Guatemala		10,889		3,938		36.3		1,957		18.0		-17.1		-17.0
Malawi		11,848		3,402		36.2		1,132		9.6		-12.7		-34.5
Malaysia		32,975		20,890		63.6		3,820		11.6		-6.6		0.0
Nigeria		92,377		11,089		12.2		326		0.4		-35.7		-79.0
Senegal		19,672		8,673		45		1,598		8.1		-7.2		-9.2
Thailand		51,312		14,520		28.4		6,451		12.6		-9.1		0.0
Brazil		851,488		477,698		57.2		415,890		48.8		-8.1		-9.7
Colombia		113,891		60,728		58.5		53,062		46.6		-1.2		-1.5
Côte d'Ivoire		32,246		10,405		32.7		625		1.9		1.8		0.0
Liberia		11,137		3,154		32.7		129		1.2		-22.3		0.0
Madagascar		58,704		12,838		22.1		10,347		17.6		-6.2		-1.5
Mexico		195,820		64,238		33.7		32,850		16.8		-6.9		-15.3
Panama		7,552		4,294		57.7		3,023		40.0		-1.9		-18.4
Papua New Guinea		46,284		29,437		65		25,211		54.5		-6.6		-13.7
Peru		128,522		68,742		53.7		61,065		47.5		-2.0		-2.9
Philippines		30,000		7,162		24		829		2.8		-32.3		0.0
Sri Lanka		6,561		1,933		29.9		167		2.5		-17.7		-35.0

The Food and Agriculture Organization of the United Nations estimates that primary forests now account for 36 percent of total forest area, but are being lost or modified at a rate of 6 million hectares a year through deforestation or selective logging. Selective logging, where only one or two valuable tree species are harvested from an area, was recently found to be degrading forests in the Amazon twice as fast as deforestation figures indicate.

Scientists do not know how long it takes for secondary forest to attain the structure and levels of biodiversity of primary forest. A recent study by conducted as part of the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) determined that trees in the Central Amazon may, on average, be several hundred years old, suggesting that primary forests take a long time to develop.


LOWLAND VS. MONTANE FOREST

Lowland tropical rainforest refers to the majority of tropical rainforest, that is, forest which grows on flat lands at elevations generally less than 3,300 feet (1,000 m)—although elevation may vary. Lowland primary forest, often characterized by more than five forest tier levels, is usually taller and more diverse than montane forest. It has a greater diversity of fruiting trees; hence more animals specially adapted to feed on their fruits and more large mammals. Lowland rainforest is far more threatened than montane forest because of its accessibility, more suitable soils for agriculture, and more hardwoods valuable as timber. In many countries, virtually all lowland primary forest is gone, while montane forest still remains.

Tropical montane rainforest is forest that grows on mountains and above an altitude of 3,300 feet. High montane forest, above 6,600-10,000 feet (2,500-3,000 meters) in elevation, is often manifested as "cloud forest," forest that receives the majority of its precipitation from mist or fog that passes up from the moist, humid lowlands. The trees of cloud forests are typically shorter than those of lowland forest resulting in a less-developed canopy. Nevertheless, cloud forest trees are heavily burdened with epiphytes that thrive with the abundance of moisture from the passing fog. Trees in places like the lower elevations of the Andes in Ecuador, Peru, Colombia, and Venezuela; Central America (Monteverde in Costa Rica in particular); Borneo (Mount Kinabalu); and Africa (Ethiopia, Kenya, Rwanda, Zaire, Uganda), are frequently green with dense moss and beautiful, often rare, orchids.

Patches of cloud forests tend to have many endemic species, because they are often isolated from other sections of cloud forest by valleys and ridges. These species are prevented from migrating to other forest areas by these obstacles to the sides, by the lowland forest below, and by steep cliffs above. Cloud forests are home to an abundance of hummingbirds, frogs, and epiphytes like orchids, bromeliads, and mosses. Many of these species are endemic to a single locality, like the Golden toad of Monteverde, Costa Rica, a species which is now believed to be extinct. Cloud forests generally lack an abundance of large-bodied mammals due to the small number of fruiting trees.

Tropical montane forests are especially in the South American Andean region, where much of the forest has been cleared for agriculture. Of the continent's endangered species, a disproportionate number of those are found in yungas, the regional name for tropical montane forests in the Andes. These forests have also been little studied.

Above 10,000 feet (3,300 m), cloud forest may give way to sub-alpine and alpine forest. These habitats have less rain, fewer trees, and reduced biodiversity compared with lower elevation forests.

Chart showing percentage cover of world forests. Rainforests are a subsection of "Tropical forests".

OTHER TYPES OF FOREST

SEASONAL OR MONSOON FOREST
Monsoon forests are tropical moist or seasonal rainforests found primarily in Asia (India/Sri Lanka to China), West and East Africa, Northern Australia, and Eastern Brazil. In this type of forest there is a distinct cooler dry season and a distinct wet season. These forests tend to be less diverse and more dwarfed in terms of tree size in comparison to typical equatorial rainforests.

Monsoon forests are highly threatened worldwide by clearing for cultivation, especially in West Africa, where over 90 percent of the coastal rainforests and the monsoon forests have been cleared.

IGAPÒ FOREST

Flooded forest in Brazil | more Photo by R. Butler

Igapò forest is rainforest that is regularly inundated for extended periods during the flood season (sometimes considered permanently flooded rainforest). The best known of such forests are found in the Amazon Basin where they make up about 2 percent of the total rainforest. Igapò forest trees are shorter than those of non-flooded forest because of the instability caused by the wet, poorly drained soils (hence it is sometimes known as "swamp forest") and characterized by certain tree species like Cecropia, Ceiba, and Mauritia palms (also known as the aguaje palm). Many igapò tree species have stilt roots and flying buttresses to lend structural support. Igapò forest is flooded (4-10 months of the year) and flooding is usually predictable. Fish play an important role in seed dispersal in this forest system.

VÀRZEA FOREST
Vàrzea forests are floodplain forests which flood seasonally. Unlike swamp forests, varzeà forests have relatively rich soils from the annual replenishment of nutrients from whitewater rivers. Because these forests are more suitable for agriculture than typical rainforest, they are some of the most threatened. Even in the Amazon where vast majority of such forests are found, vàrzea are disappearing rapidly for development.

Floodplain forests, especially those located on river banks and islands, are often short-lived due to the meandering nature of tropical lowland rivers which eat away at the forests' base. According to Amazon Headwaters, a book by Michael Goulding and his colleagues, research in Peru suggests that most floodplain forests are rarely older than 200 years and may have turnover rates exceeding 1.6 percent, implying an average tree life of 63 years. For this reason, floodplain forests are nearly always in some stage of succession with pioneer species like Cecropia being replaced with Kapok (Ceiba) and fig trees further away from the river.

HEATH FOREST
Heath forests are found on well-drained, sandy soils that are extremely nutrient-poor. These forests are characterized by certain tree species tolerant of the poor, acidic soil conditions and are considerably "stunted" in comparison with typical rainforests. More light reaches the forest floor making for dense tree growth. Heath forests, also known as blackwater or caatinga forests, are drained by blackwater rivers and are found primarily in the Amazon Basin (the Rio Negro drainage), but also in parts of Asia.

PEAT FOREST  [news and information on peatlands]
Peat forest is found in small parts of Africa, northeastern South America, and large areas in southeast Asia (especially Borneo and Sumatra). These swamp forests appear in places where dead vegetation becomes waterlogged and accumulates as peat. The peat acts as a sort of sponge withholding moisture at times of little rainfall and absorbing monsoon rains. When peat swamp forests are drained for agricultural projects, they become highly susceptible to combustion. Under the dry el Niño conditions of 1997-98, thousands of fires raged in the peat swamps of Indonesia. Fires in peat swamps are extraordinarily difficult to extinguish because the conflagration continues in the deeper layers of peat.

TERRA FIRME FOREST
Terra Firme literally means "firm earth" and refers to rainforest that is not inundated by flooded rivers. This forest is noticeably taller and more diverse (>400 species/hectare in some areas) than igapò or flooded forest. It is found only on dry, well-drained soils and is characterized by such species as Brazil nut trees, Rubber trees, and many tropical hardwood trees.

MANGROVE FOREST [news and information on peatlands]
Mangrove forest is found in silt-rich, saline (brackish water) habitats worldwide, generally along large river deltas, estuaries, and coastal areas. It is characterized by low tree diversity, almost exclusively mangroves, with a low broken canopy. Mangroves are evergreen trees and shrubs that are well adapted to their salty and swampy habitat by having breathing roots (pneumatophores) that emerge from the oxygen-deficient mud to absorb oxygen.

Mangroves in Honduras. Photo by R. Butler. More mangrove photos

Mangrove swamps are home to numerous bizarre amphibious fish species like the mudskippers of eastern Africa to Australia and Anableps, the so-called four-eyed fish of the New World. Mudskippers are renowned for their preference for terrestrial haunts over aquatic realms. These fish spend more time on floating debris, tree toots, and plants than they do in the water where they only go to escape predators. Watching a group of Mudskippers reminds the observer of what our ancestors must have looked like when they first left the ocean for life on land. Mudskippers are highly intelligent fish that feed primarily on insects and crustacean.

A second amphibious species found in mangrove forests is the Anableps. a species widespread in the New World from Central America to northern South America. Most notable about its physical features is its double-lobed eyes which allow it to see both above and below the water line as it swims along the water surface. The Anableps, too, regularly leaves the water to perch on tree roots and rocks.

Mangrove forests are some of the most threatened ecosystems on the planet because of their proximity to the ocean (prime resort/development property) and the tendency for local people and governments to undervalue the services they provide. A recent study by the Food and Agriculture Organization of the United Nations found that 20 percent of the world's mangrove forests have disappeared since 1980, mostly due to farming, harvesting for timber and charcoal, freshwater diversion, real estate development, and conversion for tourism.

According to the Environmental Justice Foundation, about 38 percent of global mangrove deforestation is linked to shrimp farm development. Mangrove clearing for commercial shrimp and prawn hatcheries is particularly prevalent in Southeast Asia. Ironically this form of aquaculture has come at the expense of the natural fish and shrimp hatchery.

The destruction of mangrove forest has dire implications for the fisheries industry, since these forests provide an important spawning ground and serve as a nursery for many commercially important species. In addition, mangrove forest protects coastal regions against storm damage and erosion. Research conducted following the 2004 tsunami in Asia found that areas forested with mangroves suffered considerably less damage than areas without tree vegetation.

Mangrove forests are slow to recover from clearing and degradation. For example, seismic lines only a few meters wide in the mangrove forest of Nigeria were still visible by air a decade after they were cut.


Review questions:

• What is the difference between primary and secondary forest?
• True or false—Cloud forest is found in mountainous areas.
• True or false—flooding is common in the Amazon rainforest.
• Why are mangrove forests important?
• Why are mangrove forests being destroyed?

Felling of tress to success Gerhan On Indonesia

Currently Indonesia loses about 1.6 - 2 million hectares of forest every year. The scale and rate of deforestation of this magnitude is unprecedented. Recent survey and the results can be accounted for on Indonesia's forest cover predicted, that the forests of lowland Dipterocarpaceae will disappear from Sumatra and Kalimantan by 2010 if current trends continue unchecked (Holmes, 2000).
Forest destruction in Indonesia that reaches approximately 2 million hectares per year resulting in a loss of about Rp 83 billion per day or Rp 30.3 trillion per year.

 

Land Clearing by Burning

So Gerhan Project seeks to reduce the amount of degraded forest area. But if there is an understanding that Gerhan is just a tree planting project then this happens, people cut down forests and clearing land for Gerhan project forward.  In terms of planting and maintenance projects may be successful but the degraded forest area to be increased rather than diminished.

Things are even worse land-clearing activities carried out by clearing and burning. Land to be losing nutrients, especially nitrogen because nitrogen is an element that is flammable. Soil microorganisms can not survive so the process of decay and nutrient turnover become inhibited. The bacteria are symbiotic with the roots of plants to enrich the soil becomes dead. Fungi are beneficial for plant growth such as mikorhiza lost and gone. Plus the increased surface erosion due to loss of vegetation cover on the soil surface. Next>>>

The importance of forests

What is The Forest 

Forest - is a large area of land covered with trees. But a forest is much more than just trees. It also includes smaller plants, such as mosses, shrubs, and wildflowers. In addition, many kinds of birds, insects, and other animals make their home in the forest. Millions upon millions of living things that can only be seen under a microscope also live in the forest.

Climate, soil, and water determine the kinds of plants and animals that can live in a forest. The living things and their environment together make up the forest ecosystem. An ecosystem consists of all the living and nonliving things in a particular area and the relationships among them.

The forest ecosystem is highly complicated. The trees and other green plants use sunlight to make their own food from the air and from water and minerals in the soil.

The plants themselves serve as food for certain animals. These animals, in turn, are eaten by other animals. After plants and animals die, their remains are broken down by bacteria and other organisms, such as protozoans and fungi. This process returns minerals to the soil, where they can again be used by plants to make food.

Although individual members of the ecosystem die, the forest itself lives on. If the forest is wisely managed, it provides us with a continuous source of wood and many other products.

Before people began to clear the forests for farms and cities, great stretches of forestland covered about 60 per cent of the earth's land area. Today, forests occupy about 30 per cent of the land. The forests differ greatly from one part of the world to another. For example, the steamy, vine-choked rain forests of central Africa are far different from the cool, towering spruce and fir forests of northern Canada.

  

The importance of forests 

Forests have always had great importance to people. Prehistoric people got their food mainly by hunting and by gathering wild plants. Many of these people lived in the forest and were a natural part of it. With the development of civilization, people settled in cities. But they still went to the forest to get timber and to hunt.

Today, people depend on forests more than ever, especially for their (1) economic value, (2) environmental value, and (3) enjoyment value. The science of forestry is concerned with increasing and preserving these values by careful management of forestland.

Economic value. Forests supply many products. Wood from forest trees provides lumber, plywood, railroad ties, and shingles. It is also used in making furniture, tool handles, and thousands of other products. In many parts of the world, wood serves as the chief fuel for cooking and heating.

Various manufacturing processes change wood into a great number of different products. Paper is one of the most valuable products made from wood. Other processed wood products include cellophane, plastics, and such fibers as rayon and acetate.

Forests provide many important products besides wood. Latex, which is used in making rubber, and turpentine come from forest trees. Various fats, gums, oils, and waxes used in manufacturing also come from trees. In some primitive societies, forest plants and animals make up a large part of the people's diet.

Unlike most other natural resources, such as coal, oil, and mineral deposits, forest resources are renewable. As long as there are forests, people can count on a steady supply of forest products.

Environmental value. Forests help conserve and enrich the environment in several ways. For example, forest soil soaks up large amounts of rainfall. It thus prevents the rapid runoff of water that can cause erosion and flooding. In addition, rain is filtered as it passes through the soil and becomes ground water. This ground water flows through the ground and provides a clean, fresh source of water for streams, lakes, and wells.

Forest plants, like all green plants, help renew the atmosphere. As the trees and other green plants make food, they give off oxygen. They also remove carbon dioxide from the air. People and nearly all other living things require oxygen. If green plants did not continuously renew the oxygen supply, almost all life would soon stop. If carbon dioxide increases in the atmosphere, it could severely alter the earth's climate. 

Forests also provide a home for many plants and animals that can live nowhere else. Without the forest, many kinds of wildlife could not exist.

Enjoyment value. The natural beauty and peace of the forest offer a special source of enjoyment. In the United States, Canada, and many other countries, huge forestlands have been set aside for people's enjoyment. Many people use these forests for such activities as camping, hiking, and hunting. Others visit them simply to enjoy the scenery and relax in the quiet beauty.

Source : World Book 2005