348 resultados para arboreal ecotopes


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O objetivo do trabalho foi identificar a fauna flebotomínea em áreas do perímetro urbano do município de Bonito, Mato Grosso do Sul, Brasil. O estudo foi desenvolvido de março de 2005 a fevereiro de 2006, em 17 ecótopos distribuídos em 12 locais, três no Centro e nove em diferentes bairros. As capturas foram realizadas quinzenalmente com armadilhas automáticas luminosas. Capturou-se 2.680 espécimes, 2.283 machos e 397 fêmeas, de 12 espécies, Brumptomyia avellari, Brumptomyia brumpti, Bichromomyia flaviscutellata, Evandromyia corumbaensis, Evandromyia sallesi, Lutzomyia longipalpis, Micropygomyia acanthopharynx, Micropygomyia quinquefer, Nyssomyia whitmani, Psathyromyia aragaoi, Psathyromyia punctigeniculata e Psathyromyia shannoni. Lutzomyia longipalpis, vetora do agente da leishmaniose visceral americana, foi a espécie mais freqüente e a mais abundante, representando 93,5% dos flebotomíneos capturados e índice de abundância padronizado de 0,85. Com freqüência mais expressiva nos ecótopos próximos de galinheiro e de pocilga, esta espécie foi capturada em todos os meses do ano, com picos no verão, inverno e primavera. As demais espécies foram pouco freqüentes. Ressalta-se que a captura de Bichromomyia flaviscutellata, no intradomicilio e peridomicílio, nas proximidade de mata remanescente, tem grande significado epidemiológico uma vez que essa espécie é a principal vetora da Leishmania (Leishmania) amazonensis, agente etiológico da leishmaniose cutânea difusa anérgica. Portanto, na área urbana de Bonito foram encontradas duas espécies que comprovadamente participam da transmissão de leishmanioses, Lutzomyia longipalpis e Bichromomyia flaviscutellata, ambas encontradas naturalmente infectadas pelos respectivos agentes.

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Byrsonima basiloba A. Juss. species is a native arboreal type from the Brazilian ""cerrado"" (tropical American savanna), and the local population uses it to treat diseases, such as diarrhea and gastric ulcer. It belongs to the Malpighiaceae family, and it is commonly known as ""murici."" Considering the popular use of B. basiloba derivatives and the lack of pharmacological potential studies regarding this vegetal species, the mutagenic and antimutagenic effect of methanol (MeOH) and chloroform extracts were evaluated by the Ames test, using strains TA97a, TA98, TA100, and TA102 of Salmonella typhimurium. No mutagenic activity was observed in any of the extracts. To evaluate the antimutagenic potential, direct and indirect mutagenic agents were used: 4 nitro-o-phenylenediamine, sodium azide, mitomycin C, aflatoxin B(1), benzo[a] pyrene, and hydrogen peroxide. Both the extracts evaluated showed antimutagenic activity, but the highest value of inhibition level (89%) was obtained with the MeOH extract and strain TA100 in the presence of aflatoxin B(1). Phytochemical analysis of the extracts revealed the presence of n-alkanes, lupeol, ursolic and oleanolic acid, (+)-catechin, quercetin- 3-O-alpha-L-arabinopyranoside, gallic acid, methyl gallate, amentoflavone, quercetin, quercetin-3-O-(2 ''-O-galloyl)-beta-D-galactopyranoside, and quercetin-3-O-(2 ''-O-galloyl)-alpha-L-arabinopyranoside.

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Rainfall interception by the two most usual species in forest urban spaces was analysed by measuring of interception (I) or interception losses, through fall (PI), stem flow (Et) and gross precipitation (PT). The chosen species were Caesalpinia pluviosa DC. (Fabaceae: Caesalpinoideae) or sibipiruna, and Tipuana tipu O. Kuntze (Fabaceae: Faboideae) or tipuana. The individuals analysed were more than 50 years old, with three separate individuals and three individuals in each studied group of species at the campus of ""Luiz de Queiroz"" College of Agriculture (University of Sao Paulo), Piracicaba. The experiments were carried out from January to February 2007. Water was collected using seven-litre pails, in the edges and in the centre of the canopies. A high correlation of Th with Pg was observed on the centre of the crow of tipuana and by the edges of sibipiruna. Stand! had low correlation with Pg for both species. The average of rain interception was greater in the edges of the crow of sibipiruna individuals, 60.6%, and in the centre of tipuana crow, 59.40%. Thus, both species intercepted up to 60% of the water rainfall, which indicates a great potential of both species for arborisation in urban environments.

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Northeastern Brazil represents a strategic area in terms of Quaternary records of environmental changes in South America due to its distinct semi-arid climate in near equatorial latitudes. In this study, carbon isotope and charcoal distribution records in soils are used to characterize vegetation dynamics, forest fires and their relation to climate change since the Late Pleistocene in the States of Ceara, Piaui and Paraiba, Northeastern Brazil. At the Ceara site, the carbon isotope record showed an enrichment trend from -24%(o) to 19%(o) during the early-mid Holocene, indicating an opening of vegetation and expansion of savanna vegetation (C(4) plants) during this period. A trend toward more depleted delta(13)C values (similar to-32%.) in the late Holocene indicates an expansion of forest vegetation (C(3) plants). A similar trend is observed at the Piaui and Paraiba sites where values of similar to-24%0 are associated with open forest vegetation during the late Pleistocene. In the early-mid Holocene, delta(13)C values of up to -18.0%(o), suggest the expansion of C4 plants. Based on the carbon isotope data, it is postulated that from similar to 18,000 cal yr B.P. to similar to 11,800 cal yr B.P.-similar to 10,000 cal yr B.P. arboreal vegetation was dominant in northeastern Brazil and is associated with humid climates. The savanna expanded from similar to 10,000 cal yr B.P. to similar to 4500-3200 cal yr B.P. due to a less humid/drier climatic phase, also supported by the significant presence of fires (charcoal fragments in the soil). From approximately 3200-2000 cal yr B.P. to the present, carbon isotope records suggest forest expansion and a more humid phase. These results form part of a regional pattern since they are in agreement with paleovegetation records obtained in regions of Maranhao, northeastern Brazil and in the Amazon and Rondonia States, northern Brazil. (C) 2010 Elsevier B.V. All rights reserved.

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Rare species are one of the principal components of the species richness and diversity encountered in Dense Ombrophilous Tropical Forests. This study sought to analyze the rare canopy species within the Atlantic Coastal Forest in Rio de Janeiro State, Brazil. Six different communities were examined: Dense Ombrophilous alluvial Forest; Dense sub-montane Ombrophilous Forest; Dense Montane Ombrophilous in Serra do Mar and Serra da Mantiqueira. In each area the vegetation was sampled within forty 10 x 25 m plots alternately distributed along a linear transect. All trees with DBH (1.3 m above ground level) a parts per thousand yen5 cm were sampled. The canopy was characterized using the allometric relationship between diameter and height, and included all trees with BDH a parts per thousand yen10 cm and height a parts per thousand yen10 m. A total of 64 families, 206 genera, and 542 species were sampled, of which 297 (54.8%) represented rare species (less than one individual per hectare). The percentage of rare species varied from 34 to 50% in each of the different communities sampled. A majority of these rare trees belonged to the Rosidae, and a smaller proportion to the Dilleniidae. It was concluded that there was no apparent pattern to rarity among families, that rarity was probably derived from a number of processes (such as gap formation), and that a great majority of the rare species sampled were consistently rare. This indicates that the restricted geographic distribution and high degree of endemism of many arboreal taxa justifies the conservation of even small fragments of Atlantic Forest.

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We describe in this paper a new genus and species of cricetid rodent from the Atlantic Forest of Brazil, one of the most endangered eco-regions of the world. The new form displays some but not all synapomorphies of the tribe Oryzomyini, but a suite of unique characteristics is also observed. This new forest rat possesses anatomical characteristics of arboreal taxa, such as very developed plantar pads, but was collected almost exclusively in pitfall traps. Phylogenetic analyses of morphological (integument, soft tissue, cranial, and dental characters) and molecular [nuclear - Interphotoreceptor retinoid binding protein (Irbp) - and mitochondrial - cytochrome b - genes] datasets using maximum likelihood and cladistic parsimony approaches corroborate the inclusion of the new taxon within oryzomyines. The analyses also place the new form as sister species to Eremoryzomys polius, an Andean rat endemic to the Maranon valley. This biogeographical pattern is unusual amongst small terrestrial vertebrates, as a review of the literature points to few other similar examples of Andean-Atlantic Forest pairings, in hylid frogs, Pionus parrots, and other sigmodontine rodents. (C) 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 161, 357-390. doi:10.1111/j.1096-3642.2010.00643.x

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There is a great need of research to assess the behavior of micronutrients in natural forests of southern Brazil. Do to this need, the objective of this work was to study the levels and amounts of micronutrients in forest above ground biomass of the forest, in a comparative way, in two secondary succession stages (SSS) in a Seasonal Deciduous Forest in Rio Grande do Sul, Brazil. The SSS had enjoyed 35 and 55 years of regeneration since the end of agricultural use, respectively for initial secondary forest (ISF) and late secondary forest (LSF). The above-ground biomass was collected and separated into vegetative strata and these in fractions, thereafter chemically analyzed for the levels of B, Fe, Zn, Mn and Cu. Leaf fractions of arboreal, shrubs and herbaceous strata showed the highest levels for most nutrients. Only the levels of iron and manganese were higher in the bark fraction, for both sucession stages. In the LSF, the herbaceous stratum also showed high levels of Fe. The average levels of micronutrients showed differences between the two sucession stages only in relation to Fe and Mn, with higher levels in LSF biomass. The amount of nutrients stored was always higher in LSF, because of the largest biomass and the higher levels of Fe and Mn in the biomass of this SSS. The quantitative order of nutrient storage in biomass was Fe> Mn> Zn> B> Cu.

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We use a spatially explicit population model to explore the population consequences of different habitat selection mechanisms on landscapes with fractal variation in habitat quality. We consider dispersal strategies ranging from random walks to perfect habitat selectors for two species of arboreal marsupial, the greater glider (Petauroides volans) and the mountain brushtail possum (Trichosurus caninus). In this model increasing habitat selection means individuals obtain higher quality territories, but experience increased mortality during dispersal. The net effect is that population sizes are smaller when individuals actively select habitat. We find positive relationships between habitat quality and population size can occur when individuals do not use information about the entire landscape when habitat quality is spatially autocorrelated. We also find that individual behaviour can mitigate the negative effects of spatial variation on population average survival and fecundity. (C) 1998 Elsevier Science Ltd. All rights reserved.

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Wildlife-habitat models are an important tool in wildlife management toda?, and by far the majority of these predict aspects of species distribution (abundance or presence) as a proxy measure of habitat quality. Unfortunately, few are tested on independent data, and of those that are, few show useful predictive st;ill. We demonstrate that six critical assumptions underlie distribution based wildlife-habitat models, all of which must be valid for the model to predict habitat quality. We outline these assumptions in a mete-model, and discuss methods for their validation. Even where all sis assumptions show a high level of validity, there is still a strong likelihood that the model will not predict habitat quality. However, the meta-model does suggest habitat quality can be predicted more accurately if distributional data are ignored, and variables more indicative of habitat quality are modelled instead.

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1. Although population viability analysis (PVA) is widely employed, forecasts from PVA models are rarely tested. This study in a fragmented forest in southern Australia contrasted field data on patch occupancy and abundance for the arboreal marsupial greater glider Petauroides volans with predictions from a generic spatially explicit PVA model. This work represents one of the first landscape-scale tests of its type. 2. Initially we contrasted field data from a set of eucalypt forest patches totalling 437 ha with a naive null model in which forecasts of patch occupancy were made, assuming no fragmentation effects and based simply on remnant area and measured densities derived from nearby unfragmented forest. The naive null model predicted an average total of approximately 170 greater gliders, considerably greater than the true count (n = 81). 3. Congruence was examined between field data and predictions from PVA under several metapopulation modelling scenarios. The metapopulation models performed better than the naive null model. Logistic regression showed highly significant positive relationships between predicted and actual patch occupancy for the four scenarios (P = 0.001-0.006). When the model-derived probability of patch occupancy was high (0.50-0.75, 0.75-1.00), there was greater congruence between actual patch occupancy and the predicted probability of occupancy. 4. For many patches, probability distribution functions indicated that model predictions for animal abundance in a given patch were not outside those expected by chance. However, for some patches the model either substantially over-predicted or under-predicted actual abundance. Some important processes, such as inter-patch dispersal, that influence the distribution and abundance of the greater glider may not have been adequately modelled. 5. Additional landscape-scale tests of PVA models, on a wider range of species, are required to assess further predictions made using these tools. This will help determine those taxa for which predictions are and are not accurate and give insights for improving models for applied conservation management.

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Analysis of charred plant macro-remains, including wood charcoals, cereals, seeds, tubers and fruits from the Neolithic site of Catalhoyuk has indicated complex patterns of plant resource use and exploitation in the Konya plain during the early Holocene. Evidence presented in this paper shows that settlement location was not dictated by proximity to high quality arable land and direct access to arboreal resources (firewood, timber, fruit producing species). A summary of the patterns observed in sample composition and species representation is outlined here together with preliminary interpretations of these results within their broader regional context.

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Accurate habitat mapping is critical to landscape ecological studies such as required for developing and testing Montreal Process indicator 1.1e, fragmentation of forest types. This task poses a major challenge to remote sensing, especially in mixedspecies, variable-age forests such as dry eucalypt forests of subtropical eastern Australia. In this paper, we apply an innovative approach that uses a small section of one-metre resolution airborne data to calibrate a moderate spatial resolution model (30 m resolution; scale 1:50 000) based on Landsat Thematic Mapper data to estimate canopy structural properties in St Marys State Forest, near Maryborough, south-eastern Queensland. The approach applies an image-processing model that assumes each image pixel is significantly larger than individual tree crowns and gaps to estimate crown-cover percentage, stem density and mean crown diameter. These parameters were classified into three discrete habitat classes to match the ecology of four exudivorous arboreal species (yellowbellied glider Petaurus australis, sugar glider P. breviceps, squirrel glider P. norfolcensis , and feathertail glider Acrobates pygmaeus), and one folivorous arboreal marsupial, the greater glider Petauroides volans. These species were targeted due to the known ecological preference for old trees with hollows, and differences in their home range requirements. The overall mapping accuracy, visually assessed against transects (n = 93) interpreted from a digital orthophoto and validated in the field, was 79% (KHAT statistic = 0.72). The KHAT statistic serves as an indicator of the extent that the percentage correct values of the error matrix are due to ‘true’ agreement verses ‘chance’ agreement. This means that we are able to reliably report on the effect of habitat loss on target species, especially those with a large home range size (e.g. yellow-bellied glider). However, the classified habitat map failed to accurately capture the spatial patterning (e.g. patch size and shape) of stands with a trace or sub-dominance of senescent trees. This outcome makes the reporting of the effects of habitat fragmentation more problematic, especially for species with a small home range size (e.g. feathertail glider). With further model refinement and validation, however, this moderateresolution approach offers an important, cost eff e c t i v e advancement in mapping the age of dry eucalypt forests in the region.

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Os roedores Echimyidae tem distribuição Neotropical e são a família mais diversa de roedores Caviomorpha. Apesar da grande diversidade, pouco se sabe sobre a distribuição geográfica, história natural e evolução de vários grupos de equimídeos. O histórico taxonômico dessa família é confuso, sendo alguns grupos raramente coletados e, consequentemente, inferências sobre aspectos evolutivos e biológicos são pouco conclusivas e limitadas à análise de poucos exemplares. Filogenias moleculares não corroboram a classificação taxonômica para a família baseada em dados morfológicos, evidenciando a complexidade da história evolutiva desse grupo. Na Mata Atlântica são registrados cinco gêneros de Echimyidae: o rato-do-bambu, Kannabateomys; os arborícolas Phyllomys e Callistomys; o terrestre Trinomys, e o semi-fossorial Euryzygomatomys. O presente trabalho se baseou na utilização de sequências de DNA para abordar aspectos da evolução e filogenia de roedores equimídeos da Mata Atlântica em três níveis taxonômicos: família, gênero e espécie. O primeiro capítulo aborda a posição filogenética do gênero Callistomys dentro da família, utilizando sequências de 1 marcador mitocondrial (CitB) e 3 nucleares (GHR, RAG1 e vWF). Os resultados mostram que Callistomys forma um clado com o ratão-do-banhado (Myocastor), roedor semi-aquático das regiões abertas no cone sul da América do Sul e com o rato-de-espinho terrestre Proechimys com ocorrência na Amazônia. Esse clado é irmão de Thrichomys, um equimídeo terrestre que ocupa as áreas secas do centro da América do Sul. O agrupamento encontrado é inesperado, uma vez que seus membros apresentam aspectos morfológico, ecológicos e distribuição geográfica distintos e contrastantes. A filogenia resultante indica que Callistomys não é proximamente relacionado aos outros equimídeos arborícolas e sugere que o hábito arborícolas evoluiu mais de uma vez na família. O segundo capítulo investiga aspectos da filogenia, evolução e limites entre espécies de Phyllomys utilizando dois marcadores mitocondriais (CitB e COI) e três nucleares (GHR, RAG1 e vWF). Foram identificados três grupos principais de espécies: um com distribuição longitudinal pela porção central da Mata Atlântica (P. pattoni (P. mantiqueirensis, Phyllomys sp. 4)); e a partir daí dois outros grupos, um com distribuição na porção norte da Mata Atlântica (Phyllomys sp. 2 (P. blainvilii (P. brasiliensis, P. lamarum))); e outro na porção sul (Phyllomys sp. 3 ((Phyllomys sp. 1, P. lundi), (Phyllomys sp. 5 (P. dasythrix (P. nigrispinus (P. sulinus, Phyllomys sp. 6)))))). Foram identificadas duas linhagens independentes representando possíveis espécies novas, elevando o potencial número de espécies do gênero de 17 para 19. As filogenias associadas aos dados de distribuição geográfica sugerem que a diversificação e distribuição das espécies de Phyllomys foi influenciada pela ação conjunta de vários fatores como atividade neotectônica, gradientes altitudinais e latitudinais e mudanças climáticas que atuaram desde o Mioceno, marcando os primeiros eventos de diversificação do gênero até as especiações mais recentes, no Pleistoceno. O terceiro capítulo avalia a variação genética, distribuição geográfica e status taxonômico da espécie Euryzygomaotmys spinosus utilizando dois marcadores mitocondriais (CitB e D-loop). Os resultados mostraram que E.spinosus apresenta distribuição em áreas de Mata Atlântica e adjacências ao sul do Rio Doce, no Brasil, Paraguai e Argentina, incluindo um registro confirmado no Cerrado. A espécie ocupa habitats muito diversos e pode ser considerada generalista. As populações são geneticamente estruturadas ao longo da sua distribuição e os dados genéticos corroboram a taxonomia atual que considera apenas uma espécie, E. spinosus, para o gênero.

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O gênero Guerlinguetus, pertencente à família Sciuridae, possui sete espécies existentes no Brasil. Essas espécies têm sido tratadas como sinônimos de Sciurus aestuans, mas foram distinguidas em um gênero próprio com base nas revisões taxonômicas mais abrangentes disponíveis até recentemente. Apesar disso, pouco há na literatura sobre a distribuição das espécies desse gênero no Brasil e nenhuma pesquisa visando o conhecimento de sua distribuição futura havia sido realizada. A modelagem de distribuição potencial de espécies tem se tornado um componente importante dos planos de conservação e uma grande quantidade de técnicas têm sido desenvolvidas com esta finalidade. Ela pode ser uma ferramenta importante para determinar o grau de ameaça principalmente em espécies ou grupos com poucas informações disponíveis sobre sua distribuição. Com isso, o objetivo do presente trabalho foi verificar a influência das possíveis mudanças climáticas na distribuição das espécies de Guerlinguetus no Brasil, através da modelagem potencial das distribuições atual e futura dessas espécies. Para isso foram utilizados dados climáticos e topográficos e o cenário pessimista de emissão de CO2 (A2) para o ano 2070, do Modelo de Circulação Geral CSIRO, com base no quarto relatório do Painel Intergovernamental de Mudanças Climáticas. Os modelos gerados apresentaram perda significativa de áreas consideradas ambientalmente adequadas, do modelo de distribuição atual para o modelo de distribuição futura para as espécies de Guerlinguetus, com exceção de G. aestuans. Apesar da expansão da região potencial de distribuição de G. aestuans para o ano de 2070, a média dos valores de adequabilidade ambiental diminuiu em relação ao modelo de distribuição atual. A localização dessas espécies de hábito arborícola em áreas geograficamente espalhadas dentro da Amazônia, Cerrado e Mata Atlântica é preocupante, devido a grande perda de área original desses biomas, tornando possível a hipótese de ameaça à sobrevivência das espécies devido a mudanças ambientais futuras.

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The BALA project (Biodiversity of Arthropods of Laurisilva of the Azores) is a research initiative to quantify the spatial distribution of arthropod biodiversity in native forests of the Azores archipelago. Arthropods were collected using a combination of two techniques, targeting epigean (ground dwelling) and canopy (arboreal) arthropods: pitfall traps (with Turquin and Ethylene solutions) and beating samples (using the three most dominant plant species). A total of 109 transects distributed amongst 18 forest fragments in seven of the nine Azorean islands were used in this study. The performance of alternative sampling methods and effort were tested. No significant differences were found in the accumulated number of species captured whether an alternative method was used or whether another transect with similar effort was established in another location within the same fragment. A combination of Ethylene and Turquin traps captured more species per individual, Turquin and beating captured more species per sample, and Turquin captured more species per unit time. An optimization exercise was performed and we found that the protocol applied during recent years is very close to optimal, allowing its future replication with confidence. The minimum combinations of sampling effort and methods, in order to monitor or to inventory diversity, taking into account different proportions of sample completeness are discussed.