RESUMOO presente estudo teve como objetivo descrever atributos funcionais de espécies arbóreas em um fragmento de Floresta Ombrófila Mista em Lages -SC, com o propósito de agrupá-las funcionalmente. Para cada uma das 20 espécies mais abundantes na área de estudo foi amostrado um total de 10 indivíduos e determinada a média da densidade da madeira e o tamanho médio das folhas. Dessas espécies, também foi descrito o regime de renovação foliar, a síndrome de dispersão de propágulos e a altura máxima no fragmento. Os resultados de altura máxima e de densidade da madeira sugerem a existência de um trade-off entre o investimento de recursos para o crescimento em altura, garantindo o acesso à maior disponibilidade lumínica, ou em densidade da madeira, permitindo maior capacidade de resistência e sobrevivência em um ambiente sombreado de sub-bosque. As gimnospermas Araucaria angustifolia e Podocarpus lambertii apresentaram as folhas de menor tamanho, enquanto Cupania vernalis, Jacaranda puberula e Matayba elaeagnoides, todas de folhas compostas, apresentam as maiores folhas. Quatro grupos funcionais se destacaram: 1) perenes de folhas grandes, 2) perenes de folhas pequenas, 3) decíduas zoocóricas e 4) decíduas não zoocóricas. Os resultados demonstraram que as espécies mais abundantes do fragmento de Floresta Ombrófila Mista estudado apresentam variações dos atributos funcionais avaliados, sugerindo
-This paper aims at characterizing the tree species natural regeneration and evaluating the relation of this stratum to both the adult component and the environmental variables in a fragment of a cloud forest in Santa Catarina, Brazil. In each of 25 20 × 20 m plots, where the adult component and environmental variables have previously been evaluated, subplots of different sizes varying according to plants' height were then allocated as follows: Class 1 -plants with a height varying from 0.15 cm up to 1 m, being evaluated within 5 m 2 ; Class 2 -plants with a height varying from 1 up to 3 m, being evaluated within 10 m 2 ; Class 3 -plants with a height greater than 3 m and DBH smaller than 5 cm, being evaluated within 20 m 2 . Data have been analyzed with regard to the determination of diversity (Shannon index), evenness (Pielou), Natural Regeneration Index (NRI), similarity with the adult component (Jaccard and Bray-Curtis), floristic-structural organization (Nonmetric Multidimensional Scaling -NMDS) and their relation to environmental variables. A total of 518 individuals distributed in 28 species were sampled. The low values of Shannon index (2.51 nat/ind) and evenness (0.75) suggest low diversity and elevated ecological dominance. The highest NRI has been found in the species Symphyopappus itatiayensis (Hieron.) R.M. King & H.Rob (19.36%). The similarity with the adult component were of 0.45 (Jaccard) and 0.24 (BrayCurtis), demonstrating a low overall similarity (<0.50). The soil compaction was the only variable that has shown a relation with regeneration, which can be related to cattle's presence in the fragment.Keywords: Phytosociology; Araucaria Forest; Forest management. REGENERAÇÃO NATURAL DE ESPÉCIES ARBÓREAS EM UMA FLORESTA NEBULAR EM SANTA CATARINA, BRASILRESUMO -Os objetivos do presente estudo foram caracterizar a regeneração natural arbórea e relacionar esse estrato com o componente adulto e com variáveis ambientais em um fragmento de floresta nebular em Santa Catarina. Em cada uma das 25 parcelas de 20 × 20 m, onde previamente foi realizado um estudo com caracterização do componente adulto e de variáveis ambientais, foram estabelecidas subparcelas, com tamanhos diferenciados de acordo com o tamanho das plantas, para a avaliação dos regenerantes: Classe 1, plantas com altura de 0,15 cm até 1 m, avaliadas em 5 m²; Classe 2, plantas com altura entre 1 e 3 m, avaliadas em 10 m², e; Classe 3, plantas com altura maior que 3 m e DAP menor que 5 cm, avaliadas em 20 m². Foram determinadas: diversidade (índice de Shannon), equabilidade (Pielou), Índice de Regeneração Natural (IRN), 1074Revista Árvore, Viçosa-MG, v.40, n.6, p.1073-1082, 2016 DALLA ROSA, A. et al.
The aim of the present study was to characterize the floristic-structural heterogeneity of the tree species in an alluvial forest remnant considering three sectors: forest-river edge, forest interior and forest/non-forest matrix edge. Forty-eight plots of 200 m 2 were allocated and all tree individuals with a diameter at breast height (dbh) equal to or greater than 5 cm were measured and identified. Data was analyzed by Shannon's diversity index, Pielou evenness and phytosociological descriptors. Plots were ordered through NMDS. Sixty-six species were sampled and Myrtaceae was found to be the richest family. Diversity and evenness reached 2.96 and 0.71, respectively. Sebastiania commersoniana (Baill.) L.B.Sm. & Downs presented the highest importance value (21.22%). The NMDS showed that tree components are spatially partitioned according to sectors, therefore indicating floristic-structural heterogeneity.
ResumoO objetivo do presente trabalho foi verificar a influência do efeito borda sobre a diversidade e a participação de diferentes guildas de regeneração em um fragmento florestal nativo em contato com reflorestamento de pínus. Para isso, foram amostrados o estrato arbóreo adulto (DAP -diâmetro à altura do peito ≥ 5 cm) e regenerante (altura maior que 15 cm e DAP < 5 cm) em cinco transeções de 20 x 100 m perpendiculares à borda do fragmento. Cada transeção foi subdividida em cinco subparcelas de 20 x 20 m, definindo-se os setores representando o gradiente borda-interior: 0-20 m, 20-40 m, 40-60 m, 60-80 m e 80-100 m. As espécies foram classificadas em guildas de regeneração: pioneira, clímax exigente em luz e clímax tolerante a sombra. Foram determinadas a diversidade (Índice de Shannon) e a abundância das guildas em cada setor e estrato. Os dados foram analisados pelo teste t de Hutcheson e teste de proporção. Enquanto que no estrato adulto não houve variações na diversidade ao longo do gradiente borda-interior, no componente regenerativo a maior diversidade foi observada na borda (0-20 m). Apenas no estrato adulto foram observadas variações na participação relativa das guildas, com maior concentração de indivíduos de pioneiras nos primeiros 40 m. Palavras-chave: Ecologia; fragmentação de hábitats; Floresta Ombrófila Mista. Abstract Diversity and regeneration guilds of tree species in an edge of a natural forest in contact with a pinus plantation.The objective of the present study was to verify the influence of edge-effect on diversity and regeneration guilds participation in a forest fragment in contact with a Pinus plantation. For this, the adult (dbh -diameter at breast height≥5 cm) and regenerative (height higher than 15 and dbh<5 cm) components were sampled in five, 20×100 m, transects perpendiculars to the edge of a fragment. Each transect was subdivided in five, 20×20 m, subplots, defining the following sectors representing the edge-interior gradient: 0-20 m, 20-40 m, 40-60 m, 60-80 m and 80-100 m. The species were classified according to the following regeneration guilds: pioneer, light demanding climax and shade tolerant climax. The diversity (Shannon Index) and guilds abundance in each sector were determined. The data were analyzed by Hutcheson t test and proportion test. While no variation was observed for the adult component, the highest of diversity was observed in the edge (0-20 m) for the regenerative component. Variations along the edge gradient of the relative participation of guilds were observed only for adults, with a concentration of Pioneer within the first 40 m.
There are many species of the Eucalyptus genus presents high levels of the growth stress. These stresses are mechanical efforts generated during the tree growth to help maintaining the balance of the cup in response to environmental and silvicultural agents. The stresses are responsible for the cracks of tops and for the warp after unfolding. The objective of this study was to test five different methods to minimize the effects of growth stress on the production of Eucalyptus urophylla sawlogs. The boards produced were then evaluated and measured for cracking, arching, curvature and cupping. The treatment with herbicide presented the smallest medium indexes of cracking (16.63 cm) and of arching (0.23 mm.m-1), while the medium curvature was smaller than observed in boards unfolded in 72 hours after the reduction of the trees (0.88 mm.m-1). Unfolding after ten days of harvesting represented the less efficient technique in the cracking control, curvature and arching. The cupping was not observed during boards processing. The herbicide application was more efficient in the reduction of the effects of the growth tensions.
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