Fast facts: Forests of the world

A look at the major forests of the world. Forests can broadly be divided into the following categories:

  • Tropical rainforest
  • Temperate rainforest
  • Taiga/ Boreal forest
  • Temperate hardwood forest
  • Tropical dry forest


Location of tropical rainforests on the global map

TROPICAL RAINFOREST

-- Tropical rainforest is placed roughly within 28 degrees north or south of the equator. They are found in Asia, Australia, Africa, South America, Central America, Mexico and on many of the Pacific Islands.

-- About 80% of the world's biodiversity are found in tropical rainforests.

-- The rainforest is humid. Tall, broad-leaved evergreen trees are the dominant plants, forming a leafy canopy over the forest floor.

-- The trees of a tropical rainforest are so densely packed that rain falling on the canopy can take as long as 10 minutes to reach the ground.


An aerial view of the Amazon Rainforest

-- An area of a rainforest the size of a football field is being destroyed each second.

-- Rainforests once covered 14% of the earth's land surface; now they cover a mere 6% and experts estimate that the last remaining rainforests could be consumed in less than 40 years.

-- The Amazon Rainforest has been described as the "Lungs of our Planet" because it provides the essential environmental world service of continuously recycling carbon dioxide into oxygen. More than 20 percent of the world oxygen is produced in the Amazon Rainforest.

-- Experts agree that by leaving the rainforests intact and harvesting it's many nuts, fruits, oil-producing plants, and medicinal plants, the rainforest has more economic value than if they were cut down to make grazing land for cattle or for timber.

Fast facts: Forests of the world

A tourist crosses a bridge over the Celeste River in the rainforests of Costa Rica

-- Tropical rainforests have also been referred to as "the world's largest pharmacy" because of the large amount of natural medicines discovered in rainforests that are derived from rainforest plants. One in four pharmaceuticals components comes from a plant in the tropical rainforests.

-- Instead of wind, many hummingbirds, other birds, bats and insects are the main source of spreading seeds throughout the forest floor.

-- Thundershowers, on an average, occur 200 out of 365 days a year, in the tropical rainforest region creating a very humid atmosphere.


Temperate rainforest in Great Otway National Park, Victoria

TEMPERATE RAINFOREST

-- Temperate rainforests are coniferous or broadleaf forests that occur in the temperate zone and receive high rainfall. They differ from

-- Well-defined seasons with a distinct winter characterize this forest biome. Moderate climate and a growing season of 140-200 days during 4-6 frost-free months distinguish temperate forests.

-- They occur in eastern North America, north-eastern Asia, and western and central Europe.

-- Temperate rainforests are one of the most productive ecosystems on earth in terms of biomass -- weight of organic matter per unit area. They accumulate as much as 500 to 2,000 metric tons of organic matter per hectare.

Fast facts: Forests of the world

-- Temperate rainforests are naturally rare -- they originally occupied only a fraction of one percent of the earth's land surface.

-- Temperate rainforests are one of the most endangered forest types in the world, more endangered than tropical rainforests. About 55% of the earth's temperate rainforest has been destroyed, making these forests even more rare.

-- Temperate Rainforests Grow BIG Ancient Trees! On the west coast of North America, Western red cedars and yellow cedars can live up to about 2,000 years. A yellow cedar in southern coastal British Colombia is known to be 1,835 years old.

-- They are also known for giant trees, and abundant mosses and epiphytes. Western red cedar trunks can attain a diameter of 20 feet, while in northern California, coastal redwoods can grow almost 400 feet tall. The alerce tree in Chile can live up to about 4,000 years.

Fast facts: Forests of the world

Map showing the location of the Boreal Forests

TAIGA/ BOREAL FOREST

-- The taiga is the largest land habitat - a northern zone of coniferous forests, stretching right round the planet from western Alaska to eastern Siberia. It covers 11% of the earth.

-- The taiga is prone to wildfires. Because of this, many trees have adapted to this by growing thick bark, which can protect the tree from a mild fire.

-- Because of cold temperatures, decomposition is slow in the taiga. Dead vegetation will pile up on the forest floor, making a sponge-like covering. Since decomposition is slow, the soil is thin, and lacking in nutrients.

-- The world's oldest trees can be found in the taiga. The bristlecone pines in California are a prime example. One of them is 4,600 years old!

-- During the summer months, the taiga fills up with millions of insects. Birds, which eat insects, migrate every year for the plentiful food supply.


Fast facts: Forests of the world

TEMPERATE BROADLEAF & MIXED FOREST

-- Temperate broadleaf and mixed forests occur in areas with distinct warm and cool season, which give it a moderate annual average temperature (3 to 15.6 °C). These forests occur in relatively warm and rainy climates, sometimes also with a distinct dry season.

-- Characteristic dominant broadleaf trees in this biome include oaks, beeches, maples, and birches.

-- The term "mixed forest" comes from the inclusion of coniferous trees as a canopy component of these forests.

-- The shortening days of autumn stimulate the plants to withdraw chlorophyll from their leaves, allowing a brief but beautiful display of other pigments before the leaves are shed completely and plants enter an extended period of dormancy.


Fast facts: Forests of the world

Tropical dry forest during the rainy season infested with lianas

TROPICAL DRY FOREST

-- Though these forests occur in climates that are warm year-round, and may receive several hundred centimetres of rain per year, they have long dry seasons which last several months and vary with geographic location. These seasonal droughts have great impact on all living things in the forest.

-- Tropical dry forests are home to a wide variety of wildlife including monkeys, deer, large cats, parrots, various rodents, and ground dwelling birds.

-- The dry forests of central India and Indochina are notable for their diverse large vertebrate faunas.

-- Dry forests are highly sensitive to excessive burning and deforestation; overgrazing and exotic species can also quickly alter natural communities; restoration is possible but challenging, particularly if degradation has been intense and persistent.

-- Degrading dry broadleaf often leaves thorny shrublands, thickets, or dry grasslands in their place.