Three Main Types of Forests: Definition, Subtypes, Importance

Forests are a significant biome of the earth. They are more than just trees. The world’s forests contain a multitude of incredible biodiversity that receive and exchange ecosystem services, which in turn benefits humans. They are the web of life covering multiple million acres of land.  

Forests are integral to nutrient cycles and gas exchange in the environment. The amount of sunlight and rainfall they receive influences their existence. There are three primary types of forest, analyzed according to latitudinal location: tropical, temperate, and boreal. 

This article explores the FAO definition of a forest. We'll also extensively discuss the three types of forests, their subtypes, and their locations worldwide. If this gets you in the mood to share your appreciation of forests, click on over to our forest quotes for some words to inspire forest protection and more.

What is a forest?  

According to the Food and Agriculture Organization, a forest is an area of more than 0.5 hectares, with over 10% tree canopy cover. It is a complex ecosystem and natural resource with trees and underbrush as the primary species.

Forests are the most species-rich ecosystems, covering more than 31% of the Earth. Forest ecosystems contain about 75% bird species, 68% mammal species, and 80% amphibian species. In contrast, tropical forests alone hold  60 percent of all vascular plant species.

Forests are crucial to the survival of the planet and its organisms. They capture and filter water for over 180 million people. We use the natural resources the forest provides to produce paper and wood. They are the primary carbon sequestration source, protecting the soil and its fauna from erosion. 

Types of Forests and their Definitions

Here are the three main kinds of forests and their examples:

1. Tropical Forests

Tropical forests cover 10% of the earth’s land area. These areas are between the Tropic of Cancer and the Tropic of Capricorn. These forest habitats are home to a dense upper canopy of broad-leafed trees, plants, and over 50% of the world’s wildlife. They are the wettest forests in the world.

Tropical forests ensure oxygen and water availability in the carbon and water cycle. They occur in different climates, soil types, and areas prone to fresh or saline water flooding. 

Tropical regions have temperatures between 68 and 77 degrees F, with 79 to 394 inches of annual rainfall. Tropical forests have different layers that play various roles in their survival. Old-growth and giant trees form the top canopy of the forest, while younger trees form the second layer. 

The second canopy is home to animals like birds, reptiles, and jaguars. The last canopy layer, the forest floor, receives little sunlight but is home to diverse fungi, insects, and small plants. These help the soil process carbon and nutrients.

Different tropical forests and their examples:

Tropical rainforests

Tropical rainforests have more plants and animals than other tropical forests, making up 6% of the world’s tropical forests. Two-thirds of the world’s flowering plants are in the tropical rainforest. A hectare of the tropical rainforest has up to 42,000 insect species, 807 evergreen trees of 313 tree species, and 1,500 species of higher plants.

People refer to the evergreen rainforests as the world’s largest pharmacy because we have discovered over one-quarter of all-natural medicines. Others also refer to them as the jewels of the Earth. They have the most stable temperature, rainfall, and sunlight. 

Their average temperature ranges between 20C and 34C, with about 12 hours of sunlight daily. The annual rainfall is between 250 and 450 mm. The driest month in a tropical rainforest can be more than the annual rainfall of other ecosystems like deserts. Examples of evergreen rainforests are the Amazon rainforest and the Congo rainforest.

The Amazon rainforest covers 40% of South America. The Congo rainforest is the second largest tropical forest, covering six countries: the Republic of Congo, the Democratic Republic of Congo, Gabon, Cameroon, the Central African Republic, and Equatorial Guinea. Other rainforests are in Southeast Asia, Madagascar, West Africa, and India.

Tropical dry forests

Tropical dry forests are between 10 and 25 latitudes, between the north and south of the world’s tropical rainforests. They get less rain annually and experience over six months of dry climate. Dry forests, also called seasonal dry forests, tropical seasonal forests, and tropical broad-leaf woodland, comprise 40% of tropical and subtropical forests.

Tropical dry forests contain deciduous trees that shed their leaves during the dry season. Their structure depends on the amount of rain they receive. The tropical dry forest is one of the most endangered forest types. 97% of the dry forest is at risk of extinction because of agricultural land use and industrialization. 

Examples of tropical forests are the dry forests of southeastern Indochina, Madagascar, New Caledonia, Mexico, and the Tumbesian-Andean valleys. The Mexican dry forests are in Guatemala and Mexico, covering 315 sq. km. The dry forests are split into eight ecoregions².

Madagascar dry forests are on the western coast of Madagascar, with over 13,000 flora species. New Caledonia dry forests are on New Caledonia, a large island northeast of Australia. They cover 4,400 sq. km and contain a variety of unique endemic species, like 60 woody trees. Unfortunately, New Caledonia dry forests have the highest number of endangered species.

Cloud forests

Cloud forests are tropical, moist forests in mountainous areas with heavy rainfall. Condensation is also persistent because the mountains deflect moisture-laden air currents into the atmosphere, cooling them. These are montane forests at altitudes between 3,000 to 8000 feet, with a layer of clouds at the top. 

Cloud forests are found in southern Mexico, Central and South America, New Guinea, Southeast Asia, eastern Africa, and parts of the Caribbean. This forest type is home to various climbing and terrestrial ferns, begonias, mosses, orchids, and lichens. Many other herbaceous plants also grow in large, clear areas in cloud forests.

Examples are the Monteverde cloud forest, Santa Elena cloud forest reserve, and Andean cloud forest. The Andean cloud forest extends from 3000 to 8000 ft and is in the Andes. The cloud forests in Peru are home to over 300 bird species.

Mangrove forests

Mangrove forest, also known as mangrove swamp, is a forest type with unique ecosystem services offered to barnacles, oysters, worms, and human beings. It is found near coastal regions. The mangrove tree species adapt and thrive in brackish water. Mangrove forests protect against soil erosion, storms, and flooding. 

Some grow directly in the brackish water, with the roots creating a firm network. Mangrove forests also provide wood, food, and improved water quality. They are habitats of over 1500 species, 15% of which are endangered. We lost one-third of the world’s mangrove forests.

The largest mangrove forest in the world is in North America, from the southern tip of Florida along the Gulf Coast to Texas. Climate change is one of the significant threats faced by mangrove swamps, and many species, like the Bengal tiger, are facing habitat loss. 

2. Boreal Forests

Boreal forests, also known as taiga, are found in Europe, North America, and Asia between 50 and 600 degrees latitude. They cover huge areas of land across the northern hemisphere, including Canada, Siberia, and Scandinavia. Compared to tropical and temperate forests, they have a lower diversity of plants and animals. The animals in boreal forests are used to the cold weather and short growing seasons. 

A boreal forest’s growing season lasts for 130 days. It has the shortest growing season among forest types. Boreal forests contain deciduous and coniferous trees like jack pine, spruce, lodgepole pine, birch, cedar, juniper, hemlock, and trembling aspen. The forest vegetation is a deciduous species⁵.

Boreal forests also contain animal species like forest reindeer, beaver, brown bear, Siberian tiger, lynx, and others that can withstand frigid temperatures as low as -22° Fahrenheit. 

The coniferous forest lacks rich soils, so there is a low rate of organism activity. Its ecosystem dies and regenerates frequently. Boreal forests also have heavy rain annually, varying between 250 and 1000 mm.

Climate change is a major threat to the boreal forest. Eighty percent of the forests are on permafrost, a layer of soil frozen most of the year. As the temperature increases, the permafrost melts, causing soft, swampy ground that causes tree roots to lose stability and die¹.

Boreal Forest Zones

The boreal forest has three zones: the high boreal, middle boreal, and closed canopy boreal zone. The closed canopy boreal zone, also known as lichen woodland, is the southernmost portion of the taiga. It has the most extended growing season, and sunlight can barely penetrate the dense forest roof.

The Canadian boreal forest is an example of a boreal forest. It covers 552 million hectares, 22% of the world’s boreal zone. During the breeding season, the forest houses over 300 bird species, 85 mammal species, and thousands of insects.

3. Temperate Forests

Temperate forests are in temperate regions: eastern North America, northeastern Asia, and Central and Western Europe. They have warmer temperatures than boreal forests but do not have diverse plants and animals like evergreen forests. The daily temperatures in temperate forests are -22° Fahrenheit and 86° Fahrenheit. They receive 750 to 1500 rain annually.

Because temperate forests are in mid-latitude areas, they have four distinct seasons: winter, summer, spring, and fall. The plants and animals in temperate forests are well suited for seasonal changes. The most dominant plants in temperate forests are deciduous trees, which shed their leaves and enter a dormant state during winter. 

Temperate forests have fertile and healthy soils because of the thick layer of leaf litter, mosses, and lichens on the forest floor. Some temperate plant species are gooseberry, white trillium, rhododendron bushes, mistletoe, bright pink snow plants, and dark red pine drops.

Temperate forest wildlife includes wolves, bears, coyotes, mountain lions, eagles, raccoons, squirrels, deer, snakes, hummingbirds, and cougars. These animals adapt to the changing seasons by hibernating. They hibernate during the cold and wake up in spring without food scarcity. Other animals migrate to warmer regions in winter.   

The various types of temperate forests are: 

Temperate deciduous forest

Temperate deciduous forests predominantly contain deciduous trees. They are found in Eastern Asia, Australia, the eastern United States, and New Zealand. The tree leaves change colors, fall off in autumn, and grow back in spring because the leaves of deciduous trees lose moisture quickly⁴.

In deciduous forests, you will find oaks, hickories, maples, elms, basswood, and beeches. Rainfall in this biome ranges between 75 cm and 159 cm [mm].          

Temperate rainforest

The temperate rainforest is a rare biome in areas that receive 300 to 900 mm of rain yearly. These areas are Asia, Canada, Europe, and the United States. Temperate moist forests contain pine, fir, spruce, and hemlock coniferous trees.

Temperate rainforests in Europe spread across the United Kingdom’s seaboard, including Devon, Cumbria, the West coast of Scotland, Cornwall, parts of Ireland, and north and west Wales³.

Conclusion  

We must practice sustainable forest management because we have lost a huge percentage to forest degradation and climate change. We must protect the remaining forests because they help recycle our air and regulate rainfall and local climate conditions. Protecting intact forests helps prevent the negative impact of climate change on wildlife and biodiversity.