FITOSSOCIOLOGIA DE FRAGMENTOS DE FLORESTA ESTACIONAL DECIDUAL NO ESTADO DE SANTA CATARINA – BRASIL

http://dx.doi.org/10.5902/1980509816582This study aimed to evaluate the species composition and structure of  Seasonal Deciduous Forest in the southern Brazilian state of Santa Catarina, including the tree/shrub component and the natural regeneration. We also compared the floristic composition between the components and discussed about the conservation condition of forests. The study was based on sample plots established by the Floristic and Forest Inventory of Santa Catarina state. Tree/shrub component was sampled by 78 plots placed systematically with 4,000 m² of sample area each, were individuals with DBH (diameter at breast height) ≥ 10 cm was measured. Regeneration (DBH 1.50 m) was sampled in subplots of 100 m² each. Structure and diversity of sample plots were analyzed in both components; species were classified by their ecologic group. To test the association between components was made a Non-metric Multidimensional Scaling (NMSD) and Mantel test. We sampled 245 species, among them 215 in the tree/shrub component (79 of them exclusive), 165 species in the natural regeneration (30 exclusive ones) and 136 species common to the two components. The association between components was confirmed with NMSD and Mantel test (r = 0.34; p = 0.001). Species with major importance value were mostly early secondary species that emphasizes the consequences of long term exploitation and degradation of Seasonal Deciduous Forest in Santa Catarina.http://dx.doi.org/10.5902/1980509816582O estudo objetivou avaliar a fitossociologia da Floresta Estacional Decidual no Estado de Santa Catarina, em seus componentes arbóreo/arbustivo e regeneração natural, bem como comparar estes quanto à composição florística e inferir sobre o estádio de conservação dos remanescentes. Foram usados dados de 78 unidades amostrais levantadas no Inventário Florístico Florestal do Estado de Santa Catarina. Em cada unidade amostral foram amostrados os componentes arbóreo/arbustivo (DAP ≥ 10 cm) em 4000 m2 e a regeneração natural (altura ≥ 1,50 m; DAP < 10 cm) em 100 m2. Foi efetuado o cálculo dos parâmetros fitossociológicos e índices de diversidade de Shannon e equabilidade, bem como, classificaram-se as espécies quanto ao grupo ecológico. Para verificar a associação entre os dois componentes executou-se uma análise de ordenação NMSD (Non-metric Multidimensional Scaling) seguida do Teste de Mantel. Foram amostradas 245 espécies, sendo 215 no componente arbóreo/arbustivo e 79 exclusivas deste, 165 na regeneração natural e 30 exclusivas deste e, 136 comuns aos dois componentes. A NMDS apresentou uma tendência de associação entre as matrizes dos dois componentes, o que foi confirmado pelo Teste de Mantel (r = 0,34; p = 0,001). A composição florística, bem como as espécies com maiores valores de importância se constituíram predominantemente de espécies secundárias, fato que evidencia o histórico de exploração e degradação da Floresta Estacional Decidual no Estado

Efeitos de filtros ambientais nos padrões de diversidade de árvores na floresta atlântica do sul do Brasil sob uma perspectiva de metacomunidades

Entender padrões de diversidade e composição de espécies ao longo de múltiplas escalas espaciais constitui um dos principais objetivos em ecologia e biogeografia. A relativa importância dos mecanismos responsáveis por estruturar as comunidades de plantas e como eles interagem para influenciar estes padrões têm sido foco de intensos debates. No presente estudo, foram utilizados dados do Inventário Florístico Florestal de Santa Catarina a fim de investigar os padrões de diversidade de espécies de árvores e suas relações com a heterogeneidade ambiental sob uma das perspectivas oriundas da teoria de metacomunidades, conhecida como “sorteio de espécies”. A predição chave deste ponto de vista é a de que a composição de espécies varia em resposta a diferenças nas condições ambientais entre manchas de hábitat. O presente estudo é focado nessa predição e objetivou entender como processos relacionados a filtros ambientais interagem direta e indiretamente sobre os padrões de diversidade em uma área de 95000 km 2 (dados de 432 unidades amostrais). Foi utilizada modelagem de equações estruturais (PLS Path Modeling), a fim de investigar os efeitos interativos da topografia, clima, balanço de água e energia e geometria das manchas de floresta sobre os padrões de alfa (α) e beta (β) diversidade de uma metacomunidade de floresta atlântica no sul do Brasil. Fatores relacionados a filtros ambientais mostraram substanciais efeitos sobre a diversidade alfa e beta. A quantidade total da variação na beta diversidade explicada pela filtragem de hábitat foi alta (64%), corroborando a predição testada no nível de metacomunidades. Os fatores mais importantes para explicar a diversidade beta foram: extremos climáticos, balanço de água e energia e alfa diversidade, enquanto tamanho da mancha e balanço de água e energia foram os fatores chaves para a alfa diversidade. O teste de Mantel parcial mostrou que os efeitos ambientais ocorrem amplamente independente de efeitos espaciais, reforçando a predição testada. O estudo provê forte suporte empírico para a predição de que a beta diversidade reflete primariamente processos determinísticos associados com o nicho das espécies e suas respostas às condições ambientais na escala espacial considerada.Understanding patterns of species diversity and composition across multiple scales is one of the main purpose in ecology and biogeography. The relative importance of the mechanisms that structure plant communities and how they interact to influence these patterns remains a topic of hot debate. In the present study, we use data from the Forest Inventory of Santa Catarina to investigate the patterns of species diversity of subtropical Atlantic forests and its relationships with environmental heterogeneity on a metacommunity perspective (species-sorting). The key prediction of this viewpoint is that community composition varies in response to differences in environmental conditions among habitat patches. Our study focused on this perspective, aiming to understand how environmental filtering processes interact directly and indirectly on diversity patterns in an area of 95000 km 2 (data from 432 forest plots). We employed structural equation modeling (PLS Path Modeling) to disentangle the interactive effects of topography, climate, water-energy balance, and geometry of forest patches upon the alpha and beta diversity of a subtropical forest metacommunity in southern Brazil. Factors related to environmental filtering showed substantial effects upon tree alpha and beta diversity. The total amount of variation in beta diversity explained by environmental filtering was high (64%) and was even more when together with alpha diversity (73%), corroborating the prediction of species-sorting model at the metacommunity level. Climatic extremes, water-energy balance and alpha diversity were the key determinants of beta diversity and patch size and water- energy balance the key determinants of alpha diversity in the South Brazilian Atlantic forests. Partial mantel test showed that environmental effects occurred largely independent of spatial effects, reinforcing the tested prediction. Our study provides strong empirical support for the prediction that beta diversity primarily reflects deterministic factors associated with species niches and their responses to environmental conditions in the studied spatial scale

Functional patterns of tree communities in natural Araucaria forests and old monoculture conifer plantations

A functional perspective of tree communities is helpful for understanding forest dynamics, especially vegetation recovery after other land uses. Knowledge about ecological filters and survival strategies of trees are also important for the restoration of degraded areas. This study aimed to evaluate the functional composition and structure of adult and regenerative components of natural Araucaria forests, Araucaria plantations and plantations of exotic Pinus in subtropical southern Brazil. Differences in functional diversity and functional richness, and in community weighted mean trait values, including leaf traits and reproductive traits, were analyzed. RLQ analysis was used to assess the association between community structure, plant traits and environmental variables. Clear differences were found for most traits and for functional richness for the regenerative component, while the adult component was more similar among forest types. A clear separation in RLQ ordination associated with trait variation, for the adult component but not for regenerative trees, also indicates that communities are becoming functionally more similar with time. Plantations were shown to function as environmental filters by directly influencing species recruitment, richness and functional diversity. We conclude that passive restoration may be the best strategy for restoration of Araucaria forests

Floristic and Forest Inventory of Santa Catarina: species of evergreen rainforest

This study presents the list of species of Evergreen Rainforest in Santa Catarina, based on 202 sample units established by the Floristic and Forest Inventory of Santa Catarina, in order to study the tree/shrub component and regeneration in addition to a floristic survey outside the sample units. We recorded 1,473 species: three gymnosperms and 1,470 angiosperms, that totalize 19% of all species quoted for this Brazilian forest type. The most species-rich families were Orchidaceae (143 species), Myrtaceae (142), Asteraceae (98), Melastomataceae (86), Fabaceae (78), Rubiaceae (65), Solanaceae (61), Bromeliaceae (57), Piperaceae (56), and Lauraceae (52). Among them are eight species listed in the Official List of Endangered Species of the Brazilian Flora: Aechmea blumenavii, Araucaria angustifolia, Billbergia alfonsijoannis, Euterpe edulis, Heliconia farinosa, Ocotea catharinensis, O. odorifera and, O. porosa

PHYTOSOCIOLOGY OF SEASONAL DECIDUOUS FOREST FRAGMENTS IN SANTA CATARINA STATE \u2013 BRAZIL

O estudo objetivou avaliar a fitossociologia da Floresta Estacional Decidual no Estado de Santa Catarina, em seus componentes arboreo/arbustivo e regeneracao natural, bem como comparar estes quanto a composicao floristica e inferir sobre o estadio de conservacao dos remanescentes. Foram usados dados de 78 unidades amostrais levantadas no Inventario Floristico Florestal do Estado de Santa Catarina. Em cada unidade amostral foram amostrados os componentes arboreo/arbustivo (DAP 65 10 cm) em 4000 m2 e a regeneracao natural (altura . 1,50 m; DAP &lt; 10 cm) em 100 m2. Foi efetuado o calculo dos parametros fitossociologicos e indices de diversidade de Shannon e equabilidade, bem como, classificaram-se as especies quanto ao grupo ecologico. Para verificar a associacao entre os dois componentes executou-se uma analise de ordenacao NMSD (Non-metric Multidimensional Scaling) seguida do Teste de Mantel. Foram amostradas 245 especies, sendo 215 no componente arboreo/arbustivo e 79 exclusivas deste, 165 na regeneracao natural e 30 exclusivas deste e, 136 comuns aos dois componentes. A NMDS apresentou uma tendencia de associacao entre as matrizes dos dois componentes, o que foi confirmado pelo Teste de Mantel (r = 0,34; p = 0,001). A composicao floristica, bem como as especies com maiores valores de importancia se constituiram predominantemente de especies secundarias, fato que evidencia o historico de exploracao e degradacao da Floresta Estacional Decidual no Estado.This study aimed to evaluate the species composition and structure of Seasonal Deciduous Forest in the southern Brazilian state of Santa Catarina, including the tree/shrub component and the natural regeneration. We also compared the floristic composition between the components and discussed about the conservation condition of forests. The study was based on sample plots established by the Floristic and Forest Inventory of Santa Catarina state. Tree/shrub component was sampled by 78 plots placed systematically with 4,000 m2 of sample area each, were individuals with DBH (diameter at breast height) 65 10 cm was measured. Regeneration (DBH &lt;10 cm and height &gt;1.50 m) was sampled in subplots of 100 m2 each. Structure and diversity of sample plots were analyzed in both components; species were classified by their ecologic group. To test the association between components was made a Non-metric Multidimensional Scaling (NMSD) and Mantel test. We sampled 245 species, among them 215 in the tree/shrub component (79 of them exclusive), 165 species in the natural regeneration (30 exclusive ones) and 136 species common to the two components. The association between components was confirmed with NMSD and Mantel test (r = 0.34; p = 0.001). Species with major importance value were mostly early secondary species that emphasizes the consequences of long term exploitation and degradation of Seasonal Deciduous Forest in Santa Catarina