291 resultados para Leptodactylus araucaria


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A utilização de gradientes ambientais no estudo de comunidades vegetais possibilita a eleição de sítios onde há a predominância de um fator abiótico que determina o sucesso ou o fracasso de espécies ao longo de sua extensão. Entre as inúmeras ferramentas utilizadas no estudo de gradientes climáticos, se destaca a anatomia do lenho, pois, é um ramo da ciência que permite analisar, além dos aspectos espaciais, os aspectos temporais dos sítios por meio dos anéis de crescimento. Além disso, a ampla distribuição das plantas lenhosas ao longo do globo possibilita análises em praticamente todos os tipos de biomas e ecossistemas terrestres. Dentro desse contexto estão os bosques andino-patagônicos de Araucaria araucana (Pehuén) ao norte de sua distribuição na Argentina. Esses bosques ocupam territórios caracterizados por um acentuado gradiente de precipitação, que vai de cerca de 3000 a 100 milímetros anuais, entre a cordilheira do Andes e a estepe patagônica, que os define como bosques mésicos e xéricos, com diferenças ecológicas que condicionam a formação vegetal, dinâmica, estrutura, relações com o clima e vulnerabilidade em cenários de mudanças ambientais. O objetivo do projeto foi descrever e analisar comparativamente a estrutura anatômica do lenho de 33 espécies arbóreas e arbustivas ocorrentes ao longo de um gradiente de precipitação, entre a encosta da cordilheira dos Andes e a estepe Patagônica, para verificar possíveis alterações anatômicas que permitam a determinação de tendências e elucidem os limites de distribuição das espécies. Foram coletadas amostras não destrutivas de lenho durante três expedições para a Patagônia entre 2012 e 2014, seguidas de procedimentos laboratoriais de confeccção de lâminas histológicas, preparo de amostras para análises dendrocronológicas, captura de imagens com câmeras acopladas a microscópios óptico e eletrônico de varredura, mensurações, descrições e análises comparativas com o auxílio de softwares. Foram identificados caracteres anatômicos exclusivos de sítios secos e úmidos que permitiram a caracterização, posicionamento ao longo do gradiente de precipitação e grupamento de espécies xerófitas e mesófitas; A ultra-estrutura das pontoações de traqueídeos de Araucaria araucana apresentou diferenças marcantes na frequência e porosidade de suas membranas, sendo maior e menos porosas em sítios xéricos, e menor e mais porosas nos mésicos; a chave dicotômica microscópica permitiu a identificação das 32 espécies arbustivas, as espécies Chuquiraga oppositifolia e Nothofagus antarctica apresentaram potencial dendrocronológico, e foram identificadas tendências anatômicas latitudinais influenciadas pelo clima nos extremos da América do Sul. A anatomia do lenho se mostrou uma ferramenta confiável no estudo de um gradiente de precipitação na Patagônia argentina, e os resultados apontam para riscos de embolismos e morte induzida por falha no sistema hidráulico de Araucaria araucana ao longo de todo o gradiente, em função do atual cenário climático, e suas projeções em médio e longo prazos.

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Information on decomposition of harvest residues may assist in the maintenance of soil fertility in second rotation (2R) hoop pine plantations (Araucaria cunninghamii Aiton ex A. Cunn.) of subtropical Australia. The experiment was undertaken to determine the dynamics of residue decomposition and fate of residue-derived N. We used N-15-labeled hoop pine foliage, branch, and stem material in microplots, over a 30-mo period following harvesting. We examined the decomposition of each component both singly and combined, and used C-13 cross-polarization and magic-angle spinning nuclear magnetic resonance (C-13 CPMAS NMR) to chart C transformations in decomposing foliage. Residue-derived N-15 was immobilized in the 0- to 5-cm soil layer, with approximately 40% N-15 recovery in the soil from the combined residues by the end of the 30-mo period. Total recovery of N-15 in residues and soil varied between 60 and 80% for the combined-residue microplots, with 20 to 40% of the residue N-15 apparently lost. When residues were combined within microplots the rate of foliage decomposition decreased by 30% while the rate of branch and stem decomposition increased by 50 and 40% compared with rates for these components when decomposed separately. Residue decomposition studies should include a combined-residue treatment. Based on C-15 CPMAS NMR spectra for decomposing foliage, we obtained good correlations for methoxyl C, aryl C, carbohydrate C and phenolic C with residue mass, N-15 enrichment, and total N. The ratio of carbohydrate C to methoxyl C may be useful as an indicator of harvest residue decomposition in hoop pine plantations.

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Monoculture plantations of Pinus, Eucalyptus and Acacia have been established oil rainforest lands throughout the world. However, this type of reforestation generally supplies low quality timber and contributes to landscape simplification. Alternatives to exotic monoculture plantations are now beginning to gain momentum with farmers and landholders attempting to establish a variety of rainforest trees in small plantations. When compared to the well studied commercial species, knowledge concerning the growth and management of many of these rainforest species is in its infancy. To help expand this limited knowledge base an experimental plantation of 16 rainforest tree species in a randomised design was established near Mt. Mee, in south-eastern Queensland, Australia. Changes in growth, form (based on stem straightness, branch size and branchiness), crown diameters and leaf area of each species were examined over 5 years. Patterns of height growth were also measured monthly for 31 months. Species in this trial could be separated into three groups based on their overall growth after 5 years and their growth patterns. Early successional status, low timber density, high maximum photosynthetic rates and large total leaf areas were generally correlated to rapid height growth. Several species (including Araucaria cunninghamii, Elaeocarpus grandis, Flindersia brayleyana, Grevillea robusta and Khaya nyasica) had above average form and growth, while all species in the trial had considerable potential to have increased productivity through tree selection. As canopy closure occurred at the site between years four and five, growth increments declined. To reduce stand competition a number of different thinning techniques could be employed. However, simple geometric or productivity based thinnings appear to be inappropriate management techniques for this mixed species stand as they would either remove many of the best performing trees or nearly half the species in the trial. Alternatively, a form based thinning would maintain the site's diversity, increase the average form of the plantation and provide some productivity benefits.

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Results from the humid tropics of Australia demonstrate that diverse plantations can achieve greater productivity than monocultures. We found that increases in both the observed species number and the effective species richness were significantly related to increased levels of productivity as measured by stand basal area or mean individual tree basal area. Four of five plantation species were more productive in mixtures with other species than in monocultures, offering on average, a 55% increase in mean tree basal area. A general linear model suggests that species richness had a significant effect on mean individual tree basal area when environmental variables were included in the model. As monoculture plantations are currently the preferred reforestation method throughout the tropics these results suggest that significant productivity and ecological gains could be made if multi-species plantations are more broadly pursued. (c) 2006 Elsevier B.V. All rights reserved.

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The Amazon savannas occur as isolated patches throughout extensive areas of forest in the states of Amapá, Amazonas, Pará, and Roraima. There is a considerable variation in the composition of anuran assemblages in the localities and phytophysiognomies of Amazon savannas and given the absence of studies on reproductive behavior, a systematic and geographically wide sampling has been carried out in the Amapá savanna, located in the Eastern Amazon. The study was conducted in a savanna area in the state of Amapá to examine the composition, ecology, and reproductive behavior of anuran amphibians. We carried out 24 field trips in each phytophysiognomy (gramineous-woody savana, gramineous-herbaceous-woody savana, park savana, and arboreal savanna); for analysis of reproductive behavior observations were made during the period January to December 2013, lasting four consecutive days. Samples were collected by active and acoustic search along 20 plots of 100x50 meters. Twenty-one anuran species were recorded, of which four are new records for the state of Amapá: Dendropsophus walfordi, Scinax fuscomarginatus, Pseudopaludicola boliviana e Elachistocleis helianneae. The KruskalWallis ANOVA revealed significant differences between richness and species diversity in the phytophysiognomies (p < 0.05). The Bray-Curtis similarity coefficient divided the phytophysiognomies into three groups: arboreal savana, gramineous-woody savanna and gramineous-herbaceous-woody savanna, and park savanna. According to the non-metric multidimensional scaling, the structure of the anuran community resulted in a separation into three phytophysiognomies, with significant differences in the structure of communities (ANOSIM, R = 0.823; p < 0.001). In the study of community ecology, the results obtained for spatial, temporal, and trophic niche breadth suggest that the assemblage of anurans of the Amapá savanna is not composed of predominantly generalist species. Also, the presence of other specialist anurans may explain the processes of speciation associated with the isolation of habitats, resulting in heterogeneity and spatial discontinuity in the phytophysiognomies with open formations. The null model analysis revealed that the community is structured based on temporal and trophic niche, indicating a significant influence of contemporary ecological factors on the assemblage. The absence of structure based on spatial niche might be explained by the spatial segregation in the distribution and occupation of anurans in the different phytophysiognomies of the Amapá savanna. Regarding the reproductive behavior of anurans, 11 species were classified as having a long breeding season, intrinsically associated with the rainy season and the reproductive mode of most species that lay egg clutches in lentic water bodies. Six reproductive modes were recorded and parental care was observed in Leptodactylus macrosternum and L. podicipinus, whose reproductive mode is characterized by foam nests. Regarding behavioral reproductive strategies, calling males were observed in all species of anurans, satellite males were recorded only for D. walfordi, Hypsiboas multifasciatus, S. nebulosus and S. fuscomarginatus; active search for females was observed for Phyllomedusa hypochondrialis and L. fuscus, and male displacement was recorded only for Rhinella major and R. margaritifera. Of the reproductive behaviors observed, throat and vocal sac display is associated with courtship and territorial behavior exhibited by males. In addition to courtship behavior, visual signals associated with courtship strategies were recorded for the anurans of the Amapá savanna.

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The Gulf of Carpentaria is an epicontinental sea (maximum depth 70 m) between Australia and New Guinea, bordered to the east by Torres Strait (currently 12 m deep) and to the west by the Arafura Sill (53 m below present sea level). Throughout the Quaternary, during times of low sea-level, the Gulf was separated from the open waters of the Indian and Pacific Oceans, forming Lake Carpentaria, an isolation basin, perched above contemporaneous sea-level with outlet channels to the Arafura Sea. A preliminary interpretation is presented of the palaeoenvironments recorded in six sediment cores collected by the IMAGES program in the Gulf of Carpentaria. The longest core (approx. 15 m) spans the past 130 ka and includes a record of sea-level/lake-level changes, with particular complexity between 80 and 40 ka when sea-level repeatedly breached and withdrew from Gulf/Lake Carpentaria. Evidence from biotic remains (foraminifers, ostracods, pollen), sedimentology and geochemistry clearly identifies a final marine transgression at about 9.7 ka (radiocarbon years). Before this transgression, Lake Carpentaria was surrounded by grassland, was near full, and may have had a surface area approaching 600 km-300 km and a depth of about 15 m. The earlier rise in sea-level which accompanied the Marine Isotopic Stage 6/5 transgression at about 130 ka is constrained by sedimentological and biotic evidence and dated by optical- and thermoluminescence and amino acid racemisation methods.

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The cost management in any organization provides a number of benefits such as security in the good management of resources, but it is little used in the public hospital sector which is shaped like a paradox, facing the complexity of hospital organization and the underfunding situation of Cheers. The purpose of this book was to develop and submit an application method of a costing system in public hospitals. This proposal was developed in partnership with the Secretariat of the State of Paraná Health, with financial support from PPSUS and Araucaria Foundation. The study was conducted as an action research in two public hospitals in Paraná, but it can be replicated in any hospital from the premises of the developed method. For this, We developed the concepts of administration and public governance, the right to health in Brazil, the costs in the public sector and the detailed presentation of the proposed costing system model. The results constitute an important management tool for hospitals and Ministry of Health, enabling greater security leaders in the face of difficulties and challenges in this segment. Thus, it is expected that the book will contribute to governments for better management of public funds allocated to health; with academia, as a still incipient theme in literature; and society, so that more hospitals were professionalize its cost management and thereby provide a more efficient and effective service.

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O estudo teve como objetivo descrever a biologia reprodutiva e a dieta de populações de Thamnodynastes hypoconia em ambientes úmidos subtemperados do extremo sul brasileiro. Para avaliação da reprodução foram feitas análises macroscópicas das gônadas. Para avaliação da ecologia alimentar foram empregadas análises de conteúdo estomacal e de isótopos estáveis (δ13C e δ15N). Os machos apresentaram maior comprimento rostro-cloacal que as fêmeas e atingiram a maturidade sexual com menor tamanho corporal. O ciclo reprodutivo das fêmeas foi sazonal, com vitelogênese secundária ocorrendo entre o inverno e a primavera. Os machos apresentaram ciclo contínuo. Aparentemente a cópula ocorre entre o final da primavera e o início do verão, quando foram detectados embriões nas fêmeas e a parturição ocorreu no verão. Não houve relação entre o tamanho da ninhada e o tamanho da fêmea, e a frequência reprodutiva de 40% foi considerada relativamente baixa. Todavia, por ser uma espécie dominante em banhados subtemperados do extremo sul do Brasil sua estratégia reprodutiva parece ser eficiente. Dessa forma, o ciclo contínuo dos machos, bem como a viviparidade possam potencializar o deslocamento do pico reprodutivo da população de modo a ajustar-se de acordo com os picos de temperatura do ambiente. A análise de conteúdo estomacal mostrou uma dieta predominantemente anurófaga, exceto por um único lagarto. Hylidae foi a família mais representativa, com predomínio de Hypsiboas pulchellus, seguida de Leptodactylidae, onde Leptodactylus latrans teve maior importância. As análises de isótopos estáveis corroboraram a importância dessas espécies na alimentação da serpente. Apesar de ser uma serpente terrestre, T. hypoconia apresentou assinatura isotópica mais próxima das fontes primárias oriundas do ambiente aquático, o que indica a importância das áreas alagáveis para a subsistência de organismos terrestres de habitats adjacentes.

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O presente estudo objetivou conhecer os padrões da composição florística e estrutural do componente arbóreo de um trecho de remanescente de Floresta Ombrófila Mista Montana em Campos Novos - SC e determinar as variáveis ambientais que influenciam estes padrões. Para isso, foi amostrado 1 ha de floresta por meio de 50 parcelas de 10 × 20 m dispostas de forma sistemática, distanciada 30 m entre si, no remanescente florestal. Dentro das parcelas foram identificados e mensurados (circunferência medida a altura do peito, CAP, e altura total) CAP, e altura total) todos os indivíduos arbóreos vivos com CAP ≥ 15,7 cm. Os dados ambientais relacionados às propriedades químicas e físicas dos solos e à topografia também foram coletados em cada parcela. Foram calculados o índice de Shannon-Wiener (H’), a equabilidade de Pielou (J’) e os estimadores fitossociológicos. A organização florístico-estrutural do fragmento foi analisada por meio de uma NMDS (Nonmetric multidimensional scalling). As variáveis ambientais foram ajustadas a posteriori à ordenaçã o produzida, sendo aquelas significativas (p < 0,05) plotadas na forma de vetores. Foram amostrados 1.027 indivíduos, que totalizaram uma área basal de 43,57 m2, distribuídos em 88 espécies e 41 famílias botânicas. A diversidade do remanescente estudado foi relativamente alta (H’=3,59) e a dominância baixa (J’=0,80). A espécie de maior VI foi Araucaria angustifolia (Bertol.) Kuntze (14,44%). A análise multivariada NMDS indicou um gradiente florístico-estrutural relacionado à cota média (altitude), saturação de bases, pH e teores de P nos solos.

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O objetivo desse estudo foi caracterizar a composição florística e a estrutura do componente arbóreo em fragmento de Floresta Ombrófila Mista Alto-Montana e avaliar a influência do efeito de borda sobre a organização, estrutura, riqueza e diversidade de espécies. Foram alocadas 50 parcelas permanentes de 10 x 20 m, divididas em cinco transeções distanciadas, no mínimo, 100 m entre si, em um fragmento florestal, no município de Bom Jardim da Serra - SC. As árvores com circunferência ≥ 15,7 cm na altura do peito (CAP) foram mensuradas (CAP e altura total), identificadas e classificadas quanto às guildas de regeneração (pioneiras, climácicas exigentes em luz e climácicas tolerantes à sombra). Os dados foram analisados por meio dos índices de valor de importância (IVI), NMDS (Nonmetric Multidimensional Scaling), modelo aditivo generalizado e regressões lineares simples. Foram observados 1.457 indivíduos arbóreos, distribuídos em 29 famílias, 43 gêneros e 55 espécies. A espécie com maior valor de importância foi Dicksonia sellowiana Hook. Não foi observada influência do efeito de borda sobre a organização, a estrutura (diâmetro médio, altura média e densidade) da comunidade e participação relativa das guildas de regeneração. No entanto, ficaram evidenciados maiores valores de diversidade, riqueza e equabilidade nas áreas de borda. Desta forma, concluí-se que parte das variações dos valores relativos à diversidade de espécies arbóreas na Floresta Ombrófila Mista Ato-Montana foi determinada pela distância da borda.

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The faunal inventory of the macroinvertebrate community is important to the environmental assessment, since this biota is sensitive to human disturbance. The reservoir of Rio Verde, located on the first plateau of Paraná, is inserted into an agricultural region with several forest fragments Araucaria. The aim of this study was to evaluate the environmental integrity of the reservoir through ecological indexes of macroinvertebrate community benthic and associated with macrophytes. Five sampling points were defined in the study area, which comprise distinct microhabitats in the basin. There were four sampling campaigns, each by weather station: Spring (2014); Summer (2015); Autumn (2015) and Winter (2015). In each sample were measured abiotic various parameters in the field and be collected water samples for nutrient analysis in the laboratory. The macroinvertebrates were collected in triplicate at adapted Macan method using mesh sieve 1 mm and CPUE (catch per unit effort) for 20 minutes. In order to pellet sample was used a dredger model Petersen 2L. Still in the field, by season, samples were collected from macrophytes Myriophyllum aquaticum (Vell) Verdc. and Potamogeton montevidensis A. Benn. in triplicates in the fluvial region of the reservoir, to analyze the associated fractal dimension and macrofauna. For this we used a PVC sampler specific volume 0.025 m3. the following ecological descriptors were calculated in each case: abundance, wealth tax, wealth Margalef, Shannon-Wiener diversity, evenness evenness through the Past software. The index Biological Monitoring Working Party (BMWP) for monitoring sampling points was also calculated. Regarding the statistical analysis, we used the analysis of PERMANOVA to compare points and seasons and canonical correspondence analysis (CCoA) for variables. Regarding M. aquaticum and P. montevidensis it was not verified difference to the average associated macroinvertebrates. However there was a difference for abundance of organisms in the fractal dimension and biomass of specimens. M. aquaticum is more complex and took more macrofauna in relation to P. montevidensis. Regarding the monitoring of the reservoir, it showed up mesotrophic with moderate nutrient concentrations and within the regulatory limits. Benthic macrofauna showed statistical differences in relation to the reservoir region, sample point and temporal variation. The BMWP index showed that the river region has the highest biotic integrity (in all samples above 70 points), and the ecological descriptors of wealth and Margalef diversity of Shannon- Wiener higher. In point 4 (dam downstream) were recorded evidence of possible impacts due to lower wealth and BMWP index which resulted in a questionable quality water. New approaches are needed to focus on the aquatic community in the best understanding of this ecosystem and also with a view to environmental preservation of the Green River Basin.

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Tese (doutorado)—Universidade de Brasília, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Biologia Molecular, 2015.

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Tese (doutorado)—Universidade de Brasília, Instituto de Ciências Sociais, Centro de Pesquisa e Pós-Graduação sobre as Américas, Programa de Pós-Graduação em Estudos Comparados sobre as Américas, 2016.

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El presente proyecto investiga la relación entre las organizaciones con el medio y marketing, para lo cual se debe mencionar el conflicto de intereses de la comunidad y de la organización, y como se intenta percibir a la organización como un buen vecino dentro de la comunidad. A su vez éste estudio cuenta con objetivos basados en la identificación de redes de distribución de petróleo y gas natural, tanto nacionales como internacionales, para así abarcar un sector estratégico más preciso, y mostrar las relación entre las organizaciones y la conformación de comunidades. Se tienen en cuenta factores elementales en el estudio de este sector energético, como son sus principales componentes, así como un marco teórico específico que permita desarrollar el concepto de conformación de comunidades para lograr una exitosa aplicación del mismo. Del mismo modo se incluirán temas relacionados con marketing, pero desde un punto de vista más cercano a la comunidad, tomando los medios y el marketing como un concepto más importante en el impacto de las organizaciones en la comunidad, es decir tomando el concepto de marketing como aquellas comunidades que rodean las organizaciones, como éstas dos interactúan, y que impactos tienen una sobre la otra. De la misma manera se tienen resultados en cuanto a planteamientos más profundos sobre conceptos de marketing que no son desarrollados muy a menudo, los cuales conservan su esencia fundamental y siguen impactando en silencio a las organizaciones, pero que si lo estudiamos y aprovechamos de algún modo lograremos beneficios para nuestra organización y para los intereses colectivos.