What is a biome?
Biomes are the largest aggregations of living organisms present in a given environment. They encompass a range of habitats, including deserts, forests, grasslands, and tundra. Within these broad generalities exist distinct ecosystems with their own microclimates, vegetation types, soil structure, and water availability.
Flora and fauna within each biome are unique to that particular environment and provide an ideal setting for intricate ecological processes to take place. These processes range from the cycling of nutrients in soils to the hunting habits of predators atop the food chain.
The relationship between different species is vital to maintaining biomes as dynamic living communities, and understanding how changes in one aspect can disrupt others is essential for their preservation.
What are the different biomes of the world?
The world is composed of various different biomes, each with its own set of characteristics and organisms. Scientists disagree on the exact number of biomes, but the World Wide Fund for Nature (WWF) recognizes 26 types of biomes. These include aquatic (water) biomes like oceans and freshwater and terrestrial (land) biomes like deserts, forests, grasslands, and tundra.
The five major terrestrial biomes include:
- Aquatic
- Desert
- Forest
- Grassland
- Tundra
The aquatic biomes are further divided into oceanic plankton and nekton, balanoid-gastropod-thallophyte, pelecypod-annelid, and coral reef. The desert biome consists of hot and dry regions, like the Sahara Desert.
The forest biome includes temperate deciduous forests, coniferous forests, and woodlands. The grassland biome is composed of savannas and steppes. The tundra biome is found in colder regions and typically consists of shrubs, mosses, and lichens.
Types of biomes in the world
Tropical Rainforest
A tropical rainforest is a type of biome found in areas located between 23.5 degrees N and 23.5 degrees S latitude. Characterized by an average temperature of 20-25 degrees Celsius, these rainforests experience two distinct seasons: wet and dry.
They are also distinguished by the amount of rainfall they receive, with an average of 2000 mm annually, making them one of the most species-rich biomes in the world. In addition to receiving sunlight, the thick vegetation of tropical rainforests absorbs moisture, which then evaporates and falls again as rain, thus completing the cycle.
Tropical rainforests are home to a wide variety of plants, such as orchids, palms, vines, ferns, and mosses, as well as a plethora of animals, such as bats, small mammals, snakes, jaguars, monkeys, and many species of birds.
These forests occur in Asia, Africa, South America, Central America, and numerous Pacific islands. The deforestation of these regions is a major contributor to climate change, as the burning of trees releases carbon dioxide into the atmosphere.
Tropical rainforests are one of the most common biomes in the world due to their ability to provide shelter to a wide range of species, their warm climate and high rainfall, and their abundance of plants and animals. They are also one of the most important biomes for the conservation of biodiversity. As such, it is important to protect and preserve these vital ecosystems.
Temperate Forests
Temperate forests are terrestrial habitats that are dominated by trees and are found in temperate regions of the world, such as North America, Asia, and Europe.
These forests have well-defined seasons, with distinct winters, 140-200 days of a growing season, and 4-6 frost-free months. The trees are deciduous, meaning that they shed their leaves annually, and the temperature varies greatly, from -30 to 30 degrees Celsius.
Common trees in temperate forests include oak, hickory, maple, beech, and ash. The main fauna in these forests is diverse, ranging from small mammals like squirrels, mice, and chipmunks to large mammals such as deer, bears, and wolves.
Taiga Or Boreal Forests
The taiga or boreal forests are a type of terrestrial biome characterized by long, cold winters and short, cool summers. The flora is made of frost-tolerant evergreen conifers, such as spruce, alder, birch, and juniper.
The fauna is also adapted to survive in the cold climate and consists of species such as moose, wolves, bears, fishers, wolverines, lynx, snowshoe hare, grouse, siskins, crossbills, northern vole, squirrels, and birds. These animals depend on coniferous trees, such as spruce, for food and shelter.
The low temperatures lead to slow decomposition and high litter accumulation, resulting in the accumulation of up to 60% of the biomass in litter and humus.
The soils are heavily leached, and permafrost often underlies the soil, leading to shallow root systems and a reliance on mycorrhizal associations for nutrient uptake.
Deserts
Deserts are arid expanses where desiccating winds and sparse precipitation reign. Covering a fifth of Earth’s land surface, these hot and cold biomes flourish in Central America, South Asia, parts of Africa, and Australia.
Dry climates challenge flora to survive. Plants form adaptations such as long roots and wax-coated leaves to absorb scarce groundwater. Animal life, too, adapts by burrowing beneath sandy terrain for refuge from fierce temperatures.
Animals like foxes, snakes, lizards, beetles, and camels can even run on minimal water supplies. These creatures all make the desert their home, adjusting their behavior to cope with inhospitable conditions.
Tundra
A tundra is a type of biome characterized by extremely low temperatures, little precipitation, and a short growing season. It is found in two regions – the Arctic tundra, which encircles the North Pole and has a permanent layer of ice known as permafrost, and the Alpine tundra, which is found in the high-altitude mountain regions of the world.
The Arctic tundra is a cold, vast, treeless area of low, swampy plains in the far north around the Arctic Ocean, and the alpine tundra is a biome that exists at the tops of high mountains. Both regions lack trees and have night temperatures that are usually freezing.
It is impossible for trees to grow in the Arctic tundra due to a permanently frozen subsoil.
The tundra biome is important in the world because it helps regulate climate, especially in the Arctic region. It also provides unique habitats for a variety of rare and threatened species.
Furthermore, the Arctic tundra contains large amounts of carbon, which can help limit the effects of climate change if it is allowed to remain intact.
Grassland
A grassland biome is an area of land covered mainly with grasses and other herbs and low shrub-like vegetation and is characterized by hot, dry climates. It is a common type of biosphere in the world because of its moderate precipitation and dark, fertile soil, coupled with its ability to withstand occasional droughts, seasonal fires, and its plentiful species of grasses.
It is also a habitat for many species, such as zebras, gazelles, wild horses, owls, spiders, and lions, making it a vital part of the world’s ecosystem.
Grasslands are present in many regions, including South Africa, central North America, the steppes of the former Soviet Union, South America, Africa, and Eurasia.
These areas are known by different names, such as prairies and veld in the US and South Africa, respectively. Grasslands are used for grazing and growing cereal crops but have unfortunately lost some of their original prairie animals due to hunting.
Nevertheless, grassland biomes are a crucial part of global biodiversity and remain a powerful force in the health of the planet.
Savannah
The Savannah biosphere is a unique ecosystem due to its mix of grasses, small trees, and occasional fires. It is situated in a transitional zone between tropical forests and deserts, receiving 6-8 months of precipitation followed by a period of drought.
This climate results in deciduous trees, which can survive long dry periods and regular fires that help to maintain a balance between trees and grasses.
Additionally, it has a rich diversity of large herbivores and predators, and the presence of dung beetles aids in the nutrient cycle. All of these elements combined make the Savannah a unique and dynamic biosphere.
Freshwater
A freshwater biome is an aquatic habitat with a low salt concentration (less than 1%), which includes ponds, lakes, rivers, and wetlands. We get our drinking water from these biomes, and we use it for irrigation.
To survive in this environment, plants and animals have developed many adaptations that allow them to conserve salts, such as specialized organs and membranes.
Freshwater biomes contain various biodiversity, including algae, aquatic plants, turtles, ducks, snakes, plankton, and more.
Also, these biomes contain hydrophytes, which are plants adapted to living in standing water. Furthermore, freshwater biomes are prone to pollution due to runoff containing fertilizer and other wastes and industrial dumping.
This can lead to abnormally rapid algae growth and the accumulation of dead organic matter, which makes the water unusable and can kill many of the organisms living in the habitat.
Marine
A marine biome is a body of water that consists of saltwater and is the largest biome on Earth, covering approximately three-quarters of the Earth’s surface. It consists of oceans, coral reefs, and estuaries and provides important habitats for a wide variety of marine organisms.
Flora and fauna in the marine biome are diverse and include octopuses, whales, sharks, jellyfish, sea birds, seaweeds, plankton, baleen whales, penguins, orcas, seals, albatrosses, petrels, terns, and fulmars.
The marine biome is divided into five distinct zones, each characterized by different characteristics. These zones are the polar, temperate shelf and seas, temperate upwelling, tropical upwelling, and the open sea. The polar zone is characterized by its low temperature and salinity levels and is home to a variety of plankton that supports many species of whales, penguins, seals, and birds.
The temperate shelf and seas zone is relatively shallow and contains temperate estuaries like the Chesapeake Bay, which are important for migratory birds and other marine life. The temperate upwelling zone is characterized by upwelling cold, nutrient-rich waters along the coasts of North and South America and includes important commercial fisheries.
The tropical upwelling zone is also characterized by upwelling cold, nutrient-rich waters in tropical seas and contains some of the most bio-productive areas in the world. Finally, the open sea zone is deep and contains hydrothermal vents, cold seeps, and the benthic zone.
The marine biome is under threat due to human activities, such as overfishing and pollution, and conservation and preservation efforts have become a global concern.
Where are biomes found?
Biomes can be found all around the world, in different continents and regions, depending on their climate and geography. Aquatic biomes include both freshwater and marine biomes, such as lakes, rivers, oceans, and coral reefs.
Grasslands are found in Africa, Australia, India, South America, South Africa, Hungary, Argentina, Uruguay, North America, and Russia. Forests can be found in various areas of the world, including tropical rainforests and temperate rainforests.
Deserts are found in arid regions with low levels of precipitation, such as the Sahara in Africa and the Mojave in North America. Lastly, tundra biomes are found in the Arctic and Antarctic regions.
How are biomes categorized?
Biomes are categorized according to the predominant vegetation and characteristics of the animals and plants adapted to that particular environment. There are a variety of classification schemes used to identify the different biomes on Earth.
For example, the World Wide Fund for Nature (WWF) has identified 26 types of biomes, and NASA (National Aeronautics and Space Administration) has identified seven major types of biomes. National Geographic has identified five major types of biomes.
The five major biomes are aquatic, desert, forest, grassland, and tundra biomes. Each of these biomes can be further divided into numerous sub-habitats. For example, the aquatic biome can be divided into freshwater and marine sub-habitats. Within each of these sub-habitats, there are various species that have adapted to specific environmental conditions.
Ultimately, there is no consensus on how biomes should be classified, as different organizations and scientists have different methods of categorizing them. As new research is conducted and we learn more about the world around us, the definition and categorization of biomes will continue to evolve.
What factors affect biomes?
Biomes are affected by several factors, including climate, landforms, altitude, and soil. The climate is the most important factor in determining the types of biomes found on Earth, as it dictates the amount of rainfall and temperature.
The climate can vary across different zones, including the tropical, temperate, and polar zones, which are nearer to the equator, away from the equator, and furthest from the equator, respectively.
Landforms, such as mountain ranges, large bodies of water, and coastal regions, can also affect the climate, resulting in rain shadows that create drier, desert regions or milder coastal climates. Altitude can also affect climate, making some mountains have multiple biomes in different climates.
Finally, the type of soil can affect biomes to a lesser degree by providing the necessary nutrients for different species of plants and animals to survive.
Where are the different biomes located?
The different biomes of the world are located in a variety of locations across the globe. The Arctic tundra is found in northern Alaska, while the tropical rainforest is found in Brazil. Grasslands, deserts, and mountains can be found throughout the world.
Freshwater and marine biomes are found in rivers, lakes, and oceans. Each biome provides a unique environment that is home to a wide range of species of plants and animals that have adapted to the conditions of their particular biome.
How does vegetation vary between biomes?
Biomes are broad, geographically distinct regions that share characteristics of vegetation and climate. Variations in precipitation, temperature, topography, soil type, and other factors give rise to different types of vegetation within biomes.
Grasses dominate temperate grasslands, with shrubs and wildflowers covering the land in warmer months. Arid deserts boast waist-high succulents such as cacti, while semi-arid deserts are characterized by scrub brush and occasional trees.
Coniferous forests provide a home for spruce, fir, and pine across Canada and Europe. In tropical climates, evergreen rainforests feature tall palms and canopy trees that provide abundant shade below.
Deciduous forests dot much of the eastern United States, with beech trees often dominating the landscape. Mangroves thrive along coastal areas near tropical zones, while tundras in northern latitudes support mosses punctuated by low-growing shrubs.
What species of animals and plants inhabit each biome?
Tundra: The tundra is a frosty biome characterized by permafrost and low vegetation. Animals native to the tundra include caribou, musk oxen, Arctic foxes, snowshoe hares, and polar bears. Plants such as lichens, mosses, sedges, and shrubs grow in the tundra.
Desert: The desert biome is characterized by extreme temperatures and low rainfall. Animals that live in the desert include small mammals such as kangaroo rats, reptiles such as the sidewinder rattlesnake, and birds such as the roadrunner. Typical desert plants include cacti, succulents, and grasses.
Savanna: The savanna is a grassland characterized by a warm climate and alternating wet and dry seasons. Animals living in this biome include zebras, wildebeests, gazelles, lions, and hyenas. The savanna is also home to many species of grass, shrubs, and trees.
Mountains: The mountain biome is characterized by cold temperatures, high altitudes, and thin air. Animals native to the mountains include marmots, bighorn sheep, mountain goats, and ptarmigans. Both coniferous and deciduous trees grow in the mountains, as well as grasses, shrubs, and wildflowers.
Grasslands: Grasslands are characterized by vast stretches of grasses and a temperate climate. Animals found in this biome include bison, pronghorns, prairie dogs, and black-footed ferrets. Grasses, flowering plants, and shrubs are the primary vegetation in grasslands.
Rainforest: The tropical rainforest is characterized by a hot, humid climate and high levels of rainfall. Animals living in this biome include monkeys, sloths, parrots, toucans, and jaguars. Over half of the world’s plant species can be found in the rainforest, including tall trees, flowering plants, and vines.
Polar Regions: Polar regions are frigid biomes characterized by permafrost and low temperatures. Animals native to this region include polar bears, Arctic hares, Arctic foxes, and walruses. Plants found in this biome include mosses, lichens, and grasses.
Taiga: The taiga, also referred to as the boreal forest, is characterized by large coniferous trees and cold temperatures. Animals living in the taiga include moose, wolves, lynx, and snowshoe hares. Typical plants in this biome include pines, spruces, firs, and birches.
Temperate Deciduous Forest: The temperate deciduous forest is characterized by a mild climate and four distinct seasons. Animals native to this biome include bears, deer, chipmunks, and raccoons. Typical trees in this biome include oak, maple, and beech. Wildflowers and ferns are also present.
How does precipitation vary between biomes?
Precipitation varies widely between different biomes. Tropical rainforests are characterized by high annual rainfall ranging from 125 to 660 cm (50–200 in), with considerable seasonal variation.
The wet months in tropical rainforests may bring more than 30 cm (11–12 in) of precipitation, while the dry months may bring fewer than 10 cm (3.5 in). In contrast, deserts and chaparrals have very low levels of precipitation, with an annual rainfall of less than 25 cm (10 in).
Subtropical deserts and temperate grasslands have intermediate levels of precipitation, with annual rainfall levels of 25–125 cm (10–50 in). Boreal forests and Arctic tundra have higher levels of precipitation, with annual rainfall ranging from 100–200 cm (40–80 in).
Mountains and polar ice caps have very low temperatures, but they can receive large amounts of snow and ice depending on the season.
What factors influence the biodiversity of a biome?
Biodiversity is affected by a variety of factors, including climate, topography, latitude, humidity, precipitation, elevation, soils, rocks, and abiotic and biotic elements. The climate is perhaps the most important factor, as it determines the nature of any biome, but it is not the only one.
The climate is the general weather pattern of a region over time, which affects the plants and animals that can live in a particular biome. Biomes are divided into three main climate zones – tropical, temperate, and polar – each with its own distinct temperature and precipitation patterns.
Tropical zones get more direct sunlight and have hotter biomes, while temperate zones have colder winters and hotter summers, and polar zones have the coldest climates.
Topography also plays a role in influencing biodiversity, as it affects the amount of sunlight, water, and nutrients available to different species.
The type of soil also affects a biome, as different soils can provide different levels of fertility and groundwater availability. Latitude, humidity, and elevation all have an effect on a biome’s climate, which in turn affects the plants and animals that live there.
Abiotic and biotic elements also influence the biodiversity of a biome. Abiotic elements are non-living factors, such as relief, geology, and rocks, while biotic elements are living factors, such as plants and animals.
The plants and animals of any biome have unique adaptations that enable them to survive in such environments, creating a unique and diverse community of organisms.
What is the importance of preserving biomes?
Biomes are vital for maintaining the health and resilience of our planet. They offer a myriad of habitats that support biodiversity, provide us with oxygen, food, and natural resources, regulate the climate, and foster well-being.
From lush rainforests to vineyards and grasslands to coral reefs, each type of biome has its own unique set of biological features that need protecting. Without these ecosystems functioning properly, nature won’t function as it was intended to. Conservation requires conscientious stewardship and responsibility on our part.
It’s essential to make sure wildlife is respected and protected; sustainable farming practices are implemented; pollution—air, land, and water—is minimized; and renewable energy sources are embraced. Taking such proactive measures will help ensure that our biomes remain healthy for generations to come.
