A biome is a region of the Earth’s surface that shares similarities in climate, flora, and fauna , constituting zones identifiable by the predominant ecosystems within them. Also known as biotic areas or bioclimatic landscapes .
In this way, taking into account their basic and determining characteristics, such as latitude , temperature , height, soil and precipitation, it is possible to trace different regions on the Earth’s surface, taking into account the complex relationships between soil, vegetation and fauna to define each one separately.
The same biome can have different local names , but still fall into the same biogeographical category. Furthermore, the term biome should not be confused with other terms such as ecozone , habitat , or ecoregion .
The number of biomes in the world is finite and covers all known locations to date, namely:
- 14 terrestrial biomes
- 12 freshwater biomes
- 5 marine biomes
It may be useful to you:
- Plain
- Rainforest
Examples of biome
- Steppe. A biome with low rainfall, flat terrain, and herbaceous vegetation, it is usually found far from the sea, in regions with wide temperature variation and soils rich in minerals but lacking in organic matter . It is often considered a cold desert, as opposed to torrid deserts, although they usually occupy smaller areas, such as the steppes of Asia, North America, and Argentine Patagonia, or the high plateau of the Andean Puna.
- Desert. A predominantly arid biome with little rainfall and little vegetation, although the flora and fauna tend to adapt to the harsh living conditions. There are hot deserts, such as the one that covers northern Africa (the Sahara), or frozen or polar deserts, such as the Antarctic Ice Plateau, whose cold climate prevents the formation of rain. Sandy, rocky, and frozen deserts can also be found. This is a vast biome, covering almost a third of the planet: 50 million square kilometers, of which 53% are warm and the rest are cold.
- Tundra. Characterized by its low temperatures and frozen ground, the tundra is a low vegetation biome typical of polar regions, occupying one-fifth of the planet’s surface. With a significant presence of mosses, lichens, and marshy soil, abundant in peat bogs , the tundra is common in Siberia, Alaska, Canada, and Greenland in the northern hemisphere, and the southernmost parts of Chile and Argentina, as well as the sub-Antarctic islands near sea level in the other hemisphere. These biomes are close to the polar circles and therefore tend to have cold climates and short summers, with maximum temperatures not exceeding 10 °C. Permafrost (ground freezing) can often occur.
- Grassland. This biome includes temperate grasslands and shrublands, located in areas with very low rainfall (300 to 1,500 mm per year) to support forests , but sufficient to avoid being considered desert areas. Its fertile, multi-layered soil and abundant organic matter, a product of the short life cycle of the vegetation, are ideal for growing corn, wheat, and other food plants. Its cold winters and warm summers are typical of North America or the Argentine Pampas, as well as the South African Veld or the Australian savanna.
- Chaparral. Known as the Mediterranean forest , it is characteristic of regions with a mild climate, with more or less abundant rainfall in winter and hot, dry summers where there is a risk of fire. These are typical biomes of the Mediterranean region, California and the northwestern Mexican coast, as well as Chile and Australia. They do not usually have a very high animal biodiversity , although in the case of Europe, the biodiversity of migratory birds is high. This does not mean it is an uninhabited biome: it is usually home to large numbers of insects , lizards, and rodents.
- Taiga. Also known as the boreal forest , the taiga is the largest expanse of forest on the planet. Its vegetation is almost exclusively composed of tall, evergreen conifers, such as firs, maples, and pines, and is home to abundant herbivorous fauna . Geographically, they are exclusive to the Northern Hemisphere, occurring in Siberia and European Russia, as well as Alaska and Canada, where they are bordered by the steppe to the south and the tundra to the north.
- Tropical rainforest. Occupying large regions near the equator, in South America (the Amazon) and Africa (the Congo Rainforest), Asia, and Oceania, it is the biome with the greatest abundance and biomass on the planet. Its lush, high-altitude vegetation and abundant canopy guarantee fertile, moist soil, thanks also to the frequent and abundant annual rainfall and the warm climate with no winter. Rainforests are the world’s great reservoir of biodiversity (50% of known species) despite occupying less than 7% of the Earth’s surface.
- Savanna. This is usually the name given to areas in transition between jungles and semi-deserts, as they combine characteristics of forest and grassland. They are found in tropical and subtropical areas with dry climates, such as the Serengeti in Tanzania or the Colombian-Venezuelan plains. Savanna vegetation is shrubby or herbaceous, and its climate is warm and pleasant, between 20 and 30°C.
- Mangroves. These biomes, formed in intertidal zones (near the sea) in tropical and intertropical latitudes, are characterized by the abundant presence of saline-tolerant trees (usually mangroves), as well as a diverse and abundant coastal fauna. They are typical habitats for amphibians and waters with abundant organic matter, such as marshes and estuaries, with soft bottoms of sand, silt, or clay.
- Deciduous forest. A rare biome in the world, it is a temperate forest of deciduous trees adapted to the duality of a cold, dry winter climate and a hot, humid summer, such as fir and elm. It is also known as a temperate broadleaf forest and can be found in the Northern Hemisphere in humid continental areas of Japan, Korea, Canada, Russia, and the United States.
- Wetland. This term refers to areas of extremely high humidity, generally flat, with a generally flooded surface and low oxygen content, a mixture of aquatic and terrestrial ecosystems: swamps, marshes, peat bogs, as well as, depending on the classification, mangroves and estuaries of rivers or seas . These areas rich in decomposing organic matter contain hydrophytic vegetation, amphibian fauna, and abundant endemic species.
- Oceans. The oceanic biome comprises all seas and oceans, as well as their coastal zones, which are distinguished by their water depth. These are areas of enormous biodiversity, predominantly coastal, reef, and deep-sea, as well as abyssopelagic: adapted to the dark zones and enormous pressure of the seabed. Marine flora is restricted to phytoplankton, algae, and other minor plant forms.
- Freshwaters. This group includes large rivers and lakes, as well as the frozen waters of the poles, which have a lower salt content and are distinguished from the oceanic biome. They are abundant in amphibian and reptile species , birds and insects adapted to aquatic life, as well as freshwater fish and mixed vegetation, algae and lilies. The polar case is an exception, since life subject to polar aridity is restricted to endemic species and certain forms of moss and resistant vegetation.
- Anthropogenic biomes. Perhaps the most complicated biogeographic category, as it aims to capture the areas where humans have left their mark and adapted the climate, soil, vegetation, and fauna to their whim, both directly and indirectly. Cities and urban landscapes would fall under this category , but it is a category that needs to be discussed.
- Oases. Found within the hot desert biome, these are spaces with abundant water and vegetation, and therefore wildlife, emerging from the sandbanks. Many of them are home to human settlements and even crops, such as those in the Sahara, the Arabian Peninsula, or Parras de la Fuente in Mexico.