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The traditional shade cacao plantations (cabrucas) of southern Bahia, Brazil, are biologically rich habitats, encompassing many forest-dwelling species. However, a critical question for the conservation management of this specific region, and the highly fragmented Atlantic forest in general, is to what extent the conservation value of cabrucas relies on the presence of primary forest habitat in the landscape. We investigated the relative importance of cabrucas and forests for the conservation of five diverse biological groups (ferns, frogs, lizards, birds and bats) in two contrasting landscapes in southern Bahia, one dominated by forest with some interspersed cabrucas, and one dominated by cabrucas with interspersed forest fragments. The community structure (richness, abundance and diversity) of all biological groups differed between cabrucas and forests, although these differences varied among groups. A high number of forest species was found in the cabrucas. However, there were pronounced differences between the two landscapes with regard to the ability of cabrucas to maintain species richness. Irrespective of the biological group considered, cabrucas located in the landscape with few and small forest fragments supported impoverished assemblages compared to cabrucas located in the landscape with high forest cover. This suggests that a greater extent of native forest in the landscape positively influences the species richness of cabrucas. In the landscape with few small forest fragments interspersed into extensive areas of shade cacao plantations, the beta diversity of birds was higher than in the more forested landscape, suggesting that forest specialist species that rarely ventured into cabrucas were randomly lost from the fragments. These results stress both the importance and the vulnerability of the small forest patches remaining in landscapes dominated by shade plantations. They also point to the need to preserve sufficient areas of primary habitat even in landscapes where land use practices are generally favorable to the conservation of biodiversity.

The impacts of forest fragmentation on the pteridophyte communities of the Una region of Bahia, Brazil, were investigated by comparing species richness and ensemble diversity among areas of large forest fragments (>900 ha), small forest fragments (<100 ha), and landscape matrix. We inventoried the pteridophytes below 1 m in height in interiors of small fragments, interiors of large fragments (control areas), edges of fragments, edges of continuous forest, capoeiras (initial stages of forest regeneration) and cabrucas (cocoa plantations). All ferns were collected following the plot method (plots of 120 · 10 m, each). Sampling units were established in the six main ecotypes of the Una region. These units were allocated within three sampling blocks of 5 per 5 km, which were chosen in order to include the largest forest patches that still remain. Results suggest that fragmentation has a negative impact on species richness at the matrix and the edges of forest remnants. A similar negative matrix end edge effect is reported for diversity of those sites measured by the a Log-series Index. However, small forest fragments have pteridophyte species richness and diversity rates similar to large ones so they should be considered of utmost importance to the conservation of forest-related species in the region.

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-(Edge effects on pteridophyte community in Atlantic rain forest of the Una region, South of Bahia State, Brazil). Edge effects are one of the most important consequences of forest fragmentation. This paper concerns how richness and abundance of pteridophytes vary when forest interiors and edges are compared on the fragmented Una landscape, state of Bahia. All ferns found up to 1 m above the ground were collected on 36 parcels of 120 × 10 m. Six sampling units were established on continuous forest areas (> 900 ha) and six more on forest fragments (≤ 100 ha). These units were allocated within three sampling blocks of 5 × 5 km over Una landscape. Each area had its parcels positioned at 20 m, 40 m, and further than 100 m from the border line, which was drawn by the cattle pastures areas passing through forest patches on the landscape. There was no significant variation of abundance among studied units, although richness decreases in all blocks, when parcels are closer to the matrix. Species richness is reestablished 20-30 m far from the border, where it has no significant difference to that of forest interior. In addition interior and border of forests are totally different environments, regarding pteridophytes community. Forest interior communities are almost not affected by edge effects. Therefore, border effects have a short penetration on pteridophytes communities, although a large scale raise on the amount of borders might result on the extinction of some local forest species.Key words -Bahia, edge effect, ferns, forest fragmentation RESUMO -(Efeitos de borda sobre a comunidade de pteridófitas na Mata Atlântica da região de Una, sul da Bahia, Brasil). Uma das conseqüências da fragmentação de hábitats florestais melhor estudadas até o momento são os chamados efeitos de borda. Neste estudo, foi verificado como variam a riqueza e a abundância das pteridófitas quando são comparados interiores e bordas de áreas florestais, em Una, BA. Foram inventariadas todas as pteridófitas a até 1 m do solo, em 36 parcelas de 120 × 10 m (0,12 ha), estabelecidas em áreas de mata contínua (> 900 ha) e fragmentos de mata (≤ 100 ha), distribuídas na região entre três blocos amostrais de 5 × 5 km. Em cada uma das áreas, locaram-se as parcelas a 20, 40 e a mais de 100 m da divisa da mata com relação às áreas adjacentes. Os resultados mostram que não há variação na abundância entre as unidades consideradas. No entanto, a riqueza de samambaias é diferente entre blocos amostrais, indicando que as florestas de Una podem ser heterogêneas quanto aos aspectos ambientais. Além disso, a riqueza decai nas parcelas de borda mais próximas à matriz, em todos os blocos; a partir de uma distância aproximada de 20-30 m a riqueza é restabelecida, tornando-se similar à do interior da floresta. Também fica claro que os interiores de floresta constituem ambientes totalmente distintos daqueles de borda, no que se refere à comunidade de pteridófitas, de modo que, praticamente, não são afetados pelos efeitos de borda. Pôde-se concluir que os efeito...

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Twelve extracts obtained from nine plants belonging to six different genera of Clusiaceae were analyzed against Gram-negative (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus and Enterococcus faecalis) bacteria using the microdilution broth assay. Tovomita aff. longifolia, T. brasiliensis, Clusia columnaris, Garcinia madruno, Haploclathra paniculata, and Caraipa grandifolia extracts showed significant results against the bacteria. The organic extract obtained from the leaves of T. aff. longifolia showed minimal inhibitory concentration (MIC) = 70 µg/ml and minimal bactericidal concentration (MBC) = 90 µg/ml against E. faecalis and the organic extract made with the stem of C. columnaris showed MIC = 180 µg/ml and MBC = 270 µg/ml against P. aeruginosa. None of the antibacterial extracts showed lethal activity against brine shrimp nauplii. On the other hand, both aqueous and organic extracts obtained from the aerial organs of Vismia guianensis that were cytotoxic to brine shrimp nauplii did not show a significant antibacterial activity in the assay.Key words: antibacterial -cytotoxicity -Clusiaceae -Amazon rain forest -Brazil Natural products are considered an important source of new antibacterial agents. Drugs derived from unmodified natural products or drugs semi-synthetically obtained from natural sources corresponded to 78% of the new drugs approved by the FDA between 1983 and 1994(Cragg et al. 1997). This evidence contributes to support and quantify the importance of screening natural products. Previous screening works were done with more than 700 Amazon rain forest plant extracts, and results can be seen elsewhere (Frana & Suffredini 2002, Suffredini et al. 2002a, b 2004, Nepomuceno et al. 2003.Less than 20% of the Angiospermae have been screened for biological activity, and taking the Brazilian rain forests in concern, not much has been done so far. Brazil is home to more than 20% of the world's biodiversity, and the Amazon rain forest concentrates 17% of the biodiversity found within the country (Wilson & Peter 1988). For this reason, our research team has been systematically studying the antibacterial activity of organic and aqueous plant extracts obtained from plants native to the rain forest against Gram-positive Staphylococcus aureus ATCC 29213 (Sau) and Enterococcus faecalis ATCC 29212 (Efae) and Gram-negative Pseudomonas aeruginosa ATCC 27853 (Psa) and Escherichia coli ATCC 25922 (Ecol) with the aim of discovering new natural product compounds that can be used as antibiotics. Twelve aqueous and organic extracts obtained from plants belonging to six different genera of Clusiaceae (Vismia, Garcinia, Haploclathra, Tovomita, Caraipa, and Clusia) were submitted to the determination of the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) using the microdilution broth assay (Suffredini et al. 2004). The extracts were also tested against brine shrimp nauplii in order to evaluate their potential as cytotoxic agents and to determine if ...