104 resultados para patch-mosaic burning


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Recent developments have highlighted the importance of forest amount at large spatial scales and of matrix quality for ecological processes in remnants. These developments, in turn, suggest the potential for reducing biodiversity loss through the maintenance of a high percentage of forest combined with sensitive management of anthropogenic areas. We conducted a multi-taxa survey to evaluate the potential for biodiversity maintenance in an Atlantic forest landscape that presented a favorable context from a theoretical perspective (high proportion of mature forest partly surrounded by structurally complex matrices). We sampled ferns, butterflies, frogs, lizards, bats, small mammals and birds in interiors and edges of large and small mature forest remnants and two matrices (second-growth forests and shade cacao plantations), as well as trees in interiors of small and large remnants. By considering richness, abundance and composition of forest specialists and generalists, we investigated the biodiversity value of matrix habitats (comparing them with interiors of large remnants for all groups except tree), and evaluated area (for all groups) and edge effects (for all groups except trees) in mature forest remnants. our results suggest that in landscapes comprising high amounts of mature forest and low contrasting matrices: (1) shade cacao plantations and second-growth forests harbor an appreciable number of forest specialists; (2) most forest specialist assemblages are not affected by area or edge effects, while most generalist assemblages proliferate at edges of small remnants. Nevertheless, differences in tree assemblages, especially among smaller trees, Suggest that observed patterns are unlikely to be stable over time. (C) 2009 Elsevier Ltd. All rights reserved.

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Fire management ran increase the biomass of some plant species at fire breaks in reserves of the Cerrado. For example, numerous and large patches of monkey-nuts (Anacardium humile, Anacardiaceae) provide abundant food resources for wildlife in the lower strata of savanna woodlands managed by fire. The objective of this study was to examine the exploitation of A. humile patches by birds in managed savanna woodlands (fire breaks) at Emas National Park, southwest Brazil. The relationship between flock size and the size of Anacardium patches were also investigated. Fire breaks were sampled in September and October 2006, when fruits and flowers were abundant. Ara ararauna was often recorded exploiting resources of Anacardium patches. This species and other psittacids (Amazona aestiva, Alipiopsittaca xanthops, and Diopsittaca nobilis) consumed seeds usually on the ground around fruiting patches. Members of Aratinga aurea flocks and Ramphastos toco consumed pseudo-fruits. Larger flocks detected were those of A. aurea and A. ararauna. Groups of A. ararauna that exploited larger patches tended to be larger than flocks that exploited smaller patches. This study suggests that intra- and interspecific interactions and characteristics of Anacardium patches and of the surrounding vegetation are involved in the feeding ecology of birds in the lower stratum of managed woodlands. Fruiting Anacardium patches attract numerous frugivorous birds to fire breaks at Emas National Park. Further research is needed to a better understanding of the influence of fire management on birds in the Cerrado. Accepted 31 July 2009.

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So Paulo is the most developed state in Brazil and contains few fragments of native ecosystems, generally surrounded by intensive agriculture lands. Despite this, some areas still shelter large native animals. We aimed at understanding how medium and large carnivores use a mosaic landscape of forest/savanna and agroecosystems, and how the species respond to different landscape parameters (percentage of landcover and edge density), in a multi-scale perspective. The response variables were: species richness, carnivore frequency and frequency for the three most recorded species (Puma concolor, Chrysocyon brachyurus and Leopardus pardalis). We compared 11 competing models using Akaike`s information criterion (AIC) and assessed model support using weight of AIC. Concurrent models were combinations of landcover types (native vegetation, ""cerrado"" formations, ""cerrado"" and eucalypt plantation), landscape feature (percentage of landcover and edge density) and spatial scale. Herein, spatial scale refers to the radius around a sampling point defining a circular landscape. The scales analyzed were 250 (fine), 1,000 (medium) and 2,000 m (coarse). The shape of curves for response variables (linear, exponential and power) was also assessed. Our results indicate that species with high mobility, P. concolor and C. brachyurus, were best explained by edge density of the native vegetation at a coarse scale (2,000 m). The relationship between P. concolor and C. brachyurus frequency had a negative power-shaped response to explanatory variables. This general trend was also observed for species richness and carnivore frequency. Species richness and P. concolor frequency were also well explained by a second concurrent model: edge density of cerrado at the fine (250 m) scale. A different response was recorded for L. pardalis, as the frequency was best explained for the amount of cerrado at the fine (250 m) scale. The curve of response was linearly positive. The contrasting results (P. concolor and C. brachyurus vs L. pardalis) may be due to the much higher mobility of the two first species, in comparison with the third. Still, L. pardalis requires habitat with higher quality when compared with other two species. This study highlights the importance of considering multiple spatial scales when evaluating species responses to different habitats. An important and new finding was the prevalence of edge density over the habitat extension to explain overall carnivore distribution, a key information for planning and management of protected areas.

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Objective. To investigate the short-term effects of exposure to particulate matter from biomass burning in the Amazon on the daily demand for outpatient care due to respiratory diseases in children and the elderly. Methods. Epidemiologic study with ecologic time series design. Daily consultation records were obtained from the 14 primary health care clinics in the municipality of Alta Floresta, state of Mato Grosso, in the southern region of the Brazilian Amazon, between January 2004 and December 2005. Information on the daily levels of fine particulate matter was made available by the Brazilian National Institute for Spatial Research. To control for confounding factors ( situations in which a non-causal association between exposure and disease is observed due to a third variable), variables related to time trends, seasonality, temperature, relative humidity, rainfall, and calendar effects ( such as occurrence of holidays and weekends) were included in the model. Poisson regression with generalized additive models was used. Results. A 10 mu g/m(3) increase in the level of exposure to particulate matter was associated with increases of 2.9% and 2.6% in outpatient consultations due to respiratory diseases in children on the 6th and 7th days following exposure. Significant associations were not observed for elderly individuals. Conclusions. The results suggest that the levels of particulate matter from biomass burning in the Amazon are associated with adverse effects on the respiratory health of children.

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In the present study Tradescantia pallida micronucleus (Trad-MCN) bioassay was used to assess the genotoxicity of particulate matter with a mass median aerodynamic diameter less than 10 pm (PM(10)) in Tangara da Serra (MT), a Brazilian Amazon region that suffers the impact of biomass burning. The levels of PM (coarse and fine size fractions) and black carbon (BC) collected were also measured. Furthermore, the alkanes and polycyclic aromatic hydrocarbons (PAHs) were identified and quantified in the samples taken during the burning period by gas chromatography with flame ionization detection (GC-FID). The PM and BC results for both fractions indicate a strong correlation (p < 0.001). The analysis of alkanes indicates an anthropic influence. Retene was the most abundant PAH found, an indicator of biomass burning, and 12 other PAHs considered to be potentially mutagenic and/or carcinogenic were identified in this sample. The Trad-MCN bioassay showed a significant increase in micronucleus frequency during the period of most intense burning, possibly related to the mutagenic PAHs that were found in such extracts. This study demonstrated that Trad-MCN was sensitive and efficient in evaluating the genotoxicity of organic compounds from biomass burning. It further emphasizes the importance of performing chemical analysis, because changes in chemical composition generally have a negative effect on many living organisms. This bioassay (ex situ), using T. pallida with chemical analysis, is thus recommended for characterizing the genotoxicity of air pollution. Crown Copyright (C) 2011 Published by Elsevier Inc. All rights reserved.

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This study was conducted at three sites of different characteristics in Sao Paulo State Sao Paulo (SPA), Piracicaba (PRB) and Mate Atlantica Forest (MAT) PM(10), n-alkanes. pristane and phytane, PAHs, water-soluble ions and biomass burning tracers like levoglucosan and retene, were determined in quartz fiber filters. Samplings occurred on May 8th to August 8th, 2007 at the MAT site; on August 15th to 29th in 2007 and November 10th to 29th in 2008 at the PRB site and, March 13th to April 4th in 2007 and August 7th to 29th in 2008 at the SPA site Aliphatic compounds emitted biogenically were less abundant at the urban sites than at the forest site, and its distribution showed the influence of tropical vascular plants Air mass transport front biomass burning regions is likely to impact the sites with specific molecular markers The concentrations of all species were variable and dependent of seasonal changes In the most dry and polluted seasons, n-alkane and canon total concentrations were similar between the megacity and the biomass burning site PAHs and inorganic ion abundances were higher at Sao Paulo than Piracicaba, yet, the site influenced by biomass burning seems lobe the most impacted by the organic anion abundance in the atmosphere Pristane and phytane confirm the contamination by petroleum residues at urban sites, at the MAT site, biological activity and long range transport of pollutants might influence the levels of pristane (C) 2010 Elsevier B V All rights reserved

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Nasal mucociliary system is the first line of defense of the upper airways and may be affected acutely by exposure to particulate matter (PM) from biomass burning. Several epidemiologic studies have demonstrated a consistent association between levels of air pollution from biomass burning with increases in hospitalization for respiratory diseases and mortality. To determine the acute effects of exposure to particulate matter from biomass burning in nasal mucociliary transport by saccharin transit time (STT) test, we studied thirty-three non-smokers and twelve light smokers sugarcane cutters in two periods: pre-harvest season and 4 h after harvest at the first day after biomass burning. Lung function, exhaled carbon monoxide (CO), nasal symptoms questionnaire and mucociliary clearance (MC) were assessed. Exhaled CO was increased in smokers compared to non-smokers but did not change significantly after harvest. In contrast, SIT was similar between smokers and non-smokers and decreased significantly after harvest in both groups (p < 0.001). Exposure to PM from biomass burning did not influence nasal symptoms. Our results suggest that acute exposure to particulate matter from sugarcane burned affects mucociliary clearance in smokers and non-smokers workers in the absence of symptoms. (C) 2011 Elsevier Ltd. All rights reserved.

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Current scientific knowledge provides clear evidence that alcohol-based mouthwashes can be beneficial in a daily oral health routine, including dental hygiene and plaque control. Several issues are worth discussing, in spite of the wealth of supporting evidence. Despite some undesirable effects to some people, like burning sensation, and some contraindications, like the use by infants, alcohol addicts and patients with mucosal injuries, there is no reason to avoid the use of alcohol-containing mouthwashes as long as they are used following proper guidance by dental professionals and the manufacturers' instructions. The alleged correlation between oral cancer and alcohol-based mouthrinses presents so little, weak, inconsistent and even contradictory evidence in the literature that any kind of risk warning to patients would be uncalled for. Antimicrobial mouthrinses are safe and effective in reducing plaque and gingivitis, and should be part of a comprehensive oral health care regimen that includes brushing, flossing and rinsing to prevent or minimize periodontal disease.

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Fire management is a common practice in several reserves in the Cerrado, but its influences on bird reproduction remain unknown. In addition, the nesting biology of the Burrowing Owl (Athene cunicularia) has been studied in numerous environments, but not in tropical grasslands managed by fire. This study examined the effects of fire management on the nesting biology of A. cunicularia in Emas National Park, State of Goias, central Brazilian Cerrado. We compared the number of breeding pairs and their burrows in October and November 2009 at 15 study sites in grasslands managed by fire (firebreaks) and unmanaged grasslands adjacent to and distant from firebreaks. We visited active burrows two-four times and described the burrow entrances and sentinel sites and counted and observed adults and young. A total of 19 burrows were found at firebreaks. One and two burrows were found in grasslands adjacent to and distant from firebreaks, respectively. For all burrows found, one to three young reached the adult size, being able to fly and/or run in early November. The 22 burrows found were in the ground, associated or not with termite and ant nests. Most (86.4%) burrows had only one entrance. Only three burrows had two or three entrances. Structures used as sentinel perches by adults were mounds in front of the burrow entrances, termite nests, shrubs and trees. Most of these sentinel sites were shorter than 2 m high and located less than 10 m from the burrow entrance. At Emas National Park, firebreaks appear to provide more attractive conditions to the nesting of A. cunicularia than unmanaged grasslands, likely because of the short herbaceous stratum due to frequent burning of firebreaks. This study suggests that fire management provides suitable conditions for the successful reproduction of A. cunicularia in firebreaks at Emas National Park.

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We investigated the influence of Pinus afforestation on the structure of leaf-litter ant communities in the southeastern Brazilian Atlantic Forest, studying an old secondary forest and a nearly 30 year-old never managed Pinus elliottii reforested area. A total of 12,826 individual ants distributed among 95 species and 32 genera were obtained from 50 1 m² samples/ habitat. Of these, 60 species were recorded in the pine plantation and 82 in the area of Atlantic forest; almost 50% of the species found in the secondary forest area were also present in the pine plantation. The number of species per sample was significantly higher in the secondary forest than in the pine plantation. Forest-adapted taxa are the most responsible for ant species richness differences between areas, and the pine plantation is richer in species classified as soil or litter omnivorous-dominants. The specialized ant predators registered in the pine plantation, as seven Dacetini, two Basiceros, two Attini and two Discothyrea, belong to widely distributed species. The NMDS (non-metric multidimensional scaling) ordination also suggested strong differences in similarity among samples of the two areas. Furthermore, this analysis indicated higher sample heterogeneity in the secondary forest, with two clusters of species, while in the pine plantation the species belong to a single cluster. We applied the ant mosaic hypothesis to explain the distribution of the leaf-litter fauna and spatial autocorrelation tests among samples. We argue that the results are likely related to differences in quality and distribution of the leaf-litter between the pine plantation and the secondary area.

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A comunidade de mamíferos terrestres foi amostrada em três localidades (1-Mateiros, TO; 2- Rio da Conceição, TO e 3- Formosa do Rio Preto, BA) no interior da Estação Ecológica Serra Geral do Tocantins. Para o registro dos marsupiais e pequenos roedores foram utilizadas armadilhas convencionais (5.396 armadilhas.noite) e armadilhas de queda (5.300 pitfalls.noite) nas diferentes fitofisionomias encontradas, entre elas: campo úmido, campo limpo, campo sujo, campo cerrado, cerrado sensu stricto, cerrado com afloramentos rochosos, mata de galeria e mata de galeria úmida. No caso dos mamíferos de médio e grande porte, foram obtidos registros casuais através de observação direta e evidências indiretas (rastros, fezes, crânios e carcaças de animais encontrados mortos). Foram amostradas 24 espécies de pequenos mamíferos e 17 espécies de mamíferos de médio e grande porte, totalizando 41 espécies para a região. Considerando-se os pequenos mamíferos, a comunidade foi representada por várias espécies raras e de abundância intermediária, e poucas espécies muito abundantes. Os roedores cricetídeos dominaram tanto em número de espécies (14) quanto em abundância (50% da comunidade). As espécies se distribuíram, basicamente, em dois tipos de fisionomias: um grupo esteve restrito aos ambientes florestais, e outro às formações abertas, demonstrando a grande seletividade de hábitats e a importância de se amostrar o mosaico de hábitats presente na região para uma melhor caracterização da diversidade deste grupo de mamíferos. Em termos biogeográficos, a fauna de pequenos mamíferos amostrada apresentou certa sobreposição com a fauna da Caatinga e da Amazônia, evidenciando a importância destes domínios para a composição de espécies das comunidades que habitam a porção norte do Cerrado, além da presença de espécies endêmicas e de distribuição geográfica restrita ao norte do domínio, caracterizando uma comunidade distinta de outras regiões do Cerrado. Em relação aos mamíferos de médio e grande porte, a presença de um elevado número de espécies ameaçadas de extinção (10) também ressalta a importância da preservação desta região.

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OBJECTIVE: To analyze the impact on human health of exposure to particulate matter emitted from burnings in the Brazilian Amazon region. METHODS: This was an ecological study using an environmental exposure indicator presented as the percentage of annual hours (AH%) of PM2.5 above 80 μg/m3. The outcome variables were the rates of hospitalization due to respiratory disease among children, the elderly and the intermediate age group, and due to childbirth. Data were obtained from the National Space Research Institute and the Ministry of Health for all of the microregions of the Brazilian Amazon region, for the years 2004 and 2005. Multiple regression models for the outcome variables in relation to the predictive variable AH% of PM2.5 above 80 μg/m3 were analyzed. The Human Development Index (HDI) and mean number of complete blood counts per 100 inhabitants in the Brazilian Amazon region were the control variables in the regression analyses. RESULTS: The association of the exposure indicator (AH%) was higher for the elderly than for other age groups (β = 0.10). For each 1% increase in the exposure indicator there was an increase of 8% in child hospitalization, 10% in hospitalization of the elderly, and 5% for the intermediate age group, even after controlling for HDI and mean number of complete blood counts. No association was found between the AH% and hospitalization due to childbirth. CONCLUSIONS: The indicator of atmospheric pollution showed an association with occurrences of respiratory diseases in the Brazilian Amazon region, especially in the more vulnerable age groups. This indicator may be used to assess the effects of forest burning on human health.

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The objective of the study is to evaluate the effect of the daily variation in concentrations of fine particulate matter (diameter less than 2.5µm - PM2.5) resulting from the burning of biomass on the daily number of hospitalizations of children and elderly people for respiratory diseases, in Alta Floresta and Tangará da Serra in the Brazilian Amazon in 2005. This is an ecological time series study that uses data on daily number of hospitalizations of children and the elderly for respiratory diseases, and estimated concentration of PM2.5. In Alta Floresta, the percentage increases in the relative risk (%RR) of hospitalization for respiratory diseases in children were significant for the whole year and for the dry season with 3-4 day lags. In the dry season these measurements reach 6% (95%CI: 1.4-10.8). The associations were sig-nificant for moving averages of 3-5 days. The %RR for the elderly was significant for the current day of the drought, with a 6.8% increase (95%CI: 0.5-13.5) for each additional 10µg/m3 of PM2.5. No as-sociations were verified for Tangara da Serra. The PM2.5 from the burning of biomass increased hospitalizations for respiratory diseases in children and the elderly.

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The present work has aimed to determine the 16 US EPA priority PAH atmospheric particulate matter levels present in three sites around Salvador, Bahia: (i) Lapa bus station, strongly impacted by heavy-duty diesel vehicles; (ii) Aratu harbor, impacted by an intense movement of goods, and (iii) Bananeira village on Maré Island, a non vehicle-influenced site with activities such as handcraft work and fisheries. Results indicated that BbF (0.130-6.85 ng m-3) is the PAH with highest concentration in samples from Aratu harbor and Bananeira and CRY (0.075-6.85 ng m-3) presented higher concentrations at Lapa station. PAH sources from studied sites were mainly of anthropogenic origin such as gasoline-fueled light-duty vehicles and diesel-fueled heavy-duty vehicles, discharges in the port, diesel burning from ships, dust ressuspension, indoor soot from cooking, and coal and wood combustion for energy production.

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OBJETIVO: Estimar a prevalência de sintomas respiratórios e analisar fatores associados, bem como medidas de pico de fluxo expiratório em escolares. MÉTODOS: Estudo descritivo transversal com escolares de dez a 14 anos de Monte Aprazível, SP. Foram aplicados questionários sobre sintomas de asma e de rinite do protocolo International Study of Asthma and Allergies in Childhood, questões sociodemográficas, fatores predisponentes e antecedentes pessoais e familiares. Foram realizadas medidas repetidas do pico de fluxo expiratório nas crianças e dos níveis de concentração de material particulado (MP2,5) e de black carbon. RESULTADOS: A prevalência de sintomas de asma foi de 11% e de 33,2% de rinite; 10,6% apresentaram mais de quatro crises de sibilos nos últimos 12 meses. Antecedentes familiares para bronquite e rinite associaram-se à presença de asma (p = 0,002 e p < 0,001) e de rinite atuais (p < 0,001 e p < 0,001, respectivamente). Para rinite, houve associação com presença de mofo ou rachadura na casa (p = 0,009). Houve maior freqüência de rinite nos meses de junho a outubro, período de safra da cana de açúcar. Prevalência diária de pico de fluxo expiratório abaixo de 20% da mediana de medidas na criança foi maior em dias com maior concentração de MP2,5. CONCLUSÕES: A prevalência de sintomas de asma está abaixo e a de rinite está acima da média nacional. Ainda que dentro dos níveis aceitáveis, a poluição nos períodos de queima da palha da cana-de-açúcar pode contribuir para a exacerbação de episódios de asma e de rinite.