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Sample records for roraima amazonia brazil

  1. Simulating deforestation and carbon loss in Amazonia: impacts in Brazil's Roraima state from reconstructing Highway BR-319 (Manaus-Porto Velho).

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    Barni, Paulo Eduardo; Fearnside, Philip Martin; Graça, Paulo Maurício Lima de Alencastro

    2015-02-01

    Reconstruction of Highway BR-319 (Manaus-Porto Velho) would allow for access from the "arc of deforestation" in the southern part of Brazil's Amazon region to vast blocks of forests in central and northern Amazonia. Building roads is known to be a major driver of deforestation, allowing entry of squatters, and other actors. Rather than deforestation along the highway route, here we consider the road's potential for stimulating deforestation in a separate location, approximately 550 km north of BR-319's endpoint in Manaus. Reconstructing BR-319 has great potential impact to start a new wave of migration to this remote region. The southern portion of the state of Roraima, the focus of our study, is already connected to Manaus by Highway BR-174. We modeled deforestation in southern Roraima and simulated carbon emissions between 2007 and 2030 under four scenarios. Simulations used the AGROECO model in DINAMICA-EGO © software. Two scenarios were considered with reconstruction of BR-319 and two without this road connection. For each of the two possibilities regarding BR-319, simulations were developed for (1) a "conservation" (CONSERV) scenario that assumes the creation of a series of protected areas, and (2) a "business-as-usual" (BAU) scenario that assumes no additional protected areas. Results show that by 2030, with BR-319 rebuilt, deforestation carbon emissions would increase between 19% (CONSERV) and 42% (BAU) over and above those corresponding to no-road scenarios.

  2. Malaria and antimalarial plants in Roraima, Brazil.

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    Milliken, W

    1997-01-01

    One of the numerous problems created by the gold rush which took place in northern Brazil (Roraima State) at the end of the 1980s was a severe epidemic of malaria amongst the indigenous peoples of the region. Worst hit were the Yanomami Indians, who had lived in almost total isolation prior to this event. The problem has been exacerbated by the development of chloroquine-resistant strains of Plasmodium falciparum. In an effort to identify viable alternatives to dependence on western medicine for malaria treatment, a survey was carried out on the local plant species (wild and cultivated) used for this purpose in Roraima. Fieldwork was carried out amongst seven indigenous peoples, as well as with the non-indigenous settlers. Over 90 species were collected, many of which have been cited as used for treatment of malaria and fevers elsewhere. Knowledge of antimalarial plants was found to vary greatly between the communities, and in some cases there was evidence of recent experimentation. Initial screening of plant extracts has shown a high incidence of significant antimalarial activity amongst the species collected.

  3. Orchid’s diversity at Tepequém’s Tepuy, Roraima, Brazil

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    Sanna Rocha Nobrega

    2016-10-01

    Full Text Available The Orchidaceae family is one of the largest among the angiosperm, with more than 27000 species, 2,500 is endemic to Brazil, 871 species are found in the Brazilian Amazon. In the far north of Brazil, in the state of Roraima, is located the Tepequém Mountains, a Tepuy – mountain top with table shape – with relictual vegetation due to prolonged isolation. Historically, Tepequém was a site of diamond exploration, which caused changes in the landscape. However, with mining decay, ecotourism became the main economic activity. About 68% of Roraima’s territory is composed of conservation areas and indigenous lands, and the Tepequém Mountain is the only Tepuy found outside the protected areas. Thus, this study aims to describe the orchid flora found at Tepequém’s Tepuy, an area of ecological and economic importance for Roraima’s ecotourism. The survey was carried out through expeditions between the years of 2013-2015. The species were photographed, harvested and taken to Embrapa Roraima for identification, exsiccate confection and/or cultivation. The exsiccatae were deposited at Roraima’s Integrated Museum (Museu Integrado de Roraima – MIRR and the Federal University of Roraima (Universidade Federal de Roraima – UFRR. Any orchid species deposited by other collectors was also considered. Thus, 20 genera and 34 species were registered at Tepequém. The genera with largest representation were the Epidendrum (7 spp., Scaphyglottis (4 spp. and Habenaria (3 spp., with 70% of the other genera presenting one species only. 10% of Roraima’s orchid’s diversity is found at Tepequém. The diversity of habitats – forest, campina and savannah – found at Tepequém’s Tepuy allows the Orchidaceae species diversity and the unique flora with low similarities to other floristic surveys.

  4. First Occurrence of Ceratitis capitata (Wied. in the State of Roraima, Brazil = Primeira ocorrência de Ceratitis capitata (Wied. no Estado de Roraima, Brasil

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    Luciana Baú Trassato

    2017-03-01

    Full Text Available Due to its cosmopolitan and invasive characteristics, the Mediterranean fruit fly, Ceratitis capitata (Wied., is considered to be the most harmful tephritide to global fruit farming, causing greater losses in production than any other species of the same family. In Brazil, it was first detected in 1901 in the state of São Paulo, and was present in 22 of the 27 federated states by 2014. Because of its economic importance and the continual entry of hosts into the state, the hypothesis of this work was that the Mediterranean fruit fly [Ceratitis capitata (Wied.] is already present in the State of Roraima. Weekly collections of potential host fruits were carried out in October 2014 in urban areas of the city of Boa Vista, Roraima. The collected fruit was taken to the Entomology Laboratory of the Federal University of Roraima, where they were weighed, counted and packed under controlled conditions of temperature and humidity in order to obtain pupae. After emergence, the flies were fed on water with 25% honey for two days, fixed in 70% alcohol and sent for identification to the Department of Entomology Research of the Amazon National Research Institute (INPA in Manaus. In this way, Specimens of Ceratitis capitata (Wied. (Diptera: Thephritidae were detected in fruit of the guava (Psidium guajava L., validating the hypothesis that the pest is already present in Roraima. The first record of the occurrence of Ceratitis capitata (Wied. in the state of Roraima is therefore reported here. = A mosca-do-mediterrâneo, Ceratitis capitata (Wied., por apresentar características cosmopolita e invasora, é considerada o tefritideo mais nocivo à fruticultura mundial, causando perdas produtivas superiores a qualquer outra espécie da sua família. No Brasil, foi primeiramente detectada em 1901 no estado de São Paulo, e estava presente em 22 das 27 unidades federativas até o ano de 2014. Em razão da sua importância econômica e da constante entrada de

  5. Anastrepha species (Diptera: Tephritidae, their host plants and parasitoids (Hymenoptera in the state of Roraima, Brazil: state of the art

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    Alberto Luiz Marsaro Júnior

    2017-02-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2017v30n1p13 The aim of this review was to update the available information on Anastrepha species in the state of Roraima, Brazil, with emphasis on distribution, host plants and parasitoids. In total, 25 species of Anastrepha and 27 host plant species have been recorded to date in Roraima. Anastrepha striata and A. obliqua are widely distributed in the state. Anastrepha obliqua is the most polyphagous species, where it is associated with 13 hosts. Six species of parasitoids of Anastrepha have been reported in Roraima. Of these, Doryctobracon areolatus is the most abundant and has been associated with the largest number of Anastrepha species.

  6. Omega-6/Omega-3 and PUFA/SFA in Colossoma macropomum Grown in Roraima, Brazil

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    Antonio Alves Melho Filho

    2013-05-01

    Full Text Available In this study was evaluated the fatty acids composition of tambaqui (Colossoma macropomum fillet, fish species cultivated in Roraima State, Brazil. For the extraction of tambaqui oil was used Sohxlet device and then it was methylated. The oil  was identified using a gas chromatograph and were identified 24 acids and these were divided into characteristic groups such as: saturated fatty acids (SFA, monounsaturated fatty acids (MUFA, polyunsaturated fatty acids (PUFA and series fatty acids omega-6 and omega-3. The ratios obtained were PUFA/SFA and omega-6/omega-3. The results of chromatographic analysis were subjected to tests by variance ANOVA and multiple comparisons of Tukey at 5%. The ratios omega-6/omega-3 and PUFA/SFA showed values ​​of 8.58 and 0.75 respectively.

  7. Notas sobre a composição arbóreo-arbustiva de uma fisionomia das savanas de Roraima, Amazônia Brasileira Notes on the woody composition of a vegetation physionomy of the Roraima's savannas, Brazilian Amazonia

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    Reinaldo Imbrozio Barbosa

    2005-06-01

    Full Text Available Foi realizado um inventário florístico das espécies arbóreo-arbustivas presentes em uma das unidades de vegetação que compõem a paisagem de savanas do Estado de Roraima, extremo norte da Amazônia brasileira. Esta unidade é caracterizada por ser densamente colonizada por ninhos do cupim Cornitermes ovatus Emerson. Foram observadas 29 espécies (15 famílias botânicas em três localidades utilizadas para a amostragem. O total de espécies, por localidade, variou de 12 a 20. As espécies mais abundantes foram Byrsonima verbascifolia (L. DC. e Mimosa microcephala Humb. & Bonpl. ex Willd. (subarbustivas, Byrsonima cf. intermedia A. Juss. e Randia formosa (Jack. K. Schum. (arbustivas e, Byrsonima crassifolia (L. H.B.K. e Curatella americana L. (arbóreas. Oito espécies são comuns às três localidades. A diversidade medida pelo Índice de Shannon (H' foi baixa para todos os locais amostrados (A floristic inventory of woody species was carried out in one of the vegetation units that compose the savannas landscape of the Roraima State, northernmost of Brazilian Amazonia. This unit is characterized by dense colonization of nests of termites Cornitermes ovatus Emerson. Twenty nine woody species were observed (15 botany families in three localities used for sampling. The total of species varied from 12 to 20 by locality. The most abundant species were Byrsonima verbascifolia (L. DC. and Mimosa microcephala Humb. & Bonpl. ex Willd. (dwarf shrubs, Byrsonima cf. intermedia A. Juss. and Randia formosa (Jack. K. Schum. (shrubby and, Byrsonima crassifolia (L. H.B.K. and Curatella americana L. (arboreal. Eight species are common to all localities. Diversity measured by the Index of Shannon (H' was low for all the areas sampled (<0.90 indicating high specimens concentration in few species. The Index of Sørensen indicated similarities (± 0.60 among studied areas, suggesting a group of landscapes with common plant diversity, representing a same

  8. Study of the radiological procedures used in odontologic clinics of Boa Vista, Roraima, Brazil

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    Costa, Jaberson Luiz Leitao

    2002-04-01

    The purpose of this study was to evaluate the radiological procedures used at the odontologic clinics of Boa Vista, Roraima-Brazil. The following parameters were recorded: field diameter, half value layer, total filtration, discrepancy between the preset and the applied kilovoltage and exposure time. Dose to the patient's skin from radiography of the upper molar tooth was also estimated. The results showed that 78% of the inspected units had field diameters larger than 6,0 cm, which is outside the limits recommended by the Brazilian Health Ministry. The results also showed that 14% of the equipment presented a discrepancy of more than 10% between preset and applied kilovoltage. On the other hand, the discrepancy between preset and applied exposure time is higher than 10% in 70% of the tested units. The total filtration of 77% units is lower than 1,5 mm of Al, a value recommended by the Brazilian Health Ministry for equipment that operates in the range of 50 kV to 70 kV. The survey also indicates that for 35% of the units the entrance dose in high than 3,5 mGy that is the reference value established by the Brazilian Health Ministry for dental radiography with film type. It was observed that the majority of the clinics use neither aprons nor collars for patients and that films are processed manually, without controlling temperature or processing time. Based on the results obtained it is strongly recommended that a quality control program be implemented in dental radiological clinics in Boa Vista, Roraima. (author)

  9. Climatic conditions for grapevine cultivation in Boa Vista, Roraima, Brazil = Aptidão climática para o cultivo da videira em Boa Vista, Roraima

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    Marco Antônio Fonseca Conceição

    2014-12-01

    Full Text Available Grapevine plants have been grown in different tropical regions of Brazil. In the state of Roraima, this culture was introduced commercially in 2005 in Boa Vista. Unlike temperate regions, tropical regions present thermal conditions for grape production throughout the year. To evaluate the climatic characteristics on different periods of the year, it can be used different indices. The objective of this study was to characterize climate suitability of Boa Vista, Roraima, Brazil, for grapevine cultivation at different months of the year. For climate classification it was used the Geoviticulture Multicriteria Climatic Classification System (CCM, which is composed by three indices: Heliothermal (IH, Cool Night (IF, and Drought (IS. It was also used the Zuluaga Index (IZ, to assess the risk of incidence of fungal diseases on the vine, especially in relation to the incidence of downy mildew (Plasmopara viticola, one of the main grapevine diseases in humid regions. Based on the evaluated indices, it was found that the most favorable period for grape production goes from October to March because of the lower values of rainfall. During the other months, it can be employed branch pruning without fruit production, as occurs in other tropical locations of Brazil. =A videira tem sido cultivada em diferentes regiões tropicais do Brasil. No estado de Roraima, ela foi implantada comercialmente em 2005 em Boa Vista. Ao contrário das regiões de clima temperado, as regiões tropicais apresentam condições térmicas para a produção de uvas durante o ano inteiro. Para se avaliar as características climáticas dos diferentes períodos do ano pode-se recorrer a diversos índices. Objetivou-se, com o presente trabalho, avaliar a aptidão climática de Boa Vista, Roraima, para o cultivo da videira, considerando-se diferentes períodos de produção ao longo do ano. Na caracterização climática, foi utilizado o Sistema de Classificação Climática Multicrit

  10. Study of the radiological procedures used in odontologic clinics of Boa Vista, Roraima, Brazil; Estudo dos procedimentos radiologicos nos consultorios odontologicos de Boa Vista, Roraima

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    Costa, Jaberson Luiz Leitao

    2002-04-01

    The purpose of this study was to evaluate the radiological procedures used at the odontologic clinics of Boa Vista, Roraima-Brazil. The following parameters were recorded: field diameter, half value layer, total filtration, discrepancy between the preset and the applied kilovoltage and exposure time. Dose to the patient's skin from radiography of the upper molar tooth was also estimated. The results showed that 78% of the inspected units had field diameters larger than 6,0 cm, which is outside the limits recommended by the Brazilian Health Ministry. The results also showed that 14% of the equipment presented a discrepancy of more than 10% between preset and applied kilovoltage. On the other hand, the discrepancy between preset and applied exposure time is higher than 10% in 70% of the tested units. The total filtration of 77% units is lower than 1,5 mm of Al, a value recommended by the Brazilian Health Ministry for equipment that operates in the range of 50 kV to 70 kV. The survey also indicates that for 35% of the units the entrance dose in high than 3,5 mGy that is the reference value established by the Brazilian Health Ministry for dental radiography with film type. It was observed that the majority of the clinics use neither aprons nor collars for patients and that films are processed manually, without controlling temperature or processing time. Based on the results obtained it is strongly recommended that a quality control program be implemented in dental radiological clinics in Boa Vista, Roraima. (author)

  11. Two new endangered species of Anomaloglossus (Anura: Aromobatidae) from Roraima State, northern Brazil.

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    Fouquet, Antoine; Souza, Sergio Marques; Nunes, Pedro M Sales; Kok, Philippe J R; Curcio, Felipe Franco; De Carvalho, Celso Morato; Grant, Taran; Rodrigues, Miguel Trefaut

    2015-03-05

    We describe two new species of Anomaloglossus from Roraima State, Brazil, that are likely endemic to single mountains currently isolated among lowland forest and savanna ecosystems. The first species, Anomaloglossus tepequem sp. nov. was collected in 1986 and 1992 along a single stream at >500 m elevation on a tepui-like mountain named Tepequém, but was not detected during recent investigations. It is mainly diagnosed from other Anomaloglossus species by its well developed foot webbing, immaculate cream abdomen colouration and small body size (males: 18.2-20.1 mm, females: 21.7-24.5). The second species, Anomaloglossus apiau sp. nov. was found along several streams between 500 and 1400 m elevation on Serra do Apiaú, and is mainly diagnosed from congeners by its weakly webbed feet, males with swollen third finger and ventrolateral stripe formed by white dots, and its advertisement call; a long trill (up to almost 40 s) consisting of pairs of very short pulses. The discovery of these two apparently microendemic species suggests that additional Anomaloglossus species remain to be described in the Guiana Shield. Both species should be considered critically endangered given their seemingly reduced range size, association with highland habitat, and the anthropogenic pressure they currently face.

  12. Stratigraphy of the Roraima Supergroup along the Brazil-Guyana border in the Guiana shield, Northern Amazonian Craton - results of the Brazil-Guyana Geology and Geodiversity Mapping Project

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    Nelson Joaquim Reis

    Full Text Available ABSTRACT: The Geological and Geodiversity Mapping binational program along the Brazil-Guyana border zone allowed reviewing and integrating the stratigraphy and nomenclature of the Roraima Supergroup along the Pakaraima Sedimentary Block present in northeastern Brazil and western Guyana. The area mapped corresponds to a buffer zone of approximately 25 km in width on both sides of the border, of a region extending along the Maú-Ireng River between Mount Roraima (the triple-border region and Mutum Village in Brazil and Monkey Mountain in Guyana. The south border of the Roraima basin is overlain exclusively by effusive and volcaniclastic rocks of the Surumu Group of Brazil and its correlated equivalent the Burro-Burro Group of Guyana.

  13. Faunistic analysis of the species of Anastrepha Schiner (Diptera: Tephritidae in three municipalities of the state of Roraima, Brazil

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    AL. Marsaro Júnior

    Full Text Available The purpose of this work was to describe the population patterns of Anastrepha in three municipalities of the state of Roraima, Brazil, via faunistic analysis. Weekly collections were performed from January through December 2008, using McPhail traps containing 5% hydrolysed protein, in domestic orchards in the municipalities of Boa Vista, Bonfim and Pacaraima. We captured 301 females of Anastrepha in Boa Vista, 212 in Bonfim, and 167 in Pacaraima. Boa Vista presented the highest species richness (S = 10 and Pacaraima the lowest (S = 4. Anastrepha striata was the predominant species in Boa Vista (47.18% and Pacaraima (65.87%, whereas A. obliqua predominated in Bonfim (46.23%. Boa Vista presented the highest Shannon-Wiener diversity index (H' = 1.19 and Margalef index (α = 1.58, and Bonfim presented the highest Pielou's evenness index (J' = 0.69. In Pacaraima the cumulative curves reached stability, confirming that the observed and expected species richness were the same. In the other two municipalities, the curves showed a moderate growth, suggesting that the sampling effort was not sufficient to produce an accurate depiction of species richness. In this study, Anastrepha zernyi is reported for the first time in Roraima.

  14. Floristic survey of herbaceous and subshrubby aquatic and palustrine angiosperms of Viruá National Park, Roraima, Brazil.

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    Costa, Suzana Maria; Barbosa, Tiago Domingos Mouzinho; Bittrich, Volker; do Amaral, Maria do Carmo Estanislau

    2016-01-01

    We provide and discuss a floristic survey of herbaceous and subshrubby aquatic and palustrine angiosperms of Viruá National Park (VNP). The VNP is located in the northern Amazon basin and displays phytophysiognomies distributed in a mosaic where these plants occur, as flooded forests, hydromorphic white-sand savannas, "buritizais" and waterbodies. After expeditions between February/2010 and January/2015 and the analysis of specimens from regional herbaria, we list 207 species of herbaceous and subshrubby aquatic and palustrine angiosperms for the VNP, distributed in 85 genera in 37 families. We recorded six new occurrences for Brazil, two for the northern Brazilian region and 21 for Roraima state. These new occurrences, added to the other species listed here, highlight the floristic similarity between the study site and the Guiana Shield, an adjacent phytogeographical unit and geologically related to the origin of white-sand savannas.

  15. Análise Econômica da Apicultura no Estado de Roraima. = Economic analysis of the Beekeeping in the Roraima State – Brazil.

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    Ariosmar M. Barbosa

    2007-12-01

    Full Text Available Apresenta-se uma análise preliminar da economia da apicultura no estado de Roraima, com descritivos históricos desde o início da atividade apícola roraimense até 2006. Fez-se uma breve contextualização dos mercados apícolas internacional, nacional e regional. Apresenta-se um descritivo da marca Roraimel e das ações das cooperativas dos municípios de Boa Vista, Cantá e Mucajaí. = This article introduces a preliminary economy analysis of beekeeping in the State of Roraima, altogether with its historical description since the beginning of the Roraima´s beekeeping activity up to 2006. It presents a brief introduction of the international, national and regional beekeeping markets. The article also includes a brief description of the trade mark Roraimel, as well as the actions of the beekeeping cooperatives of Boa Vista, Cantá and Mucajaí districts.

  16. Analysis of the sustainability of tourism: a study in indigenous communities of Roraima state, Brazil

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    Cristiane do Nascimento Brandao

    2015-12-01

    Full Text Available This survey was conducted in three indigenous communities in the state of Roraima. They found in tourism a way of achieving local sustainable development. This activity can bring positive and negative consequences, so the aim of this study is to analyze the social, cultural, economic and environmental impacts of tourism in indigenous communities. We used the quantitative method with questionnaires. The units of analysis were the indigenous inhabitants of the surveyed communities. The survey sample consisted of 210 valid responses. In the data analysis, we used descriptive statistics and multivariate analysis. The study found that tourism can bring economic, social, cultural and environmental benefits for communities. Must develop actions that aim to transform existing initiatives in destinations of excellence in Indigenous tourism.

  17. Species of Anastrepha (Diptera: Tephritidae) captured in a guava orchard (Psidium guajava L., Myrtaceae) in Boa Vista, Roraima, Brazil.

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    Marsaro Júnior, A L; Deus, E G; Ronchi-Teles, B; Adaime, R; Silva Júnior, R J

    2013-11-01

    The guava fruit (Psidium guajava) is among the most strongly affected by fruit flies in Brazil. In the Brazilian Amazon, 11 species of Anastrepha have been reported in guava orchards to date. This work aimed to identify the species of Anastrepha present in a guava orchard in the municipality of Boa Vista, determine the species infesting the fruits, and identify any parasitoids present. Two McPhail traps with food bait were installed and weekly collections were made between January and December 2008. Fruits were also collected systematically during this period, with a view to determining the association between host plant and tephritid species. Nine species of Anastrepha were identified, in addition to one specimen belonging to a probable new species. Anastrepha striata Schiner, Anastrepha sororcula Zucchi, Anastrepha obliqua (Macquart), and Anastrepha fraterculus (Wiedemann) were the dominant species in the orchard, accounting for 84.8% of all captured individuals. All females collected directly from fruits were A. striata. Doryctobracon areolatus (Szépligeti) was the only parasitoid species obtained. In this work, Anastrepha ethalea (Walker) is reported for the first time in the state of Roraima.

  18. An illustrated key to nymphs of Perlidae (Insecta, Plecoptera genera in Central Amazonia, Brazil

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    Hamada Neusa

    2003-01-01

    Full Text Available An illustrated key to nymphs of Perlidae collected in streams of Central Amazonia, Brazil is provided. Three genera are reported for this region: Macrogynoplax Enderlein, Anacroneuria Klapálek and Enderleina Jewett. Additional diagnostic characters are provided for Enderleina nymphs.

  19. Phenology of brazil nut (Bertholletia excelsa Humb.& Bonpl., Lecythidaceae in south of Roraima state

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    Helio Tonini

    2011-03-01

    Full Text Available This work was carried out in order to study the phenological pattern of brasil-nut trees in natural forest located in the south of Roraima state, in order to relate the frequency of occurrence of phenophases with rainfall. For the phenological survey 20 adult trees (DBH > 50 cm were selected in a permanent sample plot of 9 ha. The phenological observations occurred fortnightly from February 2006 to February 2009, when data were collected on the presence or absence of events of flowering, fruiting, leaf flushing and leaf fall for each tree. The Index of population synchrony was used for estimating the synchrony of phenological events. The flowering of brasil-nut proved to be regular, annual, long and synchronous and was correlated with the reduction of rainfall. The fruiting was regular and synchronous, and dispersal was correlated with rainfall reduction. The phenological pattern of leaf flushing tended to vary yearly, being around the continual one in 2007 and bimodal in 2006 and 2008. It was noticed a higher proportion of trees falling leaves between August and October which characterizes a period of transition between the dry and the rainy time with sensitive reduction of rainfall.

  20. Oil palm vegetative development under savanna and forest ecossystems of Roraima, Brazil. = Desenvolvimento vegetativo da palma de óleo em ecossistemas de savana e floresta de Roraima.

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    Francisco Clemilto da Silva Maciel

    2011-12-01

    Full Text Available The objective of this work was to assess field vegetative development of oil palm comercial hibrids up to age of 18 months, in two ecosystems of Roraima. Two essays are being conducted, one of them in area of savanna and the other in deforested area with assessment of commercial hybrids BRS 2528, BRS 3701 and BRS 2301, under experimental design of completely random blocks with six replicates. Monthly measurements, which began 14 months after field planting, took place concerning to number of emitted leaves, width of leaf nr.4 (cm, plant hight (cm and ground level stem diameter (cm. Individual and conjoined variance analysis were performed, considering the effects of hybrids and periods as fixed and the others as aleatory. For comparison of estimated averages of assessed characteristics, Tukey test at level of 5% probability was used. As to detect alterations relative to characteristics during the period of study, concerning each environment, regression equations were estimated, the assessed characteritic being the dependent variable and the measurement epochs being the independent variable. One may conclude that, in deforested areas, hybrids show higher vegetative development than those obtained in savanna; hybrids BRS 2528, BRS 3701 and BRS 2301 showed vegetative development equivalent in savana and hibrid BRS 2301 outstanded from the others in deforested area.

  1. Control of insect pests of cowpea in the savanna of Roraima, Brazil. = Controle de insetos-praga do feijão-caupi na savana de Roraima.

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    Deyse Cristina Oliveira da Silva

    2011-12-01

    Full Text Available The objective of this study was to evaluate the effects of the insecticides acephate, imidacloprid and neem oil to control major insect pests of cowpea in cerrado of Roraima. The experiment was installed in the experimental area of the CCA/UFRR. The planting of cowpea (c.v. BRS Guariba was carried out between the double rows of cassava (2.0 x 0.8 x 0.8 m. The rows of cowpea were spaced 0.5 m apart and 0.75 m double rows of cassava. We adopted the experimental design of randomized blocks with five treatments and four replications. The treatments were as follows: T1 - control (without application of products, T2 - Neem oil ( applied to 20, 30, 40 and 50 days after planting - DAP, T3 - Imidacloprid (20 DAP + Acephate (30 DAP + Imidacloprid (40 DAP + Acephate (50 DAP, T4 - Acephate (20 DAP + Imidacloprid (30 DAP + Acephate (40 DAP + Imidacloprid (50 DAP T5 - Imidacloprid (20 DAP + Oil nim (30 DAP + Acephate (40 DAE + neem oil (50 DAP. It measured the number of plants located in the middle row with symptoms of pest attack, and the calculation of the percentage of plants attacked. It was found that all treatments were effective in controlling Aphis craccivora, the best treatments for control of Chalcodermus bimaculatus were those who had been cunning application of neem oil, that the treatment using only the neem oil was effective in controlling Aphis craccivora, Bemisia tabaci, Empoasca kraemeri and the Chalcodermus bimaculatus. The treatments used in this study were not effective to control the Cerotoma arcuatus.

  2. Árvores frutíferas nos quintais urbanos de Boa Vista, Roraima, Amazônia brasileira Fruit trees in urban home gardens of Boa Vista, Roraima, Brazilian Amazonia

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    Rui Jorge da Conceição Gomes Semedo

    2007-01-01

    Full Text Available O objetivo do trabalho foi estimar a riqueza e a diversidade das espécies de árvores frutíferas cultivadas nos quintais caseiros da cidade de Boa Vista, Roraima, bem como determinar quais são as espécies cultivadas preferencialmente pela população urbana local. Os levantamentos foram realizados em dois bairros surgidos com a expansão da cidade em 1982: (1 BEst - Bairro dos Estados (Zona Norte e (2 BAsa - Bairro Asa Branca (Zona Oeste. Foram observados 722 quintais no BEst (06 a 22.03.2004 e 339 no BAsa (07.04 a 01.07.2004. Trinta e seis espécies (19 famílias botânicas foram encontradas no BEst e 37 (20 famílias no BAsa, configurando um total de 43 espécies (20 famílias observadas. Deste total, 30 espécies (69,8% de 19 famílias (95% ocorreram em ambos os bairros, sugerindo preferências frutíferas comuns. Os três maiores índices de valor de preferência (IVP foram coincidentes e registrados para coco (Cocos nucifera L. - BEst: 19,4% e BAsa: 20,5%, manga (Mangifera indica L. - BEst: 14,9% e BAsa: 22,5% e jambo (Syzygium malaccence (L. Merr. & L.M. Perry - BEst: 10,5% e BAsa: 10,1%, todos de origem externa à Amazônia, mas que congregaram conjuntamente 44,9% (BEst e 53,0% (BAsa de IVP. Estes resultados sugerem que o cultivo de árvores frutíferas em quintais caseiros de Boa Vista segue um padrão que concentra a escolha em poucas espécies, não-originárias da Amazônia, mas tradicionalmente consagradas por seu êxito na produção de frutos.The objective of this study was to estimate the richness and the diversity of fruit tree species cultivated in Boa Vista's home gardens, as well as to determine what species the local urban population prefers. Two neighborhoods that originated during the city's expansion in 1982 were sampled: (1 BEst - Bairro dos Estados (North Zone and (2 BAsa - Bairro Asa Branca (West Zone. Seven hundred and twenty-two home gardens were surveyed in BEst (March 6 to 22, 2004, and 339 in BAsa (April 7 to

  3. Brazil nut harvesting in Peruvian Amazonia from the perspective of ecosystem services

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    Risto Kalliola

    2011-01-01

    Full Text Available Brazil nuts are harvested from the primary rainforests in the Amazonian lowlands as a direct form of sustainably using the region’s biological resources. We analyze the ecological economics of Brazil nut production in the Peruvian region of Madre de Dios where nut extraction occurs on hundreds of small-holder concessions operating under long-term agreements. This activity sustains locally important economies that suffer from small volumes and high seasonality. The size and the remoteness of the NTFP concession determine much of its profitability to concessionaires. Seasonality of the harvest generates short-term income peaks for the majority of collectors. The fragility of the Brazil nut economy in the region is compounded by volatile market prices and the overall development pressures in Amazonia, which usually involve deforestation. Although the current regulatory mechanisms in Peru encourage long-term Brazil nut production in concessions, the income level is seldom high enough to help concession-owners to rise from poverty. Auxiliary financial support based on compensations for the non-valued ecosystem services provided by the forest-covered Brazil nut concessions could change the picture. Funds for these could come from international instruments like those of carbon emission control or debt for nature swaps. Green marketing could be developed to consider payments supporting ecosystem values as well as mechanisms supporting indigenous communities working with Brazil nuts. Appropriate indicators are needed to optimize those management, policy and trading conditions that best help to preserve the invaluable ecosystem functions and services.

  4. The snakes of the genus Atractus Wagler (Reptilia: Squamata: Colubridae) from the Manaus region, central Amazonia, Brazil

    NARCIS (Netherlands)

    Martins, M.; Oliveira, M.E.

    1993-01-01

    Taxonomic and natural history data are presented on eight species of Atractus from the Manaus region, central Amazonia, Brazil, namely: A. alphonsehogei, A. latifrons, A, major, A. poeppigi, A. schach, A. snethlageae, A. torquatus, and A. trilineatus. Four of these species are recorded for the first

  5. Leporinus trimaculatus, a new species from Amazonia, Brazil, and redescription of the sympatric Leporinus aripuanaensis (Pisces, Characiformes, Anostomidae)

    NARCIS (Netherlands)

    Garavello, Julio Cesar; Santos, dos Geraldo Mendes

    1992-01-01

    Leporinus trimaculatus n.sp. is described, and Leporinus aripuanaensis Garavello & Santos, 1981 is redescribed, both from the Aripuanã river basin, Mato Grosso state, Amazonia, Brazil. A colour pattern of two, three or more dark brown blotches on the lateral sides of the body in both species

  6. Heterotrophic components of soil respiration in pastures and forests in southwestern Amazonia, Acre, Brazil

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    Eric Atlas Davidson

    2008-12-01

    Full Text Available In this paper we present data on soil microbial biomass and heterotrophic respiration in pastures, mature and secondary forests, in order to elucidate their contribution to total CO2 flux from soil to atmosphere. The research was conducted in Southwestern Amazonia, Acre State, Brazil. Microbial biomass was estimated using a variation of the traditional fumigation-extraction method and heterotrophic respiration was measured using respirometry flasks attached to an infrared gas analyzer. Soil microbial biomass and heterotrophic respiration did not differ statistically among pastures, mature and secondary forests. These laboratory results indicate that higher CO2 fluxes from pasture soils measured in situ are probably due to higher root respiration by pasture grasses.

  7. Características Morfológicas e Agronômicas de Dez Clones de Mandioca Cultivados no Estado de Roraima. = Agronomic and morphological characterization of ten cultivated clones of cassava in the Roraima State (Brazil.

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    Cylles Zara dos Reis Barbosa

    2007-12-01

    Full Text Available A mandioca é de fácil adaptação às diferentes condições edafoclimáticas, sendo cultivada em todos os estados brasileiros. No Estado de Roraima, a cultura ocupa uma área de 5.800 ha, com uma produtividade média de 13.309 kg ha-1 de raízes. O objetivo deste trabalho foi avaliar dez clones de mandioca (Aciolina, Amazonas, Catitu, BGMC-001, BGMC-314, BGMC-358, BGMC-1130, Gabrielzinho, Garapão e Panati cultivados no Estado Roraima quanto a algumas características morfológicas e agronômicas na raiz. O delineamento experimental utilizado foi inteiramente casualizado com três repetições e dez tratamentos (clones. Cada unidade experimental foi composta por quatro plantas colhidas na área útil. As característicasavaliadas foram: o número médio de raízes por planta e massa fresca das raízes por planta, cor da farinha e a tendência farinácea das raízes e o rendimento de raiz (kg ha-1. Na avaliação das raízes comerciais o clone Aciolina apresentou 7,5 raízes por planta. Os clones BGMC-314, Catitu e Aciolina apresentaram maior massa fresca por planta, variando entre 4 e 5 kg, além das maiores estimativas de produtividade de raízes (76,66 a 86,11 t ha-1. As produtividades médias das raízes frescas obtidas para os dez clones são superiores a média da cultura (13,3 t ha-1 em Roraima. = Cassava is well adapted to different edafic-climatic conditions, being cultivated in all Brazilian states. In Roraima State, the crop occupies 5.800 ha, with an average root productivity of 13.309 kg ha-1. The objective of this study was to assess ten cassava clones cultivated in the State of Roraima (Aciolina, Amazonas, Catitu, BGMC-001, BGMC-314, BGMC-358, BGMC-1130, Gabrielzinho, Garapão and Panati concerning to some root agronomic and morphological characteristics. The experimental design was interely randomized with three replicates and ten treatments (clones. Each experimental unit consisted on four plants harvested within measuring

  8. Local perceptions of jaguar conservation and environmental justice in Goiás, Matto Grosso and Roraima states (Brazil

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    Yennie K. Bredin

    2018-01-01

    Full Text Available Wildlife conservation often leads to various conflicts with other human activities, resulting in concerns about the justice of conservation. Although species' protection – notably of large carnivores – can have negative consequences for economic interests and human well-being, environmental justice issues related to species conservation are rarely explored. In Brazil, jaguars (Panthera onca have become flagships for a series of conservation initiatives. Whereas jaguars' direct impact on cattle farming has been studied, their influence on other rural stakeholders is poorly understood. Here we study local people's views on jaguars and jaguar conservation across the Cerrado savannah and the Amazon rainforest biomes. Using Q-methodology, we identified five distinct narratives regarding jaguar conservation in relation to environmental justice issues. These were shared among fishermen, tourist guides, cattle breeders, crop farmers and jaguar hunters. Interestingly, we did not find any systematic differences in subjective views, across regions, or professions/livelihood forms. However, our results showed a strong desire among the stakeholders for more local empowerment to influence the management of both jaguars and nature where they live. Moreover, we detected a widespread discontent with the lack of consistent implementation and predictable enforcement of environmental laws. Keywords: Jaguar conservation, Environmental justice, Brazil, Q methodology, Local views

  9. Eye disease related to onchocerciasis: a clinical study in the Aratha-ú, Yanomami Tribe, Roraima State, Brazil.

    Science.gov (United States)

    Neto, Guilherme Herzog; Jaegger, Karen; Marchon-Silva, Verônica; Calvão-Brito, Regina Helena Santos; Vieira, João Batista; Banic, Dalma Maria; Maia-Herzog, Marilza

    2009-11-01

    The prevalence of ocular lesions due to onchocerciasis was evaluated among residents of the Yanomami Tribe, in the northern Amazon, Brazil, an endemic area for onchocerciasis. 83 natives were submitted to an ocular examination including an external examination, biomicroscopy, intraocular pressure measurement, and a fundus examination. Clinical, parasitological and serological tests were carried out simultaneously. The population demonstrated a high prevalence of eosinophilia, skin microfilaria (55%) and onchocercal subcutaneous nodules (35%). A high prevalence of probable onchocerciasis related eye lesions was detected. Punctate keratitis (41%) and microfilaria in the anterior chamber (39%) were found as well as other probable onchocercotic lesions-chorioretinitis (7.2%) and anterior uveitis (6.0%). Other anterior eye lesions (corneal leucomas, conjunctival injection, lid nodules) occurred in 51% of the individuals. The anterior eye lesions were more prevalent than the posterior lesions. We did not find an association of glaucoma with onchocerciasis. The prevalence of these suggestive ocular lesions strongly correlates with the cutaneous nodules and eosinophilia, suggesting that skin nodules may be an indication for an eye examination. The present study provides evidence that significant infection and eye disease due to onchocerciasis persists in certain regions of Northern South America.

  10. Atributos químicos e atividade microbiana em solos convertidos de savana para plantios de Acacia mangium Willd em Roraima. = Chemical attribuites and microbial activity in soils converted to savanna for plantations of Acacia mangium Willd. in Roraima, Brazil.

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    Moisés Mourão Júnior

    2011-04-01

    Full Text Available A atividade microbiana tem sido empregada na avaliação de solos manejados, sendo um indicador importante na caracterização de solos alterados. Nesse sentido, objetivou-se com o presente trabalho avaliar o efeito de plantios de Acacia mangium com diferentes idades sobre os atributos químicos e atividade microbiana em solos representativos da Savana do Estado de Roraima. Os plantios de A. mangium de três e cinco anos encontravam-se em áreas de LATOSSOLO AMARELO Distrófico e os de quatro e seis anos em ARGISSOLO AMARELO Distrófico. As áreas próximas aos plantios com as mesmas condições de solos e com cobertura vegetal primária (savana natural constituiram as testemunhas. Foram amostrados os horizontes A e B sendo avaliados os atributos químicos dos solos e a atividade microbiana. A pobreza química e elevadasaturação por alumínio (%m dos solos estudados influenciaram significativamente nos menores valores de C-CO2 evoluído pela atividade microbiana. A maior atividade microbiana ocorreu em áreas plantadas independentemente do tipo de solo, em função das melhores condições químicas. Os maiores valores de C-CO2 evoluído correlacionaram-se melhor com os teores de carbono orgânico e matéria orgânica do solo. = Microbial activity has been used in the evaluation of soils, an important indicator in the characterization of alteredsoils. Therefore, this study has as aim to evaluate the effect of replacing natural vegetation to plantations of Acacia mangium onmicrobial activity in soils of savannas in Roraima state. The areas studied consisted of plantations of acacia with three and fiveyears in Yellow Latosol with four and six years in yellow Alfisols. Areas near the plantations with the same conditions of soiland vegetation (natural savanna were considered control. Were sampled the A and B horizons, corresponding depths 0-30 and 30-60 cm respectively, with three replications for a total of 36 experimental units. The results

  11. On the possibility of autochthonous Chagas disease in Roraima, Amazon region, Brazil, 2000-2001 Sobre a possibilidade da ocorrência de doença de Chagas autóctone em Roraima, Amazônia brasileira, 2000-2001

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    José Francisco Luitgards-Moura

    2005-02-01

    Full Text Available Chagas disease has been almost entirely eradicated from the arid zones in Central and Northeastern Brazil where rare or no autochthonous cases have been reported. However, in the last 10 years the disease has increasingly been registered in the Amazon Region. Aiming to investigate the possibility of the occurrence of autochthonous cycle of Chagas disease in Roraima, triatomine collections, vectorial susceptibility studies (this one to be shown elsewhere, parasitological and serological analyses were conducted in three agricultural settlement areas (Rorainópolis, Passarão Project and Ilha Community. Blood-donor candidates were also investigated. This is the first epidemiological survey on Chagas disease conducted in agricultural settlements in Roraima. Triatomine species found were Triatoma maculata, Rhodnius pictipes, Rhodnius robustus and Panstrongylus geniculatus. Trypanosoma cruzi detection analyses included xenodiagnosis, indirect immunofluorescence, indirect hemaglutination, ELISA and kinetoplast PCR amplification. Natural triatomine infection was not found in intestinal contents. Twenty-five adult settlers (1.4% out of 1821, all > 15 year-old, 20 migrants presented anti-T. cruzi antibodies. Two migrant settlers (from Minas Gerais and Maranhão tested positive for more than two serological tests, besides either being positive for xenodiagnosis or PCR. Results show that Chagas disease is not endemic in the areas studied. However, all elements of the transmission cycle are present, demanding for an adequate and continuous vigilance.A doença de Chagas foi quase inteiramente erradicada das zonas áridas do Brasil Central e Nordeste, onde ciclos autóctones de transmissão praticamente inexistem. Contudo, na última década a doença vem sendo registrada na Região Amazônica. Objetivando investigar a possibilidade da ocorrência de ciclos autóctones de transmissão em áreas de colonização agrícola no Estado de Roraima, foram realizadas

  12. The stratigraphy and regional structure of Miocene deposits in western Amazonia (Peru, Colombia and Brazil), with implications for late Neogene landscape evolution

    NARCIS (Netherlands)

    Wesselingh, F.P.; Hoorn, M.C.; Guerrero, J.; Räsänen, M.E.; Romero Pittmann, L.; Salo, J.A.

    2006-01-01

    A biozonation based on molluscs is proposed for Miocene deposits of western Amazonia (Peru, Colombia and Brazil), commonly referred to as the Pebas Formation. The new zonation refines existing pollen zonations and provides a key for the quick assessment of the stratigraphic position of Neogene

  13. Vírus dengue em larvas de Aedes aegypti e sua dinâmica de infestação, Roraima, Brasil Virus dengue en larvas de Aedes aegypti y su dinámica de infestación, Roraima, Brasil Dengue virus in Aedes aegypti larvae and infestation dynamics in Roraima, Brazil

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    Julianna Dias Zeidler

    2008-12-01

    ciudad de Boa Vista (Norte de Brasil. Se instalaron dos ovitrampas por domicilio, y se removieron una semana después, mensualmente, de noviembre de 2006 a mayo de 2007. Se calcularon el índice de positividad por ovitrampa y el índice de densidad de huevos. Posterior a la eclosión de 1422 huevos colectados, se formaron 44 pools de máximo 30 larvas para evaluar presencia del virus dengue por medio de RT-PCR y hemi-nested PCR. El índice de incidencia de dengue en el período fue correlacionado con la precipitación pluvial. La asociación entre esas variables y número de huevos colectados fue analizada por el coeficiente de Pearson. RESULTADOS: Ninguno de los pools presentó positividad para el virus dengue, a pesar de que en la urbanización se presentaron elevados índices de incidencia de dengue en el período de estudio. La densidad de la población de Ae. aegypti aumentó conforme a la pluviosidad, pero no presentó correlación con los índices de incidencia de casos de dengue. CONCLUSIONES: Los resultados sugieren que la transmisión transovariana del virus en mosquitos ocurre con una frecuencia muy baja y por eso su persistencia en el medio urbano puede no depender de ese fenómeno. La población del mosquito aumentó en el período de lluvia debido a la formación de criaderos; la no correlación con el índice de incidencia del dengue se debe a la posibilidad de que ese dato es subestimado en períodos de epidemia.OBJECTIVE: To detect the presence of dengue virus in larval forms of Aedes aegypti and to associate vector presence with rainfall and incidence of disease. METHODS: Eighteen households were randomly selected for egg collection in a neighborhood of the city of Boa Vista, Roraima, in Northern Brazil. Two oviposition traps were installed per home, and removed after one week. This was repeated on a monthly basis between November 2006 and May 2007. Trap positivity rate and egg density were calculated. Following the eclosion of 1,422 eggs, 44 pools of

  14. Miocene fish faunas from the northwestern Amazonia basin (Colombia, Peru, Brazil) with evidence of marine incursions

    NARCIS (Netherlands)

    Monsch, KA

    1998-01-01

    New evidence indicates marine influences during the Miocene in the northwestern Amazonia basin. This is the first major survey of the ichthyofauna from this area in the Miocene. Fossil fish remains from taxa such as the Dasyatoidea, Myliobatoidea, Characiformes, Siluriformes and Sciaenidae are

  15. Leishmaniose visceral entre índios no Estado de Roraima, Brasil: aspectos clínicoepidemiológicos de casos observados no período de 1989 a 1993 Visceral leishmaniasis among Indians of the State of Roraima, Brazil: clinical and epidemiologic aspects of the cases observed from 1989 to 1993

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    Jorge Augusto O. Guerra

    2004-08-01

    Full Text Available Descreve-se o perfil epidemiológico da leishmaniose visceral entre índios no estado de Roraima, Brasil, baseado na ocorrência de casos humanos observados e nos inquéritos caninos e entomológicos realizados no período de 1989 a 1993. Foram registrados 82 casos humanos de leishmaniose visceral em seis dos oito municípios então existentes no estado; houve predomínio de 69,5% para o sexo masculino entre os casos observados. A maioria (52,4% dos casos foi entre crianças de zero a dez anos de idade. Registrou-se o índice de 10,3% de infecção canina natural, entre 3.773 cães examinados em 74 localidades pesquisadas. A Lutzomyia longipalpis foi encontrada nas áreas de maior prevalência da doença, em 31 localidades diferentes. Os casos humanos, caninos e vetores estão concentrados em regiões onde predominam serras e lavrados, áreas características de ocorrência da leishmaniose visceral americana. A introdução e intensificação das atividades garimpeiras na região podem ter contribuído para a introdução da doença.A description of the epidemiological profile of visceral leishmaniasis among Indians in the State of Roraima, Brazil, was based on the clinical characteristics of human and dog disease, ecological aspects of the area where the cases occurred and entomologic investigations performed from 1989 to 1993. The 82 human cases were reported in six out of eight Counties that existed then in the state; there was a 69.5% predominance of male cases among those registered and a greater (52.4% occurrence of the disease in children from zero to ten years old. The rate of natural infection was 10.3% out of 3,773 dogs examined in 74 different locations. Lutzomyia longipalpis was found in 31 areas with greater prevalence of the disease. The human and animal cases as well as the vectors were concentrated in areas where mountains and arable soil predominate, typical locations for the occurrence of American visceral leishmaniasis.

  16. Identificação de Genótipos de Feijão-caupi Tolerantes a Acidez em um Latossolo Vermelho-Amarelo do Estado de Roraima = Identification of cowpea genotypes sensitivity to acidicy conditions in an Oxisol of Roraima State (Brazil.

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    Sandra Cátia Pereira Uchôa

    2007-12-01

    Full Text Available O presente trabalho foi realizado com o objetivo de identificar genótipos de feijão-caupi (Vigna unguiculata (L Walp., tolerantes à acidez. O trabalho foi realizado em casa de vegetação localizada no Campus do Cauamé, da Universidade Federal de Roraima, utilizando um Latossolo Vermelho-Amarelo de Boa Vista-RR. Foi adotado o delineamento experimental de Blocos Inteiramente Casualizados em esquema fatorial 2 x 5 x 10 com três repetições. Os tratamentos resultaram de duas formas de localização do calcário (localizada e não-localizada, 5 profundidades (0-5; 5-10; 10-15; 15-20; 20-25 cm e 10 genótipos de feijão-caupi(IT85D-3428-4-R2,4-HM; Apiaú; Hikari Graúdo; Pretinho Precoce 1; IT85D-3428-4-3-HP; USA; UFRR Grão Verde; BRS-Mazagão; Canapum e Sempre Verde. A unidade experimental foi constituída por 2dm3 de solo, dispostos em tubo de PVC com 25cm de altura,10cm de diâmetro e duas plantas de feijão. Os tubos foram confeccionados por meio da junção de 5 anéis com 5 cm cada, sendo que no anel inferior foi colocada uma placa delgada de isopor para permitir a acomodação do solo. Aos 40 dias após a emergência, as plantas foram coletadas, sendo determinada à produção de matéria seca das raízes e parte aérea. Os genótipos IT85D-3428-4-3-HP e UFRRGRÃO VERDE foram classificados como sendo de baixa tolerância, os genótipos USA, BRS-Mazagão, IT85D-3428-4-R2,4-HM e Sempre Verde, medianamente tolerantes e os genótipos Apiaú, Hikari Graúdo, Pretinho Precoce 1 e Canapum, tolerantes à acidez.= This research was carried out objecting to identify the sensibility of cowpea (Vigna unguiculata (L Walp genotypes to acidity conditions. The experiment was installed in a greenhouse located at Campus of Cauamé (Universidade Federal de Roraima in an oxisol of Roraima State (Brazil. The experimental design adopted was a completely andomized blocks in a factorial scheme 2 x 5 x 10 with three replicates. The terms of this factorial

  17. Land use and land change dynamic analysis in southeast region of RoraimaAmazonia= Análise da dinâmica das conversões de uso e cobertura da terra na região sudeste de Roraima - Amazônia

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    Maristela Ramalho Xaud

    2016-02-01

    Full Text Available Studying the dynamics of land use and land cover is of great relevance in understanding processes involving the occupation and consolidation of territory in the Amazon region. Remote sensing and its dataanalysis tools, such as techniques for detecting change, have high exploratory potential in quantifying and qualifying land use and land cover, as well as the processes of conversion and modification. The aim of this study was to analyse the dynamics of the changes in land use and the current land cover in already modified areas in the southeast of the State of Roraima, for the periods of 1997-2004 and 2004-2010. Conversions (groupings were analysed for settlement project and road distance (BR-210 and local. The results pointed out differences between the periods under analysis for the presence of change, characterising the period of 1997- 2004 as of intense activity in clearing forested areas in relation to the following period, when changes linked to previous land use predominated. The results showed a concentration of conversions by road distance, for up to 1500 m from the roads, resulting in increased loss of biomass in the most distant areas from one period to another, and suggests that this type of conversion was occurring on private property, a fact confirmed in field interviews. From one period to another, the increase in conversions from forest to pasture in two projects (Entre Rios and Caroebe may show a tendency towards increased farming activity in the region. = O estudo da dinâmica do uso e cobertura da terra tem relevância no entendimento dos processos que envolvem a ocupação e consolidação do território na região amazônica. O sensoriamento remoto e suas ferramentas de análise de dados, como as técnicas de detecção de mudanças, têm elevado potencial exploratório na quantificação e qualificação do uso e cobertura da terra, assim como dos seus processos de conversão e modificação. Objetivou-se com o presente

  18. Geological evolution of the center-southern portion of the Guyana shield based on the geochemical, geochronological and isotopic studies of paleoproterozoic granitoids from southeastern Roraima, Brazil

    International Nuclear Information System (INIS)

    Almeida, Marcelo Esteves

    2006-01-01

    This study focuses the granitoids of center-southern portion of Guyana Shield, southeastern Roraima, Brazil. The region is characterized by two tectonic-stratigraphic domains, named as Central Guyana (GCD) and Uatuma-Anaua (UAD) and located probably in the limits of geochronological provinces (e.g. Ventuari-Tapajos or Tapajos-Parima, Central Amazonian and Maroni-Itacaiunas or Transamazon). The aim this doctoral thesis is to provide new petrological and lithostratigraphic constraints on the granitoid rocks and contribute to a better understanding of the origin and geo dynamic evolution of Guyana Shield. The GCD is only locally studied near to the UAD boundary, and new geological data and two single zircon Pb-evaporation ages in mylonitic biotite granodiorite (1.89 Ga) and foliated hastingsite-biotite granite (1.72 Ga) are presented. These ages of the protholiths contrast with the lithostratigraphic picture in the other areas of Cd (1.96-1.93 Ga). Regional mapping, petrography, geochemistry and zircon geochronology carried out in the Urad have showed widespread Paleoproterozoic calc-alkaline granitic magmatism. These granitoid rocks are distributed into several magmatic associations with different Paleoproterozoic (1.97-1.89 Ga) ages, structural and geochemical affinities. Detailed mapping, petrographic and geochronological studies have distinguished two main sub domains in the UAD. In the northern UAD, the high-K calc-alkaline Martins Pereira (1.97 Ga) and Serra Dourada S-type granites (1.96 Ga) are affected by NE-SW and E-W ductile dextral shear-zones, showing coexistence of magmatic and deformational fabrics related to heterogeneous deformation. Inliers of basement (2.03 Ga) crop out northeast of this area, and are formed by meta volcano-sedimentary sequence (Cauarane Group) and TTG-like calc-alkaline association (Anaua Complex). Xenoliths of meta diorites (Anaua Complex) and para gneisses (Cauarane Group) reinforce the intrusive character of Martins Pereira

  19. Larval biometry of Simulium rubrithorax (Diptera: Simuliidae and size comparison between populations in the states of Minas Gerais and Roraima, Brazil

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    Alvan-Aguilar Miriam Adriana

    2003-01-01

    Full Text Available The number of larval instars of Simulium (Hemicnetha rubrithorax Lutz (Diptera: Nematocera was determined using the lateral length of the head capsule. In this study 1,035 larvae, of different sizes, were measured (639 from the state of Roraima and 396 from the state of Minas Gerais. A frequency distribution analysis was carried out on the measurements of the lateral length of the head capsule to determine the number of larval instars. The limits of each instar were defined by the lower frequency of the measurements falling in a range of values, by the presence of the "egg burster" that characterizes the first larval instar, and by the developmental stage of the gill histoblast. The determination of the instar number was tested using a Student's t-test (p 0.05 were observed between them.

  20. Anuran amphibians of the urban region of Altamira (Oriental Amazonia, state of Pará, Brazil.

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    Flávio Bezerra Barros

    2009-06-01

    Full Text Available The present study aimed to take stock of the species of anurans in three localities of the urban region of Altamira, a municipal district in the west of the state of Pará (Oriental Amazonia. Collections were made between January and June of 2004. Fifteen species were recorded during the study. The family Hylidae was the most represented, with eight species. The data was compatible with the degree of conservation of the collection areas. The necessity of making new fauna inventories in all Brazilian biomes is of extreme urgency, particularly in the Amazon, given its vast extension and lack of inventories.

  1. A logística de transportes na Amazônia Ocidental: desafios, limitações e importância para o desenvolvimento do Estado de Roraima

    OpenAIRE

    Passos, Luís Henrique Santos

    2013-01-01

    This paper aims to provide a diagnosis of logistics in Western Amazonia and its implications for the development of the state of Roraima. Initially, for better elucidate the basic knowledge about the logistics, make some preliminary considerations on this important tool for organizational management, seeking to highlight the main aspects of the subject. It is said about the logistics scenario Amazon, especially Amazon Ociental, comprising the states of Amazonas, Acre, Rondônia and Roraima, hi...

  2. Land-use in Amazonia and the Cerrado of Brazil: State of Knowledge and GIS Database

    Science.gov (United States)

    Nepstad, Daniel C.

    1997-01-01

    We have assembled datasets to strengthen the LargeScale Biosphere Atmosphere Experiment in Amazonia (LBA). These datasets can now be accessed through the Woods Hole Research Center homepage (www.whrc.org), and will soon be linked to the Pre-LBA homepages of the Brazilian Space Research Institute's Center for Weather and Climate Prediction (Instituto de Pesquisas Espaciais, Centro de Previsao de Tempo e Estudos Climaticos, INPE/CPTEC) and through the Oak Ridge National Laboratory, Distributed Active Archive Center (ORNL/DMC). Some of the datasets that we are making available involved new field research and/or the digitization of data available in Brazilian government agencies. For example, during the grant period we conducted interviews at 1,100 sawmills across Amazonia to determine their production of sawn timber, and their harvest intensities. These data provide the basis for the first quantitative assessment of the area of forest affected each year by selective logging (Nepstad et al, submitted to Nature). We digitized the locations of all of the rural households in the State of Para that have been mapped by the Brazilian malaria combat agency (SUCAM). We also mapped and digitized areas of deforestation in the state of Tocantins, which is comprised largely of savanna (cerrado), an ecosystem that has been routinely excluded from deforestation mapping exercises.

  3. Feeding ecology of Auchenipterichthys longimanus (Siluriformes: Auchenipteridae in a riparian flooded forest of Eastern Amazonia, Brazil

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    Tiago Magalhães da Silva Freitas

    2011-01-01

    Full Text Available Feeding habits of the midnight catfish Auchenipterichthys longimanus collected in rivers of the Caxiuanã National Forest (Eastern Amazonia, Brazil were investigated through the different hydrological periods (dry, filing, flood and drawdown. A total of 589 specimens were collected throughout seven samplings between July 2008 and July 2009, of which 74 were young males, 177 adult males, 89 young females and 249 adult females. The diet composition (Alimentary index - Ai% was analyzed by a non-metric multidimensional scaling (nMDS and by the analysis of similarity (ANOSIM, which included 37 items grouped into nine categories (Aquatic insects, Other aquatic invertebrates, Arthropods fragment, Fish, Plant fragment, Seeds, Terrestrial insects, Other terrestrial invertebrates, and Terrestrial vertebrates. We also calculated the niche breadth (Levins index and the repletion index (RI%. Differences in the diet composition between hydrological seasons were registered, primarily on diet composition between dry and flood season, but changes related with sex and maturity were not observed. The midnight catfish showed more specialists feeder habit in the flood period (March 2009 and more generalist habits in the dry season (November 2008. The amount of food eaten by A. longimanus based on repletion index (RI%, did not differ significantly from sex and maturity. However, we evidenced differences in RI% when comparing the studied months. These results provide important biological information about the trophic ecology of auchenipterids fish. In view of the higher occurrence of allochthonous items, this research also underpins the importance of riparian forests as critical environments in the maintenance and conservation of wild populations of fish in the Amazon basin.Neste estudo foram investigados os hábitos alimentares do bagre Auchenipterichthys longimanus coletados em rios da Floresta Nacional de Caxiuanã (Amazônia Oriental, Brasil ao longo de diferentes

  4. Chemical composition of the fruit mesocarp of three peach palm (Bactris gasipaes) populations grown in central Amazonia, Brazil.

    Science.gov (United States)

    Yuyama, Lúcia K O; Aguiar, Jaime P L; Yuyama, Kaoru; Clement, Charles R; Macedo, Sonja H M; Fávaro, Deborah I T; Afonso, Claudia; Vasconcellos, Marina B A; Pimentel, Sabria A; Badolato, Elsa S G; Vannucchi, Helio

    2003-01-01

    The percent composition, soluble and insoluble food fibers, oil fatty acids and minerals were determined in the mesocarp of fruits of three peach palm (Bactris gasipaes Kunth) populations grown in Central Amazonia, Brazil. Amino acids were also determined in one of the populations. The mean protein levels ranged from 1.8 to 2.7%, lipid levels ranged from 3.5 to 11.1%, the nitrogen free fraction ranged from 24.3 to 35%, food fiber ranged from 5.2% to 8.7%, and energy ranged from 179.1 to 207.4 kcal%. All essential, as well as non-essential, amino acids were present, with tryptophan and methionine presenting the lowest mean concentrations. The mono-unsaturated oleic acid predominated in the oil, ranging from 42.8 to 60.8%, and palmitic acid was the most abundant saturated fatty acid, ranging from 24.1 to 42.3%. Among the essential fatty acids, linoleic acid was the most abundant, with a maximum of 5.4% in Pampa-8. The most important mineral elements were potassium, selenium and chromium, respectively corresponding to 12%, 9% and 9% of daily recommended allowances. Considering the nutritional potential of the fruit, we suggest its more frequent incorporation into the diet of the Amazonian population.

  5. The significance of marine microfossils for paleoenvironmental reconstruction of the Solimões Formation (Miocene), western Amazonia, Brazil

    Science.gov (United States)

    Linhares, Ana Paula; Gaia, Valber do Carmo de Souza; Ramos, Maria Inês Feijó

    2017-11-01

    Micropalaeontological studies of borehole cores 1AS-7D-AM and 1AS-8-AM, from Atalaia do Norte, Amazonas state, Brazil, support previous evidence for Miocene marine ingressions in Western Amazonia. Three marine incursion events are recorded: the first in the Early/early Middle Miocene (in both cores), the second in the late Middle/early Late Miocene (1AS-8-AM), and the third in the Late Miocene (1AS-7D-AM). The first event is characterized by exclusively mangrove taxa, and the last two present a mixture of marine, fresh, and brackish water taxa. However, at the end of the third event an increase of fluvial influence is demonstrated by the predominance of freshwater taxa. These marine incursions reached the study area through narrow and geographically limited connections, controlled by the tectonic setting, at a time between the Early/early Middle Miocene and late Middle/Late Miocene. Thereafter, fluvial conditions were reestablished before Pliocene times.

  6. Deforestation drivers in Southwest Amazonia: Comparing smallholder farmers in Iñapari, Peru, and Assis Brasil, Brazil

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    Almeyda Zambrano Angelica

    2010-01-01

    Full Text Available Broad interpretation of land use and forest cover studies has been limited by the biophysical and socio-economic uniqueness of the landscapes in which they are carried out and by the multiple temporal and spatial scales of the underlying processes. We coupled a land cover change approach with a political ecology framework to interpret trends in multi-temporal remote sensing of forest cover change and socio-economic surveys with smallholders in the towns of Iñapari, Peru and Assis Brasil, Brazil in southwest Amazonia. These adjacent towns have similar biogeophysical conditions, but have undergone differing development approaches, and are both presently undergoing infrastructure development for the new Interoceanic highway. Results show that forest cover patterns observed in these two towns cannot be accounted for using single land use drivers. Rather, deforestation patterns result from interactions of national and regional policies affecting financial credit and road infrastructure, along with local processes of market integration and household resources. Based on our results we develop recommendations to minimise deforestation in the study area. Our findings are relevant for the sustainability of land use in the Amazon, in particular for regions undergoing large-scale infrastructure development projects.

  7. The spatial distribution of Hymenoptera parasitoids in a forest reserve in Central Amazonia, Manaus, AM, Brazil

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    RB. Querino

    Full Text Available Parasitoids are of great importance to forest ecosystems due to their ecological role in the regulation of the population of other insects. The species richness and abundance of parasitoids in the forest canopy and understory, both on the borders and in the interior of a tropical forest reserve in Central Amazonia were investigated. For a 12-month period, specimen collections were made every 15 days from suspended traps placed in the forest canopy and in the understory strata, both on the border and in the interior of forest areas. A total of 12,835 Hymenoptera parasitoids from 23 families were acquired. Braconidae, Diapriidae, Mymaridae, Eulophidae, and Scelionidae were the most represented in the area and strata samples. The results indicate that there were no significant differences in the species richness or abundance of Hymenoptera between the forest borders and the inner forest. The data does show that the presence of Hymenoptera is significantly greater in the understory in both the border and interior areas than in the canopy (vertical stratification. Aphelinidae and Ceraphronidae were significantly associated with the inner forest, while the other seven families with the border of the reserve. The abundance of Hymenoptera parasitoids presented seasonal variations during the year related to the rainy and dry seasons.

  8. Nitrous oxide fluxes and nitrogen cycling along a pasturechronosequence in Central Amazonia, Brazil

    Science.gov (United States)

    B. Wick; E. Veldkamp; W. Z. de Mello; M. Keller; P. Crill

    2005-01-01

    We studied nitrous oxide (N2O) fluxes and soil nitrogen (N) cycling following forest conversion to pasture in the central Amazon near Santarém, Pará, Brazil. Two undisturbed forest sites and 27 pasture sites of 0.5 to 60 years were sampled once each during wet and dry seasons. In addition to soil-atmosphere fluxes of N...

  9. Vegetation changes and human impact inferred from an oxbow lake in southwestern Amazonia, Brazil since the 19th century

    Science.gov (United States)

    Rodríguez-Zorro, Paula A.; Enters, Dirk; Hermanowski, Barbara; da Costa, Marcondes Lima; Behling, Hermann

    2015-10-01

    Pollen and X-ray fluorescence spectrometry (XRF) analyses from a 272 cm-long sediment core of Lago Amapá, an oxbow lake in western Amazonia, reveal the first palaeoecological investigation of late Holocene sediments in Acre state, Brazil. Radiocarbon dating of older sediments failed due to re-deposition of organic material but a historical map suggests that lacustrine deposition started at 1900 AD. We detected two periods of changes in sediment and vegetation, dominated by pioneer taxa especially Cecropia. The first period around 1900 AD is documenting an initial oxbow lake, with regular fluvial input (high Ti) and low accumulation of organic matter (low inc/coh ratio). During that period Andean pollen taxa originating from Peruvian Andean headwaters were deposited. A fully lacustrine phase started about 1950 AD and is characterized by prolonged periods of stagnant water (low Fe/Mn ratio). The increase of pioneer taxa, sedimentation rates and a reduction of most of the XRF element counts point to a period during which Lago Amapá was a more isolated lake which was flooded only during exceptional severe flood events and is catching mainly anthropogenic disturbances. The extensive human influence during this period was assumed by 1) the high occurrence of pioneer taxa and the absence of charcoal which could indicate changes in vegetation possibly as a result of logging, 2) the Ca and Ti/K ratio which reflect changes to a local sediment source, and 3) comparison of Landsat images from the last 30 years which shows broad changes in vegetation cover and land transformation in the peripheral areas of the oxbow lake.

  10. Brazil's Balbina Dam: Environment versus the legacy of the Pharaohs in Amazonia

    Science.gov (United States)

    Fearnside, Philip M.

    1989-07-01

    The Balbina Dam in Brazil's state of Amazonas floods 2360 km2 of tropical forest to generate an average of only 112.2 MW of electricity. The flat topography and small size of the drainage basin make output small. Vegetation has been left to decompose in the reservoir, resulting in acidic, anoxic water that will corrode the turbines. The shallow reservoir contains 1500 islands and innumerable stagnant bays where the water's residence time will be even longer than the average time of over one year. Balbina was built to supply electricity to Manaus, a city that has grown so much while the dam was under construction that other alternatives are already needed. Government subsidies explain the explosive growth, including Brazil's unified tariff for electricity. Alternative power sources for Manaus include transmission from more distant dams or from recently discovered oil and natural gas deposits. Among Balbina's impacts are loss of potential use of the forest and displacement of about one third of the surviving members of a much-persecuted Amerindian tribe: the Waimiri-Atroari. The dam was closed on 1 October 1987 and the first of five generators began operation in February 1989. The example of Balbina points to important ways that the decision-making process could be improved in Brazil and in the international funding agencies that have directly and indirectly contributed to the project. Environmental impact analyses must be completed prior to decisions on overall project implementation and must be free of influence from project proponents. The current environmental impact assessment system in Brazil, as in many other countries, has an undesirable influence on science policy, in addition to failing to address the underlying causes of environmentally destructive development processes and inability to halt “irreversible” projects like Balbina.

  11. Distribution of throughfall and stemflow in multi-strata agroforestry, perennial monoculture, fallow and primary forest in central Amazonia, Brazil

    Science.gov (United States)

    Schroth, Götz; Ferreira da Silva, Luciana; Wolf, Marc-Andree; Geraldes Teixeira, Wenceslau; Zech, Wolfgang

    1999-07-01

    The partitioning of rain water into throughfall, stemflow and interception loss when passing through plant canopies depends on properties of the respective plant species, such as leaf area and branch angles. In heterogeneous vegetation, such as tropical forest or polycultural systems, the presence of different plant species may consequently result in a mosaic of situations with respect to quantity and quality of water inputs into the soil. As these processes influence not only the water availability for the plants, but also water infiltration and nutrient leaching, the understanding of plant effects on the repartitioning of rain water may help in the optimization of land use systems and management practices. We measured throughfall and stemflow in a perennial polyculture (multi-strata agroforestry), monocultures of peach palm (Bactris gasipaes) for fruit and for palmito, a monoculture of cupuaçu (Theobroma grandiflorum), spontaneous fallow and primary forest during one year in central Amazonia, Brazil. The effect on rain water partitioning was measured separately for four useful tree species in the polyculture and for two tree species in the primary forest. Throughfall at two stem distances, and stemflow, differed significantly between tree species, resulting in pronounced spatial patterns of water input into the soil in the polyculture system. For two tree species, peach palm for fruit (Bactris gasipaes) and Brazil nut trees (Bertholletia excelsa), the water input into the soil near the stem was significantly higher than the open-area rainfall. This could lead to increased nutrient leaching when fertilizer is applied close to the stem of these trees. In the primary forest, such spatial patterns could also be detected, with significantly higher water input near a palm (Oenocarpus bacaba) than near a dicotyledonous tree species (Eschweilera sp.). Interception losses were 6·4% in the polyculture, 13·9 and 12·3% in the peach palm monocultures for fruit and for

  12. Body size and obesity patterns in Caboclo populations from Pará, Amazonia, Brazil.

    Science.gov (United States)

    Silva, Hilton; Padez, Cristina

    2010-04-01

    In many developing countries overweight, obesity and obesity-related morbidity are becoming a problem of increasing public health importance. The purpose of this study was to investigate differences in body size and body composition with age in adults of the Caboclo populations from the Brazilian Amazon as well as to examine the prevalence of overweight and obesity in adults aged 20-75 years, taking into account recent trends for the whole country. Caboclo are genetically and culturally admixed rural peasant groups that live along the Amazon River and its tributaries in Brazil, and there are few previous studies of their health and lifestyle. A total of 304 subjects (149 males and 155 females) from two socioecologically different areas were studied. Height, weight and skinfolds (tricipital, subscapular and suprailiac) were measured; international intervals (WHO) for overweight and obesity were used. Women showed significantly lower values than men for height, weight, upper arm circumference and fat-free mass and higher values for triceps, subscapular and suprailiac skinfolds and body fat (%). In the overall sample combined overweight and obesity was 47.8% in men and 50.8% in women. When compared to recent values published for the Northern region and for the whole of Brazil, 20.5% of Caboclo women aged 20-75 years were obese, which is higher than all other populations, including other rural samples. Caboclo men showed the highest rates of obesity (9.1%) and overweight (39.1%) of any rural population from the country, including Northern Brazil. The results suggest an effect of increased Western lifestyle influence on the body composition of these Caboclo populations. Considering that these are rural populations with limited access to education and health care, the high prevalence of overweight and obesity associated with low socio-economic status makes them a vulnerable group that deserves a higher level of attention by the country's public health authorities.

  13. Desmatamento no sul do estado de Roraima: padrões de distribuição em função de projetos de assentamento do INCRA e da distância das principais rodovias (BR-174 e BR-210 Deforestation in the southern portion of the Roraima state: distribution with respect to INCRA settlement projects and distance from major highways (BR-174 and BR-210

    Directory of Open Access Journals (Sweden)

    Paulo Eduardo Barni

    2012-06-01

    Full Text Available O desmatamento na Amazônia representa, atualmente, um dos principais problemas ambientais do Brasil. A contenção deste processo requer políticas públicas baseadas no entendimento das forças que controlam, aceleram e desaceleram a perda de floresta. Para avaliar ocorrências de desmatamento no sul do Estado de Roraima foram utilizados dois buffers de 20 km de largura subdivididos em oito faixas de 2500 metros ao longo das duas principais rodovias da região: BR-174 e BR-210 em um ambiente de Sistema de Informações Geográficas - SIG. O período analisado foi entre 2001 e 2007, sendo utilizados dados de desmatamento do PRODES e análises visuais em imagens TM Landsat 5. Também foram utilizados arquivos shapefile da malha viária e de Projetos de Assentamento (PAs do Sul do Estado de Roraima, junto com observações de campo. Os resultados mostraram que os desmatamentos do período estão fortemente relacionados com a disponibilidade de estradas e com o número de famílias dentro dos PAs. O desmatamento foi maior na área da BR-210 pela presença na região de grandes proprietários e invasões de terras. O pólo madeireiro, situado à margem da BR-174, pode ter influenciado na formação de pequenas áreas de desmatamento na região de Rorainópolis. A exploração madeireira predatória e novas ocupações de terras estão acontecendo de forma rápida e desordenada. Este quadro indica forte potencial para a perda de floresta em Roraima caso o fluxo de migração para esta área aumentar, como seria esperado se Roraima for conectada ao "Arco do Desmatamento" pela reabertura da Rodovia BR-319, ligando Manaus a Porto Velho.Deforestation in the Amazon currently represents one of the greatest environmental issues in Brazil, and stopping this process requires public policies based on understanding the forces that control the forest loss in different parts of Amazonia. We evaluated deforestation in the southern portion of Roraima State using a

  14. Deforestation and Carbon Loss in Southwest Amazonia: Impact of Brazil's Revised Forest Code

    Science.gov (United States)

    Roriz, Pedro Augusto Costa; Yanai, Aurora Miho; Fearnside, Philip Martin

    2017-09-01

    In 2012 Brazil's National Congress altered the country's Forest Code, decreasing various environmental protections in the set of regulations governing forests. This suggests consequences in increased deforestation and emissions of greenhouse gases and in decreased protection of fragile ecosystems. To ascertain the effects, a simulation was run to the year 2025 for the municipality (county) of Boca do Acre, Amazonas state, Brazil. A baseline scenario considered historical behavior (which did not respect the Forest Code), while two scenarios considered full compliance with the old Forest Code (Law 4771/1965) and the current Code (Law 12,651/2012) regarding the protection of "areas of permanent preservation" (APPs) along the edges of watercourses. The models were parameterized from satellite imagery and simulated using Dinamica-EGO software. Deforestation actors and processes in the municipality were observed in loco in 2012. Carbon emissions and loss of forest by 2025 were computed in the three simulation scenarios. There was a 10% difference in the loss of carbon stock and of forest between the scenarios with the two versions of the Forest Code. The baseline scenario showed the highest loss of carbon stocks and the highest increase in annual emissions. The greatest damage was caused by not protecting wetlands and riparian zones.

  15. Deforestation and Carbon Loss in Southwest Amazonia: Impact of Brazil's Revised Forest Code.

    Science.gov (United States)

    Roriz, Pedro Augusto Costa; Yanai, Aurora Miho; Fearnside, Philip Martin

    2017-09-01

    In 2012 Brazil's National Congress altered the country's Forest Code, decreasing various environmental protections in the set of regulations governing forests. This suggests consequences in increased deforestation and emissions of greenhouse gases and in decreased protection of fragile ecosystems. To ascertain the effects, a simulation was run to the year 2025 for the municipality (county) of Boca do Acre, Amazonas state, Brazil. A baseline scenario considered historical behavior (which did not respect the Forest Code), while two scenarios considered full compliance with the old Forest Code (Law 4771/1965) and the current Code (Law 12,651/2012) regarding the protection of "areas of permanent preservation" (APPs) along the edges of watercourses. The models were parameterized from satellite imagery and simulated using Dinamica-EGO software. Deforestation actors and processes in the municipality were observed in loco in 2012. Carbon emissions and loss of forest by 2025 were computed in the three simulation scenarios. There was a 10% difference in the loss of carbon stock and of forest between the scenarios with the two versions of the Forest Code. The baseline scenario showed the highest loss of carbon stocks and the highest increase in annual emissions. The greatest damage was caused by not protecting wetlands and riparian zones.

  16. Decomposition of aquatic macrophytes from Cantá stream (Roraima, Brazil: kinetics approach Decomposição de macrófitas aquáticas do Igarapé do Cantá (Roraima, Brasil: aspectos cinéticos

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    Marcela Bianchessi da Cunha-Santino

    2010-06-01

    Full Text Available AIM: This study aimed at describing and comparing the kinetics of aerobic and anaerobic decomposition of Eleocharis interstincta, Nymphaea sp. and Montrichardia arborescens; METHODS: The samples of aquatic macrophytes and water were collected in the Cantá Stream (02° 49' 11" N and 60° 40' 24" W, Cantá, Roraima, Brazil. The plant material was dried and triturated and for each experimental condition (aerobic and anaerobic mineralization chambers were prepared with plant fragments and stream water. The volume of evolved gases in anaerobic mineralization was monitored during 78 days, while the oxygen consumption was measured for 121 days; RESULTS: The results of aerobic and anaerobic decomposition were fitted to first-order kinetics model. The oxygen consumption varied from 195.36 mg g-1 (DM for E. interstincta to 629.46 mg g-1 (DM for Nymphaea sp. The deoxygenation rate derived from mineralization of M. arborescens was higher (kD: 0.049 day-1, followed by E. interstincta (kD: 0.038 day-1 and Nymphaea sp. (kD: 0.027 day-1. For the anaerobic condition the evolution of gases presented two phases: the consumption and formation. According to temporal variations of mineralized carbon, the anaerobic decomposition of M. arborescens presents the higher mineralization coefficient (0.0047 day-1; followed by Nymphaea sp. (0.0035 d-1 and E. interstincta (0.0017 day-1; CONCLUSION: Based on these results we conclude that during the aerobic decomposition of these macrophytes, the Nymphaea sp. was responsible for the higher oxygen demand and M. arborescens generated the highest amounts of gases during the anaerobic mineralization. On average, the aerobic decay processes were 11-fold faster than anaerobic. Regarding to the materials fluxes in freshwater ecosystems, low rate of decomposition observed in anaerobic process when comparing to aerobic rates reflect that the sediment represent a very efficient sink of carbon in the organic matter cycling

  17. Ecologia global contra diversidade cultural? Conservação da natureza e povos indígenas no Brasil: O Monte Roraima entre Parque Nacional e terra indígena Raposa-Serra do Sol Global ecology versus cultural diversity? Conservation of nature and indigenous peoples in Brazil. Roraima Mount: National Park vs. Raposa-Serra do Sol Indigenous Land

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    Vincenzo Lauriola

    2003-01-01

    . Adotar a perspectiva cultural indígena para entender e esclarecer suas regras efetivas de uso e manejo dos recursos naturais pode representar o ponto de partida para desenvolver e implementar planos de manejo ecologicamente eficazes e socialmente benéficos. Redirecionar a disponibilidade ecológica global a pagar na direção dos povos indígenas representaria uma contribuição nesta direção.Nature conservation policies in different countries are increasingly linked to global ecological decision making. Examples of such linkages abound, and range from priorities and policy objectives defined in international forums and institutions to the action of global environmentally concerned NGOs, to global environmental and sustainable development funds and programmes, and new economic opportunities represented by emerging markets for global ecological services and environmental commodities. These policies often clash with the needs and rights of different populations, since the implementation of man-excluding protected areas is given priority over other models of biodiversity conservation and sustainable use. Brazil is no exception to this rule: today, nature conservation policies are entering in direct conflict with policies preserving indigenous people’s rights to cultural difference. This is happening at different levels, and in several different local contexts, from the Atlantic to the Amazon and the Guyana Shield regions. Global policy priorities and funding can contribute to explain these conflicts, as the global ecological link contributes to redefine national and local political relations. The case of Mount Roraima National Park, overlapping with the Raposa-Serra do Sol Indigenous Land, illustrates how conservation policies based on man exclusion, such as National Parks, conceived and implemented in a top-down fashion, stimulate pre-existing political and land rights conflicts. Approached through a different angle, this case also indicates a possible way to viable

  18. Distribution, feeding and ecomorphology of four species of Auchenipteridae (Teleostei: Siluriformes in Eastern Amazonia, Brazil

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    Tiago M. S. Freitas

    Full Text Available ABSTRACT Fish exhibit morphological, physiological and behavioral specializations which enable them to display different ways to explore the environments and resources. Thus, the aim of this study was to verify how four Auchenipteridae species differ in the distribution, feeding habits and morphological traits: Auchenipterichthys longimanus (Günther, 1864, Auchenipterus nuchalis (Spix & Agassiz, 1829, Tatia intermedia (Steindachner, 1877 and Trachelyopterus galeatus (Linnaeus, 1766. This study was conducted in rivers and bays of the Anapú Basin, Pará State (Brazil, where these species are abundant. Specimens were collected using gillnets, and after caught the stomachs were removed for the contents analyzes. Eighteen morphometric measurements from ten adult specimens of each species were taken, combined into fifteen ecomorphological attributes. The species distribution showed that A. longimanus was restricted to rivers, while the others were exclusively caught in the bays. All four species had their diet composed of allochthonous insects, but A. longimanus also exhibited a great frugivorous habit. The most important ecomorphological attributes were relative to the consumption of larger food items (for A. longimanus and T. galeatus and to the longer swimming capacity (for A. longimanus and T. intermedia. These morphological differences and the trophic diversity presented in this study highlighted some important information about how ecomorphological similar species behave and share resources, which may play a significant role on the coexistence of these species in the Anapú Basin.

  19. Adsorption of cadmium and copper in representative soils of Eastern Amazonia, Brazil

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    Deyvison Andrey Medrado Gonçalves

    2016-10-01

    Full Text Available Studies of heavy metals adsorption in soil play a key role in predicting environmental susceptibility to contamination by toxic elements. The objective of this study was to evaluate cadmium (Cd and copper (Cu adsorption in surface and subsurface soil. Samples of six soils: Xanthic Hapludox (XH1 and XH2, Typic Hapludox (TH, Typic Rhodudalf (TR, Typic Fluvaquent (TF, and Amazonian dark earths (ADE from Eastern Amazonian, Brazil. The soils were selected for chemical, physical and mineralogical characterization and to determine the adsorption by Langmuir and Freundlich isotherms. All soils characterized as kaolinitic, and among them, XH1 and XH2 showed the lowest fertility. The Langmuir and Freundlich isotherms revealed a higher Cu (H curve than Cd (L curve adsorption. Parameters of Langmuir and Freundlich isotherms indicate that soils TR, TF and ADE has the greatest capacity and affinity for metal adsorption. Correlation between the curve adsorption parameters and the soil attributes indicates that the pH, CEC, OM and MnO variables had the best influence on metal retention. The Langmuir and Freundlich isotherms satisfactorily described Cu and Cd soil adsorption, where TR, TF and ADE has a lower vulnerability to metal input to the environment. Besides the pH, CEC and OM the MnO had a significant effect on Cu and Cd adsorption in Amazon soils.

  20. New species of titi monkey, genus Callicebus Thomas, 1903 (Primates, Pitheciidae, from Southern Amazonia, Brazil

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    Julio César Dalponte

    2014-01-01

    Full Text Available The genus Callicebus is one of the most diverse Neotropical primate groups, with 31 recognized species. However, large knowledge gaps still exist regarding the diversity of this genus. Such gaps are gradually being filled due to recent intensification of sampling efforts. Several geographic distributions have been better delimited, and six new species have been described in the last 15 years. The goal of the present study is to describe a new species of Callicebus belonging to the Callicebus moloch species group, recently discovered in an area previously considered to be part of the geographic distribution of C. cinerascens. Data collection was conducted through direct observations, specimen collection and interviews with local residents during four expeditions. Specimens were deposited in the mammalian collection of the Museu Paraense Emílio Goeldi.. For a comparative evaluation, we examined specimens of the other species of the Callicebus moloch species group, especially the geographically neighboring forms, C. bernhardi and C. cinerascens. We examined 10 chromatic characters of the fur. In addition to body mass, we verified the conventional external variables and 26 craniometric variables. The new species differs from all other Amazonian Callicebus by an exclusive combination of characters, being easily distinguished by the light gray line of the forehead, dark ocher sideburns and throat, dark gray portions of the torso and flanks, and uniformly orange tail. The geographic distribution of the new species is limited by the Roosevelt and Aripuanã rivers, in the states of Mato Grosso and Amazonas, Brazil. Approximately 25% (1,246.382 ha of this area falls within conservation areas, with five areas of sustainable use (746,818 ha and three of integral protection (499,564 ha. Furthermore, a considerable portion of the distribution area is located within indigenous lands (1,555.116 ha - 32%. Therefore, 57% (2,801.498 ha of the occurrence area of

  1. Edge effect on post-dispersal artificial seed predation in the southeastern Amazonia, Brazil

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    G. Penido

    Full Text Available This paper evaluates the post-dispersal artificial seed predation rates in two areas of the southeastern Amazon forest-savanna boundary, central Brazil. We conducted the survey in a disturbance regime controlled research site to verify if exists an edge effect in these rates and if the disturbance (in this case annual fire and no fire affects seed predation. We placed 800 peanuts seeds in each area at regular distance intervals from the fragment`s edge. Data were analyzed by a likelihood ratio model selection in generalized linear models (GLM. The complete model (with effects from edge distance and site and its interaction was significative (F3=4.43; p=0.005. Seeds had a larger predation rates in fragment’s interior in both areas, but in the controlled area (no disturbance this effect was less linear. This suggests an edge effect for post-dispersal seed predation, and that disturbances might alter these effects. Even if we exclude the site effect (grouping both areas together there is still a strong edge effect on seed predation rates (F3=32.679; p>0.001. We did not verify predator’s species in this study; however, the presence of several species of ants was extremely common in the seeds. The detection of an edge effect in only a short survey time suggests that there is heterogeneity in predation rates and that this variation might affect plant recruitment in fragmented areas of the Amazon forest. Henceforth, this seed predation should be taken in consideration in reforestation projects, where the main source of plants species is from seed distribution.

  2. Edge effect on post-dispersal artificial seed predation in the southeastern Amazonia, Brazil.

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    Penido, G; Ribeiro, V; Fortunato, D S

    2015-05-01

    This paper evaluates the post-dispersal artificial seed predation rates in two areas of the southeastern Amazon forest-savanna boundary, central Brazil. We conducted the survey in a disturbance regime controlled research site to verify if exists an edge effect in these rates and if the disturbance (in this case annual fire and no fire) affects seed predation. We placed 800 peanuts seeds in each area at regular distance intervals from the fragment`s edge. Data were analyzed by a likelihood ratio model selection in generalized linear models (GLM). The complete model (with effects from edge distance and site and its interaction) was significative (F3=4.43; p=0.005). Seeds had a larger predation rates in fragment's interior in both areas, but in the controlled area (no disturbance) this effect was less linear. This suggests an edge effect for post-dispersal seed predation, and that disturbances might alter these effects. Even if we exclude the site effect (grouping both areas together) there is still a strong edge effect on seed predation rates (F3=32.679; p>0.001). We did not verify predator's species in this study; however, the presence of several species of ants was extremely common in the seeds. The detection of an edge effect in only a short survey time suggests that there is heterogeneity in predation rates and that this variation might affect plant recruitment in fragmented areas of the Amazon forest. Henceforth, this seed predation should be taken in consideration in reforestation projects, where the main source of plants species is from seed distribution.

  3. Nitrous oxide fluxes and nitrogen cycling along a pasture chronosequence in Central Amazonia, Brazil

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    B. Wick

    2005-01-01

    Full Text Available We studied nitrous oxide (N2O fluxes and soil nitrogen (N cycling following forest conversion to pasture in the central Amazon near Santarém, Pará, Brazil. Two undisturbed forest sites and 27 pasture sites of 0.5 to 60 years were sampled once each during wet and dry seasons. In addition to soil-atmosphere fluxes of N2O we measured 27 soil chemical, soil microbiological and soil physical variables. Soil N2O fluxes were higher in the wet season than in the dry season. Fluxes of N2O from forest soils always exceeded fluxes from pasture soils and showed no consistent trend with pasture age. At our forest sites, nitrate was the dominant form of inorganic N both during wet and dry season. At our pasture sites nitrate generally dominated the inorganic N pools during the wet season and ammonium dominated during the dry season. Net mineralization and nitrification rates displayed large variations. During the dry season net immobilization of N was observed in some pastures. Compared to forest sites, young pasture sites (≤2 years had low microbial biomass N and protease activities. Protease activity and microbial biomass N peaked in pastures of intermediate age (4 to 8 years followed by consistently lower values in older pasture (10 to 60 years. The C/N ratio of litter was low at the forest sites (~25 and rapidly increased with pasture age reaching values of 60-70 at pastures of 15 years and older. Nitrous oxide emissions at our sites were controlled by C and N availability and soil aeration. Fluxes of N2O were negatively correlated to leaf litter C/N ratio, NH4+-N and the ratio of NO3--N to the sum of NO3--N + NH4+-N (indicators of N availability, and methane fluxes and bulk density (indicators of soil aeration status during the wet season. During the dry season fluxes of N2O were positively correlated to microbial biomass N, β-glucosidase activity, total inorganic N stocks and NH4+-N. In our study region, pastures of all age emitted less N2O than

  4. Geological evolution of the center-southern portion of the Guyana shield based on the geochemical, geochronological and isotopic studies of paleoproterozoic granitoids from southeastern Roraima, Brazil; Evolucao geologica da porcao centro-sul do escudo das Guianas com base no estudo geoquimico, geocronologico e isotopico dos granitoides paleoproterozoicos do sudeste de Roraima, Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Marcelo Esteves

    2006-07-01

    This study focuses the granitoids of center-southern portion of Guyana Shield, southeastern Roraima, Brazil. The region is characterized by two tectonic-stratigraphic domains, named as Central Guyana (GCD) and Uatuma-Anaua (UAD) and located probably in the limits of geochronological provinces (e.g. Ventuari-Tapajos or Tapajos-Parima, Central Amazonian and Maroni-Itacaiunas or Transamazon). The aim this doctoral thesis is to provide new petrological and lithostratigraphic constraints on the granitoid rocks and contribute to a better understanding of the origin and geo dynamic evolution of Guyana Shield. The GCD is only locally studied near to the UAD boundary, and new geological data and two single zircon Pb-evaporation ages in mylonitic biotite granodiorite (1.89 Ga) and foliated hastingsite-biotite granite (1.72 Ga) are presented. These ages of the protholiths contrast with the lithostratigraphic picture in the other areas of Cd (1.96-1.93 Ga). Regional mapping, petrography, geochemistry and zircon geochronology carried out in the Urad have showed widespread Paleoproterozoic calc-alkaline granitic magmatism. These granitoid rocks are distributed into several magmatic associations with different Paleoproterozoic (1.97-1.89 Ga) ages, structural and geochemical affinities. Detailed mapping, petrographic and geochronological studies have distinguished two main sub domains in the UAD. In the northern UAD, the high-K calc-alkaline Martins Pereira (1.97 Ga) and Serra Dourada S-type granites (1.96 Ga) are affected by NE-SW and E-W ductile dextral shear-zones, showing coexistence of magmatic and deformational fabrics related to heterogeneous deformation. Inliers of basement (2.03 Ga) crop out northeast of this area, and are formed by meta volcano-sedimentary sequence (Cauarane Group) and TTG-like calc-alkaline association (Anaua Complex). Xenoliths of meta diorites (Anaua Complex) and para gneisses (Cauarane Group) reinforce the intrusive character of Martins Pereira

  5. Scientific Collaboration Along the Trinational Frontier of Brazil-Bolivia-Peru: Implications for Regional Land-Use in the MAP Region of Southwestern Amazonia

    Science.gov (United States)

    Brown, I.

    2002-12-01

    High-speed road systems are connecting southwestern Amazonia (~1.5 million km2) to Pacific and Atlantic ports as well as providing greater access to Brazilian, Bolivian and Peruvian urban markets. Coupled with this increased accessibility are ambitious governmental plans to expand production of timber, non-timber forest products, and beef, all of which are likely to modify human migrations in the region. The heart of southwestern Amazonia lies in the trinational frontier region of Madre de Dios Department/Peru, eastern Acre State/Brazil and Pando Department/Bolivia (MAP region: ~200,000 km2, ~500,000 inhabitants). The MAP region composes a global hot spot of terrestrial biodiversity and has become an axis of integration for the three countries. Faced with rapid change in socioeconomic trends, regional environmental scientists and professionals have promoted collaborative projects to analyze land use trends and their forcing functions and to supply these results to local and regional societies. In addition, they have begun to develop a regional scientific community that bridges different nationalities and specialties. The projects are both international - as they involve three countries - and local/regional as they involve institutions that are within a radius of 300 km of the border. In the past two years, LBA-sponsored activities have helped bring over 100 professionals together in the region in five MAP-oriented workshops. The research results are now influencing public policy and are being incorporated into the regional school systems with the objective of maximizing the benefits and minimizing the adverse impacts of the changing socio-economic trends on land-use and development in the MAP region.

  6. New molecular identifiers for Simulium limbatum and Simulium incrustatum s.l. and the detection of genetic substructure with potential implications for onchocerciasis epidemiology in the Amazonia focus of Brazil.

    Science.gov (United States)

    Conceição, Priscila A; Crainey, James L; Almeida, Tatiana P; Shelley, Anthony J; Luz, Sergio L B

    2013-08-01

    The Amazonia onchocerciasis focus of southern Venezuela and northern Brazil is the larger of the two remaining Latin American onchocerciasis foci where disease transmission still occurs and is often regarded as the most challenging of all the Latin American foci to eliminate onchocerciasis. The site is home to a population of over 20,000 semi-nomadic, hunter-gatherer Yanomami people and is made-up of a mosaic of rainforest and savannah ecologies, which are influenced by the area's undulating terrain and rich geological diversity. At least six blackfly vectors have been implicated in onchocerciasis transmission in this focus; however, because of the difficulty in their routine identification the relative importance of each has been obscured. Simulium limbatum and Simulium incrustatum s.l. have both been recorded as vectors in the Amazonia focus, but they are difficult to discriminate morphologically and thus the ecological range of these species, and indeed the presence of S. limbatum in the Amazonia focus at all, have remained controversial. In the work described here, we report 15 S. incrustatum s.l. CO1 sequences and 27 S. limbatum sequences obtained from field-caught adult female blackflies collected from forest and savannah localities, inside and just outside the Amazonia focus. Phylogenetic analysis with the sequences generated in this study, showed that both the S. limbatum and the S. incrustatum s.l. CO1 sequences obtained (even from specimens living in sympatry) all fell into discrete species-specific bootstrap-supported monophyletic groups and thus confirmed the utility of the CO1 gene for identifying both these species inside the Amazonia focus. As the S. limbatum-exclusive cluster included CO1 sequences obtained from forest-caught and morphologically identified specimens these results provide the clearest evidence yet of the presence of S. limbatum inside the Amazonia focus. The question, however, of whether S. limbatum is actually a vector in the focus

  7. Clinical poisoning in bovine the venom of Bothrops atrox the municipality of Oriximiná-Pará, Central Amazonia, Brazil - Case report

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    Ubaldo de Almeida Farias Junior

    2015-10-01

    Full Text Available ABSTRACT. Farias Junior U. de A. & Chalkidis H.M. [Clinical poisoning in bovine the venom of Bothrops atrox the municipality of Oriximiná-Pará, Central Amazonia, Brazil - Case report.] Envenenamento clínico de bovino por peçonha de Bothrops atrox no município de Oriximiná-Pará, Amazô- nia Central, Brasil - Relato de caso. Revista Brasileira de Medicina Veterinária, 37(3:264-268, 2015. Laboratório de Pesquisas Zoológicas, Faculdades Integradas do Tapajós, Rua Rosa Vermelha, 335, Aeroporto Velho, Santarém, PA 68010-200, Brasil. E-mail: chalkidis@hotmail.com It explains a case of poisoning bovine by Bothrops atrox, abundant snake family Viperidae, prevalent in northern Brazil, assigned as the etiological agent of over 90% of cases of snakebite in the State of Pará. Report the examination semiological and the clinical symptoms observed due to its evolution as well. Clinical signs are confronted with the findings conferred in similar cases reported by veterinarians and ranchers in the region. The treatment in this particular case was not proceeded in order to examine symptoms presented by the accuracy of these reports.

  8. The Large-Scale Biosphere-Atmosphere Experiment in Amazonia: Analyzing Regional Land Use Change Effects.

    Science.gov (United States)

    Michael Keller; Maria Assunção Silva-Dias; Daniel C. Nepstad; Meinrat O. Andreae

    2004-01-01

    The Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) is a multi-disciplinary, multinational scientific project led by Brazil. LBA researchers seek to understand Amazonia in its global context especially with regard to regional and global climate. Current development activities in Amazonia including deforestation, logging, cattle ranching, and agriculture...

  9. Floristic, edaphic and structural characteristics of flooded and unflooded forests in the lower Rio Purús region of central Amazonia, Brazil

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    Haugaasen Torbjørn

    2006-01-01

    Full Text Available Despite a natural history interest in the early 1900s, relatively little ecological research has been carried out in the Rio Purús basin of central Amazonia, Brazil. Here we describe a new study area in the region of Lago Uauaçú with an emphasis on the climate, forest structure and composition, and soil characteristics between adjacent unflooded (terra firme and seasonally inundated forests; situated within both the white-water (várzea and black-water (igapó drainage systems that dominate the landscape. The climate was found to be typical of that of the central Amazon. Várzea forest soils had high concentrations of nutrients, while terra firme and igapó soils were comparatively nutrient-poor. Terra firme forests were the most floristically diverse forest type, whereas várzea was intermediate, and igapó the most species-poor. The Lecythidaceae was the most important family in terra firme while the Euphorbiaceae was the most important in both várzea and igapó. There were significant differences between forest types in terms of number of saplings, canopy cover and understorey density. In contrasting our results with other published information, we conclude that the Lago Uauaçú region consists of a typical central Amazonian forest macro-mosaic, but is a unique area with high conservation value due to the intimate juxtaposition of terra firme, várzea and igapó forests.

  10. BR-319: Brazil's Manaus-Porto Velho highway and the potential impact of linking the arc of deforestation to central amazonia.

    Science.gov (United States)

    Fearnside, Philip M; de Alencastro Graça, Paulo Maurício Lima

    2006-11-01

    Brazil's BR-319 Highway linked Manaus, in the state of Amazonas, to Porto Velho, Rondônia, until it became impassable in 1988. Now it is proposed for reconstruction and paving, which would facilitate migration from the "Arc of Deforestation" in the southern part of the Amazon region to new frontiers farther north. The purpose of the highway, which is to facilitate transport to São Paulo of products from factories in the Manaus Free Trade Zone, would be better served by sending the containers by ship to the port of Santos. The lack of a land connection to Manaus currently represents a significant barrier to migration to central and northern Amazonia. Discourse regarding the highway systematically overestimates the highway's benefits and underestimates its impacts. A variety of changes would be needed prior to paving the highway if these potential impacts are to be attenuated. These include zoning, reserve creation, and increased governance in various forms, including deforestation licensing and control programs. More fundamental changes are also needed, especially the abandonment of the long-standing tradition in Brazil of granting squatters' rights to those who invade public land. Organizing Amazonian occupation in such a way that road construction and improvement cease to lead to explosive and uncontrolled deforestation should be a prerequisite for approval of the BR-319 and other road projects for which major impacts are expected. These projects could provide the impetus that is needed to achieve the transition away from appropriation of public land by both small squatters and by grileiros (large-scale illegal claimants). A delay in reconstructing the highway is advisable until appropriate changes can be effected.

  11. Amphibia, Anura, Microhylidae, Chiasmocleis avilapiresae Peloso and Sturaro, 2008: First record from the state of Acre, southwestern Amazonia, Brazil

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    Sampaio, P. R. M.

    2010-01-01

    Full Text Available We record for the first time the presence of Chiasmocleis avilapiresae in the state of Acre, Brazil. This microhylidfrog is found throughout Amazon in Brazil and no information about its distribution in the Acre state was reported previously.An increase on sampling efforts, revision of material housed in herpetological collections, and use of diverse herpetofaunasampling methods might reveal additional localities and more information about this species.

  12. Amphibia, Anura, Microhylidae, Chiasmocleis avilapiresae Peloso and Sturaro, 2008: first record for the state of Acre, southwestern Amazonia, Brazil

    OpenAIRE

    Sampaio, Paulo; da Silva, Talisson; Peloso, Pedro

    2016-01-01

    We record for the first time the presence of Chiasmocleis avilapiresae in the state of Acre, Brazil. This microhylid frog is found throughout Amazon in Brazil and no information about its distribution in the Acre state was reported previously. An increase on sampling efforts, revision of material housed in herpetological collections, and use of diverse herpetofauna sampling methods might reveal additional localities and more information about this species.

  13. Ocorrência de Hypsipyla grandella Zeller (Lepidoptera, Pyralidae no Sul do Estado de Roraima

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    Luiz Dionisio

    2016-08-01

    Abstract. The study aimed to record the occurrence of Hypsipyla grandella (Zeller attacking andiroba (Carapa guianensis Aubl seed, in native forest of Roraima southern region, Brazil. Among the species of economic interest in the Amazon, stands out C. guianensis, by to be native and of multiple uses, having wood and the oil extracted from seeds as the most important products. The Meliaceae family plants, as C. guianensis and Swietenia macrophylla (King, have as a major forest pest, H. grandella. The C. guianensis seeds samplings were held in February and March 2012. The seeds were selected on the ground beneath the canopy of trees, and those which had damage (holes presence, or with insects attack trace (exudation. The seeds were brought to the Agricultural Entomology laboratory, of Federal University of Roraima - UFRR, which were separated into batches of 50 seeds per municipality, totaling 200 seeds. It was observed the presence of 450 Hypsipyla larvae in the seeds, which yielded 392 (87% adults of Hypsipyla ferrealis (Hampson and 58 (13% of H. grandella. This is the first occurrence of H. grandella damaging andiroba seeds in Roraima.

  14. A Triatoma maculata (Hemiptera, Reduviidae, Triatominae population from Roraima, Amazon region, Brazil, has some bionomic characteristics of a potential Chagas disease vector Uma população de Triatoma maculata (Hemiptera, Reduviidae, Triatominae proveniente de Roraima, Amazônia, Brasil, possui algumas características bionômicas de vetor potencial de doença de Chagas

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    José Francisco Luitgards-Moura

    2005-06-01

    Full Text Available Even though Chagas disease is rare in the Brazilian Amazon, the conditions for the establishment of domiciliated cycles prevail in many areas where triatomines are of frequent occurrence. In Roraima, a previous serological and entomological survey in three agricultural settlements showed the existence of all transmission cycle elements, i.e., individuals infected by Trypanosoma cruzi, triatomine species previously found harboring T. cruzi in the broader Amazon region of neighboring countries and, domicile/ peridomicile conditions favorable to triatomine colonization. Triatoma maculata was the most frequent species, found in chicken houses in the peridomicile and sporadically within residences. Aiming to investigate the possibility of T. maculata to possess the potentiality to transmit T. cruzi in the area, bionomic characteristics were studied under laboratory conditions. These were feeding frequency, time for defecation after a blood meal, time elapsed in voluntary fasting pre- and pos-ecdysis, moulting time periods, pre-oviposition and oviposition periods and index of oviposition, incubation period, egg viability, longevity and mortality rate. Results show that the Passarão population of T. maculata should be considered a potential vector of T. cruzi since it shows a capacity to infest artificial ecotopes in the peridomicile, to carry out large number of meals during the nymphal cycle, to have a relatively short developmental cycle capable of producing 2.9 generations/year, to blood source eclecticism, to defecate immediately after the blood meal while still on the host and to the fact that has been previously found naturally infected by T.cruzi.A doença de Chagas é de rara ocorrência na Região Amazônica Brasileira, onde contudo as condições para o estabelecimento de ciclos domésticos existem. Um estudo previamente realizado em áreas de colonização agrícola no Estado de Roraima, mostrou a possibilidade de ciclos autóctones de

  15. Short-lived U and Th isotope distribution in a tropical laterite derived from granite (Pitinga river basin, Amazonia, Brazil): Application to assessment of weathering rate

    Science.gov (United States)

    Mathieu, D.; Bernat, M.; Nahon, D.

    1995-12-01

    We have analyzed samples of a 15 m thick profile weathered from the Madeira granite, located in the Pitinga basin river, north of Manaus, in the state of Amazonia, Brazil. This profile consists essentially of a yellow-red saprolite covered by a soil. U and Th concentrations are particularly high in the granite (20 and 80 μg/g respectively). Normalized element to Th concentrations indicate that Th is most resistant to chemical weathering, except to some extent in the top soil. Higher concentrations in the saprolite compared to the granite comprise a relative enrichment, resulting from a loss of mass. The saprolites are initially generated by a descending weathering front which alters the granite to a yellow-red saprolite, a second front, close to the top, turns the saprolite into a soil. Weathering has led to leaching of U. The 234U/ 238U and 230Th/ 238U isotopic ratios are in radioactive disequilibrium. Numerous nodules are present and apparently started to form at the base of the saprolite. These nodules achieve more developed form during their relative ascent until they are reached by the descending top front where they undergo dissolution. The Th and Pb are concentrated in the nodules close to the top front. The U, being more mobile, is strongly leached by the first front, and most of the remainder, freed by the second, engages in a descending flux which supplies the underlying saprolite. Using the data an attempt is made to model the isotopic distribution in the profile. We conclude that the first front has descended at a rate of 5 cm/1000 yt, and that the time needed to create the saprolite must have been around 300,000 yr.

  16. Mansonella ozzardi (Nematoda: Onchocercidae in the riverine population of the Tefé River, State of Amazonia, Brazil

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    Jansen Fernandes Medeiros

    2014-01-01

    Full Text Available Introduction: This study assessed the prevalence of Mansonella ozzardi in riverine communities of the Tefé River, Amazonas, Brazil. Methods: The prevalence of M. ozzardi was estimated by microscopic examination of thick blood smears. Results: The M. ozzardi prevalence rate was 6.3% (19/300. Filarial infection was found in 8 of the 11 communities surveyed, with prevalence rates varying from 2.5% to 22.2%. Conclusions: Tefé is a region of oil and natural gas exploration, in which there is a high turnover of workers. Migration patterns may facilitate the dissemination of mansonelliasis to other regions.

  17. Secular trends in age at menarche among Caboclo populations from Pará, Amazonia, Brazil: 1930-1980.

    Science.gov (United States)

    Silva, H P; Padez, C

    2006-01-01

    The present study is part of a large research project on growth, development, nutrition, and health of Caboclo populations from the Brazilian Amazon. The aim of this paper is to analyze the age of menarche in adolescents (N=164) and adult women (219) in the studied populations. Caboclo are admixed rural, peasant groups that live along the Amazon river and its tributaries, and there are few previous studies about them. Probit analysis of the status quo data yielded a median age at menarche of 12.29+/-1.76 years. The retrospective method was applied to recall data of the 77 post-menarcheal adolescents, yielding an average of 13.06+/-1.27 years. Number of children in the family did not show any statistical influence on age at menarche in any age group. In adult women, age at menarche decreased from 14.50 in those born in 1930 to 12.88 for those born in 1980 (F=4.371, P=0.001). The downward trend found was, on average, 0.237 year per decade in the study period. The median age at menarche in the adolescents (12.29 years) is one of the lowest values found for Central and South American populations. In the ecological context, a low age at menarche could be an adaptive advantage because it provides a greater chance for reproduction at a young age in an environment where, until recently, life expectancy was low. As has been reported for other developing countries, the change found in age at menarche in the women born from the 1930s to the 1980s is likely to be related to changes in health and nutritional factors that occurred in Brazil because this country experienced significant improvement in living standards related to education, vaccination, and health conditions, which, although not equally, reached all regions after the 1960s. Am. J. Hum. Biol. 18:83-92, 2006. (c) 2005 Wiley-Liss, Inc.

  18. Bradyrhizobium centrolobii and Bradyrhizobium macuxiense sp. nov. isolated from Centrolobium paraense grown in soil of Amazonia, Brazil.

    Science.gov (United States)

    Michel, Daniele C; Passos, Samuel R; Simões-Araujo, Jean L; Baraúna, Alexandre C; da Silva, Krisle; Parma, Marcia M; Melo, Itamar S; De Meyer, Sofie E; O'Hara, Graham; Zilli, Jerri E

    2017-07-01

    Thirteen Gram-negative, aerobic, motile with polar flagella, rod-shaped bacteria were isolated from root nodules of Centrolobium paraense Tul. grown in soils from the Amazon region of Brazil. Growth of strains was observed at temperature range 20-36 °C (optimal 28 °C), pH ranges 5-11 (optimal 6.0-7.0), and 0.1-0.5%NaCl (optimal 0.1-0.3%). Analysis of 16S rRNA gene placed the strains into two groups within Bradyrhizobium. Closest neighbouring species (98.8%) for group I was B. neotropicale while for group II were 12 species with more than 99% of similarity. Multi-locus sequence analysis (MLSA) with dnaK, glnII, recA, and rpoB confirmed B. neotropicale BR 10247 T as the closest type strain for the group I and B. elkanii USDA 76 T and B. pachyrhizi PAC 48 T for group II. Average Nucleotide Identity (ANI) differentiated group I from the B. neotropicale BR 10247 T (79.6%) and group II from B. elkanii USDA 76 T and B. pachyrhizi PAC 48 T (88.1% and 87.9%, respectively). Fatty acid profiles [majority C 16:0 and Summed feature 8 (18:1ω6c/18:1ω7c) for both groups], DNA G + C content, and carbon compound utilization supported the placement of the novel strains in the genus Bradyrhizobium. Gene nodC and nifH of the new strains have in general low similarity with other Bradyrhizobium species. Both groups nodulated plants from the tribes Crotalarieae, Dalbergiae, Genisteae, and Phaseoleae. Based on the presented data, two novel species which the names Bradyrhizobium centrolobii and Bradyrhizobium macuxiense are proposed, with BR 10245 T (=HAMBI 3597 T ) and BR 10303 T (=HAMBI 3602 T ) as the respective-type strains.

  19. Introdução e avaliação de gladíolos em ambiente de cerrado no Estado de Roraima. = The introduction and evaluation of gladiolus under Savannah (Cerrado conditions in The State of Roraima.

    Directory of Open Access Journals (Sweden)

    Rejane Lanius Boyle

    2009-07-01

    Full Text Available As plantas ornamentais de corte comercializadas no Estado de Roraima são importadas de outros Estados do Brasil ou do exterior, como por exemplo: rosas, gladíolos, crisântemos, antúrios, violetas e gérberas. Considerando a potencialidade do Estado de Roraima para o cultivo de plantas ornamentais, objetivou com este trabalho introduzir e avaliar o comportamento de três acessos de gladíolos em condições de casa de vegetação no ambiente de cerrado do Estado deRoraima. O experimento foi instalado entre os meses de setembro a novembro de 2007. O delineamento experimental foi o de blocos inteiramente casualizados, com três tratamentos e nove repetições. Os tratamentos foram três acessos de gladíolos, sendo: 1- Trader Horn; 2- White Friendship e 3- Peter Pears. As variáveis avaliadas foram: índice de germinação, altura da planta, número de dias entre a germinação e a emissão da inflorescência, número de flores por espiga e número de flores abertas por espiga para fins de corte. Os acessos Trader Horn, White Friendship e Peter Pears desenvolveram-se até a floração, tendo apresentado um ciclo comercial médio de 73 dias e oito flores por inflorescência, apresentando características de padrão comercial. = The ornamental plants of cutting marketed in the state of Roraima are imported from other states in Brazil orcountries, for example: roses, gladiolus, chrysanthemums, anthuriums, gerberas and violets. Considering the potential of thestate of Roraima to the cultivation of ornamental plants, this work objectived to introduce and evaluate the performance of threeacesses of gladiolus overhead covered in Savannah the State of Roraima. The experiment was conducted between September and November 2007. The experimental design was of randomized blocks with three treatments and nine replications. The treatments were three species of gladioli, which: 1- Trader Horn; 2 - White Friendship and 3 - Peter Pears. The variables were

  20. Características físicas, químicas e conteúdo de água em solos convertidos de savana para plantio de Acacia mangium. = Physical and chemical characteristics and soil humidity by converting savanna to Acacia mangium crop, Roraima State, Brazil.

    Directory of Open Access Journals (Sweden)

    Maria Ivonilde Leitão de Souza

    2010-06-01

    Full Text Available Os quarenta mil quilômetros quadrados de savana (cerrado em Roraima vêm sendo substituídos por agricultura, pecuária e florestamento, portanto, objetivou-se avaliar o efeito da conversão da savana nativa para plantios de Acacia mangium, com diferentes idades, em diferentes classes de solos e profundidades dos solos nas características químicas, físicas e no teor de água do solo. O trabalho foi conduzido em duas fazendas do Empreendimento Ouro Verde Agrosilvopastoril Ltda, no município do Cantá, RR, em plantios de Acacia mangium com até quatro anos de implantação comparado a condição natural (savana. As áreas situam-se em solos da classe Latossolo Amarelo distrófico (Fazenda Tuquinha e Argissolo Amarelo distrófico (Fazenda Garimpeira e as variáveis foram avaliadas nas profundidades de 0 - 30; 30 - 60 e 60 - 90 cm. As variáveis analisadas foram: pH, bases trocáveis, alumínio trocável, H+ + Al3+, fósforo, sódio, Matéria Orgânica do Solo (MOS, granulometria, densidade do solo e teor de água no solo. Em geral, os solos são de baixa fertilidade natural, verificando-se que a implantação de Acaciamangium não apresentou alterações químicas positivas no solo, revelando uma tendência de aumento da umidade do solo coma idade de plantio de Acacia mangium. = The forty thousand square kilometers of savannah (cerrado in Roraima State, Brazil, are being replaced by agriculture and forestry. The purpose of this study was to evaluate the effect of native savanna conversion to plantationsof Acacia mangium at different ages, classes and soil depths on chemical and physical attribute and water content of soil. Thisresearch was done in two farms of Ouro Verde Agrossilvopastoril Ltda., in the city of Cantá – RR, with up to four year oldAcacia mangium crops at Tuquinha`s farm and at Garimpeira`s farm, and in natural savanna conditions. The collected samples were of dystrophic yellow Latosol (Tuquinha farm and dystrophic yellow

  1. Agronomic performance of watermelon cultivars in the Cerrado region of Boa Vista, Roraima = Desempenho agronômico de cultivares de melancia no cerrado de Boa Vista, Roraima

    Directory of Open Access Journals (Sweden)

    Ignácio Lund Gabriel da Silva Carmo

    2015-10-01

    Full Text Available Production of the watermelon is important in all regions of Brazil. However, productive and qualitative information for fruit of different cultivars grown in the same environment is still scarce, especially in the State of Roraima, a fact that makes it necessary to carry out studies in order to meet this need. As a result, this study aimed to evaluate the agronomic performance of watermelon cultivars produced in the Cerrado at Boa Vista, Roraima. The experiment was conducted at the Agua Boa Experimental Farm of Embrapa Roraima, from December 2013 to February 2014. The experimental design was of randomised blocks (DBC, with six replications. The treatments comprised six watermelon cultivars: Verena, Explore, Elisa, Juliane, Crimson Sweet and Crimson Sweet Super, for which the productive, physical, chemical and physicochemical characteristics of the fruit were evaluated. There was no difference between cultivars in yield, number of fruit ha-1 or the number of fruit with a weight of between 6 and 9 kg. The cultivars differed as to physical characteristics (weight, size and number of seeds per fruit. There were differences between cultivars for all the chemical and physicochemical characteristics of the fruit. The cultivar Elisa displayed the highest levels for total soluble solids (12.58 °Brix. Fruits of the cultivars Explore and Crimson Sweet Super showed the greatest ratio between total soluble solids and titratable acidity. The fruits of the cultivars Explore and Elisa had the highest pH. The conditions of soil and climate in the Cerrado at Boa Vista favour the productive and qualitative characteristics of the cultivars being analysed. = A produção de melancia é consolidada em todas as regiões do Brasil. Porém, as informações sobre produtividade e qualidade dos frutos, de diferentes cultivares no mesmo ambiente, ainda são tímidas, sobretudo em Roraima, tornando necessária a realização de estudos para suprir essa carência. Objetivou

  2. LBA Regional Boundary for the Legal Amazon of Brazil, 8-km

    Data.gov (United States)

    National Aeronautics and Space Administration — The Legal Amazon of Brazil is defined by law to include the states of Acre, Amapa, Amazonas, Para, Rondonia, Roraima, Mato Grosso, Maranhao, and Tocantins [Fundacao...

  3. Carbon stock loss from deforestation through 2013 in Brazilian Amazonia.

    Science.gov (United States)

    Nogueira, Euler Melo; Yanai, Aurora M; Fonseca, Frederico O R; Fearnside, Philip Martin

    2015-03-01

    The largest carbon stock in tropical vegetation is in Brazilian Amazonia. In this ~5 million km(2) area, over 750,000 km(2) of forest and ~240,000 km(2) of nonforest vegetation types had been cleared through 2013. We estimate current carbon stocks and cumulative gross carbon loss from clearing of premodern vegetation in Brazil's 'Legal Amazonia' and 'Amazonia biome' regions. Biomass of 'premodern' vegetation (prior to major increases in disturbance beginning in the 1970s) was estimated by matching vegetation classes mapped at a scale of 1 : 250,000 and 29 biomass means from 41 published studies for vegetation types classified as forest (2317 1-ha plots) and as either nonforest or contact zones (1830 plots and subplots of varied size). Total biomass (above and below-ground, dry weight) underwent a gross reduction of 18.3% in Legal Amazonia (13.1 Pg C) and 16.7% in the Amazonia biome (11.2 Pg C) through 2013, excluding carbon loss from the effects of fragmentation, selective logging, fires, mortality induced by recent droughts and clearing of forest regrowth. In spite of the loss of carbon from clearing, large amounts of carbon were stored in stands of remaining vegetation in 2013, equivalent to 149 Mg C ha(-1) when weighted by the total area covered by each vegetation type in Legal Amazonia. Native vegetation in Legal Amazonia in 2013 originally contained 58.6 Pg C, while that in the Amazonia biome contained 56 Pg C. Emissions per unit area from clearing could potentially be larger in the future because previously cleared areas were mainly covered by vegetation with lower mean biomass than the remaining vegetation. Estimates of original biomass are essential for estimating losses to forest degradation. This study offers estimates of cumulative biomass loss, as well as estimates of premodern carbon stocks that have not been represented in recent estimates of deforestation impacts. © 2014 John Wiley & Sons Ltd.

  4. Soil and vegetation carbon stocks in Brazilian Western Amazonia: relationships and ecological implications for natural landscapes.

    Science.gov (United States)

    Schaefer, C E G R; do Amaral, E F; de Mendonça, B A F; Oliveira, H; Lani, J L; Costa, L M; Fernandes Filho, E I

    2008-05-01

    The relationships between soils attributes, soil carbon stocks and vegetation carbon stocks are poorly know in Amazonia, even at regional scale. In this paper, we used the large and reliable soil database from Western Amazonia obtained from the RADAMBRASIL project and recent estimates of vegetation biomass to investigate some environmental relationships, quantifying C stocks of intact ecosystem in Western Amazonia. The results allowed separating the western Amazonia into 6 sectors, called pedo-zones: Roraima, Rio Negro Basin, Tertiary Plateaux of the Amazon, Javari-Juruá-Purus lowland, Acre Basin and Rondonia uplands. The highest C stock for the whole soil is observed in the Acre and in the Rio Negro sectors. In the former, this is due to the high nutrient status and high clay activity, whereas in the latter, it is attributed to a downward carbon movement attributed to widespread podzolization and arenization, forming spodic horizons. The youthful nature of shallow soils of the Javari-Juruá-Purus lowlands, associated with high Al, results in a high phytomass C/soil C ratio. A similar trend was observed for the shallow soils from the Roraima and Rondonia highlands. A consistent east-west decline in biomass carbon in the Rio Negro Basin sector is associated with increasing rainfall and higher sand amounts. It is related to lesser C protection and greater C loss of sandy soils, subjected to active chemical leaching and widespread podzolization. Also, these soils possess lower cation exchangeable capacity and lower water retention capacity. Zones where deeply weathered Latosols dominate have a overall pattern of high C sequestration, and greater than the shallower soils from the upper Amazon, west of Madeira and Negro rivers. This was attributed to deeper incorporation of carbon in these clayey and highly pedo-bioturbated soils. The results highlight the urgent need for refining soil data at an appropriate scale for C stocks calculations purposes in Amazonia. There

  5. The advantage of hydroelectric generation in Roraima State

    International Nuclear Information System (INIS)

    Martinez, M.L.B.; Violin, A.; Martinez, C.B.; Lima, C.M.B.

    1990-01-01

    In this work a study of the viability of implementation of PCH's in north region of the state of Roraima. Comparisons between hydro and diesel electric generation, are made based in the real generating costs and a conclusion that the hydraulic presents a smaller cost than the diesel generation. (author)

  6. Microvegetation on the top of Mt. Roraima, Venezuela

    Czech Academy of Sciences Publication Activity Database

    Kaštovský, J.; Fučíková, K.; Hauer, Tomáš; Bohunická, M.

    2011-01-01

    Roč. 11, č. 1 (2011), 171-186 ISSN 1802-5439 R&D Projects: GA ČR GA206/08/0318 Institutional research plan: CEZ:AV0Z60050516 Keywords : cyanobacteria * algae * Roraima Subject RIV: EF - Botanics Impact factor: 1.327, year: 2011

  7. Caracterização de Dez Clones de Mandioca Cultivados no Estado de Roraima. = Characterization of ten cultivated clones of cassava in the Roraima State.

    Directory of Open Access Journals (Sweden)

    Cylles Zara dos Reis Barbosa

    2007-12-01

    Full Text Available A cultura da mandioca (Manihot esculenta Crantz é cultivada nas mais diversas regiões do Brasil. No Estado deRoraima, a cultura é tradicionalmente cultivada em áreas de mata e savanas por indígenas, pequenos e médios produtoresrurais. A sua produção destina-se mais ao consumo direto na forma “in natura”, de farinha e fécula para tapioca. As cultivaresde mandioca podem apresentar diferenças de adaptação a determinadas regiões e dificilmente uma mesma cultivarcomporta-se de forma semelhante em todos os ecossistemas. Assim, desenvolveu-se este estudo, visando caracterizar dezclones de mandioca (Aciolina, Amazonas, Catitu, BGMC-001, BGMC-314, BGMC-358, BGMC-1130, Gabrielzinho,Garapão e Panati cultivados no Estado Roraima quanto ao teor de amido, matéria seca, ácido cianídrico e proteína na raiz. Odelineamento experimental utilizado foi inteiramente casualizado com três repetições e dez tratamentos (clones. Cadaunidade experimental foi composta por quatro plantas colhidas na área útil. Foram avaliados os teores de amido, HCN, proteína e matéria seca na raiz. Os clones Gabrielzinho, Panati e Garapão destacaram-se em relação aos demais clones por apresentarem teores de amido acima de 30% e matéria seca acima de 35% na raiz. O clone BGMC-001 destacou-se dos demais quanto ao maior teor de proteína apresentado na raiz (2,81% e menor teor de ácido cianídrico na raiz com e sem córtex, nota 4 e 3, respectivamente.= Cassava crop is cultivated in most diverse regions of Brazil. In the State of Roraima, the crop is traditionallycultivated in forest and savanna areas by indigenous, small and medium size rural producers. Its production is destinatedmost to direct consumption in native form, as flour and starch for “tapioca”. Cassava cultivars may show differences in theiradaptation to certain regions and rarely a same cultivars will perform similarly in all ecosystems. Thus, this study wasdeveloped, as to characterize ten

  8. Características agronômicas de cultivares de melancia nas condições do cerrado de Roraima, Brasil

    Directory of Open Access Journals (Sweden)

    Edgley Soares da Silva

    2017-01-01

    Full Text Available The objective of this work was to evaluate the agronomic characteristics of twelve watermelon cultivars produced under the edaphoclimatic conditions of the cerrado of Roraima. The experiment was developed at the Embrapa Roraima Experimental Water Field. The experimental design was in randomized blocks with four replications and six plants per plot. The treatments consisted of the cultivars: Combat, Conquista, Verena, Congo, Magnum, Electra, Santa Amelia, Explore, Emperor, Crimson Select Plus, Charleston Gray Super and Omaru Yamato. The productive, seed and fruit quality characteristics were evaluated. It was concluded that the edaphoclimatic conditions of the cerrado of Roraima favor the productive and qualitative characteristics of the fruits of the watermelon cultivars analyzed. The highest productivity was found in the Crimson Select Plus cultivar, with a mean of 67848.25 kg ha-1 . The characteristics of seeds vary according to the cultivars, with the largest quantities found in 'Santa Amélia' and 'Explore' and greater mass in 'Charleston Gray Super'. Regarding fruit quality, there is no difference in soluble solids content among cultivars; however, the values found are relatively high (> 10 ºBrix. Crimson Select Plus, Santa Amélia and Explore cultivars present high potential for cultivation in the soil and climate conditions of cerrado de Roraima-Brazil. With the information obtained in this study, it allows the exploration of new cultivars, more productive and of superior quality, when compared to those currently cultivated in the region. New studies related to the subject must contemplate the acceptance of the consumer market for the cultivars with the greatest productive potential obtained.

  9. A new species of Philometra Costa, 1845 (Nematoda: Philometridae) from the freshwater fish (red piranha) Pygocentrus nattereri Kner (Characidae) in Amazonia, Brazil

    Czech Academy of Sciences Publication Activity Database

    Cárdenas, M. Q.; Moravec, František; Fernandes, B. M. M.; Morais, A. M.

    2012-01-01

    Roč. 83, č. 2 (2012), s. 137-144 ISSN 0165-5752 R&D Projects: GA ČR GBP505/12/G112 Institutional research plan: CEZ:AV0Z60220518 Keywords : Philometra * Pygocentrus * Brazil Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.260, year: 2012 http://link.springer.com/article/10.1007%2Fs11230-012-9377-4

  10. Indicadores de sustentabilidade ambiental e de saúde na Amazônia Legal, Brasil Environmental sustainability and health indicators in the Legal Amazonia, Brazil

    Directory of Open Access Journals (Sweden)

    Carlos Machado de Freitas

    2009-06-01

    Full Text Available Entre os desafios atuais para a Saúde Pública está o de estruturar sistemas de indicadores que permitam monitorar as condições e tendências da sustentabilidade ambiental e de saúde. Neste artigo procuramos enfrentar esse desafio tendo como foco de análise os estados integrantes da Macrorregião Amazônia Legal, que desde a segunda metade do século XX vem sofrendo intensos processos de mudanças sócio-econômicas, ambientais, de saúde e bem-estar. Para a reunião e análise do conjunto de indicadores adotamos o modelo Forças Motrizes, Pressão, Situação, Exposição, Efeito e Ação (FMPSEEA proposto pela Organização Mundial da Saúde. Os resultados demonstram que, ao mesmo tempo em que as forças motrizes e pressões vêm contribuindo para o crescimento econômico e populacional, resultando em melhoras de indicadores tradicionais de saúde (redução da mortalidade infantil e aumento da expectativa de vida, são grandes as desigualdades sociais e econômicas e a sobreposição dos impactos na saúde da população, em um quadro bastante heterogêneo. Além disso, a situação ambiental também aponta para um modelo de desenvolvimento insustentável para as gerações presentes e futuras, exigindo respostas dos setores ambientais e de saúde à altura dos desafios colocados na atualidade.One of the challenges for public health is to build systems of indicators that allow monitoring current conditions and trends in environmental and health sustainability. This article focuses on the Legal Amazonia macro-region, which has undergone profound socioeconomic, environmental, and health changes since the mid-20th century. The conceptual framework adopted here was the model entitled Driving Forces, Pressures, State, Exposure, Effects, and Action (DPSEEA proposed by the World Health Organization and adopted for environmental health surveillance by the Brazilian Ministry of Health. The results show that numerous motor forces and pressures

  11. Mangrove vegetation in Amazonia: a review of studies from the coast of Pará and Maranhão States, north Brazil

    OpenAIRE

    Menezes,Moirah Paula Machado de; Berger,Uta; Mehlig,Ulf

    2008-01-01

    The present study is a compilation of the literature about vegetation of mangrove forest of the north coast of Brazil. It synthesizes the knowledge about this important ecosystem and lists the currently available literature. The study focuses on the coast of Pará and Maranhão states, which are covered by a continuous belt of mangroves. The mangrove flora comprises six mangrove tree species and several associated species. Mangrove tree height and stem diameter vary as a function of abiotic loc...

  12. From the Atlantic Forest to the borders of Amazonia: species richness, distribution, and host association of ectoparasitic flies (Diptera: Nycteribiidae and Streblidae) in northeastern Brazil.

    Science.gov (United States)

    Barbier, Eder; Bernard, Enrico

    2017-11-01

    Better knowledge of the geographical distribution of parasites and their hosts can contribute to clarifying aspects of host specificity, as well as on the interactions among hosts, parasites, and the environment in which both exist. Ectoparasitic flies of the Nycteribiidae and Streblidae families are highly specialized hematophagous parasites of bats, whose distributional patterns, species richness, and associations with hosts remain underexplored and poorly known in Brazil. Here, we used information available in the literature and unpublished data to verify if the occurrence of bat hosts in a given environment influences the occurrence and distribution of nycteribiid and streblid flies in different ecoregions in the northeastern Brazil. We evaluate species richness and similarity between ecoregions and tested correlations between species richness and the number of studies in each ecoregion and federative unit. We recorded 50 species and 15 genera of bat ectoparasitic flies on 36 species and 27 genera of bat hosts. The Atlantic Forest had the highest fly species richness (n = 31; 62%), followed by Caatinga (n = 27; 54%). We detected the formation of distinct groups, with low species overlap between ecoregions for both flies and bats. Fly species richness was correlated with host species richness and with the number of studies in each federative unit, but not with the number of studies by ecoregion. Due to the formation of distinct groups with low species overlap for both groups, host availability is likely to be one of the factors that most influence the occurrence of highly specific flies. We also discuss host specificity for some species, produced an updated list of species and distribution for both nycteribiid and streblid flies with information on interaction networks, and conclude by presenting recommendations for more effective inventories of bat ectoparasites in the future.

  13. Small farmers and deforestation in Amazonia

    Science.gov (United States)

    Brondízio, Eduardo S.; Cak, Anthony; Caldas, Marcellus M.; Mena, Carlos; Bilsborrow, Richard; Futemma, Celia T.; Ludewigs, Thomas; Moran, Emilio F.; Batistella, Mateus

    This chapter discusses the relationship between small farmers' land use and deforestation, with particular attention paid to the past 30 years of Amazonian colonization in Brazil and Ecuador. Our analysis calls attention to common features uniting different social groups as small farmers (e.g., social identity, access to land and resources, technology, market, and credit), as well as the variability between small farmers in terms of time in the region (from native populations to recent colonists), contribution to regional deforestation, types of land use systems. At a regional level, small farmers contribute to the majority of deforestation events, but are responsible for only a fraction of the total deforested area in Amazonia. We discuss three misconceptions that have been used to define small farmers and their contribution to the regional economy, development, and deforestation: (1) small farmers have backward land use systems associated with low productivity and extensive deforestation and subsistence production, (2) small farmers contribute to Amazonian deforestation as much as large farmers, and (3) small farmers, particularly colonist farmers, follow an inexorable path of deforestation unless curbed by government action. We conclude the chapter discussing their growing regional importance and the need for more inclusive public policies concerning infrastructure and services and valorization of resources produced in rural areas of Amazonia.

  14. Throughfall and temporal trends of rainfall redistribution in an open tropical rainforest, south-western Amazonia (Rondônia, Brazil

    Directory of Open Access Journals (Sweden)

    S. Germer

    2006-01-01

    Full Text Available Throughfall volumes and incident rainfall were measured between 23 August and 2 December 2004 as well as from 6 January to 15 April 2005 for individual rain events of differing intensities and magnitudes in an open tropical rainforest in Rondônia, Brazil. Temporal patterns of throughfall spatial variability were examined. Estimated interception was compared to modeled interception obtained by applying the revised Gash model in order to identify sources of throughfall variability in open tropical rainforests. Gross precipitation of 97 events amounted to 1309 mm, 89±5.6% (S.E. of which reached the forest floor as throughfall. The redistribution of water within the canopy was highly variable in time, which we attribute to the high density of babassu palms (Orbignya phalerata, their seasonal leaf growth, and their conducive morphology. We identified a 10-min rainfall intensity threshold of 30 mmh-1 above which interception was highly variable. This variability is amplified by funneling and shading effects of palms. This interaction between a rainfall variable and vegetation characteristics is relevant for understanding the hydrology of all tropical rainforests with a high palm density.

  15. First Record of Lutzomyia (Lutzomyia) longipalpis (Diptera: Psychodidae: Phlebotominae) on the Trinational Frontier (Brazil-Peru-Bolivia) of South-Western Amazonia.

    Science.gov (United States)

    Borges, Diones Antonio; Molina, Silvia Maria Guerra; Pinto, Mara Cristina; Galati, Eunice Aparecida Bianchi; Cesario, Manuel; Ortiz, Dennys Ghenry Samillan

    2017-09-01

    In South America, the main sand fly species involved in the transmission of Leishmania infantum chagasi (Cunha & Chagas, 1937), etiological agent of the visceral leishmaniasis (VL), is Lutzomyia longipalpis (Lutz & Neiva, 1912). The species has been recorded in Colombia, Venezuela, Bolivia, Argentina, Paraguay, Uruguay, and Brazil, where it is recorded in 24 of the 27 Brazilian states, except Acre, Amazonas, and Santa Catarina. Collections were carried out for one year (April 2013 to March 2014) using modified CDC light traps in different environments in Assis Brasil municipality, state of Acre. Two males of Lu. longipalpis were found in peridomiciliary location in a peri-urban area. This is the first record of the species in Acre. This finding may be considered by the health agencies located in the trinational frontier, and new collections are needed to evaluate the real distribution of the species. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  16. How many species of mammals are there in Brazil? New records of rare rodents (Rodentia: Cricetidae: Sigmodontinae from Amazonia raise the current known diversity

    Directory of Open Access Journals (Sweden)

    Alexandre R. Percequillo

    2017-12-01

    Full Text Available Background Since 1996, when Vivo questioned how many species of mammals occur in Brazil, there has been a huge effort to assess this biodiversity. In this contribution, we present new records for rare species of the sigmodontine rodent genera Rhagomys and Neusticomys previously unknown to Brazilian Amazon. We provided detailed information on the morphologic variation to allow the proper identification of these species. We also furnished updated information on their collection, aiming to establish hypothesis of their geographic distribution, based on SDM’s, aiming to hypothesize potential occurrence areas for these species. Methods Rodent specimens were sampled in separate inventories in two sites of Rondônia State (Hydroelectric Dam Jirau and Parque Nacional de Pacaás Novos and one site in Pará State (Pacajá, Brazil, and were compared to specimens from museum collections to apply appropriate names. The SDM were conducted using two algorithms for rare species, MaxEnt and randomForest (RF, and were based on seven localities for Rhagomys, and 10 for Neusticomys. Results All specimens were collected with pitfall traps. One specimen of genus Rhagomys was trapped in the Hydroelectric Dam Jirau. We identified this specimen as R. longilingua, and the SDM species indicates suitable areas for its occurrence at high elevations near on the Andes and lowlands of Amazon Basin to the South of the Rio Amazonas. Two specimens of Neusticomys were recorded, and we identified the specimen from Pacaás Novos as N. peruviensis, with SDM suggesting main areas of occurrence on Western Amazon. We applied the name N. ferreirai to the specimen from Pacajá, with SDM recovering suitable areas in Eastern Amazon. Discussion We reinforced the importance of pitfall traps on the study of Neotropical rodents. We described morphologic variation within and among all species that do not invalidate their specific status, but in the near future a re-evaluation will be mandatory

  17. Implicações biogeográficas de novos registros ornitológicos em um enclave de vegetação de campina no sudoeste da Amazônia brasileira Biogeographic implications of new avian records from a patch of white-sand forest in southwestern Brazilian Amazonia

    Directory of Open Access Journals (Sweden)

    Fabíola Poletto

    2005-12-01

    growing on bleached sandy soils throughout Amazonia; despite their widespread distribution, WSF occur predominantly in the upper Rio Negro drainage (NW Brazil, SE Colombia, and S Venezuela. Smaller and isolated WSF patches located in SW. Brazilian Amazonia have not been studied systematically by ornithologists; therefore, some important ornithological results obtained during a field-trip to a WSF patch in the extreme SW. corner of the state of Amazonas, centered at 7º22'33.2"S and 73º00'42.5"W, are presented here. The first records of Hemitriccus striaticollis (Lafresnaye, 1853 (Aves, Tyrannidae and Xenopipo atronitens Cabanis, 1847 (Aves, Pipridae for SW. Brazilian Amazonia are presented, along with additional records of the following little known or rare species inhabiting this region: Formicivora grisea (Boddaert, 1783 (Aves, Thamnophilidae, Conopias parvus (Pelzeln, 1868 (Aves, Tyrannidae, and Heterocercus linteatus (Strickland, 1850 (Aves, Pipridae. As verified in WSF patches distributed throughout N. Peru, the WSF avifauna occurring in SW. Brazilian Amazonia is also highly influenced by species closely associated with the upper Rio Negro drainage. However, a second distinct biogeographic influence was also noted: that of species whose distribution's strongholds are located in central and E. Amazonia, S. of the Amazon river. The WSF avifauna of SW. Brazilian Amazonia is still poorly known; future ornithological surveys of isolated WSF patches in this region could lead to new range extensions and even to the discovery of unnamed taxa.

  18. Contribuição ao conhecimento da flora medicinal de Roraima

    OpenAIRE

    van den Berg, Maria Elisabeth; Silva, Milton Hélio Lima da

    1988-01-01

    São apresentados dados etnobotânicos sobre a flora medicinal do Território Federal de Roraima, identificando-se cientificamente as espécies encontradas em levantamentos efetuados nos municípios de Boa Vista e Caracaraí. Preliminary research on the folk medicine of Roraima Federal Territory is presented here. Botanical identification, accordin to Cronquist's sistematic classification of plant families, traditional uses and aditional data are provided. A large number of families are represen...

  19. ECOLOGICAL RESEARCH IN THE LARGE-SCALE BIOSPHERE–ATMOSPHERE EXPERIMENT IN AMAZONIA: EARLY RESULTS.

    Science.gov (United States)

    M. Keller; A. Alencar; G. P. Asner; B. Braswell; M. Bustamente; E. Davidson; T. Feldpausch; E. Fern ndes; M. Goulden; P. Kabat; B. Kruijt; F. Luizao; S. Miller; D. Markewitz; A. D. Nobre; C. A. Nobre; N. Priante Filho; H. Rocha; P. Silva Dias; C von Randow; G. L. Vourlitis

    2004-01-01

    The Large-scale Biosphere–Atmosphere Experiment in Amazonia (LBA) is a multinational, interdisciplinary research program led by Brazil. Ecological studies in LBA focus on how tropical forest conversion, regrowth, and selective logging influence carbon storage, nutrient dynamics, trace gas fluxes, and the prospect for sustainable land use in the Amazon region. Early...

  20. Ecological research in the large-scale biosphere-atmosphere experiment in Amazonia: early results

    NARCIS (Netherlands)

    Keller, M.; Alencar, A.; Asner, G.P.; Braswell, B.; Bustamante, M.; Davidson, E.; Feldpausch, T.; Fernandes, E.; Goulden, M.; Kabat, P.; Kruijt, B.; Luizão, F.; Miller, S.; Markewitz, D.; Nobre, A.D.; Nobre, C.A.; Priante Filho, N.; Rocha, da H.; Silva Dias, P.; Randow, von C.; Vourlitis, G.L.

    2004-01-01

    The Large-scale Biosphere-Atmosphere Experiment in Amazonia (LBA) is a multinational, interdisciplinary research program led by Brazil. Ecological studies in LBA focus on how tropical forest conversion, regrowth, and selective logging influence carbon storage,. nutrient dynamics, trace gas fluxes,

  1. FOREST SPECIES EVALUATION IN THE FOREST REGION IN RORAIMA STATE

    Directory of Open Access Journals (Sweden)

    Helio Tonini

    2006-03-01

    Full Text Available This study was carried out to evaluate 19 native and exotic species and to identify potential species for plantation inhomogeneous stands and in agroforestry systems in forest ecosystem in Roraima State. The species were planted from 1997 to 2000.When the objective was sawn wood production the spacing was 4 x 3 m and when the objective was energy and pulp production thespacing was 3 x 2 m. The samples consisted of 9 lines of 9 plants, totaling 81 plants, coming down to 49 useful trees. In each useful treewere measured the DBH (diameter at 1.30 m and total height. The merchantable volume per hectare was obtained with themerchantable form factor determination, through the scaling of two medium trees using the Smalian method. Each species, was alsoevaluated in relation to survival, bole quality, phytossanitary aspects and wind damages.The data analysis indicated as promisingspecies for use in energy, Eucalyptus urograndis; Schizolobium amazonicum as low or medium wood density species for use inveneer production and Bertholettia excelsa as medium to high density for use in sawn timber.

  2. Characterization of cassava clones produced in Roraima for in natura consumption. = Caracterização e identificação de clones de mandioca produzidos em Roraima para o consumo in natura.

    Directory of Open Access Journals (Sweden)

    Natália Trajano de Oliveira

    2011-12-01

    Full Text Available The objective of this study was to characterize and identify cassava clones produced in Roraima State, Brazil, for human consumption. There was the planting of six clones of cassava (Aciolina, Pão, Pão-do-Chile, Água Morna, Enxuta and Amazonas, in double rows, following the spacing of 2.0 m x 0.8 m x 0.8 m, total of 8,928 plants ha-1 . It was used randomized blocks experimental design with four replications. At eight months after planting was carried out to harvest the roots, being evaluated for hydrocyanic acid, starch content by the method of hydrostatic balance and artisanal mining, ability to release the film and bark, bark color and flesh color raw. The cassava clones were classified according to HCN content in: Mansi (Enxuta and Pão-do-Chile, intermediate (Aciolina and Água Morna and Brava (Pão and Amazonas. The starch obtained by the method of hydrostatic balance overestimates the starch content by the method artisanal mining. The Aciolina clone stood out among the clones for human consumption, it is also recommended for industrial use. The Pão and Amazonas clones have restrictions for both human consumption and for industrial used.

  3. Orchid diversity at a residual plateu on Caroebe, Roraima

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    Francisco Joaci de Freitas Luz

    2016-10-01

    Full Text Available Orchids were observed in a granitic mountain hill at the, Caroebe road 35, Roraima, at February and June of 2016. It was observed the occurrence of orchids in three different points: the base of the mountain, with typical humid tropical dry land forest; the forest around the rocky top of the mountain, with the presence of thin trees about 15 meters high, medium light entrance below the vegetation; and the granitic plateau, more sun incidence and surrounded by small shrubs. The total area surveyed was of 5 hectares. The orchids encountered in the whole trail were prior identified locally, just as their localization by GPS and according to their growth habit (epiphytic, terrestrial or rupicolous. It was found 28 species. The majority of the indivíduals identified in this survey were found on organic layers accumulated over the granitic rock, as follow: Catasetum planiceps, Catasetum discolor, Cyrtopodium andersonii, Encyclia granitica, Epidendrum ibaguense, Epidendrum viviparum, Cleistes rosea e Nohawilliamsia pirarensis. At the forest that surrounds the rocky hill it was observed, associated to small trees, the following epiphyte orchids: Dimerandra emarginata, Octomeria sp., Scaphyglottis sickii, Trigonidium acuminatum and Cattleya violacea. At the forest covering the base of the mountain it was found the larger number of species (13, with predominance of epiphytes. Besides the larger number found, the frequency of these species was very low, except for Camaridium ochroleucum and Heterotaxis superflua that were found in larger quantity associated to some sort of trees. The specie Liparis nervosa was found only associated to the base of a unique tree, over the organic matter accumulated locally. The large number of orchids found in the study area indicates its importance for more comprehensive studies and stresses the importance for conservation.

  4. Lineage Divergence Detected in the Malaria Vector Anopheles marajoara (Diptera: Culicidae) in Amazonian Brazil

    Science.gov (United States)

    2010-10-07

    species [22], but see Bourke et al [17]. Genealogical analyses of complete mtDNA COI (Cyto- chrome oxidase I) sequences found that A. marajoara is...darlingi in human malaria transmission in Boa Vista, state of Roraima, Brazil. Mem Inst Oswaldo Cruz 2006, 101:163-168. 17. Bourke BP, Foster PG

  5. A new species of phlebotomine, Trichophoromyia adelsonsouzai (Diptera: Psychodidae of Brazilian Amazonia

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    Thiago Vasconcelos dos Santos

    2014-04-01

    Full Text Available The phlebotomine sandfly Trichophoromyia adelsonsouzai sp. nov. is described and illustrated based on the male and female morphological characteristics of specimens collected at Km 27 of the Trans-Amazonian Highway, municipality of Vitória do Xingu, state of Pará, Brazilian Amazonia. This is an area subject to the direct influence of Belo Monte hydroelectric system. With the description of this new species the number of Trichophoromyia sandflies recorded in Brazil is increased to 20.

  6. The environment and the hydroelectric in Amazonia

    International Nuclear Information System (INIS)

    La Rovere, E.L.

    1992-01-01

    Some aspects about social and environmental impacts due to the hydroelectric power plants constructed in Amazonia region are presented, including considerations of energy planning and management with international example. (C.G.C.)

  7. Secondary Forests from Agricultural Abandonment in Amazonia 2000-2009

    Science.gov (United States)

    Morton, Douglas

    2010-01-01

    Ongoing negotiations to include reducing emissions from tropical deforestation and forest degradation (REDD+) in a post-Kyoto climate agreement highlight the critical role of satellite data for accurate and transparent accounting of forest cover changes. In addition to deforestation and degradation, knowledge of secondary forest dynamics is essential for full carbon accounting under REDD+. Land abandonment to secondary forests also frames one of the key tradeoffs for agricultural production in tropical forest countries-whether to incentivize secondary forest growth (for carbon sequestration and biodiversity conservation) or low-carbon expansion of agriculture or biofuels production in areas of secondary forests. We examined patterns of land abandonment to secondary forest across the arc of deforestation in Brazil and Bolivia using time series of annual Landsat and MODIS data from 2000-2009. Rates of land abandonment to secondary forest during 2002-2006 were less than 5% of deforestation rates in these years. Small areas of new secondary forest were scattered across the entire arc of deforestation, rather than concentrated in any specific region of the basin. Taken together, our analysis of the satellite data record emphasizes the difficulties of addressing the pool of new secondary forests in the context of REDD+ in Amazonia. Due to the small total area of secondary forests, land sparing through agricultural intensification will be an important element of efforts to reduce deforestation rates under REDD+ while improving agricultural productivity in Amazonia.

  8. Plant density and levels of NPK on the production components of vegetable soybean in the Savannah of the state of Roraima=Densidade de plantas e doses de NPK nos componentes de produção de soja-hortaliça na Savana de Roraima

    Directory of Open Access Journals (Sweden)

    Alynny Neftaly Lopes Monteiro

    2016-02-01

    Full Text Available The aim of this study was to evaluate the effect of two sowing densities and levels of NPK (02-24- 12 on the production components of the JLM 08 strain of vegetable soybean, in the Savannah of Boa Vista, in the state of Roraima, Brazil. The experiment was carried out from November 2013 to March 2014 in the experimental area of the Centre for Agrarian Sciences at the Cauamé Campus of the Federal University of Roraima in Boa Vista. The experimental design was of randomised blocks in a factorial scheme (2 x 5 with three replications. The two densities (40,000 and 80,000 plants per hectare comprised the first factor, while five levels of NPK (02-24-12 made up the second (0, 200, 400, 600 and 800 kg ha-1. The following were evaluated: height of insertion of the first and last pod; stem diameter; number of pods per plant having 1, 2, and 3 grains; total number of pods per plant; 100 grain weight and estimated grain yield. The height of insertion of the first and last pod in the JLM 08 genotype of the vegetable soybean is not influenced by the planting densities or levels of formulated fertiliser. At a density of 80,000 plants per hectare, the number of pods per plant is influenced by the levels of fertiliser, demonstrating a positive quadratic response. The level of fertiliser with the maximum technical efficiency (492.86 kg ha-1 gives an 18% increase in grain yield at the highest planting density. = Objetivou-se com este trabalho avaliar o efeito de duas densidades de semeadura e doses de NPK (02-24-12 nos componentes de produção da soja hortaliça linhagem JLM 08, na Savana de Boa Vista, Roraima. O experimento foi conduzido no período de novembro de 2013 a março de 2014, na área experimental do Centro de Ciências Agrária da Universidade Federal de Roraima, Campus Cauamé, em Boa Vista, Roraima. O delineamento experimental adotado foi em blocos ao acaso, em esquema fatorial (2 x 5, com três repetições. O primeiro fator correspondeu a duas

  9. Two-year participatory monitoring of extractivism in Brazilian Amazonia

    DEFF Research Database (Denmark)

    Cámara-Leret, Rodrigo; Newton, Peter; Hawes, Joseph

    basin of western Brazilian Amazonia. We discuss the most important extractive activities for ~100 households, how socio-economic factors influence NTFP extractive patterns across households, and the benefits and constraints of using participatory approaches to monitor extractivism in Amazonia....

  10. A medium-spatial scale distribution pattern of Pseudoscorpionida (Arachnida in a gradient of topography (altitude and inclination, soil factors, and litter in a central Amazonia forest reserve, Brazil

    Directory of Open Access Journals (Sweden)

    N. O. Aguiar

    Full Text Available In Amazonia, nothing is known about the distribution of the invertebrates on a medium-spatial scale pattern. In a trail system of 64 km² at Ducke Reserve, we sampled 72 transects using the hand-sorting method and Berlese-Tullgren extraction. The reserve possesses ecosystems of "terra-firme" forest and the trail system represents a gradient of topographic soil factors and vegetation, avoiding categorizations. Considering the abundance and diversity of Pseudoscorpionida, we investigated the relation of the community to environmental factors tested (topography, clay percentage, litter, and soil pH, to the two major drainage basins of the reserve, and if these invertebrates can be used as biological indicators to monitor changes. We registered two species for the first time in the reserve, increasing the known diversity to 17 species. The lack of correlation with the predictor variables and the large home range, indicate that pseudoscorpions are not good biological indicators in the reserve. As the eastern and western watersheds are not separate management units for the community, our results show that they are generalist predators. In spite of our results and lack of knowledge concerning their biology, life history and taxonomy, pseudoscorpions are cosmopolitan and easy to find and measure. Compared with previous studies in the reserve, they have a consistent pattern of abundance and diversity throughout the years showing the stability of the community which can be checked mainly by comparison with environmental changes that would occur in the reserve. An investigation on a medium-spatial scale pattern and over a long-term period including other habitats, and also other predictor variables, like humidity, the structure of the vegetation and canopy closure, will be necessary to reinforce the observed tendencies.

  11. Characterization of the Roraima savanna across of X-ray diffraction, thermomagnetic analysis and Moessbauer spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Gilmar A.; Araujo, R.C.; Sergio, C.S. [Universidade Federal de Roraima (UFRR), Boa Vista, RR (Brazil)

    2012-07-01

    Full text: The technique of X-ray diffraction has great resolving power to determine the phases present in crystalline material, thereby enabling it to determine the elements present in the materials as well as changes in structure that they can suffer when subjected to various physical processes and/or chemical means. The research had as objective to characterize the mineralogy of iron oxides, silicon, aluminum and other minerals in the soil of five points of the Roraima savannah. The points where samples were collected are five municipalities in the state of Roraima. The area of sampling is part of the savanna in Roraima. The samples were collected. We analyzed samples from five points from the collection of natural soil in the locations listed. The samples were placed in a mill to a uniform grain size. After the milling process, the magnetic material was separated using a permanent magnet. Then the samples were analyzed by x-ray diffraction, thermomagnetic analysis and Moessbauer spectroscopy. Preliminary results of XRD showed the occurrence of phases of oxides of iron, silicon, aluminum and other phases less. Thermomagnetic analysis show that the magnetic phases are magnetite and hematite. The results of the Moessbauer spectroscopy indicates the reliability in the two prior art and confirmed the presence of the phases of oxides of iron present in the soil analyzed. (author)

  12. Greenhouse gases study in Amazonia

    International Nuclear Information System (INIS)

    D'Amelio, Monica Tais Siqueira

    2006-01-01

    The Amazon plays an important role on the global carbon cycle, as changing as carbon storage, since Amazon Basin is the biggest area of tropical forest, around 50% of global. Natural's process, deforestation, and use land are CO 2 sources. The Amazon forest is a significant source of N 2 O by soil process, and CH 4 by anaerobic process like flooded areas, rice cultures, and others sources. This project is part of the LBA project (Large-Scale Biosphere Atmosphere Experiment in Amazonia), and this project is 'Vertical profiles of carbon dioxide and other trace gas species over the Amazon basin using small aircraft'. Since December 2000 vertical profiles of CO 2 , CH 4 , CO, H 2 , N 2 O and SF 6 have been measured above central Amazonia. The local sampling was over Tapajos National Forest, a primary forest in Para State, where had a CO 2 flux tower and an east impact area with sources like animals, rice cultivation, biomass burning, etc, to compare the influence of an impact area and a preserved area in the profiles. The Reserva Biologica de Cuieiras, at Amazon State, is the other studied place, where there already exists a CO 2 flux tower, and an east preserved area at this State, to compare with the Cuieiras. The sampling has been carried out on vertical profile from 1000 ft up to 12000 ft using a semi-automated sampling package developed at GMD/NOAA and a small aircraft. The analysis uses the MAGICC system (Multiple Analysis of Gases Influence Climate Change) which is installed at the Atmospheric Chemistry Laboratory (LQA) in IPEN (Instituto de Pesquisas Energeticas e Nucleares). The results showed that all gases studied, except H 2 gas, has been following the global trend. At the Para State, for the studied years, the Amazonian Forest performed as small CO 2 sink. To compare Wet and Dry Seasons, subtracted the Ascension concentration values in the period to remove the global influence. So that, in the 2004 and 2005 wet seasons and 2004 dry season comparison it was

  13. Florística e fitossociologia de uma floresta de vertente na Amazônia Central, Amazonas, Brasil Floristic and phytosociology of a slope forest in Central Amazonia, Amazonas, Brazil

    Directory of Open Access Journals (Sweden)

    Arlem Nascimento de Oliveira

    2004-01-01

    Full Text Available O estudo florístico e fitossociológico de árvores, palmeiras e lianas com diâmetro à altura do peito (DAP >10 cm, em uma floresta de vertente na Amazônia Central (2º35'45" S e 60º12'40" W, foi realizado empregando-se 20 parcelas de 50 x 10 m, distribuídas em dois transectos paralelos de 500 x 10 m. Foram registrados 771 indivíduos, pertencentes a 50 famílias, 120 gêneros e 239 espécies. Das espécies amostradas, 44% são "localmente raras". Sapotaceae, Lecythidaceae, Fabaceae, Caesalpiniaceae e Chrysobalanaceae constituíram as cinco famílias com maior riqueza de espécies e número de indivíduos. Dos 771 indivíduos amostrados, mais de 65% apresentaram DAP > 20 cm. As espécies Eschweilera bracteosa e Protium apiculatum apresentaram os maiores valores de IVI. Cerca de 83% das espécies encontram-se distribuídas aleatoriamente no hectare amostrado. O índice de diversidade Shannon-Wiener foi de 5,01 nats.indivíduo-1, com uniformidade de 0,91, valores altos no contexto de levantamentos semelhantes na região. A heterogeneidade edáfica e topográfica da área, as taxas de recrutamento de novos indivíduos e de espécies "localmente raras" à comunidade local, podem ter contribuído para as altas dissimilaridade (36,2% e diversidade florísticas documentadas neste estudo.The floristic and phytosociological study of trees, palms and lianas with diameter at breast height (DBH >10 cm in a forest slope in Central Amazonia (2º35'45 "S and 60º12'40" W was carried out using 20 plots of 50 x 10 m, distributed in two parallel transects of 500 x 10 m. A total of 771 plants were registered, belonging to 50 families, 120 genera and 239 species. Of the sampled species, 44% are locally rare. Families with the most species and number of individuals were Sapotaceae, Lecythidaceae, Fabaceae, Caesalpiniaceae and Chrysobalanaceae. More than 65% of the sampled plants had DBH > 20 cm. Eschweilera bracteosa and Protium apiculatum were the most

  14. Marine intervals in Neogene fluvial deposits of western Amazonia

    Science.gov (United States)

    Boonstra, Melanie; Troelstra, Simon; Lammertsma, Emmy; Hoorn, Carina

    2014-05-01

    Amazonia is one of the most species rich areas on Earth, but this high diversity is not homogeneous over the entire region. Highest mammal and tree-alpha diversity is found in the fluvio-lacustrine Pebas system, a Neogene wetland associated with rapid radiation of species. The estuarine to marine origin of various modern Amazonian fish, plants, and invertebrates has been associated with past marine ingressions into this freshwater Pebas system. The exact nature and age of these invasions is, however, debated. Here we present new evidence from fluvial and fluvio-lacustrine deposits of Neogene age in southeast Colombia, that point to periods of widespread marine conditions in western Amazonia. Our evidence is based on an analysis of marine palynomorphs, such as organic linings of foraminifera and dinoflagellate cysts, present in dark sandy clay sediments that outcrop along the Caqueta and Amazon rivers. Characteristically, the foraminiferal linings can be assigned to three benthic morphotypes only, e.g. Ammonia, Elphidium and Trochammina. This low diversity assemblage is associated with estuarine/marginal marine conditions. No distinct marine elements such as shelf or planktonic species were encountered. The observed foraminiferal linings and dinocyst assemblages are typical for a (eutrophic) shallow marine environment, suggesting that the Pebas freshwater wetland system occasionally changed to (marginal) marine. Although some reworked elements are found, a typical Neogene dinocyst taxon is commonly found supporting in situ deposition. Sedimentological features typical for tidal conditions that are reported for sites in Peru and northeastern Brazil likely relate to these marine ingressions. Sea level changes as well as foreland basin development related to Andes formation may have facilitated the entry of marine water during the Neogene.

  15. The domestication of Amazonia before European conquest.

    Science.gov (United States)

    Clement, Charles R; Denevan, William M; Heckenberger, Michael J; Junqueira, André Braga; Neves, Eduardo G; Teixeira, Wenceslau G; Woods, William I

    2015-08-07

    During the twentieth century, Amazonia was widely regarded as relatively pristine nature, little impacted by human history. This view remains popular despite mounting evidence of substantial human influence over millennial scales across the region. Here, we review the evidence of an anthropogenic Amazonia in response to claims of sparse populations across broad portions of the region. Amazonia was a major centre of crop domestication, with at least 83 native species containing populations domesticated to some degree. Plant domestication occurs in domesticated landscapes, including highly modified Amazonian dark earths (ADEs) associated with large settled populations and that may cover greater than 0.1% of the region. Populations and food production expanded rapidly within land management systems in the mid-Holocene, and complex societies expanded in resource-rich areas creating domesticated landscapes with profound impacts on local and regional ecology. ADE food production projections support estimates of at least eight million people in 1492. By this time, highly diverse regional systems had developed across Amazonia where subsistence resources were created with plant and landscape domestication, including earthworks. This review argues that the Amazonian anthrome was no less socio-culturally diverse or populous than other tropical forested areas of the world prior to European conquest. © 2015 The Author(s).

  16. Miocene freshwater Mollusca from western Brazilian Amazonia

    NARCIS (Netherlands)

    Wesselingh, F.P.; Ranzi, A.; Räsänen, M.E.

    2006-01-01

    Thirteen species of fossil molluscs are reported from the Solimões Formation of western Brazilian Amazonia. Based on mammalian chronology of the Solimões Formation and radiometric ages reported from coeval deposits in adjacent Peru, the age of the fauna is established as Late Miocene. The fauna

  17. Lizards of Brazilian Amazonia (Reptilia: Squamata)

    NARCIS (Netherlands)

    Avila-Pires, T.C.S.

    1995-01-01

    Eighty-nine species of lizards, six of which polytypic (forming a total of 97 taxa), are presently known from Brazilian Amazonia. This number includes six species and one subspecies described as new to science in this paper: Stenocercus fimbriatus, Lepidoblepharis hoogmoedi, Leposoma osvaldoi, L.

  18. Extractive reserves in Brazilian Amazonia

    Energy Technology Data Exchange (ETDEWEB)

    Fearnside, P.M (National Institute for Research in the Amazon, Manaus-Amazonas (Brazil))

    1989-06-01

    In 1985 an opportunity arose for maintaining tracts of Amazonian forest under sustainable use. Brazil's National Council of Rubber Tappers and the Rural Worker's Union proposed the creation of a set of reserves of a new type, called extractive reserves. The first six are being established in one of the Brazilian states most threatened by deforestatation. The creation of extractive reserves grants legal protection to forest land traditionally used by rubber tappers, Brazil-nut gatherers, and other extractivists. The term extrativismo (extractivism) in Brazil refers to removing nontimber forest products, such as latex, resins, and nuts, without felling the trees. Approximately 30 products are collected for commercial sale. Many more types of forest materials are gathered, for example as food and medicines, for the extractivists' own use. The reserve proposal is attractive for several reasons related to social problems. It allows the rubber tappers to continue their livelihood rather than be expelled by deforestation. However, it is unlikely that sufficient land will be set aside as extractive reserves to employ all the tappers. Displaced rubber tappers already swell the ranks of urban slum dwellers in Brazil's Amazonian cities, and they have become refugees to continue their profession in the forests of neighboring countries, such as Bolivia.

  19. Produtos e subprodutos da medicina popular comercializados na cidade de Boa Vista, Roraima

    OpenAIRE

    PINTO, Angélica Auxiliadora da Costa; MADURO, Cice Batalha

    2003-01-01

    O objetivo deste estudo foi identificar produtos e subprodutos de origem animal e vegetal utilizados na medicina popular que são comercializados na cidade de Boa Vista, Estado de Roraima, traçando um perfil preliminar de sua forma de comercialização. Foram identificados 117 produtos : 100 (85,5 %) de origem vegetal e 17 (14,5 %) de origem animal. Os produtos de origem vegetal de maior destaque foram o Jatobá (Hymenaea courbaril), o Barbatimão (Stryphnodendron adstrinfens), a Sucuba (Himatanth...

  20. Produtos e subprodutos da medicina popular comercializados na cidade de Boa Vista, Roraima

    OpenAIRE

    PINTO,Angélica Auxiliadora da Costa; MADURO,Cice Batalha

    2003-01-01

    O objetivo deste estudo foi identificar produtos e subprodutos de origem animal e vegetal utilizados na medicina popular que são comercializados na cidade de Boa Vista, Estado de Roraima, traçando um perfil preliminar de sua forma de comercialização. Foram identificados 117 produtos : 100 (85,5 %) de origem vegetal e 17 (14,5 %) de origem animal. Os produtos de origem vegetal de maior destaque foram o Jatobá (Hymenaea courbaril), o Barbatimão (Stryphnodendron ads...

  1. Caracterização Química do Óleo Essencial de Philodendron sp. no Município de São João da Baliza, Roraima

    Directory of Open Access Journals (Sweden)

    Nakita Eugene Bacchus

    2015-12-01

    Full Text Available In the Amazon region of Brazil, the roots of different species of Philodendron sp. are used in traditional medicine. This study aims to characterize the chemical composition of the essential oils of Philodendron genus, native in mountain area in the municipality of São João da Baliza, from the Roraima state. The essential oils roots were extracted by hydrodistillation in Clevenger type apparatus for a period of three consecutive hours. The identification of chemical constituents was made by comparison of the mass spectra of the substances with the database of the GCMS system and Kovats index. DOI: http://dx.doi.org/10.17807/orbital.v7i4.774

  2. Man biting rate seasonal variation of malaria vectors in Roraima, Brazil

    Directory of Open Access Journals (Sweden)

    Fábio Saito Monteiro de Barros

    2007-06-01

    Full Text Available Malaria control has been directed towards regional actions where more detailed knowledge of local determinants of transmission is of primary importance. This is a short report on range distribution and biting indices for Anopheles darlingi and An. albitarsis during the dry and rainy season that follows river level variation in a savanna/alluvial forest malaria system area in the Northern Amazon Basin. Distribution range and adult biting indices were at their highest during the rainy season for both An. darlingi and An. albitarsis. During the rainy season the neighboring alluvial forest was extensively flooded. This coincided with highest rates in malaria transmission with case clustering near the river. As the river receded, anopheline distribution range and density decreased. This decrease in distribution and density corresponded to a malaria decrease in the near area. An exponential regression function was derived to permit estimations of An. darlingi distribution over specified distances. Anopheline spatio-temporal variations lead to uneven malaria case distribution and are of important implications for control strategies.

  3. [Identifying areas of epidemiological stratification in an onchocerciasis focus in Yanomami territory, Roraima, Brazil].

    Science.gov (United States)

    Coelho, G E; Vieira, J B; Garcia-Zapata, M T; Schuertz, J C

    1998-01-01

    In this paper, aimed at suitable planning, analysis, and follow-up of treatment, control, and eradication in a human onchocerciasis program, were studied 27 geographic areas and examined 3,974 inhabitants. Four epidemiological areas with different prevalences were identified and stratified.

  4. Report control Chrysomelids in the experimental field of camu-camu from Embrapa Roraima-Brazil

    Directory of Open Access Journals (Sweden)

    Carlos Abanto Rodriguez

    2013-12-01

    Full Text Available Camu-camu is a native fruit tree of the Amazon, is highly value nutritious and great economic potential due to the high content of ascorbic acid (6112 mg/100 g present in fruits. Camu-camu, like any other plant, when it becomes cultivated outside their natural environment, loses its ecological balance and, consequently, is attacked by phytophagous and severe insect pests, which cause serious damage to the orchard. In this sense, the aim with this study, reporting the identification and control of insect pests in the cultivation of camu-camu, using different methods to attract and capture. It was observed that the best results were obtained in applying Neenmax®, followed by traps shading of black color screen, furthermore, higher occurrence of insects were recorded belonging to the family Chrysomelidae.

  5. Análise econômica de sistemas agroflorestais na Amazônia ocidental, Machadinho d'Oeste- RO Economic analysis of agroforestry systems in eastern Amazonia, Machadinho d'Oeste- RO, Brazil

    Directory of Open Access Journals (Sweden)

    Michelliny de Matos Bentes-Gama

    2005-06-01

    tested, T1 Brazil nut-Banana-Black pepper-Cupuaçu was the agroforestry system (AFS with the best financial results, comparing to T2 Frreijó wood- banana-black pepper-cupuaçu and T3 Pupunha palm- banana-black pepper-cupuaçu. The management and harvesting costs represented more than 70% of the total cost composition; and the labor cost participation was higher than 50% in the site preparation and long-term maintenance phases of the agroforestry systems. The risk analysis simulation showed that the variables which affected Infinite Horizon Net Present Value (NPV*, according to the ranking of importance (R, were: discount rate, price of cupuaçu fruits (Theobroma grandiflorum, harvesting cost, price of Brazil nut (Bertholletia excelsa wood, and long-term maintenance costs. Even though the high establishment and the long-term maintenance costs, AFS T1 Castanha-do-brasil-Banana-black pepper-cupuaçu showed a 15% probability that Net Present Value (NPV value could be concentrated around R$ 35.000 ha-1 year-1.

  6. EXPRESSÕES ORAIS POPULARES UTILIZADAS PELO POVO DO LAVRADO EM RORAIMA

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    Sebastião Pereira Nascimento

    2016-08-01

    Full Text Available São apresentadas 564 expressões orais populares utilizadas pelos habitantes do lavrado em Roraima. A maioria dos significados dos termos é originária da herança cultural trazida pelo povo nordestino radicado nos Campos do Rio Branco desde o século XIX. As línguas indígenas também têm influência nestas expressões orais locais, com destaque para as famílias linguísticas Karib e Aruak. Alguns termos têm influências culturais de outras regiões brasileiras e fragmentos de línguas estrangeiras.

  7. Andean settlers rush for Amazonia.

    Science.gov (United States)

    Serra-vega, J

    1990-01-01

    Governments of Andean countries (Peru, Bolivia, Colombia, Ecuador, and Venezuela) have encouraged migration to the Amazon Basin, which has contributed to its destruction. Population pressure, landlessness, and poverty are the inducements to migrate. Efforts to populate the Amazon forest were begun as early as 1964 in Peru without international notice. By 1980, logging was allowed in Peru, and Brazil considered colonization of the Amazon essential to national sovereignty. By 1986, outside of Lima, Peru, a development project originally funded by the World Bank, the InterAmerican Development Bank, and the US, resulted in conflicts between settlers and Indians, in loggers indiscriminately cutting, and in farmers using slash and burn techniques to clear forests. Elsewhere the Peruvian Amazon, in San Ignacio, the population was growing by 5.5%/year. The jungle road that had been started but never completed, Carretera Marginal, destroyed 5 million hectares of primary forest, and much of the 600,000 hectares of arable land gained by the road suffered from inappropriate farming practices which caused massive erosion and laterization of the soils. Food crop production declined, and production of coca for cocaine increased. Coca crops are controlled by the Shining Path guerrillas, who are trying to overthrow the Peruvian government. Devastation of Ecuador around Lago Agrio continues. In Colombia, east of Bogota, forests have disappeared and hills have eroded and silted up rivers and dams. The Andean piedmont in Bolivia has also been devastated by loggers and by slash and burn farming. Southeastern Bolivian forests have been cleared for soya bean cultivation on poor soils. Social and economic crises propel people into the remaining forests. The solution is to ease foreign debt, transfer appropriate technology at affordable prices, refuse to finance destructive development, and help to educate and train scientific researchers. Family planning services are also urgently needed

  8. Resposta do feijão-caupi as lâminas de irrigação e as doses de fósforo no cerrado de Roraima Response of cowpea to water levels and phosphate fertilizer on the savanna of Roraima

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    Gabriela Almeida Oliveira

    2011-12-01

    Full Text Available O objetivo do trabalho foi estudar o comportamento do feijão-caupi (Vigna ungüiculata (L. Walp. cv. BRS Novaera sob quatro lâminas de água (273; 257; 241 e 187 mm e doses de fósforo (0; 70; 140; 210 kg ha-1 de P2O5, aplicados na forma de superfosfato triplo, em Boa Vista, Roraima. O delineamento experimental adotado foi o de blocos ao acaso, no esquema de parcelas subdivididas com quatro repetições. As parcelas foram constituídas pelas lâminas de água e as sub parcelas pelas doses de fósforo, resultando em 16 tratamentos. A irrigação foi realizada por um sistema convencional de aspersão, montado no campo segundo o sistema de "aspersão em linha". As massas seca da parte aérea e de 100 grãos foram influenciadas significativamente pela interação entre lâminas de água e doses de fósforo, enquanto o número de grãos por vagem e o comprimento da vagem foram influenciados somente pelas doses de fósforo. A dose de máxima eficiência econômica foi de 89,45 kg de P2O5, com produtividade de 1.306 kg ha-1.This work was carried out to evaluate the effect of irrigation depth and phosphate fertilizer (0; 70; 140; 210 kg ha-1 de P2O5 on yield and production components of cowpea (Vigna unguiculata L. Walp cv. Novaera at the Savanna of Roraima, Brazil. The experimental design was arranged in a completely randomized block in split-plot and four replications. Irrigation depths were applied through a sprinkler line source system. The principal treatments constituted on the depths of irrigation and the secondary treatments by the phosphate fertilizer. Significant effects (p < 0.05 of the depth of irrigation and phosphate fertilizer interaction with aerial mass production and mass of 100 grains were observed. The number of grains per pods and size of pod were affected by the phosphate fertilizer only. The highest economical yield (1,306 kg ha-1 was obtained by 89.45 kg of P2O5.

  9. Caracterização de isolados de Rhizoctonia associados à queima foliar em Roraima = Characterization of Rhizoctonia isolates associated with foliar blight in Roraima.

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    Dayane Rodrigues Youssef

    2012-08-01

    Full Text Available O objetivo desse trabalho foi caracterizar isolados do fungo Rhizoctonia associados à queima foliar, obtidos de hospedeiros de importância econômica no estado de Roraima. Os isolados foram obtidos de plantas de feijão-caupi (Vigna unguiculata, soja (Glycine max, seringueira (Hevea brasiliensis, melancia (Citrullus lanatus, alface (Lactuca sativa e feijão-guandu (Cajanus cajan. Os parâmetros utilizados foram números de núcleos, grupo de anastomose e as características culturais da colônia, taxa de crescimento micelial e a formação de escleródios nos meios de cultura: batata dextrose agar (BDA, BDA+asparagina, BDA+extrato de levedura, Czapek Agar, maltose-peptona-agar, soil extract agar, sacarose-yeast-asparagina e V-8. Todos os 10 isolados estudados foram caracterizados como multinucleados e pertencentes à espécie Rhizoctonia solani. Três isolados de feijão-caupi, um de soja e o isolado de melancia foram identificados como AGI-1A e um isolado de feijãocaupi, um de soja e o isolado de feijão-guandu como AGI-1B. O isolado de seringueira não foi identificado como nenhum dos padrões de anastomose utilizado. Para a maioria dos isolados as maiores taxas de crescimento micelialforam obtidas no meio de cultura Soil Extract Agar. Dois tipos de escleródios, característicos do grupo AGI, foram observados: formação de 2-20 tufos placa-1 coloração variável, 1-2 mm e formação de 38-611 microescleródios placa-1, de coloração marrom, medindo 100 μm. A produção e o tipo de escleródio variaram com o isolado e o meio de cultura utilizado.The aim of this work was to characterize Rhizoctonia isolates associated with foliar blight symptom from hosts with economic importance at Roraima state. The isolates were recovered from cowpea (Vigna unguiculata, soybean (Glycine max, rubber tree (Hevea brasiliensis, watermelon (Citrullus lanatus, lettuce (Lactuca sativa and pigeonpea (Cajanus cajan. The evaluated characteristics were nuclear

  10. [The Brazilian focus of onchocerciasis: new observations in the areas of the Mucajaí and Catrimâni rivers, Territory of Roraima].

    Science.gov (United States)

    Moraes, M A; Shelley, A J; Luna Dias, A P

    1986-01-01

    A recent survey for onchocerciasis conducted among the Yanomami Indians living on the middle reaches of the Mucajaí and Catrimâni Rivers (Territory of Roraima) has failed to show any alteration in the local pattern of the disease. In fact, after a decade from the first surveys in these areas located at the periphery of the Yanomami focus, the prevalence and the intensity of infection have not experienced a significant change. Considering only the residents in the villages inside the surveyed areas, the prevalence varied from zero in the neighbourhood of the Catrimâni mission to 3.1 per cent near the Mucajaí mission. Had there been a competent vector of Onchocerca volvulus in the region higher rates might be expected due to the Yanomami custom of periodic visits among the groups of the tribe. In some of these visits, numbers of highly infected Indians from the central and mountainous part of the Yanomami territory--where more than 90 per cent of the adults have onchocerciasis--come to the villages in the lowland area, attracted by the facilities offered by the mission posts. As the visitors stay in the host villages for several days or weeks, the residents could become exposed to the disease. Simulium oyapockense s.1., a man-biting species of black fly, widely distributed in Northern Brazil, is the only possible vector of O. volvulus in the investigated areas, on the grounds of its local abundance.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Neogene climate evolution in Amazonia and the Brazilian Northeast

    NARCIS (Netherlands)

    Hoorn, C.; Bernardes-de-Oliveira, M.E.C.; Dino, R.; Garcia, M.J.; Antonioli, L.; da Costa Casado, F.; Hooghiemstra, H.; de Souza Carvalho, I.; Garcia, M.J.; Strohschoen, O.; Cunha Lana, C.

    2014-01-01

    Climate change follows from the interaction between global atmospheric and oceanic processes with regional processes. In this chapter we review which factors determined climate evolution in Amazonia and the Brazilian Northeast and present a recompilation of Neogene palynological and paleobotanical

  12. Sources of water vapor to economically relevant regions in Amazonia and the effect of deforestation

    Science.gov (United States)

    Pires, G. F.; Fontes, V. C.

    2017-12-01

    The Amazon rain forest helps regulate the regional humid climate. Understanding the effects of Amazon deforestation is important to preserve not only the climate, but also economic activities that depend on it, in particular, agricultural productivity and hydropower generation. This study calculates the source of water vapor contributing to the precipitation on economically relevant regions in Amazonia according to different scenarios of deforestation. These regions include the state of Mato Grosso, which produces about 9% of the global soybean production, and the basins of the Xingu and Madeira, with infrastructure under construction that will be capable to generate 20% of the electrical energy produced in Brazil. The results show that changes in rainfall after deforestation are stronger in regions nearest to the ocean and indicate the importance of the continental water vapor source to the precipitation over southern Amazonia. In the two more continental regions (Madeira and Mato Grosso), decreases in the source of water vapor in one region were offset by increases in contributions from other continental regions, whereas in the Xingu basin, which is closer to the ocean, this mechanism did not occur. As a conclusion, the geographic location of the region is an important determinant of the resiliency of the regional climate to deforestation-induced regional climate change. The more continental the geographic location, the less climate changes after deforestation.

  13. Geostationary satellite estimation of biomass burning in Amazonia during BASE-A

    International Nuclear Information System (INIS)

    Menzel, W.P.; Cutrim, E.C.; Prins, E.M.

    1991-01-01

    This chapter presents the results of using Geostationary Operational Environmental Satellite (GOES) Visible Infrared Spin Scan Radiometer Atmospheric Sounder (VAS) infrared window (3.9 and 11.2 microns) data to monitor biomass burning several times per day in Amazonia. The technique of Matson and Dozier using two window channels was adapted to GOES VAS infrared data to estimate the size and temperature of fires associated with deforestation in the vicinity of Alta Floresta, Brazil, during the Biomass Burning Airborne and Spaceborne Experiment - Amazonia (BASE-A). Although VAS data do not offer the spatial resolution available with AVHRR data 97 km versus 1 km, respectively, this decreased resolution does not seem to hinder the ability of the VAS instrument to detect fires; in some cases it proves to be advantageous in that saturation does not occur as often. VAS visible data are additionally helpful in verifying that the hot spots sensed in the infrared are actually related to fires. Furthermore, the fire plumes can be tracked in time to determine their motion and extent. In this way, the GOES satellite offers a unique ability to monitor diurnal variations in fire activity and transport of related aerosols

  14. Outstanding insecurities concerning the use of an Ov16-based ELISA in the Amazonia onchocerciasis focus

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    Sérgio Luiz Bessa Luz

    2014-07-01

    Full Text Available In a recent issue of Memórias do Instituto Oswaldo Cruz, published in Rio de Janeiro in February 2014 (109: 87-92, Adami et al. have published a survey reporting Mansonella parasite prevalence in the Amazon Region. This report makes a useful contribution to the existing knowledge of filarial parasite distribution within the Amazon area, parasite prevalence rates in relation to age and occupation and provides observations on the possible clinical impact of Mansonella ozzardi. Their publication also provides an account of what appears to be a novel ELISA that has recently been used in the Simuliidae and Onchocerciasis Laboratory of the Oswaldo Cruz Institute, Rio de Janeiro, Brazil. We are concerned that the publication of this ELISA may have created an excessively positive impression of the effectiveness of the onchocerciasis recrudescence serological surveillance tools that are presently available for use in the Amazonia onchocerciasis focus. In this letter we have, thus, sought to highlight some of the limitations of this ELISA and suggest how continuing insecurities concerning the detection of antibodies to Onchocerca volvulus within the Amazonia onchocerciasis focus might be minimised.

  15. Pre-Columbian Earthworks in Coastal Amazonia

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    Stéphen Rostain

    2010-03-01

    Full Text Available As in other parts of Amazonia, pre-Columbian Indians have profoundly modified the coast of the Guianas. Between 650 and 1650 AD, Arauquinoid people occupied a territory that was approximately 600 km long and used the raised field technique intensively before the European conquest. They erected thousands of raised fields of various shapes, dug canals, ditches, and pathways, and built artificial mounds to establish their villages. All these earthworks changed forever the face of the coastal flooded savannas and their ecology. Such labor was probably organized under the leadership of a central authority: it seems that Arauquinoid societies were organized in a chiefdom system. Statistical calculations, based on the known surface area of raised fields and on their estimated productivity, suggest a population density of 50 to 100 inhabitants per km2. Pre-Columbian inhabitants of the Guianas coast carefully organized, managed and “anthropisized” their territory following a specific pattern.

  16. Within-canopy sesquiterpene ozonolysis in Amazonia

    Science.gov (United States)

    Jardine, K.; YañEz Serrano, A.; Arneth, A.; Abrell, L.; Jardine, A.; van Haren, J.; Artaxo, P.; Rizzo, L. V.; Ishida, F. Y.; Karl, T.; Kesselmeier, J.; Saleska, S.; Huxman, T.

    2011-10-01

    Through rapid reactions with ozone, which can initiate the formation of secondary organic aerosols, the emission of sesquiterpenes from vegetation in Amazonia may have significant impacts on tropospheric chemistry and climate. Little is known, however, about sesquiterpene emissions, transport, and chemistry within plant canopies owing to analytical difficulties stemming from very low ambient concentrations, high reactivities, and sampling losses. Here, we present ambient sesquiterpene concentration measurements obtained during the 2010 dry season within and above a primary tropical forest canopy in Amazonia. We show that by peaking at night instead of during the day, and near the ground instead of within the canopy, sesquiterpene concentrations followed a pattern different from that of monoterpenes, suggesting that unlike monoterpene emissions, which are mainly light dependent, sesquiterpene emissions are mainly temperature dependent. In addition, we observed that sesquiterpene concentrations were inversely related with ozone (with respect to time of day and vertical concentration), suggesting that ambient concentrations are highly sensitive to ozone. These conclusions are supported by experiments in a tropical rain forest mesocosm, where little atmospheric oxidation occurs and sesquiterpene and monoterpene concentrations followed similar diurnal patterns. We estimate that the daytime dry season ozone flux of -0.6 to -1.5 nmol m-2 s-1 due to in-canopy sesquiterpene reactivity could account for 7%-28% of the net ozone flux. Our study provides experimental evidence that a large fraction of total plant sesquiterpene emissions (46%-61% by mass) undergo within-canopy ozonolysis, which may benefit plants by reducing ozone uptake and its associated oxidative damage.

  17. Etnopedologia e transferência de conhecimento: diálogos entre os saberes indígena e técnico na Terra Indígena Malacacheta, Roraima Ethnopedology and knowledge transfer: dialogue between indians and soil scientists in the Malacacheta Indian Territory, Roraima, Amazon

    Directory of Open Access Journals (Sweden)

    José Frutuoso do Vale Jr.

    2007-04-01

    benéficas: facilitou a transferência de conhecimento entre dois saberes, in loco, desvendando boa parte das relações etnopedológicas e etnoecológicas e refletindo sobre "como" e "por que" cada grupo identificava um dado tipo de solo. Permitiu ainda delinear o esboço da distribuição dos solos com base no saber indígena, utilizando a extrapolação cartográfica disponível ao pedólogo; esse fato facilitou o próprio mapeamento convencional, especialmente no reconhecimento de inclusões e associações de solos. De forma mais destacada, a experiência permitiu ainda uma real comunicação e aproximação entre os agentes do saber (indígenas e técnico, com base na troca e em descobertas mútuas de conhecimentos, gerando uma sinergia que aproxima o técnico e o indígena, com resultados práticos palpáveis, que extrapolam o próprio objetivo inicial do levantamento de solos da TI Malacacheta.Ethnopedology deals mainly with indigenous knowledge on pedo-diversity. In this sense, the agricultural and cultural traditions of the Wapishana Indians in Roraima, of the Arawak linguistic background, constitute a relevant pool of ethno-scientific knowledge in Amazonia. The Federal University of Roraima has increasingly acknowledged their importance in the Indigenous Education undergraduate courses. In this study, the ethnopedological classifications of the Wapishana Indians were confronted with the Brazilian System of Soil Classification in a soil survey of the Malacacheta Indian Territory. The ethnopedological classification of Wapishana Indians identifies and separates all environmental segments of the area, relating easily recognizable aspects of the soilscape (color, texture, depth, vegetation with observable aspects (land use, cultivation type, suitability. The Wapishana classify eight basic soil types, that occur either separately or in associations: Imii Wyzda'u (Yellowish earth, Imii Wyza'u (Red earth, Imii Pudiidiu (Black Earth, Imii Pudiidiza'u (Dusky

  18. PREDICTION OF CHEMICAL AND PHYSICAL PROPERTIES OF RORAIMA SOILS BY NEAR INFRARED SPECTROSCOPY

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    Edmilson E. Silva

    2017-06-01

    Full Text Available Soils testing are time consuming and costly to operate, and can generate as high toxicity residues for the people or environment. Near Infrared Spectroscopy is one good alternative to replace conventional techniques, because it is fast – 60 seconds by sample, without producing residues and applicable to all soil properties, like physics and chemical properties. The objective of this study was to evaluate the NIR technique in quantifying various Roraima soil properties. Eighty-four soil samples collected in XI RCC soil profiles were analyzed for K and Na available, organic carbon, total nitrogen, Si, Fe and Al oxides and sand and clay contents by conventional and NIR techniques. NIR spectra were obtained in the range of 10000 cm-1 to 4000 cm-1, with spectral resolution of 4 cm-1. With the all bands were adjusted by calibration and validation models submitted to pre-treatments with the purpose of reducing the noise effect and the absence of linearity. Except in relation to the available K, calibration models had R2 values for calibration and validation above 80% for all other soil properties tested. It is concluded that the NIR technique had good predictive capacity of the soil properties tested, and can be used for any variable whose interpretation is obtained based on continuous value intervals. Keywords: soil testing; green chemistry; Amazon.

  19. STRUCTURE, SPATIAL DISTRIBUTION AND SEED YIELD FOR ANDIROBA (Carapa guianensis Aubl. IN SOUTH RORAIMA

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    Ademir R. Ruschel

    2009-09-01

    Full Text Available Andiroba is one of the Amazon species with great potential of exploration for timber and non-timberforest products (NFTPs. This work was carried out with the objective of studying the population structure,spatial distribution and seed yield in a native forest of andiroba in the south of Roraima state. A permanentsample plot of 300 x 300 m (9 ha was installed and all the trees with DBH equal or superior to 10 cm wereidentified, mapped and measured. In each tree, the light climate, crown form and lianas load were appraised.To identify the spatial distribution, the medium variance/average rate and the Morisita’s Index were used.The seed yield data were obtained by the seed weighing, being 145 trees monitored during 2006. Thepopulation presented a diametric distribution of the j inverted type, and a seed yield of 65,4 kg.ha-1 withaverage of 8,3 kg.tree-1 was observed. DBH ≥ 30 cm was considered as borderline for commercial seed yield,allowing stratifying the population in juveniles (DBH ≤ 30 cm and adults (DBH > 30 cm. The spatialdistribution analysis showed that adult individuals presented random distribution and the juveniles tendencyof grouping.

  20. STRUCTURE, SPATIAL DISTRIBUTION AND SEED YIELD FOR ANDIROBA (Carapa guianensis Aubl. IN SOUTH RORAIMA

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    Helio Tonini

    2009-10-01

    Full Text Available Andiroba is one of the Amazon species with great potential of exploration for timber and non-timber forest products (NFTPs. This work was carried out with the objective of studying the population structure, spatial distribution and seed yield in a native forest of andiroba in the south of Roraima state. A permanent sample plot of 300 x 300 m (9 ha was installed and all the trees with DBH equal or superior to 10 cm were identified, mapped and measured. In each tree, the light climate, crown form and lianas load were appraised. To identify the spatial distribution, the medium variance/average rate and the Morisita’s Index were used. The seed yield data were obtained by the seed weighing, being 145 trees monitored during 2006. The population presented a diametric distribution of the j inverted type, and a seed yield of 65,4 kg.ha-1 with average of 8,3 kg.tree-1 was observed. DBH ≥ 30 cm was considered as borderline for commercial seed yield, allowing stratifying the population in juveniles (DBH ≤ 30 cm and adults (DBH > 30 cm. The spatial distribution analysis showed that adult individuals presented random distribution and the juveniles tendency of grouping.

  1. Uniformidade de sementes de genótipos de feijão-caupi cultivados em dois ambientes no Estado de Roraima. = Seeds uniformity from cowpea genotypes cultivated in two environments of the State of Roraima.

    Directory of Open Access Journals (Sweden)

    Katherine Rodrigues Arruda

    2009-06-01

    Full Text Available - Objetivou-se com o presente trabalho avaliar a uniformidade de sementes de 19 genótipos de feijão-caupi cultivados em dois ambientes no Estado de Roraima. Foram utilizadas sementes produzidas nos Campos Experimentais Serra da Prata (CESP e do Monte Cristo (CEMC pertencentes a Embrapa Roraima, produzidas durante o ano de 2008. Amostras de 400 g de sementes de feijão-caupi foram separadas e pesadas. Após a pesagem, cada amostra foi classifi cada por cinco peneiras de crivos redondos e oblongos de diferentes dimensões. As sementes retidas em cada peneira foram pesadas separadamente. Sementes da maior porção foram avaliadas quanto a massa de mil sementes e germinação. Na análise dos resultados de uniformidade verificou-se que 89,5% das sementes produzidas no CEMC são maiores que 4,5 x 22 mm e no CESP 90,0%. Quanto a massa média de mil sementes não se verifica diferenças entre os dois ambientes, e entre os materiais variação de 127,5 a 219,6 g. As sementes do CESP apresentam qualidade fisiológica superior as do CEMC. = The objective of this study was to evaluated the uniformity of seeds from 19 cowpea genotypes in two environment of Roraima State. The seeds utilized were produced in the experimental fields of Serra da Prata (CESP and Monte Cristo (CEMC, belonging to Embrapa Roraima. Samples of 400 g of cowpea seeds were separated and weighed and classified by five sieves with round and oblong holes of different dimensions, being weighed separately. Seeds retained in each sieve were weighed separately. Seeds withheld in 4.5 x 22 mm sieve were assessed according to mass of a thousand seeds and germination. Results showed that 89.5 % of seeds produced in CEMC are bigger than 4.5 x 22 mm and in CESP 9 0.0%. Concerning to average mass of a thousand seeds, no differences were verified between the two environments, while materials ranged from 127.5 to 219.6 g. Seeds of CESP showed physiological quality superior than CEMC.

  2. On the Relationship of Rainfall and Temperature across Amazonia

    Science.gov (United States)

    Ribeiro Lima, C. H.; AghaKouchak, A.

    2017-12-01

    Extreme droughts in Amazonia seem to become more frequent and have been associated with local and global impacts on society and the ecosystem. The understanding of the dynamics and causes of Amazonia droughts have attracted some attention in the last years and pose several challenges for the scientific community. For instance, in previous work we have identified, based on empirical data, a compounding effect during Amazonia droughts: periods of low rainfall are always associated with positive anomalies of near surface air temperature. This inverse relationship of temperature and rainfall appears at multiple time scales and its intensity varies across Amazonia. To our knowledge, these findings have not been properly addressed in the literature, being not clear whether there is a causal relationship between these two variables, and in this case, which one leads the other one, or they are just responding to the same causal factor. Here we investigate the hypothesis that high temperatures during drought periods are a major response to an increase in the shortwave radiation (due to the lack of clouds) not compensating by an expected increase in the evapotranspiration from the rainforest. Our empirical analysis is based on observed series of daily temperature and rainfall over the Brazilian Amazonia and reanalysis data of cloud cover, outgoing longwave radiation (OLR) and moisture fluxes. The ability of Global Circulation Models (GCMs) to reproduce such compounding effect is also investigated for the historical period and for future RCP scenarios of global climate change. Preliminary results show that this is a plausible hypothesis, despite the complexity of land-atmosphere processes of mass and energy fluxes in Amazonia. This work is a step forward in better understanding the compounding effects of rainfall and temperature on Amazonia droughts, and what changes one might expect in a future warming climate.

  3. Deforestation and Forest Fires in Roraima and Their Relationship with Phytoclimatic Regions in the Northern Brazilian Amazon

    Science.gov (United States)

    Barni, Paulo Eduardo; Pereira, Vaneza Barreto; Manzi, Antonio Ocimar; Barbosa, Reinaldo Imbrozio

    2015-05-01

    Deforestation and forest fires in the Brazilian Amazon are a regional-scale anthropogenic process related to biomass burning, which has a direct impact on global warming due to greenhouse gas emissions. Containment of this process requires characterizing its spatial distribution and that of the environmental factors related to its occurrence. The aim of this study is to investigate the spatial and temporal distribution of deforested areas and forest fires in the State of Roraima from 2000 to 2010. We mapped deforested areas and forest fires using Landsat images and associated their occurrence with two phytoclimatic zones: zone with savanna influence (ZIS), and zone without savanna influence (ZOS). Total deforested area during the interval was estimated at 3.06 × 103 km2 (ZIS = 55 %; ZOS = 45 %) while total area affected by forest fires was estimated at 3.02 × 103 km2 (ZIS = 97.7 %; ZOS = 2.3 %). Magnitude of deforestation in Roraima was not related to the phytoclimatic zones, but small deforested areas (≤17.9 ha) predominated in ZOS while larger deforestation classes (>17.9 ha) predominated in ZIS, which is an area with a longer history of human activities. The largest occurrence of forest fires was observed in the ZIS in years with El Niño events. Our analysis indicates that the areas most affected by forest fires in Roraima during 2000-2010 were associated with strong climatic events and the occurrence these fires was amplified in ZIS, a sensitive phytoclimatic zone with a higher risk of anthropogenic fires given its drier climate and open forest structure.

  4. Deforestation and forest fires in Roraima and their relationship with phytoclimatic regions in the northern Brazilian Amazon.

    Science.gov (United States)

    Barni, Paulo Eduardo; Pereira, Vaneza Barreto; Manzi, Antonio Ocimar; Barbosa, Reinaldo Imbrozio

    2015-05-01

    Deforestation and forest fires in the Brazilian Amazon are a regional-scale anthropogenic process related to biomass burning, which has a direct impact on global warming due to greenhouse gas emissions. Containment of this process requires characterizing its spatial distribution and that of the environmental factors related to its occurrence. The aim of this study is to investigate the spatial and temporal distribution of deforested areas and forest fires in the State of Roraima from 2000 to 2010. We mapped deforested areas and forest fires using Landsat images and associated their occurrence with two phytoclimatic zones: zone with savanna influence (ZIS), and zone without savanna influence (ZOS). Total deforested area during the interval was estimated at 3.06 × 10(3) km(2) (ZIS = 55 %; ZOS = 45 %) while total area affected by forest fires was estimated at 3.02 × 10(3) km(2) (ZIS = 97.7 %; ZOS = 2.3 %). Magnitude of deforestation in Roraima was not related to the phytoclimatic zones, but small deforested areas (≤17.9 ha) predominated in ZOS while larger deforestation classes (>17.9 ha) predominated in ZIS, which is an area with a longer history of human activities. The largest occurrence of forest fires was observed in the ZIS in years with El Niño events. Our analysis indicates that the areas most affected by forest fires in Roraima during 2000-2010 were associated with strong climatic events and the occurrence these fires was amplified in ZIS, a sensitive phytoclimatic zone with a higher risk of anthropogenic fires given its drier climate and open forest structure.

  5. Occurrence of filamentous fungi in Simulium goeldii Cerqueira & Nunes de Mello (diptera: simuliidae larvae in central Amazonia, Brazil Ocorrência de fungos filamentosos associados a larvas de Simulium goeldii Cerqueira & Nunes de Mello da Amazônia Central, Brasil

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    Quézia Ribeiro Fonseca

    2008-06-01

    Full Text Available The family Simuliidae is the host of simbiontes fungi that inhabit the digestive tracts of arthropods. This paper reports the presence of fungi in Simulium goeldii Cerqueira & Nunes de Mello larvae in Amazonia. We observed that the larvae are a good component of aquatic systems to isolate filamentous fungi.A família Simuliidae é hospedeira de fungos simbiontes que habitam o trato digestivo de artrópodos. Este estudo reporta a presença de fungos em larvas de Simulium goeldii Cerqueira & Nunes de Mello da Amazônia. Foi observado que as larvas são bons componentes do sistema aquático para isolar fungos filamentosos.

  6. Biogeochemistry and ecology of terrestrial ecosystems of Amazonia

    Science.gov (United States)

    Malhi, Yadvinder; Davidson, Eric A.

    The last decade of research associated with the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) has led to substantial advances in our understanding of the biogeochemistry and ecology of Amazonian forests and savannas, in particular in relation to the carbon cycle of Amazonia. In this chapter, we present a synthesis of results and ideas that are presented in more detail in subsequent chapters, drawing together evidence from studies of forest ecology, ecophysiology, trace gas fluxes and atmospheric flux towers, large-scale rainfall manipulation experiments and soil surveys, satellite remote sensing, and quantification of carbon and nutrient stocks and flows. The studies have demonstrated the variability of the functioning and biogeochemistry of Amazonian forests at a range of spatial and temporal scales, and they provide clues as to how Amazonia will respond to ongoing direct pressure and global atmospheric change. We conclude by highlighting key questions for the next decade of research to address.

  7. Catalogue of distribution of lizards (Reptilia: Squamata) from the Brazilian Amazonia. IV. Alopoglossidae, Gymnophthalmidae.

    Science.gov (United States)

    Ribeiro-Júnior, Marco A; Amaral, Silvana

    2017-05-22

    We present distribution data of all Alopoglossidae and Gymnophthalmidae lizards known from the Brazilian Amazonia, totaling 54 species-level taxa, belonging to 17 genera and two families. This represents 22 more species-level taxa than previously reported. Data were based on 17,431 specimens deposited in three North American and eight Brazilian museums, including the main collections harboring Amazonian material. Most species (~80%) are endemic to Amazonia; non-endemic species are mainly associated with open vegetation (savanna) enclaves or open dry (semideciduous) forest in Amazonia, with a few exceptions. As a whole, seven taxa (including one species complex) are widespread in Amazonia, six are restricted to eastern Amazonia, seven to western Amazonia, two to southwestern Amazonia, 11 to southern Amazonia, 11 to northern Amazonia (either in part of it or widespread in the Guiana region), and six to the southern peripheral portion of Amazonia. Besides, four species present unique distributions. Considering this study and the other three catalogues of distribution of lizards already published, the total number of lizard species from Brazilian Amazonia increased from 97 to 142 species-level tava. It represents an increase of 45 species from the region since the last revision.

  8. Dynamics, patterns and causes of fires in Northwestern Amazonia.

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    Armenteras, Dolors; Retana, Javier

    2012-01-01

    According to recent studies, two widespread droughts occurred in the Amazon basin, one during 2005 and one during 2010. The drought increased the prevalence of climate-driven fires over most of the basin. Given the importance of human-atmosphere-vegetation interactions in tropical rainforests, these events have generated concerns over the vulnerability of this area to climate change. This paper focuses on one of the wettest areas of the basin, Northwestern Amazonia, where the interactions between the climate and fires are much weaker and where little is known about the anthropogenic drivers of fires. We have assessed the response of fires to climate over a ten-year period, and analysed the socio-economic and demographic determinants of fire occurrence. The patterns of fires and climate and their linkages in Northwestern Amazonia differ from the enhanced fire response to climate variation observed in the rest of Amazonia. The highest number of recorded fires in Northwestern Amazonia occurred in 2004 and 2007, and this did not coincide with the periods of extreme drought experienced in Amazonia in 2005 and 2010. Rather, during those years, Northwestern Amazonia experienced a relatively small numbers of fire hotspots. We have shown that fire occurrence correlated well with deforestation and was determined by anthropogenic drivers, mainly small-scale agriculture, cattle ranching (i.e., pastures) and active agricultural frontiers (including illegal crops). Thus, the particular climatic conditions for air convergence and rainfall created by proximity to the Andes, coupled with the presence of one of the most active colonisation fronts in the region, make this region differently affected by the general drought-induced fire patterns experienced by the rest of the Amazon. Moreover, the results suggest that, even in this wet region, humans are able to modify the frequency of fires and impact these historically well preserved forests.

  9. Flutuação Populacional de Rhynchophorus palmarum L. (Coleoptera: Curculionidae em Plantios de Palma de Óleo em Roraima

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    2015-08-01

    Full Text Available Esta pesquisa teve como objetivo avaliar a flutuação populacional de Rhynchophorus palmarum L. (Coleoptera: Curculionidae em plantios de Elaeis guineensis Jacq, em ecossistemas de savana e floresta no estado de Roraima. A pesquisa foi desenvolvida durante o período de janeiro de 2011 a fevereiro de 2012 nos campos experimentais da Embrapa Roraima: Monte Cristo e Caroebe, numa área de 2 hectares com a cultura da Palma de Óleo, em cada campo. Foram distribuídas armadilhas iscadas com roletes de cana-de-açúcar e feromônio de agregação para captura dos insetos no entorno dos plantios. Ocorreu flutuação de R. palmarum com picos populacionais nos meses de julho e agosto no ecossistema de savana e de abril a setembro no ambiente de floresta. A população de R. palmarum foi menor em meses de baixa precipitação pluviométrica nos dois ambientes avaliados com a Palma de Óleo em Roraima Population Fluctuation of Rhynchophorus palmarum L. (Coleoptera: Curculionidae in Plantations of Oil Palm in Roraima Abstract. This research aimed to evaluate the population fluctuation Rhynchophorus palmarum L. (Coleoptera: Curculionidae in Elaeis guineensis Jacq plantations in forest and savanna ecosystems in the state of Roraima. The research was conducted during the period from January 2011 to February 2012 in the experimental field of Embrapa Roraima: Monte Cristo and Caroebe in an area of 2 hectares with culture Oil Palm in each field. Traps baited with rollers cane sugar and aggregation pheromone for capturing insects in the vicinity of the plantations were distributed. Fluctuation occurred R. palmarum with population peaks in the months of July and August in the savanna ecosystem and from April to September in the forest environment. The population of R. palmarum was lower in months of low rainfall in the two environments assessed with a palm-oil-in Roraima.

  10. The mitogenome of Onchocerca volvulus from the Brazilian Amazonia focus

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    James L Crainey

    2016-01-01

    Full Text Available We report here the first complete mitochondria genome of Onchocerca volvulus from a focus outside of Africa. An O. volvulus mitogenome from the Brazilian Amazonia focus was obtained using a combination of high-throughput and Sanger sequencing technologies. Comparisons made between this mitochondrial genome and publicly available mitochondrial sequences identified 46 variant nucleotide positions and suggested that our Brazilian mitogenome is more closely related to Cameroon-origin mitochondria than West African-origin mitochondria. As well as providing insights into the origins of Latin American onchocerciasis, the Brazilian Amazonia focus mitogenome may also have value as an epidemiological resource.

  11. Deforestation and Carbon Stock Loss in Brazil's Amazonian Settlements.

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    Yanai, Aurora Miho; Nogueira, Euler Melo; de Alencastro Graça, Paulo Maurício Lima; Fearnside, Philip Martin

    2017-03-01

    We estimate deforestation and the carbon stock in 2740 (82 %) of the 3325 settlements in Brazil's Legal Amazonia region. Estimates are made both using available satellite data and a carbon map for the "pre-modern" period (prior to 1970). We used data from Brazil's Project for Monitoring Deforestation in Amazonia updated through 2013 and from the Brazilian Biomes Deforestation Monitoring Project (PMDBBS) updated through 2010. To obtain the pre-modern and recent carbon stocks we performed an intersection between a carbon map and a map derived from settlement boundaries and deforestation data. Although the settlements analyzed occupied only 8 % of Legal Amazonia, our results indicate that these settlements contributed 17 % (160,410 km 2 ) of total clearing (forest + non-forest) in Legal Amazonia (967,003 km 2 ). This represents a clear-cutting of 41 % of the original vegetation in the settlements. Out of this total, 72 % (115,634 km 2 ) was in the "Federal Settlement Project" (PA) category. Deforestation in settlements represents 20 % (2.6 Pg C) of the total carbon loss in Legal Amazonia (13.1 Pg C). The carbon stock in remaining vegetation represents 3.8 Pg C, or 6 % of the total remaining carbon stock in Legal Amazonia (58.6 Pg C) in the periods analyzed. The carbon reductions in settlements are caused both by the settlers and by external actors. Our findings suggest that agrarian reform policies contributed directly to carbon loss. Thus, the implementation of new settlements should consider potential carbon stock losses, especially if settlements are created in areas with high carbon stocks.

  12. Time Resolved Measurements of Primary Biogenic Aerosol Particles in Amazonia

    Science.gov (United States)

    Wollny, A. G.; Garland, R.; Pöschl, U.

    2009-04-01

    Biogenic aerosols are ubiquitous in the Earth's atmosphere and they influence atmospheric chemistry and physics, the biosphere, climate, and public health. They play an important role in the spread of biological organisms and reproductive materials, and they can cause or enhance human, animal, and plant diseases. Moreover, they influence the Earth's energy budget by scattering and absorbing radiation, and they can initiate the formation of clouds and precipitation as cloud condensation and ice nuclei. The composition, abundance, and origin of biogenic aerosol particles and components are, however, still not well understood and poorly quantified. Prominent examples of primary biogenic aerosol particles, which are directly emitted from the biosphere to the atmosphere, are pollen, bacteria, fungal spores, viruses, and fragments of animals and plants. During the Amazonian Aerosol Characterization Experiment (AMAZE-08) a large number of aerosol and gas-phase measurements were taken on a remote site close to Manaus, Brazil, during a period of five weeks in February and March 2008. This presented study is focused on data from an ultraviolet aerodynamic particle sizer (UVAPS, TSI inc.) that has been deployed for the first time in Amazonia. In this instrument, particle counting and aerodynamic sizing over the range of 0.5-20 µm are complemented by the measurement of UV fluorescence at 355 nm (excitation) and 420-575 nm (emission), respectively. Fluorescence at these wavelengths is characteristic for reduced pyridine nucleotides (e.g., NAD(P)H) and for riboflavin, which are specific for living cells. Thus particles exhibiting fluorescence signals can be regarded as "viable aerosols" or "fluorescent bioparticles" (FBAP), and their concentration can be considered as lower limit for the actual abundance of primary biogenic aerosol particles. Data from the UVAPS were averaged over 5 minute time intervals. The presence of bioparticles in the observed size range has been

  13. Brazilian Amazonia Deforestation Detection Using Spatio-Temporal Scan Statistics

    Science.gov (United States)

    Vieira, C. A. O.; Santos, N. T.; Carneiro, A. P. S.; Balieiro, A. A. S.

    2012-07-01

    The spatio-temporal models, developed for analyses of diseases, can also be used for others fields of study, including concerns about forest and deforestation. The aim of this paper is to quantitatively check priority areas in order to combat deforestation on the Amazon forest, using the space-time scan statistic. The study area location is at the south of the Amazonas State and cover around 297.183 kilometre squares, including the municipality of Boca do Acre, Labrea, Canutama, Humaita, Manicore, Novo Aripuana e Apui County on the north region of Brazil. This area has showed a significant change for land cover, which has increased the number of deforestation's alerts. Therefore this situation becomes a concern and gets more investigation, trying to stop factors that increase the number of cases in the area. The methodology includes the location and year that deforestation's alert occurred. These deforestation's alerts are mapped by the DETER (Detection System of Deforestation in Real Time in Amazonia), which is carry out by the Brazilian Space Agency (INPE). The software SatScanTM v7.0 was used in order to define space-time permutation scan statistic for detection of deforestation cases. The outcome of this experiment shows an efficient model to detect space-time clusters of deforestation's alerts. The model was efficient to detect the location, the size, the order and characteristics about activities at the end of the experiments. Two clusters were considered actives and kept actives up to the end of the study. These clusters are located in Canutama and Lábrea County. This quantitative spatial modelling of deforestation warnings allowed: firstly, identifying actives clustering of deforestation, in which the environment government official are able to concentrate their actions; secondly, identifying historic clustering of deforestation, in which the environment government official are able to monitoring in order to avoid them to became actives again; and finally

  14. BRAZILIAN AMAZONIA DEFORESTATION DETECTION USING SPATIO-TEMPORAL SCAN STATISTICS

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    C. A. O. Vieira

    2012-07-01

    Full Text Available The spatio-temporal models, developed for analyses of diseases, can also be used for others fields of study, including concerns about forest and deforestation. The aim of this paper is to quantitatively check priority areas in order to combat deforestation on the Amazon forest, using the space-time scan statistic. The study area location is at the south of the Amazonas State and cover around 297.183 kilometre squares, including the municipality of Boca do Acre, Labrea, Canutama, Humaita, Manicore, Novo Aripuana e Apui County on the north region of Brazil. This area has showed a significant change for land cover, which has increased the number of deforestation's alerts. Therefore this situation becomes a concern and gets more investigation, trying to stop factors that increase the number of cases in the area. The methodology includes the location and year that deforestation’s alert occurred. These deforestation's alerts are mapped by the DETER (Detection System of Deforestation in Real Time in Amazonia, which is carry out by the Brazilian Space Agency (INPE. The software SatScanTM v7.0 was used in order to define space-time permutation scan statistic for detection of deforestation cases. The outcome of this experiment shows an efficient model to detect space-time clusters of deforestation’s alerts. The model was efficient to detect the location, the size, the order and characteristics about activities at the end of the experiments. Two clusters were considered actives and kept actives up to the end of the study. These clusters are located in Canutama and Lábrea County. This quantitative spatial modelling of deforestation warnings allowed: firstly, identifying actives clustering of deforestation, in which the environment government official are able to concentrate their actions; secondly, identifying historic clustering of deforestation, in which the environment government official are able to monitoring in order to avoid them to became

  15. Multi year aerosol characterization in the tropical Andes and in adjacent Amazonia using AERONET measurements

    Science.gov (United States)

    Pérez-Ramírez, Daniel; Andrade-Flores, Marcos; Eck, Thomas F.; Stein, Ariel F.; O'Neill, Norman T.; Lyamani, Hassan; Gassó, Santiago; Whiteman, David N.; Veselovskii, Igor; Velarde, Fernando; Alados-Arboledas, L.

    2017-10-01

    This work focuses on the analysis of columnar aerosol properties in the complex geophysical tropical region of South America within 10-20° South and 50-70° West. The region is quite varied and encompasses a significant part of Amazonia (lowlands) as well as high mountains in the Andes (highlands,∼4000 m a.s.l.). Several AERONET stations were included to study the aerosol optical characteristics of the lowlands (Rio Branco, Ji Parana and Cuiaba in Brazil and Santa Cruz in Bolivia) and the highlands (La Paz, Bolivia) during the 2000-2014 period. Biomass-burning is by far the most important source of aerosol in the lowlands, particularly during the dry season (August-October). Multi-annual variability was investigated and showed very strong burning activity in 2005, 2006, 2007 and 2010. This resulted in smoke characterized by correspondingly strong, above-average AODs (aerosol optical depths) and homogeneous single scattering albedo (SSA) across all the stations (∼0.93). For other years, however, SSA differences arise between the northern stations (Rio Branco and Ji Parana) with SSAs of ∼0.95 and the southern stations (Cuiaba and Santa Cruz) with lower SSAs of ∼0.85. Such differences are explained by the different types of vegetation burned in the two different regions. In the highlands, however, the transport of biomass burning smoke is found to be sporadic in nature. This sporadicity results in highly variable indicators of aerosol load and type (Angstrom exponent and fine mode fraction) with moderately significant increases in both. Regional dust and local pollution are the background aerosol in this highland region, whose elevation places it close to the free troposphere. Transported smoke particles were generally found to be more optical absorbing than in the lowlands: the hypothesis to explain this is the significantly higher amount of water vapor in Amazonia relative to the high mountain areas. The air-mass transport to La Paz was investigated using

  16. A utilização de uma rede neural artificial para previsão da incidência da malária no município de Cantá, estado de Roraima Use of an artificial neural network to predict the incidence of malaria in the city of Cantá, state of Roraima

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    Guilherme Bernardino da Cunha

    2010-10-01

    Full Text Available INTRODUÇÃO: A malária é uma doença endêmica na Amazônia Legal Brasileira, apresentando riscos diferentes para cada região. O Município de Cantá, no Estado de Roraima, apresentou para todo o período estudado, um dos maiores índices parasitários anuais do Brasil, com valor sempre maior que 50. O presente estudo visa à utilização de uma rede neural artificial para previsão da incidência da malária nesse município, a fim de auxiliar os coordenadores de saúde no planejamento e gestão dos recursos. MÉTODOS: Os dados foram coletados no site do Ministério da Saúde, SIVEP - Malária entre 2003 e 2009. Estruturou-se uma rede neural artificial com três neurônios na camada de entrada, duas camadas intermediárias e uma camada de saída com um neurônio. A função de ativação foi à sigmoide. No treinamento, utilizou-se o método backpropagation, com taxa de aprendizado de 0,05 e momentum 0,01. O critério de parada foi atingir 20.000 ciclos ou uma meta de 0,001. Os dados de 2003 a 2008 foram utilizados para treinamento e validação. Comparam-se os resultados com os de um modelo de regressão logística. RESULTADOS: Os resultados para todos os períodos previstos mostraram-se que as redes neurais artificiais obtiveram um menor erro quadrático médio e erro absoluto quando comparado com o modelo de regressão para o ano de 2009. CONCLUSÕES: A rede neural artificial se mostrou adequada para um sistema de previsão de malária no município estudado, determinando com pequenos erros absolutos os valores preditivos, quando comparados ao modelo de regressão logística e aos valores reais.INTRODUCTION: Malaria is endemic in the Brazilian Amazon region, with different risks for each region. The City of Cantá, State of Roraima, presented one of the largest annual parasite indices in Brazil for the entire study period, with a value always greater than 50. The present study aimed to use an artificial neural network to predict the

  17. Mapeamento e Caracterização Ambiental das Áreas Apícolas dos Municípios de Mucajaí e Cantá do Estado de Roraima. Mapping and Environmental Description of Beekeeping Areas in Mucajaí and Cantá Municipalities of Roraima State.

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    Dorvanir da S. Barros

    2008-07-01

    Full Text Available Este trabalho teve como objetivo mapear, identificar e caracterizar ambientalmente as áreas apícolas dos municípios de Mucajaí e Cantá do Estado de Roraima, a partir de informações referentes às cartas temáticas de geologia, geomorfologia, pedologia, vegetação, hidrografia, aptidão agrícola e informações da atividade apícola local. Um mapa básico destes municípios foi gerado, numa escala de 1:200.000 e 1:500.000, respectivamente, correlacionados com as cartas temáticas das áreas apícolas e localização dos apiários. Constatou-se que todas as áreas são favoráveis a exploração apícola, visto que, tanto em áreas inaptas e/ou restritas as culturas de ciclo curto e longo, da diversidade da vegetação, da rede de drenagem, contribuem para o desenvolvimento e ampliação da apicultura. Consubstanciando para cadastro dos apicultores junto ao Programa Nacional de Georeferenciamento das áreas apícolas do País, usufruindo dos benefícios de um sistema de informações geográficas (SIG, consolidando uma melhor alternativa de preservação das florestas em áreas com severas restrições a pecuária e a agricultura. Ressaltando que a exploração apícola engloba o tripé da sustentabilidade: O econômico, o social e o Ecológico. = This study aimed to map, identify and environmentally describe beekeeping areas of two municipalities in the state of Roraima, derived from information related to thematic maps on geology, geomorphology, pedology, vegetation, hydrography, agricultural capability and geopositioning of beekeeping areas. It was drawn a cartographic map of the two municipalities on the scales of 1:200.000 and 1:500.000, respectively, correlated with the thematic maps describing the apiculture areas. It appeared that all areas are in favor of holding beekeeping. So, those areas unfit and / or restricted to the short and long cycle culture, as well as those areas with a diversity of vegetation, and areas where a

  18. Phytosanitary diagnostic and practices associated with pesticide use in gardens in a protected environment in the city of Boa Vista in Roraima. = Diagnóstico fitossanitário e de práticas associadas ao uso de agrotóxicos nas hortas em ambiente protegido em Boa Vista - Roraima.

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    Antonio Cesar Silva Lima

    2011-08-01

    Full Text Available The objective of this study was to diagnose pests, diseases, weeds, and practices associated with the use of agrochemicals on the production of vegetables under protected conditions in Boa Vista, Roraima, Brazil. The descriptive study was conducted in urban and rural areas during February to April 2008, in the gardens monitored by Project Greenhouse, administered by the Municipal Development agricultural Secretary of the City. The data collection instrument was a semistructured questionnaire with 50 questions, applied in situ without notice to 75 farmers (47% of the population under study.Data were analyzed by descriptive statistics. After analyzing the data it was found that the whitefly, aphids, thrips and caterpillars were the insect pests that needed to be better controlled. The principal diseases were blight and leaf blight. Significant weed pests originated from the species of the families Poaceae, Cyperaceae, Amaranthaceae, and Portulacaeae. Relative to the use of pesticides, the results showed that 68% of farmers used insecticides, 24% fungicides, and 8% herbicides; 92% indicated that they had received some kind of technical guidance and 41.3% seek the technical assistance in order to acquire a pesticide. Therefore, we conclude that there is a high incidence of problems in plant vegetable gardens, intensive use of pesticides, a variety of formulations of insecticides, fungicides and herbicides associated with the adoption of practices and attitudes of risk for farmers, which can aggravate the direct and indirect problems of intoxication, and cause contamination to the environment. =Objetivou-se com esse trabalho fazer o diagnóstico das pragas, doenças, plantas daninhas e das práticas associadas ao uso dos agrotóxicos utilizados na produção de hortaliças, em ambiente protegido, no município de Boa Vista, Roraima. O estudo descritivo foi realizado em área urbana e rural, nos meses de fevereiro a abril de 2008, nas hortas atendidas

  19. Astrocaryum (palmae in Amazonia a preliminary treatment

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    1992-01-01

    Full Text Available ASTROCARYUM (PALMAE EN AMAZONIE. TRAITEMENT PRÉLIMINAIRE. Le genre Astrocaryum est composé de 24 espèces amazoniennes: cinq appartiennent au sous-genre Pleiogynanthus et 19 au sous-genre Monogynanthus (3 à la section Munbaca et 16 à la section Ayri. Une clé d’identification est proposée, ainsi que la description de chaque espèce, complétée par de nouvelles observations et suivie de notes sur la distribution géographique, l’écologie et les utilisations. Six espeses nouvelles sont décrites. ASTROCARYUM (PALMAE EN LA AMAZONIA. TRATAMIENTO PRELIMINAR. Astrocaryum consta de 24 especies amazónicas, 5 de las cuales pertenecen al subgénero Pleiogynanthus y 19 al subgénero Monogynanthus (3 a la sección Munbaca, 16 a la sección Ayri. Se presenta una clave para diferenciar las especies, y para cada una, su descripción con nuevos datos, así como notas sobre la distribución geográfica, la ecología y los usos. Se describen seis especies nuevas. In the Amazon, Astrocaryum includes 24 species of which five belong to the subgenus Pleiogynanthus and 19 to the subgenus Monogynanthus - three in the section Munbaca and 16 in the section Ayri. A key to these 24 species is presented followed by description based on new data, and notes on their distribution, ecology and uses. Six new species are described.

  20. Effects of reduced-impact logging on fish assemblages in central Amazonia.

    Science.gov (United States)

    Dias, Murilo S; Magnusson, William E; Zuanon, Jansen

    2010-02-01

    In Amazonia reduced-impact logging, which is meant to reduce environmental disturbance by controlling stem-fall directions and minimizing construction of access roads, has been applied to large areas containing thousands of streams. We investigated the effects of reduced-impact logging on environmental variables and the composition of fish in forest streams in a commercial logging concession in central Amazonia, Amazonas State, Brazil. To evaluate short-term effects, we sampled 11 streams before and after logging in one harvest area. We evaluated medium-term effects by comparing streams in 11 harvest areas logged 1-8 years before the study with control streams in adjacent areas. Each sampling unit was a 50-m stream section. The tetras Pyrrhulina brevis and Hemigrammus cf. pretoensis had higher abundances in plots logged > or =3 years before compared with plots logged fish composition did not differ two months before and immediately after reduced-impact logging. Temperature and pH varied before and after logging, but those differences were compatible with normal seasonal variation. In the medium term, temperature and cover of logs were lower in logged plots. Differences in ordination scores on the basis of relative fish abundance between streams in control and logged areas changed with time since logging, mainly because some common species increased in abundance after logging. There was no evidence of species loss from the logging concession, but differences in log cover and ordination scores derived from relative abundance of fish species persisted even after 8 years. For Amazonian streams, reduced-impact logging appears to be a viable alternative to clear-cut practices, which severely affect aquatic communities. Nevertheless, detailed studies are necessary to evaluated subtle long-term effects.

  1. Fenologia de Cornops aquaticum (Orthoptera: Acrididae associado a Eichhornia crassipes (Pontederiaceae em um Lago de Várzea na Amazônia Central, Brasil Phenology of Cornops aquaticum (Orthoptera: Acrididae associated with Eichhornia crassipes (Pontederiaceae in a Floodplain Lake in Central Amazonia, Brazil

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    Carlos Elias Braga

    2011-12-01

    Full Text Available O gafanhoto Neotropical Cornops aquaticum (Bruner vive associado às macrófitas da família Pontederiaceae da qual se alimenta. Nos lagos da Amazônia Central, Eichhornia crassipes (Mart. Solms (mururé ou aguapé é considerada a planta hospedeira de maior importante para este gafanhoto. Esse trabalho teve o objetivo de realizar um estudo fenológico de adultos e ninfas desse gafanhoto em associação a sua planta hospedeira, frente ao regime hidrológico da Amazônia Central. Tal estudo foi realizado entre os meses de abril de 2006 a agosto de 2007 no Lago Camaleão (03º17'05"S 60º11'11"W, na várzea da Amazônia Central. Para isso, utilizou-se uma rede entomológica (70 cm de diâmetro adaptada para a captura dos gafanhotos. Onde foram capturados 850 exemplares (296 adultos e 554 ninfas. Observou-se que a abundância e a biomassa de adultos e de ninfas de C. aquaticum, bem como de sua macrófita hospedeira, estão relacionados com a oscilação sazonal do nível do rio (pulso de inundação.La tucura Neotropical, Cornops aquaticum (Bruner, vive asociada a las macrófitas de la familia Pontederiaceae, de las cuales se alimenta. En los lagos de la Amazonia Central, Eichhornia crassipes (Mart. Solms (camalote o aguape constituye la planta huésped más importante de esta tucura. El objetivo de este trabajo fue estudiar la fenología de los adultos y las ninfas de C. aquaticum en los camalotales de E. crassipes, en relación al régimen hidrológico de la Amazonia Central. Los muestreos se realizaron entre los meses de abril de 2006 a agosto de 2007, en el Lago Camaleón (03º17'05"S 60º 11 '11 "O en la Várzea de la Amazonia Central. Los individuos fueron capturados desde una embarcación a motor, utilizando una red entomológica de 70 cm de diámetro. Durante este estudio, se capturaron un total de 850 ejemplares (296 adultos y 554 ninfas. Se observó que la abundancia y la biomasa de los adultos y de las ninfas de C. aquaticum, así como

  2. Catalogue of distribution of lizards (Reptilia: Squamata) from the Brazilian Amazonia. III. Anguidae, Scincidae, Teiidae.

    Science.gov (United States)

    Ribeiro-Júnior, Marco A; Amaral, Silvana

    2016-12-09

    We present distribution data of all Anguidae, Scincidae, and Teiidae lizards known from the Brazilian Amazonia, totaling 29 species-level taxa, belonging to 14 genera. This represents 11 more species-level taxa than previously reported for these families in this area. Data were based on literature and 46,806 specimens deposited in three North American and eight Brazilian museums, including the main collections harboring Amazonian material. Most species (~55%) are endemic to Amazonia. Except for Ameiva ameiva, that is present in several environments and domains, non-endemic species are either associated with open dry (semideciduous) forest or open vegetation (savanna) enclaves in Amazonia, occupying similar environments outside Amazonia, gallery forests within the Cerrado, or present disjunct populations in the Atlantic Forest. As a whole, six taxa are widespread in Amazonia, four are restricted to eastern Amazonia, four to western Amazonia, three to southwestern Amazonia, one to northern Amazonia, and seven to the southern peripheral portion of Amazonia. Besides, two species present apparently more restricted, unique distributions. Only three species have a distribution that is congruent with one of the areas of endemism (AE) recognized for other organisms (birds and primates), of which two occur in AE Guiana and one in AE Inambari.

  3. Paleoclimates of Amazonia: An ice-age view

    NARCIS (Netherlands)

    Bush, M.B.; De Oliveira, P.E.; Raczka, M.F.; Gosling, W.D.; Mayle, F.E.; McMichael, C.H.; Urrego, D.H.; de Souza Carvalho, I.; Garcia, M.J.; Cunha Lana, C.; Strohschoen Jr., O.

    2014-01-01

    A growing body of evidence points to climatic complexity during the Ice-Ages. Amazonia does not respond uniformly to modern climatic forcing, and the same was true of the past. Although some climatic forcings were probably expressed everywhere, they were manifested differently. Consequently, climate

  4. Evapotranspiration of deforested areas in central and southwestern Amazonia

    NARCIS (Netherlands)

    Randow, von R.C.S.; Randow, C.; Hutjes, R.W.A.; Tomasella, J.; Kruijt, B.

    2012-01-01

    Considering the high rates of evapotranspiration of Amazonian forests, understanding the impacts of deforestation on water loss rates is important for assessing those impacts on a regional and global scale. This paper quantifies evapotranspiration rates in two different pasture sites in Amazonia and

  5. Molluscan radiations and landscape evolution in Miocene Amazonia

    NARCIS (Netherlands)

    Wesselingh, F.P.

    2008-01-01

    This PhD study aims to exploit the rich archive provided by the Miocene mollusc fauna of the Pebas Formation and other inland Miocene Amazonian formations to reconstruct landscape evolution and biotic development in lowland Amazonia during the Neogene. Over 160 samples from more than 70 Pebas

  6. Fenologia da andiroba (Carapa guianensis, Aubl., Meliaceae no sul do estado de Roraima

    Directory of Open Access Journals (Sweden)

    Maria Rutinéia Nobre Pereira

    2012-03-01

    Full Text Available http://dx.doi.org/10.5902/198050985078O presente estudo foi realizado com o objetivo de estudar o padrão fenológico da espécie arbórea Carapa guianensis, Aubl., em floresta natural localizada no sul do estado de Roraima, procurando relacionar a frequência de ocorrência das fenofases às condições pluviométricas do período. Para o levantamento fenológico foram selecionados 20 indivíduos adultos localizados em uma parcela permanente de 9 ha. As observações fenológicas ocorreram quinzenalmente de fevereiro de 2006 a fevereiro de 2009, registrando-se a presença ou ausência dos eventos de floração, frutificação e mudança foliar para cada árvore. Para analisar a influência da precipitação na fenologia da espécie foi utilizado o coeficiente de correlação de Spearman e, para estimar a sincronia dos eventos fenológico utilizou-se o índice de sincronia da população (Z. A floração da andiroba mostrou-se subanual, sincrônica e correlacionada negativamente com precipitação no período do evento fenológico. Foram observados dois ciclos de floração, sendo um longo com inicio em outubro, estendendo-se para o ano seguinte, por um período médio de 9 meses, e um curto com duração de dois meses (julho a agosto. A frutificação é anual, longa e sincrônica, e correlacionou-se positivamente com a precipitação. A época ideal para a coleta dos frutos maduros no local estudado é durante o período chuvoso, que compreende abril a julho. A emissão de folhas ocorreu de forma contínua e não se correlacionou com a precipitação. Observou-se uma maior proporção de indivíduos perdendo folhas, entre os meses de agosto a novembro, que caracterizam um período de transição entre a época seca e chuvosa, com sensível redução de precipitação.

  7. Droughts in Amazonia: Spatiotemporal Variability, Teleconnections, and Seasonal Predictions

    Science.gov (United States)

    Lima, Carlos H. R.; AghaKouchak, Amir

    2017-12-01

    Most Amazonia drought studies have focused on rainfall deficits and their impact on river discharges, while the analysis of other important driver variables, such as temperature and soil moisture, has attracted less attention. Here we try to better understand the spatiotemporal dynamics of Amazonia droughts and associated climate teleconnections as characterized by the Palmer Drought Severity Index (PDSI), which integrates information from rainfall deficit, temperature anomalies, and soil moisture capacity. The results reveal that Amazonia droughts are most related to one dominant pattern across the entire region, followed by two seesaw kind of patterns: north-south and east-west. The main two modes are correlated with sea surface temperature (SST) anomalies in the tropical Pacific and Atlantic oceans. The teleconnections associated with global SST are then used to build a seasonal forecast model for PDSI over Amazonia based on predictors obtained from a sparse canonical correlation analysis approach. A unique feature of the presented drought prediction method is using only a few number of predictors to avoid excessive noise in the predictor space. Cross-validated results show correlations between observed and predicted spatial average PDSI up to 0.60 and 0.45 for lead times of 5 and 9 months, respectively. To the best of our knowledge, this is the first study in the region that, based on cross-validation results, leads to appreciable forecast skills for lead times beyond 4 months. This is a step forward in better understanding the dynamics of Amazonia droughts and improving risk assessment and management, through improved drought forecasting.

  8. Ocorrência de moscas-das-frutas (Diptera: Tephritidae em mangueiras (Mangifera indica L. em Boa Vista, Roraima = The occurrence of fruit fly (Diptera: Tephritidae in mango (Mangifera indica L. in Boa Vista, Roraima

    Directory of Open Access Journals (Sweden)

    Adriana Bezerra Lima

    2012-08-01

    Full Text Available Um estudo foi conduzido no período de junho de 2007 a janeiro de 2008, em pomares comerciais de manga das variedades: Tommy Atkins, Haden e Palmer sendo 3 ha de cada cultivar, localizado na região do Bom Intento no Município de Boa Vista. Os espécimes de moscas-das-frutas foram coletados, por meio de armadilhas, confeccionadas com garrafas pet, que foram penduradas na copa das árvores a 1,60 m de altura. Como atrativo alimentar foi utilizado 200 mL de suco de maracujá a 30%. Foram utilizadas nove armadilhas, sendo uma armadilha por hectare. Semanalmente as armadilhas eram examinadas, ocasião em que se substituía o atrativo e os insetos capturados retirados e colocados em frascos de vidro devidamente etiquetados e transportados ao Laboratório de Entomologia do Centro de Ciências Agrárias da Universidade Federal de Roraima. As identificações dos espécimes foram feitas no Instituto Nacional de Pesquisa da Amazônia - INPA. No período de oito meses foram coletados 24 espécimes adultos do gênero Anastrepha (nove fêmeas e 15 machos. Quatro espécies foram identificadas: A. serpentina, A. striata, A. obliqua e A. turpinae. A maior frequência foi A. serpentina (44,44%, seguida de A. striata e A. obliqua ambas com 22,22% e A. turpinae com 11,11%. Os meses de maior ocorrência de Anastrepha spp. foram junho, julho e agosto. Este é o primeiro registro da espécie Anastrepha turpinae Stone, 1942, em Roraima. The study was done during th period of June 2007 to January of 2008, in commercial mango orchards having: 3 ha of cv. Tommy Atkins, 3 ha of cv. Haden. and 3 ha of cv. Palmer, located at Bom Intento in the municipal district of Boa Vista - RR. The specimens of fruit flies were collected, by trapping, made with transparent bottles pet, which were hung in the cup of the trees at 1.60 m of height. 200 mL of passion fruit juice (30% was used as an attractant feed; 9 traps were used, being one trap for hectare. Weekly The traps were

  9. HARVEST TIME AND PHYSIOLOGIC QUALITY OF SEEDS IN IRRIGATED RICE (Oryza sativa cv. BRS RORAIMA ÉPOCA DE COLHEITA E QUALIDADE FISIOLÓGICA DE SEMENTES EM ARROZ IRRIGADO (Oryza sativa cv. BRS RORAIMA

    Directory of Open Access Journals (Sweden)

    Oscar José Smiderle

    2008-09-01

    Full Text Available

    Harvest time is one of most important factors influencing rice seed characteristics for purpose of either planting or milling. With the objective to determine a proper harvesting  time, irrigated rice seeds of cultivar BRS Roraima were harvested at 15, 22, 29, 36, 43 and 50 days after flowering (DAF, and assessed according to humidity, viability, dry mass of 1,000 seeds, whole grain yield, productivity and storability. Seeds harvested 29 DAF showed high quality and its productivity was equivalent to the subsequent periods. Seeds harvested 50 DAF showed good performance, except for whole grain yield. Harvests 15 and 22 DAF were unsuitable, reducing the physiologic quality of seeds, mill efficiency and high initial humidity. The adequate harvest time for cultivar BRS Roraima is between 29 and 43 DAF, when seeds present higher yield, dry mass, whole grain yield, physiologic quality and storability.

    KEY-WORDS: Physiologic quality; whole grain; humidity.

    A época de colheita é um dos fatores mais importantes que influenciam as características da semente de arroz, seja para semeadura ou para consumo. Com o objetivo de determinar a época adequada de colheita de arroz irrigado, para a cultivar BRS Roraima, sementes foram colhidas aos 15, 22, 29, 36, 43 e 50 dias após o florescimento (DAF e avaliadas quanto à umidade, viabilidade, massa seca de 1.000 sementes, rendimento de grãos inteiros, produtividade e armazenabilidade. As sementes colhidas aos 29 DAF

  10. Neogene Amazonia: Introduction to the special issue Journal of South American Earth Sciences, New contributions on Neogene geography and depositional environments in Amazonia

    NARCIS (Netherlands)

    Hoorn, C.; Vonhof, H.B.

    2006-01-01

    The paleontological data presented in this special issue provide a new insight into species migration and radiation in Amazonia during the Miocene. At the time, Amazonia was characterized by a very extensive, long-lived, semi-isolated, freshwater wetland ecosystem that was supplied with water and

  11. [Forum: health and indigenous peoples in Brazil. Introduction].

    Science.gov (United States)

    Welch, James R

    2014-04-01

    This Forum on Health and Indigenous Peoples in Brazil explores contemporary challenges to indigenous health and health politics in Brazil. The short collection of articles that follow are based on presentations, originally given at the Indigenous Health Working Group panel at the 10th Brazilian Public Health Conference in Rio Grande do Sul State, by professors Carlos E. A. Coimbra Jr. (Escola Nacional de Saúde Pública, Fundação Oswaldo Cruz), Marina Denise Cardoso (Universidade Federal de São Carlos) and Eliana E. Diehl (Universidade Federal de Santa Catarina) with Marcos A. Pellegrini (Universidade Federal de Roraima). In this short Introduction, I introduce these contributions, taking as a point of reference a local example of healthcare inequity derived from a presentation at the same panel by Paulo F. Supretaprã, indigenous community leader from Etênhiritipá village, Mato Grosso State.

  12. [The Sanumá-Yanomami medical system and indigenous peoples' health policy in Brazil].

    Science.gov (United States)

    Guimarães, Sílvia Maria Ferreira

    2015-10-01

    The purpose of this study is to discuss how the Sanumá indigenous people, a subgroup of the Yanomami linguistic family, located in northern Roraima State, Brazil, interacts with and relates to the public policy for indigenous people's health. Missionaries and Brazilian government and non-governmental organization employees are the agents with whom the Sanumá had to deal during the implementation of a healthcare policy. The ethnography of this interrelationship, permeated by moments of epidemic outbreaks, clashes, and attempts at collaboration, raises questions on the implementation of health services in indigenous territories.

  13. Carbon and nutrient stocks of three Fabaceae trees used for forest restoration and subjected to fertilization in Amazonia.

    Science.gov (United States)

    Jaquetti, Roberto K; Gonçalves, José Francisco C

    2017-01-01

    Amazonia is crucial to global carbon cycle. Deforestation continues to be one of the main causes of the release of C into the atmosphere, but forest restoration plantations can reverse this scenario. However, there is still diffuse information about the C and nutrient stocks in the vegetation biomass. We investigated the carbon and nutrient stocks of Fabaceae trees (Inga edulis, Schizolobium amazonicum and Dipteryx odorata) subjected to fertilization treatments (T1 - no fertilization; T2 - chemical; T3 - organic; and T4 - organic and chemical fertilization) in a degraded area of the Balbina Hydroelectric Dam, AM - Brazil. As an early successional species, I. edulis stocked more C and nutrients than the other two species independent of the fertilization treatment, and S. amazonicum stocked more C than D. odorata under T1 and T4. The mixed species plantation had the potential to stock 4.1 Mg C ha-1 year-1, while I. edulis alone could stock 9.4 Mg C ha-1 year-1. Mixing species that rapidly assimilate C and are of significant ecological and commercial value (e.g., Fabaceae trees) represents a good way to restore degraded areas. Our results suggest that the tested species be used for forest restoration in Amazonia.

  14. Carbon and nutrient stocks of three Fabaceae trees used for forest restoration and subjected to fertilization in Amazonia

    Directory of Open Access Journals (Sweden)

    ROBERTO K. JAQUETTI

    2017-08-01

    Full Text Available ABSTRACT Amazonia is crucial to global carbon cycle. Deforestation continues to be one of the main causes of the release of C into the atmosphere, but forest restoration plantations can reverse this scenario. However, there is still diffuse information about the C and nutrient stocks in the vegetation biomass. We investigated the carbon and nutrient stocks of Fabaceae trees (Inga edulis, Schizolobium amazonicum and Dipteryx odorata subjected to fertilization treatments (T1 - no fertilization; T2 - chemical; T3 - organic; and T4 - organic and chemical fertilization in a degraded area of the Balbina Hydroelectric Dam, AM - Brazil. As an early successional species, I. edulis stocked more C and nutrients than the other two species independent of the fertilization treatment, and S. amazonicum stocked more C than D. odorata under T1 and T4. The mixed species plantation had the potential to stock 4.1 Mg C ha-1 year-1, while I. edulis alone could stock 9.4 Mg C ha-1 year-1. Mixing species that rapidly assimilate C and are of significant ecological and commercial value (e.g., Fabaceae trees represents a good way to restore degraded areas. Our results suggest that the tested species be used for forest restoration in Amazonia.

  15. Soil-vegetation relationships on a banded ironstone 'island', Carajás Plateau, Brazilian Eastern Amazonia.

    Science.gov (United States)

    Nunes, Jaquelina A; Schaefer, Carlos E G R; Ferreira Júnior, Walnir G; Neri, Andreza V; Correa, Guilherme R; Enright, Neal J

    2015-01-01

    Vegetation and soil properties of an iron-rich canga (laterite) island on the largest outcrop of banded-iron formation in Serra de Carajás (eastern Amazonia, Brazil) were studied along a topographic gradient (738-762 m asl), and analyzed to test the hypothesis that soil chemical and physical attributes play a key role in the structure and floristic composition of these plant communities. Soil and vegetation were sampled in eight replicate plots within each of the four vegetation types. Surface (0-10 cm) soil samples from each plot were analyzed for basic cations, N, P and plant species density for all species was recorded. CCA ordination analysis showed a strong separation between forest and non-forest sites on the first axis, and between herbaceous and shrubby campo rupestre on the second axis. The four vegetation types shared few plant species, which was attributed to their distinctive soil environments and filtering of their constituent species by chemical, physical and hydrological constraints. Thus, we can infer that Edaphic (pedological) factors are crucial in explaining the types and distributions of campo rupestre vegetation associated with ferruginous ironstone uplands (Canga) in Carajás, eastern Amazonia, therefore the soil properties are the main drivers of vegetation composition and structure on these ironstone islands.

  16. Tiempos afroindígenas en la Amazonia brasileña. Primera mitad del siglo XIX

    Directory of Open Access Journals (Sweden)

    Ruiz-Peinado Alonso, José Luis

    2010-08-01

    Full Text Available During the first half of the nineteenth century, the Brazilian Amazonia was marked by extraordinary political-military instability: its belated support of Brazil’s independence (1823, the discussion on slavery and the explosion of the Cabanagem. During this period the leading figures were not only the Portuguese-Brazilian political elites, but also the different groups of fugitive slaves and natives who operated along the vast and complicated border areas, alert to revolutionary ideas coming from abroad, and who played an essential role in the construction of the specificity of northern Brazil.

    La Amazonia brasileña durante la primera mitad del siglo XIX estuvo marcada por una extraordinaria inestabilidad político-militar. Su adhesión tardía a la independencia de Brasil (1823, el debate sobre la esclavitud y la explosión de la Cabanagem fueron procesos que tuvieron como protagonistas no sólo a las elites políticas lusobrasileñas, sino también a diferentes grupos cimarrones e indígenas que actuaban desde amplios e intrincados espacios de frontera, atentos a las ideas revolucionarias que provenían del exterior y que jugaron un papel fundamental en la construcción de la especificidad del norte de Brasil.

  17. Floristic survey of herbaceous and subshrubby aquatic and palustrine angiosperms of Viruá National Park, Roraima, Brazil

    OpenAIRE

    Costa, Suzana Maria; Barbosa, Tiago Domingos Mouzinho; Bittrich, Volker; do Amaral, Maria do Carmo Estanislau

    2016-01-01

    Abstract We provide and discuss a floristic survey of herbaceous and subshrubby aquatic and palustrine angiosperms of Viru? National Park (VNP). The VNP is located in the northern Amazon basin and displays phytophysiognomies distributed in a mosaic where these plants occur, as flooded forests, hydromorphic white-sand savannas, ?buritizais? and waterbodies. After expeditions between February/2010 and January/2015 and the analysis of specimens from regional herbaria, we list 207 species of herb...

  18. Amazon soil charcoal: Pyrogenic carbon stock depends of ignition source distance and forest type in Roraima, Brazil.

    Science.gov (United States)

    da Silva Carvalho, Lidiany C; Fearnside, Philip M; Nascimento, Marcelo T; Barbosa, Reinaldo I

    2018-04-18

    Pyrogenic carbon (PyC) derived from charcoal particles (paleo + modern) deposited in the soil column has been little studied in the Amazon, and our understanding of the factors that control the spatial and vertical distribution of these materials in the region's forest soils is still unclear. The objective of this study was to test the effect of forest type and distance from the ignition source on the PyC stocks contained in macroscopic particles of soil charcoal (≥2 mm; 1 m depth) dispersed in ecotone forests of the northern Brazilian Amazon. Thirty permanent plots were set up near a site that had been occupied by pre-Columbian and by modern populations until the late 1970s. The sampled plots represent seasonal and ombrophilous forests that occur under different hydro-edaphic restrictions. Our results indicate that the largest PyC stock was spatially dependent on distance to the ignition source ( 50 cm) in seasonal forests was limited by hydro-edaphic impediments that restricted the occurrence of charcoal. These results suggest that PyC stocks derived from macroscopic charcoal particles in the soil of this Brazilian Amazon ecotone region are controlled by the distance from the ignition source of the fire, and that forest types with higher hydro-edaphic restrictions can inhibit formation and accumulation of charcoal. Making use of these distinctions reduces uncertainty and improves our ability to understand the variability of PyC stocks in forests with a history of fire in the Amazon. © 2018 John Wiley & Sons Ltd.

  19. Greenhouse gases study in Amazonia; Estudo de gases de efeito estufa na Amazonia

    Energy Technology Data Exchange (ETDEWEB)

    D' Amelio, Monica Tais Siqueira

    2006-07-01

    The Amazon plays an important role on the global carbon cycle, as changing as carbon storage, since Amazon Basin is the biggest area of tropical forest, around 50% of global. Natural's process, deforestation, and use land are CO{sub 2} sources. The Amazon forest is a significant source of N{sub 2}O by soil process, and CH{sub 4} by anaerobic process like flooded areas, rice cultures, and others sources. This project is part of the LBA project (Large-Scale Biosphere Atmosphere Experiment in Amazonia), and this project is 'Vertical profiles of carbon dioxide and other trace gas species over the Amazon basin using small aircraft'. Since December 2000 vertical profiles of CO{sub 2}, CH{sub 4}, CO, H{sub 2}, N{sub 2}O and SF{sub 6} have been measured above central Amazonia. The local sampling was over Tapajos National Forest, a primary forest in Para State, where had a CO{sub 2} flux tower and an east impact area with sources like animals, rice cultivation, biomass burning, etc, to compare the influence of an impact area and a preserved area in the profiles. The Reserva Biologica de Cuieiras, at Amazon State, is the other studied place, where there already exists a CO{sub 2} flux tower, and an east preserved area at this State, to compare with the Cuieiras. The sampling has been carried out on vertical profile from 1000 ft up to 12000 ft using a semi-automated sampling package developed at GMD/NOAA and a small aircraft. The analysis uses the MAGICC system (Multiple Analysis of Gases Influence Climate Change) which is installed at the Atmospheric Chemistry Laboratory (LQA) in IPEN (Instituto de Pesquisas Energeticas e Nucleares). The results showed that all gases studied, except H{sub 2} gas, has been following the global trend. At the Para State, for the studied years, the Amazonian Forest performed as small CO{sub 2} sink. To compare Wet and Dry Seasons, subtracted the Ascension concentration values in the period to remove the global influence. So that

  20. Greenhouse gases study in Amazonia; Estudo de gases de efeito estufa na Amazonia

    Energy Technology Data Exchange (ETDEWEB)

    D' Amelio, Monica Tais Siqueira

    2006-07-01

    The Amazon plays an important role on the global carbon cycle, as changing as carbon storage, since Amazon Basin is the biggest area of tropical forest, around 50% of global. Natural's process, deforestation, and use land are CO{sub 2} sources. The Amazon forest is a significant source of N{sub 2}O by soil process, and CH{sub 4} by anaerobic process like flooded areas, rice cultures, and others sources. This project is part of the LBA project (Large-Scale Biosphere Atmosphere Experiment in Amazonia), and this project is 'Vertical profiles of carbon dioxide and other trace gas species over the Amazon basin using small aircraft'. Since December 2000 vertical profiles of CO{sub 2}, CH{sub 4}, CO, H{sub 2}, N{sub 2}O and SF{sub 6} have been measured above central Amazonia. The local sampling was over Tapajos National Forest, a primary forest in Para State, where had a CO{sub 2} flux tower and an east impact area with sources like animals, rice cultivation, biomass burning, etc, to compare the influence of an impact area and a preserved area in the profiles. The Reserva Biologica de Cuieiras, at Amazon State, is the other studied place, where there already exists a CO{sub 2} flux tower, and an east preserved area at this State, to compare with the Cuieiras. The sampling has been carried out on vertical profile from 1000 ft up to 12000 ft using a semi-automated sampling package developed at GMD/NOAA and a small aircraft. The analysis uses the MAGICC system (Multiple Analysis of Gases Influence Climate Change) which is installed at the Atmospheric Chemistry Laboratory (LQA) in IPEN (Instituto de Pesquisas Energeticas e Nucleares). The results showed that all gases studied, except H{sub 2} gas, has been following the global trend. At the Para State, for the studied years, the Amazonian Forest performed as small CO{sub 2} sink. To compare Wet and Dry Seasons, subtracted the Ascension concentration values in the period to remove the global influence. So that, in the 2004 and

  1. UNA NUEVA ESPECIE DE COSTUS (COSTACEAE DE LA AMAZONIA COLOMBIANA

    Directory of Open Access Journals (Sweden)

    SALINAS NELSON

    2007-12-01

    Full Text Available Se describe e ilustra Costus fissicalyx N. R. Salinas, Clavijo & Betancur, una especienueva del sudeste de la Amazonia colombiana; además, se presenta información sobresus relaciones taxonómicas, distribución y hábitat. Costus fissicalyx se diferencia delas otras especies del género principalmente por la forma y el tipo de crecimientodel cáliz

  2. Age of depositional and weathering events in Central Amazonia

    Science.gov (United States)

    Sant'Anna, Lucy Gomes; Soares, Emílio Alberto do Amaral; Riccomini, Claudio; Tatumi, Sonia Hatsue; Yee, Marcio

    2017-08-01

    In the last three decades, several studies have been devoted to understanding the role of Late Pleistocene-Holocene climate changes in the Amazonia lowlands environment. However, most of these studies used data obtained from sedimentary deposits (lakes, swamps, and colluvium) located away from the central plain or on the edges of the Amazonia region. This article integrates optically stimulated luminescence and accelerated mass spectrometry 14C ages with sedimentological and geomorphological data obtained during this study or compiled from the literature for fluvial and lacustrine deposits of the central alluvial plain of the Solimões-Amazon River. The age data allow us to present a chronological framework for the Late Pleistocene-Holocene deposits and conclude that (i) the dryness of the LGM in central Amazonia lowlands is recorded by the formation of fluvial terraces and their weathering to pedogenic hematite between 25.3 ka and 17.7 ka; (ii) floodplain deposition was contemporaneous with terrace weathering and occurred in a context of decreased water volume in fluvial channels, lowering of river base level and sea level, and isostatic rebound of the continent; and (iii) lateral and mid-channel fluvial bars in the Solimões-Amazon River have a minimum age of 11.5 ± 1.5 ka, and their deposition responded to increased precipitation at the beginning of the Holocene.

  3. Las palmeras en los valles principales de la Amazonia peruana

    Directory of Open Access Journals (Sweden)

    1992-01-01

    Full Text Available LES PALMIERS DES PRINCIPALES VALLEES DE L’AMAZONIE PERUVIENNE. La distribution géographique des espèces de palmiers de l’Amazonie péruvienne est présentée selon les principales vallées. Pour chaque affluent important est donnée la liste des espèces récoltées, et pour chaque espèce sont réunies les références des échantillons d’herbiers, collecteur(s et numéro de collection, ainsi que les herbiers de dépôt. Se presenta la distribución de las palmeras de la Amazonia en función de los valles principales. Por cada río de mayor importancia, se da la lista de las especies colectadas, las referencias de las muestras botánicas, colector(es y número de colección, y los herbarios de depósito de dichas muestras. PALMS OF THE MAJOR RIVER VALLEYS OF PERUVIAN AMAZONIA. Palm species distribution in Peruvian Amazonia is presented according to the major river valleys. The species collected are listed for each tributary valley. The collection references, collector(s and number of the specimen and the herbaria of deposit are given for each species.

  4. Catalogue of distribution of lizards (Reptilia: Squamata) from the Brazilian Amazonia. I. Dactyloidae, Hoplocercidae, Iguanidae, Leiosauridae, Polychrotidae, Tropiduridae.

    Science.gov (United States)

    Ribeiro-Júnior, Marco A

    2015-07-08

    I present distribution data of all Dactyloidae, Hoplocercidae, Iguanidae, Leiosauridae, Polychrotidae and Tropiduridae lizards known from the Brazilian Amazonia, totaling 40 species-level taxa, belonging to 11 genera. This represents four more species-level taxa than previously reported for these families. Data were based on the direct examination of 41,243 specimens deposited in three North American and eight Brazilian musea, including the main collections harboring Amazonian material. Most species (62.5%) are endemic to the Amazonia; non-endemic species are mainly associated with open dry (semideciduous) forest or open vegetation (savanna) enclaves in Amazonia, with a few exceptions. As a whole, seven taxa are widespread in Amazonia, one is restricted to eastern Amazonia, three to western Amazonia, five to northern Amazonia (either in part of it or widespread in the Guiana region), two to northwestern Amazonia, one to southern Amazonia, nine to southwestern Amazonia, and seven to the southern peripheral portion of Amazonia. Five species have unique distributions and five species have a distribution that is congruent with one of the areas of endemism (AE) recognized for other organisms (birds and primates). The first herpetological gazetteer for the Brazilian Amazonia with about 3,600 georeferenced localities was also produced.

  5. First report of Lecanodiaspis dendrobii Douglas, 1892 (Hemiptera: Lecanodiaspididae) and the associated parasitoid Cephaleta sp. (Hymenoptera: Pteromalidae) in Brazil.

    Science.gov (United States)

    Marsaro Júnior, A L; Peronti, A L B G; Costa, V A; Morais, E G F; Pereira, P R V S

    2016-02-01

    Lecanodiaspis dendrobii Douglas, 1892 (Hemiptera: Coccoidea: Lecanodiaspididae) and the associated parasitoid Cephaleta sp. (Hymenoptera: Pteromalidae) are reported for the first time in Brazil. Specimens of this scale insect were collected on branches and stems of Acacia mangium Willd., Leucaena leucocephala (Lam.) de Wit (Fabaceae), Morus nigra L. (Moraceae), Citrus reticulata Blanco (Rutaceae), Tectona grandis L. f. (Verbenaceae), Anacardium occidentale (Anacardiaceae), Annona squamosa L. and Xylopia aromatica (Lam.) Mart. (Annonaceae), in three municipalities of the Roraima state. All plants here mentioned are recorded for the first time as a host for L. dendrobii. Morphological characters of L. dendrobii and symptoms presented by the host plants infested by this pest are included in this work.

  6. New Odostomia species (Gastropoda, Heterobranchia, Pyramidellidae) from the Miocene Pebas Formation of Western Amazonia (Peru, Colombia)

    NARCIS (Netherlands)

    Aartsen, van J.J.; Wesselingh, F.P.

    2000-01-01

    Odostomia nuttalli spec. nov. and O. coluhensis spec. nov. are described from the Miocene Pebas Formation of Peruvian and Columbian Amazonia. A third pyramidellid snail is also diagnosed. These species are indicators for marine influence in the late Middle to early Late Miocence of Western Amazonia.

  7. Dietary practices and nutritional status of 0-24-month-old children from Brazilian Amazonia.

    Science.gov (United States)

    Castro, T G; Baraldi, L G; Muniz, P T; Cardoso, M A

    2009-12-01

    To assess the nutritional status and dietary practices of 0-24-month-old children living in Brazilian Amazonia. Cross-sectional study. Information on children's dietary intakes was obtained from diet history data. Weight and length were measured for anthropometric evaluation. Fe status was assessed using fasting venous blood samples; Hb, serum ferritin and soluble transferrin receptor concentrations were measured. The towns of Assis Brasil and Acrelândia in the state of Acre, north-west Brazil. A total of sixty-nine randomly selected 0-24-month-old children. Of these children, 40.3 % were anaemic, 63.1 % were Fe-deficient, 28.1 % had Fe-deficiency anaemia and 11.6 % were stunted. Breast-feeding was initiated by 97.1 % of mothers, followed by early feeding with complementary foods. The dietary pattern reflected a high intake of carbohydrate-rich foods and cow's milk, with irregular intakes of fruit, vegetables and meat. All infants and 92.3 % of toddlers were at risk of inadequate Fe intakes. Fe from animal foods contributed on average 0.5 % and 14.3 % to total dietary Fe intake among infants and toddlers, respectively. Poor nutritional status and inadequate feeding practices in this study population reinforce the importance of exclusive breast-feeding during the first 6 months of life. Greater emphasis is required to improve the bioavailability of dietary Fe during complementary feeding practices.

  8. Environmental Costs of Government-Sponsored Agrarian Settlements in Brazilian Amazonia.

    Science.gov (United States)

    Schneider, Maurício; Peres, Carlos A

    2015-01-01

    Brazil has presided over the most comprehensive agrarian reform frontier colonization program on Earth, in which ~1.2 million settlers have been translocated by successive governments since the 1970's, mostly into forested hinterlands of Brazilian Amazonia. These settlements encompass 5.3% of this ~5 million km2 region, but have contributed with 13.5% of all land conversion into agropastoral land uses. The Brazilian Federal Agrarian Agency (INCRA) has repeatedly claimed that deforestation in these areas largely predates the sanctioned arrival of new settlers. Here, we quantify rates of natural vegetation conversion across 1911 agrarian settlements allocated to 568 Amazonian counties and compare fire incidence and deforestation rates before and after the official occupation of settlements by migrant farmers. The timing and spatial distribution of deforestation and fires in our analysis provides irrefutable chronological and spatially explicit evidence of agropastoral conversion both inside and immediately outside agrarian settlements over the last decade. Deforestation rates are strongly related to local human population density and road access to regional markets. Agrarian settlements consistently accelerated rates of deforestation and fires, compared to neighboring areas outside settlements, but within the same counties. Relocated smallholders allocated to forest areas undoubtedly operate as pivotal agents of deforestation, and most of the forest clearance occurs in the aftermath of government-induced migration.

  9. Environmental changes in the western Amazonia: morphological framework, geochemistry, palynology and radiocarbon dating data

    International Nuclear Information System (INIS)

    Horbe, Adriana M.C.; Behling, Hermann; Nogueira, Afonso C.R.; Mapes, Russell

    2011-01-01

    The sediments from the Coari lake, a 'terra firme' lake sculpted into Plio-Pleistocene deposits, and the Acara lake, a flooding-type lake developed on Quaternary sediments in the flood plain of the mid-Solimoes river, in the western Amazonia, Brazil, were studied to investigate the environmental condition of their developing. This study includes mineral composition, geochemistry, Pb isotope, palinology, radiocarbon-age and morphological framework of the lakes obtained from SRTM satellite images. The geological and the environmental conditions in the two lakes are highly variable and suggest that their evolution reflect autogenic processes under humid rain forest condition. Although kaolinite, quartz, muscovite, illite, and smectite are the main minerals in both lakes, the geochemistry indicates distinct source, the Acara lake sediments have higher concentrations of Al 2 O 3 , Fe 2 O 3 , Fe O, Ca O, K 2 O, Mg O, Na 2 O, P 2 O 5 , Ba, V, Cu, Ni, Zn, Pb, Sr, Li, Y and La and have more radiogenic Pb than the Coari lake sediments. The radiocarbon ages suggest that at 10160 yr BP the Coari lake started to be developed due to avulsion of the Solimoes river, and the Acara lake was formed by the meander abandonment of Solimoes river retaining its grass dominated shore at ca. 3710 yr BP. (author)

  10. Environmental Costs of Government-Sponsored Agrarian Settlements in Brazilian Amazonia

    Science.gov (United States)

    2015-01-01

    Brazil has presided over the most comprehensive agrarian reform frontier colonization program on Earth, in which ~1.2 million settlers have been translocated by successive governments since the 1970’s, mostly into forested hinterlands of Brazilian Amazonia. These settlements encompass 5.3% of this ~5 million km2 region, but have contributed with 13.5% of all land conversion into agropastoral land uses. The Brazilian Federal Agrarian Agency (INCRA) has repeatedly claimed that deforestation in these areas largely predates the sanctioned arrival of new settlers. Here, we quantify rates of natural vegetation conversion across 1911 agrarian settlements allocated to 568 Amazonian counties and compare fire incidence and deforestation rates before and after the official occupation of settlements by migrant farmers. The timing and spatial distribution of deforestation and fires in our analysis provides irrefutable chronological and spatially explicit evidence of agropastoral conversion both inside and immediately outside agrarian settlements over the last decade. Deforestation rates are strongly related to local human population density and road access to regional markets. Agrarian settlements consistently accelerated rates of deforestation and fires, compared to neighboring areas outside settlements, but within the same counties. Relocated smallholders allocated to forest areas undoubtedly operate as pivotal agents of deforestation, and most of the forest clearance occurs in the aftermath of government-induced migration. PMID:26247467

  11. Seasonal dynamics of arbuscular mycorrhizal fungi in plants of Theobroma grandiflorum Schum and Paullinia cupana Mart. of aN agroforestry system in Central Amazonia, Amazonas State, Brazil Dinâmica sazonal de fungos micorrízicos arbusculares em plantas de Theobroma grandiflorum Schum e Paullinia cupana Mart. de um sistema agroflorestal na Amazônia Central, Amazonas, Brasil

    Directory of Open Access Journals (Sweden)

    Arlem Nascimento de Oliveira

    2005-09-01

    Full Text Available The seasonal dynamics of Arbuscular Mycorrhizal Fungi (AMF was investigated in the rhizosphere of two fruit species in a terra firme (upland ecosystem in Central Amazonia. Two host species (Theobroma grandiflorum and Paullinia cupana and nine sampling months (August, September and December/1998, February, April, May and December/1999, February and May/2000 were studied in a completely randomized design, with five replications, set in a 2 x 9 factorial experiment. Soil (0-20 cm depth and root samples were collected between August 1998 and May 2000. The mean percent colonization of AMF for both species reached maximal values in February and May 2000 (rainy season. In April and May 1999, February and May 2000 (rainy season the highest AMF spore numbers were registered. The pluvial precipitation was significantly positively correlated with AMF number spores for both fruit species, and significant positive correlation only with AMF colonization of P. cupana. Soil moisture content was positively correlated with colonization and spore numbers of AMF for both species evaluated. AMF colonization and AMF spore numbers of T. grandiflorum were positively correlated with soil Mg and K concentrations. AMF spore numbers of T. grandiflorum were also negatively correlated with effective cation exchange capacity (ECEC. AMF colonization and AMF spore numbers in the rhizosphere of P. cupana were positively correlated with pH and Mn concentrations. AMF colonization was also positively correlated with AMF spore numbers for both species evaluated. In conclusion, this study showed that AMF colonization and sporulation are seasonal and dependent on host plant species, pluvial precipitation, soil moisture content and soil chemistry in Central Amazonia conditions.A dinâmica sazonal de fungos micorrízicos arbusculares (FMA foi investigada na rizosfera de duas espécies frutíferas em um ecossistema de terra firme na Amazônia Central. Adotou-se o delineamento

  12. O foco brasileiro de oncocercose: novas observações feitas nas áreas dos rios Mucajaí e Catrimâni, Território de Roraima The brazilian focus of onchocerciasis: new observations in areas of the Mucajaí and Catrimâni, Territory of Roraima

    Directory of Open Access Journals (Sweden)

    Mário Augusto Pinto de Moraes

    1986-03-01

    âni Rivers (Territory of Roraima has failed to show any alteration in the local pattern of the disease. Infact, after a decade from the first surveys in these areas located at the periphery of the Yanomami focus, the prevalence and the intensity of infection have not experienced a significant change. Considering only the residents in the villages inside the surveyed areas, the prevalence varied from zero in the neighbourhood of the Catrimâni mission to 3.1 per cent near the Mucajai mission. Had there been a competent vector of Onchocerca volvulus in the region higher rates might be expected due to the Yanomami custom of periodic visits among the groups of the tribe. In some of these visits, numbers of highly infected Indians from the central and mountainous part of the Yanomami territory - where more than 90 per cent of the adults have onchocerciasis - come to the villages in the lowland area, attracted by the facilities offered by the mission posts. As the visitors stay in the host villages for several days or weeks, the residents could become exposed to the disease. Simulium oyapockense s.l., a man-biting species of black fly, widely distributed in Northern Brazil, is the only possible vector of O. volvulus in the investigated areas, on the grounds of its local abundance. However, it must be a poor vector (as has already been demonstrated for Mansonella ozzardi, since the prevalence rates in the lower part of the Yanomami territory have not changed for the past ten years, in spite of the constant presence of infected Indians visiting the villages. In order to explain the much higher prevalence in the central part of the Indian territory, we have to admit the presence there of another vector, extremely efficient, whose habits would be linked to the montainous region of the border between Brazil and Venezuela.

  13. Social impacts of Brazil's Tucurui Dam

    International Nuclear Information System (INIS)

    Fearnside, P.M.

    1999-01-01

    The Tucurui Dam, which blocked the Tocantins River in 1984 in Brazil's eastern Amazonian state of Para, is a continuing source of controversy. Most benefits of the power go to aluminum smelting companies, where only a tiny amount of employment is generated. Often presented by authorities as a model for hydroelectric development because of the substantial power that it produces, the project's social and environmental impacts are also substantial. Examination of Tucurui reveals a systematic overestimation of benefits and underestimation of impacts as presented by authorities. Tucurui offers many as-yet unlearned lessons for hydroelectric development in Amazonia

  14. Extreme seasonal droughts and floods in Amazonia: causes, trends and impacts

    Science.gov (United States)

    Marengo, J. A.

    2015-12-01

    J. A. Marengo * and J. C. Espinoza** * Centro Nacional de Monitoramento e Alerta de Desastres Naturais, Ministério da Ciência, Tecnologia e Inovação, Sao Paulo, Brazil ** Subdirección de Ciencias de la Atmósfera e Hidrósfera (SCAH), Instituto Geofísico del Perú, Lima, Peru This paper reviews recent progress in the study and understanding of extreme seasonal events in the Amazon region, focusing on drought and floods. The review includes a history of droughts and floods in the past, in the present and some discussions on future extremes in the context of climate change and its impacts on the Amazon region. Several extreme hydrological events, some of them characterized as 'once in a century', have been reported in the Amazon region during the last decade. While abundant rainfall in various sectors of the basin has determined extreme floods along the river's main stem in 1953, 1989, 1999, 2009, 2012-2015, deficient rainfall in 1912, 1926, 1963, 1980, 1983, 1995, 1997, 1998, 2005 and 2010 has caused anomalously low river levels, and an increase in the risk and number of fires in the region, with consequences for humans. This is consistent with changes in the variability of the hydrometeorology of the basin and suggests that extreme hydrological events have been more frequent in the last two decades. Some of these intense/reduced rainfalls and subsequent floods/droughts were associated (but not exclusively) with La Niña/El Niño events. In addition, moisture transport anomalies from the tropical Atlantic into Amazonia, and from northern to southern Amazonia alter the water cycle in the region year-to-year. We also assess the impacts of such extremes on natural and human systems in the region, considering ecological, economic and societal impacts in urban and rural areas, particularly during the recent decades. In the context of the future climate change, studies show a large range of uncertainty, but suggest that drought might intensify through the 21st

  15. Epidemiology of Disappearing Plasmodium vivax Malaria: A Case Study in Rural Amazonia

    Science.gov (United States)

    Lima, Nathália F.; Batista, Camilla L.; Bastos, Melissa da Silva; Nicolete, Vanessa C.; Fontoura, Pablo S.; Gonçalves, Raquel M.; Viana, Susana Ariane S.; Menezes, Maria José; Scopel, Kézia Katiani G.; Cavasini, Carlos E.; Malafronte, Rosely dos Santos; da Silva-Nunes, Mônica; Vinetz, Joseph M.; Castro, Márcia C.; Ferreira, Marcelo U.

    2014-01-01

    Background New frontier settlements across the Amazon Basin pose a major challenge for malaria elimination in Brazil. Here we describe the epidemiology of malaria during the early phases of occupation of farming settlements in Remansinho area, Brazilian Amazonia. We examine the relative contribution of low-density and asymptomatic parasitemias to the overall Plasmodium vivax burden over a period of declining transmission and discuss potential hurdles for malaria elimination in Remansinho and similar settings. Methods Eight community-wide cross-sectional surveys, involving 584 subjects, were carried out in Remansinho over 3 years and complemented by active and passive surveillance of febrile illnesses between the surveys. We used quantitative PCR to detect low-density asexual parasitemias and gametocytemias missed by conventional microscopy. Mixed-effects multiple logistic regression models were used to characterize independent risk factors for P. vivax infection and disease. Principal Findings/Conclusions P. vivax prevalence decreased from 23.8% (March–April 2010) to 3.0% (April–May 2013), with no P. falciparum infections diagnosed after March–April 2011. Although migrants from malaria-free areas were at increased risk of malaria, their odds of having P. vivax infection and disease decreased by 2–3% with each year of residence in Amazonia. Several findings indicate that low-density and asymptomatic P. vivax parasitemias may complicate residual malaria elimination in Remansinho: (a) the proportion of subpatent infections (i.e. missed by microscopy) increased from 43.8% to 73.1% as P. vivax transmission declined; (b) most (56.6%) P. vivax infections were asymptomatic and 32.8% of them were both subpatent and asymptomatic; (c) asymptomatic parasite carriers accounted for 54.4% of the total P. vivax biomass in the host population; (d) over 90% subpatent and asymptomatic P. vivax had PCR-detectable gametocytemias; and (e) few (17.0%) asymptomatic and subpatent P

  16. Prevalência de excesso de peso e fatores associados em adolescentes de escolas privadas de região urbana na Amazônia Prevalencia de exceso de peso y factores asociados en adolescentes de escuelas privadas de región urbana en Amazonia Prevalence of excess weight and associated factors in adolescents of private schools of an Amazonic urban area, Brazil

    Directory of Open Access Journals (Sweden)

    Laércio M. Silva Júnior

    2012-06-01

    informaciones respecto a sexo, edad, clase socioeconómica, escolaridad de los padres, número de moradores en el domicilio, número de hermanos, actividad física, tiempo gasto asistiendo a la televisión y tiempo de uso de computadora. Los factores asociados al exceso de peso fueron identificados mediante regresión múltiple de Poisson y el uso de eliminación retrógrada para la selección de las variables del modelo múltiple. RESULTADOS: La prevalencia de exceso de peso fue de 29,5%. El sexo masculino mostró mayor prevalencia (33,2% en comparación al femenino (26,4%. Respecto a la edad, la prevalencia fue superior a los 14 años (40% en ambos sexos. En el análisis múltiple, ajustado por edad y sexo, el uso de computadora por más que dos horas diarias y el sedentarismo se asociaron al exceso de peso. CONCLUSIONES: El exceso de peso se presenta como un serio problema de Salud Pública en escolares de la secundaria de instituciones privadas de Rio Branco, Acre (Brasil. Se sugiere la promoción de la actividad física y la reducción en el tiempo de uso de computadora para la disminución del exceso de peso.OBJECTIVE: To assess the prevalence and factors associated with excess weight among high school students. METHODS: Cross-sectional study with 741 adolescents from private schools in Rio Branco, Acre, Northern Brazil. The weight and height were prospectively measured in order to calculate the body mass index. Overweight was defined according to World Health Organization references in 2007. The following variables were collected: gender, age, socioeconomic status, parental education, number of household members and siblings, physical activity, time watching TV and computer time. Factors associated with excess weight were identified by multiple Poisson regression using the backward elimination procedure for variable selection. RESULTS: The prevalence of overweight was 29.5%. Males showed righer prevalence (33.2% compared with females (26.4%. As for age, the prevalence

  17. Eficiencia reproductiva de diferentes genotipos bovinos en la Amazonia Ecuatoriana

    OpenAIRE

    Ortiz Naveda, N. R.; Castro Guamán, W. E.; Marin, P. R.; Universidad de Cuenca; Dirección de Investigación de la Universidad de Cuenca; DIUC

    2015-01-01

    Los problemas reproductivos en el centro de la Amazonia Ecuatoriana, están condicionados por un sin número de factores, que directa e indirectamente conspiran para mejorar los parámetros productivos de la zona. Las condiciones ambientales, el manejo, la falta de energía en la dieta, la salud, la infraestructura y los genotipos utilizados influyen para no lograr una eficiente reproducción Lopez et al., 2014). El anestro posparto es el principal factor que afecta negativamente el desempeño repr...

  18. Ozone concentrations in the Brazilian Amazonia during BASE-A

    International Nuclear Information System (INIS)

    Setzer, A.W.; Kirchhoff, V.W.J.H.; Pereira, M.C.

    1991-01-01

    During the Biomass Burning Airborne and Spaceborne Experiment--Amazonia, thermal images of fires were made with the Advanced Very High Resolution Radiometer (AVHRR) on board meteorological NOAA series satellites. The results of ozone measurements made on board the Brazilian Institute for Space Research (INPE) airplane during September of 1989 are presented and analyzed in relation to the temporal and geographical location of fires detected before and during the sampling. Results show that on a synoptic scale, concentrations of ozone rise sharply in regions of more intense burning

  19. Ocorrência de Passalora bougainvilleae (Muntañola) Castañeda & Braun associado à Bougainvillea spectabilis Willd. em Boa Vista, Roraima

    OpenAIRE

    Nechet,Kátia de Lima; Halfeld-Vieira,Bernardo A.

    2008-01-01

    O fungo Passalora bougainvilleae é relatado, pela primeira vez, na região de Boa Vista, Roraima, associado a manchas foliares na planta ornamental Bougainvillea spectabilis. As características do fungo são conidióforos agregados em fascículos, emergindo de um estroma subcuticular na face abaxial de lesões velhas. Os conidióforos são lisos, retos, de coloração marrom, não ramificados, maioria asseptados, medindo de 26-57µm x 4µm. Células conidiogênicas terminais de proliferação simpodial com c...

  20. Repot of Passalora bougainvilleae (Muntañola) Castañeda & Braun associated with Bougainvillea spectablis Willd. in Boa Vista, Roraima

    OpenAIRE

    Nechet, Kátia de Lima; Halfeld-Vieira, Bernardo A.

    2008-01-01

    O fungo Passalora bougainvilleae é relatado, pela primeira vez, na região de Boa Vista, Roraima, associado a manchas foliares na planta ornamental Bougainvillea spectabilis. As características do fungo são conidióforos agregados em fascículos, emergindo de um estroma subcuticular na face abaxial de lesões velhas. Os conidióforos são lisos, retos, de coloração marrom, não ramificados, maioria asseptados, medindo de 26-57µm x 4µm. Células conidiogênicas terminais de proliferação simpodial com c...

  1. Description of Neblinichthys brevibracchium and N. echinasus from the upper Mazaruni River, Guyana (Siluriformes: Loricariidae, and recognition of N. roraima and N. yaravi as distinct species

    Directory of Open Access Journals (Sweden)

    Donald C. Taphorn

    Full Text Available Neblinichthys brevibracchium and N. echinasus are new sympatric species from upland tributaries of the Mazaruni River (Essequibo River basin of Guyana. These two new species are the first Neblinichthys reported from Guyana. Adult males of both new species have short pectoral-fin spines and several series of hypertrophied odontodes covering the entire dorsal surface and along the entire edge of the snout. They are distinguished from each other by dorsal-fin base length/standard length (18.1-22.8% in N. brevibracchium vs. 24.3-27.0% in N. echinasus, dorsal-anal distance/SL (13.7-18.3% in N. brevibracchium vs. 11.9-12.5% in N. echinasus, by having the snout decreasing in steep arc just anterior to eyes and then flattening in area anterior of nares in N. brevibracchium vs. the snout tapering shallowly and continuously from eyes to snout tip in N. echinasus; and by having the adpressed dorsal fin reaching the anterior preadipose plate in N. brevibracchium (vs. not reaching anterior preadipose plate in N. echinasus. They are distinguished from all congeners by lacking odontodes on the opercle (vs. odontodes present; and by completely lacking an iris operculum (vs. congeners with small iris operculum present or at least dorsal portion of iris flat instead of rounded. Neblinichthys echinasus and N. brevibracchium differ from all congeners by having a spotted or vermiculated pigment pattern on the abdomen (vs. abdomen plain; in N. echinasus the abdomen is darkly pigmented with bold white spots and in Neblinichthys brevibracchium the abdomen is light-colored with gray spots and vermiculations. Neblinichthys brevibracchium and N. echinasus differ from N. roraima by having one to two preadipose plates (vs. four or more. New observations revealed Neblinichthys roraima and N. yaravi to be distinct, with N. roraima having four or more preadipose plates and N. yaravi having one or two. Both are present in the upper río Caroní, an Orinoco tributary that drains

  2. Ostracods biostratigraphy of the Oligocene-Miocene carbonate platform in the Northeastern Amazonia coast and its correlation with the Caribbean region

    Science.gov (United States)

    Nogueira, Anna Andressa Evangelista; Nogueira, Afonso César Rodrigues

    2017-12-01

    Oligocene-Miocene ostracods biozones are proposed for the ∼65 m-thick platform carbonate succession exposed in the Northeastern Amazonia coast, Brazil. Previous biostratigraphic studies based on planktonic foraminifera, nannofossils and palynomorphs are poorly age constrained and have hindered the correlation with other units of the Atlantic Equatorial margin. Tectonic stability of the Northeastern Amazonia coast during Neogene, associated with reduced riverine inflow and continuous sea level rise, allowed the establishment of lagoon/mangroves, tidal channel and shallow platform settings favoring massive proliferation of benthic ostracods. The recurrence of these depositional systems along of entire Oligocene-Miocene succession contributed mainly for the preservation of typical assemblages of lagoonal ostracods. Among thirty-two ostracods genera identified, the most of them are generally polyhalines associated with a mesohaline genus as Perissocytheridea. Rare ostracods genera typical of offshore zone indicate limited oceanic connection with lagoon. Additionally, the rare presence of Cyprideis indicates a relatively stable salinity degree suggesting change in the lagoon dynamic until estuarine conditions. The ostracods comprise more than 100 species, ranging from Upper Oligocene to Lower Miocene with five index species correspondent to a single zone called the Cytherella stainforthi Zone that was subdivided in four sub-biozones: 1) Jugosocythereis pannosa, 2) Quadracythere brachypygaia, 3) Triebelina crumena and 4) Neocaudites macertus. This new zonation was calibrated with the Blow's and Wade's planktonic foraminifers zones (N.3 to N.7 zones corresponding to O6 to M4b of Wade) and with van den Bold's zonation in the Neogene Caribbean region. Ostracod assemblages described here provide an excellent biostragraphic framework for local, intrabasinal and regional correlation for the Oligocene-Miocene deposits of the Northeastern Amazonia coast and Caribbean regions

  3. The expansion of intensive agriculture and ranching in Brazilian Amazonia

    Science.gov (United States)

    Walker, Robert; DeFries, Ruth; del Carmen Vera-Diaz, Maria; Shimabukuro, Yosio; Venturieri, Adriano

    Agriculture in Amazonia has often provoked controversy, given the tremendous ecological value of the region's environment. First with ranching, and now with the soybean boom, tractors and cattle have marched across lands that for millennia supported only closed moist forest, resident ecosystems, and dispersed indigenous peoples. The present chapter considers this expansion, focusing on the Brazilian portion of the basin. Its premise is that effective Amazonian policy must be grounded on an understanding of the region's agriculture. The chapter pursues its objectives by first addressing the development initiatives that created the preconditions for Amazonia's current agricultural economy. The region is remote and has therefore required sustained government intervention to release its potential. The policy discussion is followed by descriptions of cattle ranching and soy farming. For each, market settings and trajectories of expansion are presented. Although these sectoral descriptions are data rich, they do not provide a conceptual framework for analyzing the environmental impacts of evolving market conditions. To accomplish this, the chapter invokes the classical land use model of von Thünen to explain Amazonian land cover dynamics in relation to soy-cattle linkages. It addresses these dynamics with remote sensing data from Mato Grosso, Pará, and Rondônia, and then discusses scenarios of agricultural advances on the forest. Conclusions follow, considering possible policy responses to deforestation, and the social context of agricultural intensification, with special attention to the issues of land tenure security and distributional equity.

  4. Vegetative development of cultivars of palm oil from 14 to 34 months of age in ecosystems Roraima = Desenvolvimento vegetativo de cultivares de palma de óleo dos 14 aos 34 meses de idade em ecossistemas de Roraima

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    Francisco Clemilto da Silva Maciel

    2013-12-01

    Full Text Available The aim of this study was to evaluate the vegetative development of cultivars oil palm Elaeis guineensis Jacq from 14 to 34 months of age in the field in two ecosystems of Roraima. Two experiments were conducted, one in another area of savanna and forest area changes in the assessment of BRS C-2528, C-3701 and BRS BRS C-2301, in experimental design of randomized blocks with six replications. 18 reviews were conducted monthly from August 2008 to April 2010, the number of sheets issued, four leaf length (cm and girth circumference (cm. Analyses of variance individual and joint. For the statistical analysis of the characteristics evaluated test was used Scott-Knott at 5% probability. By comparing the averages of the characteristics evaluated in two environments, we found that, at 34 months old, the forest ecosystem plants had a higher number of leaves, leaf length greater than 4 and greater girth circumference, differing significantly the results obtained in the savanna ecosystem. In forest area changes, independent of cultivar evaluated, plants showed, 3.0 leaves emitted / month, four leaf growth of 8.9 cm / month and girth circumference of 9.6 cm / month, while in savanna, issued 2.5 leaves / month, 4 leaf length of 7.5 cm / month and girth circumference of 6.1 cm / month. It is concluded that changes in forest environment, cultivars have vegetative growth higher than in the environment of savanna. = Objetivou-se com este trabalho avaliar o desenvolvimento vegetativo de cultivares de palma de óleo Elaeis guineensis Jacq dos 14 aos 34 meses de idade no campo, em dois ecossistemas de Roraima. Foram conduzidos dois experimentos, sendo um em área de savana e outro em área de floresta alterada com a avaliação das cultivares BRS C-2528, BRS C-3701 e BRS C-2301, em delineamento experimental de blocos ao acaso com seis repetições. Foram realizadas 18 avaliações mensais, no período de agosto de 2008 a abril de 2010, quanto ao número de folhas

  5. Carbono orgânico e biomassa microbiana do solo em plantios de Acacia mangium no Cerrado de Roraima Soil organic carbon and soil microbial biomass in Acacia mangium plantation in the Savanna of Roraima

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    Sara Magda Oliveira Simões

    2010-03-01

    Full Text Available O objetivo do estudo foi avaliar os efeitos de plantios de Acacia mangium, localizados no cerrado em Roraima, sobre o carbono orgânico e biomassa microbiana do solo. Foram realizadas amostragens de solo nas profundidades de 0-20 cm e 20-40 cm em dois plantios de A. mangium com cerca de cinco anos de idade, e em duas áreas de Cerrado nativo consideradas referência. Um dos plantios de A. mangium (localizado na Fazenda Cigolina correspondeu a um plantio homogêneo (espa��amento de 3,6 m entre linhas e 2,0 m entre plantas enquanto que o outro (localizado no Campo Experimental Água Boa - CEAB correspondeu a um plantio em faixas com duas linhas de plantio (espaçamento de 6 m entre linhas, 2,5 m entre plantas e cerca de 30 m entre faixas. As amostras de solo foram analisadas quanto ao carbono orgânico, carbono da biomassa microbiana, respiração basal do solo e quociente metabólico, além de atributos químicos de fertilidade. Foi verificado que os plantios de A. mangium não proporcionaram aumentos significativos do carbono orgânico do solo em comparação às áreas de referência. Entretanto, na média geral, esses plantios proporcionaram aumento do carbono da biomassa microbiana do solo e redução do quociente metabólico, indicando a possibilidade de acúmulo de carbono orgânico no solo em longo prazo. Também foi observado que, em comparação ao plantio da fazenda Cigolina e às áreas de referência, o carbono microbiano do solo foi maior e acompanhado de menor quociente metabólico no plantio de A. mangium no CEAB, mostrando que a estrutura de plantio exerceu influência sobre a biomassa microbiana do solo.The aim of this study was to evaluate the effects of Acacia mangium plantation in the Roraima's Savanna, on soil organic carbon and soil microbial biomass. Soil samplings were collected on the depths of 0-20 cm and 20-40 cm in two Acacia mangium plantation sites, about five years old, and in two sites of native savanna as

  6. Nuevas especies de Axonopus (Poaceae: Panicoideae: Paniceae de la Amazonia Colombiana

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    Giraldo Cañas Diego

    1998-11-01

    Full Text Available Two new species of Axonopus, A. morronei (series Axonopus and A. zuloagae (series Barbigen are described. The new species are known only from the savannas and sandstone plateau of Colombian northwest Amazonia.Se describen dos nuevas especies de Axonopus, A. morronei y A. zuloagae, de las series Axonopus y Barbigeri, respectivamente. Las nuevas especies son conocidas únicamente de las sabanas y afloramientos rocosos de la Amazonia noroccidental colombiana.

  7. Fish Consumption during Pregnancy, Mercury Transfer, and Birth Weight along the Madeira River Basin in Amazonia

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    Renata S. Leão

    2013-05-01

    Full Text Available Birth weight can be a predictor of maternal health issues related to nutrition and environmental contaminants. Total hair mercury (HHg concentration was studied as an indicator of both fish consumption and methylmercury exposure in mothers (and newborns living in selected low income areas of the Madeira River basin, Amazonia, Brazil. This cohort study (n = 1,433 consisted of traditional riverines (n = 396, riverines who had moved to urban (n = 676 and rural (n = 67 settings, and tin miner settlers (n = 294. Median maternal HHg was significantly different (p = 0.00001 between riverine (12.1 µg·g−1, rural (7.82 µg·g−1, urban (5.4 µg·g−1, and tin miner (4.5 µg·g−1 groups studied. The same trend (of medians was observed for newborns’ HHg which also showed significant differences between riverine (3.0 µg·g−1, rural (2.0 µg·g−1, urban (1.5 µg·g−1, and tin miner (0.8 µg·g−1 groups. The correlation between maternal and newborn HHg was statistically significant in the riverine (r = 0.8952; p = 0.0001, urban (r = 0.6744; p = 0.0001, and rural (r = 0.8416; p = 0.0001 groups but not in the mother-infant pairs in the tin miner group (r = 0.0638; p = 0.2752. Birth weight was significantly different among groups but did not show a pattern consistent with that of fish consumption (and HHg. A multiple regression analysis showed that only family income and gestational age had a significant impact on birth weight. Conclusions: Maternal HHg is an important biomarker of maternal fish consumption and of methylmercury exposure during pregnancy. However, in these Amazonian groups, only maternal education and gestational age seemed to affect birth weight positively.

  8. Meso-scale effects of tropical deforestation in Amazonia: preparatory LBA modelling studies

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    A. J. Dolman

    1999-08-01

    Full Text Available As part of the preparation for the Large-Scale Biosphere Atmosphere Experiment in Amazonia, a meso-scale modelling study was executed to highlight deficiencies in the current understanding of land surface atmosphere interaction at local to sub-continental scales in the dry season. Meso-scale models were run in 1-D and 3-D mode for the area of Rondonia State, Brazil. The important conclusions are that without calibration it is difficult to model the energy partitioning of pasture; modelling that of forest is easier due to the absence of a strong moisture deficit signal. The simulation of the boundary layer above forest is good, above deforested areas (pasture poor. The models' underestimate of the temperature of the boundary layer is likely to be caused by the neglect of the radiative effects of aerosols caused by biomass burning, but other factors such as lack of sufficient entrainment in the model at the mixed layer top may also contribute. The Andes generate patterns of subsidence and gravity waves, the effects of which are felt far into the Rondonian area The results show that the picture presented by GCM modelling studies may need to be balanced by an increased understanding of what happens at the meso-scale. The results are used to identify key measurements for the LBA atmospheric meso-scale campaign needed to improve the model simulations. Similar modelling studies are proposed for the wet season in Rondonia, when convection plays a major role.Key words. Atmospheric composition and structure (aerosols and particles; biosphere-atmosphere interactions · Meterology and atmospheric dynamics (mesoscale meterology

  9. Meso-scale effects of tropical deforestation in Amazonia: preparatory LBA modelling studies

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    A. J. Dolman

    Full Text Available As part of the preparation for the Large-Scale Biosphere Atmosphere Experiment in Amazonia, a meso-scale modelling study was executed to highlight deficiencies in the current understanding of land surface atmosphere interaction at local to sub-continental scales in the dry season. Meso-scale models were run in 1-D and 3-D mode for the area of Rondonia State, Brazil. The important conclusions are that without calibration it is difficult to model the energy partitioning of pasture; modelling that of forest is easier due to the absence of a strong moisture deficit signal. The simulation of the boundary layer above forest is good, above deforested areas (pasture poor. The models' underestimate of the temperature of the boundary layer is likely to be caused by the neglect of the radiative effects of aerosols caused by biomass burning, but other factors such as lack of sufficient entrainment in the model at the mixed layer top may also contribute. The Andes generate patterns of subsidence and gravity waves, the effects of which are felt far into the Rondonian area The results show that the picture presented by GCM modelling studies may need to be balanced by an increased understanding of what happens at the meso-scale. The results are used to identify key measurements for the LBA atmospheric meso-scale campaign needed to improve the model simulations. Similar modelling studies are proposed for the wet season in Rondonia, when convection plays a major role.

    Key words. Atmospheric composition and structure (aerosols and particles; biosphere-atmosphere interactions · Meterology and atmospheric dynamics (mesoscale meterology

  10. GROWTH OF AMAZON NATIVE SPECIES SUBMITTED TO THE PLANTATION IN THE RORAIMA STATE

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    Helio Tonini

    2009-10-01

    Full Text Available An important forest research challenge in the Amazonian is finding forms of reforesting degraded areas with the use of a larger number of native species and identify tropical species commercially attractive adapted to clear-cut areas. This work had as objectives to evaluate the initial growth in diameter and height of six native Amazonian species in a preliminary species trial. The data were obtained from measures of 72 trees 9 years after planting. The selected species for this study were cupiúba (Goupia glabra, cumaru (Dipterix odorata, andiroba (Carapa guianensis, brazil nut (Bertholletia excelsa, pará-pará (Jacaranda copaia and tatajuba (Bagassa guianensis. The cumulative growth curves for diameter and height was obtained by the Chapman – Richards function. In spite of the low age of the stands, it was obtained good fit to the function for the studied species. Pará-pará (Jacaranda copaia, presented best diameter and height growth in all the ages. The diameter mean annual increment analysis showed that, except for the cupiúba (Goupia glabra,  can be expected  increments larger than  2 cm, by appropiate spacings and thinning.

  11. CHLOROCOCCALES DE LA AMAZONIA COLOMBIANA I: Chlorellaceae y Scenedesmaceae

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    ECHENIQUE RICARDO O.

    2004-06-01

    Full Text Available En este trabajo damos a conocer 41 taxones pertenecientes a las familias Chlorellaceaey Scenedesmaceae del orden Chlorococcales (Algae, Cholophyceae hallados entres cuencas de la Amazonia colombiana: Amazonas (Solimões, Putumayo (Içã yCaquetá (Japurá. Del total encontrado, 19 son nuevas citas para Colombia, nueveson nuevos registros para la cuenca en estudio y se propone una nueva entidadtaxonómica Tetraedron triangulare f. major Echenique nova forma. La mayor riquezase encontró en los lagos de inundación del río Amazonas, en particular en el lagoYahuarcaca que presenta amplio desarrollo de macrófitos y los mayores nivelestróficos de la región.

  12. Drug tourism or spiritual healing? Ayahuasca seekers in Amazonia.

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    Winkelman, Michael

    2005-06-01

    This research addresses the question of whether Westerners who seek traditional spiritual medicine known as ayahuasca can be best characterized as "drug tourists" or as people pursuing spiritual and therapeutic opportunities. Participants in an ayahuasca retreat in Amazonia were interviewed regarding their motivations for participation and the benefits they felt that they received. These findings from the interviews were organized to reveal common motivations and benefits. Contrary to the characterization as "drug tourists", the principal motivations can be characterized as: seeking spiritual relations and personal spiritual development; emotional healing; and the development of personal self-awareness, including contact with a sacred nature, God, spirits and plant and natural energies produced by the ayahuasca. The motivation and perceived benefits both point to transpersonal concerns, with the principal perceived benefits involving increased self awareness, insights and access to deeper levels of the self that enhanced personal development and the higher self, providing personal direction in life.

  13. Pervasive Rise of Small-scale Deforestation in Amazonia.

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    Kalamandeen, Michelle; Gloor, Emanuel; Mitchard, Edward; Quincey, Duncan; Ziv, Guy; Spracklen, Dominick; Spracklen, Benedict; Adami, Marcos; Aragão, Luiz E O C; Galbraith, David

    2018-01-25

    Understanding forest loss patterns in Amazonia, the Earth's largest rainforest region, is critical for effective forest conservation and management. Following the most detailed analysis to date, spanning the entire Amazon and extending over a 14-year period (2001-2014), we reveal significant shifts in deforestation dynamics of Amazonian forests. Firstly, hotspots of Amazonian forest loss are moving away from the southern Brazilian Amazon to Peru and Bolivia. Secondly, while the number of new large forest clearings (>50 ha) has declined significantly over time (46%), the number of new small clearings (<1 ha) increased by 34% between 2001-2007 and 2008-2014. Thirdly, we find that small-scale low-density forest loss expanded markedly in geographical extent during 2008-2014. This shift presents an important and alarming new challenge for forest conservation, despite reductions in overall deforestation rates.

  14. Mangrove vegetation in Amazonia: a review of studies from the coast of Pará and Maranhão States, north Brazil Vegetação de manguezais na Amazônia: uma revisão dos estudos da costa dos Estados Pará e Maranhão, norte do Brasil

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    Moirah Paula Machado de Menezes

    2008-01-01

    Full Text Available The present study is a compilation of the literature about vegetation of mangrove forest of the north coast of Brazil. It synthesizes the knowledge about this important ecosystem and lists the currently available literature. The study focuses on the coast of Pará and Maranhão states, which are covered by a continuous belt of mangroves. The mangrove flora comprises six mangrove tree species and several associated species. Mangrove tree height and stem diameter vary as a function of abiotic local stand parameters. Seasonal variation in rainfall and salinity affect the species' phenology and litter fall. Local population use products derived from mangrove plants for different purposes (e.g. fuel; medicinal; rural construction. The increase in the coastal population has given rise to conflicts, which impact on mangrove forest.O presente estudo apresenta uma compilação da literatura sobre a vegetação dos manguezais da costa norte do Brasil, apresentando uma síntese do conhecimento e listando a literatura disponível. O estudo se concentra na costa dos estados do Pará e Maranhão que formam um cinturão contínuo de manguezais . Foram contabilizadas seis espécies arbóreas exclusivas de mangue e várias outras associadas. A altura e o diâmetro das árvores de mangue variam em função de parâmetros abióticos locais. As variações sazonais do regime de chuvas e da salinidade afetam a fenologia das espécies e a produção de serapilheira. A população costeira utiliza a flora do manguezal para diferentes fins (ex: combustível, medicinal, construção rural. O aumento da ocupação costeira inicia um processo de impacto para as florestas de mangue e a disponibilidade de seus recursos.

  15. USOS DE LAS PALMAS EN LA AMAZONIA COLOMBIANA

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    LAURA MESA

    2013-12-01

    Full Text Available Con el fin de obtener un diagnóstico del estado actual de conocimiento sobre usos de las palmas en la Amazonia colombiana, se revisaron las principales fuentes de información. Treinta y seis de las 41 etnias indígenas consideradas tuvieron registros de uso. Se registraron 82 especies de palmas usadas (78% de las potenciales y 165 usos distribuidos en ocho categorías; todos los usos se presentan de manera detallada en un catálogo. Las categorías de uso más importantes fueron: utensilios y herramientas, construcción, y alimentación humana. Las diez especies más importantes fueron Bactris gasipaes, Euterpe precatoria, Mauritia flexuosa, Oenocarpus bataua, Attalea maripa, Oenocarpus minor, Astrocaryum chambira, Iriartea deltoidea, Oenocarpus bacaba y Socratea exorrhiza; la mayoría de ellas también han sido registradas como las más importantes en otras partes del Neotrópico. No se encontró ninguna información sobre usos de palmas para varios grupos indígenas, especialmente para las etnias cocama, letuama, piaroa, pisamira y yurí, para las cuales se requieren investigaciones detalladas. Se concluye que a pesar de los vacíos de información, los resultados muestran que las palmas son un recurso muy importante con un gran potencial, y una pieza fundamental para la seguridad alimentaria y el desarrollo sustentable de la Amazonia colombiana. Sugerimos la inclusión de las especies más importantes en programas de manejo y agroforestales, al igual que la implementación y popularización de técnicas de cosecha no destructivas. Recomendamos además que las investigaciones futuras estén enfocadas en desarrollar estrategias de manejo que garanticen el uso sostenible de todas estas especies útiles.

  16. Avaliação de linhagens de arroz irrigado com tipo de grão para a culinária japonesa para o Estado de Roraima. = Evaluation of irrigated rice strains with grain type for Japanese cuisine in the State of Roraima.

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    Antonio Carlos Centeno Cordeiro

    2010-12-01

    Full Text Available Em Roraima, o cultivo do arroz representa uma das poucas cadeias produtivas efetivamente estabilizadas, com produção suficiente para abastecer o mercado interno e permitir exportação para outros estados. No entanto, as agroindústrias locais comercializam, basicamente, o arroz branco de classe longo-fino. A diversificação de tipos de grãos, como os demandados para a culinária japonesa cria uma oportunidade de verticalização da produção e propicia aumento de renda já que o preço desse produto chega a ser, em média, duas a três vezes superiores ao tipo local. Assim, objetivou-se com este trabalho avaliar o desempenho produtivo e de qualidade de linhagens de arroz irrigado com tipo de grãos para a culinária japonesa, nas condições de cultivo de Roraima. Foram avaliadas, no período de dezembro de 2003 a março de 2004, dez linhagens de arroz irrigadoem delineamento experimental de blocos ao acaso com quatro repetições. Além das características agronômicas foi avaliada aqualidade dos grãos. A linhagem de arroz irrigado CNAi 9903 mostrou-se como a mais adequada em relação à característica de teor de amilose baixo, semelhante à testemunha no teste de cocção, mostrando-se assim, com potencial para uso na culinária japonesa, além boa produtividade e adaptação às condições de cultivo em várzea Roraima. = The cultivation of rice represents one of the few productive chains effectively stabilized in the State of Roraima, with enough production to supply the domestic market and allow export to other states. However the local agribusiness commercializes basically the long-thin class white rice. The diversification of grain types, as the demanded for Japanese cuisine, creates an opportunity for vertical integration of production and provides increased income, since the price of the product reaches an average of two to three times higher than the local type. Thus, the purpose of this study was to evaluate the performance

  17. Evapotranspiration measurements in rainfed and irrigated cropland illustrate trade-offs in land and water management in Southern Amazonia's agricultural frontier

    Science.gov (United States)

    Lathuilliere, M. J.; Dalmagro, H. J.; Black, T. A.; Arruda, P. H. Z. D.; Hawthorne, I.; Couto, E. G.; Johnson, M. S.

    2017-12-01

    Southern Amazonia, Brazil, is home to a rapidly expanding agricultural frontier in which tropical forest and savanna landscapes have been increasingly replaced by agricultural land since the 1990s. One important impact of deforestation is the reduction in water vapour transferred to the atmosphere via evapotranspiration (ET) from rainfed agriculture landscapes compared to natural vegetation, leading to a reduction in regional precipitation recycling. Here, we discuss land and water management choices for future agricultural production in Southern Amazonia and their potential effects on the atmospheric water cycle. We illustrate these choices by presenting ET measurements on an agricultural landscape by eddy covariance (EC) between September 2015 and February 2017. Measurements were made for two fields adjacent to one micrometeorological EC tower: (1) one rainfed field containing a succession of soybean, maize, brachiara and soybean, and (2) one irrigated field with a succession of soybean, rice, beans, and soybean. Over the time period, total ET in the rainfed and irrigated fields was 1266 ± 294 mm and 1415 ± 180 mm, respectively for a total precipitation of 3099 mm. The main difference in ET between the fields was attributed to the application of 118 mm of surface water irrigated for bean production in the irrigated field between June and September 2016. In the rainfed field, soybean ET was 332 ± 82 mm (2015-2016) and 423 ± 99 mm (2016-2017) for 824 mm and 1124 mm of precipitation, respectively. In the irrigated field, soybean ET was 271 ± 38 mm (2015) and 404 ± 60 mm (2016-2017) with supplemental irrigation added in 2015. Our results illustrate how supplemental irrigation can favour early soybean planting while transferring additional water vapour to the atmosphere at levels similar to natural vegetation. We conclude by discussing our results in the context of future land and water trade-offs for agricultural intensification in Brazil's "arc-of-deforestation".

  18. SOILS AND GEOENVIRONMENTS OF THE NATIONAL PARK OF VIRUÁ AND SURROUNDING, RORAIMA: INTEGRATED VISION OF THE LANDSCAPE AND ENVIRONMENTAL SERVICE

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    Bruno Araujo Furtado de Mendonça

    2013-06-01

    Full Text Available http://dx.doi.org/10.5902/198050989287The Viruá National Park (PARNA Viruá occupies 227.011ha, in the region of the low ‘Branco’ river, in Roraima state. This area includes an extensive mosaic of complex seasonally flooded forested and non-forested environments. The present work had as general objective to characterize the pedology aspects and the geo-environmental units of the Park and surroundings, in an integrated vision of the landscape and, additionally, estimate the carbon stocks in the soils and geo-environments. We described and collected 29 soil profiles in the main vegetation types of Campinaranas and Forests of PARNA Viruá and surroundings. The main soil classes are: Espodossolo Humilúvico, Neossolo Quartzarênico, Neossolo Flúvico, Neossolo Litólicos, Latossolo Vermelho-Amarelo, Latossolo Vermelho, Cambissolo Háplico, Cambissolo Flúvico, Gleissolo Háplico and Plintossolo Háplico. The soils present spatial distribution marked by abrupt limits and close association with the vegetation type. We identified three pedo-environments: (1 sandy soils of the Campinaranas; (2 soils associated with the inselbergs and adjacencies; and (3 alluvial soils. We mapped and described 18 geoenvironmental units in PARNA Viruá National Park. The main geo-environments are: i Sandy plains and Paleodunes with grassy and arborous Campinarana on ‘Neossolos Quartzarênicos hidromórficos’ and ‘Espodossolos’; and Floodplains and; ii Terraces with Igapó Forest on sandy hydromorphic soils, occupying 24.6% and 20.1% of the studied area, respectively. In terms of total soil carbon stocks, the geo-environments of the sandy complexes of Campinaranas and associations stand out, with 9450.9 Gg C. The great extension and representativeness of the sandy areas of Campinaranas characterize PARNA Viruá PArk as an important conservation unit for protection Amazonian sandy soil systems. The areas under the domain of ‘Espodossolos’ possess the

  19. Solos da área indígena Yanomami no médio Rio Catrimani, Roraima Soils in the Yanomami indigenous area in the mid-Catrimani River - Roraima

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    Valdinar Ferreira Melo

    2010-04-01

    Full Text Available Em Roraima, a distribuição espacial das populações indígenas identifica um cenário de busca constante de solos capazes de sustentar uma agricultura itinerante. Este trabalho teve como objetivo estabelecer relação entre a compreensão dos solos por parte dos Yanomami da região do médio Catrimani e o Sistema Brasileiro de Classificação de Solos, bem como avaliar o seu tipo de uso em função de análises químicas para diagnóstico da fertilidade do solo. O trabalho foi executado em duas etapas. A primeira consistiu em visitas a oito malocas para estudar os solos. Foram coletadas amostras em trincheiras até 1,50 m de profundidade para análise e classificação dos solos e (em prospecções com o trado nas profundidades de 0-10 a 10-30 cm, em 21 tipos de uso agrícola, e da área de floresta para análises químicas de fertilidade. A segunda fase foi uma oficina, abordando os sistemas de exploração agrícola, com duração de 20 h. Focalizou-se a discussão sobre a compreensão do meio ambiente (Urihi(1 e sistemas de produção agrícolas e sobre a importância do uso correto do conhecimento dos solos. Os solos são denominados pelos Yanomami em função das características morfológicas, pelos teores de matéria orgânica e pela presença de minhocas, e da posição na paisagem - a escolha para agricultura é fundamentada nessas características. As práticas agrícolas consistem da derrubada da mata nativa, queima e plantio das culturas em separado. Os solos descritos na área foram: Argissolo Vermelho-Amarelo (Maxita a uuxi wakë axi, Argissolo Amarelo (Maxita a axi, Latossolo Amarelo (Maxita a axi e Plintossolo (Maxita a axi a maamaxipë. O processo de derruba e queima promove um incremento inicial do teor de Ca e K trocáveis e P assimilável devido à contribuição das cinzas, o que permite a exploração das áreas por um período máximo de três anos.In Roraima, the spatial distribution of indigenous peoples indicates a

  20. Ecofunctional Traits and Biomass Production in Leguminous Tree Species under Fertilization Treatments during Forest Restoration in Amazonia

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    Roberto K. Jaquetti

    2016-04-01

    Full Text Available Background: Choosing the correct species and fertilization treatments is a determining factor in the success of forest restoration. Methods: A field study was conducted in a degraded area near the Balbina hydroelectric dam in Amazonas State (AM, Brazil, to evaluate two hypotheses: (i leguminous tree species exhibit differences in growth, leaf nutrient content, and photosynthetic nutrient use efficiencies; and (ii differences in these characteristics depend on the fertilization treatments to which the species have been subjected. Dipteryx odorata, Inga edulis and Schizolobium amazonicum were subjected to the following treatments: (T1 unfertilized control; (T2 post-planting chemical fertilization; (T3 post-planting organic fertilization and (T4 combined chemical and organic post-planting fertilization. Results: In general, I. edulis had the highest absolute growth rate of biomass under all of the fertilization treatments. I. edulis and S. amazonicum showed the highest growth rates under the T4 treatment. D. odorata showed the greatest responses under the T2 and T4 treatments. Native leguminous trees with higher photosynthetic performance and better nutrient use efficiency exhibited greater growth and biomass production. Conclusion: The results suggest that an adequate balance between leguminous species selection and fertilization will aid in the success of forest restoration in Amazonia.

  1. Caracterização morfométrica da bacia hidrográfica do Igarapé Carrapato, Boa Vista, Roraima

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    Maola Monique Faria

    2017-10-01

    Full Text Available O manejo de bacias hidrográficas baseia-se em um conjunto de técnicas aplicadas com o objetivo de regularizar a vazão dos cursos hídricos, a produção econômica e a proteção ambiental, garantindo a preservação da biodiversidade. O presente estudo tem como objetivo determinar as características morfométricas da bacia hidrográfica do Igarapé Carrapato, Boa Vista/Roraima. Inicialmente foi obtido o Modelo Digital de Elevação, e com base nele a bacia foi delimitada. Posteriormente foram calculados alguns parâmetros morfométricos para o estudo do comportamento hidrológico da bacia. A bacia em estudo, com base na análise dos fatores morfométricos analisados, apresenta baixa susceptibilidade a enchentes.

  2. Cultivo intercalares em fase inicial de desenvolvimento e desempenho produtivo de cultivares de palma de óleo em diferentes ambientes de Roraima

    OpenAIRE

    Antonia Dianaia Oliveira Lopes

    2014-01-01

    A expansão da cultura da palma de óleo nas áreas já desflorestadas da Amazônia legal é reconhecida como uma excelente alternativa para a produção de óleo para fins alimentícios e energéticos. O estado de Roraima apresenta as condições edafoclimáticas adequadas para seu desenvolvimento e introdução na estrutura da agricultura familiar. Objetivou-se com este trabalho desenvolver sistemas de cultivos nas entrelinhas da palma de óleo em área de floresta alterada, durante o período inicial de dese...

  3. INTERCEPTION OF ANIMAL-ORIGIN PRODUCTS AT LAND BORDERS IN BRAZIL

    Directory of Open Access Journals (Sweden)

    Mirela Janice Eidt

    2015-07-01

    Full Text Available Infectious agents and veterinary diseases can be disseminated across borders and contribute to change the country sanitary status. The aim of this study was to identify the main animal products intercepted and seized by the agricultural surveillance units. This paper studied three Agricultural Surveillance Units located at land borders in the North region of Brazil: Assis Brasil and Epitaciolândia (Acre State and Pacaraima (Roraima State, respectively borders with Peru, Bolivia and Venezuela. The main animal products confiscated were dairy products, fish, meat, sausage, veterinary products (drugs, animal food (pet foods and apiculture products. Given the clandestine nature of animal transit and its products in these borders, the possibilities of introduction of infectious agents and diseases must be better evaluated, considering the type of products confiscated, as well as the sanitary status of the countries of origin.

  4. Electric systems failures produced by CG lightning in Eastern Amazonia

    Directory of Open Access Journals (Sweden)

    Ana Paula Paes dos Santos

    2014-12-01

    Full Text Available Operational records of power outages of the electric energy distribution systems in eastern Amazonia presented a large number of events attributed to lightning strikes, during the 2006 to 2009 period. The regional electricity concessionary data were compared to actual lightning observations made by SIPAM's LDN system, over two areas where operational sub systems of transmission lines are installed. Statistical relations were drawn between the monthly lightning occurrence density and the number of power outages of the electric systems for both areas studied. The results showed that, although with some delays between these variables peaks, the number of power disruptions has a tendency to follow the behavior of the lightning occurrence densities variations. The numerical correlations were positive and may be useful to the transmission lines maintenance crews at least for the Belém-Castanhal electricity distribution sub system. Evidence was found, that the SST's over certain areas of the Pacific and Atlantic Oceans, influence convection over the area of interest, and may help to prognosticate the periods of intense electric storms, requiring repair readiness for the regional electric systems.

  5. Optical and geometrical properties of cirrus clouds in Amazonia derived from 1 year of ground-based lidar measurements

    Science.gov (United States)

    Gouveia, Diego A.; Barja, Boris; Barbosa, Henrique M. J.; Seifert, Patric; Baars, Holger; Pauliquevis, Theotonio; Artaxo, Paulo

    2017-03-01

    Cirrus clouds cover a large fraction of tropical latitudes and play an important role in Earth's radiation budget. Their optical properties, altitude, vertical and horizontal coverage control their radiative forcing, and hence detailed cirrus measurements at different geographical locations are of utmost importance. Studies reporting cirrus properties over tropical rain forests like the Amazon, however, are scarce. Studies with satellite profilers do not give information on the diurnal cycle, and the satellite imagers do not report on the cloud vertical structure. At the same time, ground-based lidar studies are restricted to a few case studies. In this paper, we derive the first comprehensive statistics of optical and geometrical properties of upper-tropospheric cirrus clouds in Amazonia. We used 1 year (July 2011 to June 2012) of ground-based lidar atmospheric observations north of Manaus, Brazil. This dataset was processed by an automatic cloud detection and optical properties retrieval algorithm. Upper-tropospheric cirrus clouds were observed more frequently than reported previously for tropical regions. The frequency of occurrence was found to be as high as 88 % during the wet season and not lower than 50 % during the dry season. The diurnal cycle shows a minimum around local noon and maximum during late afternoon, associated with the diurnal cycle of precipitation. The mean values of cirrus cloud top and base heights, cloud thickness, and cloud optical depth were 14.3 ± 1.9 (SD) km, 12.9 ± 2.2 km, 1.4 ± 1.1 km, and 0.25 ± 0.46, respectively. Cirrus clouds were found at temperatures down to -90 °C. Frequently cirrus were observed within the tropical tropopause layer (TTL), which are likely associated to slow mesoscale uplifting or to the remnants of overshooting convection. The vertical distribution was not uniform, and thin and subvisible cirrus occurred more frequently closer to the tropopause. The mean lidar ratio was 23.3 ± 8.0 sr. However, for

  6. Biome-Scale Forest Properties in Amazonia Based on Field and Satellite Observations

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    Liana O. Anderson

    2012-05-01

    Full Text Available Amazonian forests are extremely heterogeneous at different spatial scales. This review intends to present the large-scale patterns of the ecosystem properties of Amazonia, and focuses on two parts of the main components of the net primary production: the long-lived carbon pools (wood and short-lived pools (leaves. First, the focus is on forest biophysical properties, and secondly, on the macro-scale leaf phenological patterns of these forests, looking at field measurements and bringing into discussion the recent findings derived from remote sensing dataset. Finally, I discuss the results of the three major droughts that hit Amazonia in the last 15 years. The panorama that emerges from this review suggests that slow growing forests in central and eastern Amazonia, where soils are poorer, have significantly higher above ground biomass and higher wood density, trees are higher and present lower proportions of large-leaved species than stands in northwest and southwest Amazonia. However, the opposite pattern is observed in relation to forest productivity and dynamism, which is higher in western Amazonia than in central and eastern forests. The spatial patterns on leaf phenology across Amazonia are less marked. Field data from different forest formations showed that new leaf production can be unrelated to climate seasonality, timed with radiation, timed with rainfall and/or river levels. Oppositely, satellite images exhibited a large-scale synchronized peak in new leaf production during the dry season. Satellite data and field measurements bring contrasting results for the 2005 drought. Discussions on data processing and filtering, aerosols effects and a combined analysis with field and satellite images are presented. It is suggested that to improve the understanding of the large-scale patterns on Amazonian forests, integrative analyses that combine new technologies in remote sensing and long-term field ecological data are imperative.

  7. The Roles and Movements of Actors in the Deforestation of Brazilian Amazonia

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    Philip M. Fearnside

    2008-06-01

    Full Text Available Containing the advance of deforestation in Brazilian Amazonia requires understanding the roles and movements of the actors involved. The importance of different actors varies widely among locations within the region, and also evolves at any particular site over the course of frontier establishment and consolidation. Landless migrants have significant roles in clearing the land they occupy and in motivating landholders to clear as a defense against invasion or expropriation. Colonists in official settlements and other small farmers also are responsible for substantial amounts of clearing, but ranchers constitute the largest component of the region's clearing. This group is most responsive to macroeconomic changes affecting such factors as commodity prices, and also receives substantial subsidies. Ulterior motives, such as land speculation and money laundering, also affect this group. Drug trafficking and money laundering represent strong forces in some areas and help spread deforestation where it would be unprofitable based only on the legitimate economy. Goldminers increase the population in distant areas and subsequently enter the ranks of other groups. Work as laborers or debt slaves provides an important entry to the region for poor migrants from northeast Brazil, providing cheap labor to large ranches and a large source of entrants to other groups, such as landless farmers and colonists. Capitalized farmers, including agribusiness for soy production, have tremendous impact in certain areas, such as Mato Grosso. This group responds to commodity markets and provides justification for major infrastructure projects. Landgrabbers, or grileiros, are important in entering public land and beginning the process of deforestation and transfer of land to subsequent groups of actors. These include sawmill owners and loggers, who play an important role in generating funds for clearing by other groups, ranging from landless migrants to large ranchers. They

  8. Late quaternary dynamics in the Madeira river basin, southern Amazonia (Brazil, as revealed by paleomorphological analysis

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    Ericson H. Hayakawa

    2015-03-01

    Full Text Available Ancient drainage systems are being increasingly documented in the Amazon basin and their characterization is crucial for reconstructing fluvial evolution in this area. Fluvial morphologies, including elongate belts, are well preserved along the Madeira River. Digital Elevation Model from the Shuttle Radar Topography Mission favored the detection of these features even where they are covered by dense rainforest. These paleomorphologies are attributed to the shifting position of past tributaries of the Madeira River through avulsions. These radial paleodrainage networks produced fan-shaped morphologies that resemble distributary megafans. Distinguishing avulsive tributary systems from distributary megafans in the sedimentary record is challenging. Madeira´s paleodrainage reveals the superposition of tributary channels formed by multiple avulsions within a given time period, rather than downstream bifurcation of coexisting channels. Channel avulsion in this Amazonian area during the late Quaternary is related to tectonics due to features as: (i straight lineaments coincident with fault directions; (ii northeastward tilting of the terrain with Quaternary strata; and (iii several drainage anomalies, including frequent orthogonal drainage inflections. These characteristics altogether lead to propose that the radial paleodrainage present at the Madeira River margin results from successive avulsions of tributary channels over time due to tectonics.

  9. Water balance, nutrient and carbon export from a heath forest catchment in central Amazonia, Brazil

    NARCIS (Netherlands)

    Zanchi, F. .B.; Waterloo, M.J.; Tapia, A.P.; Alvarado Barrientos, M.S.; Bolson, M.A.; Luizao, F.J.; Manzi, A.O.; Dolman, A.J.

    2015-01-01

    Carbon storage values in the Amazon basin have been studied through different approaches in the last decades in order to clarify whether the rainforest ecosystem is likely to act as a sink or source for carbon in the near future. This water balance, dissolved organic carbon (DOC) and nutrient export

  10. Spatial heterogeneity of malaria in Indian reserves of Southwestern Amazonia, Brazil

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    Santos Ricardo

    2008-11-01

    Full Text Available Abstract Background Malaria constitutes a major cause of morbidity in the Brazilian Amazon where an estimated 6 million people are considered at high risk of transmission. Indigenous peoples in the Amazon are particularly vulnerable to potentially epidemic disease such as malaria; notwithstanding, very little is known about the epidemiology of malaria in Indian reservations of the region. The aim of this paper is to present a spatial analysis of malaria cases over a four-year time period (2003–2006 among indigenous peoples of the Brazilian State of Rondônia, southwestern Amazon, by using passive morbidity data (results from Giemsa-stained thick blood smears gathered from the National Malaria Epidemiologic Surveillance System databank. Results A total of 4,160 cases of malaria were recorded in 14 Indian reserves in the State of Rondônia between 2003 and 2006. In six reservations no cases of malaria were reported in the period. Overall, P. vivax accounted for 76.18 of malaria cases reported in the indigenous population of Rondônia. The P. vivax/P. falciparum ratio for the period was 3.78. Two reserves accounted for over half of the cases reported for the total indigenous population in the period – Roosevelt and Pacaas Novas – with a total of 1,646 (39.57% and 1,145 (27.52% cases, respectively. Kernel mapping of malaria mean Annual Parasite Index – API according to indigenous reserves and environmental zones revealed a heterogeneous pattern of disease distribution, with one clear area of high risk of transmission comprising reservations of west Rondônia along the Guaporé-Madeira River basins, and another high risk area to the east, on the Roosevelt reserve. Conclusion By means of kernel mapping, it was shown that malaria risk varies widely between Indian reserves and environmental zones defined on the basis of predominant ecologic characteristics and land use patterns observed in the southwestern Brazilian Amazon. The geographical approach in this paper helped to determine where the greatest needs lie for more intensively focused malaria control activities in Indian reserves in the region. It also provided a reference to assess the effectiveness of control measures that have been put in place by Brazilian public health authorities.

  11. Santarém, entre la Amazonia de los ríos y la Amazonia de las carreteras Santarém, entre l’Amazonie des fleuves et l’Amazonie des routes

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    Ruben Valbuena

    2008-04-01

    égional, jusque là dominé par la maille fluviale et un faible réseau de lieux peuplés, formé par les noyaux de population apparus au bord des voies navigables. Santarém, une ville historique à la localisation stratégique entre les deux plus grands centres urbains amazoniens, a été le théâtre de transformations énormes depuis la construction des routes, parce que sa liaison, via la route Cuibá-Santarém, au Centre Ouest du Brésil et via la Transamazonienn au Nord-est brésilien et  à l'Amazonie Occidentale a commencé à jouer un rôle important comme articulateur de la région Nord. En même temps, elle est devenue comme le principal foyer de peuplement de cette vaste région centrale, en organisant un processus émergent de construction régionale.The great northern area of Brazil, Amazonia, which during several centuries represented only an enormous vacuum and a source of potential richness, has been during the last half-century the object of an accelerated process of occupation and of intensive exploitation. A strong dynamics of appropriation facilitated the incursion of new human and financial resources into the Amazonian hinterland, especially during three last decades, when the realization of a ground network articulated the right bank of the big river.This network restructured the regional space, until then dominated by the rivers and a weak network of populated places, formed by small settlements at the edge of the inland waterways. Santarém, a historical city with a strategic localization between the two greater Amazonian urban centres, has been the theatre of enormous transformations since the construction of the road. The connection, via the Cuibá-Santarém road, with the Center-West region of Brazil and, via Transamazonian road, with the Brazilian North-East and Western Amazonia, started to play a significant role as articulator of the Northern area. At the same time, it became the principal focus of settlement of this vast central area, by

  12. Distance decay of tree species similarity in protected areas on terra firme forests in Colombian Amazonia

    NARCIS (Netherlands)

    Duque, Á.; Phillips, J.F.; von Hildebrand, P.; Posada, C.A.; Prieto, A.; Rudas, A.; Suescún, M.; Stevenson, P.

    2009-01-01

    In this study, we investigated the pattern of floristic similarity as a function of geographical distances and environmental variability in well-drained uplands (terra firme) in Colombian Amazonia. The study site comprised three National Natural Parks, Tinigua, Chiribiquete, and Amacayacu, located

  13. Estimates of the height of the boundary layer using SODAR and rawinsoundings in Amazonia

    Energy Technology Data Exchange (ETDEWEB)

    Fisch, G [Instituto de Aeronautica e Espaco (IAE/CTA), Sao Jose dos Campos, 12228-904 (Brazil); Santos, L A R dos [Instituto Nacional de Meteorologia (INMET), BrasIlia, 70680-900 (Brazil)], E-mail: gfisch@iae.cta.br, E-mail: landre@inmet.gov.br

    2008-05-01

    During the LBA campaign in Amazonia 2002, simultaneous measurements were made of the boundary layer using different instruments (rawinsoundings and SODAR). The profiles of potential temperature and humidity were used to estimates the height of the boundary layer using 3 different techniques. The SODAR's measurements did not capture the shallow morning boundary layer observed at the profiles.

  14. The Amazonian Craton and its influence on past fluvial systems (Mesozoic-Cenozoic, Amazonia)

    NARCIS (Netherlands)

    Hoorn, C.; Roddaz, M.; Dino, R.; Soares, E.; Uba, C.; Ochoa-Lozano, D.; Mapes, R.; Hoorn, C.; Wesselingh, F.P.

    2010-01-01

    The Amazonian Craton is an old geological feature of Archaean/Proterozoic age that has determined the character of fluvial systems in Amazonia throughout most of its past. This situation radically changed during the Cenozoic, when uplift of the Andes reshaped the relief and drainage patterns of

  15. Amazon forest dynamics under changing abiotic conditions in the early Miocene (Colombian Amazonia)

    NARCIS (Netherlands)

    Salamanca Villegas, S.; van Soelen, E.; Teunissen van Manen, M.L.; Flantua, S.G.A.; Santos, R.V.; Roddaz, M.; Dantas, E.L.; van Loon, E.; Sinninghe Damsté, J.S.; Kim, J.-H.; Hoorn, C.

    2016-01-01

    Aim We analysed in detail a past marine incursion event in north-westernAmazonia and measured its effect on the forest composition. We also deter-mined the sediment provenance in the ?uvio-estuarine system and recon-structed the overall ?oral composition of the Amazon lowland forest duringthe

  16. Species richness and distribution of understorey bryophytes in different forest types in Colombian Amazonia

    NARCIS (Netherlands)

    Benavides, J.C.; Duque, A.J.; Duivenvoorden, J.F.; Cleef, A.M.

    2006-01-01

    The first bryophyte survey results from Colombian Amazonia are presented. Bryophyte species, differentiated into mosses and liverworts, and further into four life-form classes, were sampled in 0.1-ha plots. These plots were distributed over four landscape units in the middle Caquetá area:

  17. Amazon forest dynamics under changing abiotic conditions in the early Miocene (Colombian Amazonia)

    NARCIS (Netherlands)

    Salamanca, S.; van Soelen, E.E.; Teunissen van Manen, Milan L.; Flantua, Suzette G.A.; Ventura Santos, Roberto; Roddaz, M.; Dantas, Elton Luiz; van Loon, Emiel; Sinninghe Damsté, J.S.; Kim, J.H.; Hoorn, Carina

    2016-01-01

    Aim We analysed in detail a past marine incursion event in north-western Amazonia and measured its effect on the forest composition. We also determined the sediment provenance in the fluvio-estuarine system and reconstructed the overall floral composition of the Amazon lowland forest during the

  18. Modeling fire-driven deforestation potential in Amazonia under current and projected climate conditions

    NARCIS (Netherlands)

    Le Page, Y.; van der Werf, G.R.; Morton, D.C.; Pereira, J.M.C.

    2010-01-01

    Fire is a widely used tool to prepare deforested areas for agricultural use in Amazonia. Deforestation is currently concentrated in seasonal forest types along the arc of deforestation, where dry-season conditions facilitate burning of clear-felled vegetation. Interior Amazon forests, however, are

  19. Carbon replacement and stability changes in short-term silvo-pastoralo experiments in Colombian Amazonia

    NARCIS (Netherlands)

    Mosquera Vidal, O.; Buurman, P.; Ramirez, B.L.; Amezquita, M.C.

    2012-01-01

    There is little information on the effects of land use change on soil Carbon stocks in Colombian Amazonia. Such information would be needed to assess the impact of this area on the global C cycle and the sustainability of agricultural systems that are replacing native forest. The aim of this study

  20. Qualidade de sementes de soja BRS Tracajá, colhidas em Roraima em função do tamanho no armazenamento

    Directory of Open Access Journals (Sweden)

    Cylles Zara dos Reis Barbosa

    Full Text Available Resumo O objetivo deste trabalho foi avaliar a qualidade física e fisiológica de sementes de soja, cv BRS Tracajá, colhidas em área de cerrado de Roraima em função do tamanho e armazenamento. As sementes foram limpas e classificadas por tamanho, utilizando-se três peneiras de crivos redondos de dimensões 5,5; 6,0 e 6,5 mm, em seguida, acondicionadas em sacos de papel multifoliado e armazenadas durante 6 meses, com temperatura de 23 ºC e umidade relativa do ar de 60%, no laboratório de analise de sementes da Embrapa Roraima. A qualidade das sementes foi avaliada, no início do armazenamento e após 2; 4 e 6 meses, quanto ao peso de mil sementes, germinação, primeira contagem de germinação, condutividade elétrica, emergência de plântula em campo, velocidade de emergência de plântula em campo, peso seco das plântulas e peso seco por plântula. Os resultados mostram que o tamanho das sementes influencia na qualidade física e fisiológica das sementes da cultivar BRS Tracajá durante o armazenamento. As sementes de maiores tamanhos, da cultivar BRS Tracajá (6,5 mm, apresentam maior peso de mil sementes. As maiores porcentagens de germinação e vigor pelo teste de condutividade elétrica das sementes de soja da cultivar BRS Tracajá, durante o armazenamento, foram obtidas nas sementes de maiores tamanhos (6,0 e 6,5 mm. As sementes de maiores tamanhos (6,0 e 6,5 mm da cultivar BRS Tracajá apresentam, durante o armazenamento, a maior porcentagem de emergência de plântula em campo, e as sementes de menores tamanhos (5,5 mm, os menores índices de velocidade de emergência de plântula em campo.

  1. Hornborg, A. & Hill, J. D. (eds. 2011. Ethnicity in Ancient Amazonia: Reconstructing Past Identities from Archaeology, Linguistics and Ethnohistory

    Directory of Open Access Journals (Sweden)

    Phil Riris

    2013-02-01

    Full Text Available Book review: Hornborg, A. & Hill, J. D. (eds. 2011. 'Ethnicity in Ancient Amazonia:' 'Reconstructing Past Identities from Archaeology, Linguistics and Ethnohistory.' Boulder: University Press of Colorado, £60

  2. LBA-ECO LC-04 Satellite/Census-Based 5-Minute Land Use Data, Amazonia: 1980 and 1995

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains 5-minute land use maps for agricultural activity in Amazonia. The data set was produced by the statistical fusion of agricultural census data...

  3. Ocorrência de Passalora bougainvilleae (Muntañola Castañeda & Braun associado à Bougainvillea spectabilis Willd. em Boa Vista, Roraima Repot of Passalora bougainvilleae (Muntañola Castañeda & Braun associated with Bougainvillea spectablis Willd. in Boa Vista, Roraima

    Directory of Open Access Journals (Sweden)

    Kátia de Lima Nechet

    2008-01-01

    Full Text Available O fungo Passalora bougainvilleae é relatado, pela primeira vez, na região de Boa Vista, Roraima, associado a manchas foliares na planta ornamental Bougainvillea spectabilis. As características do fungo são conidióforos agregados em fascículos, emergindo de um estroma subcuticular na face abaxial de lesões velhas. Os conidióforos são lisos, retos, de coloração marrom, não ramificados, maioria asseptados, medindo de 26-57µm x 4µm. Células conidiogênicas terminais de proliferação simpodial com cicatrizes escuras e pouco espessas. Os conídios são solitários, marrom claro, obclavados, retos a ligeiramente curvos, medindo de 32-70 µm x 4-5 µm, maioria com 3 septos, apresentando um hilo truncado e ápice obtuso.The fungi Passalora bougainvilleae is reported, for the first time, Boa Vista, Roraima state, causing leaf spots on ornamental specie Bougainvillea spectabilis. The fungi characteristics are conidiophores hypophyllous in fascicles arising from the upper cells of a stroma subcuticular at old spots. The conidiphores are smooth, straight, pale brown, non-branched, mostly aseptate, 26-57µm x 4µm. Conidiogenous cells terminal, sympodial with black and thin scars. Conidia solitary, pale brown, obclavate, straight to slightly flexuous, 32-70 µm x 4-5 µm, 3 septate, rounded at apex, truncate at base, with a conspicuous hilum.

  4. Impact of Biomass Burning Aerosols on the Biosphere over Amazonia

    Science.gov (United States)

    Malavelle, F.; Haywood, J.; Mercado, L.; Folberth, G.; Bellouin, N.

    2014-12-01

    Biomass burning (BB) smoke from deforestation and the burning of agricultural waste emit a complex cocktail of aerosol particles and gases. BB emissions show a regional hotspot over South America on the edges of Amazonia. These major perturbations and impacts on surface temperature, surface fluxes, chemistry, radiation, rainfall, may have significant consequent impacts on the Amazon rainforest, the largest and most productive carbon store on the planet. There is therefore potential for very significant interaction and interplay between aerosols, clouds, radiation and the biosphere in the region. Terrestrial carbon production (i.e. photosynthesis) is intimately tied to the supply of photosynthetically active radiation (PAR - i.e. wavelengths between 300-690 nm). PAR in sufficient intensity and duration is critical for plant growth. However, if a decrease in total radiation is accompanied by an increase in the component of diffuse radiation, plant productivity may increase due to higher light use efficiency per unit of PAR and less photosynthetic saturation. This effect, sometimes referred as diffuse light fertilization effect, could have increased the global land carbon sink by approximately one quarter during the global dimming period and is expected to be a least as important locally. By directly interacting with radiation, BB aerosols significantly reduce the total amount of PAR available to plant canopies. In addition, BB aerosols also play a centre role in cloud formation because they provide the necessary cloud condensation nuclei, hence indirectly altering the water cycle and the components and quantity of PAR. In this presentation, we use the recent observations from the South American Biomass Burning Analysis (SAMBBA) to explore the impact of radiation changes on the carbon cycle in the Amazon region caused by BB emissions. A parameterisation of the impact of diffuse and direct radiation upon photosynthesis rates and net primary productivity in the

  5. Continuous soil carbon storage of old permanent pastures in Amazonia.

    Science.gov (United States)

    Stahl, Clément; Fontaine, Sébastien; Klumpp, Katja; Picon-Cochard, Catherine; Grise, Marcia Mascarenhas; Dezécache, Camille; Ponchant, Lise; Freycon, Vincent; Blanc, Lilian; Bonal, Damien; Burban, Benoit; Soussana, Jean-François; Blanfort, Vincent

    2017-08-01

    Amazonian forests continuously accumulate carbon (C) in biomass and in soil, representing a carbon sink of 0.42-0.65 GtC yr -1 . In recent decades, more than 15% of Amazonian forests have been converted into pastures, resulting in net C emissions (~200 tC ha -1 ) due to biomass burning and litter mineralization in the first years after deforestation. However, little is known about the capacity of tropical pastures to restore a C sink. Our study shows in French Amazonia that the C storage observed in native forest can be partly restored in old (≥24 year) tropical pastures managed with a low stocking rate (±1 LSU ha -1 ) and without the use of fire since their establishment. A unique combination of a large chronosequence study and eddy covariance measurements showed that pastures stored between -1.27 ± 0.37 and -5.31 ± 2.08 tC ha -1  yr -1 while the nearby native forest stored -3.31 ± 0.44 tC ha -1  yr -1 . This carbon is mainly sequestered in the humus of deep soil layers (20-100 cm), whereas no C storage was observed in the 0- to 20-cm layer. C storage in C4 tropical pasture is associated with the installation and development of C3 species, which increase either the input of N to the ecosystem or the C:N ratio of soil organic matter. Efforts to curb deforestation remain an obvious priority to preserve forest C stocks and biodiversity. However, our results show that if sustainable management is applied in tropical pastures coming from deforestation (avoiding fires and overgrazing, using a grazing rotation plan and a mixture of C3 and C4 species), they can ensure a continuous C storage, thereby adding to the current C sink of Amazonian forests. © 2016 John Wiley & Sons Ltd.

  6. First report of Lecanodiaspis dendrobii Douglas, 1892 (Hemiptera: Lecanodiaspididae and the associated parasitoid Cephaleta sp. (Hymenoptera: Pteromalidae in Brazil

    Directory of Open Access Journals (Sweden)

    A. L. Marsaro Júnior

    Full Text Available Abstract Lecanodiaspis dendrobii Douglas, 1892 (Hemiptera: Coccoidea: Lecanodiaspididae and the associated parasitoid Cephaleta sp. (Hymenoptera: Pteromalidae are reported for the first time in Brazil. Specimens of this scale insect were collected on branches and stems of Acacia mangium Willd., Leucaena leucocephala (Lam. de Wit (Fabaceae, Morus nigra L. (Moraceae, Citrus reticulata Blanco (Rutaceae, Tectona grandis L. f. (Verbenaceae, Anacardium occidentale (Anacardiaceae, Annona squamosa L. and Xylopia aromatica (Lam. Mart. (Annonaceae, in three municipalities of the Roraima state. All plants here mentioned are recorded for the first time as a host for L. dendrobii. Morphological characters of L. dendrobii and symptoms presented by the host plants infested by this pest are included in this work.

  7. Plantation forestry in Brazil: the potential impacts of climatic change

    International Nuclear Information System (INIS)

    Fearnside, P.M.

    1999-01-01

    Most climatic changes predicted to occur in Brazil would replace yields of silvicultural plantations, mainly through increased frequency and severity of droughts brought on by global warming and by reduction of water vapor sources in Amazonia caused by deforestation. Some additional negative effects could result from changes in temperature, and positive effects could result from CO 2 enrichment. The net effects would be negative, forcing the country to expand plantations onto less-productive land, requiring increased plantation area (and consequent economic losses) out of proportion to the climatic change itself. These impacts would affect carbon sequestration and storage consequences of any plans for subsidizing silviculture as a global warming mitigation option. Climate change can be expected to increase the area of plantations needed to supply projected internal demand for and exports of end products from Brazil. June-July-August (dry season) precipitation reductions indicated by simulations reported by the Intergovernmental Panel on Climate Change (IPCC) correspond to rainfall declines in this critical season of approximately 34% in Amazonia, 39% in Southern Brazil and 61% in the Northeast. As an example, if rainfall in Brazilian plantation areas (most of which are now in Southern Brazil) were to decline by 50%, the area needed in 2050 would expand by an estimated 38% over the constant climate case, bringing the total area to 4.5 times the 1991 area. These large areas of additional plantations imply substantial social and environmental impacts. Further addition of plantation area as a global warming response option would augment these impacts, indicating the need for caution in evaluating carbon sequestration proposals. (author)

  8. Downgrading, downsizing, degazettement, and reclassification of protected areas in Brazil.

    Science.gov (United States)

    Bernard, E; Penna, L A O; Araújo, E

    2014-08-01

    Protected areas (PAs) are key elements for biodiversity conservation and ecosystem services. Brazil has the largest PA system in the world, covering approximately 220 million ha. This system expanded rapidly in the mid-1990s to the mid-2000s. Recent events in Brazil, however, have led to an increase in PA downgrading, downsizing, and degazettement (PADDD). Does this reflect a shift in the country's PA policy? We analyzed the occurrence, frequency, magnitude, type, spatial distribution, and causes of changes in PA boundaries and categories in Brazil. We identified 93 PADDD events from 1981 to 2012. Such events increased in frequency since 2008 and were ascribed primarily to generation and transmission of electricity in Amazonia. In Brazilian parks and reserves, 7.3 million ha were affected by PADDD events, and of these, 5.2 million ha were affected by downsizing or degazetting. Moreover, projects being considered by the Federal Congress may degazette 2.1 million ha of PA in Amazonia alone. Relaxing the protection status of existing PAs is proving to be politically easy in Brazil, and the recent increase in frequency and extension of PADDD reflects a change in governmental policy. By taking advantage of chronic deficiencies in financial and personnel resources and surveillance, disputes over land tenure, and the slowness of the Brazilian justice, government agencies have been implementing PADDD without consultation of civil society. If parks and reserves are to maintain their integrity, there will need to be investments in Brazilian PAs and a better understanding of the benefits PAs provide. © 2014 Society for Conservation Biology.

  9. ESTRUTURA, DISTRIBUIÇÃO ESPACIAL E PRODUÇÃO DE SEMENTES DE ANDIROBA (Carapa guianensis Aubl. NO SUL DO ESTADO DE RORAIMA

    Directory of Open Access Journals (Sweden)

    Helio Tonini

    2009-01-01

    Full Text Available Andiroba is one of the Amazon species with great potential of exploration for timber and non-timber forest products (NFTPs. This work was carried out with the objective of studying the population structure, spatial distribution and seed yield in a native forest of andiroba in the south of Roraima state. A permanent sample plot of 300 x 300 m (9 ha was installed and all the trees with DBH equal or superior to 10 cm were identified, mapped and measured. In each tree, the light climate, crown form and lianas load were appraised. To identify the spatial distribution, the medium variance/average rate and the Morisita¿s Index were used. The seed yield data were obtained by the seed weighing, being 145 trees monitored during 2006. The population presented a diametric distribution of the j inverted type, and a seed yield of 65,4 kg.ha-1 with average of 8,3 kg.tree-1 was observed. DBH > 30 cm was considered as borderline for commercial seed yield, allowing stratifying the population in juveniles (DBH > 30 cm and adults (DBH > 30 cm. The spatial distribution analysis showed that adult individuals presented random distribution and the juveniles tendency of grouping.

  10. Intraspecific variability of camu-camu fruit in native populations of northern Amazonia

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    Edvan Alves Chagas

    2015-12-01

    Full Text Available Similarly to most breeding programs of native species, camu-camu (Myrciaria dubia (Kunt McVaugh improvement is also restricted, due to the scarcity of research results. In this situation, the prospection, collection and conservation of germplasm in genebanks ensure successful selection and breeding studies of the species. In this sense, the purpose of this study was the intraspecific characterization of the biometric variability in fruits of native camu-camu populations of the State of Roraima, in the northern Amazon region. Of 16 populations, 247 sub-samples were evaluated. Analyses were performed with the multivariate technique of principal components and hierarchical clustering, to determine the variables with highest intraspecific variability for the studied traits. The populations found in the lower Rio Branco region performed best for the studied traits, indicating the great potential of the region as a reservoir of promising subsamples for future breeding programs of the species in the northern Amazon.

  11. Soil texture derived from topography in North-eastern Amazonia

    OpenAIRE

    Laurent, François; Poccard-Chapuis, René; Plassin, Sophie; Pimentel Martinez, Gustavo

    2017-01-01

    We present a 1:100,000 scale soil texture map of Paragominas county (Pará, Brazil), covering 19,330 km2. The method allows rapid production of a soil texture map of a large area where the strength of a duricrust controls the relief. It is based on an easily accessible explanatory variable, topography, which is represented using a Digital Elevation Model. The method makes it possible to map the spatial distribution of the texture of the topsoil layer. Modelling was complemented by field observ...

  12. Edaphic and light conditions of sympatric plant morphotypes in western Amazonia

    Directory of Open Access Journals (Sweden)

    Julissa Roncal

    2014-05-01

    Full Text Available Here I present a dataset of edaphic and light conditions associated with the occurrence of sympatric morphotypes of Geonoma macrostachys (Arecaceae/Palmae, a candidate case study from Amazonia hypothesized to have evolved under ecological speciation. Transects were established in three lowland rainforests in Peru, and the abundance of each local morphotype of this species was recorded in a total area of 4.95 hectares. Composite soil samples and hemispherical photographs were taken along the transects were the species occurred to obtain information on soil nutrients, soil texture, and indirect measurements of light availability. The raw and summary tables disclose the characteristics of each study site and habitats within them, which could be useful to soil scientists, ecologists, and conservationists engaged in similar research activities or meta-analyses in Amazonia.

  13. The Roles and Movements of Actors in the Deforestation of Brazilian Amazonia

    OpenAIRE

    Philip M. Fearnside

    2008-01-01

    Containing the advance of deforestation in Brazilian Amazonia requires understanding the roles and movements of the actors involved. The importance of different actors varies widely among locations within the region, and also evolves at any particular site over the course of frontier establishment and consolidation. Landless migrants have significant roles in clearing the land they occupy and in motivating landholders to clear as a defense against invasion or expropriation. Colonists in offic...

  14. IKONOS imagery for the Large Scale Biosphere–Atmosphere Experiment in Amazonia (LBA).

    Science.gov (United States)

    George Hurtt; Xiangming Xiao; Michael Keller; Michael Palace; Gregory P. Asner; Rob Braswell; Brond& #305; Eduardo S. zio; Manoel Cardoso; Claudio J.R. Carvalho; Matthew G. Fearon; Liane Guild; Steve Hagen; Scott Hetrick; Berrien Moore III; Carlos Nobre; Jane M. Read; S& aacute; Tatiana NO-VALUE; Annette Schloss; George Vourlitis; Albertus J. Wickel

    2003-01-01

    The LBA-ECO program is one of several international research components under the Brazilian-led Large Scale Biosphere–Atmosphere Experiment in Amazonia (LBA). The field-oriented research activities of this study are organized along transects and include a set of primary field sites, where the major objective is to study land-use change and ecosystem dynamics, and a...

  15. Molecular composition of organic aerosols in central Amazonia: an ultra-high-resolution mass spectrometry study

    OpenAIRE

    Kourtchev, I; Godoi, RHM; Connors, S; Levine, JG; Archibald, AT; Godoi, AFL; Paralovo, SL; Barbosa, CGG; Souza, RAF; Manzi, AO; Seco, R; Sjostedt, S; Park, J-H; Guenther, A; Kim, S

    2016-01-01

    The Amazon Basin plays key role in atmospheric chemistry, biodiversity and climate change. In this study we applied nanoelectrospray (nanoESI) ultra-high-resolution mass spectrometry (UHRMS) for the analysis of the organic fraction of PM$_{2.5}$ aerosol samples collected during dry and wet seasons at a site in central Amazonia receiving background air masses, biomass burning and urban pollution. Comprehensive mass spectral data evaluation methods (e.g. Kendrick mass defect, Van Krevelen diagr...

  16. Bryophyte diversity patterns in flooded and tierra firme forests in the Araracuara Region, Colombian Amazonia

    OpenAIRE

    Benavides, Juan C.; Idarraga, Alvaro; Alvarez, Esteban

    2004-01-01

    We investigated patterns of bryophyte species richness and composition in two forest types of Colombian Amazonia, non-flooded tierra firme forest and floodplain forest of the Caquetá River. A total of 109 bryophyte species were recorded from 14 0.2 ha plots. Bryophyte life forms and habitats were analyzed, including the canopy and epiphylls. Bryophyte species did not show significant differences between landscapes but mosses and liverworts were different and with opposite responses balancing ...

  17. Conversion of land use and cover in northwest Amazon (Brazil

    Directory of Open Access Journals (Sweden)

    Carlos Antonio da Silva Junior

    2014-09-01

    Full Text Available The increasing use of natural resources in a disorderly way has been demanding constant monitoring and ecological-economic zoning. The knowledge on land use and cover allows that measures that guarantee the preservation, maintenance of the environment and space management be appropriate to the reality, since through these factors it is possible to follow the probable environmental impacts and the socioeconomic development of a place in several contexts. The Geographical Information System (GIS and remote sensing techniques have been applied to land use and land cover mapping. This study aimed to analyze the conversion of land use from different perspectives, concerning geoprocessing techniques, in the southeastern of Roraima State, Brazil, in two distinct periods. In order to verify the land use and cover, two analyses were conducted, using the Spring and TerraView softwares. Great part of the cultivated areas was converted into capoeira, what probably denotes an ending of profitable agriculture, as well as its abandonment caused by the nutritional deficiency of the soil, that became inappropriate for cultivation in the subsequent years. A fuzzy logic would possibly fit well to the types of data analyzed, because the attribute query is overly complex.

  18. Radiochronological age and correlation of proterozoic sediments in Brazil

    International Nuclear Information System (INIS)

    Bonhomme, M.G.; Macedo, M.-H.F.; Filho, A.T.

    1982-01-01

    A review of available Rb-Sr and K-Ar datings obtained on sedimentary sequences, metamorphosed or not, interbedded volcanics and cross-cutting intrusives of the Precambrian of Brazil yields the following conclusions: (1) The Roraima and Rio Fresco Formations, resting upon the Amazonian craton, have been affected by the Trans-Amazonian orogeny and are of Lower Proterozoic age. (2) The Beneficiente Group, in the same region, seems to be of Middle Proterozoic, Lower Riphean age. (3) Upon the Sao Francisco craton, and upon the Lower Proterozoic Rio dos Remedios complex, the Paraguacu Group might be of middle Riphean age and the glacial sequences, Macaubas Group and Bebedouro Formation, date back to between 950 and 1000 Ma. (4) The age of the Bambui and Una Groups, in the same region, remains undetermined. It might be either Upper Riphean, or Upper Riphean and Vendian. (5) The molassic series associated with the Brazilian orogeny are dated back to between the Proterozoic-Phanerozoic boundary and the Ordovician. (Auth.)

  19. Biomass power production in Amazonia: Environmentally sound, economically productive

    Energy Technology Data Exchange (ETDEWEB)

    Waddle, D.B. [National Rural Electric Cooperative Association, Washington, DC (United States); Hollomon, J.B. [Winrock International Institute for Agricultural Development, Arlington, VA (United States)

    1993-12-31

    With the support of the US Agency for International Development, the National Rural Electric Cooperative Association (NRECA) is assisting their utility counterparts in Bolivia to improve electric service in the country`s rural population. In remote areas, the cost of extending transmission lines to small communities is prohibitive, and diesel generators represent an expensive alternative, especially for baseload power. This has led to serious consideration of electric generating systems using locally available renewable resources, including biomass, hydro, wind, and solar energy. A project has recently been initiated in Riberalta, in the Amazonian region of Bolivia, to convert waste Brazil nut shells and sawmill residues to electricity. Working in tandem with diesel generators, the biomass-fired plant will produce base-load power in an integrated system that will be able to provide reliable and affordable electricity to the city. The project will allow the local rural electric cooperative to lower the price of electricity by nearly forty percent, enable the local Brazil nut industry to increase its level of mechanization, and reduce the environmental impacts of dumping waste shells around the city and in an adjacent river. The project is representative of others that will be funded in the future by NRECA/AID.

  20. Hydro-climate and ecological behaviour of the drought of Amazonia in 2005.

    Science.gov (United States)

    Marengo, J A; Nobre, C A; Tomasella, J; Cardoso, M F; Oyama, M D

    2008-05-27

    In 2005, southwestern Amazonia experienced the effects of an intense drought that affected life and biodiversity. Several major tributaries as well as parts of the main river itself contained only a fraction of their normal volumes of water, and lakes were drying up. The consequences for local people, animals and the forest itself are impossible to estimate now, but they are likely to be serious. The analyses indicate that the drought was manifested as weak peak river season during autumn to winter as a consequence of a weak summertime season in southwestern Amazonia; the winter season was also accompanied by rainfall that sometimes reached 25% of the climatic value, being anomalously warm and dry and helping in the propagation of fires. Analyses of climatic and hydrological records in Amazonia suggest a broad consensus that the 2005 drought was linked not to El Niño as with most previous droughts in the Amazon, but to warming sea surface temperatures in the tropical North Atlantic Ocean.

  1. Forest productivity and water stress in Amazonia: observations from GOSAT chlorophyll fluorescence.

    Science.gov (United States)

    Lee, Jung-Eun; Frankenberg, Christian; van der Tol, Christiaan; Berry, Joseph A; Guanter, Luis; Boyce, C Kevin; Fisher, Joshua B; Morrow, Eric; Worden, John R; Asefi, Salvi; Badgley, Grayson; Saatchi, Sassan

    2013-06-22

    It is unclear to what extent seasonal water stress impacts on plant productivity over Amazonia. Using new Greenhouse gases Observing SATellite (GOSAT) satellite measurements of sun-induced chlorophyll fluorescence, we show that midday fluorescence varies with water availability, both of which decrease in the dry season over Amazonian regions with substantial dry season length, suggesting a parallel decrease in gross primary production (GPP). Using additional SeaWinds Scatterometer onboard QuikSCAT satellite measurements of canopy water content, we found a concomitant decrease in daily storage of canopy water content within branches and leaves during the dry season, supporting our conclusion. A large part (r(2) = 0.75) of the variance in observed monthly midday fluorescence from GOSAT is explained by water stress over moderately stressed evergreen forests over Amazonia, which is reproduced by model simulations that include a full physiological representation of photosynthesis and fluorescence. The strong relationship between GOSAT and model fluorescence (r(2) = 0.79) was obtained using a fixed leaf area index, indicating that GPP changes are more related to environmental conditions than chlorophyll contents. When the dry season extended to drought in 2010 over Amazonia, midday basin-wide GPP was reduced by 15 per cent compared with 2009.

  2. Misiones religiosas y políticas identitarias: Las misiones de los consolatinos en Kenia y Roraima Religious missons and identity policies: The consolatinos' missons in Kenia and Roraima

    Directory of Open Access Journals (Sweden)

    Melvina Araújo

    2008-06-01

    Full Text Available La intención de este artículo es discutir la elaboración de nuevas formas de alteridad a partir de la interconexión entre la organización de grupos que se representan y/o son representados como étnicos, la formulación de conceptos de etnia y las políticas públicas instituidas por presiones de movimientos sociales y/o internacionales. Esto se hará teniendo como base una parte de la bibliografía producida sobre el tema, considerándose también los datos empíricos surgidos de la investigación realizada sobre las relaciones entre una congregación misionera católica y los indios macuxi, en Brasil, y entre esta misma congregación y los kikuyu, en Kenia.This article aims to discuss the development of new forms of alterity from the interconnection between the organization of groups which represent and / or are represented as ethnic, the formulation of the concepts of ethnicity and public policies imposed by pressures from social movements and/or international. This will be done on the basis of the literature produced on the subject, as well as empirical data arising from research on the relations between a catholic missionary congregation and the macuxi Indians in Brazil , and from the same congregation and the kikuyu in Kenya.

  3. First report of Maconellicoccus hirsutus (Green, 1908) (Hemiptera: Coccoidea: Pseudococcidae) and the associated parasitoid Anagyrus kamali Moursi, 1948 (Hymenoptera: Encyrtidae), in Brazil.

    Science.gov (United States)

    Marsaro Júnior, A L; Peronti, A L B G; Penteado-Dias, A M; Morais, E G F; Pereira, P R V S

    2013-05-01

    The pink hibiscus mealybug (PHM), Maconellicoccus hirsutus (Green) (Hemiptera: Pseudococcidae) and the associated hymenopterous parasitoid, Anagyrus kamali Moursi, 1948 (Hymenoptera: Encyrtidae), are reported for the first time in Brazil. Specimens of the PHM were collected on nine hosts plants, Annona muricata L. (Anonnaceae), Glycine max (L.) Merr. (Fabaceae), Centrolobium paraensis Tul. (Fabaceae), Inga edulis Mart. (Fabaceae), Hibiscus rosa-sinensis L. (Malvaceae), Psidium guajava L. (Myrtaceae), Averrhoa carambola L. (Oxalidaceae), Citrus sinensis (L.) Osbeck (Rutaceae) and Solanum lycopersicum L. (Solanaceae), in four municipalities in the north-northeast of the state of Roraima. The plants C. paraensis, I. edulis and C. sinensis are recorded for the first time as a hosts for PHM. Characteristic injuries observed on the host plants infested by PHM and suggestions for its management are presented.

  4. Crescimento de espécies nativas da Amazônia submetidas ao plantio no estado de Roraima

    Directory of Open Access Journals (Sweden)

    Helio Tonini

    2008-01-01

    Full Text Available An important forest research challenge in the Amazonian is finding forms of reforesting degraded areas with the use of a larger number of native species and identify tropical species commercially attractive adapted to clear-cut areas. This work had as objectives to evaluate the initial growth in diameter and height of six native Amazonian species in a preliminary species trial. The data were obtained from measures of 72 trees 9 years after planting. The selected species for this study were cupiúba (Goupia glabra, cumaru (Dipterix odorata, andiroba (Carapa guianensis, brazil nut (Bertholletia excelsa, pará-pará (Jacaranda copaia and tatajuba (Bagassa guianensis. The cumulative growth curves for diameter and height was obtained by the Chapman – Richards function. In spite of the low age of the stands, it was obtained good fit to the function for the studied species. Pará-pará (Jacaranda copaia, presented best diameter and height growth in all the ages. The diameter mean annual increment analysis showed that, except for the cupiúba (Goupia glabra, can be expected increments larger than 2 cm, by appropiate spacings and thinning.

  5. Remote sensing and conservation of isolated indigenous villages in Amazonia.

    Science.gov (United States)

    Walker, Robert S; Hamilton, Marcus J; Groth, Aaron A

    2014-11-01

    The vast forests on the border between Brazil and Peru harbour a number of indigenous groups that have limited contact with the outside world. Accurate estimates of population sizes and village areas are essential to begin assessing the immediate conservation needs of such isolated groups. In contrast to overflights and encounters on the ground, remote sensing with satellite imagery offers a safe, inexpensive, non-invasive and systematic approach to provide demographic and land-use information for isolated peoples. Satellite imagery can also be used to understand the growth of isolated villages over time. There are five isolated villages in the headwaters of the Envira River confirmed by overflights that are visible with recent satellite imagery further confirming their locations and allowing measurement of their cleared gardens, village areas and thatch roofed houses. These isolated villages appear to have population densities that are an order of magnitude higher than averages for other Brazilian indigenous villages. Here, we report on initial results of a remote surveillance programme designed to monitor movements and assess the demographic health of isolated peoples as a means to better mitigate against external threats to their long-term survival.

  6. Influence of urban pollution on the production of organic particulate matter from isoprene epoxydiols in central Amazonia

    Directory of Open Access Journals (Sweden)

    S. S. de Sá

    2017-06-01

    Full Text Available The atmospheric chemistry of isoprene contributes to the production of a substantial mass fraction of the particulate matter (PM over tropical forests. Isoprene epoxydiols (IEPOX produced in the gas phase by the oxidation of isoprene under HO2-dominant conditions are subsequently taken up by particles, thereby leading to production of secondary organic PM. The present study investigates possible perturbations to this pathway by urban pollution. The measurement site in central Amazonia was located 4 to 6 h downwind of Manaus, Brazil. Measurements took place from February through March 2014 of the wet season, as part of the GoAmazon2014/5 experiment. Mass spectra of organic PM collected with an Aerodyne Aerosol Mass Spectrometer were analyzed by positive-matrix factorization. One resolved statistical factor (IEPOX-SOA factor was associated with PM production by the IEPOX pathway. The IEPOX-SOA factor loadings correlated with independently measured mass concentrations of tracers of IEPOX-derived PM, namely C5-alkene triols and 2-methyltetrols (R = 0. 96 and 0.78, respectively. The factor loading, as well as the ratio f of the loading to organic PM mass concentration, decreased under polluted compared to background conditions. For an increase in NOy concentration from 0.5 to 2 ppb, the factor loading and f decreased by two to three fold. Overall, sulfate concentration explained 37 % of the variability in the factor loading. After segregation of factor loading into subsets based on NOy concentration, the sulfate concentration explained up to 75 % of the variability. Considering both factors, the data sets show that the suppressing effects of increased NO concentrations dominated over the enhancing effects of higher sulfate concentrations. The pollution from Manaus elevated NOy concentrations more significantly than sulfate concentrations relative to background conditions. In this light, increased emissions of nitrogen oxides, as

  7. Pre-Columbian agricultural landscapes, ecosystem engineers, and self-organized patchiness in Amazonia.

    Science.gov (United States)

    McKey, Doyle; Rostain, Stéphen; Iriarte, José; Glaser, Bruno; Birk, Jago Jonathan; Holst, Irene; Renard, Delphine

    2010-04-27

    The scale and nature of pre-Columbian human impacts in Amazonia are currently hotly debated. Whereas pre-Columbian people dramatically changed the distribution and abundance of species and habitats in some parts of Amazonia, their impact in other parts is less clear. Pioneer research asked whether their effects reached even further, changing how ecosystems function, but few in-depth studies have examined mechanisms underpinning the resilience of these modifications. Combining archeology, archeobotany, paleoecology, soil science, ecology, and aerial imagery, we show that pre-Columbian farmers of the Guianas coast constructed large raised-field complexes, growing on them crops including maize, manioc, and squash. Farmers created physical and biogeochemical heterogeneity in flat, marshy environments by constructing raised fields. When these fields were later abandoned, the mosaic of well-drained islands in the flooded matrix set in motion self-organizing processes driven by ecosystem engineers (ants, termites, earthworms, and woody plants) that occur preferentially on abandoned raised fields. Today, feedbacks generated by these ecosystem engineers maintain the human-initiated concentration of resources in these structures. Engineer organisms transport materials to abandoned raised fields and modify the structure and composition of their soils, reducing erodibility. The profound alteration of ecosystem functioning in these landscapes coconstructed by humans and nature has important implications for understanding Amazonian history and biodiversity. Furthermore, these landscapes show how sustainability of food-production systems can be enhanced by engineering into them follows that maintain ecosystem services and biodiversity. Like anthropogenic dark earths in forested Amazonia, these self-organizing ecosystems illustrate the ecological complexity of the legacy of pre-Columbian land use.

  8. Environmental impact of geometric earthwork construction in pre-Columbian Amazonia.

    Science.gov (United States)

    Carson, John Francis; Whitney, Bronwen S; Mayle, Francis E; Iriarte, José; Prümers, Heiko; Soto, J Daniel; Watling, Jennifer

    2014-07-22

    There is considerable controversy over whether pre-Columbian (pre-A.D. 1492) Amazonia was largely "pristine" and sparsely populated by slash-and-burn agriculturists, or instead a densely populated, domesticated landscape, heavily altered by extensive deforestation and anthropogenic burning. The discovery of hundreds of large geometric earthworks beneath intact rainforest across southern Amazonia challenges its status as a pristine landscape, and has been assumed to indicate extensive pre-Columbian deforestation by large populations. We tested these assumptions using coupled local- and regional-scale paleoecological records to reconstruct land use on an earthwork site in northeast Bolivia within the context of regional, climate-driven biome changes. This approach revealed evidence for an alternative scenario of Amazonian land use, which did not necessitate labor-intensive rainforest clearance for earthwork construction. Instead, we show that the inhabitants exploited a naturally open savanna landscape that they maintained around their settlement despite the climatically driven rainforest expansion that began ∼2,000 y ago across the region. Earthwork construction and agriculture on terra firme landscapes currently occupied by the seasonal rainforests of southern Amazonia may therefore not have necessitated large-scale deforestation using stone tools. This finding implies far less labor--and potentially lower population density--than previously supposed. Our findings demonstrate that current debates over the magnitude and nature of pre-Columbian Amazonian land use, and its impact on global biogeochemical cycling, are potentially flawed because they do not consider this land use in the context of climate-driven forest-savanna biome shifts through the mid-to-late Holocene.

  9. Food niche overlap between two sympatric leaf-litter frog species from Central Amazonia

    Directory of Open Access Journals (Sweden)

    Leandro Talione Sabagh

    2012-02-01

    Full Text Available We studied the feeding habits and similarities in the diet of two sympatric and syntopic Amazonian frog species, Anomaloglossus stepheni (Aromobatidae and Leptodactylus andreae (Leptodactylidae in a forested area in Central Amazonia. The breadth of the trophic niche of these species was 5.89 and 3.75, respectively, and approximately 85% of their diets were similar. Ants were main food item in the diets of both frog species. The coexistence between these frog species may be facilitated by the significant differences in the size of their mouths. This difference allows them to consume preys items of different sizes.

  10. 'Formidable contagion': epidemics, work and recruitment in Colonial Amazonia (1660-1750).

    Science.gov (United States)

    Chambouleyron, Rafael; Barbosa, Benedito Costa; Bombardi, Fernanda Aires; Sousa, Claudia Rocha de

    2011-12-01

    The text analyzes the extent to which smallpox and measles epidemics provoked transformations in the ways in which workforces were acquired and used in colonial Amazonia from the mid-seventeenth to mid-eighteenth century, with an increase in slave raids on the indigenous population and the attempt to organize a trade route in African slaves to the region. It also explores how indigenous mortality rates at the end of the seventeenth century led to a concern with the region's defence and prompted the recruitment of soldiers from the Madeira islands.

  11. Producción masiva de Romanomermis iyengari (Nematoda: Mermithidae y su aplicación en criaderos de anofelinos en Boa Vista (Roraima, Brasil

    Directory of Open Access Journals (Sweden)

    Alberto Santamarina Mijares

    2000-03-01

    Full Text Available Para desarrollar la producción masiva del nemátodo Romanomermis iyengari Welch, se llevó a cabo el diseño y montaje de una bioplanta en las instalaciones de la Universidad Federal del Estado de Roraima, Brasil, tras un convenio con la Secretaría de Salud del mencionado estado. El objetivo de este trabajo fue establecer el proceso básico de cría masiva del parásito para su posterior aplicación en criaderos de anofelinos. Se obtuvieron 68 cultivos por cada ciclo de siete días, con un total de 272 cultivos por mes. Antes de los tratamientos de campo se realizaron pruebas de laboratorio en las que se comprobó la gran susceptibilidad de las larvas de anofelinos a la infestación por R. iyengari, con tasas de parasitismo de 71 a 98%. Para evaluar la capacidad parasitaria de R. iyengari en condiciones de campo, se seleccionaron 12 criaderos naturales de anofelinos, con áreas que oscilaron entre 50 y 450 m², en los que se observó la presencia de larvas de mosquitos de las especies Anopheles albitarsis Lynch-Arribálzaga y Anopheles rondoni Neiva-Pinto, con densidades de 34 a 66 larvas/m². Para la dispersión del biolarvicida en los 12 criaderos se utilizó una bomba costal manual de fabricación nacional a una presión de dos atmósferas y se aplicó una dosis de 2 000 preparásitos/m². Siete días después de los tratamientos se observó una marcada reducción (85 a 97% de las poblaciones de anofelinos. Los resultados obtenidos demostraron la posibilidad de utilizar R. iyengari para controlar las poblaciones larvarias de ambas especies de anofelinos.

  12. Producción masiva de Romanomermis iyengari (Nematoda: Mermithidae y su aplicación en criaderos de anofelinos en Boa Vista (Roraima, Brasil

    Directory of Open Access Journals (Sweden)

    Santamarina Mijares Alberto

    2000-01-01

    Full Text Available Para desarrollar la producción masiva del nemátodo Romanomermis iyengari Welch, se llevó a cabo el diseño y montaje de una bioplanta en las instalaciones de la Universidad Federal del Estado de Roraima, Brasil, tras un convenio con la Secretaría de Salud del mencionado estado. El objetivo de este trabajo fue establecer el proceso básico de cría masiva del parásito para su posterior aplicación en criaderos de anofelinos. Se obtuvieron 68 cultivos por cada ciclo de siete días, con un total de 272 cultivos por mes. Antes de los tratamientos de campo se realizaron pruebas de laboratorio en las que se comprobó la gran susceptibilidad de las larvas de anofelinos a la infestación por R. iyengari, con tasas de parasitismo de 71 a 98%. Para evaluar la capacidad parasitaria de R. iyengari en condiciones de campo, se seleccionaron 12 criaderos naturales de anofelinos, con áreas que oscilaron entre 50 y 450 m², en los que se observó la presencia de larvas de mosquitos de las especies Anopheles albitarsis Lynch-Arribálzaga y Anopheles rondoni Neiva-Pinto, con densidades de 34 a 66 larvas/m². Para la dispersión del biolarvicida en los 12 criaderos se utilizó una bomba costal manual de fabricación nacional a una presión de dos atmósferas y se aplicó una dosis de 2 000 preparásitos/m². Siete días después de los tratamientos se observó una marcada reducción (85 a 97% de las poblaciones de anofelinos. Los resultados obtenidos demostraron la posibilidad de utilizar R. iyengari para controlar las poblaciones larvarias de ambas especies de anofelinos.

  13. Solos e geoambientes do Parque Nacional do Viruá e entorno, Roraima: visão integrada da paisagem e serviço ambiental

    Directory of Open Access Journals (Sweden)

    Bruno Araujo Furtado de Mendonça

    2013-01-01

    Full Text Available The Viruá National Park (PARNA Viruá occupies 227.011 ha, in the region of the low ‘Branco’ river, in Roraima state. This area includes an extensive mosaic of complex seasonally flooded forested and nonforested environments. The present work aimed to characterize pedological aspects and identify the geoenvironmental units of the Park and surroundings, in an integrated vision of the landscape and,additionally, estimate the carbon stocks in soils and geo-environments. We described and collected 29 soil profiles according with the main vegetation types of Campinaranas and Forests of PARNA Viruá and surroundings. The main soil classes are: Espodossolo Humilúvico, Neossolo Quartzarênico, Neossolo Flúvico, Neossolo Litólicos, Latossolo Vermelho-Amarelo, Latossolo Vermelho, Cambissolo Háplico, Cambissolo Flúvico, Gleissolo Háplico and Plintossolo Háplico. The soils present an spatial distribution marked by abrupt limits and close association with the vegetation type. We identified three pedo-environments: (1 sandy soils of the Campinaranas; (2 soils associated with the inselbergs and adjacencies; and (3 alluvial soils. We mapped and described 18 geoenvironmental units in PARNA Viruá National Park and surroundings. The main geoenvironments are: i Sandy plains and Paleodunes with grassy and arborous Campinarana on ‘Neossolos Quartzarênicos hidromórficos’ and ‘Espodossolos’; and Floodplains and; ii Terraces with Igapó Forest on sandy hydromorphic soils, occupying 24.6 % and 20.1 % of the studied area, respectively. In terms of total soil carbon stocks, the geo-environments of the sandy complex of Campinaranas and associations stand out, with 9450.9 Gg C. The great extension and representativeness of the sandy areas of Campinaranas characterize PARNA Viruá Park as an important conservation unit for protecting Amazonian sandy soil systems. The areas under the domain of ‘Espodossolos’ possess the largest stocks of organic

  14. Genetic diversity and population structure of the New World screwworm fly from the Amazon region of Brazil.

    Science.gov (United States)

    Mastrangelo, Thiago; Fresia, Pablo; Lyra, Mariana L; Rodrigues, Rosangela A; Azeredo-Espin, Ana Maria L

    2014-10-01

    Cochliomyia hominivorax (Coquerel) is a myiasis fly that causes economic losses to livestock farmers in warmer American regions. Previous studies of this pest had found population structure at north and south of the Amazon Basin, which was considered to be a barrier to dispersal. The present study analyzed three mitochondrial DNA (mtDNA) markers and eight nuclear microsatellite loci to investigate for the first time the genetic diversity and population structure across the Brazilian Amazon region (Amazonia). Both mtDNA and microsatellite data supported the existence of much diversity and significant population structure among nine regional populations of C. hominivorax, which was found to be surprisingly common in Amazonia. Forty-six mtDNA haplotypes were identified, of which 39 were novel and seven had previously been found only at south of Amazonia. Seventy microsatellite alleles were identified by size, moderate to high values of heterozygosity were discovered in all regions, and a Bayesian clustering analysis identified four genetic groups that were not geographically distributed. Reproductive compatibility was also investigated by laboratory crossing, but no evidence of hybrid dysgenesis was found between an Amazonian colony and one each of from Northeast and Southeast Brazil. The results have important implications for area-wide control by the Sterile Insect Technique. Copyright © 2014 International Atomic Energy Agency 2014. Published by Elsevier B.V. All rights reserved.

  15. Geographic distribution of isolated indigenous societies in Amazonia and the efficacy of indigenous territories.

    Science.gov (United States)

    Kesler, Dylan C; Walker, Robert S

    2015-01-01

    The headwaters of the Amazon Basin harbor most of the world's last indigenous peoples who have limited contact with encroaching colonists. Knowledge of the geographic distribution of these isolated groups is essential to assist with the development of immediate protections for vulnerable indigenous settlements. We used remote sensing to document the locations of 28 isolated villages within the four Brazilian states of Acre, Amazonas, Roraima, and Rondônia. The sites were confirmed during previous over-flights and by image evidence of thatched-roof houses; they are estimated to host over 1,700 individuals. Locational data were used to train maximum entropy models that identified landscape and anthropogenic features associated with the occurrence of isolated indigenous villages, including elevation, proximity to streams of five different orders, proximity to roads and settlements, proximity to recent deforestation, and vegetation cover type. Isolated villages were identified at mid elevations, within 20 km of the tops of watersheds and at greater distances from existing roads and trails. We further used model results, combined with boundaries of the existing indigenous territory system that is designed to protect indigenous lands, to assess the efficacy of the existing protected area network for isolated peoples. Results indicate that existing indigenous territories encompass all of the villages we identified, and 50% of the areas with high predicted probabilities of isolated village occurrence. Our results are intended to help inform policies that can mitigate against future external threats to isolated peoples.

  16. Geographic distribution of isolated indigenous societies in Amazonia and the efficacy of indigenous territories.

    Directory of Open Access Journals (Sweden)

    Dylan C Kesler

    Full Text Available The headwaters of the Amazon Basin harbor most of the world's last indigenous peoples who have limited contact with encroaching colonists. Knowledge of the geographic distribution of these isolated groups is essential to assist with the development of immediate protections for vulnerable indigenous settlements. We used remote sensing to document the locations of 28 isolated villages within the four Brazilian states of Acre, Amazonas, Roraima, and Rondônia. The sites were confirmed during previous over-flights and by image evidence of thatched-roof houses; they are estimated to host over 1,700 individuals. Locational data were used to train maximum entropy models that identified landscape and anthropogenic features associated with the occurrence of isolated indigenous villages, including elevation, proximity to streams of five different orders, proximity to roads and settlements, proximity to recent deforestation, and vegetation cover type. Isolated villages were identified at mid elevations, within 20 km of the tops of watersheds and at greater distances from existing roads and trails. We further used model results, combined with boundaries of the existing indigenous territory system that is designed to protect indigenous lands, to assess the efficacy of the existing protected area network for isolated peoples. Results indicate that existing indigenous territories encompass all of the villages we identified, and 50% of the areas with high predicted probabilities of isolated village occurrence. Our results are intended to help inform policies that can mitigate against future external threats to isolated peoples.

  17. Remote sensing of selective logging in Amazonia Assessing limitations based on detailed field observations, Landsat ETM+, and textural analysis.

    Science.gov (United States)

    Gregory P. Asner; Michael Keller; Rodrigo Pereira; Johan C. Zweede

    2002-01-01

    We combined a detailed field study of forest canopy damage with calibrated Landsat 7 Enhanced Thematic Mapper Plus (ETM+) reflectance data and texture analysis to assess the sensitivity of basic broadband optical remote sensing to selective logging in Amazonia. Our field study encompassed measurements of ground damage and canopy gap fractions along a chronosequence of...

  18. Interpreting seasonal changes in the carbon balance of southern Amazonia using measurements of XCO2 and chlorophyll fluorescence from GOSAT

    NARCIS (Netherlands)

    Parazoo, Nicholas C.; Bowman, Kevin; Frankenberg, Christian; Lee, Jung-Eun; Fisher, Joshua B.; Worden, John; Jones, Dylan B. A.; Berry, Joseph; Collatz, G. James; Baker, Ian T.; Jung, Martin; Liu, Junjie; Osterman, Gregory; O'Dell, Chris; Sparks, Athena; Butz, Andre; Guerlet, Sandrine; Yoshida, Yukio; Chen, Huilin; Gerbig, Christoph

    2013-01-01

    Amazon forests exert a major influence on the global carbon cycle, but quantifying the impact is complicated by diverse landscapes and sparse data. Here we examine seasonal carbon balance in southern Amazonia using new measurements of column-averaged dry air mole fraction of CO2 (XCO2) and solar

  19. Accessibility evaluation model to support decision-making in urban investments : the case of Santarém-Brazil

    OpenAIRE

    Ramos, Rui A. R.; Rodrigues, Daniel Souto; Tobias, Maisa

    2011-01-01

    The main goal of the paper is to present an accessibility evaluation model for the urban area of Santarém, in Brazil. Located midway between the larger cities of Belém and Manaus, Santarém plays a crucial role in the region of Lower Amazonia. The paper describes the research instruments, sampling method and data analysis proposed for mapping urban accessibility. Basic activities (education, health, services, leisure and commerce) provided by the city were used to identify the main key-destina...

  20. Evaluating the effect of nutrient redistribution by animals on the phosphorus cycle of lowland Amazonia

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    C. Buendía

    2018-01-01

    Full Text Available Phosphorus (P availability decreases with soil age and potentially limits the productivity of ecosystems growing on old and weathered soils. Despite growing on ancient soils, ecosystems of lowland Amazonia are highly productive and are among the most biodiverse on Earth. P eroded and weathered in the Andes is transported by the rivers and deposited in floodplains of the lowland Amazon basin creating hotspots of P fertility. We hypothesize that animals feeding on vegetation and detritus in these hotspots may redistribute P to P-depleted areas, thus contributing to dissipate the P gradient across the landscape. Using a mathematical model, we show that animal-driven spatial redistribution of P from rivers to land and from seasonally flooded to terra firme (upland ecosystems may sustain the P cycle of Amazonian lowlands. Our results show how P imported to land by terrestrial piscivores in combination with spatial redistribution of herbivores and detritivores can significantly enhance the P content in terra firme ecosystems, thereby highlighting the importance of food webs for the biogeochemical cycling of Amazonia.

  1. Understorey fire frequency and the fate of burned forests in southern Amazonia.

    Science.gov (United States)

    Morton, D C; Le Page, Y; DeFries, R; Collatz, G J; Hurtt, G C

    2013-06-05

    Recent drought events underscore the vulnerability of Amazon forests to understorey fires. The long-term impact of fires on biodiversity and forest carbon stocks depends on the frequency of fire damages and deforestation rates of burned forests. Here, we characterized the spatial and temporal dynamics of understorey fires (1999-2010) and deforestation (2001-2010) in southern Amazonia using new satellite-based estimates of annual fire activity (greater than 50 ha) and deforestation (greater than 10 ha). Understorey forest fires burned more than 85 500 km(2) between 1999 and 2010 (2.8% of all forests). Forests that burned more than once accounted for 16 per cent of all understorey fires. Repeated fire activity was concentrated in Mato Grosso and eastern Pará, whereas single fires were widespread across the arc of deforestation. Routine fire activity in Mato Grosso coincided with annual periods of low night-time relative humidity, suggesting a strong climate control on both single and repeated fires. Understorey fires occurred in regions with active deforestation, yet the interannual variability of fire and deforestation were uncorrelated, and only 2.6 per cent of forests that burned between 1999 and 2008 were deforested for agricultural use by 2010. Evidence from the past decade suggests that future projections of frontier landscapes in Amazonia should separately consider economic drivers to project future deforestation and climate to project fire risk.

  2. Use of MODIS Sensor Images Combined with Reanalysis Products to Retrieve Net Radiation in Amazonia

    Science.gov (United States)

    de Oliveira, Gabriel; Brunsell, Nathaniel A.; Moraes, Elisabete C.; Bertani, Gabriel; dos Santos, Thiago V.; Shimabukuro, Yosio E.; Aragão, Luiz E. O. C.

    2016-01-01

    In the Amazon region, the estimation of radiation fluxes through remote sensing techniques is hindered by the lack of ground measurements required as input in the models, as well as the difficulty to obtain cloud-free images. Here, we assess an approach to estimate net radiation (Rn) and its components under all-sky conditions for the Amazon region through the Surface Energy Balance Algorithm for Land (SEBAL) model utilizing only remote sensing and reanalysis data. The study period comprised six years, between January 2001–December 2006, and images from MODIS sensor aboard the Terra satellite and GLDAS reanalysis products were utilized. The estimates were evaluated with flux tower measurements within the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) project. Comparison between estimates obtained by the proposed method and observations from LBA towers showed errors between 12.5% and 16.4% and 11.3% and 15.9% for instantaneous and daily Rn, respectively. Our approach was adequate to minimize the problem related to strong cloudiness over the region and allowed to map consistently the spatial distribution of net radiation components in Amazonia. We conclude that the integration of reanalysis products and satellite data, eliminating the need for surface measurements as input model, was a useful proposition for the spatialization of the radiation fluxes in the Amazon region, which may serve as input information needed by algorithms that aim to determine evapotranspiration, the most important component of the Amazon hydrological balance. PMID:27347957

  3. Use of MODIS Sensor Images Combined with Reanalysis Products to Retrieve Net Radiation in Amazonia.

    Science.gov (United States)

    de Oliveira, Gabriel; Brunsell, Nathaniel A; Moraes, Elisabete C; Bertani, Gabriel; Dos Santos, Thiago V; Shimabukuro, Yosio E; Aragão, Luiz E O C

    2016-06-24

    In the Amazon region, the estimation of radiation fluxes through remote sensing techniques is hindered by the lack of ground measurements required as input in the models, as well as the difficulty to obtain cloud-free images. Here, we assess an approach to estimate net radiation (Rn) and its components under all-sky conditions for the Amazon region through the Surface Energy Balance Algorithm for Land (SEBAL) model utilizing only remote sensing and reanalysis data. The study period comprised six years, between January 2001-December 2006, and images from MODIS sensor aboard the Terra satellite and GLDAS reanalysis products were utilized. The estimates were evaluated with flux tower measurements within the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) project. Comparison between estimates obtained by the proposed method and observations from LBA towers showed errors between 12.5% and 16.4% and 11.3% and 15.9% for instantaneous and daily Rn, respectively. Our approach was adequate to minimize the problem related to strong cloudiness over the region and allowed to map consistently the spatial distribution of net radiation components in Amazonia. We conclude that the integration of reanalysis products and satellite data, eliminating the need for surface measurements as input model, was a useful proposition for the spatialization of the radiation fluxes in the Amazon region, which may serve as input information needed by algorithms that aim to determine evapotranspiration, the most important component of the Amazon hydrological balance.

  4. Fire as a Factor of Variation of Soil Respiration in Amazonia of Peru

    Science.gov (United States)

    Suarez, L.; Kruijt, B.

    2007-05-01

    Severe changes are affecting the role of Amazonia in the Earth system. One of these possible effects could be the modification of the relevance of soil in the carbon cycle. In this sense, fire is an important factor for mobilizing C from the soil to the atmosphere, mainly as CO2. This could have an important effect in the global warming. Our proposal will evaluate the variation of the soil respiration related to the seasonality and the fire effects on soils in the Amazonia of Peru and Brasil. In experimental parcels of four locations of Peru with different vegetation cover (forest and pasture), we will measure soil respiration along with the organic carbon and the microbial biomass of soils during campaigns of wet and dry seasons, with complementary measurements of soil temperature, water and nutrient content. Also, we will reproduce a fire experiment simulating local activity of "slash and burn" to evaluate fire effects. Measurements will be taken after the soil cooled and 1, 3, 5, 7 and 10 days after the fire. Additionally, the carbon stock of the subparcels will be evaluated. Evaluation of the variations of CO2 fluxes and the capacity of adaptation to fire and water content will be done through the comparisons of the different locations, type of soils and concentration of available N as an indicator of nutrient content.

  5. Dynamic Mesoscale Land-Atmosphere Feedbacks in Fragmented Forests in Amazonia

    Science.gov (United States)

    Rastogi, D.; Baidya Roy, S.

    2011-12-01

    This paper investigates land-atmosphere feedbacks in disturbed rainforests of Amazonia. Deforestation along the rapidly expanding highways and road network has created the unique fishbone land cover pattern in Rondonia, a state in southwestern Amazonia. Numerical experiments and observations show that sharp gradients in land cover due to the fishbone heterogeneity triggers mesoscale circulations. These circulations significantly change the spatial pattern of local hydrometeorology, especially convection, clouds and precipitation. The primary research question now is can these changes in local hydrometeorology affect vegetation growth in the clearings. If so, that would be a clear indication that land-atmosphere feedbacks can affect vegetation recovery in fragmented forests. A computationally-efficient modeling tool consisting of a mesoscale atmospheric model dynamically coupled with a plant growth model has been specifically developed to identify the atmospheric feedback pathways. Preliminary experiments focus on the seasonal-scale feedbacks during the dry season. Results show that temperature, incoming shortwave and precipitation are the three primary drivers through which the feedbacks operate. Increasing temperature increases respiratory losses generating a positive feedback. Increased cloud cover reduces incoming PAR and photosynthesis, resulting in a positive feedback. Increased precipitation reduces water stress and promotes growth resulting in a negative feedback. The net effect is a combination of these 3 feedback loops. These findings can significantly improve our understanding of ecosystem resiliency in disturbed tropical forests.

  6. Economically important species dominate aboveground carbon storage in forests of southwestern Amazonia

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    N. Galia Selaya

    2017-06-01

    Full Text Available Tree species in tropical forests provide economically important goods and ecosystem services. In submontane forests of southwestern Amazonia, we investigated the degree to which tree species important for subsistence and trade contribute to aboveground carbon storage (AGC. We used 41 1-hectare plots to determine the species abundance, basal area, and AGC of stems > 10 cm diameter at breast height (dbh. Economically important taxa were classified using ethnobotanical studies and according to their stem density. These taxa (n = 263 accounted for 45% of total stems, 53% of total basal area, and 56% of total AGC, significantly more than taxa with minor or unknown uses (Welch test at p 40 cm and few stems in regeneration classes of dbh < 10 to 20 cm (e.g., Bertholletia excelsa, Cariniana spp., Cedrelinga spp., Ceiba spp., Dipteryx spp., whereas dominant Tetragastris spp., and Pseudolmedia spp. had most stems in low diameter classes and a median diameter of < 30 cm. Bertholletia excelsa, with 1.5 stems per hectare, showed the highest basal area of any species and accounted for 9% of AGC (11 Mg/ha, twice that of the second-ranking species. Our study shows that economic importance and carbon stocks in trees are closely linked in southwestern Amazonia. Unplanned harvests can disrupt synergistic dual roles altering carbon stocks temporally or permanently. Precautionary measures based on species ecology, demography, and regeneration traits should be at the forefront of REDD+ to reconcile maximum harvesting limits, biodiversity conservation, and sustainable forest management.

  7. Arsenic, manganese and aluminum contamination in groundwater resources of Western Amazonia (Peru).

    Science.gov (United States)

    de Meyer, Caroline M C; Rodríguez, Juan M; Carpio, Edward A; García, Pilar A; Stengel, Caroline; Berg, Michael

    2017-12-31

    This paper presents a first integrated survey on the occurrence and distribution of geogenic contaminants in groundwater resources of Western Amazonia in Peru. An increasing number of groundwater wells have been constructed for drinking water purposes in the last decades; however, the chemical quality of the groundwater resources in the Amazon region is poorly studied. We collected groundwater from the regions of Iquitos and Pucallpa to analyze the hydrochemical characteristics, including trace elements. The source aquifer of each well was determined by interpretation of the available geological information, which identified four different aquifer types with distinct hydrochemical properties. The majority of the wells in two of the aquifer types tap groundwater enriched in aluminum, arsenic, or manganese at levels harmful to human health. Holocene alluvial aquifers along the main Amazon tributaries with anoxic, near pH-neutral groundwater contained high concentrations of arsenic (up to 700μg/L) and manganese (up to 4mg/L). Around Iquitos, the acidic groundwater (4.2≤pH≤5.5) from unconfined aquifers composed of pure sand had dissolved aluminum concentrations of up to 3.3mg/L. Groundwater from older or deeper aquifers generally was of good chemical quality. The high concentrations of toxic elements highlight the urgent need to assess the groundwater quality throughout Western Amazonia. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Evaluating the effect of nutrient redistribution by animals on the phosphorus cycle of lowland Amazonia

    Science.gov (United States)

    Buendía, Corina; Kleidon, Axel; Manzoni, Stefano; Reu, Björn; Porporato, Amilcare

    2018-01-01

    Phosphorus (P) availability decreases with soil age and potentially limits the productivity of ecosystems growing on old and weathered soils. Despite growing on ancient soils, ecosystems of lowland Amazonia are highly productive and are among the most biodiverse on Earth. P eroded and weathered in the Andes is transported by the rivers and deposited in floodplains of the lowland Amazon basin creating hotspots of P fertility. We hypothesize that animals feeding on vegetation and detritus in these hotspots may redistribute P to P-depleted areas, thus contributing to dissipate the P gradient across the landscape. Using a mathematical model, we show that animal-driven spatial redistribution of P from rivers to land and from seasonally flooded to terra firme (upland) ecosystems may sustain the P cycle of Amazonian lowlands. Our results show how P imported to land by terrestrial piscivores in combination with spatial redistribution of herbivores and detritivores can significantly enhance the P content in terra firme ecosystems, thereby highlighting the importance of food webs for the biogeochemical cycling of Amazonia.

  9. Factors that affect riverines territorial behavior on fishing environments in flooding areas, Low Solimões, Central Amazonia, Brazil

    Directory of Open Access Journals (Sweden)

    Jorge Iván Sánchez-Botero

    2010-12-01

    Full Text Available Flooding areas present high biological productivity and are inhabited by populations that practice agriculture-fishing activities, based on the multiple use of resources. The economicity of the system leads the riverines to territorial appropriation and the common dependence of the resources leads to the establishment of internal agreements, defining criteria of access and intensity of extraction. This study, through 244 interviews with fishermen and meetings at 16 communities of Low Solimões River, identified factors that influence on the magnitude and purpose of the fisheries, especially at common use fishing spots, describing appropriation mechanisms and conflicts. The studied area comprehends two systems of terra firme and one of flooding lakes. For subsistence and commercial fisheries was estimated the area, extension, and frequency of use for period of the year (dry/flood. Each community explored the fishing environments depending on the proximity and/or accessibility, revealing uses inside its territorial delimitations, with superposing on that explored for subsistence and commercial means. There are conflicts with commercial and sporting fisheries, fishermen out from the region and farmers. Prohibitions or access control don't exist to the igapós systems, but informal rules regulating the use. Three sceneries are proposed for the integrated management of the systems in the area, due to the diversity of environments and interests of the involved groups.

  10. Resilience of a cerradão subjected to intermediate disturbance in the Cerrado-Amazonia transition, Mato Grosso, Brazil

    Directory of Open Access Journals (Sweden)

    Ben Hur Marimon-Junior

    2013-09-01

    Full Text Available The present study examined the hypothesis that remnant forests in small protected areas may be resilient to intermediate disturbances. We analyzed the diameter and height distributions of the tree community in a typical cerradão (14°42’02.3”S and 52°21’02.6”W and determined which species were most abundant, sampling at two- to three-year intervals over eight years. In 2002, 2005, 2008 and 2010, we measured all live trees with a diameter ≥ 5 cm at 0.3 m above ground in 50 plots of 10 x 10 m. Although significant variation was observed in the density of the trees and the distributions of their diameters and heights, the community maintained the “reverse-J” and unimodal patterns for these distributions, respectively. These results indicate continuous recruitment and little change in the structure of the community over the study period, supporting our hypothesis. Three different patterns of diametric distribution were observed among the analyzed species, likely reflecting different forest occupation strategies. Hirtella glandulosa was the speciesmost able to exploit its environment, as it possessed the greatest overall abundance and was represented by individuals in all diameter classes.

  11. Prevalence and risk factors of ectoparasitic skin diseases and dermatomycoses in a rural community in Amazonia, Brazil

    OpenAIRE

    Lütkepohl, Anna-Caroline

    2016-01-01

    Infectious dermatoses such as ectoparasitoses and dermatomycoses are globally associated with morbidity, loss of income and social exclusion. Their distribution in society is inhomogeneous with a disproportionately high burden in socioeconomically disadvantaged groups, particularly in countries of the global South. However, little is known about the epidemiological determinants in these populations. This knowledge is essential for effective control measures. In order to generate meaning...

  12. A new species of Scinax from the Purus-Madeira interfluve, Brazilian Amazonia (Anura, Hylidae

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    Miquéias Ferrão

    2017-10-01

    Full Text Available A new tree frog species of the genus Scinax from the interfluve between the Purus and Madeira rivers, Brazilian Amazonia, is described and illustrated. The new species is diagnosed by medium body size, snout truncate in dorsal view, ulnar and tarsal tubercles absent, nuptial pads poorly developed, skin on dorsum shagreen, dorsum light brown with dark brown spots and markings, white groin with black spots, anterior and posterior surfaces of thighs black, and iris bright orange. The advertisement call consists of a single short note, with 16−18 pulses and dominant frequency at 1572−1594 Hz. Tadpoles are characterized by body ovoid in dorsal view and triangular in lateral view, tail higher than body, oral disc located anteroventrally and laterally emarginated, dorsum of body uniformly grey-brown with dark brown eye-snout stripe in preservative, fins translucent with small to large irregular diffuse dark brown spots.

  13. Impact of the Education Continues in Teachers of the UNAE Amazonia, Equator

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    Madelin Rodríguez Rensoli

    2017-08-01

    Full Text Available The objective of the present study is to socialize the research results obtained in the evaluation of attitudes, values and emotional states in teachers who went through the Continued Education Program developed by UNAE Amazonia. Semantic Differential Tables (TDS were used to identify the positive changes that were taking place in them during the implementation of innovative methodological strategies in teaching and learning. To achieve a positive change of the teacher to be involved in processes of changes in their pedagogical practice implied a permanent accompaniment in the identification of the problems that were faced, as well as in the design and implementation of alternative solutions according to the requirements of the new Curriculum oriented by the Ministry of Education in the country.

  14. Deforestation and climate feedbacks threaten the ecological integrity of south-southeastern Amazonia.

    Science.gov (United States)

    Coe, Michael T; Marthews, Toby R; Costa, Marcos Heil; Galbraith, David R; Greenglass, Nora L; Imbuzeiro, Hewlley M A; Levine, Naomi M; Malhi, Yadvinder; Moorcroft, Paul R; Muza, Michel Nobre; Powell, Thomas L; Saleska, Scott R; Solorzano, Luis A; Wang, Jingfeng

    2013-06-05

    A mosaic of protected areas, including indigenous lands, sustainable-use production forests and reserves and strictly protected forests is the cornerstone of conservation in the Amazon, with almost 50 per cent of the region now protected. However, recent research indicates that isolation from direct deforestation or degradation may not be sufficient to maintain the ecological integrity of Amazon forests over the next several decades. Large-scale changes in fire and drought regimes occurring as a result of deforestation and greenhouse gas increases may result in forest degradation, regardless of protected status. How severe or widespread these feedbacks will be is uncertain, but the arc of deforestation in south-southeastern Amazonia appears to be particularly vulnerable owing to high current deforestation rates and ecological sensitivity to climate change. Maintaining forest ecosystem integrity may require significant strengthening of forest conservation on private property, which can in part be accomplished by leveraging existing policy mechanisms.

  15. Evaluating the impact of distance measures on deforestation simulations in the fluvial landscapes of amazonia.

    Science.gov (United States)

    Salonen, Maria; Maeda, Eduardo Eiji; Toivonen, Tuuli

    2014-10-01

    Land use and land cover change (LUCC) models frequently employ different accessibility measures as a proxy for human influence on land change processes. Here, we simulate deforestation in Peruvian Amazonia and evaluate different accessibility measures as LUCC model inputs. We demonstrate how the selection, and different combinations, of accessibility measures impact simulation results. Out of the individual measures, time distance to market center catches the essential aspects of accessibility in our study area. The most accurate simulation is achieved when time distance to market center is used in association with distance to transport network and additional landscape variables. Although traditional Euclidean measures result in clearly lower simulation accuracy when used separately, the combination of two complementary Euclidean measures enhances simulation accuracy significantly. Our results highlight the need for site and context sensitive selection of accessibility variables. More sophisticated accessibility measures can potentially improve LUCC models' spatial accuracy, which often remains low.

  16. Widespread Forest Vertebrate Extinctions Induced by a Mega Hydroelectric Dam in Lowland Amazonia.

    Science.gov (United States)

    Benchimol, Maíra; Peres, Carlos A

    2015-01-01

    Mega hydropower projects in tropical forests pose a major emergent threat to terrestrial and freshwater biodiversity worldwide. Despite the unprecedented number of existing, under-construction and planned hydroelectric dams in lowland tropical forests, long-term effects on biodiversity have yet to be evaluated. We examine how medium and large-bodied assemblages of terrestrial and arboreal vertebrates (including 35 mammal, bird and tortoise species) responded to the drastic 26-year post-isolation history of archipelagic alteration in landscape structure and habitat quality in a major hydroelectric reservoir of Central Amazonia. The Balbina Hydroelectric Dam inundated 3,129 km2 of primary forests, simultaneously isolating 3,546 land-bridge islands. We conducted intensive biodiversity surveys at 37 of those islands and three adjacent continuous forests using a combination of four survey techniques, and detected strong forest habitat area effects in explaining patterns of vertebrate extinction. Beyond clear area effects, edge-mediated surface fire disturbance was the most important additional driver of species loss, particularly in islands smaller than 10 ha. Based on species-area models, we predict that only 0.7% of all islands now harbor a species-rich vertebrate assemblage consisting of ≥80% of all species. We highlight the colossal erosion in vertebrate diversity driven by a man-made dam and show that the biodiversity impacts of mega dams in lowland tropical forest regions have been severely overlooked. The geopolitical strategy to deploy many more large hydropower infrastructure projects in regions like lowland Amazonia should be urgently reassessed, and we strongly advise that long-term biodiversity impacts should be explicitly included in pre-approval environmental impact assessments.

  17. Widespread Forest Vertebrate Extinctions Induced by a Mega Hydroelectric Dam in Lowland Amazonia.

    Directory of Open Access Journals (Sweden)

    Maíra Benchimol

    Full Text Available Mega hydropower projects in tropical forests pose a major emergent threat to terrestrial and freshwater biodiversity worldwide. Despite the unprecedented number of existing, under-construction and planned hydroelectric dams in lowland tropical forests, long-term effects on biodiversity have yet to be evaluated. We examine how medium and large-bodied assemblages of terrestrial and arboreal vertebrates (including 35 mammal, bird and tortoise species responded to the drastic 26-year post-isolation history of archipelagic alteration in landscape structure and habitat quality in a major hydroelectric reservoir of Central Amazonia. The Balbina Hydroelectric Dam inundated 3,129 km2 of primary forests, simultaneously isolating 3,546 land-bridge islands. We conducted intensive biodiversity surveys at 37 of those islands and three adjacent continuous forests using a combination of four survey techniques, and detected strong forest habitat area effects in explaining patterns of vertebrate extinction. Beyond clear area effects, edge-mediated surface fire disturbance was the most important additional driver of species loss, particularly in islands smaller than 10 ha. Based on species-area models, we predict that only 0.7% of all islands now harbor a species-rich vertebrate assemblage consisting of ≥80% of all species. We highlight the colossal erosion in vertebrate diversity driven by a man-made dam and show that the biodiversity impacts of mega dams in lowland tropical forest regions have been severely overlooked. The geopolitical strategy to deploy many more large hydropower infrastructure projects in regions like lowland Amazonia should be urgently reassessed, and we strongly advise that long-term biodiversity impacts should be explicitly included in pre-approval environmental impact assessments.

  18. Interactions between rainfall, deforestation and fires during recent years in the Brazilian Amazonia.

    Science.gov (United States)

    Aragão, Luiz Eduardo O C; Malhi, Yadvinder; Barbier, Nicolas; Lima, Andre; Shimabukuro, Yosio; Anderson, Liana; Saatchi, Sassan

    2008-05-27

    Understanding the interplay between climate and land-use dynamics is a fundamental concern for assessing the vulnerability of Amazonia to climate change. In this study, we analyse satellite-derived monthly and annual time series of rainfall, fires and deforestation to explicitly quantify the seasonal patterns and relationships between these three variables, with a particular focus on the Amazonian drought of 2005. Our results demonstrate a marked seasonality with one peak per year for all variables analysed, except deforestation. For the annual cycle, we found correlations above 90% with a time lag between variables. Deforestation and fires reach the highest values three and six months, respectively, after the peak of the rainy season. The cumulative number of hot pixels was linearly related to the size of the area deforested annually from 1998 to 2004 (r2=0.84, p=0.004). During the 2005 drought, the number of hot pixels increased 43% in relation to the expected value for a similar deforested area (approx. 19000km2). We demonstrated that anthropogenic forcing, such as land-use change, is decisive in determining the seasonality and annual patterns of fire occurrence. Moreover, droughts can significantly increase the number of fires in the region even with decreased deforestation rates. We may expect that the ongoing deforestation, currently based on slash and burn procedures, and the use of fires for land management in Amazonia will intensify the impact of droughts associated with natural climate variability or human-induced climate change and, therefore, a large area of forest edge will be under increased risk of fires.

  19. Trying to Learn Lessons for Response to Extreme Events: Paradigm Shifts Affecting Civil Defense in the Trinational Region of Southwestern Amazonia

    Science.gov (United States)

    Santos, G. L. P.

    2015-12-01

    The last ten years have seen several extreme climate events in southwestern Amazonia with historic impacts. The City of Rio Branco, Capital of Acre, Brazil´s westernmost State, suffered its seventh consecutive annual flooding and its worst in March 2015. The city of Tarauacá, also in Acre, registered 12 flooding events between November 2014 and April 2015. The most recent flood of the trinational Acre River in 2015 set historic records for flood stage and number of displaced persons in Cobija, the Capital of Pando, Bolivia. From February to April 2014, floods of the Madeira River disrupted the one highway between Acre and southern Brazil. Puerto Maldonado, the capital in Madre de Dios Region of Peru had its worst flood in 50 years during 2014. In 2005 and 2010, prolonged droughts combined with ignition sources resulted in tens to hundreds of thousands of hectares of fire-damaged rainforests in the Madre de Dios, Acre and Pando (MAP) Region. The Civil Defenses in these three contiguous political units faced several abrupt paradigm shifts that affected their responses: 1) The drought of 2005 showed dramatically that regional rainforests do burn; 2) The recent flooding history, particularly in 2012 and 2015, demolished the cultural icon of a nine-year recurrence interval; 3) What happens outside your territory can be devastating. The Madeira River flood impeded an estimated 200 million dollars from circulating in Acre; 4) The past can be a terrible guide. For Cobija and Rio Branco, the 2015 flood was on the order of a meter higher than any other. Many home dwellers did not evacuate in time because they used past floods as a guide; 5) A collapse in communication - cell phones, land lines, and Internet - can get worse. In 2012, such a collapse occurred in two border towns for 5 days, yet in 2015 it lasted more than 11 days. Research is needed to address how institutions linked to Civil Defense can shift paradigms in time to be more effective.

  20. Spatial variability of the direct radiative forcing of biomass burning aerosols and the effects of land use change in Amazonia

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    E. T. Sena

    2013-02-01

    Full Text Available This paper addresses the Amazonian shortwave radiative budget over cloud-free conditions after considering three aspects of deforestation: (i the emission of aerosols from biomass burning due to forest fires; (ii changes in surface albedo after deforestation; and (iii modifications in the column water vapour amount over deforested areas. Simultaneous Clouds and the Earth's Radiant Energy System (CERES shortwave fluxes and aerosol optical depth (AOD retrievals from the Moderate Resolution Imaging SpectroRadiometer (MODIS were analysed during the peak of the biomass burning seasons (August and September from 2000 to 2009. A discrete-ordinate radiative transfer (DISORT code was used to extend instantaneous remote sensing radiative forcing assessments into 24-h averages.

    The mean direct radiative forcing of aerosols at the top of the atmosphere (TOA during the biomass burning season for the 10-yr studied period was −5.6 ± 1.7 W m−2. Furthermore, the spatial distribution of the direct radiative forcing of aerosols over Amazonia was obtained for the biomass burning season of each year. It was observed that for high AOD (larger than 1 at 550 nm the maximum daily direct aerosol radiative forcing at the TOA may be as high as −20 W m−2 locally. The surface reflectance plays a major role in the aerosol direct radiative effect. The study of the effects of biomass burning aerosols over different surface types shows that the direct radiative forcing is systematically more negative over forest than over savannah-like covered areas. Values of −15.7 ± 2.4 W m−2τ550 nm and −9.3 ± 1.7 W m−2τ550 nm were calculated for the mean daily aerosol forcing efficiencies over forest and savannah-like vegetation respectively. The overall mean annual land use change radiative forcing due to deforestation over the state of Rondônia, Brazil, was determined as −7.3 ± 0.9 W m

  1. Biogeographic and diversification patterns of Neotropical Troidini butterflies (Papilionidae support a museum model of diversity dynamics for Amazonia

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    Condamine Fabien L

    2012-06-01

    Full Text Available Abstract Background The temporal and geographical diversification of Neotropical insects remains poorly understood because of the complex changes in geological and climatic conditions that occurred during the Cenozoic. To better understand extant patterns in Neotropical biodiversity, we investigated the evolutionary history of three Neotropical swallowtail Troidini genera (Papilionidae. First, DNA-based species delimitation analyses were conducted to assess species boundaries within Neotropical Troidini using an enlarged fragment of the standard barcode gene. Molecularly delineated species were then used to infer a time-calibrated species-level phylogeny based on a three-gene dataset and Bayesian dating analyses. The corresponding chronogram was used to explore their temporal and geographical diversification through distinct likelihood-based methods. Results The phylogeny for Neotropical Troidini was well resolved and strongly supported. Molecular dating and biogeographic analyses indicate that the extant lineages of Neotropical Troidini have a late Eocene (33–42 Ma origin in North America. Two independent lineages (Battus and Euryades + Parides reached South America via the GAARlandia temporary connection, and later became extinct in North America. They only began substantive diversification during the early Miocene in Amazonia. Macroevolutionary analysis supports the “museum model” of diversification, rather than Pleistocene refugia, as the best explanation for the diversification of these lineages. Conclusions This study demonstrates that: (i current Neotropical biodiversity may have originated ex situ; (ii the GAARlandia bridge was important in facilitating invasions of South America; (iii colonization of Amazonia initiated the crown diversification of these swallowtails; and (iv Amazonia is not only a species-rich region but also acted as a sanctuary for the dynamics of this diversity. In particular, Amazonia probably allowed

  2. Biogeographic and diversification patterns of Neotropical Troidini butterflies (Papilionidae) support a museum model of diversity dynamics for Amazonia.

    Science.gov (United States)

    Condamine, Fabien L; Silva-Brandão, Karina L; Kergoat, Gael J; Sperling, Felix A H

    2012-06-12

    The temporal and geographical diversification of Neotropical insects remains poorly understood because of the complex changes in geological and climatic conditions that occurred during the Cenozoic. To better understand extant patterns in Neotropical biodiversity, we investigated the evolutionary history of three Neotropical swallowtail Troidini genera (Papilionidae). First, DNA-based species delimitation analyses were conducted to assess species boundaries within Neotropical Troidini using an enlarged fragment of the standard barcode gene. Molecularly delineated species were then used to infer a time-calibrated species-level phylogeny based on a three-gene dataset and Bayesian dating analyses. The corresponding chronogram was used to explore their temporal and geographical diversification through distinct likelihood-based methods. The phylogeny for Neotropical Troidini was well resolved and strongly supported. Molecular dating and biogeographic analyses indicate that the extant lineages of Neotropical Troidini have a late Eocene (33-42 Ma) origin in North America. Two independent lineages (Battus and Euryades+Parides) reached South America via the GAARlandia temporary connection, and later became extinct in North America. They only began substantive diversification during the early Miocene in Amazonia. Macroevolutionary analysis supports the "museum model" of diversification, rather than Pleistocene refugia, as the best explanation for the diversification of these lineages. This study demonstrates that: (i) current Neotropical biodiversity may have originated ex situ; (ii) the GAARlandia bridge was important in facilitating invasions of South America; (iii) colonization of Amazonia initiated the crown diversification of these swallowtails; and (iv) Amazonia is not only a species-rich region but also acted as a sanctuary for the dynamics of this diversity. In particular, Amazonia probably allowed the persistence of old lineages and contributed to the steady

  3. Maximizing Amazonia's Ecosystem Services: Juggling the potential for carbon storage, agricultural yield and biodiversity in the Amazon

    Science.gov (United States)

    O'Connell, C. S.; Foley, J. A.; Gerber, J. S.; Polasky, S.

    2011-12-01

    The Amazon is not only an exceptionally biodiverse and carbon-rich tract of tropical forest, it is also a case study in land use change. Over the next forty years it will continue to experience pressure from an urbanizing and increasingly affluent populace: under a business-as-usual scenario, global cropland, pasture and biofuels systems will carry on expanding, while the Amazon's carbon storage potential will likely become another viable revenue source under REDD+. Balancing those competing land use pressures ought also take into account Amazonia's high - but heterogeneous - biodiversity. Knowing where Amazonia has opportunities to make efficient or optimal trade offs between carbon storage, agricultural production and biodiversity can allow policymakers to direct or influence LUC drivers. This analysis uses a spatially-explicit model that takes climate and management into account to quantify the potential agricultural yield of both the Amazon's most important agricultural commodities - sugar, soy and maize - as well as several that are going to come into increasing prominence, including palm oil. In addition, it maps the potential for carbon to be stored in forest biomass and relative species richness across Amazonia. We then compare carbon storage, agricultural yield and species richness and identify areas where efficient trade offs occur between food, carbon, and biodiversity - three critical ecosystem goods and services provided by the world's largest tropical forest.

  4. Preferência do pulgão-preto e da cigarrinha-verde em diferentes genótipos de feijão-caupi em Roraima = Preference of the black aphid and green leafhopper in different genotypes of cowpea in Roraima, Brazil

    Directory of Open Access Journals (Sweden)

    Hugo Falkyner da Silva Bandeira

    2015-03-01

    Full Text Available A ocorrência de insetos praga está entre os fatores que mais afetam a produtividade do feijão-caupi. Objetivou-se, com este trabalho, avaliar a resistência de nove genótipos de feijão-caupi ao ataque do pulgão-preto, Aphis craccivora Koch, 1854, e da cigarrinha-verde, (Empoasca sp., e a flutuação populacional de A. craccivora sobre a cultura, em condições de campo. Foram selecionados nove genótipos de feijão-caupi (Vigna unguiculata (L. Walp, a saber: BR-17 Gurgueia, BRS Guariba, BRS Cauamé, Pretinho Precoce 1, UFRR Grão Verde, Apiaú, Iracema, Cara-Preta e Sempre Verde. O delineamento experimental foi realizado em blocos casualizados, em esquema de parcela subdividida, com quatro repetições. Cada variedade foi plantada em quatro linhas paralelas, considerando as duas fileiras centrais como área útil. A contagem dos pulgões foi feita diretamente na última folha trifoliolada completamente aberta, enquanto que a das cigarrinhas foi realizada pelo método da batida de plantas em bandeja com água. Nos genótipos BRS Cauamé, BRS Guariba e Pretinho Precoce 1 foram observados os menores índices de infestação por A. craccivora, apresentando, portanto, resistência do tipo não preferência em relação aos demais avaliados. O genótipo Apiaú mostrou-se suscetível a Empoasca sp., e os BR-17 Gurgueia, Cara-Preta, Sempre Verde, UFRR Grão Verde e BRS Cauamé foram os mais resistentes, em função da menor preferência pelas cigarrinhas, registrada, principalmente, aos 28 e 35 dias após a emergência das plantas. = The occurrence of insect pests is among the most important factors affecting cowpea productivity. This study aimed at evaluating the resistance of nine genotypes of cowpea attack in black aphid Aphis craccivora Koch, 1854, and of green leafhopper (Empoasca sp., and the population fluctuation of A. craccivora on culture, under field conditions. Nine cowpea (Vigna unguiculata (L. Walp genotypes were chosen: BR-17 Gurgueia, BRS Guariba, BRS Cauamé, Pretinho Precoce 1, UFRR Grão Verde, Apiaú, Iracema, Cara-Preta, and Sempre Verde. The experimental design was carried out in randomized blocks with four replications. Each variety was planted in four parallel lines, considering the two central rows as the useful area. Counting of aphids-black was taken directly across the last fully open leaf, whereas the leafhoppers leaf stage was performed by the method of beating plants on tray with water. The genotypes BRS Cauamé, BRS Guariba, and Pretinho Precoce 1 had the lowest levels of infestation by A. craccivora, presenting, therefore, a nonpreference resistance compared to the others assessed. The genotype Apiaú was susceptible to Empoasca sp. and the genotypes BR-17 Gurgueia, Cara-Preta, Sempre Verde, UFRR Grão Verde, and BRS Cauamé were the most resistant, since they were least preferred by leafhoppers at 28 and 35 days after plant emergence.

  5. Identificação de áreas de estratificação epidemiológica no foco de oncocercose na região Yanomami, Roraima, Brasil Identifying areas of epidemiological stratification in an onchocerciasis focus in Yanomami territory, Roraima, Brazil

    Directory of Open Access Journals (Sweden)

    Giovanini Evelim Coelho

    1998-07-01

    Full Text Available No presente trabalho, visando a um adequado planejamento, análise e acompanhamento do Programa de Tratamento, Controle e Eliminação da Oncocercose Humana no Brasil, foram estudadas 27 áreas geográficas e examinados 3.974 indivíduos. Assim, foram identificadas e estratificadas quatro áreas epidemiológicas, tendo por base as prevalências diferenciadas em cada uma delas.In this paper, aimed at suitable planning, analysis, and follow-up of treatment, control, and eradication in a human onchocerciasis program, were studied 27 geographic areas and examined 3,974 inhabitants. Four epidemiological areas with different prevalences were identified and stratified.

  6. Datafile: Brazil

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    There is as yet little to show for the enormous investment made by Brazil over the past 20 years in nuclear power and the fuel cycle. The only nuclear power plant (657MWe PWR) in operation has had a poor performance record and the two reactors (1309MWe PWRs) under construction are more than ten years behind the original schedule. Aspirations of building commercial fuel cycle facilities have proved extremely optimistic. In the latest reorganization of the industry, the construction and operation of nuclear power stations is entrusted to the national utility and the various civilian/military R and D efforts in the fuel cycle are being integrated under civilian supervision. This should lead to greater accountability and efficiency in the future. (author)

  7. Seasonal variation of ozone deposition to a tropical rain forest in southwest Amazonia

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    U. Rummel

    2007-10-01

    Full Text Available Within the project EUropean Studies on Trace gases and Atmospheric CHemistry as a contribution to Large-scale Biosphere-atmosphere experiment in Amazonia (LBA-EUSTACH, we performed tower-based eddy covariance measurements of O3 flux above an Amazonian primary rain forest at the end of the wet and dry season. Ozone deposition revealed distinct seasonal differences in the magnitude and diel variation. In the wet season, the rain forest was an effective O3 sink with a mean daytime (midday maximum deposition velocity of 2.3 cm s−1, and a corresponding O3 flux of −11 nmol m−2 s−1. At the end of the dry season, the ozone mixing ratio was about four times higher (up to maximum values of 80 ppb than in the wet season, as a consequence of strong regional biomass burning activity. However, the typical maximum daytime deposition flux was very similar to the wet season. This results from a strong limitation of daytime O3 deposition due to reduced plant stomatal aperture as a response to large values of the specific humidity deficit. As a result, the average midday deposition velocity in the dry burning season was only 0.5 cm s−1. The large diel ozone variation caused large canopy storage effects that masked the true diel variation of ozone deposition mechanisms in the measured eddy covariance flux, and for which corrections had to be made. In general, stomatal aperture was sufficient to explain the largest part of daytime ozone deposition. However, during nighttime, chemical reaction with nitrogen monoxide (NO was found to contribute substantially to the O3 sink in the rain forest canopy. Further contributions were from non-stomatal plant uptake and other processes that could not be clearly identified.

    Measurements, made simultaneously on a 22 years old cattle pasture enabled the spatially and temporally direct comparison of O3

  8. Land cover change interacts with drought severity to change fire regimes in Western Amazonia.

    Science.gov (United States)

    Gutiérrez-Vélez, Víctor H; Uriarte, María; DeFries, Ruth; Pinedo-Vásquez, Miguel; Fernandes, Katia; Ceccato, Pietro; Baethgen, Walter; Padoch, Christine

    Fire is becoming a pervasive driver of environmental change in Amazonia and is expected to intensify, given projected reductions in precipitation and forest cover. Understanding of the influence of post-deforestation land cover change on fires in Amazonia is limited, even though fires in cleared lands constitute a threat for ecosystems, agriculture, and human health. We used MODIS satellite data to map burned areas annually between 2001 and 2010. We then combined these maps with land cover and climate information to understand the influence of land cover change in cleared lands and dry-season severity on fire occurrence and spread in a focus area in the Peruvian Amazon. Fire occurrence, quantified as the probability of burning of individual 232-m spatial resolution MODIS pixels, was modeled as a function of the area of land cover types within each pixel, drought severity, and distance to roads. Fire spread, quantified as the number of pixels burned in 3 × 3 pixel windows around each focal burned pixel, was modeled as a function of land cover configuration and area, dry-season severity, and distance to roads. We found that vegetation regrowth and oil palm expansion are significantly correlated with fire occurrence, but that the magnitude and sign of the correlation depend on drought severity, successional stage of regrowing vegetation, and oil palm age. Burning probability increased with the area of nondegraded pastures, fallow, and young oil palm and decreased with larger extents of degraded pastures, secondary forests, and adult oil palm plantations. Drought severity had the strongest influence on fire occurrence, overriding the effectiveness of secondary forests, but not of adult plantations, to reduce fire occurrence in severely dry years. Overall, irregular and scattered land cover patches reduced fire spread but irregular and dispersed fallows and secondary forests increased fire spread during dry years. Results underscore the importance of land cover

  9. Seasonal dynamics of Aedes aegypti (Diptera: Culicidae in the northernmost state of Brazil: a likely port-of-entry for dengue virus 4

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    Cláudia Torres Codeço

    2009-07-01

    Full Text Available Roraima is the northernmost state of Brazil, bordering both Venezuela and Guyana. Appropriate climate and vector conditions for dengue transmission together with its proximity to countries where all four dengue serotypes circulate make this state, particularly the capital Boa Vista, strategically important for dengue surveillance in Brazil. Nonetheless, few studies have addressed the population dynamics of Aedes aegypti in Boa Vista. In this study, we report temporal and spatial variations in Ae. aegypti population density using ovitraps in two highly populated neighbourhoods; Centro and Tancredo Neves. In three out of six surveys, Ae. aegypti was present in more than 80% of the sites visited. High presence levels of this mosquito suggest ubiquitous human exposure to the vector, at least during part of the year. The highest infestation rates occurred during the peak of the rainy seasons, but a large presence was also observed during the early dry season (although with more variation among years. Spatial distribution of positive houses changed from a sparse and local pattern to a very dense pattern during the dry-wet season transition. These results suggest that the risk of dengue transmission and the potential for the new serotype invasions are high for most of the year.

  10. Envia garciai, a new genus and species of mygalomorph spiders (Araneae, Microstigmatidae from Brazilian Amazonia

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    Ott Ricardo

    2003-01-01

    Full Text Available The genus Envia, comprising only the new species Envia garciai, is proposed. These small mygalomorph spiders were abundantly collected in soil cores and litter samples in primary rain forests near Manaus, Amazonas, Brazil.

  11. FATAL OUTCOME OF INFECTION BY DENGUE 4 IN A PATIENT WITH THROMBOCYTOPENIC PURPURA AS A COMORBID CONDITION IN BRAZIL

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    Frederico Figueiredo Amâncio

    2014-06-01

    Full Text Available Dengue is currently a major public-health problem. Dengue virus (DENV is classified into four distinct serotypes, DENV 1-4. After 28 years of absence, DENV-4 was again detected in Brazil in 2010 in Roraima State, and one year later, the virus was identified in the northern Brazilian states of Amazonas and Pará, followed by Rio de Janeiro and São Paulo. In Minas Gerais, the first confirmed case of DENV-4 occurred in the municipality of Frutal in 2011 and has now been isolated from a growing number of patients. Although DENV-2 is associated with the highest risk of severe forms of the disease and death due to the infection, DENV-4 has also been associated with severe forms of the disease and an increasing risk of hemorrhagic manifestations. Herein, the first fatal case of confirmed DENV-4 in Brazil is reported. The patient was an 11-year-old girl from the municipality of Montes Claros in northern Minas Gerais State, Brazil. She had idiopathic thrombocytopenic purpura as a comorbid condition and presented with a fulminant course of infection, leading to death due to hemorrhagic complications. Diagnosis was confirmed by detection of Dengue-specific antibodies using IgM capture enzyme-linked immunosorbent assay and semi-nested RT-PCR. Primary care physicians and other health-care providers should bear in mind that DENV-4 can also result in severe forms of the disease and lead to hemorrhagic complications and death, mainly when dengue infection is associated with coexisting conditions.

  12. Functional diversity of bacterial genes associated with aromatic hydrocarbon degradation in anthropogenic dark earth of Amazonia

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    Mariana Gomes Germano

    2012-05-01

    Full Text Available The objective of this work was to evaluate the catabolic gene diversity for the bacterial degradation of aromatic hydrocarbons in anthropogenic dark earth of Amazonia (ADE and their biochar (BC. Functional diversity analyses in ADE soils can provide information on how adaptive microorganisms may influence the fertility of soils and what is their involvement in biogeochemical cycles. For this, clone libraries containing the gene encoding for the alpha subunit of aromatic ring-hydroxylating dioxygenases (α-ARHD bacterial gene were constructed, totaling 800 clones. These libraries were prepared from samples of an ADE soil under two different land uses, located at the Caldeirão Experimental Station - secondary forest (SF and agriculture (AG -, and the biochar (SF_BC and AG_BC, respectively. Heterogeneity estimates indicated greater diversity in BC libraries; and Venn diagrams showed more unique operational protein clusters (OPC in the SF_BC library than the ADE soil, which indicates that specific metabolic processes may occur in biochar. Phylogenetic analysis showed unidentified dioxygenases in ADE soils. Libraries containing functional gene encoding for the alpha subunit of the aromatic ring-hydroxylating dioxygenases (ARHD gene from biochar show higher diversity indices than those of ADE under secondary forest and agriculture.

  13. The trophic role of microbial loop in an Amazonia central floodplain lake

    International Nuclear Information System (INIS)

    Caraballo, Pedro; Forsberg, Bruce R; Leite, Rosseval G

    2012-01-01

    In order to evaluate the role of heterotrophic bacteria on carbon flow in food chains of an Amazonian floodplain lake, monthly collections of these organisms were made during the hydrological year from December 2007 to November 2008. Littoral, pelagic, and aquatic macrophyte regions of the Catalao Lake in central Amazonia were sampled and bacteria were multiplied in vitro, using dissolved organic carbon (COD) of each one of the regions studied as a substrate. The bacterial biomass obtained was used for stable isotope analyses of carbon and nitrogen. These data were confronted with COD values of the four hydrological periods of the lake (dry, rising, flood and fall). In general, it was found that the main source of carbon for heterotrophic bacteria was that of C4 origin, which presented a minimum contribution of 75% of bacterial biomass, to the extent that the bacteria D13C average value -17.72 Per Mille ± 2.25 was comparing this value with the D13C of zooplankton in the same period (-33.04 Per Mille ± 3.81) permit concludes that the contribution of heterotrophic bacteria in the carbon flow to higher trophic levels in the Catalao lake is minimal.

  14. Microbial diversity of an anoxic zone of a hydroelectric power station reservoir in Brazilian Amazonia.

    Science.gov (United States)

    Graças, Diego A; Miranda, Paulo R; Baraúna, Rafael A; McCulloch, John A; Ghilardi, Rubens; Schneider, Maria Paula C; Silva, Artur

    2011-11-01

    Microbial diversity was evaluated in an anoxic zone of Tucuruí Hydroelectric Power Station reservoir in Brazilian Amazonia using a culture-independent approach by amplifying and sequencing fragments of the 16S rRNA gene using metagenomic DNA as a template. Samples obtained from the photic, aphotic (40 m) and sediment (60 m) layers were used to construct six 16S rDNA libraries containing a total of 1,152 clones. The sediment, aphotic and photic layers presented 64, 33 and 35 unique archaeal operational taxonomic units (OTUs). The estimated richness of these layers was evaluated to be 153, 106 and 79 archaeal OTUs, respectively, using the abundance-based coverage estimator (ACE) and 114, 83 and 77 OTUs using the Chao1 estimator. For bacterial sequences, 114, 69 and 57 OTUs were found in the sediment, aphotic and photic layers, which presented estimated richnesses of 1,414, 522 and 197 OTUs (ACE) and 1,059, 1,014 and 148 OTUs (Chao1), respectively. Phylogenetic analyses of the sequences obtained revealed a high richness of microorganisms which participate in the carbon cycle, namely, methanogenic archaea and methanotrophic proteobacteria. Most sequences obtained belong to non-culturable prokaryotes. The present study offers the first glimpse of the huge microbial diversity of an anoxic area of a man-made lacustrine environment in the tropics.

  15. Population Development of Zabrotes subfasciatus (Coleoptera: Chrysomelidae) in Landrace Bean Varieties Occurring in Southwestern Amazonia.

    Science.gov (United States)

    Lopes, L M; Araújo, A E F; Santos, A C V; Santos, V B; Sousa, A H

    2016-02-01

    The common bean, Phaseolus vulgaris (L.), is one of the most important sources of protein worldwide, and Latin America is one of the recognized centers of diversity of this species. However, storage of this product after harvest is not feasible because of bruchid attacks. This study determined the accumulated normalized rate of emergence and the daily emergence rate of Zabrotes subfasciatus (Boheman) (Coleoptera: Chrysomelidae:Bruchinae) in five landrace varieties of common bean (BRL 01, SNA 01, RDR 01, RBC 01, and RBC 13) that occurin southwestern Amazonia. These varieties were selected for this study because they are well-distributed throughout the Amazonian communities. Beans of each variety were infested with 50 unsexed adults, and the insects were removed 13 d after beginning the bioassays. The adult progeny obtained from the feeding substrate were counted and removed every other day after the first emergence, until the end of the emergence period. Differences were observed in the calculated rates of development; however, the time required for development and emergence of the insects was independent. Of the five varieties of bean investigated, we observed that the RDR 01, BRL 01, and SNA 01 cultivars are resistant to Z. subfasciatus; the results indicate that the use of these three varieties can reduce problems associated with bruchid attacks and enable storage of the product after harvesting.

  16. [The fleas of mammals from the Ucayali River basin (the Peruvian Amazonia)].

    Science.gov (United States)

    Darskaia, N F; Malygin, V M

    1996-01-01

    The material collected from 57 specimens of 9 mammalian species in two localities of the Peruvian Amazonia includes 212 specimens of fleas belonging to four species (Polygenis klagesi, Ropalopsyllus lugubris, Rh. australis and Rothschildopsylla noctilionis). This is the first record of fleas in the Ucayali River basin. The majority of flea specimens were collected form three morphologically similar but karyotypically and electrophoretically distinct species of spiny rats of the genus Proechimys. These fleas belong to the species P. klagesi. The subspecies P. k. samuelis was collected from 32-chromosome spiny rats nearby Pucallpa (8 degrees 22' S, 74 degrees 43' W), whereas in the locality nearby the village Jenaro Errera (4 degrees 52' S, 73 degrees 39' W) only the nominative subspecies P. k. klagesi were collected from all three species of spiny rats. Other species of fleas have relatively less abundance. Six fleas Rh. l. lugubris were found on one specimen of Cuniculus paca; a single Rh. australis--on one specimen of Myoprocta pratti; and a single R. noctilionis--on one specimen of Eptesicus brasiliensis.

  17. Structuring of Milk Production Basins: Comparison between Brazilian Amazonia and Mali

    Directory of Open Access Journals (Sweden)

    R. Poccard Chapuis

    2007-01-01

    Full Text Available In Brazilian Amazonia, structuring of dairy basins is progressing fast. In Mali, these processes are not engaged, although the activity of cattle keeping is ancient and currently thriving. This difference covers essential stakes: fight against poverty, food production in the face of the demographic challenge, current debates on the theories of the development. The comparative analysis is based on a diachronic model of the successive phases of structuring of the Amazonian dairy basins. This model is then applied to dairy dynamics in Mali to identify blockages in the structuring of basins. Six phases are highlighted in the Amazonian model, from subsistence consumption of raw milk to basin specialization and establishment of an industrial monopoly. The application in Mali shows that the initial situations are similar (territory constraints. But two essential mechanisms are not working: transportation of finished products to distant markets, and fresh milk collection extended beyond the boundaries of the direct sale to urban consumers. These two aspects, essential to ensure the flow upstream and downstream of the products, address the question of dairy unit location as well as the distribution organization in Bamako. In spite of the limits of the comparative analysis, the model shows that the keys to a positive evolution in Mali are more to be found at the industry and distribution levels than at the production level. Public actions (State and collectivities could focus on these two points, notably through training activities and credit policies.

  18. Late Quaternary landscape evolution of northeastern Amazonia from pollen and diatom records

    Directory of Open Access Journals (Sweden)

    DARCILÉA F. CASTRO

    2013-03-01

    Full Text Available The main goal of this study was to reconstruct the Late Pleistocene-Holocene floristic composition in an area of the northern Brazilian Amazonia, comparing the results with other Amazonian localities in order to discuss the factors that have influenced phytophysiognomic changes over this time period. The work in eastern Marajó Island at the mouth of the Amazonas River was approached based on analysis of 98 pollen and diatom samples from core data distributed along a proximal to distal transect of a paleoestuarine system. The results indicated high concentration of Rhizophora, associated with arboreal pollen grains typical of the modern Amazonian rainforest during the last 40,000 cal yrs BP. Pollen composition also included wetland herbs. Diatoms were dominated by marine and fresh water taxa. Wetland forest, mangrove and, subordinately herbs remained constant during most of the latest Pleistocene-early/middle Holocene. At 5,000 cal yrs BP, there was a distinguished change from forest and mangrove to wet grassland savanna due to sea level fluctuation. As marine influence decreased, the estuary gave rise to fresh water lacustrine and swamp environments, with establishment of herbaceous campos. A main conclusion from this study is that solely the occurrence of herbaceous savanna can not be used as a definitive indicator of past dry climates in Amazonian areas.

  19. Megafans and Trumpeter Bird Biodiversity-Psophia Phylogeography and Landscape Evolution in Amazonia

    Science.gov (United States)

    Wilkinson, Justin

    2014-01-01

    Based on geomorphic character and mapped geology, geologists have interpreted the landscape surrounding the Andes Mountains as becoming progressively younger to the East. These sedimentary materials filled the late Miocene swampland that formerly occupied central and western Amazonia. Apart from the ancient landscapes of the Guiana Highlands (top right, figure 1a), Zone Ac is the oldest, followed by Zone Aw, within which megafan Jw is older than megafan Je (figure 1a). DNA-based paleogeography of the trumpeters shows that younger clades diverge from parent lineages with increasing distance from the Andes chain. Thus, Psophia napensis diverges from the P. crepitans parent, and P. ochroptera diverges from P. napensis. The P. ochroptera population is confined solely to the Je megafan (figure 1a). The same trend is seen on the south side of the Amazon depression. Since the timing of the events seems to be of exactly the same order [post-Miocene for the land surfaces and trumpeter divergence within the last 3 million years (figure 1d)], it seems reasonable to think that the megafans provided the substrate on which new bird lineages could speciate. Such physical controls of evolution are becoming more important in the understanding of biodiversity.

  20. The distribution and amount of carbon in the largest peatland complex in Amazonia

    International Nuclear Information System (INIS)

    Draper, Frederick C; Baker, Timothy R; Roucoux, Katherine H; Lawson, Ian T; Mitchard, Edward T A; Honorio Coronado, Euridice N; Zaráte, Ricardo; Lähteenoja, Outi; Torres Montenegro, Luis; Valderrama Sandoval, Elvis

    2014-01-01

    Peatlands in Amazonian Peru are known to store large quantities of carbon, but there is high uncertainty in the spatial extent and total carbon stocks of these ecosystems. Here, we use a multi-sensor (Landsat, ALOS PALSAR and SRTM) remote sensing approach, together with field data including 24 forest census plots and 218 peat thickness measurements, to map the distribution of peatland vegetation types and calculate the combined above- and below-ground carbon stock of peatland ecosystems in the Pastaza-Marañon foreland basin in Peru. We find that peatlands cover 35 600 ± 2133 km 2 and contain 3.14 (0.44–8.15) Pg C. Variation in peat thickness and bulk density are the most important sources of uncertainty in these values. One particular ecosystem type, peatland pole forest, is found to be the most carbon-dense ecosystem yet identified in Amazonia (1391 ± 710 Mg C ha −1 ). The novel approach of combining optical and radar remote sensing with above- and below-ground carbon inventories is recommended for developing regional carbon estimates for tropical peatlands globally. Finally, we suggest that Amazonian peatlands should be a priority for research and conservation before the developing regional infrastructure causes an acceleration in the exploitation and degradation of these ecosystems. (letter)

  1. Allometry and growth of six tree species in a terra firme forest in colombian amazonia

    International Nuclear Information System (INIS)

    Giraldo Pamplona Wilson A; Dairon, Alvaro; Cardenas Montoya J, Duque

    2011-01-01

    In this study carried out in the Amacayacu National Park in the Colombian Amazonia, we assessed the allometric relationship among different tree structural variables and the growth in diameter and biomass of six species classified according to their wood specific gravity. The tree species chosen were Eschweilera rufolia, Eschweilera itayensis, Conceveiba guianensis, Otoba parvifolia, Pseudolmedia laevis, and Apeiba aspera. The dbh was the most important structural explanatory variable. Regarding the total height dbh model, the allometric coefficient b changed between species showing a trend to increase, and thus a taper decrease, proportional to. There were o significant differences in diameter growth between species (P=0.119, F=1.80) or functional groups (P=0.153, F= 1.19). Likewise, biomass growth did not show significant differences neither between species (P=0.0784, F=2.05) nor functional groups (P=0.0711, F=2.71). However, there was a positive trend between and diameter growth and a negative one between and biomass growth. The results of this study suggest that this forest is recovering in biomass at a constant rate independent of the patch age, which emphasizes on the importance of pioneer species and gap formation on the carbon dynamics and the species coexistence in Amazonian tierra firme forests.

  2. Regional-Scale Drivers of Forest Structure and Function in Northwestern Amazonia

    Science.gov (United States)

    Higgins, Mark A.; Asner, Gregory P.; Anderson, Christopher B.; Martin, Roberta E.; Knapp, David E.; Tupayachi, Raul; Perez, Eneas; Elespuru, Nydia; Alonso, Alfonso

    2015-01-01

    Field studies in Amazonia have found a relationship at continental scales between soil fertility and broad trends in forest structure and function. Little is known at regional scales, however, about how discrete patterns in forest structure or functional attributes map onto underlying edaphic or geological patterns. We collected airborne LiDAR (Light Detection and Ranging) data and VSWIR (Visible to Shortwave Infrared) imaging spectroscopy measurements over 600 km2 of northwestern Amazonian lowland forests. We also established 83 inventories of plant species composition and soil properties, distributed between two widespread geological formations. Using these data, we mapped forest structure and canopy reflectance, and compared them to patterns in plant species composition, soils, and underlying geology. We found that variations in soils and species composition explained up to 70% of variation in canopy height, and corresponded to profound changes in forest vertical profiles. We further found that soils and plant species composition explained more than 90% of the variation in canopy reflectance as measured by imaging spectroscopy, indicating edaphic and compositional control of canopy chemical properties. We last found that soils explained between 30% and 70% of the variation in gap frequency in these forests, depending on the height threshold used to define gaps. Our findings indicate that a relatively small number of edaphic and compositional variables, corresponding to underlying geology, may be responsible for variations in canopy structure and chemistry over large expanses of Amazonian forest. PMID:25793602

  3. Chemical characterization of ancient pottery from the southwest Amazonia using neutron activation analysis

    International Nuclear Information System (INIS)

    Carvalho, Patricia R.; Munita, Casimiro S.; Neves, Eduardo G.; Zimpel, Carlos A.; Universidade de Sao Paulo

    2017-01-01

    The analyzes carried out in this work aims to contribute to the discussion about the ceramic objects founded in Monte Castelo's sambaqui located at Southwest Amazonia. The first study accomplished by Miller in 1980 suggests that this archaeological site is inserted in the old contexts of production of ceramics in the Amazon. Until today, there are not any physical and chemical analysis studies in this ceramics and this kind of studies may help archaeological studies performed at the sambaqui. With this purpose, this work presents a preliminary study of chemical characterization of eighty-seven ceramic samples using the Neutron Activation Analysis (NAA). The analyzed elements were: As, K, La, Lu, Na, Nd, Sm, U, Yb, Ce, Co, Cr, Cs, Eu, Fe, Hf, Rb, Sc, Ta, Tb, Th. With the purpose to study the similarity/dissimilarity between the samples cluster and discriminant analysis were used. The results showed the existence of three different chemical groups that are in agreement with the archaeological studies made by Miller which found a sequence of cultural development, with three main occupational components whose dating ranging from 8.400 to 4.000 b.P. In this way, the results of this work are in agreement with miller's studies and suggest Bacabal's phase as the oldest ceramist culture in the Southwest of the Amazon. (author)

  4. Lipid Oxidation Inhibitory Effects and Phenolic Composition of Aqueous Extracts from Medicinal Plants of Colombian Amazonia

    Directory of Open Access Journals (Sweden)

    José Ignacio Ruiz-Sanz

    2012-05-01

    Full Text Available Diverse plants of ethnobotanic interest in Amazonia are commonly used in traditional medicine. We determined the antioxidant potential against lipid peroxidation, the antimicrobial activity, and the polyphenol composition of several Amazonian plants (Brownea rosademonte, Piper glandulosissimum, Piper krukoffii, Piper putumayoense, Solanum grandiflorum, and Vismia baccifera. Extracts from the plant leaf, bark, and stem were prepared as aqueous infusions, as used in folk medicine, and added to rat liver microsomes exposed to iron. The polyphenolic composition was detected by reverse-phase HPLC coupled to diode-array detector and MS/MS analysis. The antimicrobial activity was tested by the spot-on-a-lawn method against several indicator microorganisms. All the extracts inhibited lipid oxidation, except the P. glandulosissimum stem. The plant extracts exhibiting high antioxidant potential (V. baccifera and B. rosademonte contained high levels of flavanols (particularly, catechin and epicatechin. By contrast, S. grandiflorum leaf, which exhibited very low antioxidant activity, was rich in hydroxycinnamic acids. None of the extracts showed antimicrobial activity. This study demonstrates for the first time the presence of bioactive polyphenolic compounds in several Amazonian plants, and highlights the importance of flavanols as major phenolic contributors to antioxidant activity.

  5. Open access to information bridges science and development in Amazonia: lessons of the SIAMAZONIA service

    International Nuclear Information System (INIS)

    Kalliola, Risto; Toivonen, Tuuli; Miyakawa, Victor; Mavila, Manuel

    2008-01-01

    Access to and availability of accurate information has often been stated to play an important role in sustainable environmental management. There is a growing trend of setting up internet-based information services to support the availability of relevant information. The current initiatives that aim to facilitate such information sharing through the web are still, however, often premature and unable to ensure constant flow of data from producers to users. We examine these common challenges by using as an example a network-based facility of biodiversity and environmental information about the Peruvian Amazon region called SIAMAZONIA. Launched in 2001, the service includes data provided by 13 different nodes. The experiences of this initiative have been both encouraging and confusing. A good professional level has been reached, but participation by large information holders is impeded. Participation is obviously considered an additional task rather than an attractive option for enhanced performance at the individual or institutional levels. This dilemma reflects a genuine problem in the modern scientific community, which still lacks agreed ways to reward those who share their data and results through the web. If these problems are solved, internet-based information sharing may become a vital resource for environmental management in Amazonia and also elsewhere

  6. Regional-scale drivers of forest structure and function in northwestern Amazonia.

    Directory of Open Access Journals (Sweden)

    Mark A Higgins

    Full Text Available Field studies in Amazonia have found a relationship at continental scales between soil fertility and broad trends in forest structure and function. Little is known at regional scales, however, about how discrete patterns in forest structure or functional attributes map onto underlying edaphic or geological patterns. We collected airborne LiDAR (Light Detection and Ranging data and VSWIR (Visible to Shortwave Infrared imaging spectroscopy measurements over 600 km2 of northwestern Amazonian lowland forests. We also established 83 inventories of plant species composition and soil properties, distributed between two widespread geological formations. Using these data, we mapped forest structure and canopy reflectance, and compared them to patterns in plant species composition, soils, and underlying geology. We found that variations in soils and species composition explained up to 70% of variation in canopy height, and corresponded to profound changes in forest vertical profiles. We further found that soils and plant species composition explained more than 90% of the variation in canopy reflectance as measured by imaging spectroscopy, indicating edaphic and compositional control of canopy chemical properties. We last found that soils explained between 30% and 70% of the variation in gap frequency in these forests, depending on the height threshold used to define gaps. Our findings indicate that a relatively small number of edaphic and compositional variables, corresponding to underlying geology, may be responsible for variations in canopy structure and chemistry over large expanses of Amazonian forest.

  7. Urban Forest and Rural Cities: Multi-sited Households, Consumption Patterns, and Forest Resources in Amazonia

    Directory of Open Access Journals (Sweden)

    Christine Padoch

    2008-12-01

    Full Text Available In much of the Amazon Basin, approximately 70% of the population lives in urban areas and urbanward migration continues. Based on data collected over more than a decade in two long-settled regions of Amazonia, we find that rural-urban migration in the region is an extended and complex process. Like recent rural-urban migrants worldwide, Amazonian migrants, although they may be counted as urban residents, are often not absent from rural areas but remain members of multi-sited households and continue to participate in rural-urban networks and in rural land-use decisions. Our research indicates that, despite their general poverty, these migrants have affected urban markets for both food and construction materials. We present two cases: that of açaí palm fruit in the estuary of the Amazon and of cheap construction timbers in the Peruvian Amazon. We find that many new Amazonian rural-urban migrants have maintained some important rural patterns of both consumption and knowledge. Through their consumer behavior, they are affecting the areal extent of forests; in the two floodplain regions discussed, tree cover is increasing. We also find changes in forest composition, reflecting the persistence of rural consumption patterns in cities resulting in increased demand for and production of açaí and cheap timber species.

  8. Chemical characterization of ancient pottery from the southwest Amazonia using neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Patricia R.; Munita, Casimiro S.; Neves, Eduardo G.; Zimpel, Carlos A., E-mail: camunita@ipen.br, E-mail: edgneves@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Universidade de Sao Paulo (MAE/USP), SP (Brazil). Museu de Arqueologia e Etnologia

    2017-11-01

    The analyzes carried out in this work aims to contribute to the discussion about the ceramic objects founded in Monte Castelo's sambaqui located at Southwest Amazonia. The first study accomplished by Miller in 1980 suggests that this archaeological site is inserted in the old contexts of production of ceramics in the Amazon. Until today, there are not any physical and chemical analysis studies in this ceramics and this kind of studies may help archaeological studies performed at the sambaqui. With this purpose, this work presents a preliminary study of chemical characterization of eighty-seven ceramic samples using the Neutron Activation Analysis (NAA). The analyzed elements were: As, K, La, Lu, Na, Nd, Sm, U, Yb, Ce, Co, Cr, Cs, Eu, Fe, Hf, Rb, Sc, Ta, Tb, Th. With the purpose to study the similarity/dissimilarity between the samples cluster and discriminant analysis were used. The results showed the existence of three different chemical groups that are in agreement with the archaeological studies made by Miller which found a sequence of cultural development, with three main occupational components whose dating ranging from 8.400 to 4.000 b.P. In this way, the results of this work are in agreement with miller's studies and suggest Bacabal's phase as the oldest ceramist culture in the Southwest of the Amazon. (author)

  9. Open access to information bridges science and development in Amazonia: lessons of the SIAMAZONIA service

    Energy Technology Data Exchange (ETDEWEB)

    Kalliola, Risto [Department of Geography, University of Turku, FI-20014 Turku (Finland); Toivonen, Tuuli [Department of Geography, University of Helsinki, FI-00014 Helsinki (Finland); Miyakawa, Victor; Mavila, Manuel [Instituto de Investigaciones de la AmazonIa Peruana, Apartado Postal 784, Iquitos (Peru)

    2008-07-15

    Access to and availability of accurate information has often been stated to play an important role in sustainable environmental management. There is a growing trend of setting up internet-based information services to support the availability of relevant information. The current initiatives that aim to facilitate such information sharing through the web are still, however, often premature and unable to ensure constant flow of data from producers to users. We examine these common challenges by using as an example a network-based facility of biodiversity and environmental information about the Peruvian Amazon region called SIAMAZONIA. Launched in 2001, the service includes data provided by 13 different nodes. The experiences of this initiative have been both encouraging and confusing. A good professional level has been reached, but participation by large information holders is impeded. Participation is obviously considered an additional task rather than an attractive option for enhanced performance at the individual or institutional levels. This dilemma reflects a genuine problem in the modern scientific community, which still lacks agreed ways to reward those who share their data and results through the web. If these problems are solved, internet-based information sharing may become a vital resource for environmental management in Amazonia and also elsewhere.

  10. Juvenile tree growth correlates with photosynthesis and leaf phosphorus content in central Amazonia

    Directory of Open Access Journals (Sweden)

    Ricardo Antonio Marenco

    2015-04-01

    Full Text Available Light and soil water availability may limit carbon uptake of trees in tropical rainforests. The objective of this work was to determine how photosynthetic traits of juvenile trees respond to variations in rainfall seasonality, leaf nutrient content, and opening of the forest canopy. The correlation between leaf nutrient content and annual growth rate of saplings was also assessed. In a terra firme rainforest of the central Amazon, leaf nutrient content and gas exchange parameters were measured in five sapling tree species in the dry and rainy season of 2008. Sapling growth was measured in 2008 and 2009. Rainfall seasonality led to variations in soil water content, but it did not affect leaf gas exchange parameters. Subtle changes in the canopy opening affected CO2 saturated photosynthesis (A pot, p = 0.04. Although A pot was affected by leaf nutrient content (as follows: P > Mg > Ca > N > K, the relative growth rate of saplings correlated solely with leaf P content (r = 0.52, p = 0.003. At present, reduction in soil water content during the dry season does not seem to be strong enough to cause any effect on photosynthesis of saplings in central Amazonia. This study shows that leaf P content is positively correlated with sapling growth in the central Amazon. Therefore, the positive effect of atmospheric CO2 fertilization on long-term tree growth will depend on the ability of trees to absorb additional amount of P

  11. Terrestrial mammal assemblages in protected and human impacted areas in Northern Brazilian Amazonia

    Directory of Open Access Journals (Sweden)

    Rodolfo Burgos de Luna

    2017-10-01

    Full Text Available Mammal communities in the vicinity of human settlements are often subject to subsistence hunting and retaliatory killings. We used fourteen digital camera traps equipped with infrared triggers to sample the medium-sized and large mammal communities for ca. 34 (±1.64 days per site. Diversity was measured as both Shannon entropy and Fager´s number of moves (NMS, and dominance was quantified using the Berger-Parker index. We used Kruskall-Wallis tests to investigate if there were statistically significant differences in richness, diversity and dominance among the sites. At an overall sampling effort of 1,946 trap days we recorded 216 independent observations of a total of 20 species belonging to 17 genera and 15 families. Richness and diversity appeared to be determined by forest structure, since, independent of the level of human impact, the richest areas were those closest to the ombrophilous forests of southern Guyana shield, closest to central Amazonia, whereas the poorest were at those sites closest to the vegetation mosaics of central Guyana shield. The disappearance of Tayassu pecari from the impacted areas as well as higher relative abundances in the protected areas, albeit not significant, foresees a possible bleak future for the mammalian assemblages in the near future.

  12. The inclusion of electric power and the challenge of sustainability in remote inland areas of the Amazon; A inclusao eletrica e o desafio da sustentabilidade nas areas remotas do interior da Amazonia

    Energy Technology Data Exchange (ETDEWEB)

    Cavalcante, Andreia Santos; Cartaxo, Elizabeth Ferreira [Universidade Federal do Amazonas (NIEMA/UFAM), Manaus, AM (Brazil). Nucleo Interdisciplinar de Energia, Meio Ambiente e Agua

    2008-07-01

    This article brings some reflections on the National Program of Universalization of the Access and Use of the Electric Energy, Luz para Todos, in areas as the Amazonia. This Program when implanting and executing the actions characterized the Brazilian state in way uniform, disrespecting the particularity and diversity of the Amazon region. This attitude has not met of the goals foreseen for the electrification of the Amazonian, evidencing thus, that the geographic, cultural and social multiplicities of climates and characteristics constitute great obstacles for the implantation of homogeneous politics. This, for certain, demonstrates that the potential of development of each region has differentiated dynamic, which would have to influence and to direct the formularization of politics. It characterizes this proposal bold and ambitious of the Federal Government from carried through empirical experience in an Amazonian community, Terra Preta do Limao, located in the city of Barreirinha. In this way, given referring to the organizational structure, the situation of job and income, to the access the social goods and services and the productive occupational vocation of this population bring answers on the impacts of the program in the improvement of the quality of life of this social segment. Moreover, it presents indications of that the resources destined to the implantation of the program, make impracticable, for its high cost, other social priorities. Although the electric energy is essential for the economic progress of a country, the expansion of its services to the necessary society to be seen in accord with sustainable criteria, of form to prevent the exploration and high consumption of the natural resources and the wastefulness of energy. With this reading, the work if considers to show to the incoherencies of the Program in the State of Amazon, evidencing the obstacles for the reach of the goals traced for the State. Therefore, considering what the Amazonia

  13. A new diminutive frog species of Adelophryne (Amphibia: Anura: Eleutherodactylidae) from the Atlantic Forest, southeastern Brazil.

    Science.gov (United States)

    Lourenço-de-Moraes, Ricardo; Ferreira, Rodrigo Barbosa; Fouquet, Antoine; Bastos, Rogério Pereira

    2014-08-04

    The genus Adelophryne is composed of diminutive frogs occurring in northern Amazonia and the Atlantic Forest. Herein we describe a new species of Adelophryne found in the leaf litter of primary and secondary forests in the mountainous region of Espírito Santo state, southeastern Brazil. The new species is characterized by its small body size, two phalanges in the finger IV, and a glandular ridge line that runs from the posterior part of eye to the insertion of the forelimb. This species is sensitive to edge effect and conversion of native forest into coffee and Eucalyptus plantations and may be listed as Endangered (EN) under B1ab(iii) criteria of the IUCN Red List.

  14. Diametric growth and time of passage of Minquartia guianensis after logging at Tapajós National Forest, Brazil

    Directory of Open Access Journals (Sweden)

    Cinthia Grazielle Carvalho Andrade

    2017-09-01

    Full Text Available Minquartia guianensis Aubl. (acariquara occurs at Acre, Amazonas, Roraima, Pará and Amapá states, with a great market demand and utility in the Amazon region. It is used mainly in civil construction due to its high durability and singular beauty, because of reentrances in its trunk, resulting in high market value. Most of used trees present small diameters, what is a critical factor for their management and commercialization. Thus, the objective of this study was to evaluate M. guianensis diametric growth and cutting cycle through the analysis of time of passage among diameter classes, 31 years after logging, at Tapajós National Forest, Pará State, Brazil. Five treatments were established and in each one 12 permanent sample plots of 0.25 ha were installed. All trees with diameter at 1.3 m above ground level (DBH ≥ 5 cm were measured from 1981 to 2012. Trees with DBH ≤ 50 cm have potential to be managed, due to the growth stagnation presented in larger diameter classes. These results may support silvicultural decisions to sustainable management.

  15. Ecological adaptation of wild peach palm, its in situ conservation and deforestation-mediated extinction in southern Brazilian Amazonia.

    Directory of Open Access Journals (Sweden)

    Charles R Clement

    Full Text Available BACKGROUND: The Arc of Fire across southern Amazonia seasonally attracts worldwide attention as forests are cut and burned for agricultural expansion. These forests contain numerous wild relatives of native South American crops, such as peach palm. METHODOLOGY/PRINCIPAL FINDINGS: Our prospecting expeditions examined critical areas for wild peach palm in the Arc of Fire in Mato Grosso, Pará, Maranhão and Tocantins, as well as areas not previously examined in Amazonas and Amapá states. Recent digitization of the RADAM Brasil project permitted comparison among RADAM's parataxonomists' observations, previous botanical collections and our prospecting. Mapping on soils and vegetation types enabled us to hypothesize a set of ecological preferences. Wild peach palm is best adapted to Ultisols (Acrisols in open forests across the Arc of Fire and westward into the more humid western Amazonia. Populations are generally small (fewer than 10 plants on slopes above watercourses. In northern Mato Grosso and southern Pará soybean fields and pastures now occupy numerous areas where RADAM identified wild peach palm. The controversial BR-163 Highway is already eroding wild peach palm as deforestation expands. CONCLUSIONS/SIGNIFICANCE: Many of these populations are now isolated by increasing forest fragmentation, which will lead to decreased reproduction via inbreeding depression and eventual extinction even without complete deforestation. Federal conservation areas are less numerous in the Arc of Fire than in other parts of Brazilian Amazonia, although there are indigenous lands; these conservation areas contain viable populations of wild peach palm and require better protection than they are currently receiving. Ex situ conservation of these populations is not viable given the relative lack of importance of domesticated peach palm and the difficulty of maintaining even economically interesting genetic resources.

  16. Prediction of rainfall anomalies during the dry to wet transition season over the Southern Amazonia using machine learning tools

    Science.gov (United States)

    Shan, X.; Zhang, K.; Zhuang, Y.; Fu, R.; Hong, Y.

    2017-12-01

    Seasonal prediction of rainfall during the dry-to-wet transition season in austral spring (September-November) over southern Amazonia is central for improving planting crops and fire mitigation in that region. Previous studies have identified the key large-scale atmospheric dynamic and thermodynamics pre-conditions during the dry season (June-August) that influence the rainfall anomalies during the dry to wet transition season over Southern Amazonia. Based on these key pre-conditions during dry season, we have evaluated several statistical models and developed a Neural Network based statistical prediction system to predict rainfall during the dry to wet transition for Southern Amazonia (5-15°S, 50-70°W). Multivariate Empirical Orthogonal Function (EOF) Analysis is applied to the following four fields during JJA from the ECMWF Reanalysis (ERA-Interim) spanning from year 1979 to 2015: geopotential height at 200 hPa, surface relative humidity, convective inhibition energy (CIN) index and convective available potential energy (CAPE), to filter out noise and highlight the most coherent spatial and temporal variations. The first 10 EOF modes are retained for inputs to the statistical models, accounting for at least 70% of the total variance in the predictor fields. We have tested several linear and non-linear statistical methods. While the regularized Ridge Regression and Lasso Regression can generally capture the spatial pattern and magnitude of rainfall anomalies, we found that that Neural Network performs best with an accuracy greater than 80%, as expected from the non-linear dependence of the rainfall on the large-scale atmospheric thermodynamic conditions and circulation. Further tests of various prediction skill metrics and hindcasts also suggest this Neural Network prediction approach can significantly improve seasonal prediction skill than the dynamic predictions and regression based statistical predictions. Thus, this statistical prediction system could have

  17. Ecological adaptation of wild peach palm, its in situ conservation and deforestation-mediated extinction in southern Brazilian Amazonia.

    Science.gov (United States)

    Clement, Charles R; Santos, Ronaldo P; Desmouliere, Sylvain J M; Ferreira, Evandro J L; Neto, João Tomé Farias

    2009-01-01

    The Arc of Fire across southern Amazonia seasonally attracts worldwide attention as forests are cut and burned for agricultural expansion. These forests contain numerous wild relatives of native South American crops, such as peach palm. Our prospecting expeditions examined critical areas for wild peach palm in the Arc of Fire in Mato Grosso, Pará, Maranhão and Tocantins, as well as areas not previously examined in Amazonas and Amapá states. Recent digitization of the RADAM Brasil project permitted comparison among RADAM's parataxonomists' observations, previous botanical collections and our prospecting. Mapping on soils and vegetation types enabled us to hypothesize a set of ecological preferences. Wild peach palm is best adapted to Ultisols (Acrisols) in open forests across the Arc of Fire and westward into the more humid western Amazonia. Populations are generally small (fewer than 10 plants) on slopes above watercourses. In northern Mato Grosso and southern Pará soybean fields and pastures now occupy numerous areas where RADAM identified wild peach palm. The controversial BR-163 Highway is already eroding wild peach palm as deforestation expands. Many of these populations are now isolated by increasing forest fragmentation, which will lead to decreased reproduction via inbreeding depression and eventual extinction even without complete deforestation. Federal conservation areas are less numerous in the Arc of Fire than in other parts of Brazilian Amazonia, although there are indigenous lands; these conservation areas contain viable populations of wild peach palm and require better protection than they are currently receiving. Ex situ conservation of these populations is not viable given the relative lack of importance of domesticated peach palm and the difficulty of maintaining even economically interesting genetic resources.

  18. Application of the Forhyd model to simulate net precipitation and intercepted water evaporation in forest canopies in Colombian amazonia

    International Nuclear Information System (INIS)

    Tellez Guio, Patricia; Boschell Villamarin, Francisco; Tobon Marin, Conrado

    2005-01-01

    Hydrologic simulation is a technique, which allows us to understand the relationships among hydrological, biological and ecological variables in an ecosystem. In this research, the FORHYD model is used to simulate the net precipitation and the water intercepted by the canopies of a mature forest, a 30-year old secondary forest, an 18-year old secondary forest, a 5-year old secondary forest, and a shifting cultivation plot, all located in Colombia's amazonia. The model calculates the water budget of the canopy by using the precipitation rates, canopy drainage and evaporation of the water intercepted by the canopy. This paper is the second one in a series of papers reporting the results of the research on the simulation of the hydrological fluxes in three different land use types of Colombian amazonia. The research was carried out in middle Caqueta of Colombian amazonia (northwest amazon basin). The FORHYD model was calibrated and validated by using field observations of the climate, net precipitation (PT), thoughtful (TH) and stem flow (ST), which were monitored during a period of 15 months from March 2001 to June 2002. These observations were used as both input variables and diagnostic variables to probe the model's precision to simulate field observations. Results showed that FORHYD simulates with a good precision the net precipitation and the evaporation of the water intercepted by the canopy. However, the model's precision depends on a good parameterization, which in turn depends on a good database of field observations. The model is a good tool for simulating the hydrological cycle and can be used to simulate critical scenarios of climate variability

  19. Preservación ambiental de la amazonia colombiana: retos para la política fiscal

    OpenAIRE

    Francisco Azuero; Jorge Armando Rodríguez

    2016-01-01

    Este artículo explora los retos encarados por la política fiscal en la preservación de la Amazonia colombiana. Se discuten algunos sesgos en contra del gasto público ambiental y se examinan las modalidades de financiación de la función estatal de protección del ambiente en la región. Los autores arguyen que muchas de las herramientas fiscales empleadas en Colombia para el efecto generan incentivos contrarios a los objetivos de conservación. Además de que las externalidades ambientales rebasan...

  20. Ocurrencia de hongos formadores de micorriza arbuscular asociados a ají (Capsicum sp.) en la Amazonia colombiana

    OpenAIRE

    Cardona, Gladys; Peña-Venegas, Clara Patricia; arcos, Adriana

    2008-01-01

    Capsicum sp. es una especie nativa de América de gran importancia por su diversidad de usos. La Amazonia colombiana es considerada uno de los centros de origen y alberga una gran riqueza de morfoespecies. A pesar de su importancia para el crecimiento y supervivencia de plantas bajo condiciones limitantes de nutrientes, son escasos los trabajos relacionados con la dinámica de los hongos formadores de micorriza arbuscular (HFMA) en Capsicum. Se estudió la ocurrencia de HFMA, a partir de colecta...

  1. Synergistic impacts of deforestation, climate change and fire on the future biomes distribution in Amazonia

    Science.gov (United States)

    Sampaio, G.; Cardoso, M. F.; Nobre, C. A.; Salazar, L. F.

    2013-05-01

    Several studies indicate future increase of environmental risks for the ecosystems in the Amazon region as a result of climate and land-use change, and their synergistic interactions. Modeling studies (e.g. Oyama and Nobre 2004, Salazar et al. 2007, Malhi et al. 2008) project rapid and irreversible replacement of forests by savannas with large-scale losses of biodiversity and livelihoods for people in the region. This process is referred to as the Amazon Dieback, where accelerated plant mortality due to environmental changes lead to forest collapse and savannas expansion after "tipping points" in climate and land surface changes are achieved. In this study we performed new analyses to quantify how deforestation, climate change and fire may combine to affect the distribution of major biomes in Amazonia. Changes in land use consider deforestation scenarios of 0%, 20%, 40%, and 50% (Sampaio et al., 2007), with and without fires (Cardoso et al., 2008), under the two greenhouse gases scenarios B1 and A2 and three "representative concentration pathways" (RCPs): 2.6, 4.5 and 8.5, for years 2015-2034 and 2040-2059 ("2025" and "2050" time-slices), from IPCC AR4 and CMIP5. The results show that the area affected in scenarios A2 and RCP 8.5 is larger than in the climate scenario B1 and RCP 2.6, and in both cases the effect is progressively higher in time. Most important changes occur in the East and South of the Amazon, with replacement of tropical forest by seasonal forest and savanna. The effect of fire in this region is important in all scenarios. The Northwest Amazon presents the smallest changes in the area of tropical forest, indicating that even for substantial land-use modifications and global climate change, the resulting atmospheric conditions would still support tropical forest in the region. In summary, we conclude that the synergistic combination of deforestation, climate change resulting from global warming, and the potential for higher fire occurrence may lead

  2. Impacts of Amazonia biomass burning aerosols assessed from short-range weather forecasts

    Directory of Open Access Journals (Sweden)

    S. R. Kolusu

    2015-11-01

    Full Text Available The direct radiative impacts of biomass burning aerosols (BBA on meteorology are investigated using short-range forecasts from the Met Office Unified Model (MetUM over South America during the South American Biomass Burning Analysis (SAMBBA. The impacts are evaluated using a set of three simulations: (i no aerosols, (ii with monthly mean aerosol climatologies and (iii with prognostic aerosols modelled using the Coupled Large-scale Aerosol Simulator for Studies In Climate (CLASSIC scheme. Comparison with observations show that the prognostic CLASSIC scheme provides the best representation of BBA. The impacts of BBA are quantified over central and southern Amazonia from the first and second day of 2-day forecasts during 14 September–3 October 2012. On average, during the first day of the forecast, including prognostic BBA reduces the clear-sky net radiation at the surface by 15 ± 1 W m−2 and reduces net top-of-atmosphere (TOA radiation by 8 ± 1 W m−2, with a direct atmospheric warming of 7 ± 1 W m−2. BBA-induced reductions in all-sky radiation are smaller in magnitude: 9.0 ± 1 W m−2 at the surface and 4.0 ± 1 W m−2 at TOA. In this modelling study the BBA therefore exert an overall cooling influence on the Earth–atmosphere system, although some levels of the atmosphere are directly warmed by the absorption of solar radiation. Due to the reduction of net radiative flux at the surface, the mean 2 m air temperature is reduced by around 0.1 ± 0.02 °C. The BBA also cools the boundary layer (BL but warms air above by around 0.2 °C due to the absorption of shortwave radiation. The overall impact is to reduce the BL depth by around 19 ± 8 m. These differences in heating lead to a more anticyclonic circulation at 700 hPa, with winds changing by around 0.6 m s−1. Inclusion of climatological or prognostic BBA in the MetUM makes a small but significant improvement in forecasts of temperature and relative humidity, but improvements were

  3. Dark Earths and manioc cultivation in Central Amazonia: a window on pre-Columbian agricultural systems?

    Directory of Open Access Journals (Sweden)

    James A. Fraser

    Full Text Available Many commentators highlight the fertility of Anthropogenic Dark Earths (ADE, emphasizing their potential for sustainable agriculture. Some scholars believe that terra mulata (the less fertile, more extensive form of ADE was created by means of agricultural practices used by large settled populations of pre-Columbian farmers. But what was it that these Amerindian farmers were growing? Until recently, scholarly consensus held that manioc does not perform well on ADE. New research on the middle Madeira River is showing, however, that this consensus was premature. In this region, the most common crop in ADE fields is bitter manioc. Farmers there have various landraces of manioc that they believe yield particularly well on ADE, and logically plant more of these varieties on ADE. Aspects of the behaviour and perception of manioc cultivation among 52 farmers at the community of Barro Alto were measured quantitatively on four terra firme soil types (Terra Preta, Terra Mulata, Oxisols and Ultisols. These farmers plant different configurations of landraces in different soils, according to their perception of the suitability of particular landraces and their characteristics to certain soil types and successional processes. This, in turn, shapes selective pressures on these varieties, as new genetic material incorporated from volunteer seedlings is more likely to contain traits present in the most prevalent landrace(s in each soil type. Owing to localized population pressure at Barro Alto, manioc is under more intensive cultivation systems, with shorter cropping periods (5-10 months and shorter fallow periods (1-2 years. The outcome of these processes is different co-evolutionary dynamics on ADE as opposed to non-anthropogenic soils. Further anthropological study of manioc swiddening in one of the richest agricultural environments in Amazonia can fill a gap in the literature, thus opening an additional window on the pre-Columbian period.

  4. Dark Earths and manioc cultivation in Central Amazonia: a window on pre-Columbian agricultural systems?

    Directory of Open Access Journals (Sweden)

    James A. Fraser

    2008-08-01

    Full Text Available Many commentators highlight the fertility of Anthropogenic Dark Earths (ADE, emphasizing their potential for sustainable agriculture. Some scholars believe that terra mulata (the less fertile, more extensive form of ADE was created by means of agricultural practices used by large settled populations of pre-Columbian farmers. But what was it that these Amerindian farmers were growing? Until recently, scholarly consensus held that manioc does not perform well on ADE. New research on the middle Madeira River is showing, however, that this consensus was premature. In this region, the most common crop in ADE fields is bitter manioc. Farmers there have various landraces of manioc that they believe yield particularly well on ADE, and logically plant more of these varieties on ADE. Aspects of the behaviour and perception of manioc cultivation among 52 farmers at the community of Barro Alto were measured quantitatively on four terra firme soil types (Terra Preta, Terra Mulata, Oxisols and Ultisols. These farmers plant different configurations of landraces in different soils, according to their perception of the suitability of particular landraces and their characteristics to certain soil types and successional processes.This, in turn, shapes selective pressures on these varieties, as new genetic material incorporated from volunteer seedlings is more likely to contain traits present in the most prevalent landrace(s in each soil type. Owing to localized population pressure at Barro Alto, manioc is under more intensive cultivation systems, with shorter cropping periods (5-10 months and shorter fallow periods (1-2 years. The outcome of these processes is different co-evolutionary dynamics on ADE as opposed to non-anthropogenic soils. Further anthropological study of manioc swiddening in one of the richest agricultural environments in Amazonia can fill a gap in the literature, thus opening an additional window on the pre-Columbian period.

  5. Geochemical characterization of the largest upland lake of the Brazilian Amazonia: Impact of provenance and processes

    Science.gov (United States)

    Sahoo, Prafulla Kumar; Guimarães, José Tasso Felix; Souza-Filho, Pedro Walfir Martins; da Silva, Marcio Sousa; Nascimento, Wilson, Júnior; Powell, Mike A.; Reis, Luiza Santos; Pessenda, Luiz Carlos Ruiz; Rodrigues, Tarcísio Magevski; da Silva, Delmo Fonseca; Costa, Vladimir Eliodoro

    2017-12-01

    Lake Três Irmãs (LTI), the largest upland lake in the Brazilian Amazonia, located in Serra dos Carajás, was characterized using multi-elemental and isotope geochemistry (δ13C and δ15N) to understand the significance of organic and inorganic sources, weathering and sedimentary processes on the distribution of elements in lake bottom (surficial) sediments. Carbon and nitrogen isotopes from sedimentary organic matter suggest C3 terrestrial plants (forests > canga vegetation), macrophytes and freshwater DOC as the main sources. Sediments are depleted in most of the major oxides (except Fe2O3 and P2O5) when compared to upper continental crust (UCC) and their spatial distribution is highly influenced by catchment lithology. Principal Component Analysis revealed that most of the trace elements (Ba, Sr, Rb, Sc, Th, U, Zr, Hf, Nb, Y, V, Cr, Ga, Co, Ni) and REEs are closely correlated with Al and Ti (PC1; Group-1), so their redistribution is less influenced by post-depositional process. This is due to their relative immobility and being hosted by Al-bearing minerals during laterization. High Chemical Index of Alteration (CIA), Mafic Index of Alteration (MIA) and Index of Laterization (IOL) values indicate intense chemical weathering at source areas, but the weathering transformation was better quantified by IOL. A-CN-K plot along with elemental ratios (Al/K, Ti/K, Ti/Zr, La/Al, Cr/Th, Co/Th, La/Sm, La/Gd, Zr/Y, and Eu/Eu*) as well as chondrite-normalized REE patterns show that the detritic sediments are mainly sourced from ferruginous laterites and soils in the catchment, which may have characteristics similar to mafic rocks.

  6. Global warming and climate change in Amazonia: Climate-vegetation feedback and impacts on water resources

    Science.gov (United States)

    Marengo, José; Nobre, Carlos A.; Betts, Richard A.; Cox, Peter M.; Sampaio, Gilvan; Salazar, Luis

    This chapter constitutes an updated review of long-term climate variability and change in the Amazon region, based on observational data spanning more than 50 years of records and on climate-change modeling studies. We start with the early experiments on Amazon deforestation in the late 1970s, and the evolution of these experiments to the latest studies on greenhouse gases emission scenarios and land use changes until the end of the twenty-first century. The "Amazon dieback" simulated by the HadCM3 model occurs after a "tipping point" of CO2 concentration and warming. Experiments on Amazon deforestation and change of climate suggest that once a critical deforestation threshold (or tipping point) of 40-50% forest loss is reached in eastern Amazonia, climate would change in a way which is dangerous for the remaining forest. This may favor a collapse of the tropical forest, with a substitution of the forest by savanna-type vegetation. The concept of "dangerous climate change," as a climate change, which induces positive feedback, which accelerate the change, is strongly linked to the occurrence of tipping points, and it can be explained as the presence of feedback between climate change and the carbon cycle, particularly involving a weakening of the current terrestrial carbon sink and a possible reversal from a sink (as in present climate) to a source by the year 2050. We must, therefore, currently consider the drying simulated by the Hadley Centre model(s) as having a finite probability under global warming, with a potentially enormous impact, but with some degree of uncertainty.

  7. DISTRIBUTION OF ORGANIC CARBON IN DIFFERENT SOIL FRACTIONS IN ECOSYSTEMS OF CENTRAL AMAZONIA

    Directory of Open Access Journals (Sweden)

    Jean Dalmo de Oliveira Marques

    2015-02-01

    Full Text Available Organic matter plays an important role in many soil properties, and for that reason it is necessary to identify management systems which maintain or increase its concentrations. The aim of the present study was to determine the quality and quantity of organic C in different compartments of the soil fraction in different Amazonian ecosystems. The soil organic matter (FSOM was fractionated and soil C stocks were estimated in primary forest (PF, pasture (P, secondary succession (SS and an agroforestry system (AFS. Samples were collected at the depths 0-5, 5-10, 10-20, 20-40, 40-60, 60-80, 80-100, 100-160, and 160-200 cm. Densimetric and particle size analysis methods were used for FSOM, obtaining the following fractions: FLF (free light fraction, IALF (intra-aggregate light fraction, F-sand (sand fraction, F-clay (clay fraction and F-silt (silt fraction. The 0-5 cm layer contains 60 % of soil C, which is associated with the FLF. The F-clay was responsible for 70 % of C retained in the 0-200 cm depth. There was a 12.7 g kg-1 C gain in the FLF from PF to SS, and a 4.4 g kg-1 C gain from PF to AFS, showing that SS and AFS areas recover soil organic C, constituting feasible C-recovery alternatives for degraded and intensively farmed soils in Amazonia. The greatest total stocks of carbon in soil fractions were, in decreasing order: (101.3 Mg ha-1 of C - AFS > (98.4 Mg ha-1 of C - FP > (92.9 Mg ha-1 of C - SS > (64.0 Mg ha-1 of C - P. The forms of land use in the Amazon influence C distribution in soil fractions, resulting in short- or long-term changes.

  8. Increased Wildfire Risk Driven by Climate and Development Interactions in the Bolivian Chiquitania, Southern Amazonia.

    Science.gov (United States)

    Devisscher, Tahia; Anderson, Liana O; Aragão, Luiz E O C; Galván, Luis; Malhi, Yadvinder

    2016-01-01

    Wildfires are becoming increasingly dominant in tropical landscapes due to reinforcing feedbacks between land cover change and more severe dry conditions. This study focused on the Bolivian Chiquitania, a region located at the southern edge of Amazonia. The extensive, unique and well-conserved tropical dry forest in this region is susceptible to wildfires due to a marked seasonality. We used a novel approach to assess fire risk at the regional level driven by different development trajectories interacting with changing climatic conditions. Possible future risk scenarios were simulated using maximum entropy modelling with presence-only data, combining land cover, anthropogenic and climatic variables. We found that important determinants of fire risk in the region are distance to roads, recent deforestation and density of human settlements. Severely dry conditions alone increased the area of high fire risk by 69%, affecting all categories of land use and land cover. Interactions between extreme dry conditions and rapid frontier expansion further increased fire risk, resulting in potential biomass loss of 2.44±0.8 Tg in high risk area, about 1.8 times higher than the estimates for the 2010 drought. These interactions showed particularly high fire risk in land used for 'extensive cattle ranching', 'agro-silvopastoral use' and 'intensive cattle ranching and agriculture'. These findings have serious implications for subsistence activities and the economy in the Chiquitania, which greatly depend on the forestry, agriculture and livestock sectors. Results are particularly concerning if considering the current development policies promoting frontier expansion. Departmental protected areas inhibited wildfires when strategically established in areas of high risk, even under drought conditions. However, further research is needed to assess their effectiveness accounting for more specific contextual factors. This novel and simple modelling approach can inform fire and land

  9. Increased Wildfire Risk Driven by Climate and Development Interactions in the Bolivian Chiquitania, Southern Amazonia.

    Directory of Open Access Journals (Sweden)

    Tahia Devisscher

    Full Text Available Wildfires are becoming increasingly dominant in tropical landscapes due to reinforcing feedbacks between land cover change and more severe dry conditions. This study focused on the Bolivian Chiquitania, a region located at the southern edge of Amazonia. The extensive, unique and well-conserved tropical dry forest in this region is susceptible to wildfires due to a marked seasonality. We used a novel approach to assess fire risk at the regional level driven by different development trajectories interacting with changing climatic conditions. Possible future risk scenarios were simulated using maximum entropy modelling with presence-only data, combining land cover, anthropogenic and climatic variables. We found that important determinants of fire risk in the region are distance to roads, recent deforestation and density of human settlements. Severely dry conditions alone increased the area of high fire risk by 69%, affecting all categories of land use and land cover. Interactions between extreme dry conditions and rapid frontier expansion further increased fire risk, resulting in potential biomass loss of 2.44±0.8 Tg in high risk area, about 1.8 times higher than the estimates for the 2010 drought. These interactions showed particularly high fire risk in land used for 'extensive cattle ranching', 'agro-silvopastoral use' and 'intensive cattle ranching and agriculture'. These findings have serious implications for subsistence activities and the economy in the Chiquitania, which greatly depend on the forestry, agriculture and livestock sectors. Results are particularly concerning if considering the current development policies promoting frontier expansion. Departmental protected areas inhibited wildfires when strategically established in areas of high risk, even under drought conditions. However, further research is needed to assess their effectiveness accounting for more specific contextual factors. This novel and simple modelling approach can

  10. The costs of evaluating species densities and composition of snakes to assess development impacts in amazonia.

    Directory of Open Access Journals (Sweden)

    Rafael de Fraga

    Full Text Available Studies leading to decision-making for environmental licensing often fail to provide accurate estimates of diversity. Measures of snake diversity are regularly obtained to assess development impacts in the rainforests of the Amazon Basin, but this taxonomic group may be subject to poor detection probabilities. Recently, the Brazilian government tried to standardize sampling designs by the implementation of a system (RAPELD to quantify biological diversity using spatially-standardized sampling units. Consistency in sampling design allows the detection probabilities to be compared among taxa, and sampling effort and associated cost to be evaluated. The cost effectiveness of detecting snakes has received no attention in Amazonia. Here we tested the effects of reducing sampling effort on estimates of species densities and assemblage composition. We identified snakes in seven plot systems, each standardised with 14 plots. The 250 m long centre line of each plot followed an altitudinal contour. Surveys were repeated four times in each plot and detection probabilities were estimated for the 41 species encountered. Reducing the number of observations, or the size of the sampling modules, caused significant loss of information on species densities and local patterns of variation in assemblage composition. We estimated the cost to find a snake as $ 120 U.S., but general linear models indicated the possibility of identifying differences in assemblage composition for half the overall survey costs. Decisions to reduce sampling effort depend on the importance of lost information to target-issues, and may not be the preferred option if there is the potential for identifying individual snake species requiring specific conservation actions. However, in most studies of human disturbance on species assemblages, it is likely to be more cost-effective to focus on other groups of organisms with higher detection probabilities.

  11. Las palmas entre los grupos cazadores-recolectores de la Amazonia Colombiana

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    Morcote Ríos Gaspar

    1998-06-01

    Full Text Available We compare past and present systems of management of palms in the Colombian Amazon, based on archaeological studies of preceramic groups in the middle Caquetá region and ethnographic research on the nomadic Nukak people, who inhabit northeastern Guaviare department. Astrocaryum aculeatum, Attalea maripe, Mauritia flexuosa, Oenocarpus bataua, Oenocarpus bacaba y Oenocarpus mapora, have been used from the early Holocene through the present time. Among these, Oenocarpus bataua has remained the most important food species. We conclude that one of the mananging strategies of the tropical rain forest is the simultaneous improvement of ecological units, especially in the tertiary sedimentary plains, and that such management probably has a long history in the region.Se presenta una comparación sobre el manejo de las palmas en la Amazonia Colombiana, basado en los resultados de un estudio arqueológico de grupos precerámicos en la región del Medio Caquetá y uno etnográfico del pueblo nómada Nukak que habita la zona nororiental del departamento del Guaviare. Se encontró que Astrocaryum aculeatum, A ttalea maripa, Mauritia flexuosa, Oenocarpus bataua, Oenocarpus bacaba y Oenocarpus mapora son algunas de las palmas usadas desde el Holoceno temprano hasta el presente. Entre estas Oenocarpus bataua es la especie más importante como fuente de alimento. Así mismo, se concluye que una de las estrategias de manejo en el bosque húmedo tropical es el aprovechamiento simultáneo de diferentes unidades ecológicas, con predominio del plano sedimentario terciario. Es probable que este tipo de manejo tenga en la región una larga historia.

  12. A 6900-year history of landscape modification by humans in lowland Amazonia

    Science.gov (United States)

    Bush, M. B.; Correa-Metrio, A.; McMichael, C. H.; Sully, S.; Shadik, C. R.; Valencia, B. G.; Guilderson, T.; Steinitz-Kannan, M.; Overpeck, J. T.

    2016-06-01

    A sedimentary record from the Peruvian Amazon provided evidence of climate and vegetation change for the last 6900 years. Piston cores collected from the center of Lake Sauce, a 20 m deep lake at 600 m elevation, were 19.7 m in length. The fossil pollen record showed a continuously forested catchment within the period of the record, although substantial changes in forest composition were apparent. Fossil charcoal, found throughout the record, was probably associated with humans setting fires. Two fires, at c. 6700 cal BP and 4270 cal BP, appear to have been stand-replacing events possibly associated with megadroughts. The fire event at 4270 cal BP followed a drought that caused lowered lake levels for several centuries. The successional trajectories of forest recovery following these large fires were prolonged by smaller fire events. Fossil pollen of Zea mays (cultivated maize) provided evidence of agricultural activity at the site since c. 6320 cal BP. About 5150 years ago, the lake deepened and started to deposit laminated sediments. Maize agriculture reached a peak of intensity between c. 3380 and 700 cal BP. Fossil diatom data provided a proxy for lake nutrient status and productivity, both of which peaked during the period of maize cultivation. A marked change in land use was evident after c. 700 cal BP when maize agriculture was apparently abandoned at this site. Iriartea, a hyperdominant of riparian settings in western Amazonia, increased in abundance within the last 1100 years, but declined markedly at c. 1070 cal BP and again between c. 80 and -10 cal BP.

  13. Environmental Factors and Ecosystems Associated with Canine Visceral Leishmaniasis in Northeastern Brazil.

    Science.gov (United States)

    da Costa, Andréa Pereira; Costa, Francisco Borges; Soares, Herbert Sousa; Ramirez, Diego Garcia; de Carvalho Araújo, Andreina; da Silva Ferreira, Juliana Isabel Giuli; Tonhosolo, Renata; Dias, Ricardo Augusto; Gennari, Solange Maria; Marcili, Arlei

    2015-12-01

    Environment influences the composition, distribution, and behavior of the vectors and mammalian hosts involved in the transmission of visceral leishmaniasis (VL), affecting the epidemiology of the disease. In Brazil, the urbanization process and canine cases of VL are indicators for local health authorities. This study aimed to investigate the occurrence of the canine visceral leishmaniasis (CVL) in Maranhão State, Brazil. Blood samples collected from 960 dogs from six municipalities and six different ecosystems (Baixada Maranhense, Mangue, Mata dos Cocais, Amazônia, Cerrado, and Restinga) to serological tests (enzyme-linked immunosorbent assay [ELISA], indirect fluorescence antibody test [IFAT], and chromatographic immunoassay methods [Dual Path Platform technology, DPP(®)]) and parasitological diagnosis. From serological tests, 11.14% (107) of the dogs were positive for CVL, with 59.16% (568), 14.5% (148), and 131% (126) positives to ELISA, DPP, and IFAT tests, respectively. Only seven animals (0.73%) were positive in a parasitological test. We also performed parasite isolation and phylogenetic characterization. All isolates of dogs obtained from Maranhão were grouped in a single branch with Leishmania infantum chagasi from Brazil. The ecosystem Amazonia presented the highest positivity rates to CVL in serological and parasitological tests. Brazilian biomes/ecosystems suffer large degradation and may favor, depending on climatic conditions, the installation of new diseases. In the case of VL, dogs are reservoirs of parasites and sentinels for human infection.

  14. Cross-Sectional Serological Survey of Human Fascioliasis in Canutama Municipality in Western Amazon, Brazil

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    Marcel Gonçalves Maciel

    2018-01-01

    Full Text Available Background. Fascioliasis is an important parasitic disease. In the northern region of Brazil, a human parasite infection has been reported through a coprological survey. Eggs of Fasciola hepatica were found in fecal samples of 11 individuals. Knowledge of the infection in animals or the presence of snails is necessary to address the possibility of the parasite cycle occurrence in that region. The aim of this study was to describe the transmission of human fascioliasis in Canutama, Amazonas, in Western Amazonia, Brazil. Methods. Serological (ELISA and Western Blot, WB and parasitological analyses were carried out in humans. In addition, the presence of the intermediate snail host within the community was examined. Results. A total of 434 human samples were included in the study, of which 36 (8.3% were reactive by ELISA and 8 (1.8% were reactive by WB. Fasciola hepatica eggs were found in one human sample. The occurrence of the intermediated host was recorded and 31/43 specimens were identified as Lymnaea columella. Conclusion. Canutama constitutes a focus of transmission of human fascioliasis. This study describes the first serological survey for human fascioliasis, as well as its simultaneous occurrence in human hosts and possible intermediates performed in northern Brazil.

  15. High genetic diversity among and within bitter manioc varieties cultivated in different soil types in Central Amazonia

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    Alessandro Alves-Pereira

    2017-04-01

    Full Text Available Abstract Although manioc is well adapted to nutrient-poor Oxisols of Amazonia, ethnobotanical observations show that bitter manioc is also frequently cultivated in the highly fertile soils of the floodplains and Amazonian dark earths (ADE along the middle Madeira River. Because different sets of varieties are grown in each soil type, and there are agronomic similarities between ADE and floodplain varieties, it was hypothesized that varieties grown in ADE and floodplain were more closely related to each other than either is to varieties grown in Oxisols. We tested this hypothesis evaluating the intra-varietal genetic diversity and the genetic relationships among manioc varieties commonly cultivated in Oxisols, ADE and floodplain soils. Genetic results did not agree with ethnobotanical expectation, since the relationships between varieties were variable and most individuals of varieties with the same vernacular name, but grown in ADE and floodplain, were distinct. Although the same vernacular name could not always be associated with genetic similarities, there is still a great amount of variation among the varieties. Many ecological and genetic processes may explain the high genetic diversity and differentiation found for bitter manioc varieties, but all contribute to the maintenance and amplification of genetic diversity within the manioc in Central Amazonia.

  16. Co-Evolution and Bio-Social Construction: The Kichwa Agroforestry Systems (Chakras in the Ecuadorian Amazonia

    Directory of Open Access Journals (Sweden)

    Daniel Coq-Huelva

    2017-10-01

    Full Text Available Polycultured agrarian systems in Ecuadorian Amazonia (also called chakras or swollen gardens are characterised by a market-oriented crop for the generation of monetary income, for example, cocoa, other agricultural products (e.g., banana and cassava, and livestock for family farm consumption. Moreover, a chakra is an outstanding example of agroforestry production, in which ecological, social and economic elements co-evolve from a set of close and strong connections. In this context, the conservation and transformation of their biological subsystems can be understood as the result of complex interactions between anthropogenic and non-anthropogenic factors. In turn, such interactions are essential to provide food and monetary income to the indigenous community. Relevant agency capabilities exist that could cause an agroforestry system to take a different path of co-evolution, that is, towards greater or lesser sustainability associated with different levels of complexity. In conclusion, chakras have key ecological features that can mitigate the impact of human population growth in Amazonia. Additionally, chakras have their own processes of social self-regulation which enhance the possibilities of adaptation of Kichwa communities to changing environmental conditions, being essential elements in local food sovereignty, equitable gender relations and the respect of ancestral wisdom.

  17. Variações anuais na produção de frutos e sementes de Castanheira-do-Brasil (Bertholletia excelsa Bonpl., Lecythidaceae em florestas nativas de Roraima

    Directory of Open Access Journals (Sweden)

    Helio Tonini

    2014-02-01

    Full Text Available Este trabalho foi desenvolvido com o objetivo de estudar as variações anuais na produção de frutos e sementes entre populações e indivíduos em castanhais nativos de Roraima. Os dados foram obtidos em cinco parcelas permanentes de 300 m x 300 m instaladas nos Municípios de Caracaraí e São João da Baliza. Nas parcelas permanentes, todas as castanheiras com diâmetro à altura do peito (DAP superior ou igual a 10 cm foram identificadas, medidas e numeradas através de placas de alumínio presas aos fustes por pregos. Durante o período de queda dos frutos (março a julho, as árvores foram visitadas em duas ocasiões no meio e no final desse período, e os frutos contados, abertos e pesados com balança de gancho digital com precisão de 50 g. A produção de frutos e sementes varia entre populações e indivíduos e a maioria não produz frutos todos os anos. No ano de maior produção, um castanhal chega a produzir 52 vezes mais do que em anos de baixa. Nos locais estudados, a produção total concentra-se em um pequeno número de indivíduos com um ano de pico de produção (mast-year.

  18. Sustainability with an Ethical Aim: Lessons from an American Nun in Amazonia

    Science.gov (United States)

    Demaree, Stephanie

    2012-01-01

    Research Topic: An exploration into human imagination, ethical aim and action are the progenitors for reconciliation between humans and their environment. This study of two successful projects in Brazil provides an example of working toward a balance between human endeavors and sustainable environments. This inquiry is an exploration that…

  19. Small-scale tourism development in Brazilian Amazonia: The creation of a ‘tourist bubble’

    NARCIS (Netherlands)

    Ros-Tonen, M.A.F.; Werneck, A.F.

    2009-01-01

    In Brazil, tourism is promoted as a means of generating employment, tax revenues, foreign exchange and investments in infrastructure. The Amazon region is thereby primarily marketed as a ‘green’ destination. One such a destination is the village of Alter do Chão in the municipality of Santarém in

  20. Anuran trypanosomes: phylogenetic evidence for new clades in Brazil.

    Science.gov (United States)

    da S Ferreira, Juliana I G; da Costa, Andrea P; Ramirez, Diego; Roldan, Jairo A M; Saraiva, Danilo; da S Founier, Gislene F R; Sue, Ana; Zambelli, Erick R; Minervino, Antonio H H; Verdade, Vanessa K; Gennari, Solange M; Marcili, Arlei

    2015-05-01

    Trypanosomes of anurans and fish are grouped into the Aquatic Clade which includes species isolated from fish, amphibians, turtles and platypus, usually transmitted by leeches and phlebotomine sand flies. Trypanosomes from Brazilian frogs are grouped within the Aquatic Clade with other anuran trypanosome species, where there seems to be coevolutionary patterns with vertebrate hosts and association to Brazilian biomes (Atlantic Forest, Pantanal and Amazonia Rainforest). We characterised the anuran trypanosomes from two different areas of the Cerrado biome and examined their phylogenetic relationships based on the SSU rRNA gene. A total of 112 anurans of six species was analysed and trypanosome prevalence evaluated through haemoculture was found to be 7% (8 positive frogs). However, only three isolates (2.7%) from two anuran species were recovered and cryopreserved. Analysis including SSU rDNA sequences from previous studies segregated the anuran trypanosomes into six groups, the previously reported An01 to An04, and An05 and An06 reported herein. Clade An05 comprises the isolates from Leptodactylus latrans (Steffen) and Pristimantis sp. captured in the Cerrado biome and Trypanosoma chattoni Mathis & Leger, 1911. The inclusion of new isolates in the phylogenetic analyses provided evidence for a new group (An06) of parasites from phlebotomine hosts. Our results indicate that the diversity of trypanosome species is underestimated since studies conducted in Brazil and other regions of the world are still few.

  1. A TRMM-Calibrated Infrared Rainfall Algorithm Applied Over Brazil

    Science.gov (United States)

    Negri, A. J.; Xu, L.; Adler, R. F.; Einaudi, Franco (Technical Monitor)

    2000-01-01

    The development of a satellite infrared technique for estimating convective and stratiform rainfall and its application in studying the diurnal variability of rainfall in Amazonia are presented. The Convective-Stratiform. Technique, calibrated by coincident, physically retrieved rain rates from the Tropical Rain Measuring Mission (TRMM) Microwave Imager (TMI), is applied during January to April 1999 over northern South America. The diurnal cycle of rainfall, as well as the division between convective and stratiform rainfall is presented. Results compare well (a one-hour lag) with the diurnal cycle derived from Tropical Ocean-Global Atmosphere (TOGA) radar-estimated rainfall in Rondonia. The satellite estimates reveal that the convective rain constitutes, in the mean, 24% of the rain area while accounting for 67% of the rain volume. The effects of geography (rivers, lakes, coasts) and topography on the diurnal cycle of convection are examined. In particular, the Amazon River, downstream of Manaus, is shown to both enhance early morning rainfall and inhibit afternoon convection. Monthly estimates from this technique, dubbed CST/TMI, are verified over a dense rain gage network in the state of Ceara, in northeast Brazil. The CST/TMI showed a high bias equal to +33% of the gage mean, indicating that possibly the TMI estimates alone are also high. The root mean square difference (after removal of the bias) equaled 36.6% of the gage mean. The correlation coefficient was 0.77 based on 72 station-months.

  2. Dendrometria de espécies nativas em plantios homogêneos no estado de Roraima: andiroba (Carapa guianensis Aubl, castanha-do-Brasil (Bertholletia excelsa Bonpl., ipê-roxo (Tabebuia avellanedae Lorentz ex Griseb e jatobá (Hymenaea courbaril L. Dendrometry of native species in homogeneous stands in the Roraima state: andiroba (Carapa guianensis Aubl, castanha-do-brasil (Bertholletia excelsa Bonpl, ipê-roxo (Tabebuia avellanedae Lorentz ex Griseb and jatobá (Hymenaea courbaril L.

    Directory of Open Access Journals (Sweden)

    Helio Tonini

    2005-09-01

    Full Text Available Estudou-se o crescimento e a seleção de equações para quatro espécies florestais nativas visando identificar espécies promissoras para o plantio em programas de reflorestamentos e em sistemas agroflorestais no Estado de Roraima. O crescimento da andiroba (Carapa guianensis Aubl., da castanha-do-brasil (Bertholletia excelsa Bonpl., do ipê-roxo (Tabebuia avellanedae Lorentz ex Griseb. e do jatobá (Hymenaea courbaril L., aos sete anos de idade, mostrou-se promissor atingindo incrementos médios anuais em volume comercial de 6.3; 14.6; 6.0 e 2.3 m³.ha-1.ano-1, respectivamente. Em relação ao crescimento em diâmetro, todas as espécies apresentaram incrementos médios anuais em diâmetro maiores do que 1 cm, sendo superiores aos observados para árvores crescendo em florestas naturais. A análise estatística, indicou a equação hipsométrica de Prodan como a de melhor ajuste para estimar a altura em função do diâmetro para as quatro espécies analisadas. No entanto, a análise gráfica indicou que a forma da curva altura/diâmetro variou com a espécie sendo necessário o ajuste em separado. O ajuste de equações de volume comercial com casca e fator de forma comercial mostraram ser necessário o ajuste de diferentes equações em função da espécie. A análise gráfica das curvas de volume comercial e fator de forma indicaram que as espécies diferiram em ambos os parâmetros, indicando que a utilização de um fator de forma médio para todas as espécies deve ser evitado, como forma de aumentar a precisão nas estimativas volumétricas.The growth and selection of equations for four native forest species was studied aiming to identify promising species for homogeneous stands, and agroflorestry systems in the Roraima state. The growth of andiroba (Carapa guianensis Aubl., castanha-do-brasil (Bertholletia excelsa Bonpl., ipê-roxo (Tabebuia avellanedae Lorentz ex Griseb and jatobá (Hymenaea courbaril L. to the seven years of age

  3. Media Monopoly in Brazil.

    Science.gov (United States)

    Amaral, Roberto; Guimaraes, Cesar

    1994-01-01

    Documents the process of broadcasting media development in Brazil, the failure of new technologies to produce democratization, and the barriers to democratization erected by monopolization and "metastasis." (SR)

  4. Size distribution and hygroscopic properties of aerosol particles from dry-season biomass burning in Amazonia

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    J. Rissler

    2006-01-01

    Full Text Available Aerosol particle number size distributions and hygroscopic properties were measured at a pasture site in the southwestern Amazon region (Rondonia. The measurements were performed 11 September-14 November 2002 as part of LBA-SMOCC (Large scale Biosphere atmosphere experiment in Amazonia - SMOke aerosols, Clouds, rainfall and Climate, and cover the later part of the dry season (with heavy biomass burning, a transition period, and the onset of the wet period. Particle number size distributions were measured with a DMPS (Differential Mobility Particle Sizer, 3-850nm and an APS (Aerodynamic Particle Sizer, extending the distributions up to 3.3 µm in diameter. An H-TDMA (Hygroscopic Tandem Differential Mobility Analyzer measured the hygroscopic diameter growth factors (Gf at 90% relative humidity (RH, for particles with dry diameters (dp between 20-440 nm, and at several occasions RH scans (30-90% RH were performed for 165nm particles. These data provide the most extensive characterization of Amazonian biomass burning aerosol, with respect to particle number size distributions and hygroscopic properties, presented until now. The evolution of the convective boundary layer over the course of the day causes a distinct diel variation in the aerosol physical properties, which was used to get information about the properties of the aerosol at higher altitudes. The number size distributions averaged over the three defined time periods showed three modes; a nucleation mode with geometrical median diameters (GMD of ~12 nm, an Aitken mode (GMD=61-92 nm and an accumulation mode (GMD=128-190 nm. The two larger modes were shifted towards larger GMD with increasing influence from biomass burning. The hygroscopic growth at 90% RH revealed a somewhat external mixture with two groups of particles; here denoted nearly hydrophobic (Gf~1.09 for 100 nm particles and moderately hygroscopic (Gf~1.26. While the hygroscopic growth factors were surprisingly similar over the

  5. Anthropogenic Emissions Change the Amount and Composition of Organic PM1 in Amazonia

    Science.gov (United States)

    de Sá, S. S.; Palm, B. B.; Campuzano Jost, P.; Day, D. A.; Hu, W.; Isaacman-VanWertz, G. A.; Yee, L.; Wernis, R. A.; Thalman, R.; Brito, J.; Carbone, S.; Artaxo, P.; Goldstein, A. H.; Manzi, A. O.; Souza, R. A. F. D.; Wang, J.; Alexander, M. L. L.; Jimenez, J. L.; Martin, S. T.

    2017-12-01

    processes. Results suggest that polluted conditions are associated with higher organic mass concentrations, with certain pathways being favored to the detriment of others. This analysis and results represent a step toward the goal of improving the understanding of anthropogenic influences on the production of PM1 in Amazonia.

  6. Mayaro virus infection in amazonia: a multimodel inference approach to risk factor assessment.

    Directory of Open Access Journals (Sweden)

    Fernando Abad-Franch

    in village-like areas. This suggests either a vector shift (synanthropic mosquitoes vectoring MAYV or a habitat/habits shift (classical MAYV vectors adapting to densely populated landscapes and nocturnal biting; any such ecological/adaptive novelty could increase the likelihood of MAYV emergence in Amazonia.

  7. Regional N2O fluxes in Amazonia derived from aircraft vertical profiles

    Science.gov (United States)

    D'Amelio, M. T. S.; Gatti, L. V.; Miller, J. B.; Tans, P.

    2009-11-01

    Nitrous oxide (N2O) is the third most important anthropogenic greenhouse gas. Globally, the main sources of N2O are nitrification and denitrification in soils. About two thirds of the soil emissions occur in the tropics and approximately 20% originate in wet rainforest ecosystems, like the Amazon forest. The work presented here involves aircraft vertical profiles of N2O from the surface to 4 km over two sites in the Eastern and Central Amazon: Tapajós National Forest (SAN) and Cuieiras Biologic Reserve (MAN), and the estimation of N2O fluxes for regions upwind of these sites. To our knowledge, these regional scale N2O measurements in Amazonia are unique and represent a new approach to looking regional scale emissions. The fluxes upwind of MAN exhibited little seasonality, and the annual mean was 2.1±1.0 mg N2O m-2 day-1, higher than that for fluxes upwind of SAN, which averaged 1.5±1.6 mg N2O m-2 day-1. The higher rainfall around the MAN site could explain the higher N2O emissions, as a result of increased soil moisture accelerating microbial nitrification and denitrification processes. For fluxes from the coast to SAN seasonality is present for all years, with high fluxes in the months of March through May, and in November through December. The first peak of N2O flux is strongly associated with the wet season. The second peak of high N2O flux recorded at SAN occurs during the dry season and can not be easily explained. However, about half of the dry season profiles exhibit significant correlations with CO, indicating a larger than expected source of N2O from biomass burning. The average CO:N2O ratio for all profiles sampled during the dry season is 94±77 mol CO:mol N2O and suggests a larger biomass burning contribution to the global N2O budget than previously reported.

  8. Hair mercury (signature of fish consumption) and cardiovascular risk in Munduruku and Kayabi Indians of Amazonia.

    Science.gov (United States)

    Dórea, José G; de Souza, Jurandir R; Rodrigues, Patricia; Ferrari, Iris; Barbosa, Antonio C

    2005-02-01

    Fish is an important natural resource in the diet of inhabitants of the Amazon rain forest and a marker of its consumption (hair Hg) was used to compare selected cardiovascular risk parameters between tribes of Eastern Amazonia. Three Munduruku (Terra Preta, Kaburua, Cururu) villages and one Kayabi village at the banks of head rivers (Tapajos, Tropas, Kabitutu, Cururu, Curuzinho, Teles Pires) of the Tapajos Basin were studied in relation to fish Hg concentrations, mercury in hair (fish consumption) and erythrocytes, body mass index (height/weight, kg/cm2), and blood pressure. The mean fish Hg concentrations were higher in predatory (578.6 ng/g) than in nonpredatory species (52.8 ng/g). Overall only 26% of fish Hg concentrations were above 500 ng/g, and only 11% were above 1000 ng/g. There was no systematic trend in fish Hg concentrations from rivers with a history of gold-mining activities. The biomarker of fish consumption (hair Hg) was significantly associated with erythrocyte-Hg (r=0.5181; P=0.0001) and was significantly higher in Kayabi (12.7 microg/g) than in the Munduruku (3.4 microg/g). Biomarker-assessed fish consumption rate was higher in the Kayabi (110 g/day) than in the Munduruku villages (30 g/day). Although no significant differences in body mass index (BMI) were observed between tribes, there was a trend of lower increase in blood pressure with age among the higher fish consumers (Kayabi). Summary clinical evaluation did not detect neurologic complaints compatible with Hg intoxication (paraparesis, numbness, tremor, balancing failure), but endemic tropical diseases such as clinical history of malaria showed a high prevalence (55.4%). Fish is an abundant natural resource, important in the Indian diet, that has been historically consumed without perceived problems and can easily be traced through hair Hg. The exposure to freshwater fish monomethyl mercury is less of an issue than endemic infectious diseases such as malaria and lack of basic medical

  9. Measuring local depletion of terrestrial game vertebrates by central-place hunters in rural Amazonia.

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    Mark I Abrahams

    Full Text Available The degree to which terrestrial vertebrate populations are depleted in tropical forests occupied by human communities has been the subject of an intense polarising debate that has important conservation implications. Conservation ecologists and practitioners are divided over the extent to which community-based subsistence offtake is compatible with ecologically functional populations of tropical forest game species. To quantify depletion envelopes of forest vertebrates around human communities, we deployed a total of 383 camera trap stations and 78 quantitative interviews to survey the peri-community areas controlled by 60 semi-subsistence communities over a combined area of over 3.2 million hectares in the Médio Juruá and Uatumã regions of Central-Western Brazilian Amazonia. Our results largely conform with prior evidence that hunting large-bodied vertebrates reduces wildlife populations near settlements, such that they are only found at a distance to settlements where they are hunted less frequently. Camera trap data suggest that a select few harvest-sensitive species, including lowland tapir, are either repelled or depleted by human communities. Nocturnal and cathemeral species were detected relatively more frequently in disturbed areas close to communities, but individual species did not necessarily shift their activity patterns. Group biomass of all species was depressed in the wider neighbourhood of urban areas rather than communities. Interview data suggest that species traits, especially group size and body mass, mediate these relationships. Large-bodied, large-group-living species are detected farther from communities as reported by experienced informants. Long-established communities in our study regions have not "emptied" the surrounding forest. Low human population density and low hunting offtake due to abundant sources of alternative aquatic protein, suggest that these communities represent a best-case scenario for sustainable

  10. Measuring local depletion of terrestrial game vertebrates by central-place hunters in rural Amazonia

    Science.gov (United States)

    Peres, Carlos A.; Costa, Hugo C. M.

    2017-01-01

    The degree to which terrestrial vertebrate populations are depleted in tropical forests occupied by human communities has been the subject of an intense polarising debate that has important conservation implications. Conservation ecologists and practitioners are divided over the extent to which community-based subsistence offtake is compatible with ecologically functional populations of tropical forest game species. To quantify depletion envelopes of forest vertebrates around human communities, we deployed a total of 383 camera trap stations and 78 quantitative interviews to survey the peri-community areas controlled by 60 semi-subsistence communities over a combined area of over 3.2 million hectares in the Médio Juruá and Uatumã regions of Central-Western Brazilian Amazonia. Our results largely conform with prior evidence that hunting large-bodied vertebrates reduces wildlife populations near settlements, such that they are only found at a distance to settlements where they are hunted less frequently. Camera trap data suggest that a select few harvest-sensitive species, including lowland tapir, are either repelled or depleted by human communities. Nocturnal and cathemeral species were detected relatively more frequently in disturbed areas close to communities, but individual species did not necessarily shift their activity patterns. Group biomass of all species was depressed in the wider neighbourhood of urban areas rather than communities. Interview data suggest that species traits, especially group size and body mass, mediate these relationships. Large-bodied, large-group-living species are detected farther from communities as reported by experienced informants. Long-established communities in our study regions have not “emptied” the surrounding forest. Low human population density and low hunting offtake due to abundant sources of alternative aquatic protein, suggest that these communities represent a best-case scenario for sustainable hunting of

  11. Trabajo y relaciones laborales en los enclaves minero-metalúrgicos de la Amazonia

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    Josep Pont Vidal

    2008-04-01

    Full Text Available Abstract:  Labour and labour relations in the enclaves of metallurgical mining in the AmazonThis article is based upon an empirical study of  life and labour conditions in the metallurgical  mining enclaves of the eastern Amazon region.  From the perspective of civil society (associations  of workers, labour conditions are analysed according to interviews with workers and their  family members given outside the work sphere.  Using the method based on ‘grounded theory’, and specifically on the qualitative analysis of  theorization, a scheme of two levels has been  made: the ‘situational activity’ and the ‘subjectivization of the activity’. The first level, the ‘situational activity’, is centred in the sphere of the  organizations of workers and their perceptions  and strategies for action. The second level, the  ‘subjective of the activity’, addresses the subjective interpretations adopted by workers and their  families. Resumen:Este escrito se basa en un estudio empírico de las  condiciones de vida y relaciones laborales en los  enclaves minero-metalúrgicos de la Amazonia  oriental. En él se analizan las condiciones laborales desde la perspectiva de la sociedad civil (asociaciones de trabajadores, recurriendo para ello a  entrevistas con trabajadores y sus familias fuera  del ambiente de trabajo. A partir del método basado en la teorización anclada, y específicamente  en el denominado análisis cualitativo de teorización, se ha confeccionado un esquema de dos  niveles: la ‘actividad situacional’, y la ‘subjetivización de la actividad’. El primer nivel -la ‘actividad situacional’- se centra en la esfera de las  organizaciones de trabajadores y sus ideas y estrategias de acción. El segundo nivel -la ‘subjetivización de la actividad’- trata las interpretaciones  subjetivas adoptadas por los trabajadores y sus  familias.

  12. El lugar y el papel de la Or ganización del Tratado de Cooperación Amazónica (OTCA en la geopolítica brasileña y sudamericana - The place and role of the Amazon Cooperation Treaty Organization (ACTO in the geopolitics of South America and Brazil

    Directory of Open Access Journals (Sweden)

    BORBÉLY, Anikó

    2014-06-01

    Full Text Available The geopolitics is a teory evolved in the beginning of the 20th century, part of the political geography that examines the international relations and makes scientific investigations about relationships of the countries. South America is one of the most important geopolitical zones of the World. In its future it will be very important how the countries of the southern hemisphere can utilize and make the best forms of the regional integration of economy and trade. If Amazonia will become a ’true common interest and case’, it may be an example for the (subregional integration of the ’most recent and soft’ problems. Such as, protection of environment and forest, protection of the biodiversity, waterpolicy etc. In this process Brazil has a very important role in the case of Amazonia. The gradual destruction of this region has diverse consequences. On the basis of these Amazonia and the thinking about the South American territory is becoming even more important.

  13. Global warming in Amazonia: impacts and Mitigation Aquecimento Global na Amazônia: impactos e Mitigação

    Directory of Open Access Journals (Sweden)

    Philip Martin Fearnside

    2009-01-01

    Full Text Available Global warming has potentially catastrophic impacts in Amazonia, while at the same time maintenance of the Amazon forest offers one of the most valuable and cost-effective options for mitigating climate change. We know that the El Niño phenomenon, caused by temperature oscillations of surface water in the Pacific, has serious impacts in Amazonia, causing droughts and forest fires (as in 1997-1998. Temperature oscillations in the Atlantic also provoke severe droughts (as in 2005. We also know that Amazonian trees die both from fires and from water stress under hot, dry conditions. In addition, water recycled through the forest provides rainfall that maintains climatic conditions appropriate for tropical forest, especially in the dry season. What we need to know quickly, through intensified research, includes progress in representing El Niño and the Atlantic oscillations in climatic models, representation of biotic feedbacks in models used for decision-making about global warming, and narrowing the range of estimating climate sensitivity to reduce uncertainty about the probability of very severe impacts. Items that need to be negotiated include the definition of "dangerous" climate change, with the corresponding maximum levels of greenhouse gases in the atmosphere. Mitigation of global warming must include maintaining the Amazon forest, which has benefits for combating global warming from two separate roles: cutting the flow the emissions of carbon each year from the rapid pace of deforestation, and avoiding emission of the stock of carbon in the remaining forest that can be released by various ways, including climate change itself. Barriers to rewarding forest maintenance include the need for financial rewards for both of these roles. Other needs are for continued reduction of uncertainty regarding emissions and deforestation processes, as well as agreement on the basis of carbon accounting. As one of the countries most subject to impacts of

  14. Convergent Adaptations: Bitter Manioc Cultivation Systems in Fertile Anthropogenic Dark Earths and Floodplain Soils in Central Amazonia

    Science.gov (United States)

    Fraser, James Angus; Alves-Pereira, Alessandro; Junqueira, André Braga; Peroni, Nivaldo; Clement, Charles Roland

    2012-01-01

    Shifting cultivation in the humid tropics is incredibly diverse, yet research tends to focus on one type: long-fallow shifting cultivation. While it is a typical adaptation to the highly-weathered nutrient-poor soils of the Amazonian terra firme, fertile environments in the region offer opportunities for agricultural intensification. We hypothesized that Amazonian people have developed divergent bitter manioc cultivation systems as adaptations to the properties of different soils. We compared bitter manioc cultivation in two nutrient-rich and two nutrient-poor soils, along the middle Madeira River in Central Amazonia. We interviewed 249 farmers in 6 localities, sampled their manioc fields, and carried out genetic analysis of bitter manioc landraces. While cultivation in the two richer soils at different localities was characterized by fast-maturing, low-starch manioc landraces, with shorter cropping periods and shorter fallows, the predominant manioc landraces in these soils were generally not genetically similar. Rather, predominant landraces in each of these two fertile soils have emerged from separate selective trajectories which produced landraces that converged for fast-maturing low-starch traits adapted to intensified swidden systems in fertile soils. This contrasts with the more extensive cultivation systems found in the two poorer soils at different localities, characterized by the prevalence of slow-maturing high-starch landraces, longer cropping periods and longer fallows, typical of previous studies. Farmers plant different assemblages of bitter manioc landraces in different soils and the most popular landraces were shown to exhibit significantly different yields when planted in different soils. Farmers have selected different sets of landraces with different perceived agronomic characteristics, along with different fallow lengths, as adaptations to the specific properties of each agroecological micro-environment. These findings open up new avenues for

  15. Convergent adaptations: bitter manioc cultivation systems in fertile anthropogenic dark earths and floodplain soils in Central Amazonia.

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    James Angus Fraser

    Full Text Available Shifting cultivation in the humid tropics is incredibly diverse, yet research tends to focus on one type: long-fallow shifting cultivation. While it is a typical adaptation to the highly-weathered nutrient-poor soils of the Amazonian terra firme, fertile environments in the region offer opportunities for agricultural intensification. We hypothesized that Amazonian people have developed divergent bitter manioc cultivation systems as adaptations to the properties of different soils. We compared bitter manioc cultivation in two nutrient-rich and two nutrient-poor soils, along the middle Madeira River in Central Amazonia. We interviewed 249 farmers in 6 localities, sampled their manioc fields, and carried out genetic analysis of bitter manioc landraces. While cultivation in the two richer soils at different localities was characterized by fast-maturing, low-starch manioc landraces, with shorter cropping periods and shorter fallows, the predominant manioc landraces in these soils were generally not genetically similar. Rather, predominant landraces in each of these two fertile soils have emerged from separate selective trajectories which produced landraces that converged for fast-maturing low-starch traits adapted to intensified swidden systems in fertile soils. This contrasts with the more extensive cultivation systems found in the two poorer soils at different localities, characterized by the prevalence of slow-maturing high-starch landraces, longer cropping periods and longer fallows, typical of previous studies. Farmers plant different assemblages of bitter manioc landraces in different soils and the most popular landraces were shown to exhibit significantly different yields when planted in different soils. Farmers have selected different sets of landraces with different perceived agronomic characteristics, along with different fallow lengths, as adaptations to the specific properties of each agroecological micro-environment. These findings open

  16. [Distribution patterns of canopy and understory tree species at local scale in a Tierra Firme forest, the Colombian Amazonia].

    Science.gov (United States)

    Barreto-Silva, Juan Sebastian; López, Dairon Cárdenas; Montoya, Alvaro Javier Duque

    2014-03-01

    The effect of environmental variation on the structure of tree communities in tropical forests is still under debate. There is evidence that in landscapes like Tierra Firme forest, where the environmental gradient decreases at a local level, the effect of soil on the distribution patterns of plant species is minimal, happens to be random or is due to biological processes. In contrast, in studies with different kinds of plants from tropical forests, a greater effect on floristic composition of varying soil and topography has been reported. To assess this, the current study was carried out in a permanent plot of ten hectares in the Amacayacu National Park, Colombian Amazonia. To run the analysis, floristic and environmental variations were obtained according to tree species abundance categories and growth forms. In order to quantify the role played by both environmental filtering and dispersal limitation, the variation of the spatial configuration was included. We used Detrended Correspondence Analysis and Canonical Correspondence Analysis, followed by a variation partitioning, to analyze the species distribution patterns. The spatial template was evaluated using the Principal Coordinates of Neighbor Matrix method. We recorded 14 074 individuals from 1 053 species and 80 families. The most abundant families were Myristicaceae, Moraceae, Meliaceae, Arecaceae and Lecythidaceae, coinciding with other studies from Northwest Amazonia. Beta diversity was relatively low within the plot. Soils were very poor, had high aluminum concentration and were predominantly clayey. The floristic differences explained along the ten hectares plot were mainly associated to biological processes, such as dispersal limitation. The largest proportion of community variation in our dataset was unexplained by either environmental or spatial data. In conclusion, these results support random processes as the major drivers of the spatial variation of tree species at a local scale on Tierra Firme

  17. Biodiversidad en espacios productivos y los aspectos sociales de las comunidades ribereñas de la Amazonia Occidental

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    Williane Maria de Oliveira Martins

    2014-03-01

    Full Text Available Los sistemas agrícolas ribereño representan una alternativa de producción sustentable para las comunidades tradicionales de la Amazonia, especialmente en cuanto a la diversidad de productos y la generación de ingresos. Por lo tanto, teniendo en cuenta las funciones ecológicas y sociales el propósito de este estudio fue analizar las áreas productivas y aspectos etnosociais de las comunidades ribereñas de la lejano Amazonia Occidental, Acre, Brasil. La recolección de datos se realizó a través de entrevistas participativas, formales e inductivo después de un cuestionario semi-estructurado. Toda la información recogida se transfiere a una base de datos electrónica, que sistematizado y procesado. Los sistemas agrícolas en estas comunidades son los cultivos y quintales. Los cultivos tienen una especie agrodiversidad en la misma zona, el producto principal es el cultivo de la yuca. Los quintales tienen arreglos espaciales de especies frutales, medicinales y sobre todo los cultivos de hortalizas. Así, tanto los astilleros como los claros son responsables de la sostenibilidad de las familias ribereñas de esta comunidad, sirviendo de subsistencia y asistencia económica.Por otra parte, se trata de ser una alternativa adaptada a las condiciones de los ecosistemas agrícolas llanura de inundación en la región.

  18. Seasonality of isoprenoid emissions from a primary rainforest in central Amazonia

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    E. G. Alves

    2016-03-01

    Full Text Available Tropical rainforests are an important source of isoprenoid and other volatile organic compound (VOC emissions to the atmosphere. The seasonal variation of these compounds is however still poorly understood. In this study, vertical profiles of mixing ratios of isoprene, total monoterpenes and total sesquiterpenes, were measured within and above the canopy, in a primary rainforest in central Amazonia, using a proton transfer reaction – mass spectrometer (PTR-MS. Fluxes of these compounds from the canopy into the atmosphere were estimated from PTR-MS measurements by using an inverse Lagrangian transport model. Measurements were carried out continuously from September 2010 to January 2011, encompassing the dry and wet seasons. Mixing ratios were higher during the dry (isoprene – 2.68 ± 0.9 ppbv, total monoterpenes – 0.67 ± 0.3 ppbv; total sesquiterpenes – 0.09 ± 0.07 ppbv than the wet season (isoprene – 1.66 ± 0.9 ppbv, total monoterpenes – 0.47 ± 0.2 ppbv; total sesquiterpenes – 0.03 ± 0.02 ppbv for all compounds. Ambient air temperature and photosynthetically active radiation (PAR behaved similarly. Daytime isoprene and total monoterpene mixing ratios were highest within the canopy, rather than near the ground or above the canopy. By comparison, daytime total sesquiterpene mixing ratios were highest near the ground. Daytime fluxes varied significantly between seasons for all compounds. The maximums for isoprene (2.53 ± 0.5 µmol m−2 h−1 and total monoterpenes (1.77 ± 0.05 µmol m−2 h−1 were observed in the late dry season, whereas the maximum for total sesquiterpenes was found during the dry-to-wet transition season (0.77 ± 0.1 µmol m−2 h−1. These flux estimates suggest that the canopy is the main source of isoprenoids emitted into the atmosphere for all seasons. However, uncertainties in turbulence parameterization near the ground could affect estimates of fluxes that come from the ground. Leaf

  19. Seasonality of isoprenoid emissions from a primary rainforest in central Amazonia

    Science.gov (United States)

    Alves, Eliane G.; Jardine, Kolby; Tota, Julio; Jardine, Angela; Yãnez-Serrano, Ana Maria; Karl, Thomas; Tavares, Julia; Nelson, Bruce; Gu, Dasa; Stavrakou, Trissevgeni; Martin, Scot; Artaxo, Paulo; Manzi, Antonio; Guenther, Alex

    2016-03-01

    Tropical rainforests are an important source of isoprenoid and other volatile organic compound (VOC) emissions to the atmosphere. The seasonal variation of these compounds is however still poorly understood. In this study, vertical profiles of mixing ratios of isoprene, total monoterpenes and total sesquiterpenes, were measured within and above the canopy, in a primary rainforest in central Amazonia, using a proton transfer reaction - mass spectrometer (PTR-MS). Fluxes of these compounds from the canopy into the atmosphere were estimated from PTR-MS measurements by using an inverse Lagrangian transport model. Measurements were carried out continuously from September 2010 to January 2011, encompassing the dry and wet seasons. Mixing ratios were higher during the dry (isoprene - 2.68 ± 0.9 ppbv, total monoterpenes - 0.67 ± 0.3 ppbv; total sesquiterpenes - 0.09 ± 0.07 ppbv) than the wet season (isoprene - 1.66 ± 0.9 ppbv, total monoterpenes - 0.47 ± 0.2 ppbv; total sesquiterpenes - 0.03 ± 0.02 ppbv) for all compounds. Ambient air temperature and photosynthetically active radiation (PAR) behaved similarly. Daytime isoprene and total monoterpene mixing ratios were highest within the canopy, rather than near the ground or above the canopy. By comparison, daytime total sesquiterpene mixing ratios were highest near the ground. Daytime fluxes varied significantly between seasons for all compounds. The maximums for isoprene (2.53 ± 0.5 µmol m-2 h-1) and total monoterpenes (1.77 ± 0.05 µmol m-2 h-1) were observed in the late dry season, whereas the maximum for total sesquiterpenes was found during the dry-to-wet transition season (0.77 ± 0.1 µmol m-2 h-1). These flux estimates suggest that the canopy is the main source of isoprenoids emitted into the atmosphere for all seasons. However, uncertainties in turbulence parameterization near the ground could affect estimates of fluxes that come from the ground. Leaf phenology seemed to be an important driver of seasonal

  20. Vegetation and hydrology changes in Eastern Amazonia inferred from a pollen record

    Directory of Open Access Journals (Sweden)

    Mauro B. de Toledo

    2008-03-01

    Full Text Available Pollen, charcoal, and C14 analyses were performed on a sediment core obtained from Lake Tapera (Amapá to provide the palaeoenvironmental history of this part of Amazonia. A multivariate analysis technique, Detrended Correspondence Analysis, was applied to the pollen data to improve visualization of sample distribution and similarity. A sedimentary hiatus lasting 5,500 years was identified in the Lake Tapera. Because the timing of the hiatus overlapped with the highest Holocene sea-level, which would have increased the local water table preventing the lake from drying out, it is clear that sea-level was not important in maintaining the lake level. Lake Tapera probably depended on riverine flood waters, and the sedimentary gap was caused by reduced Amazon River discharge, due to an extremely dry period in the Andes (8,000-5,000 years BP, when precipitation levels markedly decreased. The lack of Andean pollen (river transported in the record after this event supports this interpretation. The pollen analysis shows that when sedimentation resumed in 1,620 cal. years BP, the vegetation around the lake was changed from forest into savanna. This record demonstrates the need to improve our understanding of climate changes and their associated impacts on vegetation dynamics.Análises de pólen, carvões e datações C foram conduzidas em um testemunho coletado no lago Tapera (Amapá com o objetivo de interpretar a história paleoambiental desta parte da Amazônia. Uma das técnicas de análises multivariadas, Análise de Correspondência Destendenciada (DCA, foi utilizada a fim de melhor visualizar a distribuição e similaridade das amostras. Foi identificado um hiato sedimentar com duração de 5.500 anos no lago Tapera. Como o hiato ocorreu simultaneamente ao nível do mar mais alto do Holoceno, o que deveria ter aumentado o lençol freático, impedindo assim o lago de secar, é evidente que variações do nível do mar não foram importantes na

  1. Cogeneration for Brazil

    International Nuclear Information System (INIS)

    Anon.

    2000-01-01

    Almost all the electric power in Brazil comes from large-scale hydroelectric plants: only about 3% comes from cogeneration. But, now that the barriers which discouraged cogeneration are being removed, there will be more and more investment in cogeneration and distributed generation. The circumstances which have brought about these changes are described. It is expected that cogeneration will be responsible for producing 10-15% of Brazil's electricity by 2010 and the demand for cogeneration will reach 11-17 GW. It is concluded that Brazil represents one of the world's most attractive market for cogeneration and distributed generation

  2. Vertebrate roadkills on State Highway 383, Rondônia, Brazil.

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Batista Turci

    2009-03-01

    Full Text Available Roadkills are a serious threat to many species of wildlife worldwide. In Brazil, few studies are available about the importance of roadkills. Information about roadkills in Amazonia are even more scarce when compared to central and southern Brazil. Here we describe the vertebrate roadkills on State Highway 383 in Rondônia. From May 2004 – April 2005, thirty samples were taken the along 110km of the highway between Cacoal and Alta Floresta D’Oeste. Thirty-four vertebrate species were found in 259 specimens. In terms of absolute numbers, amphibians were the most frequent roadkills, with 68 individuals of two species. Birds followed, with 67 individuals of 12 species, then reptiles (67 indiv., 12 species and mammals (63 indiv.,13 species. Eight species (Leptodactylus gr. pentadactylus, Rhinella sp, Amphisbaena sp., Liophis reginae, Crotophaga ani, Didelphis marsupialis, Euphractus sexcinctus and Cerdocyon thous were the most frequent roadkills, accounting for 76% of the vertebrate roadkills. More than half of the roadkills occurred during the dry season.

  3. Reptiles from Lençóis Maranhenses National Park, Maranhão, northeastern Brazil

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    Jivanildo Miranda

    2012-11-01

    Full Text Available We are presenting a list of the reptile species from Lençóis Maranhenses National Park (LMNP, Maranhão, Brazil, obtained during 235 days of field work. The study area is located in the contact zone between three major Neotropical ecosystems: Amazonia, Caatinga, and Cerrado. The PNLM encompasses the largest dune fields in Brazil, wide shrubby areas (restingas, lakes, mangroves, and many freshwater lagoons. We have recorded 42 species of reptiles in the area: 24 snakes, 12 lizards, two worm lizards, three turtles, and one alligator. About 81 % of the recorded species occurred only in restinga areas. Our data highlights the uniqueness of the PNLM in the context of the biomes that surround it and shows the importance of efforts to improve the conservation of reptiles living in the restinga, which currently comprise only about 20 % of the total area protected by the park, but which are the mesohabitat containing most of the reptile species in the Lençóis Maranhenses complex of habitats.

  4. Reptiles from Lençóis Maranhenses National Park, Maranhão, northeastern Brazil.

    Science.gov (United States)

    Miranda, Jivanildo Pinheiro; Costa, João Carlos Lopes; Rocha, Carlos Frederico D

    2012-01-01

    We are presenting a list of the reptile species from Lençóis Maranhenses National Park (LMNP), Maranhão, Brazil, obtained during 235 days of field work. The study area is located in the contact zone between three major Neotropical ecosystems: Amazonia, Caatinga, and Cerrado. The PNLM encompasses the largest dune fields in Brazil, wide shrubby areas (restingas), lakes, mangroves, and many freshwater lagoons. We have recorded 42 species of reptiles in the area: 24 snakes, 12 lizards, two worm lizards, three turtles, and one alligator. About 81 % of the recorded species occurred only in restinga areas. Our data highlights the uniqueness of the PNLM in the context of the biomes that surround it and shows the importance of efforts to improve the conservation of reptiles living in the restinga, which currently comprise only about 20 % of the total area protected by the park, but which are the mesohabitat containing most of the reptile species in the Lençóis Maranhenses complex of habitats.

  5. New species and geographical records of dactylogyrids (Monogenea) of catfish (Siluriformes) from the Peruvian Amazonia

    Czech Academy of Sciences Publication Activity Database

    Mendoza-Palmero, Carlos Alonso; Scholz, Tomáš; Mendoza-Franco, E. F.; Kuchta, Roman

    2012-01-01

    Roč. 98, č. 3 (2012), s. 484-497 ISSN 0022-3395 R&D Projects: GA MŠk LC522; GA ČR GBP505/12/G112; GA ČR GD206/09/H026 Institutional research plan: CEZ:AV0Z60220518 Keywords : PARANA RIVER FLOODPLAIN * DEMIDOSPERMUS DACTYLOGYRIDAE * NEOTROPICAL MONOGENEA * ALINEMA-AMAZONICUM * TAPEWORMS CESTODA * GEN N * ANCYROCEPHALINAE * FISHES * BRAZIL * GILLS Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.321, year: 2012 http://www.bioone.org/doi/abs/10.1645/GE-2941.1

  6. CCN activity and organic hygroscopicity of aerosols downwind of an urban region in central Amazonia: seasonal and diel variations and impact of anthropogenic emissions

    Science.gov (United States)

    Thalman, Ryan; de Sá, Suzane S.; Palm, Brett B.; Barbosa, Henrique M. J.; Pöhlker, Mira L.; Lizabeth Alexander, M.; Brito, Joel; Carbone, Samara; Castillo, Paulo; Day, Douglas A.; Kuang, Chongai; Manzi, Antonio; Ng, Nga Lee; Sedlacek, Arthur J., III; Souza, Rodrigo; Springston, Stephen; Watson, Thomas; Pöhlker, Christopher; Pöschl, Ulrich; Andreae, Meinrat O.; Artaxo, Paulo; Jimenez, Jose L.; Martin, Scot T.; Wang, Jian

    2017-10-01

    During the Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) campaign, size-resolved cloud condensation nuclei (CCN) spectra were characterized at a research site (T3) 60 km downwind of the city of Manaus, Brazil, in central Amazonia for 1 year (12 March 2014 to 3 March 2015). Particle hygroscopicity (κCCN) and mixing state were derived from the size-resolved CCN spectra, and the hygroscopicity of the organic component of the aerosol (κorg) was then calculated from κCCN and concurrent chemical composition measurements. The annual average κCCN increased from 0.13 at 75 nm to 0.17 at 171 nm, and the increase was largely due to an increase in sulfate volume fraction. During both wet and dry seasons, κCCN, κorg, and particle composition under background conditions exhibited essentially no diel variations. The constant κorg of ˜ 0. 15 is consistent with the largely uniform and high O : C value (˜ 0. 8), indicating that the aerosols under background conditions are dominated by the aged regional aerosol particles consisting of highly oxygenated organic compounds. For air masses strongly influenced by urban pollution and/or local biomass burning, lower values of κorg and organic O : C atomic ratio were observed during night, due to accumulation of freshly emitted particles, dominated by primary organic aerosol (POA) with low hygroscopicity, within a shallow nocturnal boundary layer. The O : C, κorg, and κCCN increased from the early morning hours and peaked around noon, driven by the formation and aging of secondary organic aerosol (SOA) and dilution of POA emissions into a deeper boundary layer, while the development of the boundary layer, which leads to mixing with aged particles from the residual layer aloft, likely also contributed to the increases. The hygroscopicities associated with individual organic factors, derived from PMF (positive matrix factorization) analysis of AMS (aerosol mass spectrometry) spectra, were estimated through

  7. CCN activity and organic hygroscopicity of aerosols downwind of an urban region in central Amazonia: seasonal and diel variations and impact of anthropogenic emissions

    Directory of Open Access Journals (Sweden)

    R. Thalman

    2017-10-01

    Full Text Available During the Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5 campaign, size-resolved cloud condensation nuclei (CCN spectra were characterized at a research site (T3 60 km downwind of the city of Manaus, Brazil, in central Amazonia for 1 year (12 March 2014 to 3 March 2015. Particle hygroscopicity (κCCN and mixing state were derived from the size-resolved CCN spectra, and the hygroscopicity of the organic component of the aerosol (κorg was then calculated from κCCN and concurrent chemical composition measurements. The annual average κCCN increased from 0.13 at 75 nm to 0.17 at 171 nm, and the increase was largely due to an increase in sulfate volume fraction. During both wet and dry seasons, κCCN, κorg, and particle composition under background conditions exhibited essentially no diel variations. The constant κorg of ∼ 0. 15 is consistent with the largely uniform and high O : C value (∼ 0. 8, indicating that the aerosols under background conditions are dominated by the aged regional aerosol particles consisting of highly oxygenated organic compounds. For air masses strongly influenced by urban pollution and/or local biomass burning, lower values of κorg and organic O : C atomic ratio were observed during night, due to accumulation of freshly emitted particles, dominated by primary organic aerosol (POA with low hygroscopicity, within a shallow nocturnal boundary layer. The O : C, κorg, and κCCN increased from the early morning hours and peaked around noon, driven by the formation and aging of secondary organic aerosol (SOA and dilution of POA emissions into a deeper boundary layer, while the development of the boundary layer, which leads to mixing with aged particles from the residual layer aloft, likely also contributed to the increases. The hygroscopicities associated with individual organic factors, derived from PMF (positive matrix factorization analysis of AMS (aerosol mass

  8. Anaplasma marginale infection in cattle from south-western Amazonia Infecção por Anaplasma marginale em bovinos na Amazônia Sul Ocidental, Brasil

    Directory of Open Access Journals (Sweden)

    Luciana Gatto Brito

    2010-03-01

    Full Text Available The present study provides the first epidemiological data regarding infection by Anaplasma marginale in cattle reared in south-western Brazilian Amazonia. One simple procedure was adapted for the extraction of DNA from blood clots collected in seven microregions of Rondônia State and two mesoregions of Acre State. PCR method was used to asses the frequency of A. marginale infections in 4 to12-month-old cattle. The cattle infection was investigated by polymerase chain reaction (PCR using the specific primer "msp5" for A. marginale. The DNA amplifications revealed that the mean frequency of A. marginale infection was 98.6% (1,627/1,650 in samples from Rondonia, and 92.87% (208/225 in samples from Acre. The high frequency of A. marginale infections in 4 to 12-month-old cattle indicate a situation of enzootic stability in the studied areas and are comparable to those detected by immunodiagnosis in different endemic regions in Brazil. The DNA extraction of clotted blood method described here can be used for epidemiological studies on anaplasmosis and other bovine hemoparasites.O presente estudo fornece os primeiros dados epidemiológicos relativos a infecção por Anaplasma marginale em bovinos criados na Amazônia Sul Ocidental brasileira. Foi adaptado um procedimento simples para a extração de DNA a partir de coágulos sanguíneos coletados em sete microrregiões do estado de Rondônia e duas mesoregiões do estado do Acre. A técnica da reação em cadeia da polimerase (PCR foi aplicada para avaliar a freqüência da infecção por A. marginale em bovinos com idade entre 4 e 12 meses. Após a extração do DNA de cada amostra, a infecção nos bovinos foi investigada pela amplificação do gene "msp5" de A. marginale. As técnicas de amplificação do DNA revelaram que a freqüência de infecção por A. marginale foi de 98,6% (1.627/1.650 nas amostras provenientes de Rondônia e de 92,87% (208/225 nas amostras do Acre. A alta freqüência da

  9. First typology of cacao (Theobroma cacao L.) systems in Colombian Amazonia, based on tree species richness, canopy structure and light availability.

    Science.gov (United States)

    Suárez Salazar, Juan Carlos; Ngo Bieng, Marie Ange; Melgarejo, Luz Marina; Di Rienzo, Julio A; Casanoves, Fernando

    2018-01-01

    We present a typology of cacao agroforest systems in Colombian Amazonia. These systems had yet to be described in the literature, especially their potential in terms of biodiversity conservation. The systems studied are located in a post-conflict area, and a deforestation front in Colombian Amazonia. Cacao cropping systems are of key importance in Colombia: cacao plays a prime role in post conflict resolution, as cacao is a legal crop to replace illegal crops; cacao agroforests are expected to be a sustainable practice, promoting forest-friendly land use. We worked in 50 x 2000 m2 agroforest plots, in Colombian Amazonia. A cluster analysis was used to build a typology based on 28 variables characterised in each plot, and related to diversity, composition, spatial structure and light availability for the cacao trees. We included variables related to light availability to evaluate the amount of transmitted radiation to the cacao trees in each type, and its suitability for cacao ecophysiological development. We identified 4 types of cacao agroforests based on differences concerning tree species diversity and the impact of canopy spatial structure on light availability for the cacao trees in the understorey. We found 127 tree species in the dataset, with some exclusive species in each type. We also found that 3 out of the 4 types identified displayed an erosion of tree species diversity. This reduction in shade tree species may have been linked to the desire to reduce shade, but we also found that all the types described were compatible with good ecophysiological development of the cacao trees. Cacao agroforest systems may actually be achieving biodiversity conservation goals in Colombian Amazonia. One challenging prospect will be to monitor and encourage the conservation of tree species diversity in cacao agroforest systems during the development of these cropping systems, as a form of forest-friendly management enhancing sustainable peace building in Colombia.

  10. First typology of cacao (Theobroma cacao L.) systems in Colombian Amazonia, based on tree species richness, canopy structure and light availability

    Science.gov (United States)

    Suárez Salazar, Juan Carlos; Melgarejo, Luz Marina; Di Rienzo, Julio A.; Casanoves, Fernando

    2018-01-01

    Aim and background We present a typology of cacao agroforest systems in Colombian Amazonia. These systems had yet to be described in the literature, especially their potential in terms of biodiversity conservation. The systems studied are located in a post-conflict area, and a deforestation front in Colombian Amazonia. Cacao cropping systems are of key importance in Colombia: cacao plays a prime role in post conflict resolution, as cacao is a legal crop to replace illegal crops; cacao agroforests are expected to be a sustainable practice, promoting forest-friendly land use. Material and methods We worked in 50 x 2000 m2 agroforest plots, in Colombian Amazonia. A cluster analysis was used to build a typology based on 28 variables characterised in each plot, and related to diversity, composition, spatial structure and light availability for the cacao trees. We included variables related to light availability to evaluate the amount of transmitted radiation to the cacao trees in each type, and its suitability for cacao ecophysiological development. Main results We identified 4 types of cacao agroforests based on differences concerning tree species diversity and the impact of canopy spatial structure on light availability for the cacao trees in the understorey. We found 127 tree species in the dataset, with some exclusive species in each type. We also found that 3 out of the 4 types identified displayed an erosion of tree species diversity. This reduction in shade tree species may have been linked to the desire to reduce shade, but we also found that all the types described were compatible with good ecophysiological development of the cacao trees. Main conclusions and prospects Cacao agroforest systems may actually be achieving biodiversity conservation goals in Colombian Amazonia. One challenging prospect will be to monitor and encourage the conservation of tree species diversity in cacao agroforest systems during the development of these cropping systems, as a form of

  11. First typology of cacao (Theobroma cacao L. systems in Colombian Amazonia, based on tree species richness, canopy structure and light availability.

    Directory of Open Access Journals (Sweden)

    Juan Carlos Suárez Salazar

    Full Text Available We present a typology of cacao agroforest systems in Colombian Amazonia. These systems had yet to be described in the literature, especially their potential in terms of biodiversity conservation. The systems studied are located in a post-conflict area, and a deforestation front in Colombian Amazonia. Cacao cropping systems are of key importance in Colombia: cacao plays a prime role in post conflict resolution, as cacao is a legal crop to replace illegal crops; cacao agroforests are expected to be a sustainable practice, promoting forest-friendly land use.We worked in 50 x 2000 m2 agroforest plots, in Colombian Amazonia. A cluster analysis was used to build a typology based on 28 variables characterised in each plot, and related to diversity, composition, spatial structure and light availability for the cacao trees. We included variables related to light availability to evaluate the amount of transmitted radiation to the cacao trees in each type, and its suitability for cacao ecophysiological development.We identified 4 types of cacao agroforests based on differences concerning tree species diversity and the impact of canopy spatial structure on light availability for the cacao trees in the understorey. We found 127 tree species in the dataset, with some exclusive species in each type. We also found that 3 out of the 4 types identified displayed an erosion of tree species diversity. This reduction in shade tree species may have been linked to the desire to reduce shade, but we also found that all the types described were compatible with good ecophysiological development of the cacao trees.Cacao agroforest systems may actually be achieving biodiversity conservation goals in Colombian Amazonia. One challenging prospect will be to monitor and encourage the conservation of tree species diversity in cacao agroforest systems during the development of these cropping systems, as a form of forest-friendly management enhancing sustainable peace building in

  12. Energy Education in Brazil.

    Science.gov (United States)

    Messick, Rosemary; de Paiva, Terezhina Villela O'Grady

    1980-01-01

    Compares energy education in Brazil and the United States. Topics discussed include the Brazilian setting, government initiatives, dependence on foreign fuel sources, public reaction, schools and energy education, and mass media involvement. (DB)

  13. Mutual cooperation with Brazil

    International Nuclear Information System (INIS)

    Orstein, Roberto M.

    1998-01-01

    The history of the nuclear cooperation between Brazil and Argentina is outlined in the framework of the changing political circumstances. Reference is made to the agreements between both countries and to its implementation

  14. IDRC in Brazil

    International Development Research Centre (IDRC) Digital Library (Canada)

    local farmers — particularly women — ... INTERNATIONAL DEVELOPMENT RESEARCH CENTRE. FL. IC ... the roots of violence ... Wage inequalities in Brazil and India ... foreign policy efforts, IDRC supports research in developing countries.

  15. Deforestation in Brazilian Amazonia: The effect of population and land tenure

    International Nuclear Information System (INIS)

    Fearnside, P.M.

    1993-01-01

    LANDSAT data for 1978 and 1988-1991 indicate that by 1991 the area of forest cleared had reached 426 000 km 2 (10.5% of the 4 million km 2 originally forested portion of Brazil's 5 million km 2 Legal Amazon Region). Over the 1978-1988 period, forest was lost at a rate of 22 000 km 2 /yr (including hydroelectric flooding), while the rate was 19 000 km 2 /yr for 1988-1989, 14 000 km 2 /yr for 1989-1990 and 11 000 km 2 /yr for 1990-1991. The reduction in the rate since 1987 has mostly been due to Brazil's economic recession rather than to any policy changes. The number of properties censused in each size class explains 74% of the variation in deforestation rate among the 9 Amazonian states. Multiple regressions indicate that 30% of the clearing in 1991 can be attributed to small farmers (properties <100 ha in area), and the remaining 70% to either medium or large ranchers. The social cost of reducing deforestation rates would therefore be much less than is implied by frequent pronouncements that blame 'poverty' for environmental problems in the region. 46 refs, 4 figs, 5 tabs

  16. Eucalyptus plantations and the steel industry in Amazonia - A contribution from the 3-PG model

    International Nuclear Information System (INIS)

    Behling, Maurel; Piketty, Marie Gabrielle; Morello, Thiago Fonseca; Bouillet, Jean-Pierre; Laclau, Jean-Paul; Mesquita Neto, Franscisco

    2011-01-01

    The Carajas steel industry sector in the Brazilian Amazon has aroused protest on environmental grounds because of its heavy reliance on charcoal. The charcoal is mainly produced from natural forest biomass, with direct and indirect impacts on deforestation and forest ecosystem degradation. Establishing eucalyptus plantations for fuel on degraded pastures could be a workable alternative. Few such plantations exist as yet, and because there are no validated assessments of their production potential, a study was conducted to provide consolidated estimations of the growth and productivity of the Carajas eucalyptus plantations. The estimations were obtained with the 3-PG model (Physiological Principles in Predicting Growth). The model parameters are based on growth data for the eucalyptus plantations established by a company in Breu Branco municipality in Brazil's Para State. Calibrating the model with local data proved to be far more effective than using the parameters set for eucalyptus plantations in other areas in Brazil, South Africa or Australia. The simulations made show that the current annual average growth rate, over a six-year period, of about 20 m"3 per hectare could increase to 30 m"3 with appropriate fertilisation and effective underbrush control. They also suggest that production could be higher without water deficit. Plantation zones shall be selected as a priority in areas where the dry season is the least severe around Carajas. These 3-PG model settings have made it a more effective management tool for industrial plantations in Amazonian conditions. (authors)

  17. A new species of the genus Kingsleya from Amazonia, with a modified key for the Brazilian Pseudothelphusidae (Crustacea: Decapoda: Brachyura)

    NARCIS (Netherlands)

    Magalhaes, C.

    1990-01-01

    Abstract: A new species of Pseudothelphusid crab, Kingsleya besti spec. nov., is described from Serra do Curicuriari, northwest of the State of Amazonas, Brazil. A modified dey for identification of the Pseudothelphusid crabs occurring in Brazil is given. Resumo: É descrita uma nova espécie de

  18. Energy in Brazil

    International Nuclear Information System (INIS)

    Morato de Andrade, C.

    2003-05-01

    To prepare the Gross Domestic Product increase of 4 % in the next years, it is necessary to increase the capacity in Brazil. The government decided actions in favor of the installed capacity growth speeding up and planed investments. This document takes stock on the energy situation in Brazil, the human, political and geographical constraints and the decided measures in favor the energy development. (A.L.B.)

  19. NTFP harvesters as citizen scientists: Validating traditional and crowdsourced knowledge on seed production of Brazil nut trees in the Peruvian Amazon.

    Science.gov (United States)

    Thomas, Evert; Valdivia, Jheyson; Alcázar Caicedo, Carolina; Quaedvlieg, Julia; Wadt, Lucia Helena O; Corvera, Ronald

    2017-01-01

    Understanding the factors that underlie the production of non-timber forest products (NTFPs), as well as regularly monitoring production levels, are key to allow sustainability assessments of NTFP extractive economies. Brazil nut (Bertholletia excelsa, Lecythidaceae) seed harvesting from natural forests is one of the cornerstone NTFP economies in Amazonia. In the Peruvian Amazon it is organized in a concession system. Drawing on seed production estimates of >135,000 individual Brazil nut trees from >400 concessions and ethno-ecological interviews with >80 concession holders, here we aimed to (i) assess the accuracy of seed production estimates by Brazil nut seed harvesters, and (ii) validate their traditional ecological knowledge (TEK) about the variables that influence Brazil nut production. We compared productivity estimates with actual field measurements carried out in the study area and found a positive correlation between them. Furthermore, we compared the relationships between seed production and a number of phenotypic, phytosanitary and environmental variables described in literature with those obtained for the seed production estimates and found high consistency between them, justifying the use of the dataset for validating TEK and innovative hypothesis testing. As expected, nearly all TEK on Brazil nut productivity was corroborated by our data. This is reassuring as Brazil nut concession holders, and NTFP harvesters at large, rely on their knowledge to guide the management of the trees upon which their extractive economies are based. Our findings suggest that productivity estimates of Brazil nut trees and possibly other NTFP-producing species could replace or complement actual measurements, which are very expensive and labour intensive, at least in areas where harvesters have a tradition of collecting NTFPs from the same trees over multiple years or decades. Productivity estimates might even be sourced from harvesters through registers on an annual basis

  20. NTFP harvesters as citizen scientists: Validating traditional and crowdsourced knowledge on seed production of Brazil nut trees in the Peruvian Amazon.

    Directory of Open Access Journals (Sweden)

    Evert Thomas

    Full Text Available Understanding the factors that underlie the production of non-timber forest products (NTFPs, as well as regularly monitoring production levels, are key to allow sustainability assessments of NTFP extractive economies. Brazil nut (Bertholletia excelsa, Lecythidaceae seed harvesting from natural forests is one of the cornerstone NTFP economies in Amazonia. In the Peruvian Amazon it is organized in a concession system. Drawing on seed production estimates of >135,000 individual Brazil nut trees from >400 concessions and ethno-ecological interviews with >80 concession holders, here we aimed to (i assess the accuracy of seed production estimates by Brazil nut seed harvesters, and (ii validate their traditional ecological knowledge (TEK about the variables that influence Brazil nut production. We compared productivity estimates with actual field measurements carried out in the study area and found a positive correlation between them. Furthermore, we compared the relationships between seed production and a number of phenotypic, phytosanitary and environmental variables described in literature with those obtained for the seed production estimates and found high consistency between them, justifying the use of the dataset for validating TEK and innovative hypothesis testing. As expected, nearly all TEK on Brazil nut productivity was corroborated by our data. This is reassuring as Brazil nut concession holders, and NTFP harvesters at large, rely on their knowledge to guide the management of the trees upon which their extractive economies are based. Our findings suggest that productivity estimates of Brazil nut trees and possibly other NTFP-producing species could replace or complement actual measurements, which are very expensive and labour intensive, at least in areas where harvesters have a tradition of collecting NTFPs from the same trees over multiple years or decades. Productivity estimates might even be sourced from harvesters through registers on an

  1. Stratégies territoriales amérindiennes dans un contexte pluri-ethnique : la région de Auaris (Roraima

    Directory of Open Access Journals (Sweden)

    François-Michel Le Tourneau

    2008-06-01

    territory have been recognized as “Indian lands”. But, even if they are considered by some as protected areas (despite a different legal status, the Indian territories are today facing rapid changes, due to the intensifying contact with other sectors of the Brazilian society. One of the main results of those changes is the diminution of the spatial mobility of indigenous villages, influenced by internal (such as changes in the material culture as external factors (such as the federal politics or inter-ethnical relationships.In that context, the case of the region of Auaris, inside the Yanomami territory of Brazil, is of particular interest. It gives a complex example of the changes taking place within Indian lands, and of their geographical consequences. Inhabited by near than 2 200 people, Sanuma and Ye’kuana, it has also seen the installation of several “white” infrastructures, thus showing a great diversity of actors . Furthermore, it seems to undergo a social crisis linked with the diminution of the spatial mobility of the villages. In order to analyse the actual deadlock, we remember in this paper this historical constitution of the Auaris region. We then show what are the strategies of the three main social groups present in the area (the Sanuma, the Ye’kuana, the “Whites”. We finally detail what are the current attempts to bypass the actual difficulties, showing that those are often linked with the fact that traditional solutions are difficult to adapt to the current context.Desde 1988, os direitos territoriais dos Povos Indígenas contidos na nova Constituição brasileira tem sido cumpridos, levando ao reconhecimento de vastas porções de espaço como “terras indígenas”. Mas, embora elas sejam consideradas como Unidades de conservação do meio ambiente por alguns observatores (mesmo que o seu estatuto jurídico seja diferente, essas terras enfrentam hoje rápidas e drásticas mudanças, devidas à aceleração do contato da maioria dos povos

  2. Preliminary Compositional Evidence of Provenance of Ceramics from Hatahara Archaeological Site, Central Amazonia

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    K. P. Nunes

    2013-01-01

    Full Text Available One hundred twenty four ceramic fragments and six clay samples from the Hatahara archaeological site in Amazonas state, Brazil, were analyzed using instrumental neutron activation analysis, INAA, to determine the concentration of twenty chemical elements: Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Nd, Rb, Sc, Ta, Tb, Th, U, Yb, and Zn. The dataset was submitted to multivariate statistical analysis. The classification was done by cluster analysis and discriminant analysis. The results demonstrated the occurrence of four different groups of ceramics, which represent three archaeological phases: Paredão, Manacapuru, and Guarita. This data is consistent with previous traditional petrographic examination of the ceramic samples. Based on probability measures, the great majority of the ceramics are considered to be local in origin.

  3. On Munduruku, a new Theraphosid genus from Oriental Amazonia (Araneae, Mygalomorphae

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    Laura T. Miglio

    2013-06-01

    Full Text Available Munduruku gen. nov. is proposed for the type species Munduruku bicoloratum sp. nov., from Juruti and Santarém, Pará, Brazil. The main diagnostic character of Munduruku gen. nov. is the presence of a subapical, lanceolate keel on the male palpal bulb, which is unique among the basal taxa of Theraphosinae with type III-IV urticating setae. The female spermathecae consist of two spheroid receptacles with funnel-shaped necks, each of which bears a sclerotized area. In both sexes, the abdomen is remarkably patterned, an uncommon feature in adults of New World theraphosids. Both the bulbus lanceolate keel and the abdominal color pattern are hypothesized as synapomorphies of the genus.

  4. Oligarchic forests of economic plants in amazonia: utilization and conservation of an important tropical resource.

    Science.gov (United States)

    Peters, C M; Balick, M J; Kahn, F; Anderson, A B

    1989-12-01

    Tropical forests dominated by only one or two tree species occupy tens of millions of hectares in Ammonia In many cases, the dominant species produce fruits, seeds, or oils of economic importance. Oligarchic (Gr. oligo = few, archic = dominated or ruled by) forests of six economic species, i. e., Euterpe oleracea, Grias peruviana, Jessenia bataua, Mauritia flexuosa, Myrciaria dubia, and Orbignya phalerata, were studied in Brazil and Peru Natural populations of these species contain from 100 to 3,000 conspecific adult trees/ha and produce up to 11.1 metric tons of fruit/hd/yr. These plant populations are utilized and occasionally managed, by rural inhabitants in the region. Periodic fruit harvests, if properly controlled have only a minimal impact on forest structure and function, yet can generate substantial economic returns Market-oriented extraction of the fruits produced by oligarchic forests appears to represent a promising alternative for reconciling the development and conservation of Amazonian forests.

  5. Reactive Case Detection for Plasmodium vivax Malaria Elimination in Rural Amazonia.

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    Pablo S Fontoura

    2016-12-01

    Full Text Available Malaria burden in Brazil has reached its lowest levels in 35 years and Plasmodium vivax now accounts for 84% of cases countrywide. Targeting residual malaria transmission entrenched in the Amazon is the next major challenge for ongoing elimination efforts. Better strategies are urgently needed to address the vast reservoir of asymptomatic P. vivax carriers in this and other areas approaching malaria elimination.We evaluated a reactive case detection (RCD strategy tailored for P. vivax transmission in farming settlements in the Amazon Basin of Brazil. Over six months, 41 cases detected by passive surveillance triggered four rounds of RCD (0, 30, 60, and 180 days after index case enrollment, using microscopy- and quantitative real-time polymerase chain reaction (qPCR-based diagnosis, comprising subjects sharing the household (HH with the index case (n = 163, those living in the 5 nearest HHs within 3 km (n = 878, and individuals from 5 randomly chosen control HHs located > 5 km away from index cases (n = 841. Correlates of infection were identified with mixed-effects logistic regression models. Molecular genotyping was used to infer local parasite transmission networks.Subjects in index and neighbor HHs were significantly more likely to be parasitemic than control HH members, after adjusting for potential confounders, and together harbored > 90% of the P. vivax biomass in study subjects. Clustering patterns were temporally stable. Four rounds of microscopy-based RCD would identify only 49.5% of the infections diagnosed by qPCR, but 76.8% of the total parasite biomass circulating in the proximity of index HHs. However, control HHs accounted for 27.6% of qPCR-positive samples, 92.6% of them from asymptomatic carriers beyond the reach of RCD. Molecular genotyping revealed high P. vivax diversity, consistent with complex transmission networks and multiple sources of infection within clusters, potentially complicating malaria elimination efforts.

  6. Science for the Poor: How One Woman Challenged Researchers, Ranchers, and Loggers in Amazonia

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    Patricia Shanley

    2006-12-01

    Full Text Available In the lower Tocantins region of Brazil, one Amazonian woman questioned why scientists publish principally for elite audiences. Her experience suggests that the impact may be enhanced by also sharing data with people who depend upon forest goods. Having defended her family homestead near the city of Cameta against loggers in the late 1980s, Glória Gaia became interested in strengthening the information base of other villagers so that they would not lose their forests for meager sums. She challenged scientists to defy norms such as extracting data without giving back to rural villagers and publishing primarily for the privileged. Working with researchers, she helped them to publish an illustrated manual of the ecology, economics, management, and cultural importance of key Amazonian forest species. With and without funds or a formal project, she traveled by foot and boat to remote villages to disseminate the book. Using data, stories, and song, she brought cautionary messages to villages about the impacts of logging on livelihoods. She also brought locally useful processing techniques regarding medicinal plants, fruit, and tree oils. Her holistic teachings challenged traditional forestry to include the management of fruits, fibers, and medicines. A new version of the book, requested by the government of Brazil, contains the contributions of 90 leading Brazilian and international scientists and local people. Glória Gaia's story raises the questions: Who is science for and how can science reach disenfranchised populations? Lessons for scientists and practitioners from Glória's story include: broadening the range of products from research to reach local people, complementing local ecological knowledge with scientific data, sharing precautionary data demonstrating trends, and involving women and marginalized people in the research and outreach process.

  7. Neotropics provide insights into the emergence of New World monkeys: New dental evidence from the late Oligocene of Peruvian Amazonia.

    Science.gov (United States)

    Marivaux, Laurent; Adnet, Sylvain; Altamirano-Sierra, Ali J; Boivin, Myriam; Pujos, François; Ramdarshan, Anusha; Salas-Gismondi, Rodolfo; Tejada-Lara, Julia V; Antoine, Pierre-Olivier

    2016-08-01

    Recent field efforts in Peruvian Amazonia (Contamana area, Loreto Department) have resulted in the discovery of a late Oligocene (ca. 26.5 Ma; Chambira Formation) fossil primate-bearing locality (CTA-61). In this paper, we analyze the primate material consisting of two isolated upper molars, the peculiar morphology of which allows us to describe a new medium-sized platyrrhine monkey: Canaanimico amazonensis gen. et sp. nov. In addition to the recent discovery of Perupithecus ucayaliensis, a primitive anthropoid taxon of African affinities from the alleged latest Eocene Santa Rosa locality (Peruvian Amazonia), the discovery of Canaanimico adds to the evidence that primates were well-established in the Amazonian Basin during the Paleogene. Our phylogenetic results based on dental evidence show that none of the early Miocene Patagonian taxa (Homunculus, Carlocebus, Soriacebus, Mazzonicebus, Dolichocebus, Tremacebus, and Chilecebus), the late Oligocene Bolivian Branisella, or the Peruvian Canaanimico, is nested within a crown platyrrhine clade. All these early taxa are closely related and considered here as stem Platyrrhini. Canaanimico is nested within the Patagonian Soriacebinae, and closely related to Soriacebus, thereby extending back the soriacebine lineage to 26.5 Ma. Given the limited dental evidence, it is difficult to assess if Canaanimico was engaged in a form of pitheciine-like seed predation as is observed in Soriacebus and Mazzonicebus, but dental microwear patterns recorded on one upper molar indicate that Canaanimico was possibly a fruit and hard-object eater. If Panamacebus, a recently discovered stem cebine from the early Miocene of Panama, indicates that the crown platyrrhine radiation was already well underway by the earliest Miocene, Canaanimico indicates in turn that the "homunculid" radiation (as a part of the stem radiation) was well underway by the late Oligocene. These new data suggest that the stem radiation likely occurred in the Neotropics

  8. CRECIMIENTO DEL MAÍZ EN VERTISOLES CON ALTO ALUMINIO EN LA BAIXADA MARANHENSE PRE-AMAZONIA, BRASIL

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    Alessandro Costa da Silva

    2014-01-01

    Full Text Available Crecimiento del maíz en vertisoles con alto aluminio en la Baixada Maranhense pre-Amazonia, Brasil. El objetivo de este trabajo fue evaluar el crecimiento del maíz en suelos con alto contenido de aluminio. Se midió el efecto del Al3+ en raíces y la cantidad de materia seca (raíz, hoja y tallo de maíz. Se efectuó la caracterización físico-química de cuatro muestras de suelo con alto aluminio colectadas del horizonte Ap, en tres municipios de la región conocida como Baixada Maranhense (Pre-Amazonia, Brasil: Santa Rita (SR, Arari (AR y Vitoria do Mearim (VM y un testigo colectado en el municipio de São Luís, Área del Núcleo de Tecnología Rural (T. El estudio, ejecutado en 2009, se llevó a cabo en invernadero y se utilizó 2 dm3 de suelo por maceta. Asimismo las muestras fueron divididas en muestras con y sin fertilización. La variación en la longitud de la raíz y de materia seca de las hojas difirió significativamente entre tratados con y sin fertilizante, excepto en la muestra de la localidad T. La producción de materia seca de raíz, tallo y hoja fue mayor en todos los suelos cuando se fertilizó. El suelo testigo también superó a todos los demás en cuanto a producción de materia seca en la raíz, posiblemente como resultado de una menor cantidad de Al3+ (1,2 cmolc/dm3 en comparación con los suelos SR, AR y VM (6,8; 8,0 y 7,0 cmolc/dm3 respectivamente. Se concluye la fertilización reduce el efecto detrimental del aluminio en la producción de maíz en la Baixada Maranhense.

  9. Visceral leishmaniasis in Brazil

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    Mary Marcondes

    2013-10-01

    Full Text Available Visceral leishmaniasis (VL is among the most important vector-borne diseases that occur in Brazil, mainly due to its zoonotic nature. It is currently present in almost all Brazilian territory, and its control is a challenge both for veterinarians and for public health officials. The etiologic agent is Leishmania infantum (syn chagasi, and the main vector in Brazil is Lutzomyia longipalpis. Of all animals identified as reservoirs of VL, the dog is considered the most important domestic reservoir. Although the disease has already been identified in cats, the epidemiological role of this animal species is still unclear. This article presents a brief review of the epidemiological situation of the disease, its mode of transmission, clinical features in dogs and cats as well as possible risk factors associated with the occurrence of the disease in Brazil.

  10. the Energy in Brazil

    International Nuclear Information System (INIS)

    2003-05-01

    To face the forecasted increase of 4 % of the Gross Domestic Product, it is necessary to increase the energy capacity installed in Brazil. The action at first planned on 10 to 20 years, is oriented today on a shorter period from 2001 to 2004. The program proposes investment of 43 milliards or Reals from which 32 will come from the private sector. This report takes stock on the energy situation in Brazil, the human, political and geographical constraints and the actions in favor of the energy development. (A.L.B.)

  11. Scientific integrity in Brazil.

    Science.gov (United States)

    Lins, Liliane; Carvalho, Fernando Martins

    2014-09-01

    This article focuses on scientific integrity and the identification of predisposing factors to scientific misconduct in Brazil. Brazilian scientific production has increased in the last ten years, but the quality of the articles has decreased. Pressure on researchers and students for increasing scientific production may contribute to scientific misconduct. Cases of misconduct in science have been recently denounced in the country. Brazil has important institutions for controlling ethical and safety aspects of human research, but there is a lack of specific offices to investigate suspected cases of misconduct and policies to deal with scientific dishonesty.

  12. Alluvial plain dynamics and human occupation in SW Amazonia during the Holocene: A paleosol-based reconstruction

    Science.gov (United States)

    Lombardo, Umberto; Rodrigues, Leonor; Veit, Heinz

    2018-01-01

    The present study reconstructs Holocene fluvial dynamics in the southern Amazonian foreland basin through the analysis of 36 stratigraphic profiles taken along a 300 km long transect across the Llanos de Moxos (LM), in the Bolivian Amazon. Based on 50 radiocarbon ages from paleosols intercalated with fluvial sediments, the most important changes in floodplain dynamics on a millennial scale are reconstructed and the links between pre-Columbian cultural processes and environmental change in the region explored. Results show that the frequency of river avulsions and crevasses, as inferred from the number and age of the cored paleosols, is stable from 8k cal. yrs BP to 4k cal. yrs BP and increases significantly from 4k to 2k cal. yrs BP, following the strengthening of el Niño/la Niña cycle and an increase in average precipitation. Fluvial activity then decreases and reaches its minimum after 2k cal BP. A comparison between the stratigraphic record and the archaeological record shows a match between periods of landscape stability in SW Amazonia (low river activity) and periods of pre-Columbian human occupation. The first Amazonians lived in the LM until 4k yrs. BP, when an abrupt increase in the frequency of river avulsions and crevasses forced the abandonment of the region. After two thousand years of archaeological hiatus, which matches the period of highest river activity in the region, agriculturists reoccupied the Bolivian Amazon.

  13. A Spatial Probit Econometric Model of Land Change: The Case of Infrastructure Development in Western Amazonia, Peru

    Science.gov (United States)

    Arima, E. Y.

    2016-01-01

    Tropical forests are now at the center stage of climate mitigation policies worldwide given their roles as sources of carbon emissions resulting from deforestation and forest degradation. Although the international community has created mechanisms such as REDD+ to reduce those emissions, developing tropical countries continue to invest in infrastructure development in an effort to spur economic growth. Construction of roads in particular is known to be an important driver of deforestation. This article simulates the impact of road construction on deforestation in Western Amazonia, Peru, and quantifies the amount of carbon emissions associated with projected deforestation. To accomplish this objective, the article adopts a Bayesian probit land change model in which spatial dependencies are defined between regions or groups of pixels instead of between individual pixels, thereby reducing computational requirements. It also compares and contrasts the patterns of deforestation predicted by both spatial and non-spatial probit models. The spatial model replicates complex patterns of deforestation whereas the non-spatial model fails to do so. In terms of policy, both models suggest that road construction will increase deforestation by a modest amount, between 200–300 km2. This translates into aboveground carbon emissions of 1.36 and 1.85 x 106 tons. However, recent introduction of palm oil in the region serves as a cautionary example that the models may be underestimating the impact of roads. PMID:27010739

  14. Diversity and abundance of primates and their threats in the interfluvium of the Napo and Putumayo rivers, Peruvian Amazonia

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    Rolando Aquino

    2016-12-01

    Full Text Available Within the northeastern Peruvian Amazonia remain areas with scarce information on primates, one of them being the interfluvium between the Napo and Putumayo rivers. This lack of information motivated us to conduct a study to determine the diversity and abundance of primates within the area, as well as to identify the threats, which inhibit these primate species populations. For this purpose, we conducted transect censuses in three sampling sites in October 2007, September 2013 and November 2014. In 1040 km of transect walks we observed 308 groups of nine primate species, the most common being Leontocebus nigricollis (109 groups and the rarest being Alouatta seniculus (16 groups. Smaller groups of Lagothrix lagothricha lagothricha (8-11 individuals and A. seniculus (3-5 individuals were observed in Tamboryacu, a majorly disturbed sampling site. Likewise, the lowest population densities estimated for L. l. lagothricha and A. seniculus corresponded to this same sampling site with 3.8 indiv. /km2 and 1.6 indiv. /km2, respectively, while for the remaining species there were no major differences among the sampling sites. Among the activities, hunting and logging are the predominant threats responsible for the scarce populations of A. seniculus and l. l. lagothricha, mainly in the Napo River Basin.

  15. A Spatial Probit Econometric Model of Land Change: The Case of Infrastructure Development in Western Amazonia, Peru.

    Directory of Open Access Journals (Sweden)

    E Y Arima

    Full Text Available Tropical forests are now at the center stage of climate mitigation policies worldwide given their roles as sources of carbon emissions resulting from deforestation and forest degradation. Although the international community has created mechanisms such as REDD+ to reduce those emissions, developing tropical countries continue to invest in infrastructure development in an effort to spur economic growth. Construction of roads in particular is known to be an important driver of deforestation. This article simulates the impact of road construction on deforestation in Western Amazonia, Peru, and quantifies the amount of carbon emissions associated with projected deforestation. To accomplish this objective, the article adopts a Bayesian probit land change model in which spatial dependencies are defined between regions or groups of pixels instead of between individual pixels, thereby reducing computational requirements. It also compares and contrasts the patterns of deforestation predicted by both spatial and non-spatial probit models. The spatial model replicates complex patterns of deforestation whereas the non-spatial model fails to do so. In terms of policy, both models suggest that road construction will increase deforestation by a modest amount, between 200-300 km2. This translates into aboveground carbon emissions of 1.36 and 1.85 x 106 tons. However, recent introduction of palm oil in the region serves as a cautionary example that the models may be underestimating the impact of roads.

  16. Reproducing the organic matter model of anthropogenic dark earth of Amazonia and testing the ecotoxicity of functionalized charcoal compounds

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    Carolina Rodrigues Linhares

    2012-05-01

    Full Text Available The objective of this work was to obtain organic compounds similar to the ones found in the organic matter of anthropogenic dark earth of Amazonia (ADE using a chemical functionalization procedure on activated charcoal, as well as to determine their ecotoxicity. Based on the study of the organic matter from ADE, an organic model was proposed and an attempt to reproduce it was described. Activated charcoal was oxidized with the use of sodium hypochlorite at different concentrations. Nuclear magnetic resonance was performed to verify if the spectra of the obtained products were similar to the ones of humic acids from ADE. The similarity between spectra indicated that the obtained products were polycondensed aromatic structures with carboxyl groups: a soil amendment that can contribute to soil fertility and to its sustainable use. An ecotoxicological test with Daphnia similis was performed on the more soluble fraction (fulvic acids of the produced soil amendment. Aryl chloride was formed during the synthesis of the organic compounds from activated charcoal functionalization and partially removed through a purification process. However, it is probable that some aryl chloride remained in the final product, since the ecotoxicological test indicated that the chemical functionalized soil amendment is moderately toxic.

  17. Territorio y Poder: La reivindicación territorial de los indígenas de la amazonia boliviana

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    Gabriela Canedo Vásquez

    2011-07-01

    Full Text Available El artículo pretende mostrar la centralidad que tiene el territorio y la demanda territorial para los grupos indígenas de la amazonia boliviana. El territorio tiene un papel importante en la reproducción cultural y en la organización política. La investigación se llevó a cabo en la provincia Mojos del departamento del Beni, y muestra que el manejo territorial itinerante y la percepción del territorio que tenían los grupos indígenas se ha transformado a partir del marco estatal –concretamente desde la ley INRA–. Hoy en día los indígenas demandan títulos de propiedad de los espacios ocupados, ante el avasallamiento de los blancos/karayanas. Es así que aquella concepción ilimitada del territorio, propio de los pueblos panindios, se ha transformado, pues en la actualidad los indígenas perciben un territorio limitado, cercado por propiedades privadas. Sin embargo, el territorio al convertirse en una de las demandas centrales de la organización indígena, es el elemento que les permite posicionarse políticamente en un escenario local y nacional.

  18. A Spatial Probit Econometric Model of Land Change: The Case of Infrastructure Development in Western Amazonia, Peru.

    Science.gov (United States)

    Arima, E Y

    2016-01-01

    Tropical forests are now at the center stage of climate mitigation policies worldwide given their roles as sources of carbon emissions resulting from deforestation and forest degradation. Although the international community has created mechanisms such as REDD+ to reduce those emissions, developing tropical countries continue to invest in infrastructure development in an effort to spur economic growth. Construction of roads in particular is known to be an important driver of deforestation. This article simulates the impact of road construction on deforestation in Western Amazonia, Peru, and quantifies the amount of carbon emissions associated with projected deforestation. To accomplish this objective, the article adopts a Bayesian probit land change model in which spatial dependencies are defined between regions or groups of pixels instead of between individual pixels, thereby reducing computational requirements. It also compares and contrasts the patterns of deforestation predicted by both spatial and non-spatial probit models. The spatial model replicates complex patterns of deforestation whereas the non-spatial model fails to do so. In terms of policy, both models suggest that road construction will increase deforestation by a modest amount, between 200-300 km2. This translates into aboveground carbon emissions of 1.36 and 1.85 x 106 tons. However, recent introduction of palm oil in the region serves as a cautionary example that the models may be underestimating the impact of roads.

  19. Fauna de coleópteros aquáticos (insect: coleoptera na Amazônia central, Brasil Aquatic Beetlefauna (insecta: coleoptera in Central Amazonia, Brazil

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    Cesar João Benetti

    2003-12-01

    Full Text Available Foram coletados 888 exemplares de Coleoptera aquáticos nos municípios de Manaus, Manacapuru e Presidente Figueiredo (AM, de fevereiro de 2000 a agosto de 2002, distribuídos em 12 famílias, 50 gêneros e 88 espécies ou morfoespécies. Novas ocorrências para o Brasil, incluem as seguintes espécies de Dytiscidae: Hydrodessus robinae, H. surinamensis, Hypodessus frustrator, Neobidessus confusus, N. spangleri e N. woodruffi. Os gêneros Agaporomorphus (Dytiscidae e Pronoterus (Noteridae são registrados pela primeira vez para o estado do Amazonas, assim como as espécies: P. punctipennis e Suphisellus nigrinus (Noteridae; Agaporomorphus grandisinuatus, Bidessonotus tibialis, Derovatellus lentus,Desmopachria nitida, Hydaticus xanthomelas, Laccophilus tarsalis, Liodessus affinis e Megadytes laevigatus (Dytiscidae. A família Dytiscidae foi a que apresentou maior riqueza, com 34 espécies, seguida de Hydrophilidae, com 20 e Noteridae, com 12 espécies. Os gêneros com maior número de espécies foram Gyretes (Gyrinidae e Suphisellus (Noteridae com 6 espécies, Copelatus (Dytiscidae e Tropisternus (Hydrophilidae, com 5 espécies.In this work, 888 specimens of aquatic Coleoptera were collected in Manaus, Manacapuru and Presidente Figueiredo counties (AM, distributed in 12 families, 50 genera and 88 species or morphospecies. New occurrences in Brasil include the following species of Dytiscidae: Hydrodessus robinae, H. surinamensis, Hypodessus frustrator, Neobidessus confusus, N. spangleri and N. woodruffi. The genera Agaporomorphus (Dytiscidae and Pronoterus (Noteridae were reported for the first time in the State of Amazonas, as well as the species P. punctipennis and Suphisellus nigrinus (Noteridae; Agaporomorphus grandisinuatus, Bidessonotus tibialis, Derovatellus lentus,Desmopachria nitida, Hydaticus xanthomelas, Laccophilus tarsalis, Liodessus affinis and Megadytes laevigatus (Dytiscidae. The family Dytiscidae presented the highest richness, with 34 species, followed by Hydrophilidae, with 20 and Noteridae, with 12 espécies. The genera with greatest number of species were Gyretes (Gyrinidae and Suphisellus (Noteridae with 6 species, Copelatus (Dytiscidae and Tropisternus (Hydrophilidae with 5 species.

  20. Poisonous plants affecting the central nervous system of horses in Brazil

    Science.gov (United States)

    Poisoning by Indigofera pascuori was recently reported in horses in the state of Roraima. It causes chronic signs of sleepiness, unsteady gait, severe ataxia, and progressive weight loss. Some animals are blind. Young horses are more affected than adults. After the end of plant consumption the anima...

  1. Timing of mafic magmatism in the Tapajós Province (Brazil) and implications for the evolution of the Amazon Craton: evidence from baddeleyite and zircon U Pb SHRIMP geochronology

    Science.gov (United States)

    Santos, João Orestes Schneider; Hartmann, Léo Afraneo; McNaughton, Neal Jesse; Fletcher, Ian Robert

    2002-09-01

    The precise timing and possible sources of the mafic rocks in the Amazon craton are critical for reconstruction of the Atlantica supercontinent and correlation of mafic magmatism worldwide. New SHRIMP U-Pb baddeleyite and zircon ages and the reinterpretation of 207 existing dates indicate one orogenic (Ingarana) and four postorogenic (Crepori, Cachoeira Seca, Piranhas, and Periquito) basaltic events in the Tapajós Province, south central Amazon craton. Orogenic gabbro dikes that host gold mineralization are 1893 Ma and interpreted as associated with the Ingarana gabbro intrusions of the bimodal calk-alkalic Parauari intrusive suite. The age of 1893 Ma can be used as a guide to discriminate older and mineralized orogenic dikes from younger and nonmineralized Crepori- and Cachoeira Seca-related mafic dikes. The baddeleyite U-Pb age of the postorogenic Crepori dolerite (gabbro-dolerite sills and dikes) is 1780±9 Ma, ˜150 my older than the ages provided by K-Ar. This value correlates well with the Avanavero tholeiitic intrusions in the Roraima group, in the northern part of the craton in Guyana, Venezuela, and Roraima in Brazil. Early Statherian tholeiitic magmatism was widespread not only in the Amazon craton, but also in the La Plata craton of southern South America, where it is known as the giant Piedra Alta swarm of Uruguay and the post-Trans-Amazonian dikes of Tandil in Argentina. The Cachoeira Seca troctolite represents laccoliths, Feixes, and São Domingos, whose baddeleyite U-Pb age is 1186±12 Ma, 120-150 my older than the known K-Ar ages. This age is comparable to other Stenian gabbroic rocks with alkalic affinity in the craton, such as the Seringa Formation in NE Amazonas and the basaltic flows of the Nova Floresta formation in Rondônia. Dolerite from the giant Piranhas dike swarm in the western Tapajós Province has a Middle Cambrian age (507±4 Ma, baddeleyite) and inherited zircons in the 2238-1229 Ma range. The Piranhas dikes fill extensional NNE and

  2. Subsistence Hunting on a Pioneer Front of Amazonia: Case of Uruará

    Directory of Open Access Journals (Sweden)

    T. Bonaudo

    2001-03-01

    Full Text Available Although prohibited, hunting is widely practiced by rural populations settled along the Transamazon Highway. A diagnostic of subsistence hunting was conducted in 1997 in the Uruará district of Brazil. Beat, hide and trap were the three main hunting techniques, and each one targeted a specific type of game. Although these techniques were rudimentary, 62% of the hunts were successful. Hunters kept their movements within five kilometers at most from their homes, thus covering an 80 km² area. The number of species caught was low: pacas (Agouti paca, deer (Mazama sp. and collared peccaries (Tayassu tajacu provided more than 70% of game meat. The red mazama (Mazama americana, the favorite species, and the paca underwent the highest hunting pressure. In addition to social and ludic roles, hunting had a real nutritional value. Mean daily game meat consumption ranged from 36 to 45.9 g per person (i.e. 13.1–16.7 kg per person per year, depending on the origin of the hunters (urban or rural, respectively. Game hunting did not seem to be the main factor for loss of biodiversity, which might rather result from the transformation of the forest ecosystem into agricultural zones: the habitats were parceled out, generating a reduction in the biodiversity. Community management of wildlife and development of new activities such as breeding of wild animals could help preserve natural resources.

  3. Floristic composition and community structure of epiphytic angiosperms in a terra firme forest in central Amazonia

    Directory of Open Access Journals (Sweden)

    Mariana Victória Irume

    2013-06-01

    Full Text Available This survey aimed to describe the floristic composition and structure of the epiphytic community occurring in a terra firme forest in the city of Coari, Brazil, in the Amazon region. Data collection was performed with a 1.5 ha plot method, with which upland, slope and lowland habitats were sampled. All angiosperm epiphytes and their host plants (diameter at breast height > 10 cm were sampled. We recorded 3.528 individuals in 13 families, 48 genera and 164 species. Araceae was the most prevalent family with regard to the importance value and stood out in all related parameters, followed by Bromeliaceae, Cyclanthaceae and Orchidaceae. The species with the highest epiphytic importance values were Guzmania lingulata (L. Mez. and Philodendron linnaei Kunth. The predominant life form was hemiepiphytic. Estimated floristic diversity was 3.2 (H'. The studied epiphytic community was distributed among 727 host plants belonging to 40 families, 123 genera and 324 species. One individual of Guarea convergens T.D. Penn. was the host with the highest richness and abundance of epiphytes. Stems/trunks of host plants were the most colonized segments, and the most favorable habitat for epiphytism was the lowlands, where 84.1% of species and 48.2% of epiphytic specimens were observed.

  4. Evaluating Water Use for Agricultural Intensification in Southern Amazonia Using the Water Footprint Sustainability Assessment

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    Michael J. Lathuillière

    2018-03-01

    Full Text Available We performed a Water Footprint Sustainability Assessment (WFSA in the Xingu Basin of Mato Grosso (XBMT, Brazil, with the objectives of (1 tracking blue (as surface water and green water (as soil moisture regenerated by precipitation consumption in recent years (2000, 2014; and (2 evaluating agricultural intensification options for future years (2030, 2050 considering the effects of deforestation and climate change on water availability in the basin. The agricultural sector was the largest consumer of water in the basin despite there being almost no irrigation of cropland or pastures. In addition to water use by crops and pasture grass, water consumption attributed to cattle production included evaporation from roughly 9463 ha of small farm reservoirs used to provide drinking water for cattle in 2014. The WFSA showed that while blue and green water consumptive uses were within sustainable limits in 2014, deforestation, cattle confinement, and the use of irrigation to increase cropping frequency could drive water use to unsustainable levels in the future. While land management policies and practices should strive for protection of the remaining natural vegetation, increased agricultural production will require reservoir and irrigation water management to reduce the potential threat of blue water scarcity in the dry season. In addition to providing general guidance for future water allocation decisions in the basin, our study offers an interpretation of blue and green water scarcities with changes in land use and climate in a rapidly evolving agricultural frontier.

  5. PEDO-TRANSFER FUNCTIONS FOR ESTIMATING SOIL BULK DENSITY IN CENTRAL AMAZONIA

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    Henrique Seixas Barros

    2015-04-01

    Full Text Available Under field conditions in the Amazon forest, soil bulk density is difficult to measure. Rigorous methodological criteria must be applied to obtain reliable inventories of C stocks and soil nutrients, making this process expensive and sometimes unfeasible. This study aimed to generate models to estimate soil bulk density based on parameters that can be easily and reliably measured in the field and that are available in many soil-related inventories. Stepwise regression models to predict bulk density were developed using data on soil C content, clay content and pH in water from 140 permanent plots in terra firme (upland forests near Manaus, Amazonas State, Brazil. The model results were interpreted according to the coefficient of determination (R2 and Akaike information criterion (AIC and were validated with a dataset consisting of 125 plots different from those used to generate the models. The model with best performance in estimating soil bulk density under the conditions of this study included clay content and pH in water as independent variables and had R2 = 0.73 and AIC = -250.29. The performance of this model for predicting soil density was compared with that of models from the literature. The results showed that the locally calibrated equation was the most accurate for estimating soil bulk density for upland forests in the Manaus region.

  6. IDRC in Brazil

    International Development Research Centre (IDRC) Digital Library (Canada)

    Subscribe to the IDRC Bulletin: www.idrc.ca/idrcbulletin. BRAZIL. Macapá. Manaus. São Paulo. Belém. Fortaleza. Recife. Salvador. Rio de Janeiro. Porto. Alegre. Brasilia. ✪. ○. ○. ○. ○. ○. ○. ○. ○. ○. BOLIVIA. PERU. ECUADOR. COLOMBIA. VENEZUELA. CHILE. PARAGUAY. Atlantic Ocean. Pacific Ocean.

  7. Adult Education in Brazil.

    Science.gov (United States)

    Ministerio da Educacao e Cultura, Rio de Janeiro (Brazil).

    The status and goals of adult education programs in Brazil are discussed in this report. Supplemental systems such as the Brazilian Literacy Movement (Mobral) and their results are described and evaluated. Charts detailing the evolution of literacy are shown and priorities in education are suggested. The progress of other educational entities is…

  8. Neutron radiography in Brazil

    International Nuclear Information System (INIS)

    Rogers, J.D.

    1983-01-01

    Neutron radiography studies being carried out in reactor centres in Brazil are discussed. These research projects are under way using the 5 MW swimming pool reactor at the Institute of Energy and Nuclear Research (IPEN) in Sao Paulo and the Argonaut reactor at the Institute of Nuclear Engineering (IEN) in Rio de Janeiro. (Auth.)

  9. Brazil: anchoring the region

    International Nuclear Information System (INIS)

    Costamilan, L.C.L.

    1997-01-01

    The role of Brazil's state-run petroleum company, Petrobras, in providing a national supply of oil and natural gas and their products to Brazil was discussed. Petrobras is the sole state-run enterprise which carries out research, exploration, production, refining, imports, exports and the transportation of oil and gas in Brazil. Petrobras has built a complete and modern infrastructure made up of refineries, distribution bases, terminals and oil and gas pipelines. Recently (1995) the Brazilian National Assembly approved legislation that while confirming the state monopoly, also provides private contractors and other state-owned companies ways to participate in the petroleum sector. There exists a great potential for oil and gas in many of Brazil's 29 sedimentary basins. The regulatory legislation also created two new organs to deal with the partial deregulation of the petroleum sector, the National Board for Energy Policy and the National Petroleum Agency. The first of these will deal with policy issues, measures and guidelines regarding regional energy supply and demand and specific programs such as those affecting natural gas, fuel alcohol, coal and nuclear energy. The National Petroleum Agency will manage the hydrocarbon sector on behalf of the government. Its functions will include regulation and monitoring of the sector, managing the bidding process for concessions for exploration and production, and other related activities. The new legislation opens up new horizons for the Brazilian oil sector, providing opportunities for private investment, both domestic and foreign, as well as for new technological capabilities associated with these investments. 1 tab., 6 figs

  10. Diabetes Care in Brazil.

    Science.gov (United States)

    Coutinho, Walmir F; Silva Júnior, Wellington Santana

    2015-01-01

    The diabetes epidemic affects most countries across the world and is increasing at alarming rates in Latin America. Nearly 12 million individuals have diabetes in Brazil, and the current prevalence ranges from 6.3% to 13.5%, depending on the region and the diagnostic criteria adopted in each study. To provide an overview of diabetes care in Brazil, focusing on studies of diabetes epidemiology, prevalence of patients within the standard targets of care, and economic burden of diabetes and its complications. SciELO and PubMed searches were performed for the terms "diabetes," "Brazil," "Brazilian," and "health system"; relevant literature from 1990 to 2015 was selected. Additional articles identified from reference list searches were also included. All articles selected were published in Portuguese and/or English. Recent studies detected a prevalence of gestational diabetes mellitus of nearly 20%. Among patients with type 1 diabetes, almost 90% fail to reach target of glycemic control, with less than 30% receiving treatment for both hypertension and dyslipidemia. More than 75% of patients with type 2 diabetes are either overweight or obese. Most of these patients fail to reach glycemic targets (42.1%) and less than 30% reached the target for systolic and diastolic blood pressure, body mass index, or low-density lipoprotein cholesterol. Only 0.2% of patients reach all these anthropometric and metabolic targets. Brazil is the fourth country in the world in number of patients with diabetes. Regardless of the diabetes type, the majority of patients do not meet other metabolic control goals. The economic burden of diabetes and its complications in Brazil is extremely high, and more effective approaches for preventions and management are urgently needed. Copyright © 2015. Published by Elsevier Inc.

  11. Decay of interspecific avian flock networks along a disturbance gradient in Amazonia

    Science.gov (United States)

    Mokross, Karl; Ryder, Thomas B.; Côrtes, Marina Corrêa; Wolfe, Jared D.; Stouffer, Philip C

    2014-01-01

    Our understanding of how anthropogenic habitat change shapes species interactions is in its infancy. This is in large part because analytical approaches such as network theory have only recently been applied to characterize complex community dynamics. Network models are a powerful tool for quantifying how ecological interactions are affected by habitat modification because they provide metrics that quantify community structure and function. Here, we examine how large-scale habitat alteration has affected ecological interactions among mixed-species flocking birds in Amazonian rainforest. These flocks provide a model system for investigating how habitat heterogeneity influences non-trophic interactions and the subsequent social structure of forest-dependent mixed-species bird flocks. We analyse 21 flock interaction networks throughout a mosaic of primary forest, fragments of varying sizes and secondary forest (SF) at the Biological Dynamics of Forest Fragments Project in central Amazonian Brazil. Habitat type had a strong effect on network structure at the levels of both species and flock. Frequency of associations among species, as summarized by weighted degree, declined with increasing levels of forest fragmentation and SF. At the flock level, clustering coefficients and overall attendance positively correlated with mean vegetation height, indicating a strong effect of habitat structure on flock cohesion and stability. Prior research has shown that trophic interactions are often resilient to large-scale changes in habitat structure because species are ecologically redundant. By contrast, our results suggest that behavioural interactions and the structure of non-trophic networks are highly sensitive to environmental change. Thus, a more nuanced, system-by-system approach may be needed when thinking about the resiliency of ecological networks. PMID:24335983

  12. Protocol for isolation of Moniliophthora roreri (Cif and Par Evans et al. from cacao fruits cv. `National' in the Ecuadorian Amazonia

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    Karina Carrera-Sánchez

    2014-07-01

    Full Text Available Moniliophthora roreri is a pathogen of cocoa (Theobroma cacao L. that causes high economic losses in Ecuador. This paper is intended to present a protocol for the isolation of the pathogen from cocoa fruits cv. `National', showing signs and symptoms of disease. The fruits were collected on farms of Napo (Ecuador. By wet chamber, it was able to induce profusely, sporulation on the surface of selected lesions. The isolations were performed from conidia directly located on the surface of fruits with brown powdery appearance. Isolation procedures and suggested of possible applications are presented.   Key words: amazonia, basidiomycetes, fungi, moniliasis, Theobroma cacao L.

  13. Dental remains of cebid platyrrhines from the earliest late Miocene of Western Amazonia, Peru: Macroevolutionary implications on the extant capuchin and marmoset lineages.

    Science.gov (United States)

    Marivaux, Laurent; Adnet, Sylvain; Altamirano-Sierra, Ali J; Pujos, François; Ramdarshan, Anusha; Salas-Gismondi, Rodolfo; Tejada-Lara, Julia V; Antoine, Pierre-Olivier

    2016-11-01

    Undoubted fossil Cebidae have so far been primarily documented from the late middle Miocene of Colombia, the late Miocene of Brazilian Amazonia, the early Miocene of Peruvian Amazonia, and very recently from the earliest Miocene of Panama. The evolutionary history of cebids is far from being well-documented, with notably a complete blank in the record of callitrichine stem lineages until and after the late middle Miocene (Laventan SALMA). Further documenting their evolutionary history is therefore of primary importance. Recent field efforts in Peruvian Amazonia (Contamana area, Loreto Department) have allowed for the discovery of an early late Miocene (ca. 11 Ma; Mayoan SALMA) fossil primate-bearing locality (CTA-43; Pebas Formation). In this study, we analyze the primate material, which consists of five isolated teeth documenting two distinct Cebidae: Cebus sp., a medium-sized capuchin (Cebinae), and Cebuella sp., a tiny marmoset (Callitrichinae). Although limited, this new fossil material of platyrrhines contributes to documenting the post-Laventan evolutionary history of cebids, and besides testifies to the earliest occurrences of the modern Cebuella and Cebus/Sapajus lineages in the Neotropics. Regarding the evolutionary history of callitrichine marmosets, the discovery of an 11 Ma-old fossil representative of the modern Cebuella pushes back by at least 6 Ma the age of the Mico/Cebuella divergence currently proposed by molecular biologists (i.e., ca. 4.5 Ma). This also extends back to > 11 Ma BP the divergence between Callithrix and the common ancestor (CA) of Mico/Cebuella, as well as the divergence between the CA of marmosets and Callimico (Goeldi's callitrichine). This discovery from Peruvian Amazonia implies a deep evolutionary root of the Cebuella lineage in the northwestern part of South America (the modern western Amazon basin), slightly before the recession of the Pebas mega-wetland system (PMWS), ca. 10.5 Ma, and well-before the subsequent

  14. Estimación de la oferta de frutos en el gradiente vertical de un bosque del medio Caquetá, Amazonia colombiana

    OpenAIRE

    Nicolás Castaño Arbleda; Julio Betancur Betancur

    2004-01-01

    Durante el año 2001 se estimó la oferta de frutos en un bosque de tierra firme de la Amazonia colombiana. Se muestrearon siete parcelas de 50 x 50 m cada una (1,75 ha), en las que se censaron todos los individuos fructificados. En total se encontraron 1.154 individuos en fruto, correspondientes a 196 especies y 57 familias. En cada ciclo de muestreo  se produjeron en promedio 15.212 frutos/ha y 16,1 kg/ha de peso seco de la cosecha. Para estimar la fructificación de cada especie y familia se ...

  15. Secondary organic aerosol formation from ambient air in an oxidation flow reactor in central Amazonia

    Science.gov (United States)

    Palm, Brett B.; de Sá, Suzane S.; Day, Douglas A.; Campuzano-Jost, Pedro; Hu, Weiwei; Seco, Roger; Sjostedt, Steven J.; Park, Jeong-Hoo; Guenther, Alex B.; Kim, Saewung; Brito, Joel; Wurm, Florian; Artaxo, Paulo; Thalman, Ryan; Wang, Jian; Yee, Lindsay D.; Wernis, Rebecca; Isaacman-VanWertz, Gabriel; Goldstein, Allen H.; Liu, Yingjun; Springston, Stephen R.; Souza, Rodrigo; Newburn, Matt K.; Lizabeth Alexander, M.; Martin, Scot T.; Jimenez, Jose L.

    2018-01-01

    Secondary organic aerosol (SOA) formation from ambient air was studied using an oxidation flow reactor (OFR) coupled to an aerosol mass spectrometer (AMS) during both the wet and dry seasons at the Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) field campaign. Measurements were made at two sites downwind of the city of Manaus, Brazil. Ambient air was oxidized in the OFR using variable concentrations of either OH or O3, over ranges from hours to days (O3) or weeks (OH) of equivalent atmospheric aging. The amount of SOA formed in the OFR ranged from 0 to as much as 10 µg m-3, depending on the amount of SOA precursor gases in ambient air. Typically, more SOA was formed during nighttime than daytime, and more from OH than from O3 oxidation. SOA yields of individual organic precursors under OFR conditions were measured by standard addition into ambient air and were confirmed to be consistent with published environmental chamber-derived SOA yields. Positive matrix factorization of organic aerosol (OA) after OH oxidation showed formation of typical oxidized OA factors and a loss of primary OA factors as OH aging increased. After OH oxidation in the OFR, the hygroscopicity of the OA increased with increasing elemental O : C up to O : C ˜ 1.0, and then decreased as O : C increased further. Possible reasons for this decrease are discussed. The measured SOA formation was compared to the amount predicted from the concentrations of measured ambient SOA precursors and their SOA yields. While measured ambient precursors were sufficient to explain the amount of SOA formed from O3, they could only explain 10-50 % of the SOA formed from OH. This is consistent with previous OFR studies, which showed that typically unmeasured semivolatile and intermediate volatility gases (that tend to lack C = C bonds) are present in ambient air and can explain such additional SOA formation. To investigate the sources of the unmeasured SOA-forming gases during this campaign

  16. Visual assessment of soil structure quality in an agroextractivist system in Southeastern Amazonia

    Science.gov (United States)

    Fernanda Simões da Silva, Laura; Stuchi Boschi, Raquel; Ortega Gomes, Matheus; Cooper, Miguel

    2016-04-01

    Soil structure is considered a key factor in the functioning of soil, affecting its ability to support plant and animal life, and moderate environmental quality. Numerous methods are available to evaluate soil structure based on physical, chemical and biological indicators. Among the physical indicators, the attributes most commonly used are soil bulk density, porosity, soil resistance to penetration, tensile strength of aggregates, soil water infiltration, and available water. However, these methods are expensive and generally time costly for sampling and laboratorial procedures. Recently, evaluations using qualitative and semi-quantitative indicators of soil structure quality have gained importance. Among these methods, the method known as Visual Evaluation of Soil Structure (VESS) (Ball et al., 2007; Guimarães et al., 2011) can supply this necessity in temperate and tropical regions. The study area is located in the Piranheira Praialta Agroextrativist Settlement Project in the county of Nova Ipixuna, Pará, Brazil. Two toposequences were chosen, one under native forest and the other under pasture. Pits were opened in different landscape positions (upslope, midslope and downslope) for soil morphological, micromorphological and physical characterization. The use of the soil visual evaluation method (SVE) consisted in collecting an undisturbed soil sample of approximately 25 cm in length, 20 cm in width and 10 cm in depth. 12 soil samples were taken for each land use. The samples were manually fragmented, respecting the fracture planes between the aggregates. The SVE was done comparing the fragmented sample with a visual chart and scores were given to the soil structure. The categories that define the soil structure quality (Qe) vary from 1 to 5. Lower scores mean better soil structure. The final score calculation was done using the classification key of Ball et al. (2007) adapted by Guimarães (2011). A change in soil structure was observed between forest and

  17. Secondary organic aerosol formation from ambient air in an oxidation flow reactor in central Amazonia

    Directory of Open Access Journals (Sweden)

    B. B. Palm

    2018-01-01

    Full Text Available Secondary organic aerosol (SOA formation from ambient air was studied using an oxidation flow reactor (OFR coupled to an aerosol mass spectrometer (AMS during both the wet and dry seasons at the Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5 field campaign. Measurements were made at two sites downwind of the city of Manaus, Brazil. Ambient air was oxidized in the OFR using variable concentrations of either OH or O3, over ranges from hours to days (O3 or weeks (OH of equivalent atmospheric aging. The amount of SOA formed in the OFR ranged from 0 to as much as 10 µg m−3, depending on the amount of SOA precursor gases in ambient air. Typically, more SOA was formed during nighttime than daytime, and more from OH than from O3 oxidation. SOA yields of individual organic precursors under OFR conditions were measured by standard addition into ambient air and were confirmed to be consistent with published environmental chamber-derived SOA yields. Positive matrix factorization of organic aerosol (OA after OH oxidation showed formation of typical oxidized OA factors and a loss of primary OA factors as OH aging increased. After OH oxidation in the OFR, the hygroscopicity of the OA increased with increasing elemental O : C up to O : C ∼ 1.0, and then decreased as O : C increased further. Possible reasons for this decrease are discussed. The measured SOA formation was compared to the amount predicted from the concentrations of measured ambient SOA precursors and their SOA yields. While measured ambient precursors were sufficient to explain the amount of SOA formed from O3, they could only explain 10–50 % of the SOA formed from OH. This is consistent with previous OFR studies, which showed that typically unmeasured semivolatile and intermediate volatility gases (that tend to lack C = C bonds are present in ambient air and can explain such additional SOA formation. To investigate the sources of the

  18. Chagas disease and globalization of the Amazon La enfermedad de Chagas y la globalización de la Amazonia

    Directory of Open Access Journals (Sweden)

    Roberto Briceño-León

    2007-01-01

    Full Text Available The increasing number of autochthonous cases of Chagas disease in the Amazon since the 1970s has led to fear that the disease may become a new public health problem in the region. This transformation in the disease's epidemiological pattern in the Amazon can be explained by environmental and social changes in the last 30 years. The current article draws on the sociological theory of perverse effects to explain these changes as the unwanted result of the shift from the "inward" development model prevailing until the 1970s to the "outward" model that we know as globalization, oriented by industrial forces and international trade. The current article highlights the implementation of five new patterns in agriculture, cattle-raising, mining, lumbering, and urban occupation that have generated changes in the environment and the traditional indigenous habitat and have led to migratory flows, deforestation, sedentary living, the presence of domestic animals, and changes in the habitat that facilitate colonization of human dwellings by vectors and the domestic and work-related transmission of the disease. The expansion of Chagas disease is thus a perverse effect of the globalization process in the Amazon.El incremento de casos autóctonos de la enfermedad de Chagas en la Amazonia a partir de los años setenta hace temer que pueda convertirse en un novedoso problema de salud pública en la región. Este cambio del patrón epidemiológico de la enfermedad en la región amazónica debe ser explicado por las transformaciones ambientales y sociales que han ocurrido en los pasados treinta años. Este artículo utiliza la teoría sociológica de los efectos perversos para explicar esos cambios como el resultado indeseado del cambio de modelo de desarrollo "hacia adentro", que había existido hasta los años setenta, por otro "hacia fuera" que está orientado por las fuerzas de la producción y el comercio internacional que conocemos como globalización. El art

  19. Sequential Management of Commercial Rosewood (Aniba rosaeodora Ducke Plantations in Central Amazonia: Seeking Sustainable Models for Essential Oil Production

    Directory of Open Access Journals (Sweden)

    Pedro Medrado Krainovic

    2017-11-01

    Full Text Available Rosewood (Aniba rosaeodora Ducke is an endangered tree that produces essential oil of high commercial value. However, technical-scientific knowledge about cultivation is scarce and studies are needed to examine the management viability. The current study evaluated rosewood aboveground biomass management, measuring the export of nutrients resulting from harvesting and testing sustainable management models. The crown of 36 rosewood trees were pruned and 108 trees cut at 50 cm above the soil in two regions in Central Amazonia. Post-harvest performance of sprouting shoots was evaluated and after, sprouting shoots were pruned so that the development of two, three and all shoots was permitted. Nutrient stock estimation was calculated as the product of mass and nutrient concentration, which allowed nutritional replacement to be estimated. The pruning facilitates regrowth by 40.11% of the initial mass while by cut regrow 1.45%. Chemical attributes of regrowth biomass differed significantly prior to management and regrowth had a significant correlation with the reserves in root tissues and with the pre -management status of the individual tree. Driving sprouts resulted in significantly larger growth increments and may provide a form of management that can viably be adopted. Biomass sequential management resulted in high nutrient exports and the amount of fertilizer needed for replenishment depended on the intensity and frequency of cropping. Compared with the cut of the tree, pruning the canopy reduces fertilizers that are required to replenish amount by 44%, decreasing to 26.37% in the second rotation. The generated knowledge contributes to this silvicultural practice as it becomes ecologically and economically viable.

  20. Papel trófico del microbial loop en un lago de inundación en la Amazonia Central

    Directory of Open Access Journals (Sweden)

    Pedro Caraballo Gracia

    2012-01-01

    Full Text Available Con el propósito de evaluar la participación de las bacterias heterotróficas en el flujo de carbono en la cadena trófica de un lago de inundación amazónico, colectas mensuales de estos microorganismos fueron realizadas durante el año hidrológico de diciembre de 2007 hasta noviembre de 2008, en las regiones litoral, pelágica y de macrófitas acuáticas del lago Catalão, en la Amazonia Central brasilera. Las bacterias fueron multiplicadas in vitro, usando como sustrato el carbono orgánico disuelto (COD del lago en cada una de las regiones estudiadas, para posterior análisis de la abundancia de isotopos estables de carbono y nitrógeno. Estos datos fueron confrontados con los valores de COD de los cuatro periodos limnológicos del lago (seca, inundación, llena y bajada de aguas. En general se encontró que la fuente principal de carbono de las bacterias heterotróficas fue aquella de origen C4, que presentó un aporte mínimo de 75%, en la medida en que el δ13C de las bacterias presentó valor medio de -17,72‰ ± 2,25. Confrontando ese valor, con el δ13C del zooplancton en el mismo período (-33,04‰±3,81 se concluye que el aporte de las bacterias heterotróficas al flujo de carbono hacia niveles tróficos superiores en el lago estudiado es mínimo.

  1. Determinants of plant community assembly in a mosaic of landscape units in central Amazonia: ecological and phylogenetic perspectives.

    Directory of Open Access Journals (Sweden)

    María Natalia Umaña

    Full Text Available The Amazon harbours one of the richest ecosystems on Earth. Such diversity is likely to be promoted by plant specialization, associated with the occurrence of a mosaic of landscape units. Here, we integrate ecological and phylogenetic data at different spatial scales to assess the importance of habitat specialization in driving compositional and phylogenetic variation across the Amazonian forest. To do so, we evaluated patterns of floristic dissimilarity and phylogenetic turnover, habitat association and phylogenetic structure in three different landscape units occurring in terra firme (Hilly and Terrace and flooded forests (Igapó. We established two 1-ha tree plots in each of these landscape units at the Caparú Biological Station, SW Colombia, and measured edaphic, topographic and light variables. At large spatial scales, terra firme forests exhibited higher levels of species diversity and phylodiversity than flooded forests. These two types of forests showed conspicuous differences in species and phylogenetic composition, suggesting that environmental sorting due to flood is important, and can go beyond the species level. At a local level, landscape units showed floristic divergence, driven both by geographical distance and by edaphic specialization. In terms of phylogenetic structure, Igapó forests showed phylogenetic clustering, whereas Hilly and Terrace forests showed phylogenetic evenness. Within plots, however, local communities did not show any particular trend. Overall, our findings suggest that flooded forests, characterized by stressful environments, impose limits to species occurrence, whereas terra firme forests, more environmentally heterogeneous, are likely to provide a wider range of ecological conditions and therefore to bear higher diversity. Thus, Amazonia should be considered as a mosaic of landscape units, where the strength of habitat association depends upon their environmental properties.

  2. Landscape dynamics in northwestern Amazonia: an assessment of pastures, fire and illicit crops as drivers of tropical deforestation.

    Science.gov (United States)

    Armenteras, Dolors; Rodríguez, Nelly; Retana, Javier

    2013-01-01

    Many studies have identified drivers of deforestation throughout the tropics and, in most cases, have recognised differences in the level of threat. However, only a few have also looked at the temporal and spatial dynamics by which those drivers act, which is critical for assessing the conservation of biodiversity as well as for landscape planning. In this study, we analyse land cover change between 2000 and 2009 in north-western Colombian Amazonia to identify the interactions between the use of fire, cultivation of illicit crops and establishment of pastures, and their impacts on the loss of forest in the region. Yearly analyses were undertaken at randomly selected sample areas to quantify the average areas of transition of land cover types under different landscape compositions: forest-dominated mosaics, pasture mosaics, fire mosaics, and illicit crop mosaics. Our results indicate that despite the fact that forest areas were well-preserved, deforestation occurred at a low annual rate (0.06%). Conversion to pasture was the main factor responsible for forest loss (the area of pastures tripled within forest mosaics over 8 years), and this process was independent of the landscape matrix in which the forests were located. In fire mosaics, burning is a common tool for forest clearing and conversion to pasture. Thus, forests in fire mosaics were highly disturbed and frequently transformed from primary to secondary forests. The use of fire for illicit cropping was not detected, partly due to the small size of common illicit crops. Forest regeneration from pastures and secondary vegetation was observed in areas with large amounts of natural forest. Overall, assuming the continuation of the observed pasture conversion trend and the use of forest fire, we suggest that our results should be incorporated into a spatially explicit and integrated decision support tool to target and focus land-planning activities and policies.

  3. Desmatamento na Amazônia: dinâmica, impactos e controle Deforestation in Amazonia: dynamics, impacts and control

    Directory of Open Access Journals (Sweden)

    Philip M. Fearnside

    2006-01-01

    Full Text Available O desmatamento na Amazônia procede a um alto ritmo por várias razões, muitas das quais dependem de decisões do governo. O desmatamento leva à perda de serviços ambientais, que têm um valor maior que os usos pouco sustentáveis que substituem a floresta. Estes serviços incluem a manutenção da biodiversidade, da ciclagem de água e dos estoques de carbono que evitam o agravamento do efeito estufa. Retroalimentações entre as mudanças climáticas e a floresta, por meio de processos tais como os incêndios florestais, a mortalidade de árvores por seca e calor e a liberação de estoques de carbono no solo, representam ameaças para o clima, a floresta e a população brasileira. Eventos recentes indicam que o desmatamento pode ser controlado, tendo a vontade política, pois os processos subjacentes dependem de decisões humanas.Deforestation in Amazonia proceeds at a rapid rate for various reasons, many of which depend on government decisions. Deforestation causes losses of environmental services that are more valuable than the short-lived uses that replace the forest. These services include maintenance of biodiversity, of water cycling and of the stocks of carbon that avoid further intensification of the greenhouse effect. Feedbacks between climatic changes and the forest through such processes as forest fires, tree mortality from drought and heat and the release of carbon stocks in the soil represent dangers for the climate, the forest and the Brazilian population. Recent events indicate that deforestation can be controlled, given the political will, because the underlying processes depend on human decisions.

  4. Determinants of Plant Community Assembly in a Mosaic of Landscape Units in Central Amazonia: Ecological and Phylogenetic Perspectives

    Science.gov (United States)

    Umaña, María Natalia; Norden, Natalia; Cano, Ángela; Stevenson, Pablo R.

    2012-01-01

    The Amazon harbours one of the richest ecosystems on Earth. Such diversity is likely to be promoted by plant specialization, associated with the occurrence of a mosaic of landscape units. Here, we integrate ecological and phylogenetic data at different spatial scales to assess the importance of habitat specialization in driving compositional and phylogenetic variation across the Amazonian forest. To do so, we evaluated patterns of floristic dissimilarity and phylogenetic turnover, habitat association and phylogenetic structure in three different landscape units occurring in terra firme (Hilly and Terrace) and flooded forests (Igapó). We established two 1-ha tree plots in each of these landscape units at the Caparú Biological Station, SW Colombia, and measured edaphic, topographic and light variables. At large spatial scales, terra firme forests exhibited higher levels of species diversity and phylodiversity than flooded forests. These two types of forests showed conspicuous differences in species and phylogenetic composition, suggesting that environmental sorting due to flood is important, and can go beyond the species level. At a local level, landscape units showed floristic divergence, driven both by geographical distance and by edaphic specialization. In terms of phylogenetic structure, Igapó forests showed phylogenetic clustering, whereas Hilly and Terrace forests showed phylogenetic evenness. Within plots, however, local communities did not show any particular trend. Overall, our findings suggest that flooded forests, characterized by stressful environments, impose limits to species occurrence, whereas terra firme forests, more environmentally heterogeneous, are likely to provide a wider range of ecological conditions and therefore to bear higher diversity. Thus, Amazonia should be considered as a mosaic of landscape units, where the strength of habitat association depends upon their environmental properties. PMID:23028844

  5. Activity budget, diet, and use of space by two groups of squirrel monkeys (Saimiri sciureus) in eastern Amazonia.

    Science.gov (United States)

    Pinheiro, Tatyana; Ferrari, Stephen F; Lopes, Maria Aparecida

    2013-07-01

    Squirrel monkeys (Saimiri spp.) are widely distributed in the Amazon basin. This study describes the ecological and behavioral patterns of two social groups of S. sciureus in forests adjacent to the Tucuruí hydroelectric reservoir in eastern Amazonia, including range size, activity budgets, and composition of the diet. The groups were monitored at Base 4 (group B4) and Germoplasma Island (group GI). Quantitative behavioral data were collected using instantaneous scan sampling to record behavior, substrate use, and height. Home ranges were delimited using a GPS to determine group position after each 50 m of movement. Home ranges were 75.0 ha for group B4 (39 members) and 77.5 ha for group GI (32 members). The use of vertical strata was well defined, with a marked preference for the middle and lower levels of the canopy. The activity budgets of both groups were typical of those of other squirrel monkeys and were dominated by foraging (B4 = 48.7 %; GI = 49.6 %), moving (both groups 28.9 %), and feeding (B4 = 14.6 %; GI = 12.4 %). Resting was rare (B4 = 3.5 %; GI = 2.6 %) and less common than social behavior (B4 = 4.3 %; GI = 6.4 %). The diet of both groups was dominated by plant material (B4 = 70.7 % of feeding records; GI = 71.4 %), which is in contrast with the more insectivorous diets recorded for Saimiri at other sites. Group GI spent more time foraging during the dry season, whereas group B4 spent more time in the rainy season when the consumption of fruit increased (significantly, in the case of group GI). The less insectivorous diet of these groups may be due to a number of factors, including the unique habitat configuration at the site and reduced hydrological stress due to the proximity of the reservoir.

  6. Late Quaternary sedimentary dynamics in Western Amazonia: Implications for the origin of open vegetation/forest contrasts

    Science.gov (United States)

    Rossetti, D. F.; Bertani, T. C.; Zani, H.; Cremon, E. H.; Hayakawa, E. H.

    2012-12-01

    This work investigated the evolution of sedimentary environments during the latest Quaternary and their influence on the paradoxical occurrence of open vegetation patches in sharp contact with the Amazonian forest. The approach integrated pre-existing geological and floristic data from lowlands in the Brazilian Amazonia, with remote sensing imagery including multispectral optical images (TM, ETM+, and ASTER), Phased Array L-band Synthetic Aperture Radar (PALSAR), InSAR C-band SRTM-DEMs, and high resolution images obtained from Google Earth™. The detection of an abundance of paleomorphologies provided evidence of a scenario in which constant environmental shifts were linked to the evolution of fluvial and megafan depositional systems. In all studied areas, the open vegetation patches are not random, but associated with sedimentary deposits representative of environments either deactivated during the Holocene or presently in the process of deactivation. Sedimentary evolution would have determined the distribution of wetlands and terra firme in many areas of the Amazonian lowlands, and would have a major impact on the development of open vegetated patches within the modern rainforest. Subsiding areas were filled up with megafan deposits, and many fluvial tributaries were rearranged on the landscape. The close relationship between vegetation and the physical environment suggests that sedimentary history related to the evolution of depositional settings during the latest Quaternary played a major role in the distribution of flooded and non-flooded areas of the Amazonian lowlands, with a direct impact on the distribution of modern floristic patterns. As the depositional sites were abandoned and their sedimentary deposits were exposed to the surface, they became sites suitable for vegetation growth, first of herbaceous species and then of forest. Although climate fluctuations might have been involved, fault reactivation appears to have been the main cause of changes in

  7. High-resolution mitochondrial DNA analysis sheds light on human diversity, cultural interactions, and population mobility in Northwestern Amazonia.

    Science.gov (United States)

    Arias, Leonardo; Barbieri, Chiara; Barreto, Guillermo; Stoneking, Mark; Pakendorf, Brigitte

    2018-02-01

    Northwestern Amazonia (NWA) is a center of high linguistic and cultural diversity. Several language families and linguistic isolates occur in this region, as well as different subsistence patterns, with some groups being foragers and others agriculturalists. In addition, speakers of Eastern Tukanoan languages are known for practicing linguistic exogamy, a marriage system in which partners are taken from different language groups. In this study, we use high-resolution mitochondrial DNA sequencing to investigate the impact of this linguistic and cultural diversity on the genetic relationships and population structure of NWA groups. We collected saliva samples from individuals representing 40 different NWA ethnolinguistic groups and sequenced 439 complete mitochondrial genomes to an average coverage of 1,030×. The mtDNA data revealed that NWA populations have high genetic diversity with extensive sharing of haplotypes among groups. Moreover, groups who practice linguistic exogamy have higher genetic diversity, while the foraging Nukak have lower genetic diversity. We also find that rivers play a more important role than either geography or language affiliation in structuring the genetic relationships of populations. Contrary to the view of NWA as a pristine area inhabited by small human populations living in isolation, our data support a view of high diversity and contact among different ethnolinguistic groups, with movement along rivers probably facilitating this contact. Additionally, we provide evidence for the impact of cultural practices, such as linguistic exogamy, on patterns of genetic variation. Overall, this study provides new data and insights into a remote and little-studied region of the world. © 2017 Wiley Periodicals, Inc.

  8. Equine influenza in Brazil

    Directory of Open Access Journals (Sweden)

    Patricia Filippsen Favaro

    2016-06-01

    Full Text Available Equine influenza virus (EIV (H3N8 and H7N7 is the causative agent of equine influenza, or equine flu. The H7N7 subtype has been considered to be extinct worldwide since 1980. Affected animals have respiratory symptoms that can be worsened by secondary bacterial respiratory infection, thereby leading to great economic losses in the horse-breeding industry. In Brazil, equine influenza outbreaks were first reported in 1963 and studies on hemagglutination antibodies against viral subtypes in Brazilian horses have been conducted since then. The objective of the present review was to present the history of the emergence of EIV around the world and in Brazil and the studies that have thus far been developed on EIV in Brazilian equines.

  9. IHY activities in Brazil

    Science.gov (United States)

    Dal Lago, Alisson

    The International Heliophysical Year is a program of international scientific colaboration planned to be held in the period from 2007-2009. Many brazilian institutions have shown interest in participating in the IHY activities. All of them provided information about their instrumental facilities and contact person. A list of institutions and their information is shown in the Latin-American IHY webpage (http://www.alage.org/IHYLA/ihyla.html), hosted by the Latin American Association on Space Geophysics - ALAGE. IHY Brazilian activities are being conducted in close colaboration with Latin-American Institutions. Five Coordinated Investigation programs (CIPs) have been proposed by scientists from brazilian institutions. Recentely, in February 2008, there has been the Latin American IHY School in Sao Paulo (Brazil), with the participation of 80 students from Brazil, Argentina, Peru, Mexico and Cuba. In this work, a report on the brazilian activities will be presented.

  10. A new methodology for sampling blackflies for the entomological surveillance of onchocerciasis in Brazil.

    Directory of Open Access Journals (Sweden)

    Érika S do Nascimento-Carvalho

    Full Text Available The effectiveness of the MosqTent® trap was evaluated in endemic area to onchocerciasis in Brazil. This study seeks to provide subsidies for the monitoring of the onchocerciasis transmission in the country. The study was carried out at the Homoxi and Thirei villages, located in the Yanomami Indigenous Land, in the state of Roraima. This area presents hyperendemicity, high blackflies densities, large population migrations and mining activities. The Homoxi and Thirei villages are assisted by the Brazilian Ministry of Health. To conduct the present study, the village leader, health leaders and the Brazilian Ethics Committee were consulted. Blackflies captures were carried out simultaneously at the Homoxi and Thirei, using systematized methods to allow for comparisons between the traditional Human Landing Catch (HLC and HLC protected by the MosqTent®. The female blackflies were captured at two equidistant capture stations per locality, by two collectors per station, for five consecutive days. Individuals captured by interval/station/day were counted, identified and maintained at -20°C. The underlying probability distributions and the differences between the methods for the independent sample data were verified in a comparative statistical analysis between the use of the MosqTent® and the HLC. A total of 10,855 antropophilic blackflies were captured by both methodologies. A total of 7,367 (67.87% blackflies belonging to seven species were captured by MosqTent® -Simulium incrustatum s.l (99.06%; S. guianense s.l (0.74%, S. oyapockense s.l (0.01%, S. exiguum (0.10%, S. metallicum (0.05%, S. ochraceum (0.03% and S. minusculum s.l (0.01%. Moreover, 3,488 (32.14% blackflies belonging to four species were captured by HLC-S. incrustatum s.l (98.33%; S. guianense s.l (1.38%, S. oyapockense s.l (0.26% and S. metallicum (0.03%. The MosqTent® was more effective and efficient when compared to HLC. When comparing total blackflies captured/day, the Mosq

  11. A new methodology for sampling blackflies for the entomological surveillance of onchocerciasis in Brazil.

    Science.gov (United States)

    Nascimento-Carvalho, Érika S do; Cesário, Raquel de Andrade; do Vale, Vladimir Fazito; Aranda, Arion Tulio; Valente, Ana Carolina Dos Santos; Maia-Herzog, Marilza

    2017-01-01

    The effectiveness of the MosqTent® trap was evaluated in endemic area to onchocerciasis in Brazil. This study seeks to provide subsidies for the monitoring of the onchocerciasis transmission in the country. The study was carried out at the Homoxi and Thirei villages, located in the Yanomami Indigenous Land, in the state of Roraima. This area presents hyperendemicity, high blackflies densities, large population migrations and mining activities. The Homoxi and Thirei villages are assisted by the Brazilian Ministry of Health. To conduct the present study, the village leader, health leaders and the Brazilian Ethics Committee were consulted. Blackflies captures were carried out simultaneously at the Homoxi and Thirei, using systematized methods to allow for comparisons between the traditional Human Landing Catch (HLC) and HLC protected by the MosqTent®. The female blackflies were captured at two equidistant capture stations per locality, by two collectors per station, for five consecutive days. Individuals captured by interval/station/day were counted, identified and maintained at -20°C. The underlying probability distributions and the differences between the methods for the independent sample data were verified in a comparative statistical analysis between the use of the MosqTent® and the HLC. A total of 10,855 antropophilic blackflies were captured by both methodologies. A total of 7,367 (67.87%) blackflies belonging to seven species were captured by MosqTent® -Simulium incrustatum s.l (99.06%); S. guianense s.l (0.74%), S. oyapockense s.l (0.01%), S. exiguum (0.10%), S. metallicum (0.05%), S. ochraceum (0.03%) and S. minusculum s.l (0.01%). Moreover, 3,488 (32.14%) blackflies belonging to four species were captured by HLC-S. incrustatum s.l (98.33%); S. guianense s.l (1.38%), S. oyapockense s.l (0.26%) and S. metallicum (0.03%). The MosqTent® was more effective and efficient when compared to HLC. When comparing total blackflies captured/day, the MosqTent® was

  12. Growth of the Cichla temensis Humboldt, 1821 (Perciformes: Cichlidae from the middle rio Negro, Amazonas, Brazil

    Directory of Open Access Journals (Sweden)

    Caroline Pereira Campos

    Full Text Available This study aimed to estimate age and growth of the peacock bass Cichla temensis from the rio Negro (Brazilian Amazonia by analyzing scale annuli. Specimens were captured between October 2011 and September 2012 in the main channel of the river and in adjacent lakes in the municipality of Barcelos, AM, Brazil. Six growth checks were identified on the scales of specimens. The annual variation in body condition observed suggests that fat is accumulated during the dry season. Results for the GSI (gonadosomatic index showed that peak reproduction occurred in the receding-water period, indicating that the fish had energy deficiencies as a result of reproductive activity. RMI (relative marginal increment analysis revealed that an annulus is formed once a year during the receding-water period. The population parameters estimated were L50 (length at sexual maturity = 31.11 cm, L∞ (asymptotic length = 68.05 cm, k (growth coefficient = 0.20.year-1 and A0.95 (longevity = 14 years. Our results corroborate the validity of using growth rings in scales as indicators to estimate the age and growth rate of Cichla temensis in the middle rio Negro.

  13. Schistosomiasis control in Brazil

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    Katz Naftale

    1998-01-01

    Full Text Available In 1975 the Special Programme for Schistosomiasis Control was introduced in Brazil with the objective of controlling this parasitic disease in six northeastern states. The methodology applied varied largely from state to state, but was based mainly on chemotherapy, This Programme was modified about ten years after it beginning with the main goals including control of morbidity and the blockage of establishment of new foci in non-endemic areas. In two states, Bahia and Minas Gerais, the schistosomiasis control programme started in 1979 and 1983, respectively. The recently made evaluation of those two programmes is the main focus of this paper. It must also be pointed out, that the great majority of the studies performed by different researchers in Brazil, at different endemic areas, consistently found significant decrease on prevalence and incidence, when control measures are repeatedly used for several years. Significant decrease of hepatosplenic forms in the studied areas is well documented in Brazil. After more than 20 years of schistosomiasis control programmes in our country, chemotherapy has shown to be a very important tool for the control of morbidity and to decrease prevalence and incidence in endemic areas. Nevertheless, in medium and long terms, sanitation, water supply, sewage draining and health education seem to be the real tools when the aim is persistent and definitive schistosomiasis control.

  14. Allelopathic research in Brazil

    Directory of Open Access Journals (Sweden)

    Manuel Reigosa

    2013-12-01

    Full Text Available In this article, we review allelopathy studies conducted in Brazil or involving plant species that occur in the country. Conceptions and misconceptions associated with allelopathy, as well as some international criteria to be applied in allelopathic research, are presented and discussed. We observed a sharp increase in the number of papers on this subject conducted in Brazil between 1991 and 2010. However, most studies are conducted under laboratory conditions, lack a clear hypothesis or a solid justification, and typically make use of target species that do not co-exist with the donor species under natural conditions. We also found that most studies do not take the additional steps in order to purify and identify the bioactive molecules. We recommend that further studies be conducted in order to explore the potential of plant biodiversity in Brazil. Such studies could lead to the development of new molecular structures (allelochemicals that could be used in the control of pests and weeds, thereby reducing the use of the harmful synthetic herbicides that are currently being widely employed.

  15. Meteorological context of the onset and end of the rainy season in Central Amazonia during the GoAmazon2014/5

    Directory of Open Access Journals (Sweden)

    J. A. Marengo

    2017-06-01

    Full Text Available The onset and demise of the rainy season in Amazonia are assessed in this study using meteorological data from the GoAmazon experiment, with a focus on the 2014–2015 rainy season. In addition, global reanalyses are also used to identify changes in circulation leading to the establishment of the rainy season in the region. Our results show that the onset occurred in January 2015, 2–3 pentads later than normal, and the rainy season during the austral summer of 2015 contained several periods with consecutive dry days in both Manacapuru and Manaus, which are not common for the wet season, and resulted in below-normal precipitation. The onset of the rainy season has been strongly associated with changes in large-scale weather conditions in the region due to the effect of the Madden–Julian Oscillation (MJO. Regional thermodynamic indices and the height of the boundary layer did not present a significant difference between the onset and demise of the wet season of 2015. This suggests that local changes, such as those in the regional thermodynamic characteristics, may not have influenced its onset. Thus, variability of the large-scale circulation was responsible for regional convection and rainfall changes in Amazonia during the austral summer of 2014–2015.

  16. Aspectos agronómicos sobre el cultivo del arazá (eugenia stipitata me vaugh Frutal promisorio de la amazonia colombiana

    Directory of Open Access Journals (Sweden)

    Quevedo Garcia Enrique

    1995-06-01

    Full Text Available

    En este trabajo se presenta un estudio del manejo agronómico del cultivo del arazá (Eugenia slipitata Mc. Vaugh en la Amazonia colombiana y una revisión del manejo del arazá en la Amazonia del Brasil y Perú. Se concluye que esta es una especie en vía de domesticación que puede ser cultivada en otras regiones de Colombia y que podría ser un sustituto para los cultivos ilícitos. Si somos hábiles en logra establecer el cultivo del arazá. En reglones con características ecológicas adecuadas para esta especie en corto tiempo, obtendremos un fruto para el consumo humano y su usa extensivo en Colombia.

  17. Abundancia de actinomicetes y micorrizas arbusculares en paisajes fragmentados de la Amazonia colombiana

    Directory of Open Access Journals (Sweden)

    Cardona Gladys I. Cardona

    2005-12-01

    ="Subtle Emphasis" />

    Se evalúo la abundancia de actinomicetes y hongos Micorriza Arbuscular (MA en suelos bajo coberturas de bosque y pasto, en una zona de colonización de la Amazonia colombiana con tres grados de transformación antrópica. Se realizó una estratificación espacial de la fragmentación del paisaje de tierra firme, en cercanías de San Jos

  18. Development of floristic diversity in 10-year-old restoration forests on a bauxite mined site in Amazonia.

    Science.gov (United States)

    J. A. Parrotta; O. H. Knowles; J.M. Wunderle Jr.

    1997-01-01

    Patterns of plant and animal diversity were studied in a 10-year-old native species reforestation area at a bauxite-mined site at porto Trombetas in western Para State, Brazil. Understorey and overstorey floristic composition and structure, understorey light conditions, forest floor development and soil properties were evaluated in a total of 38 78.5-m2

  19. Field and geochemical constraints on the relationship between the Apoteri basalts (northern Brazil, southwestern Guyana) and the Central Atlantic Magmatic Province

    Science.gov (United States)

    Pinto, Viter M.; Santos, João Orestes S.; Ronchi, Luiz H.; Hartmann, Léo A.; Bicudo, Carlos Alberto; de Souza, Vladimir

    2017-11-01

    In northern Brazil, Roraima state and southwestern Guyana, basalt flows characterized by inflated pahoehoe structure occur along the margins of the Tacutu Rift Valley, dykes intrude the Paleoproterozoic basement close to the boundary of the rift system with concordant, NE-trend. The dykes and flows belong to Apoteri magmatism. New field, geochemical data (major, trace and rare-earth elements) and chemical stratigraphy of the Apoteri magmatism indicate petrographic and chemical homogeneity characteristic of continental tholeiitic basalts. The basalt flows of Morro Redondo and Nova Olinda sites show two distinct chemical groups: a) the lower flows with intermediate TiO2 content (ITi group) ranging from 1.09 to 1.41 wt%, MgO (5.64-6.46 wt%) and Ni (43-53 ppm) contents; and b) the upper flows with lower TiO2 content (LTi group) = 0.75 to 0.78 wt%, higher MgO = 7.95-8.85 wt% and Ni = 105-115 ppm. The two magma types share many characteristics in high field strength elements (HFSE) and rare earth elements (REE), but in detail significant differences exist in REE ratios, e.g. (La/Yb)N of ∼4.0 for ITi and 3.2 for LTi and this may be explained by fractional crystallization. The chemical compositions of the Apoteri dykes are similar the ITi group analyses, suggesting that they have the same origin. The La/Ba versus La/Nb diagram is indicative of large ion lithophile elements (LILE) enrichment and LILE/HFSE fractionation in the mantle source, and the data favor a dominant subcontinental lithospheric mantle (SCLM) component in the origin of the Apoteri flows and dykes. These data show consistent similar chemical characteristics and correspond to other tholeiitic flows from the large Central Atlantic Magmatic Province (CAMP), especially eastern USA.

  20. Restoration practicesin Brazil's Atlantic rainforest.

    Science.gov (United States)

    Jorge Correa de Lima Palidon; Maisa dos Santos Guapyassu

    2005-01-01

    The atlantic Rain Forst (Mata Atlantica) extends along the southern coast of Brazil and inland into Argentina and Paraguay. Originally covering 15% of the land area of Brazil, it was a region of an estimated 1.3 million km2 (MMA 2000). Today, remnants of the Atlantic Forest represents about 8% of the original area, or some 94,000 km2...

  1. Nuclear material control in Brazil

    International Nuclear Information System (INIS)

    Marzo, M.A.S.; Iskin, M.C.L.; Palhares, L.C.; Almeida, S.G. de.

    1988-01-01

    A general view about the safeguards activities in Brazil is presented. The national system of accounting for and control of nuclear materials is described. The safeguards agreements signed by Brazil are presented, the facilities and nuclear material under these agreements are listed, and the dificulties on the pratical implementation are discussed. (E.G.) [pt

  2. LDC nuclear power: Brazil

    International Nuclear Information System (INIS)

    Johnson, V.

    1982-01-01

    Brazil has been expanding its nuclear power since 1975, following the Bonn-Brasilia sales agreement and the 1974 denial of US enriched uranium, in an effort to develop an energy mix that will reduce dependence and vulnerability to a single energy source or supplier. An overview of the nuclear program goes on to describe domestic non-nuclear alternatives, none of which has an adequate base. The country's need for transfers of capital, technology, and raw materials raises questions about the advisability of an aggressive nuclear program in pursuit of great power status. 33 references

  3. Social Psychotherapy in Brazil.

    Science.gov (United States)

    Fleury, Heloisa J; Marra, Marlene M; Knobel, Anna M

    2015-10-01

    This paper describes the practice of sociodrama, a method created by J. L. Moreno in the 1930s, and the Brazilian contemporary socio-psychodrama. In 1970, after the Fifth International Congress of Psychodrama was held in Brazil, group psychotherapy began to flourish both in private practice and hospital clinical settings. Twenty years later, the Brazilian health care system added group work as a reimbursable mental health procedure to improve social health policies. In this context, socio-psychodrama became a key resource for social health promotion within groups. Some specific conceptual contributions by Brazilians on sociodrama are also noteworthy.

  4. Crecimiento del maíz en vertisoles con alto aluminio en la Baixada Maranhense pre-Amazonia, Brasil.

    Directory of Open Access Journals (Sweden)

    Alessandro Costa-da Silva

    2014-07-01

    Full Text Available El objetivo de este trabajo fue evaluar el crecimiento del maíz en suelos con alto contenido de aluminio. Se midió el efecto del Al3+ en raíces y la cantidad de materia seca (raíz, hoja y tallo de maíz. Se efectuó la caracterización físico-química de cuatro muestras de suelo con alto aluminio colectadas del horizonte Ap, en tres municipios de la región conocida como Baixada Maranhense (Pre-Amazonia, Brasil: Santa Rita (SR, Arari (AR y Vitoria do Mearim (VM y un testigo colectado en el municipio de São Luís, Área del Núcleo de Tecnología Rural (T. El estudio, ejecutado en 2009, se llevó a cabo en invernadero y se utilizó 2 dm3 de suelo por maceta. Asimismo las muestras fueron divididas en muestras con y sin fertilización. La variación en la longitud de la raíz y de materia seca de las hojas difirió significativamente entre tratados con y sin fertilizante, excepto en la muestra de la localidad T. La producción de materia seca de raíz, tallo y hoja fue mayor en todos los suelos cuando se fertilizó. El suelo testigo también superó a todos los demás en cuanto a producción de materia seca en la raíz, posiblemente como resultado de una menor cantidad de Al3+ (1,2 cmolc/dm3 en comparación con los suelos SR, AR y VM (6,8; 8,0 y 7,0 cmolc/dm3 respectivamente. Se concluye la fertilización reduce el efecto detrimental del aluminio en la producción de maíz en la Baixada Maranhense.

  5. Treating leishmaniasis in Amazonia: A review of ethnomedicinal concepts and pharmaco-chemical analysis of traditional treatments to inspire modern phytotherapies.

    Science.gov (United States)

    Odonne, Guillaume; Houël, Emeline; Bourdy, Geneviève; Stien, Didier

    2017-03-06

    Cutaneous and mucocutaneous leishmaniasis are neglected tropical diseases that occur in all intertropical regions of the world. Amazonian populations have developed an abundant knowledge of the disease and its remedies. Therefore, we undertook to review traditional antileishmanial plants in Amazonia and have developed new tools to analyze this somewhat dispersed information. A literature review of traditional remedies for cutaneous/mucocutaneous leishmaniasis in the Amazon was conducted and the data obtained was used to calculate distribution indexes designed to highlight the most relevant uses in Amazonia. The cultural distribution index represents the distribution rate of a given taxon among different cultural groups and was calculated as the ratio of the number of groups using the taxon to the total number of groups cited. The geographical distribution index allowed us to quantify spatial distribution of a taxon's uses in Amazonia and was calculated geometrically by measuring the average distance between the points where uses have been reported and the barycenter of those points. The general distribution index was defined as an arithmetic combination of the previous two and provides information on both cultural and spatial criteria. 475 use reports, concerning 291 botanical species belonging to 83 families have been gathered depicted from 29 sources. Uses concern 34 cultural groups. While the use of some taxa appears to be Pan-Amazonian, some others are clearly restricted to small geographical regions. Particular attention has been paid to the recipes and beliefs surrounding treatments. Topical application of the remedies dominated the other means of administration and this deserves particular attention as the main treatments against Neotropical leishmaniasis are painful systemic injections. The data set was analyzed using the previously defined distribution indexes and the most relevant taxa were further discussed from a phytochemical and pharmacological point

  6. Heparin pharmacovigilance in Brazil.

    Science.gov (United States)

    Junqueira, Daniela Rezende Garcia; Viana, Thércia Guedes; Peixoto, Eliane R de M; Barros, Fabiana C R de; Carvalho, Maria das Graças; Perini, Edson

    2011-01-01

    To investigate the biological origin of injectable unfractioned heparin available in Brazilian market by discussing the impact of the profile of commercial products and the changes in heparin monograph on the drug safety. The Anvisa data base for the Registered Products of Pharmaceutical Companies and the Dictionary of Pharmaceutical Specialties (DEF 2008/2009) were searched. A survey with industries having an active permission for marketing the drug in Brazil was conducted. Five companies were granted a permission to market unfractioned heparin in Brazil. Three of them are porcine in origin and two of them are bovine in origin, with only one explicitly showing this information in the package insert. The effectiveness and safety of heparin studied in non-Brazilian populations may not represent the Brazilian reality, since most countries no longer produce bovine heparin. The currently marketed heparin has approximately 10% less anticoagulant activity than that previously produced and this change may have clinical implications. Evidence about the lack of dose interchangeability between bovine and porcine heparins and the unique safety profile of these drugs indicates the need to follow the treatment and the patients' response. Events threatening the patient's safety must be reported to the pharmacovigilance system in each particular country.

  7. Fuelwood utilization in Brazil

    International Nuclear Information System (INIS)

    Brito, J.O.

    1997-01-01

    The annual consumption of fuelwood in Brazil is approximately equal to 180 million oil barrels, or 13.3% of all Brazilian primary energy use. Fuelwood consumption in the country is greater than the use of wood for industrial use. Fuelwood taken from existing forest has been a very common activity in Brazil. Forest plantations to support the Brazilian fuelwood consumption have not been important. As fuelwood consumption in the country is expected to increase in the future, it is important to increase the supply of wood by sustainable use of the existing natural forests. Even if they are far from the centers of consumption, these are only available reserves capable of supporting the Brazilian future fuelwood requirements. For this reason it is necessary to use advanced technology to convert the energy of wood efficiently into a form (such as electricity) to carry it to the centers of consumption. In addition, forest plantations would be established in the available areas, mainly for specific uses, as for charcoal production for the pig-iron and steel industries. In all the above plans, at least, the US3/2 billion/year that represents the current Brazilian fuelwood consumption should be returned to rehabilitate the forest growing stock. In addition, it would be used to stimulate the development and use of the most suitable systems of fuelwood conversion, improving the efficiency of energy production. (author)

  8. Logging Activity in the Trinational Amazonian Region of Pando/Bolivia, Acre and Rond“nia/Brazil, and Madre de Dios/Peru: Analysis of Existing Data

    Science.gov (United States)

    Mendoza, E.; Brilhante, S. H.; Brown, I.; Peralta, R.; Rivero, S.; Melendez, N.

    2002-12-01

    Logging activity in the trinational southwestern Amazonia will grow in importance as a driver of regional land-use change as expanding road access facilitates both timber extraction and transport to international markets. Official data on current activity in this ~50 million ha region are limited and inconsistent with differences as much as twenty-fold between official estimates; nevertheless, they serve as guides for understanding the relative magnitude of logging activities. For 2000, an estimated 5 million m3 of timber were commercialized in Rondonia, 400,000 m3 in Acre, Brazil, and 200,000 m3 for the combined departments of Pando, Bolivia and Madre de Dios, Peru. About 70% of this timber originates from clear cutting done for pasture and agriculture activities, nearly a third from unregulated selective logging, and only 2% from managed selective logging. Eight timber species are preferentially extracted. The total area for timber concessions in Acre, Pando and Madre de Dios extends to about 4 million ha for a potential timber supply of 65 million m3. About 150,000 m3/yr of illegal timber is confiscated by federal and state agencies in Acre, Pando and Madre de Dios. Problems of enforcement in the region are due principally to the lack of trained personnel and little cooperation among agencies of the three countries. Proposed development plans indicate a 3- to >10-fold increase in logging activity in the Acre and Pando regions during the coming decade. More detailed studies are urgently needed to guide sustainable development of this resource in southwestern Amazonia.

  9. Opening up Brazil's hydrocarbon sector - the Bolivia-Brazil pipeline

    International Nuclear Information System (INIS)

    Law, P.

    2000-01-01

    The Bolivia-Brazil natural gas pipeline, which transports natural gas more than 3000 km from Bolivia to Brazil, cost US$2.1 billion to construct. Despite the substantial benefits for both Bolivia and Brazil and the involvement of reputable private partners, the perceived risks and complexities of this large project made financing it major challenge. neither of these countries has had a tradition of independent regulation or economic fuel pricing, and the pipeline was the first major gas infrastructure project involving the private sector in Brazil. The presentation explains the historical features of the project and how the project was used to open up Brazilian oil and gas sector to private investment and competition. (author)

  10. Notes on the insect fauna on two species of astrocaryum (palmae, cocoeae, bactridinae in peruvian amazonia, with emphasis on potential pests of cultivated palms

    Directory of Open Access Journals (Sweden)

    1992-01-01

    Full Text Available NOTES SUR LA FAUNE ENTOMOLOGIQUE DE DEUX ESPÈCES D'ASTROCARYUM (PALMAE, COCOEAE, BACTRIDINAE DE L'AMAZONIE PÉRUVIENNE, ET MISE EN ÉVIDENCE DE RAVAGEURS POTENTIELS DES PALMIERS CULTIVÉS. La faune entomologique des palmiers Astrocaryum chanta et Astrocaryum carnosum a été étudiée dans deux sites différents de l'Amazonie péruvienne : région de Jenaro Herrera sur le bas Ucayali pour la première espèce, et région d'Uchiza sur le haut Huallaga pour la seconde. Cette faune est extrêmement diversifiée. Elle comprend de nombreuses espèces d'insectes connues comme ravageurs des palmiers cultivés, ainsi que d'autres espèces de phytophages dont les plantes hôtes n'étaient pas encore connues. De nombreuses autres espèces d'insectes, prédateurs ou de niveau trophique mal défini, font aussi partie de la biocénose des palmiers étudiés. Astrocaryum chanta et Astrocaryum carnosum sont considérés comme foyers d'infestation en ravageurs pour les plantations industrielles de palmiers en Amazonie péruvienne. NOTAS SOBRE LA FAUNA DE INSECTOS DE DOS ESPECIES DE ASTROCARYUM (PALMAE, COCOEAE, BACTRIDINAE EN LA AMAZONIA PERUANA, CON ÉNFASIS EN LAS PLAGAS POTENCIALES DE LAS PALMERAS CULTIVADAS. La fauna de insectos de las palmas Astrocaryum chonta y Astrocaryum carnosum se ha estudiado en dos lugares diferentes de la Amazonia peruana: en la región de Jenaro Herrera, bajo Ucayali para la primera especie, y en la región de Uchiza, alto Huallaga para la segunda. Esta fauna es extremadamente diversificada. Incluye numerosas especies de insectos conocidos como depredadores de las palmas cultivadas, así como otras especies de fitófagos cuyas plantas hospedantes aún no eran conocidas. Numerosas especies de otros insectos, depredadores o de un nivel trófico mal definido, forman parte también de la biocenosis de las palmas estudiadas. Astrocaryum chonta y Astrocaryum carnosum son considerados como focos de infestación de depredadores para las

  11. VILLAGE’S HERDS: INVESTIGATING THE INTRODUCTION OF DOMESTIC ANIMALS AND PATTERNS OF ANIMAL HUSBANDRY AMONG INDIGENOUS PEOPLES IN AMAZONIA (RONDÔNIA

    Directory of Open Access Journals (Sweden)

    Felipe Ferreira Vander Velden

    2011-06-01

    Full Text Available This paper discuss the introduction of European domestic animals in indigenous villages in the Amazon, with particular stress on groups in Rondonia, specially the Karitiana, a Tupi-Arikém-speaking people that lives in the north of that state. In what concerns the history of Brazilian territorial conquest, marked by the ‘frentes pastoris’’ great narrative, and the present expansion – material and also ideological – of husbandry throughout Amazonia, this article points to many questions about the position of these animals – above all cattle – in indigenous peoples’ symbolical and material universes. Suggests new investigative possibilities, that inquires not only implemented experiences with animal husbandry in indigenous villages, but also desires and projects designed to future implementations.

  12. The history of the introduction of the giant river prawn, Macrobrachium cf. rosenbergii (Decapoda, Palaemonidae, in Brazil: new insights from molecular data

    Directory of Open Access Journals (Sweden)

    Gabriel Iketani

    2011-01-01

    Full Text Available The giant river prawn, Macrobrachium cf. rosenbergii, is one of the most cultivated freshwater prawns in the world and has