The IBGE launches the experimental geoscientific investigation Terrestrial Natural Regions and Domains of Brazilian Biomes, which shows an unprecedented proposal for the natural regionalization of the national territory. The study will be presented at an event at Casa Brasil IBGE COP-30, in Belém, on November 27, at 9 am, and will be broadcast live on YouTube.

Different from traditional political-administrative limits, such as states and municipalities, this approach considers ecological and environmental criteria to more accurately represent the diversity of Brazilian biomes and support the production of environmental, social and economic statistics. The study, which includes ocean islands, reveals the natural diversity of Brazilian biomes, expressed in 52 natural domains (large areas with similar physical-biotic characteristics), and 271 natural regions (more detailed subdivisions within these domains).

Of the 52 domains, 43 are in continental areas, eight in the coastal system and one covers all ocean islands. Among the 271 regions, 246 occur in the interior of the continent, 19 in coastal areas and 6 on islands. In the continental interior, 183 regions correspond to the core areas of the domains and 63 are located in transition zones, generally between different biomes.

Number of Natural Regions and Domains, total, in the continental interior,
in the Coastal System and Ocean Islands, according to Biomes

Database and relevance

The mapping was produced from continuous geospatial databases in Brazil, stored in the IBGE's Environmental Information Database (BDiA), complemented by climate and hydrographic information. The study sought to represent the original natural picture of the landscapes, even where the vegetation cover is altered by human actions. In these areas, a reconstruction of the natural condition was made based on the vegetation classification.

The proposed regionalization has the potential to support public policies and surveys in several areas, such as the production of environmental, social and economic statistics; natural capital accounting, with an emphasis on ecosystems; support for the creation and redefinition of conservation units and geoparks; in addition to serving as a reference for environmental management and biodiversity studies, including the identification of endemic areas of flora and fauna.

Diversity between biomes

The physical and phytophysiognomic particularities of each biome guided the identification and delimitation of natural regions and domains. In the Amazônia and Mata Atlântica biomes, which are predominantly forested, there are phytophysiognomic diversifications that shelter different geological, geomorphological and pedological features. The natural domains and natural regions of these forest biomes differ both by physical and biotic characteristics (phytophysiognomic characteristics).

In the Caatinga, Cerrado, Pantanal and Pampa biomes, which are of rural or savanna nature, differentiation occurs mainly due to geodiversity. The IBGE researcher Pedro Edson Leal Bezerra explains that Brazilian biomes do not have a uniform composition:

“Every study of biomes shows that Brazilian biomes are not homogeneous; they have a predominant characteristic. Let's say, the Amazônia is typically forested, as is the Mata Atlântica. We identified 97 natural regions in the Brazilian Amazon, which are grouped into 16 natural domains. These domains are defined by differences in vegetation typology. This same forest extends from the sedimentary basins to shield areas, which also show differences in relief and soils. Within each domain, there are small variations related to relief and geology. The concept of domain groups one or more natural regions,” highlights Bezerra.

Amazônia Biome

The Amazônia Biome has 16 natural domains, 15 of which are continental and one coastal, and 97 natural regions. It houses Dense and Open Ombrophylous Forests, as well as Evergreen and Semideciduous Seasonal Forests, distributed over highlands and depressions of the Guyana Shields, Central Brazil and the Amazon, Solimões and Parecis basins, as well as in the Tablelands and Lowered Plateaus of the Alter do Chão and Grajaú basins, on different types of soils, such as Oxisols and Argisols. Also noteworthy are the Campinaranas on quaternary sediments of the Içá Basin and the Savannas and Steppe-Savannas of the Northern Amazon, in the Boa Vista basins and slopes of Mount Roraima. The Amazon coastal system extends from the Oiapoque River to the Golfão Maranhense, covering the mouth of the Amazon, the island of Marajó and the extensive mangroves of Pará and Maranhão.

Mata Atlântica Biome

The Mata Atlântica Biome gathers ten natural domains, being six continental and four coastal, and 57 natural regions. Semideciduous Seasonal Forests cover the Atlantic Shield and the highlands of Minas Gerais and Bahia, while Dense Ombrophylous Forests are distributed close to the coast on the coastal tablelands of the Northeast, extending to Serra do Mar in the Southeast. The Araucaria Forests predominate in the basaltic highlands of the South, and the steppes appear in Campos Gerais. The coastal system extends from Rio Grande do Norte to Santa Catarina, reflecting the variation in relief and climate. It includes dunes, cliffs, reefs, deltas and lagoons, with emphasis on the Paranaguá and Ribeira do Iguape estuaries, in addition to the lagoon plains in the south of Santa Catarina down to the limit with the Pampa Biome.

Country and savanna biomes

The Caatinga, the Cerrado and the Pantanal, which form the so-called Seasonal Dry Diagonal of South America, in addition to the Pampa, have a predominance of open vegetation, with localized variations of humid forests.

The Caatinga, with eight domains and 35 natural regions, is dominated by Steppe-Savanna, which covers shallow and stony soils of the sertaneja depressions, highlands and pre-coastal tablelands. It has transition areas with the Mata Atlântica and the Cerrado and exceptional humid landscapes in Diamantina and Araripe Chapadas. The semi-arid coastal system stands out for its dunes and deltas, as on the coast of Ceará and Rio Grande do Norte.

The Cerrado is characterized by Savanna on reliefs created in rocks from the Atlantic Shield and on sedimentary basins, covering extensive areas of Goiás, Minas Gerais, Mato Grosso and Mato Grosso do Sul. It includes the Central Highland, Veadeiros, Parnaíba, Guimarães, Gerais and Parecis Chapadas, the Canastra Mountain and the Southern Highlands, in addition to alluvial plains such as Bananal Island. The coastal system is home to the Lençóis Maranhenses and the Parnaíba Delta.

The Pantanal is formed in the alluvial fan plains of the Mato Grosso Pantanal, with a predominance of Savanna and areas of contact with Seasonal Forests and Steppe-Savanna, pointing to the transition to the Chaco Biome.

The Pampa is covered by Steppes on rocks of the Paraná Basin and comprises the Central Depression, bordered to the west by the Campanha and Missões highlands. To the west, the steppes extend over the residual highlands of the Rio Grande do Sul Shield. The coastal system shows the broad Lagoon Plain of the Patos and Mirim lagoons, with dunes and sandbanks.