Location and General Description
Heterogeneity is the best word to describe the Bahia interior forests. This ecoregion covers a large area, including the Brazilian states of Sergipe, Bahia, Minas Gerais, Espírito Santo, and Rio de Janeiro. It is bordered by the ecoregions of Bahia coastal forest (east), Cerrado (west), Caatinga (north) and Paraná-Parnaíba (south). Although the dominant vegetation in this ecoregion is a kind of seasonal forest, at least five other types of vegetation have been reported for it, ranging from rocky savannas ("campos rupestres") to evergreen forests. The ecoregion encompasses several different geological substrates (Tertiary-Quaternary to Pre-Cambrian) and several types of geomorphological units (ranging from young depressions to old crystalline plateaus). Climate is also variable, and several climatic types can be identified. In general, the dominant climate is tropical, semi-humid, with 3 to 5 dry months and mesothermic characteristic (Nimer, 1979). Average annual rainfall varies between 1,000 and 1,750 mm, and average annual temperature between 18° and 22oC (Nimer, 1979). Seasonal forests can be semi-deciduous or deciduous. Seasonal semi-deciduous forests cover most of the ecoregion. They are well developed (18 to 30 m tall), stratified and with a representative number of trees of large size. These forests vary according to the number of epiphytes and whether or not there are bamboos and graminoids in the herbaceous strata. Important species are Luehea grandiflora, Cariniana estrellensis, Virola gardneri, Nectandra reticulata, Joanesia princeps, and the highly threatened "Brazilian rosewood" (Dalbergia nigra). Euterpe edulis, regionally known as "palmito" is a frequent palm in some forest remnants. Seasonal deciduous forests are more restricted in distribution, occurring mostly on southern Bahia (Rio Pardo drainage) and the northern Minas Gerais on eutrophic soils derived from limestone rocks. Deciduous forests are lower (18 to 25 m tall) and dense, with high density of large terrestrial and arboreal bromeliads. They are locally known as "vine forests" ("mata de cipó"). Important trees are of the genera Cavanillesia, Cedrella, Parapiptadenia, and Piptadenia (Veloso et al., 1991).
Bahia interior forests are still poorly-known. However, ranges of some range-restricted species indicate that they are composed of several distinct biogeographic units. The almost unexplored seasonal forests in Sergipe are home to a recently described endemic primate species (Coimbra’s titi monkey Callicebus coimbrae), indicating that other endemic species of different groups of organisms will probably be found there as well. The seasonal deciduous forest is a well-known center of endemism for birds (Sick, 1993), harboring two very specialized species of antbirds (slender antbird Rhophornis ardesiaca and narrow-billed antbird Formicivora iheringi). In contrast, the biota of the seasonal semi-deciduous forests of Minas Gerais, Espírito Santo, and Rio de Janeiro seems to be a subset of the biota found in the Serra do Mar ecoregion. Therefore, the main biodiversity feature of the Bahia Interior Forests is the mixture of biotas that share very little evolutionary history.
Bahia interior forest is one of the most modified ecoregions in Atlantic forest region. There are few large remnants of forests (of more than 10 km2), and even these are currently under strong pressure from anthropogenic activities. Less than 1 percent of this ecoregion is officially protected as reserves or parks. The most representative park of this ecoregion is the State Park of Rio Doce, which is composed of 359 km2 located on the middle valley of the Rio Doce, with areas in the districts of Marlieria, Dionísio, and Timóteo (see articles in Tundisi & Saijo, 1997).
Types and Severity of Threats
Critical areas with endemic species such as Sergipe’s semi-deciduous forests and Bahia’s deciduous forests remain unprotected and are priority areas for conservation actions.
Justification of Ecoregion Delineation
The Bahia Interior forests were mapped according to the IBGE (1993) map, following the classification of semideciduous forest. The southern deliniation with the Paraña/Paraiba interior forests was made along the Rio Grande, Rio Preto, and Rio Paraiba due to distinct floral and faunal distributions (Stattersfield et al. 1998).
Fundação Instituto Brasilero de Geografia Estatística-IBGE. 1993. Mapa de vegetação do Brasil. Map 1:5,000,000. Rio de Janeiro, Brazil.
Nimer, E. 1979. Climatologia do Brasil. Rio de Janeiro: IBGE/SUPREN.
Sick, H. 1993. Birds in Brazil: A natural history. Princeton: Princeton University Press.
Stattersfield, A.J., M.J. Crosby, A.J. Long, and D.C. Wege. 1998. Endemic bird areas of the world: Priorities for conservation. BirdLife International, Cambridge, UK.
Tundisi, J. G., and Y. Saijo. 1997. Limnological studies on the Rio Doce Valley lakes, Brazil. São Paulo: Brazilian Academy of Sciences and University of São Paulo.
Veloso, H. P., A. L. R. R. Filho, and J. C. A. Lima 1991. Classificação da vegetação brasileira, adaptada a um sistema universal. Rio de Janeiro: IBGE/DERNA.
Prepared by: Jose Maria C. da Silva
Reviewed by: In process