43 research outputs found

    Mapping density, diversity and species-richness of the Amazon tree flora

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    Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution

    Unraveling Amazon tree community assembly using Maximum Information Entropy: a quantitative analysis of tropical forest ecology

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    In a time of rapid global change, the question of what determines patterns in species abundance distribution remains a priority for understanding the complex dynamics of ecosystems. The constrained maximization of information entropy provides a framework for the understanding of such complex systems dynamics by a quantitative analysis of important constraints via predictions using least biased probability distributions. We apply it to over two thousand hectares of Amazonian tree inventories across seven forest types and thirteen functional traits, representing major global axes of plant strategies. Results show that constraints formed by regional relative abundances of genera explain eight times more of local relative abundances than constraints based on directional selection for specific functional traits, although the latter does show clear signals of environmental dependency. These results provide a quantitative insight by inference from large-scale data using cross-disciplinary methods, furthering our understanding of ecological dynamics

    Unraveling Amazon tree community assembly using Maximum Information Entropy: a quantitative analysis of tropical forest ecology

    Get PDF
    In a time of rapid global change, the question of what determines patterns in species abundance distribution remains a priority for understanding the complex dynamics of ecosystems. The constrained maximization of information entropy provides a framework for the understanding of such complex systems dynamics by a quantitative analysis of important constraints via predictions using least biased probability distributions. We apply it to over two thousand hectares of Amazonian tree inventories across seven forest types and thirteen functional traits, representing major global axes of plant strategies. Results show that constraints formed by regional relative abundances of genera explain eight times more of local relative abundances than constraints based on directional selection for specific functional traits, although the latter does show clear signals of environmental dependency. These results provide a quantitative insight by inference from large-scale data using cross-disciplinary methods, furthering our understanding of ecological dynamics

    Mapping density, diversity and species-richness of the Amazon tree flora

    Get PDF
    Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution

    Effects of the essential oil from Eucalyptus globulus Labill on aflatoxin producer species

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    Há relatos na literatura de alguns compostos naturais de plantas que são usados para preservação de alimentos e no controle do desenvolvimento de fungos e bactérias que ocorrem em plantas, grãos, cereais e derivados. O presente trabalho teve como objetivo avaliar "in vitro" o efeito do óleo essencial de Eucalyptus globulus e seu composto majoritário sobre o crescimento micelial dos fungos Aspergillus flavus e Aspergillus parasiticus e a produção de aflatoxinas. A composição química do óleo analisado por cromatografia gasosa acoplada ao espectrofotômetro de massa mostrou-nos que o composto majoritário com 89,95% é o 1,8-cineol. Assim foi avaliada a ação por contato e por compostos voláteis do óleo essencial e do 1,8-cineol. O modo de ação por compostos voláteis, do óleo e do composto, foi estatisticamente mais eficiente do à ação por contato, para ambos os fungos. Independente do modo da ação a partir da dose de 500µL do óleo os fungos tiveram comportamentos semelhantes, com mais de 90% de inibição micelial. O composto 1,8-cineol não demonstrou a mesma eficiência que o óleo, produzindo algum efeito inibitório apenas na dose de 1.500µL, com apenas 5,5% de inibição de crescimento micelial. Foi verificado que o óleo essencial e o composto 1,8-cineol não cessaram a produção de aflatoxinas de ambos os fungos mesmo inibindo o crescimento micelial.Literature describes some natural plants composites that are used to preserve food and to control fungi and bacteria development in plants, grains, cereals and derivatives. The objective of this research was evaluate the effect in vitro of the Eucalyptus globulus essential oil and its major component over mycelial growth and aflatoxin production by Aspergillus flavus and Aspergillus parasiticus. The chemical oil composition, analyzed by gas chromatography connected to mass spectra, showed that 1,8-cineole is the major compound with 89.95%. Thus, the essential oil and the 1,8-cineole were evaluated by the contact and volatiles action. For both analyzed fungi, the oil and the compound action promoted throughout volatile compound were statically more efficient than the action promoted throughout contact. Considering the oil dose of 500µL and so forth, the fungi behaviors were similar independently of the action modes, with more than 90% of mycelial inhibition. The 1,8-cineole compound did not demonstrate the same efficiency that the essential oil did, producing some inhibitory effect only in the dose of 1.500µL, with only 5.5% of inhibition of mycelial growth. It was verified that the essential oil and 1,8-cineole compound did not cease the aflatoxins production in both fungi, even with the inhibition of mycelial growth

    Inibição do desenvolvimento fúngico através da utilização de óleos essenciais de condimentos Inhibition fungi growth through of utilization essential oils of spice

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    Objetivou-se com este trabalho avaliar os efeitos inibitórios, "in vitro", de óleos essenciais dos condimentos, alecrim (Rosmarinus officinalis L.), cebola (Allium cepa L.), manjericão (Ocimum basilicum L.), menta (Mentha piperita L.) e orégano (Origanum vulgare L.), sobre o desenvolvimento de fungos. Os óleos foram extraídos pela técnica de arraste a vapor e testados nas concentrações de 500; 1000; 1500 e 2000 mg/mL-1. Como culturas de teste foram utilizados os fungos Fusarium sp.; Aspergillus ochraceus Wilhelm.; Aspergillus flavus Link e Aspergillus niger van Tieghem obtidos da micoteca do EcoCentro/EPAMIG em Lavras, MG. O óleo essencial do orégano inibiu o desenvolvimento dos fungos testados em todas as concentrações exceto o fungo A. niger que teve o seu desenvolvimento micelial inibido a partir da concentração de 1000 mg/mL-1,. Os óleos de alecrim, menta, cebola e manjericão tiveram um efeito pronunciado a partir da concentração de 1500 mg/mL-1.The objective of this research was to evaluate "in vitro" effect of essential oils of the condiments, rosemary (Rosmarinus officinalis L. ), onion (Allium cepa L.), basil (Ocimum basilicum L.), mint (Mentha piperita L.) and oregano (Origanum vulgare L.) about fungi development. The essential oils were extracted by utilizing the vapor "dragging" technique and tested in the concentrations of 500; 1000; 1500 and 2000 mg/mL-1. The fungi Fusarium sp; Aspergillus ochraceus Wilhelm; Aspergillus flavus Link and Aspergillus niger van Tieghemwere obtained from the Fungal Culture Collection, EcoCentro/EPAMIG in Lavras, MG. The essential oil oregano inhibited completely the tested fungi development except the fungus A. niger that had its development inhibited starting from the concentrations of 1000 mg/mL-1. The rosemary, mint, onion and basil oils presented a pronounced effect starting from the concentration of 1500 mg/mL-1

    The Maximum Entropy Formalism of statistical mechanics in a biological application: a quantitative analysis of tropical forest ecology

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    In a time of rapid global change, the question of what determines patterns in species abundance distribution remains a priority for understanding the complex dynamics of ecosystems. The constrained maximization of information entropy provides a framework for the understanding of such complex systems dynamics by a quantitative analysis of important constraints via predictions using least biased probability distributions. We apply it to over two thousand hectares of Amazonian tree inventories across seven forest types and thirteen functional traits, representing major global axes of plant strategies. Results show that constraints formed by regional relative abundances of genera explain almost ten times more of local relative abundances then constraints based on either directional or stabilizing selection for specific functional traits, although the latter does show clear signals of environmental dependency. These results provide a quantitative insight by inference from large-scale data using cross-disciplinary methods, furthering our understanding of ecological dynamics

    Unraveling Amazon tree community assembly using Maximum Information Entropy : a quantitative analysis of tropical forest ecology

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    Funding: Floristic identification in plots in the RAINFOR forest monitoring network have been supported by the Natural Environment Research Council (grants NE/B503384/1, NE/ D01025X/1, NE/I02982X/1, NE/F005806/1, NE/D005590/1 and NE/I028122/1) and the Gordon and Betty Moore Foundation.In a time of rapid global change, the question of what determines patterns in species abundance distribution remains a priority for understanding the complex dynamics of ecosystems. The constrained maximization of information entropy provides a framework for the understanding of such complex systems dynamics by a quantitative analysis of important constraints via predictions using least biased probability distributions. We apply it to over two thousand hectares of Amazonian tree inventories across seven forest types and thirteen functional traits, representing major global axes of plant strategies. Results show that constraints formed by regional relative abundances of genera explain eight times more of local relative abundances than constraints based on directional selection for specific functional traits, although the latter does show clear signals of environmental dependency. These results provide a quantitative insight by inference from large-scale data using cross-disciplinary methods, furthering our understanding of ecological dynamics.Publisher PDFPeer reviewe

    Unraveling Amazon tree community assembly using Maximum Information Entropy: a quantitative analysis of tropical forest ecology.

    Get PDF
    In a time of rapid global change, the question of what determines patterns in species abundance distribution remains a priority for understanding the complex dynamics of ecosystems. The constrained maximization of information entropy provides a framework for the understanding of such complex systems dynamics by a quantitative analysis of important constraints via predictions using least biased probability distributions. We apply it to over two thousand hectares of Amazonian tree inventories across seven forest types and thirteen functional traits, representing major global axes of plant strategies. Results show that constraints formed by regional relative abundances of genera explain eight times more of local relative abundances than constraints based on directional selection for specific functional traits, although the latter does show clear signals of environmental dependency. These results provide a quantitative insight by inference from large-scale data using cross-disciplinary methods, furthering our understanding of ecological dynamics
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