What is a biome?

We explain what a biome is and what types of biomes exist. In addition, examples of biomes: desert, steppe, tundra, jungle and more.

1. What is a biome?

By biome, biotic area or bioclimatic landscape is called a region of the Earth’s surface that presents uniformities in terms of climate, flora and fauna , thus constituting an identifiable area from the type and variety of ecosystems that is possible find in it.

The same biome, then, may have different local names, but it is always considered the same biogeographic category, with stable ecological characteristics . This term should not be confused with others such as ecozone , habitat or ecoregions .

Thus, and taking into account basic and determining characteristics, such as height, latitude, temperature, soil types and precipitation range, the set of biomes present on the earth’s surface can be traced, paying attention to the relationships between soils , vegetation and fauna , to define each one separately. This is a particularly important classification task for biologists , ecologists and conservationists.

The number of biomes in the world is finite, and covers all known places to date. According to WWF, there are 14 terrestrial biomes, 14 freshwater biomes and 7 marine biomes .

2. Types of biome

Biomes are classified according to different systems, but the most used are those of WWF, Holdridge, Whittaker, Walter and Bailey. Each system is based on its own rules, taking into account the physical, geographical, climatic and biotic conditions that concern each region. Thus, one can speak of:

• Terrestrial biomes . Those that take place on the mainland, that is, somewhere on the continental shelf, whether in plains, mountains or deserts of any nature.
• Marine biomes . Those found in salt water deposits: seas and oceans , as well as continental coasts.
• Freshwater biomes . Those that take place in lakes, rivers and other freshwater deposits, as well as their respective coasts.

3. Biome Examples

• Desert . A predominantly arid biome, with little rainfall and xerophytic vegetation, if any. There are warm ones, such as the one that covers the northern part of Africa (Sahara desert) and frozen or polar, like the frozen plateau of Antarctica, so cold that liquid water is nonexistent. They also usually occur on sandy, rocky and icy soils. Almost a third of the planet is covered by this type of biome: 50 million square kilometers (53% warm and the rest cold).
• Estepa . Low rainfall biome, of flat territory and herbaceous vegetation (shrubs and weeds at most) that is usually far from the sea. They have a wide thermal variation and soils rich in minerals, but scarce in organic matter and therefore not very fertile. It can be considered a wasteland, that is, a cold and rocky desert, such as the steppes of Asia, North America and the Argentine Patagonia, or the high plateau plateau of the Andean Puna.
• Tundra . Low temperature biome and icy soils, low vegetation typical of polar areas, occupies almost a fifth of the total surface of the planet. Mosses, lichens and swampy soils predominate, abundant in peat bogs . It is common in Siberia, Alaska, Canada and Greenland, as well as in the southern extremes of Chile and Argentina, regions with cold climates andshort summer , whose maximum temperatures do not exceed 10 ° C. Sometimes freezing of the soil ( permafrost )may occur.
• Taiga . Called a boreal forest at the same time, this biome is the largest forest reserve on the planet, composed almost exclusively of conifers of large size and evergreen, such as firs, maples and pines, and abundant herbivorous fauna. They are exclusive to the northern hemisphere: Siberia and European Russia, Alaska and Canada.
• Meadow . Predominant biome of grasslands and temperate thickets, in areas of low rainfall (around 300 to 1500mm per year), unable to house forests , but without becoming desert areas. Its soil is fertile and abundant layers, product of the short life of vegetation. Ideal for the cultivation of food plants, with cold winters and hot summers, typical of the North American areas or the Argentine Pampas.
• Rainforest . This biome extends in the vicinity of the equator, in South America (the Amazon), in Africa (theCongo jungle ), in Asia and Oceania. It is the most abundant in biomass on the planet: a high and lush vegetation with an abundant crown, which guarantees a fertile and moist soil, with very frequent and abundant annual rainfall and a warm climate, devoid of winter. They are the great biodiversity reservoir ofthe planet (50% of all known species) in a strip less than 7% of the earth’s surface.