Location and General Description
Bahia coastal forest covers a 150-km wide strip along the Atlantic Coast of Bahia and Espirito Santo states in Brazil. The climate is hot and humid with 1,200 to 1,800 mm of rainfall evenly distributed throughout the year (Mori & Boon 1983). A dry period, from May through September, sometimes occurs in the ecoregion’s southern portion (Peixoto and Gentry 1990). Forests cover Tertiary sedimentary plateaus (Formation Barreiras), limited westward by the ancient slopes of Serra da Mantiqueira Mountain Range (IBGE 1985). The Itapicuru River limits the ecoregion northward. Tropical nutrient-impoverished soils are prevalent (yellow-red latosol and podzols) (IBGE 1985).
Forests are spread over the low elevation plateaus and marine deposits at 30 m elevation. The main types of vegetation are the Atlantic moist and semi-deciduous forests, four strata vegetations with emergent trees taller than 35 m (Veloso et al. 1991). The emergent and canopy layers are rich in tree species of Leguminosae (Dalbergia nigra, Caesalphinia echinata), Sapotaceae (Manilkara longifolia), Lecythidaceae (Lecythis lurida) and Chrysobalanaceae (Licania micrantha) (Mori & Boon 1983, Peixoto & Gentry 1990). Bahia coastal forests are similar in both structure and composition to Amazonian forests, but they harbor a unique set of endemic species (Prance 1987, Mori & Boon 1983). Such characteristics set this ecoregion apart from other portions of the Brazilian Atlantic forest.
Bahia Bahia coastal forests have been given highest priority for biodiversity conservation because they harbor an extraordinary number of endemic species of vascular plants (Prance 1987), birds (Haffer 1987), primates (Mendes 1999), and butterflies (Brown Jr.1987). Endemic species include three genera of legumes (Brodriguesia, Arapatiella, and Harleyodendron), four genera of bambusoid grasses (Atractantha, Anomochloa, Alvimia, and Sucrea), seven species of Inga, and the important piaçava palm, Atalea funifera (Thomas et al. 1998). Recent plant surveys in two protected areas (Una and Serra Grande Biological Reserves) found that 41 to 44 percent of vascular plant species are endemic to Atlantic forest and that 26 to 28 percent are endemic to the ecoregion (Thomas et al. 1998). Alpha diversity is also very high (Peixoto & Gentry 1992). For example, Una Biological Reserve (70 km2) and Serra Grande Biological Reserve (3 km2) harbor 420 and 430 vascular plant species, respectively (Thomas et al. 1998). In addition to having so many endemics, Bahia coastal forests appear to contain many primitive plant species. As a result, they are considered to be the dispersal centers for some primitive groups of bamboos (Soderstrom& Calderón 1974). Mammal species threatened with extinction Maned Three-toed Sloth (Bradypus torquatus) and Golden-headed Lion Tamarin (Leontopithecus chrysomelas) and trees facing the same threat (Dalbergia nigra) are found in forest remnants of this ecoregion (Fonseca et al. 1994). For several Amazonian species of plants and birds, Bahia coastal forests also represent the northernmost limit of their ranges in the Atlantic forest (Bigarella et al. 1975, Prance 1979).
The forests of coastal Bahia are considered among the more endangered habitats on Earth (Mori & Boon 1983) because they have been reduced by 95 percent (Viana et al. 1997). In southern Bahia, only 0.4 percent of the original forest remains (Thomas et al. 1998). At present, forest conversion into pasture is occurring at alarming rates stimulated by the economic crash of cocoa plantations (Araujo et al. 1998). Remaining natural vegetation is represented by approxmiately 9,532 km2 of moist, semi-deciduous and associated restinga forests (SOS MATA ATLÂNTICA. 1993). The largest blocks of habitat are protected by Sooretama Biological Reserve (240 km2), and by Linhares Forest Reserve (220 km2). Natural protected areas cover 920.03 km2 (0.9 percent of the ecoregion) of both lowland moist and semi-deciduous forests.
Types and Severity of Threats
New economic activities based on raising cattle represent a large threat to the ecosystem. There are 5,000 km2 of Atlantic forest associated with cocoa plantation that might be converted to pasture (Araujo et al. 1998). Such activities would increase the habitat loss and forest fragmentation with all deleterious impacts associated with those processes.
Justification of Ecoregion Delineation
The Bahia Coastal forests were mapped following the "Atlantic forest: dense ombrophilous forest" classification of IBGE (1993). Deliniations was derived by combining various vegetative types within this broader classification, including: secondary vegetation, submontane, montane, and lowland (terras baixas). This is an important areas of endemism (Stattersfield et al 1998), exhibits greater coastal influence, and host distinct flora and fauna from the neighboring Bahía Interior forests.
ARAUJO, M., ALGER, K., ROCHA, R. & MESQUITA, C. A. B. 1998. Mata Atlântica do Sul da Bahia. Cadernos da Reserva da Biosfera da Mata Atlântica 8:5-35.
BigarellaI, J.J., D. Andrade-Lima, and P.J. Riehs. 1975. Considerações a respeito das mudanças paleoambientais na distribuição de algumas espécies vegetais e animais do Brasil. Anais Academia Brasileira de Ciâncias 47(supl.):411-464.
Brown, Jr. K.S. 1987. Biogeography and evolution of neotropical butterflies. Pages 66-104 in T.C. Whitmore, and G.T. Prance, editors, Biogeography and quaternary history in tropical America. Claredon Press, Oxford.
Fonseca, G.A.B., A.B. Rylands, C.M.R. Costa, R.B. Machodo, and Y.R.L. Leite, editors, 1994. Livro vermelho dos mamíferos brasileiros ameaçados de extinção. Fundação Biodiversitas, Belo Horizonte.
Fundação Instituto Brasilero de Geografia Estatística-IBGE. 1993. Mapa de vegetação do Brasil. Map 1:5,000,000. Rio de Janeiro, Brazil.
Haffer, J. 1987. Biogeography of neotropical birds. Pages 105-150 in T.C. Whitmore, and G.T. Prance, editors, Biogeography and quaternary history in tropical America. Claredon Press, Oxford. pp. 105-150.
IBGE. 1985. Atlas Nacional do Brasil: Região Nordeste. IBGE, Rio de Janeiro.
Mendes, S.L. 1999. Grupo mamíferos- documento preliminar. In: Conservation International, editor, Workshop Avaliação e Ações Prioritárias para Conservação dos Biomas Floresta Atlântica e Campos Sulinos, São Paulo. http//www.conservation.org.
Mori, S.A., and Boom, B.M. 1983. Southern Bahian moist forest. The Botanical Review 49:146-232.
Peixoto, A. L., and A.H. Gentry. 1990. Diversidade e composição florística da mata de tabuleiro na Reserva Florestal de Linhares (Espiríto Santo, Brasil). Revista Brasileira de Botânica 13:19-25.
Prance, G.T. 1979. The taxonomy and phytogeography of the Chrysobalanaceae of the Atlantic coastal forests of Brazil. Revista Brasileira de Botânica 2:19-39.
Prance, G.T. 1987. Biogeography of neotropical plants. Pages 175-196 in T.C. Whitmore, and G.T. Prance, editors, Biogeography and quaternary history in tropical America. Claredon Press, Oxford.
Soderstrom, T.R. and C.N. Calderó. 1974. Primitive forest grasses and the evolution of the Bambusoideae. Biotropica 6:141-153.
SOS MATA ATLÂNTICA. 1993. Mapa de remanescentes da floresta Atlântica nordestina. In: Sociedade Nordestina de Ecologia , Conservation International e Fundação Biodiversitas (ed.). Workhop Prioridades para a Conservação da Floresta Atlântica do Nordeste, Recife. http// www.bdt.org
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.
Thomas, W.W., Caralho, A.M.V., Amorin, A. M. A., Garrison, J., and A.L. ArbelÁez. 1998. Plant endemism in two forests in southern Bahia, Brazil. Biodiversity and Conservation 7:311-322.
Veloso, H. P., A.R.L. Rangel-Filho, and J.C.A. Lima. 1991. Classificação da vegetação brasileira adaptada a um sistema universal. IBGE, Rio de Janeiro.
Viana, V. M., A.J. Tabanez, and J.L. Batista. 1997. Dynamics and restoration of forest fragments in the Brazilian Atlantic moist forest. Pages 351-365 in W.F. Laurance, and R.O. Bierregaard Jr, editors, Tropical forest remnants: ecology, management, and conservation of fragmented communities. University of Chicago Press, Chicago.
Prepared by: Jose Maria C. da Silva
Reviewed by: In process