Cerrado

Gustavo A.B. da Fonseca^{1, 2, 13}, Roberto Cavalcanti^{1, 15}, Anthony Rylands² and Adriano Paglia⁵

The Cerrado is the second largest of Brazil's major biomes (after Amazonia), originally covering some 2 031 990 km², and representing the most extensive woodland-savanna region in South America. It is entirely tropical, its core occupying the central Brazilian Plateau, although it extends also marginally into eastern Paraguay. Rainfall is typically high (between 1 100 and 1 600 mm annually), but is concentrated in a period of six to seven months (April to October), the dry season being pronounced and, in some places, resulting in water stress. Many of the typical Cerrado plant species are drought-adapted.

The Cerrado is a gradient-mosaic of different vegetation types, determined primarily by soil conditions. The only true forest formation is cerradão, a closed-canopy dry forest reaching 7 m in height on the more fertile soils. Cerrado sensu stricto is a woodland savanna with a well-developed herbaceous layer, small trees, shrubs, and trunkless palms, and the dominant vegetation occurs on widespread red and yellow latosols. Other formations include campo sujo (“dirty savanna”) and campo limpo (“clean savanna”), the former scrub grassland (sparsely distributed shrubs and short trees) and the latter, open grassland. Gallery forests are not classified as typical Cerrado formations, but are prevalent in the landscape, comprising an interconnected network of mesic habitats along the streams and rivers of three of the major Brazilian drainages. They are important for the maintenance of the diversity of the Cerrado fauna (Redford and Fonseca 1986), being a refuge and dispersal route for a significant number of plants and animals of Amazonian and Atlantic Forest origin (Sarmiento 1983).

Fire, both natural and human-induced, is an important feature of Cerrado ecology. The flora displays a number of adaptations to fire, including thick bark, leathery leaves, and a rapid regeneration capacity. Fire maintains the balance between grasses and woody vegetation; in its absence, trees predominate, resulting in dry forest. Seed germination is fire-dependent in a number of species.

The Cerrado is one of the richest of all tropical savanna regions and has high levels of endemism. Mendonça et al. (1997) listed 6 387 angiosperms, and total plant diversity is estimated at around 10 000 species, of which 4 400 are endemic. The herbaceous species are almost totally endemic. A conservative estimate for diversity of fungi (Dianese et al. 1997) gives 24 000 species, but, being based on six species per host plant, and considering only 4 000 vascular plant species, it is likely an underestimate. Several non-endemic plant species stand out as flagships for this hotspot: for example, the conspicuous palms Mauritia vinifera (locally known as buritís), which grow along the swampy headwaters of streams and rivers (known as veredas) that flow through the Cerrado's open grasslands. Trees of the genus Tabebuia (Bignoniaceae), known as ipê, are also spectacular and widespread inhabitants of the Cerrado; their brilliant yellow, pink, and purple flowers are a common sight.

Vertebrate diversity is also high in the Cerrado, but endemism low when compared to plants. Mammals are represented by 195 species, although only 14 are endemic. Four are representatives of the three endemic genera in the hotspot: a rodent (Microakodontomys transitorius), known only from a single specimen collected in 1986 in the Brasília National Park; the Candango mouse (Juscelinomys candango), a semi-fossorial rodent first discovered in 1960 on the site of the capital, Brasília, then under construction, and which has never again been collected; and the cerrado mouse (Thalpomys cerradensis) and hairy-eared cerrado mouse (T. lasiotis). The Cerrado is a major stronghold for a number of large, widespread South American mammals that are seen as flagships for the region: the maned wolf (Chrysocyon brachyurus), a large-eared, long-legged canid, 80 cm in height, which has long, golden-red fur and is one of the most attractive of all wild canids; giant anteater (Myrmecophaga tridactyla, VU); giant armadillo (Priodontes maximus, EN); Brazilian tapir (Tapirus terrestris, VU); pampas deer (Ozotoceros bezoarticus); and several cat species, including the jaguar (Panthera onca), puma (Puma concolor), ocelot (Leopardus pardalis), and jaguarundi (Puma yagouaroundi).

Bird diversity is relatively high in the Cerrado, with 605 species regularly recorded, 16 of these being strict endemics. Two of BirdLife International's Endemic Bird Areas (EBAs) coincide with the Cerrado Hotspot (Stattersfield et al. 1998). One well-known endemic flagship is the Brasília tapaculo (Scytalopus novacapitalis), a passerine with a very limited range, occurring in gallery forest remnants around Brasília, besides a few locations in Minas Gerais, including the Serra da Canastra National Park. Some of the larger birds are also good flagship species, particularly the rhea (Rhea americana).

There are 33 endemic reptiles (of a total of 225 species), six in the snake genus Apostolepis. As with the Atlantic Forest, the genus Amphisbaena is well represented, with at least 26 species present. Very little is known about the ecology of amphisbaenians, as they are largely subterranean. One species that has been well studied is the widespread giant worm lizard (A. alba), which can grow to 70 cm in length; feeds on beetles, ants, and spiders; and has a clutch size ranging from 8–16 eggs, one of the largest known for the family (Colli and Zamboni 1999). Among amphibians, some 289 species have been recorded, of which 26 are endemic, including two species endemic to Serra da Canastra National Park: the Canastra snouted tree frog (Scinax canastrensis) and Zagaia tree frog (Hyla sazimai).

Freshwater fish diversity is high, with approximately 800 species present, and an estimated 200 of these endemic. Generic diversity is also high, with some 240 genera represented in the hotspot, of which 18 are endemic. There is a paucity of information on invertebrates, but preliminary data on insect diversity indicates that 10 000 of the 40 000 species of Neotropical Lepidoptera, 129 of 443 Neotropical termites, and 139 of 547 Neotropical social wasps are found in the Cerrado (Raw 1998). Bees number at least 820 species (out of 7 000 for the entire Neotropics). Twenty-three of 64 tiger beetle species present are considered endemic (D. Pearson, pers. comm.).

The Cerrado has been occupied by humans for at least 11 000 years (Barbosa and Nascimento 1993), and perhaps as long as 30 000 (Schmitz 1993). Hunter-gatherer societies subsisted on game and native plants, as clearly indicated by the impressive Holocene rock paintings of animals found especially in the dry areas around the Rio São Francisco in Bahia and Minas Gerais and in Goiás and Piauí (Schmitz 1993). During the colonization of Brazil in the early 1500s, the Portuguese avoided the interior of the country because of treaties between Spain and Portugal, and also a cultural predisposition to settle near the sea (Holanda 1936). The first incursions, in search of gold and precious stones, were in the eighteenth century (Alho and Martins 1995), and opened the way for cattle-ranching, the primary economic activity until the mid-1950s, when the government began its plans for a new capital in Goiás, in the heart of the Cerrado, to stimulate the colonization and development of the region. Improved transport and infrastructure, a major commitment to the automobile industry, and agricultural and soil research over the ensuing years, resulted in the Cerrado becoming the major agribusiness (soybean, corn, and irrigated rice) frontier of the country. Following major failures in large-scale development programs in Amazonia, as of the 1970s the World Bank considered the Cerrado to be the alternative for Brazil's agricultural expansion (Goodland and Irwin 1975). Today, nearly one-quarter of all grain produced in Brazil comes from the Cerrado (Alho and Martins 1995).

Estimates of remaining natural vegetation indicate that the Cerrado has been heavily impacted. Mantovani and Pereira (1998) suggested that by 1993, approximately 67.1% was either “disturbed” and/or “highly modified,” with the remaining natural habitat largely fragmented. They detected only three areas of extensive undisturbed Cerrado (two in the far northeast and one in Mato Grosso do Sul); 37.3% of the Cerrado had already been totally converted to human use, and 41.4% was being used for pasture and charcoal production. Gallery forests have been particularly heavily impacted. These numbers indicate 78.7% under some form of human use, meaning that only 21.3%, or 432 814 km², is still in intact condition.

In spite of its large size and great importance for biodiversity conservation, the Cerrado is poorly represented in Brazil's protected area system. The World Database on Protected Areas indicates that only 1.4% is conserved in protected areas in IUCN categories I to IV, increasing to 5.5% when including other forms of reserves and parks. In Brazil, 62 strictly protected areas (state and federal parks, biological reserves, and ecological stations), mostly limited in size, cover 42 676 km²—only 2.1% of the hotspot's original extent. The most important parks include Chapada dos Guimarães (330 km²), Serra da Canastra (2 000 km², although only about 720 km² are currently protected), Emas (1 330 km²), and Grande Sertão Veredas (840 km²), and in 2001 a large and valuable area of the Cerrado in the State of Tocantins was secured as the Jalapão State Park (1 588 km²). Including protected areas of sustainable use (mainly Environmental Protection Areas), this number increases to 102 areas covering 83 520 km² or 4.1% of the Cerrado (Rylands et al. 2004).

Conservation International and its partners, the Fundaçao Emas, neighboring municipalities, and farming cooperatives have a major program under way for the protection and management of Emas National Park, probably the most important protected area in the entire hotspot, and threatened by surrounding agriculture, pesticides, and invasion of exotic grasses. The Brasíliabased Fundação Pró-Natureza-FUNATURA was responsible for the creation in 1989 of the Grande Sertão Veredas National Park, protecting a significant sample of the Gerais ecosystems: native grasslands, veredas (Mauritia palm-dominated bogs), and scrub forests, in addition to populations of key Cerrado vertebrates.

The Brazilian Government held an expert-based Regional Priority Setting Workshop for the Cerrado and Pantanal in 1998 (Fundação Pró-Natureza-FUNATURA et al. 2000). Seventy priority areas for conservation were identified, ranging from the central highlands of the country, at the headwaters of Brazil's major rivers, through the savannas of Amazonia, to the Pantanal of southwestern Brazil, down to fragmented Cerrado remnants in the states of São Paulo and Paraná. The meeting concluded with recommendations for immediate action, with suggestions for changes in legislation in order to create incentives to preserve biodiversity together with water sources, consolidate existing parks and reserves, establish new protected areas, and more intensively survey this vast region that is still so little known to science.

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