Habitat fragmentation is one of the leading causes of edge genesis and its effects. Functional tree traits such as wood density, height, and diameter are essential variables from which it is possible to infer several ecological processes. This study assessed the variability of the functional traits of trees over two habitats (edge and interior) of a forest remnant. The hypothesis tested were i) the functional traits would have lower values at the edges than the interior, and ii) environmental variables would influence such differences. This study was carried out in the largest Atlantic Forest remnant within Serra da Tiririca State Park, Brazil, by establishing ten plots (50 × 20 m) among different habitats. Within each plot, wood samples were taken from all trees with a diameter of = 10 cm. It was recorded the altitude, distance from the plots to the edge, and fire records as possible explanatory variables (environmental variables). Wood density was obtained using the immersion method. To verify differences in functional traits by habitat, the Wilcoxon test was applied. Additionally, the influence of explanatory variables on functional traits through generalized linear models was evaluated. One hundred eighty-five trees were recorded at the edges and 218 trees at the interior of the remnant. Wood density and tree height were significantly lower in the edges than in the interior. Furthermore, the best models indicated significant relationships between wood density and habitats, as well as diameter and distance to the edge. This study was effective in raising suitable variables to predict edge effects.

The Atlantic Forest is one of the richest and most threatened biomes in Brazil. However, the structure and floristic composition of many of its remnants are still unknown. This study assessed the structure and tree composition of the Serra da Tiririca – SET coastal remnant, is the largest remnant in Serra da Tiririca State Park – PESET (Atlantic Forest, RJ). In ten 50 × 20 m plots installed between the edges and the interior of the remnant, we registered 403 trees distributed in 29 families, 59 genera, and 126 species. The richest and most abundant families were Fabaceae, Myrtaceae, and Meliaceae, while the most representative species were Gallesia integrifolia towards the interior of the remnant and Piptadenia gonoacantha towards the edges. The remnant had an average Shannon-Wiener Diversity of 3.69, a total basal area of ​​19.3 m2/ha, and an average diameter and height of 20.42 cm and 11.8 m, respectively. This study shows that the SET remnant is floristically heterogeneous and has distinct structural characteristics and stretches in different successional stages related to edge and interior gradients. Anthropogenic pressures on the remnant are likely to persist and are evidenced mainly by the forest structure.

Objetivou-se avaliar o efeito de borda com base nas diferenças dos atributos funcionais das árvores (densidade da madeira, diâmetro e altura) na restinga de Grumari, RJ, região de Floresta Atlântica. Em campo, delimitaram-se duas bordas: Banco Halles e Lagoa Feia. Em cada borda foram selecionadas árvores com diâmetro ≥ 10 cm. Registrou-se o diâmetro e a altura de cada árvore, sendo também coletadas amostras de madeira. A densidade da madeira foi obtida pelo método de imersão. Os testes t de Student e Wilcoxon foram utilizados na análise dos atributos funcionais para verificação de diferenças entre bordas. A correlação de Pearson foi aplicada para constatar relações entre os atributos. Adicionalmente, estimou-se a biomassa das árvores e comparou-se a média entre bordas. Foi observado que apenas a altura apresentou diferenças significativas entre bordas (t 2,55; p 0,02). Os atributos funcionais não apresentaram relações significativas entre si e a borda Banco Halles apresentou maior estoque médio de biomassa (126,48 ± 71,14 kg) do que Lagoa Feia (71,5 ± 40,67 kg). Este estudo sugere que o efeito de borda poderia estar influenciando a variação dos atributos funcionais em um mesmo remanescente com diferentes históricos de distúrbio e ocupação.

Vachellia macracantha (ex Acacia macracantha) is one of the most important tree species in the Seasonally Dry Tropical Forest (SDTR) of northern Peru. The study aims to develop an efficient callus induction and micropropagation protocol from microcuttings of adult trees of this mentioned species, distributed across the North of Peru to the South of Ecuador. Shoot and uninodal microcuttings from three to five-year-old plants were investigated respecting their vegetative propagation and rooting capacity in vitro. High levels of NAA (2.5 to 7.5 mg L-1) were most efficient for shoot elongation and axillary bud development, although the basal callus formation and defolitation occurrence was also very high. In this case, the NAA 0.02 mg L-1, BAP 0.05, and GA3 0.05 mg L-1 interaction has been produced a better multiplication rate after 30 days without both basal callus formation and defoliation. Our findings suggest that other treatments tested such as NAA-BAP, NAA-KIN and NAA-2iP interaction, not were significantly satisfactory. Rooting response and consequently shoot elongation were always better with IBA (0.5 to 2.0 mg L-1) than NAA, under the same growth regulators concentrations.

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