In this post, we'll unravel the concept of a biome, explore Brazil's main biomes, learn about their unique geographical characteristics, discover the incredible diversity of flora and fauna, understand how people live in these environments and, above all, why environmental preservation is so vital. Get ready for a fascinating journey through the universe of Brazilian biomes and discover why they are fundamental to the balance of our planet!
What are biomes?
The term biome was coined in 1943 by American ecologist Alfred Russel Wallace, derived from the Greek words "bio" (life) and "oma" (group or mass). A biome refers to a group of phytogeographic formations - plant communities that occupy the same geographical area. Expanding this definition, biomes can also be understood as biological communities where living beings interact, forming distinct ecosystems. Depending on climatic conditions, each biome has a distinctive type of vegetation which, in turn, attracts specific fauna.
A biome is an area of geographical space, with dimensions of up to more than one million square kilometers, whose characteristics are the uniformity of a defined macroclimate, a certain phytophysiognomy or plant formation, a fauna and other associated living organisms, and other environmental conditions, such as altitude, soil, flooding, fire, salinity, among others. All these characteristics give it a peculiar structure and functionality, its own ecology (COUTINHO, 2006).
Brazil is a veritable mosaic of biomes, each with its own geographical, climatic and biological particularities. Let's get to know some of them:
1. Amazon Rainforest
The Amazon Rainforest is Brazil's largest biome, covering around 49% of the country'sterritory and representing 5% of the planet's land surface. In addition to Brazil, the Amazon extends to eight other South American countries: Venezuela, Colombia, Peru, Bolivia, Ecuador, Guyana, Suriname and French Guiana (overseas territory of France). Its relief is predominantly lowland, with plateaus, plains and depressions formed over millions of years by geological and climatic processes. The formation of the Andes Mountains approximately 80 million years ago was crucial to the current configuration of the riverbeds, especially the Amazon River, which has become the backbone of this vast biome.
Located close to the equator, the Amazon has a hot and humid equatorial climate throughout the year. Average monthly temperatures vary between 24°C and 27°C, and the region receives a high rainfall of up to 4,000 mm per year. Rainfall is well distributed, with very short dry spells - an essential condition for maintaining the dense forests and rich biodiversity of the Amazon, which extends to all the countries mentioned. The Amazon River, the region's main hydrographic system, is responsible for around 20% of the world's fresh water volume. Its numerous tributaries, such as the Negro, Madeira and Tocantins, guarantee a double period of annual flooding, which is fundamental for navigation and the maintenance of aquatic ecosystems.
Curiously, despite being home to an enormous variety of life, Amazonian soils are generally poor in nutrients, with only a surface layer rich in organic matter. Only around 8% of the Amazon's territory has naturally more fertile soils, such as the floodplains, which are enriched by the periodic floods that deposit nutrients in the riverbeds. This phenomenon contributes to the exuberance of the vegetation in certain areas throughout the Amazon region, regardless of national borders.
The Amazon is considered to be the world's largest biodiversity reserve, home to thousands of species of plants and animals - many of which have not yet been catalogued. The flora is predominantly broad-leaved, dense and hygrophilous, while the fauna is mostly arboreal, with species adapted to living in the treetops. The density of the canopies prevents light from entering the understory, limiting ground vegetation and, consequently, the presence of terrestrial animals. Among the typical inhabitants of the Amazon fauna are parrots, toucans, monkeys and marsupials, as well as an impressive diversity of insects and other invertebrates, distributed throughout all the countries that share this exuberant biome.
2. Caatinga
The Caatinga is a unique biome, located predominantly in the Northeast region, covering around 10% of the national territory. It extends over the states of Ceará, Rio Grande do Norte, Paraíba, Pernambuco, Alagoas, Sergipe, Bahia, Piauí and part of Minas Gerais. The relief is marked by interplanaltic depressions and residual mountain ranges, such as the Araripe and Boroborema ranges, which are the result of geological and erosion processes that have shaped the landscape over millions of years.
The semi-arid climate is characterized by high average annual temperatures of between 24°C and 26°C and low rainfall, ranging from 250 mm to 800 mm per year. Rainfall is irregular and poorly distributed throughout the year, concentrated in short periods and causing long periods of drought. The soils are generally shallow, stony and, in some areas, saline. Despite this, they contain minerals that can favor agriculture, although the lack of water represents a significant challenge for agricultural activity in the region.
The vegetation of the Caatinga is adapted to arid conditions, mainly composed of xerophytic species that resist drought. Plants include cacti (mandacaru, xique-xique), bromeliads, succulents and small trees with deciduous leaves, which lose their leaves during droughts to reduce water loss. Many plants have deep roots to reach groundwater and succulent stems to store water. Biodiversity is rich, with several endemic species of flora and fauna, including animals such as the white-wingedmagpie, the mountain mar moset and the ball armadillo, which are adapted to the semi-arid environment.
The hydrography of the Caatinga is characterized by intermittent rivers, which only flow during the rainy season. The main perennial river that crosses the biome is the São Francisco River, which is essential for water supply and irrigation in the region. Water scarcity is a constant challenge, leading to the construction of dams and reservoirs to store water. Conservation of the Caatinga is crucial, as the biome faces threats such as deforestation, desertification and loss of biodiversity due to inadequate agricultural practices and climate change. Conservation efforts are essential to maintain the ecological balance and livelihoods of local communities that depend on the Caatinga's natural resources.
3. Cerrado
The Cerrado is the second largest biome in South America, covering an area of 2,036,448 km² - around 22% of Brazil's territory. It extends over several states, including Goiás, Tocantins, MatoGrosso, Mato Grosso do Sul, Minas Gerais, Bahia, Maranhão, Piauí, Rondônia, Paraná, São Paulo and the Federal District, with enclaves in Amapá, Roraima and Amazonas. Characterized by soils poor in mineral salts, the Cerrado has vegetation adapted to these conditions, with plants with twisted stems and thick bark that are resistant to the harsh environment. The climate is semi-humid, alternating between dry and rainy seasons.
The flora of the Cerrado includes typical species such as sucupira, pequi, copaíba, angico, caviúna, jatobá, lobeira and cagaita. These plants have developed adaptations to survive the acidic soils and frequent natural fires. The fauna is equally diverse, and is home to animals such as the sabiá-do-campo, tatu-canastra, tamanduá-bandeira, lobo-guará, fox-do-campo and veado-campeiro. This biological wealth makes the Cerrado the most biodiverse savannah in the world.
Recognized as a global biodiversity hotspot, the Cerrado is home to numerous endemic species, but is facing significant habitat loss. It is home to 11,627 species of native plants, with notable variation between different phytophysiognomies. Its fauna includes around 199 species of mammals, 837 of birds, 1,200 of fish, 180 of reptiles and 150 of amphibians, many of which are endemic. Recent estimates indicate that the biome is a refuge for 13% of butterflies, 35% of bees and 23% of termites in the tropics.
In addition to its environmental importance, the Cerrado has great social relevance. Various communities depend on its natural resources, including indigenous ethnic groups, quilombolas, geraizeiros, riparians, babaçueiras and vazanteiros. These populations have traditional knowledge about local biodiversity, using more than 220 species for medicinal purposes and another 416 species for recovering degraded soils, protecting against erosion and biological pest control. Fruits such as pequi, buriti, mangaba, cagaita, bacupari, cajuzinho do cerrado, araticum and baru seeds are regularly consumed and sold. However, the Cerrado faces serious threats, such as species extinction. It is estimated that 20% of native and endemic species no longer occur in protected areas, and at least 137 animal species are threatened with extinction. Agricultural expansion, predatory exploitation for charcoal production and the scarcity of protected areas - only 2.85% of the biome - highlight the urgency of conservation.
4. Atlantic Forest
The Atlantic Forest is a biome that originally occupied more than 1.3 million km², stretching from Rio Grande do Norte to Rio Grande do Sul, along the Brazilian coast, covering 17 states of the country. It occupies approximately 13% of the Brazilian territory and is home to more than 50% of the Brazilian population. Due to intense human occupation and activities such as deforestation for agriculture, urbanization and the exploitation of natural resources, only around 27% of its original forest cover remains, often in fragmented areas that are difficult to access. This biome is considered one of the most threatened in Brazil and has been identified as the fifth richest area in endemic species and the most threatened in the world.
The predominant climate in the Atlantic Rainforest is humid tropical, with mild temperatures and abundant rainfall of up to 2,500 mm per year. This high rainfall, combined with the maritime influence, favors the formation of dense, lush forests. The relief is varied, including coastal plains, mountain ranges and plateaus, which contributes to the diversity of microclimates and habitats. The soils are generally fertile, which historically encouraged human occupation and agriculture in the region.
The vegetation is made up of different forest formations, such as the Dense Ombrophilous Forest, influenced by oceanic humidity; the Semideciduous SeasonalForest, where some species lose their leaves during the dry season; and the Mixed Ombrophilous Forest, known as the AraucariaForest. It also includes associated ecosystems such as mangroves, restingas, highlandfields and inland marshes. Emblematic species of flora include brazilwood, jacarandá, peroba, ipê and jequitibá, as well as mosses, ferns and orchids.
The Atlantic Forest is one of the most biodiverse biomes on the planet, home to around 20,000 plant species, which represents approximately 35% of the species found in Brazil. In terms of fauna, there are an estimated 261 species of mammals, 620 birds, 200 reptiles, 280 amphibians and 350 fish, with a high level of endemism. Animals such as marmosets, anteaters, ocelots, toucans, arapongas, boa constrictors and jararacas are some of the representatives of the rich local fauna. The hydrography is marked by perennial rivers that rise in the mountains and plateaus, playing a crucial role in supplying water to more than 70% of the Brazilian population living in this region.
5. Pampas
The Pampa Biome, also known as Campos Sulinos, is located in the far south of Brazil, covering approximately 2% of the national territory. Restricted to the state of Rio Grande do Sul, it occupies around 63% of the state's area and extends beyond Brazil's borders, joining the pampas of Argentina and Uruguay. The territory is characterized by vast plains, gentle hills called coxilhas and formations such as the Campanha Plateau and the Central Depression, resulting in a unique landscape of open fields.
The climate of the Pampa is predominantly humid subtropical, with rainfall well distributed throughout the year and no defined dry season. Temperatures vary according to the seasons, with hot summers and cold winters, with occurrences of freezing temperatures. This climatic variation directly influences the region's vegetation and biological cycles. The soils are generally deep and fertile, favoring the growth of natural pastures and the practice of agriculture, especially rice cultivation and extensive livestock farming.Pampa in Rio Grande do Sul, which offers suitable conditions for grazing, and livestock farming is widely practiced. Due to the intense cattle farming, the soil is eroding, starting a process of desertification.
The biome's vegetation is dominated by natural grasslands, made up of a rich diversity of grasses, herbs and shrubs adapted to the local climate. It is estimated that there are more than 3,000 plant species, including a remarkable variety of native grasses and legumes. Forest formations are less common, occurring mainly in riparian areas along watercourses. The biodiversity of the Pampa is significant, home to almost 500 species of birds, such as the rhea, the joão-de-barro and the pica-pau-do-campo, as well as more than 100 species of mammals, including the deer, the graxaim and the armadillo-mulita.
In terms of hydrography, the Pampa is crossed by several rivers and streams that form part of the Uruguay and Jacuí river basins. These hydrographic networks are essential for maintaining local ecosystems, providing water for fauna, flora and human activities. Despite its ecological and cultural importance, the Pampa Biome faces significant environmental challenges, such as the expansion of intensive agriculture, the replacement of native pastures with exotic crops and habitat fragmentation. The conservation of this biome is essential to preserve its rich biodiversity, its ecosystem services and the cultural heritage associated with gaucho traditions.
6. Pantanal
The Pantanal Biome is recognized as the largest continuous floodplain on the planet, occupying approximately 150,355 km², which corresponds to around 1.76% of the national territory. It is located in the states of Mato Grosso and Mato Grosso do Sul, and also extends into parts of Bolivia and Paraguay. Inserted in the Upper Paraguay river basin, the Pantanal is a sedimentary plain influenced by rivers that overflow periodically, creating a unique ecosystem of wetlands and terrestrial areas that vary according to the seasons. This characteristic makes it the largest continuous floodplain on Planet Earth, and is the main factor in its formation and differentiation from other biomes.
The climate of the Pantanal is tropical continental, with two well-defined seasons: the rainy season, from November to March, and the dry season, from April to October. The average annual temperature varies between 24°C and 26°C, with extremes of 0°C to 40°C. The average annual rainfall is around 1,000 to 1,400 mm. These climatic characteristics, combined with the flat terrain, contribute to the flood cycles that define the rhythm of life in the region, directly influencing the local flora and fauna.
The Pantanal's vegetation is extremely diverse, the result of the confluence of different biomes: Amazon, Cerrado, Atlantic Forest and Chaco. It ranges from dense forests to open fields and areas of aquatic vegetation. Typical species include piúva, ipês, jatobás, buritis and a wide variety of grasses and aquatic plants. The soils are mostly alluvial, formed by sediments deposited by river floods, which makes them rich in nutrients and favorable for the development of vegetation.
The Pantanal's biodiversity is remarkable, housing a rich fauna with more than 263 species of fish, 41 of amphibians, 113 of reptiles, 463 of birds and 132 of mammals. Threatened species include the jaguar, the tuiuiú (the Pantanal's symbol bird), the giant otter and the marsh caiman. The hydrography is dominated by the Paraguay River and its tributaries, which are responsible for the seasonal floods that renew the soil's nutrients and sustain the biome's complex web of life. These periodic floods create a mosaic of aquatic and terrestrial habitats, essential for the reproduction and feeding of various species.
Despite being considered Brazil's best preserved biome, the Pantanal faces challenges such as the expansion of agriculture, deforestation, fires and river pollution, which threaten its ecological integrity. The predominant economic activities are extensive cattle ranching, which has been practiced for more than two centuries, and ecological tourism, which has gained prominence due to its scenic beauty and the opportunity to observe wildlife. The conservation of the Pantanal is crucial not only for Brazil, but for the global environmental balance, given its role in climate regulation, biodiversity conservation and the maintenance of water resources.
The Importance of Preserving Biomes
Preserving biomes is essential not only to maintain biodiversity, but also to guarantee vital ecosystem services such as climate regulation, the maintenance of water cycles and soil protection. The destruction of these environments leads to the loss of species, climate imbalance and negative impacts on human health.
Brazil's biomes are true natural treasures, home to an immense diversity of life and playing crucial roles in the global ecological balance. Understanding their characteristics and recognizing the threats they face are fundamental steps towards their preservation. It is the collective responsibility - of governments, communities and individuals - to adopt sustainable practices that ensure the conservation of these vital environments for future generations. Let's join forces to take care of these natural treasures, ensuring that they continue to flourish for generations to come!
References
- BRAZIL. Ministry of the Environment. National Register of Conservation Units - CNUC, 2010. Available at: http://www.mma.gov.br/areas-protegidas/cadastro-nacional-de-ucs.
- COUTINHO, Leopoldo Magno. Brazilian Biomes. São Paulo, Oficina de Textos, 2016.
- IBGE. Biomes and Coastal-Marine System of Brazil( 2023) Available at: https://www.ibge.gov.br/geociencias/cartas-e-mapas/informacoes-ambientais/15842-biomas.html?edicao=25799&t=acesso-ao-produto
- IBGE. Map of Biomes and Vegetation. 2004. Available at: http://www.ibge.gov.br/home/presidencia/noticias/21052004biomashtml.shtm
- NASCIMENTO, Diego Tarley Ferreira. Brazilian biomes and the defense of life. Goiânia, Kelps, 2017.