997 resultados para Brazilian Forest Act


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IntroductionInsects have been described as mechanical vectors of nosocomial infections.MethodsNon-biting flying insects were collected inside a pediatric ward and neonatal-intensive care unit (ICU) of a Brazilian tertiary hospital.ResultsMost (86.4%) of them were found to carry one or more species of bacteria on their external surfaces. The bacteria isolated were Gram-positive bacilli (68.2%) or cocci (40.9%), and Gram-negative bacilli (18.2%).ConclusionsInsects collected inside a hospital were carrying pathogenic bacteria; therefore, one must consider the possibility they may act as mechanical vectors of infections, in especially for debilitated or immune-compromised patients in the hospital environments where the insects were collected.

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Studies were made of the intestinal parasites of Amerindian populations of the Uaupes River basin of Brazil. Three groups were sampled: 1) Tukano fisher-agriculturalists who live in permanent riverine villages; 2) Maku hunter-horticulturalists who live in close contact with the Tukano fishing villages; and 3) Maku who inhabit the forest interior and have little contact with permanent settlements. Fecal samples were collected from 498 individuals of which 220 were from the first group, 135 from de second and 143 from the third. The samples were analyzed by means of microflotation and centrifugal sedimentation. A total of 18 protozoan and helminth species were recorded based on the presence of cysts or eggs. These included five nematode species that could not be identified. The three common pathogenic nematodes were found to be prevalent: the hookworm, Necator americanus(96%); the whipworm, Trichuris trichiura(77%) and the large roundworm, Ascaris lumbricoides(75%). The prevalence of Ascarisamong the villages was found to vary from 56 to 100%. Individuals living in, or associated with, permanent settlements had higher prevalence and intensity rates than those living in the nomadic hunter-gatherer way. This is shown to be directly related to fecal contamination of the environment in and around permanent settlements. The prevalence of Ascarisin a population can be used as an indicator of such environmental contamination.

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Many texture measures have been developed and used for improving land-cover classification accuracy, but rarely has research examined the role of textures in improving the performance of aboveground biomass estimations. The relationship between texture and biomass is poorly understood. This paper used Landsat Thematic Mapper (TM) data to explore relationships between TM image textures and aboveground biomass in Rondônia, Brazilian Amazon. Eight grey level co-occurrence matrix (GLCM) based texture measures (i.e., mean, variance, homogeneity, contrast, dissimilarity, entropy, second moment, and correlation), associated with seven different window sizes (5x5, 7x7, 9x9, 11x11, 15x15, 19x19, and 25x25), and five TM bands (TM 2, 3, 4, 5, and 7) were analyzed. Pearson's correlation coefficient was used to analyze texture and biomass relationships. This research indicates that most textures are weakly correlated with successional vegetation biomass, but some textures are significantly correlated with mature forest biomass. In contrast, TM spectral signatures are significantly correlated with successional vegetation biomass, but weakly correlated with mature forest biomass. Our findings imply that textures may be critical in improving mature forest biomass estimation, but relatively less important for successional vegetation biomass estimation.

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In Brazilian Amazonia, 20 genera and more than 200 species of polistine wasps are recorded. Local faunas with 70 to 80 species are usually found in non floodable forest environments. However, a variety of wetlands exist in the region, the most expressive in surface area being varzea systems. In this paper, information is presented on polistines from two areas of wetlands in the Brazilian states of Amazonas and Amapá. These are reciprocally compared and also with nearby terra firme locations. Collecting methods consisted of active search for nests, handnetting and automatic trapping of individuals. Forty-six species of 15 genera were collected in Mamirauá, AM, most being widespread common wasps. However, five species deserve special mention in virtue of rarity and/or restricted distribution: Metapolybia rufata, Chartergellus nigerrimus, Chartergellus punctatior, Clypearia duckei, and Clypearia weyrauchi. In Região dos Lagos, AP, 31 species of 9 genera were collected, nearly all being common species with the exception of some Polistes, like P. goeldi and P. occipitalis. Even though less rich than vespid faunas from terra firme habitats, the Mamirauá fauna proved to be quite expressive considering limitations imposed by the hydrological regime. In Região dos Lagos, however, the very low diversity found was below the worst expectations. The virtual absence of otherwise common species in environments like tidal varzea forests along Araguari River is truly remarkable. The causes of low diversity are probably related to isolation and relative immaturity of the region, allied to strong degradation of forested habitats.

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The Amazon rainforest stretches across more than six million square kilometers and nine countries. Of the original forest area it is thought that 18 per cent has been cleared, mainly for farming purposes. In Brazil, the main drivers of deforestation are beef ranching and soya production that together occupy more than 75 per cent of newly deforested land. The situation in the Amazon illustrates a fundamental dilemma facing environmentalists around the world: how to reconcile economic development with biodiversity conservation. In this paper the representation of this dilemma in the British and Brazilian news media is assessed. The results indicate that there were far more articles referring to deforestation in the Brazilian press (816 Brazilian to 29 UK) but that many of these make no mention of what factors are responsible for deforestation. The patterns of representation of the proximate (direct) causes of Amazonian deforestation were very similar in the two countries, with soya and beef cattle ranching commanding the most press attention. The ultimate (indirect) causes of deforestation, however, are treated very differently, with the Brazilian media seemingly far more aware of the role of economic development needs than the UK press. Interestingly, the role of international demand for soya, beef, and forest products in driving deforestation was highlighted primarily in the UK press. These findings are critically discussed in the context of media influence on public understandings of Amazonian deforestation.

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Construction of hydroelectric dams in tropical regions has been contributing significantly to forest fragmentation. Alterations at edges of forest fragments impact plant communities that suffer increases in tree damage and dead, and decreases in seedling recruitment. This study aimed to test the core-area model in a fragmented landscape caused by construction of a hydroelectric power plant in the Brazilian Amazon. We studied variations in forest structure between the margin and interiors of 17 islands of 8-100 hectares in the Tucuruí dam reservoir, in two plots (30 and >100m from the margin) per island. Mean tree density, basal area, seedling density and forest cover did not significantly differ between marginal and interior island plots. Also, no significant differences were found in liana density, dead tree or damage for margin and interior plots. The peculiar topographic conditions associated with the matrix habitat and shapes of the island seem to extend edge effects to the islands' centers independently of the island size, giving the interior similar physical microclimatic conditions as at the edges. We propose a protocol for assessing the ecological impacts of edge effects in fragments of natural habitat surrounded by induced (artificial) edges. The protocol involves three steps: (1) identification of focal taxa of particular conservation or management interest, (2) measurement of an "edge function" that describes the response of these taxa to induced edges, and (3) use of a "Core-Area Model" to extrapolate edge function parameters to existing or novel situations.

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In this study we present a new record of a plant-animal interaction: the mutualistic relationship between the specialist plant-ant Myrcidris epicharis Ward, 1990 (Pseudomyrmecinae) and its myrmecophyte host Myrcia madida McVaugh (Myrtaceae). We observed more than 50 individuals of M. madida occupied by M. epicharis in islands and margins of the Juruena River, in Cotriguaçu, Mato Grosso, Brazil (Meridional Amazon). We discuss a possible distribution of this symbiotic interaction throughout all the riparian forest of the Amazon River basin and its consequence to coevolution of the system.

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Observational and experimental studies have shown that increased concealment of bird nests reduces nest predation rates. The objective of the present study was to evaluate differences in predation rates between two experimental manipulations of artificial ground nests (i.e., clearing an area around the artificial nest or leaving it as natural as possible), and test whether environmental variables also affected nest predation in an undisturbed area of Amazonian forest in eastern Brazil. A generalized linear model was used to examine the influence of five variables (manipulation type, perpendicular distance from the main trail, total basal area of trees surrounding the nest site, understorey density, and liana quantity) on nest predation rates. Model results, showed that manipulation type was the only variable that significantly affected nest predation rates. Thus, to avoid systematic biases, the influence of nest site manipulation must be taken into consideration when conducting experiments with artificial nests.

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Mapania belongs to Mapanioideae, a quite controversial subfamily in Cyperaceae due to the existence of unusual characters in both reproductive and vegetative organs. The genus is represented by seven species in Northern Brazil but taxonomic valuable information related to the leaf organs is still unknown. The present study aimed the anatomical description of the leaf organs (either basal leaves or cataphylls and involucral bracts) of three representative Brazilian species of Mapania. Samples of cataphylls, basal leaves and involucral bracts were sectioned and stained for observations under light microscopy. The involucral bracts provide the most elucidative characters (ten) to distinguish the three species The basal leaves provides six distinguishing characters and are useful to M. macrophylla and M. pycnostachya, as they are absent in M. sylvatica. Mesophyll arrangement in the involucral bracts supports the circumscription of M. macrophylla and M. pycnostachya in M. sect. Pycnocephala and of M. sylvatica in M. sect. Mapania. Some features as thin-walled epidermal cells, stomata level and aerenchyma were considered to be adaptive to the humid environment in which the species occur. The translucent cells are here considered as aerenchyma precursors and a supportive function is assumed for the bulliform cells on the basal leaves and involucral bracts. No silica bodies were found which confirm it as a diagnostic character of Mapania among Hypolytreae genera.

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Pressures on the Brazilian Amazon forest have been accentuated by agricultural activities practiced by families encouraged to settle in this region in the 1970s by the colonization program of the government. The aims of this study were to analyze the temporal and spatial evolution of land cover and land use (LCLU) in the lower Tapajós region, in the state of Pará. We contrast 11 watersheds that are generally representative of the colonization dynamics in the region. For this purpose, Landsat satellite images from three different years, 1986, 2001, and 2009, were analyzed with Geographic Information Systems. Individual images were subject to an unsupervised classification using the Maximum Likelihood Classification algorithm available on GRASS. The classes retained for the representation of LCLU in this study were: (1) slightly altered old-growth forest, (2) succession forest, (3) crop land and pasture, and (4) bare soil. The analysis and observation of general trends in eleven watersheds shows that LCLU is changing very rapidly. The average deforestation of old-growth forest in all the watersheds was estimated at more than 30% for the period of 1986 to 2009. The local-scale analysis of watersheds reveals the complexity of LCLU, notably in relation to large changes in the temporal and spatial evolution of watersheds. Proximity to the sprawling city of Itaituba is related to the highest rate of deforestation in two watersheds. The opening of roads such as the Transamazonian highway is associated to the second highest rate of deforestation in three watersheds.

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This study compares the physicochemical characteristics of six species from Brazilian Malvaceae family with natural fibers of recognized applicability in the industry. The objective of the present study is present the physicochemical characterization of six Brazilian vegetal fibers: Sida rhombifolia L.; Sida carpinifolia L. f.; Sidastrum paniculatum (L.) Fryxell; Sida cordifolia L.; Malvastrum coromandelianum (L.) Gurck; Wissadula subpeltata (Kuntze) R.E.Fries. Respectively the two first species are from Brazilian Atlantic Forest biome and the four remaining from Brazilian Cerrado biome, despite of present in other regions of the plane

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The sterile castes of Ibitermes inflatus sp. nov. from Rio Tinto, State of Paraíba, Brazil are described and illustrated. This is the first record of a species of Ibitermes from the Brazilian northeast and from the Atlantic Forest biome. The absence of ridges in the molar plate of the left mandible and the presence of granules of sand and silt mixed with organic matter in advanced stage of decomposition in the digestive tube of workers suggest that the species is a typical humus feeding termite.

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I report on the occurrence of 16 species of birds in Rio Grande do Sul, southern Brazil, of which seven are new for the state - Accipiter superciliosus (Linnaeus, 1766), Brotogeris tirica (Gmelin, 1788), Hemitriccus margaritaceiventer (d'Orbigny & Lafresnaye, 1837), Phyllomyias griseocapilla Sclater, 1862, Saltator coerulescens Vieillot, 1817, Orthogonys chloricterus (Vieillot, 1819), and Sporophila lineola (Linnaeus, 1758) - and seven were previously known from unsubstantiated or poorly documented records - Ixobrychus exilis (Gmelin, 1789), Brotogeris chiriri (Vieillot, 1818), Coccyzus euleri Cabanis, 1873, Pulsatrix koeniswaldiana (Bertoni & Bertoni, 1901), Psilorhamphus guttatus (Ménétriès, 1835), Serpophaga griseicapilla Straneck, 2007, and Hemithraupis ruficapilla (Vieillot, 1818). Descriptive and natural history notes are presented for some of these species. The records of B. tirica, P. guttatus, P. griseocapilla, Myiozetetes similis (Spix, 1825), O. chloricterus, H. ruficapilla, and S. lineola represent significant southward range extensions of up to 300 km. Also, a new confirmed record of Myiarchus ferox (Statius Muller, 1776) is divulged. Finally, I argue that the Atlantic forests of north-eastern Rio Grande do Sul should be included in the Serra do Mar area of endemism (sensu SILVA et al., 2004) because of the presence of Orthogonys chloricterus, and comment on the possible range expansion of Myiozetetes similis, Sporophila lineola and other primarily tropical species in southern Brazil.

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The semi terrestrial crabs are important elements of the fauna of coastal regions. The aim of this study was to analyze the population structure of Armases angustipes (Dana, 1852) at estuaries of the Ariquindá River, considered a non impacted area, and Mamucabas River, considered a few impacted area, on the south coast of state of Pernambuco, Brazil. The species occurred in all months of the year. The number of individuals per month varied, being higher in the months of transition between the seasons. This is probably due to significant seasonal variations of air and burrow temperature and burrow salinity. There was no sexual dimorphism in size of A. angustipes in the mangrove of Ariquindá River, but males were larger than females in the mangrove of Mamucabas River. In both estuaries, the sex ratio did not differ from Mendelian proportion, but showed a deviation for females. The analysis of temporal variation in sex ratio showed significant differences in some months of the year. These variations are due to cyclical events that act distinctly on each sex. In both estuaries, size classes of carapace width were equally represented by both sexes. The ovigerous females of A. angustipes occurred only in some months of the year, especially in summer, in both estuaries. Probably the high phytoplankton productivity observed in summer favors the reproductive activity, since these algae serve as food for the larvae. Specimens of the population of Rio Ariquindá are largest and wider than those of Mamucabas River. This fact, associated with the low abundance of crabs and the lower frequency of ovigerous females observed in Mamucabas River, is an indication that this population may be influenced by the environmental impacts that this estuary has received.

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We assessed the species composition and abundance of medium and large-sized mammals in an urban forest fragment in the Brazilian Amazon, and recorded the preference of some species for particular phytophysiognomies. We placed nine transects with 20 sand plots each in three phytophysiognomies: open rainforest with a dominance of bamboos (OFB), open rainforest with palm trees (OFP), and dense rainforest (DF). We calculated species abundance as the number of records/plot.day, in a total of 2,700 plots.day. We recorded twelve mammal species; Sylvilagus brasiliensis (Linnaeus, 1758) and Dasyprocta fuliginosa (Wagler, 1831) were the most abundant. The results differed among phytophysiognomies: DF presented the highest mammal diversity, whereas the species composition of OFP was less similar than that of other phytophysiognomies. Rodents showed higher preference for OFP and Sylvilagus brasiliensis was more abundant in OFB. The study area showed high species richness, with the occurrence of mesopredators, but there was a predominance of common species adaptable to disturbed environments, which reflects the severe isolation degree of the forest fragment and the hunting pressure that is still present.