997 resultados para Brazilian Amazon rainforest


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Deforestation in Brazilian Amazonia accounts for a disproportionate global scale fraction of both carbon emissions from biomass burning and biodiversity erosion through habitat loss. Here we use field- and remote-sensing data to examine the effects of private landholding size on the amount and type of forest cover retained within economically active rural properties in an aging southern Amazonian deforestation frontier. Data on both upland and riparian forest cover from a survey of 300 rural properties indicated that 49.4% (SD = 29.0%) of the total forest cover was maintained as of 2007. and that property size is a key regional-scale determinant of patterns of deforestation and land-use change. Small properties (<= 150 ha) retained a lower proportion of forest (20.7%, SD = 17.6) than did large properties (>150 ha; 55.6%, SD = 27.2). Generalized linear models showed that property size had a positive effect on remaining areas of both upland and total forest cover. Using a Landsat time-series, the age of first clear-cutting that could be mapped within the boundaries of each property had a negative effect on the proportion of upland, riparian, and total forest cover retained. Based on these data, we show contrasts in land-use strategies between smallholders and largeholders, as well as differences in compliance with legal requirements in relation to minimum forest cover set-asides within private landholdings. This suggests that property size structure must be explicitly considered in landscape-scale conservation planning initiatives guiding agro-pastoral frontier expansion into remaining areas of tropical forest. (C) 2010 Elsevier Ltd. All rights reserved.

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The use of scat surveys to obtain DNA has been well documented in temperate areas, where DNA preservation may be more effective than in tropical forests. Samples obtained in the tropics are often exposed to high humidity, warm temperatures, frequent rain and intense sunlight, all of which can rapidly degrade DNA. Despite these potential problems, we demonstrate successful mtDNA amplification and sequencing for faeces of carnivores collected in tropical conditions and quantify how sample condition and environmental variables influence the success of PCR amplification and species identification. Additionally, the feasibility of genotyping nuclear microsatellites from jaguar (Panthera onca) faeces was investigated. From October 2007 to December 2008, 93 faecal samples were collected in the southern Brazilian Amazon. A total of eight carnivore species was successfully identified from 71% of all samples obtained. Information theoretic analysis revealed that the number of PCR attempts before a successful sequence was an important negative predictor across all three responses (success of species identification, success of species identification from the first sequence and PCR amplification success), whereas the relative importance of the other three predictors (sample condition, season and distance from forest edge) varied between the three responses. Nuclear microsatellite amplification from jaguar faeces had lower success rates (15-44%) compared with those of the mtDNA marker. Our results show that DNA obtained from faecal samples works efficiently for carnivore species identification in the Amazon forest and also shows potential for nuclear DNA analysis, thus providing a valuable tool for genetic, ecological and conservation studies.

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Roads facilitate access by deforestation agents, being relevant in studies approaching conservationist matters in rainforests. It is important to understand the relationship between road distribution, relief, land use, and forest coverage in order to evaluate where forests are more vulnerable. This study aimed at: 1) understanding the relationship between relief and density and road connectivity in three moments in time; and 2) evaluating the relationship between distance from roads and forest coverage, farmlands and rural and urban facilities in a fragmented Atlantic Forest landscape in three moments in time. Maps of roads, altitude, and land use and coverage were used. Chi-square tests showed that: 1) density and road connectivity did not present significant relationship with the relief; and 2) forest areas occupy areas distant from the roads, while farmlands and rural and urban facilities occupy areas nearer the roads. Roads and land use, regardless of relief, influence forest coverage distribution. Thus, we suggest that roads are taken into account in conservationist strategies and environmental planning.

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Objectives: The goal of this study was to understand the relationship between economic change (wage labor, retirement, and the Bolsa Familia program) and dietary patterns in the rural Amazon and to determine the extent to which these changes followed the pattern of the nutrition transition. Methods: The study was longitudinal. The weighed-inventory method and economic interviews were used to collect data on dietary intake and household economics in a sample of 30 and 52 women in 2002 and 2009, respectively. Twenty of the women participated in both years and make-up the longitudinal sub-sample. Comparative statistics were used to identify changes in dietary patterns over time and multiple linear regressions were used to explore the relationship between economics, subsistence strategies, and diet. Results: There was a significant decline in kcal (P < 0.01) and carbohydrate (P < 0.01) but no change in protein intake over time in both the larger and smaller, longitudinal subsample. The percent of energy, carbohydrate, protein, and fat purchased increased in the larger and longitudinal samples (P <= 0.02) and there was an increase in refined carbohydrate and processed, fatty-meat consumption over time. The abandonment of manioc gardens was associated with increased dependence on purchased food (P = 0.03) while receipt of the Bolsa Familia was associated with increased protein intake and adequacy (P = 0.02). Conclusions: The dietary changes observed are only in partial agreement with predictions of the nutrition transition literature. The relationship between the economic and diet changes was shaped by the local context which should be considered when implementing CCT programs, like the Bolsa Familia. Am. J. Hum. Biol. 23:458-469, 2011. (C) 2011 Wiley-Liss, Inc.

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We describe Kochiana new genus to accommodate a small Brazilian theraphosine species described originally as Mygale brunnipes by Koch (1842), resulting in Kochiana brunnipes new combination. Recently, specimens were rediscovered in northeastern Brazilian Atlantic rainforest. A preliminary cladistic analysis using equal weights parsimony and implied weights, was carried out to examine its phylogenetic placement. Kochiana new genus was monophyletic in all trees regardless of weighting scheme or concavity used. There is preliminary evidence for Kochiana new genus monophyly and weak evidence for its placement as sister group of Plesiopelma. Kochiana new genus can be characterized by the presence of a hornshaped spermatheca in females and males with a palpal bulb having prolateral accessory keels and a well developed medial crest on the embolus apex.

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One of the most significant challenges confronting orchid researchers is the lack of specific molecular markers, mainly for species in the Neotropics. Here we report the first set of specific chloroplast microsatellite primers (cpSSR) developed for Neotropical orchids. In total, nine polymorphic cpSSR loci were isolated and characterized in four species occurring in the Brazilian Atlantic Rainforest: Epidendrum cinnabarinum, E. denticulatum, E. fulgens and E. puniceoluteum. Levels of intraspecific polymorphism were characterized using two populations for each species, with 13-20 individuals each. Allele numbers varied from two to three per locus, while the number of haplotypes ranged from three to six per species. Extensive differentiation among the taxa was detected. All markers were successfully cross-amplified in eight other different genera. These cpSSRs markers will enable novel insights into the evolution of this important Neotropical genus.

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Trypanosoma cruzi and Trypanosoma rangeli are human-infective blood parasites, largely restricted to Central and South America. They also infect a wide range of wild and domestic mammals and are transmitted by a numerous species of triatomine bugs. There are significant overlaps in the host and geographical ranges of both species. The two species consist of a number of distinct phylogenetic lineages. A range of PCR-based techniques have been developed to differentiate between these species and to assign their isolates into lineages. However, the existence of at least six and five lineages within T. cruzi and T. rangeli, respectively, makes identification of the full range of isolates difficult and time consuming. Here we have applied fluorescent fragment length barcoding (FFLB) to the problem of identifying and genotyping T. cruzi, T. rangeli and other South American trypanosomes. This technique discriminates species on the basis of length polymorphism of regions of the rDNA locus. FFLB was able to differentiate many trypanosome species known from South American mammals: T. cruzi cruzi. T. cruzi marinkellei, T. dionisii-like, T. evansi, T. lewisi, T. rangeli, T. theileri and T. vivax. Furthermore, all five T. rangeli lineages and many T. cruzi lineages could be identified, except the hybrid lineages TcV and TcVI that could not be distinguished from lineages III and II respectively. This method also allowed identification of mixed infections of T. cruzi and T. rangeli lineages in naturally infected triatomine bugs. The ability of FFLB to genotype multiple lineages of T. cruzi and T. rangeli together with other trypanosome species, using the same primer sets is an advantage over other currently available techniques. Overall, these results demonstrate that FFLB is a useful method for species diagnosis, genotyping and understanding the epidemiology of American trypanosomes. (C) 2010 Elsevier B.V. All rights reserved.

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Immune evasion by Plasmodium falciparum is favored by extensive allelic diversity of surface antigens. Some of them, most notably the vaccine-candidate merozoite surface protein (MSP)-1, exhibit a poorly understood pattern of allelic dimorphism, in which all observed alleles group into two highly diverged allelic families with few or no inter-family recombinants. Here we describe contrasting levels and patterns of sequence diversity in genes encoding three MSP-1-associated surface antigens of P. falciparum, ranging from an ancient allelic dimorphism in the Msp-6 gene to a near lack of allelic divergence in Msp-9 to a more classical multi-allele polymorphism in Msp-7 Other members of the Msp-7 gene family exhibit very little polymorphism in non-repetitive regions. A comparison of P. falciparum Msp-6 sequences to an orthologous sequence from P. reichenowi provided evidence for distinct evolutionary histories of the 5` and 3` segments of the dimorphic region in PfMsp-6, consistent with one dimorphic lineage having arisen from recombination between now-extinct ancestral alleles. In addition. we uncovered two surprising patterns of evolution in repetitive sequence. Firsts in Msp-6, large deletions are associated with (nearly) identical sequence motifs at their borders. Second, a comparison of PfMsp-9 with the P. reichenowi ortholog indicated retention of a significant inter-unit diversity within an 18-base pair repeat within the coding region of P. falciparum, but homogenization in P. reichenowi. (C) 2009 Elsevier B.V. All rights reserved.

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We characterized 15 Trypanosoma cruzi isolates from bats captured in the Amazon, Central and Southeast Brazilian regions. Phylogenetic relationships among T. cruzi lineages using SSU rDNA, cytochrome b, and Histone H2B genes positioned all Amazonian isolates into T. cruzi I (TCI). However, bat isolates from the other regions, which had been genotyped as T. cruzi II (TC II) by the traditional genotyping method based on mini-exon gene employed in this study, Were not nested within any of the previously defined TCII sublineages, constituting a new genotype designated as TCbat. Phylogenetic analyses demonstrated that TCbat indeed belongs to T. cruzi and not to other closely related bat trypanosomes of the subgenus Schizotrypanum, and that although separated by large genetic distances TO-tat is closest to lineage TCI. A genotyping method targeting ITS1 rDNA distinguished TCbat from established T. cruzi lineages, and from other Schizotrypanum species. In experimentally infected mice, TCbat lacked virulence and yielded loss parasitaemias. Isolates of TCbat presented distinctive morphological features and behaviour in triatomines. To date, TCbat genotype wall found only in bats from anthropic environments of Central and Southeast Brazil. Our findings indicate that the complexity of T. cruzi is larger than currently known, and confirmed bats as important reservoirs and potential source of T. cruzi infections to humans.

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The Plasmodium falciparum var gene family encodes large variant antigens, which are important virulence factors, and also targets of the humoral host response. The frequently observed mild outcomes of falciparum malaria in many places of the Amazon area prompted us to ask whether a globally restricted variant (var) gene repertoire is present in currently circulating and older isolates of this area. By exhaustive analysis of var gene tags from 89 isolates and clones taken during many years from all over the Brazilian Amazon, we estimate that there are probably no more than 350-430 distinct sequence types, less than for any similar sized area studied so far. Detailed analysis of the var tags from genetically distinct clones obtained from single isolates revealed restricted and redundant repertoires suggesting either a low incidence of infective bites or restricted variant gene diversity in inoculated parasites. Additionally, we found a structuring of var gene repertoires observed as a higher pairwise typing sharing in isolates from the same microregion compared to isolates from different regions. Fine analysis of translated var tags revealed that certain Distinct Sequence Identifiers (DSIDs) were differently represented in Brazilian/South American isolates when compared to datasets from other continents. By global alignment of worldwide var DBL alpha sequences and sorting in groups with more than 76% identity, 125 clusters were formed and more than half of all genes were found in nine clusters with 50 or more sequences. While Brazilian/South American sequences were represented only in 64 groups, African sequences were found in the majority of clusters. DSID type 1 related sequences accumulated almost completely in one single cluster, indicating that limited recombination occurs in these specific var gene types. These data demonstrate the so far highest pairwise type sharing values for the var gene family in isolates from all over an entire subcontinent. The apparent lack of specific sequences types suggests that the P. falciparum transmission dynamics in the whole Amazon are probably different from any other endemic region studied and possibly interfere with the parasite`s ability to efficiently diversify its variant gene repertoires. (C) 2010 Elsevier B.V. All rights reserved.

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The Duffy binding protein of Plasmodium vivax (DBP) is a critical adhesion ligand that participates in merozoite invasion of human Duffy-positive erythrocytes. A small outbreak of P. vivax malaria, in a village located in a non-malarious area of Brazil, offered us an opportunity to investigate the DBP immune responses among individuals who had their first and brief exposure to malaria. Thirty-three individuals participated in the five cross-sectional surveys, 15 with confirmed P. vivax infection while residing in the outbreak area (cases) and 18 who had not experienced malaria (non-cases). In the present study, we found that only 20% (three of 15) of the individuals who experienced their first P. vivax infection developed an antibody response to DBP; a secondary boosting can be achieved with a recurrent P. vivax infection. DNA sequences from primary/recurrent P. vivax samples identified a single dbp allele among the samples from the outbreak area. To investigate inhibitory antibodies to the ligand domain of the DBP (cysteine-rich region II, DBP(II)), we performed in vitro assays with mammalian cells expressing DBP(II) sequences which were homologous or not to those from the outbreak isolate. In non-immune individuals, the results of a 12-month follow-up period provided evidence that naturally acquired inhibitory antibodies to DBP(II) are short-lived and biased towards a specific allele.

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Este estudo foi desenvolvido com o fim de analisar as perspectivas para o empreendedorismo sustentável na Amazônia, a partir de uma revisão bibliográfica sobre o tema. Para tanto, foram analisadas as ações, públicas e privadas, que podem ser adotadas para incentivar tal empreendedorismo. Ademais, foi feito um estudo da Agenda 21, Protocolo de Quioto e núcleos de empreendedorismo sustentável. Com base nessas fontes de consulta pode-se concluir que intervenções endógenas não irão promover este desenvolvimento, pois é fundamental que os setores públicos e privados sejam agentes de ação para que o empreendedorismo sustentável seja fomentado na Amazônia. É preciso criar condições para se desenvolver o espírito empreendedor do “povo da floresta” no intuito de que eles sejam cidadãos, no mais amplo sentido que esta palavra possa ter. Isto é, que as comunidades que vivem na Floresta possuam emprego e renda, e que esta fonte econômica venha de forma sustentável com origem na floresta, de modo a mostrar às comunidades que a floresta é muito mais valiosa viva do que morta. A preservação da Floresta Amazônica pelos que lá habitam, certamente será garantida, já que não há ninguém melhor para protegê-la do que seus próprios núcleos vivos.

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The extent of the Brazilian Atlantic rainforest, a global biodiversity hotspot, has been reduced to less than 7% of its original range. Yet, it contains one of the richest butterfly fauna in the world. Butterflies are commonly used as environmental indicators, mostly because of their strict association with host plants, microclimate and resource availability. This research describes diversity, composition and species richness of frugivorous butterflies in a forest fragment in the Brazilian Northeast. It compares communities in different physiognomies and seasons. The climate in the study area is classified as tropical rainy, with two well defined seasons. Butterfly captures were made with 60 Van Someren-Rydon traps, randomly located within six different habitat units (10 traps per unit) that varied from very open (e.g. coconut plantation) to forest interior. Sampling was made between January and December 2008, for five days each month. I captured 12090 individuals from 32 species. The most abundant species were Taygetis laches, Opsiphanes invirae and Hamadryas februa, which accounted for 70% of all captures. Similarity analysis identified two main groups, one of species associated with open or disturbed areas and a second by species associated with shaded areas. There was a strong seasonal component in species composition, with less species and lower abundance in the dry season and more species and higher abundance in the rainy season. K-means analysis indicates that choice of habitat units overestimated faunal perceptions, suggesting less distinct units. The species Taygetis virgilia, Hamadryas chloe, Callicore pygas e Morpho achilles were associated with less disturbed habitats, while Yphthimoides sp, Historis odius, H. acheronta, Hamadryas feronia e Siderone marthesia likey indicate open or disturbed habitats. This research brings important information for conservation of frugivorous butterflies, and will serve as baseline for future projects in environmental monitoring

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The present study discusses the geographical distribution and the context on the occupation of mangrove swamp areas by capuchin monkeys. In addition, we assess how the dispersion to the mangrove allowed the exploration of different food items, permitting the development of predation by ambush and the use of cracking tools. From 2004 to 2008 we surveyed the main estuaries of Brazilian Amazon coast, from northeastern state of Pará to the eastern boundary of the state of Maranhão, and recorded the presence of two species of capuchin monkeys in the mangrove forest areas. Cebus apella has been widely distributed in the mangrove at the estuaries examined (excluding C. libidinosus areas). Its presence is often related to Amazon forest remnants in the neighbourhood of the mangrove swamps and thus it is possible that some groups live in both kinds of habitats. However, we recorded some populations restricted only to mangrove swamp surrounded by open areas. On the other hand, Cebus libidinosus had a distribution more restricted and isolated in mangroves. Its pattern of habitat use is consistent with geographic distribution in mangrove patches. It seems that the possible contact zone previously proposed in the literature for that two species has no evident barriers in the mangrove. Furthermore, we record cracking sites and systematic observations on the tool use, carnivory and predation by ambush in Cebus libidinosus from 2006 to 2008. Cebus libidinosus is the only Neotropical primate species in which the tool use has been systematically recorded in nature. However all previous studies had been obtained is open areas (Cerrado and Caatinga). Thus, the present study is first one to report that behaviour in forested habitats in which the tool use to cracking by capuchin monkeys is associated with the consumption of meat. In the Caatinga and Cerrado, food shortages and terrestriality has been proposed by different authors to explain the evolution of tool use in primates. Here, we analyzed the relative contribution of these two variables as selective pressures for the tool use by capuchin monkeys in the mangrove forests, an ecological scenario in which food resources is available around the year and terrestriality is limited by structural habitat features, as the presence of stilt roots and muddy soil