In ecosystems, organisms interact with each other and their environment. A biome is a very large geographical area that is bigger than an ecosystem.
Biomes are named and categorized based on the climate, plants and animals that exist there.
Biome Definition & Characteristics
A biome is a large area of land that is classified based on the climate, plants and animals that make their homes there. Biomes contain many ecosystems within the same area.
Land-based biomes are called terrestrial biomes. Water-based biomes are called aquatic biomes. Temperatures, precipitation amounts and prevalent organisms characterize the biomes of the world.
Terrestrial Biome Examples
Terrestrial biomes include tropical rainforests, temperate forests, grasslands, deserts, tundra, taiga, savanna and chaparral.
1. Chaparral Biome
Scrubland and few trees characterize chaparral. Chaparral receives between 25 and 30 inches of rain annually, chiefly in winter. Dry summers mean dormancy for many plants. Chaparral can be found throughout southern California and Baja, Mexico.
2. Desert Biome
Desert biomes receive less than 12 inches of precipitation annually and experience very high temperatures. Desert subtypes include hot and dry, semiarid, coastal and cold (Arctic).
Plants are adapted for low rainfall. Animals use burrowing or have nocturnal activity to escape scorching daytime temperatures. Some types of desert species include yuccas, cacti, reptiles, small mammals and burrowing owls.
Example: the Mojave Desert of the American Southwest.
3. Tundra Biome
The coldest biome, the treeless Arctic tundra, receives only about 60 growing days and low precipitation. Plants consist mostly of shrubs, lichens, mosses, sedges and liverworts. Tundra animals include lemmings, caribou, migratory birds, mosquitos, flies and fish.
Example: the High Arctic Tundra in the islands of the Arctic Ocean.
4. Taiga Biome
Taiga (boreal forest) extends south of the Arctic Circle. Taiga endures long, dry winters, cool, wet summers and a 130-day growing season. Annual precipitation ranges from about 16 to 40 inches, typically as snow.
Taiga hosts coniferous trees and low plants. Animal species of the taiga include bears, moose, lynx, deer, hares and woodpeckers, among others.
Example: Interior Alaska-Yukon lowland taiga.
5. Grassland Biome
Savannas receive concentrated rainfall for several months and then drought. Few trees dot the grassy savanna.
Temperate grassland includes steppes, veldts and prairies. Moderate precipitation, rich soils, hot summers and cold winters distinguish this biome. The few trees grow along rivers. Some animals include deer, gazelles, birds, insects and larger predators such as wolves and lions.
6. Rainforest Biome
The tropical rainforest biome contains the world’s greatest biodiversity. Located near the equator, this biome experiences equal day length, warm temperatures and up to 200 inches of rain annually.
These conditions lead to prolific plant growth in levels from the forest floor to the canopy. Epiphytic plants grow on trees and other vegetation. The Amazon Rainforest is an excellent example of a tropical rainforest biome.
Temperate rainforests are found in higher latitudes, with cooler temperatures but significant amounts of precipitation. Evergreens, mosses and ferns thrive there. The Olympic National Park of Washington State hosts temperate rainforests.
7. Temperate Deciduous Forest Biome
Temperate deciduous forests populate eastern North America, central Europe and northeastern Asia. Distinct seasons, consistent precipitation and varied temperatures yield a diverse biome.
Deciduous broadleaf trees, evergreens and other plants flourish. This biome hosts many animal species including deer, rabbits, bears, birds, insects and amphibians.
Example: Great Smoky Mountains National Park.
8. Alpine Biome
The mountainous alpine biome exists only at high altitudes. At those levels, trees do not grow. Alpine regions receive about 180 days of growing season.
A number of shrubs, grasses and heaths thrive. Mammals such as sheep, elk, goats and pikas flourish. Some bird species and several types of insects live there.
Example: the high Sierra Nevada mountain range in California.
Aquatic Biome Examples
Aquatic biomes are related to bodies of water.
Freshwater biomes contain water with very low salt concentrations and include wetlands, lakes, ponds, rivers and streams.
Lakes and ponds undergo thermal mixing. These biomes host fish, waterfowl, algae, crustaceans and microorganisms. Rivers and streams constantly move toward either lakes or oceans. Their current speed affects the kinds of species that live in them, as well as water clarity.
Example: the Columbia River in the Pacific Northwest.
2. Marine Biomes
Marine biomes include the oceans of the world, the largest aquatic biomes, characterized by saltwater. Oceans possess various layers related to sunlight’s penetration.
- The intertidal zone hugs the shoreline and is greatly affected by tides and waves.
- The neritic zone extends to the continental shelf. Enough sunlight penetrates for photosynthesis to take place. Seaweeds are often found here.
- The oceanic or pelagic zone extends farther and experiences a mix of temperatures due to current. Large fish and sea mammals ply this zone.
- The benthic zone is a deep region beyond the continental shelf. Here sea stars, fish and sponges line the ocean floor.
- The abyssal zone represents the deepest ocean zone. High pressure, cold temperatures and essentially no sunlight characterize this zone.
3. Wetlands Biome
Wetlands are shallow bodies of water such as bogs, marshes, swamps and mudflats. They provide habitat for many plants and animals. Water flow is steady in freshwater wetlands.
Example: the Bolsa Chica Ecological Reserve in Orange County, California.
4. Coral Reef Biome
Coral reefs exist in shallow parts of some tropical oceans. Made of calcified remains from coral animals, these reefs build up over time and provide habitat for many underwater species. The Great Barrier Reef of Australia is a large example of a coral reef biome.
5. Estuary Biome
Estuaries lie where ocean meets fresh water. Plants tolerating the salinity changes are called halophytic. Estuaries offer important breeding grounds for crustaceans and well as waterfowl. An example of a large estuary biome is that of the Florida Everglades.
- Lumen Learning Module 25: Ecology of Living Things: Biomes
- UC Museum of Paleontology: The Aquatic Biome
- UC Museum of Paleontology: The Desert Biome
- UC Museum of Paleontology: The Forest Biome
- UC Museum of Paleontology: The Tundra Biome
- UC Museum of Paleontology: The Grassland Biome
- KCET: Exploring Southern California's Wetlands
- WWF: Interior Alaska-Yukon Lowland Taiga
- Radford University Biomes of the World: Tundra
About the Author
J. Dianne Dotson is a science writer with a degree in zoology/ecology and evolutionary biology. She spent nine years working in laboratory and clinical research. A lifelong writer, Dianne is also a content manager and science fiction & fantasy novelist. Dianne features science as well as writing topics on her website, jdiannedotson.com.