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Sample records for eastern amazonian brazil

  1. Population structure of the malaria vector Anopheles darlingi in a malaria-endemic region of Eastern Amazonian Brazil

    DEFF Research Database (Denmark)

    Conn, Jan E.; Vineis, Joseph H.; Bollback, Jonathan Paul;

    2006-01-01

    Anopheles darlingi is the primary malaria vector in Latin America, and is especially important in Amazonian is the primary malaria vector in Latin America, and is especially important in Amazonian Brazil. Historically, control efforts have been focused on indoor house spraying using a variety...... malaria epidemic. In contrast, although An. darlingi was eradicated from some districts of the city of Belem (the capital of Para State) in 1968 to reduce malaria, populations around the water protection area in the eastern district were treated only briefly. To investigate the population structure of An...

  2. Effects of water and nutrient availability on fine root growth in eastern Amazonian forest regrowth, Brazil.

    Science.gov (United States)

    Lima, Tâmara Thaiz Santana; Miranda, Izildinha Souza; Vasconcelos, Steel Silva

    2010-08-01

    *Fine root dynamics is widely recognized as an important biogeochemical process, but there are few data on fine root growth and its response to soil resource availability, especially for tropical forests. *We evaluated the response of fine root dynamics to altered availability of soil water and nutrients in a 20-yr-old forest regrowth in eastern Amazonia. In one experiment the dry season reduction in soil moisture was alleviated by irrigation. In the other experiment, nutrient supply was reduced by litter removal. We used the ingrowth core technique to measure fine root mass growth, length growth, mortality and specific root length. *Dry-season irrigation had no significant effect on mass and length of live and dead roots, whereas litter removal reduced mass and length of live roots. For both irrigation and litter removal experiments, root growth was significantly greater in the dry season than in the wet season. *Increased root growth was associated with decreased soil water availability. However, root growth did not increase in response to nutrient reduction in litter removal plots. Overall, our results suggest that belowground allocation may differ according to the type of soil resource limitation.

  3. Brazil's Amazonian dams: Ecological and socioeconomic impacts

    Science.gov (United States)

    Fearnside, P. M.

    2016-12-01

    Brazil's 2015-2024 Energy Expansion Plan calls for 11 hydroelectric dams with installed capacity ≥ 30 MW in the country's Amazon region. Dozens of other large dams are planned beyond this time horizon, and dams with consumers. Population displacement is a major impact; for example, the Marabá Dam would displace 40,000 people, mostly traditional riverside dwellers (ribeirinhos). Various dams impact indigenous peoples, such as the Xingu River dams (beginning with Belo Monte) and the São Luiz do Tapajós and Chacorão Dams on the Tapajós River. Brazil has many energy options other than dams. Much energy use has little benefit for the country, such as exporting aluminum. Electric showerheads use 5% of the country's power. Losses in transmission lines (20%) are far above global averages and can be expected to increase as Amazonian hydroelectric dams far from consumer centers come on line. Brazil has tremendous wind and solar potential, but these do not have the same priority as dams. At the root of many questionable policies is a decision-making process in need of reform.

  4. Pterygium: prevalence and severity in an Amazonian ophthalmic setting, Brazil

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    Sophie Joanna Coutts

    2012-12-01

    Full Text Available OBJECTIVE: This is a cross sectional ophthalmic clinic-based study to estimate the prevalence and severity of pterygium in a selected population in the Amazon Basin, Brazil. METHODS: The study included 225 subjects above 20 years age from three different places of residence of Manaus city (group 1, n=89, river based communities (group 2, n= 116 and indigenous rainforest inhabitants (group 3, n=20. Pterygia was graded 1-4 by torch examination and gender, age and occupation determined. RESULTS: were assessed to have pterygia (grades 2-4 117 people; 52% against 108 control subjects with bilateral disease in 43% of subjects. Prevalence of grades 2-4 increased from 36% in group 1 to 62.5 % in group 2 and 75% in group 3. Of these subjects the percentage with outdoor professions increased across the groups from 31.2% to 67.1 % and 70% respectively. Also subjects of group 2 who worked largely outdoors, showed increasing pterygia severity, from grades 2 at 57% (p=0.0002, grade 3 at 93.3% (p,0.0001 to grade 4 at 100% (p=0.0004 CONCLUSION: Amazonian communities have a high prevalence of pterygia, which correlates to greater outdoor occupation and sun exposure. This study agrees with previous worldwide reports and it is the first study to compare the prevalence of pterygium in rural and urban living in Amazonian in Brazil. This study highlights the public health significance and gross need for intervention studies.

  5. Mosquitoes of eastern Amazonian Ecuador: biodiversity, bionomics and barcodes

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    Yvonne-Marie Linton

    2013-01-01

    Full Text Available Two snapshot surveys to establish the diversity and ecological preferences of mosquitoes (Diptera: Culicidae in the terra firme primary rain forest surrounding the Tiputini Biodiversity Station in the UNESCO Yasuní Biosphere Reserve of eastern Amazonian Ecuador were carried out in November 1998 and May 1999. The mosquito fauna of this region is poorly known; the focus of this study was to obtain high quality link-reared specimens that could be used to unequivocally confirm species level diversity through integrated systematic study of all life stages and DNA sequences. A total of 2,284 specimens were preserved; 1,671 specimens were link-reared with associated immature exuviae, all but 108 of which are slide mounted. This study identified 68 unique taxa belonging to 17 genera and 27 subgenera. Of these, 12 are new to science and 37 comprise new country records. DNA barcodes [658-bp of the mtDNA cytochrome c oxidase ( COI I gene] are presented for 58 individuals representing 20 species and nine genera. DNA barcoding proved useful in uncovering and confirming new species and we advocate an integrated systematics approach to biodiversity studies in future. Associated bionomics of all species collected are discussed. An updated systematic checklist of the mosquitoes of Ecuador (n = 179 is presented for the first time in 60 years.

  6. Amazonian dark earths and Caboclo subsistence on the middle Madeira River, Brazil

    OpenAIRE

    Fraser, James Angus

    2010-01-01

    This thesis examines the relationship between Amazonian Dark Earths (ADE) and Caboclo subsistence on the Middle Madeira River, Brazil. ADE are fertile anthropogenic (man-made) soils formed through practices of burning and waste disposal by pre-Columbian Amerindian populations. “Caboclo” is a social category that refers to the people of diverse origins that form the majority of the contemporary rural population of Brazilian Amazonia. Bitter manioc fields (roças) and homegardens (sítios) are th...

  7. Soil moisture dynamics in an eastern Amazonian tropical forest

    Science.gov (United States)

    Bruno, Rogério D.; da Rocha, Humberto R.; de Freitas, Helber C.; Goulden, Michael L.; Miller, Scott D.

    2006-08-01

    We used frequency-domain reflectometry to make continuous, high-resolution measurements for 22 months of the soil moisture to a depth of 10 m in an Amazonian rain forest. We then used these data to determine how soil moisture varies on diel, seasonal and multi-year timescales, and to better understand the quantitative and mechanistic relationships between soil moisture and forest evapotranspiration. The mean annual precipitation at the site was over 1900 mm. The field capacity was approximately 0.53 m3 m-3 and was nearly uniform with soil depth. Soil moisture decreased at all levels during the dry season, with the minimum of 0.38 m3 m-3 at 3 m beneath the surface. The moisture in the upper 1 m showed a strong diel cycle with daytime depletion due to evapotranspiration. The moisture beneath 1 m declined during both day and night due to the combined effects of evapotranspiration, drainage and a nighttime upward movement of water. The depth of active water withdrawal changed markedly over the year. The upper 2 m of soil supplied 56% of the water used for evapotranspiration in the wet season and 28% of the water used in the dry season. The zone of active water withdrawal extended to a depth of at least 10 m. The day-to-day rates of moisture withdrawal from the upper 10 m of soil during rain-free periods agreed well with simultaneous measurements of whole-forest evapotranspiration made by the eddy covariance technique. The forest at the site was well adapted to the normal cycle of wet and dry seasons, and the dry season had only a small effect on the rates of land-atmosphere water vapour exchange.

  8. Occurrence of Cryptosporidium spp. in Antillean manatees (Trichechus manatus) and Amazonian manatees (Trichechus inunguis) from Brazil.

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    Borges, Joāo Carlos Gomes; Alves, Leucio Câmara; Faustino, Maria Aparecida da Gloria; Marmontel, Miriam

    2011-12-01

    Infections by Cryptosporidium spp. in aquatic mammals is a major concern due to the possibility of the waterborne transmission of oocysts. The aim of the present study was to report the occurrence of Cryptosporidium spp. in Antillean manatees (Trichechus manatus) and Amazonian manatees (Trichechus inunguis) from Brazil. Fecal samples were collected and processed using Kinyoun's method. Positive samples were also submitted to the direct immunofluorescence test. The results revealed the presence of Cryptosporidium spp. oocysts in 12.5% (17/136) of the material obtained from the Antillean manatees and in 4.3% (05/115) of the samples from the Amazonian manatees. Cryptosporidium spp. infection was more prevalent in captive animals than in free-ranging specimens.

  9. Malaria in Brazil: what happens outside the Amazonian endemic region.

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    de Pina-Costa, Anielle; Brasil, Patrícia; Di Santi, Sílvia Maria; de Araujo, Mariana Pereira; Suárez-Mutis, Martha Cecilia; Santelli, Ana Carolina Faria e Silva; Oliveira-Ferreira, Joseli; Lourenço-de-Oliveira, Ricardo; Daniel-Ribeiro, Cláudio Tadeu

    2014-08-01

    Brazil, a country of continental proportions, presents three profiles of malaria transmission. The first and most important numerically, occurs inside the Amazon. The Amazon accounts for approximately 60% of the nation's territory and approximately 13% of the Brazilian population. This region hosts 99.5% of the nation's malaria cases, which are predominantly caused by Plasmodium vivax (i.e., 82% of cases in 2013). The second involves imported malaria, which corresponds to malaria cases acquired outside the region where the individuals live or the diagnosis was made. These cases are imported from endemic regions of Brazil (i.e., the Amazon) or from other countries in South and Central America, Africa and Asia. Imported malaria comprised 89% of the cases found outside the area of active transmission in Brazil in 2013. These cases highlight an important question with respect to both therapeutic and epidemiological issues because patients, especially those with falciparum malaria, arriving in a region where the health professionals may not have experience with the clinical manifestations of malaria and its diagnosis could suffer dramatic consequences associated with a potential delay in treatment. Additionally, because the Anopheles vectors exist in most of the country, even a single case of malaria, if not diagnosed and treated immediately, may result in introduced cases, causing outbreaks and even introducing or reintroducing the disease to a non-endemic, receptive region. Cases introduced outside the Amazon usually occur in areas in which malaria was formerly endemic and are transmitted by competent vectors belonging to the subgenus Nyssorhynchus (i.e., Anopheles darlingi, Anopheles aquasalis and species of the Albitarsis complex). The third type of transmission accounts for only 0.05% of all cases and is caused by autochthonous malaria in the Atlantic Forest, located primarily along the southeastern Atlantic Coast. They are caused by parasites that seem to be (or

  10. Malaria in Brazil: what happens outside the Amazonian endemic region

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    Anielle de Pina-Costa

    2014-08-01

    Full Text Available Brazil, a country of continental proportions, presents three profiles of malaria transmission. The first and most important numerically, occurs inside the Amazon. The Amazon accounts for approximately 60% of the nation’s territory and approximately 13% of the Brazilian population. This region hosts 99.5% of the nation’s malaria cases, which are predominantly caused by Plasmodium vivax (i.e., 82% of cases in 2013. The second involves imported malaria, which corresponds to malaria cases acquired outside the region where the individuals live or the diagnosis was made. These cases are imported from endemic regions of Brazil (i.e., the Amazon or from other countries in South and Central America, Africa and Asia. Imported malaria comprised 89% of the cases found outside the area of active transmission in Brazil in 2013. These cases highlight an important question with respect to both therapeutic and epidemiological issues because patients, especially those with falciparum malaria, arriving in a region where the health professionals may not have experience with the clinical manifestations of malaria and its diagnosis could suffer dramatic consequences associated with a potential delay in treatment. Additionally, because the Anopheles vectors exist in most of the country, even a single case of malaria, if not diagnosed and treated immediately, may result in introduced cases, causing outbreaks and even introducing or reintroducing the disease to a non-endemic, receptive region. Cases introduced outside the Amazon usually occur in areas in which malaria was formerly endemic and are transmitted by competent vectors belonging to the subgenus Nyssorhynchus (i.e., Anopheles darlingi, Anopheles aquasalis and species of the Albitarsis complex. The third type of transmission accounts for only 0.05% of all cases and is caused by autochthonous malaria in the Atlantic Forest, located primarily along the southeastern Atlantic Coast. They are caused by parasites

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

    Science.gov (United States)

    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 km2) of total clearing (forest + non-forest) in Legal Amazonia (967,003 km2). This represents a clear-cutting of 41 % of the original vegetation in the settlements. Out of this total, 72 % (115,634 km2) 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.

  13. Organic matter in the Neoproterozoic cap carbonate from the Amazonian Craton, Brazil

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    Sousa Júnior, Gustavo R.; Nogueira, Afonso C. R.; Santos Neto, Eugênio V.; Moura, Candido A. V.; Araújo, Bruno Q.; Reis, Francisco de A. M.

    2016-12-01

    Bitumen found in Neoproterozoic carbonates from the southern Amazonian Craton, Brazil, represents a great challenge for its geochemical characterization (origin, thermal maturity and the degree of preservation) within a context of petroleum system. This organic material occurs in the basal Araras Group, considered as a Neoproterozoic cap carbonate, composed of dolostones (Mirassol d'Oeste Formation) overlaid by limestones and shales (Guia Formation). Geochemical analyses in samples of carbonate with bitumen from two open pits (Terconi and Tangará quarries) have shown low to very low total organic carbon content. Analyses of representative samples of Guia and Mirassol d'Oeste formations allowed us to obtain Gas chromatography (GC) traces and diagnostic biomarkers. n-C14 to n-C37 alkane distribution patterns in all samples suggests a major contribution of marine algae. Mid-chain monomethyl alkanes (C14sbnd C25) identified in both sets of samples were also reported in all mid to late Proterozoic oils and source rocks. However, there are significant differences among terpane distribution between the Mirassol d'Oeste and Tangará da Serra regions. The integration of organic geochemistry data and geological information suggests an indigenous origin for studied bitumen, primarily accumulated as hydrocarbon fluids migrated to carbonate rocks with higher porosity and permeability, and afterwards, altered to bitumen or migrabitumen. Although further investigations are required, this work provides a significant contribution to the knowledge about the remnant of this hypothetical Neoproterozoic petroleum system developed in the Southern Amazonian Craton.

  14. The Montesbelos mass-flow (southern Amazonian craton, Brazil): a Paleoproterozoic volcanic debris avalanche deposit?

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    Roverato, M.

    2016-07-01

    The present contribution documents the extremely well-preserved Paleoproterozoic architecture of the Montesbelos breccia (named here for the first time), which is interpreted as a rare example of a subaerial paleoproterozoic (>1.85 Ga) granular-dominated mass-flow deposit, few of which are recorded in the literature. Montesbelos deposit is part of the andesitic Sobreiro Formation located in the São Felix do Xingu region, southern Amazonian craton, northern Brazil. The large volume, high variability of textural features, presence of broken clasts, angular low sphericity fragments, mono- to heterolithic character, and the size of the outcrops point to a volcanic debris avalanche flow. Fluviatile sandy material and debris flows are associated with the deposit as a result of post-depositional reworking processes.

  15. Responses of squirrel monkeys to seasonal changes in food availability in an eastern Amazonian forest.

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    Stone, Anita I

    2007-02-01

    Tropical forests are characterized by marked temporal and spatial variation in productivity, and many primates face foraging problems associated with seasonal shifts in fruit availability. In this study, I examined seasonal changes in diet and foraging behaviors of two groups of squirrel monkeys (Saimiri sciureus), studied for 12 months in Eastern Brazilian Amazonia, an area characterized by seasonal rainfall. Squirrel monkeys were primarily insectivorous (79% of feeding and foraging time), with fruit consumption highest during the rainy season. Although monkeys fed from 68 plant species, fruit of Attalea maripa palms accounted for 28% of annual fruit-feeding records. Dietary shifts in the dry season were correlated with a decline in ripe A. maripa fruits. Despite pronounced seasonal variation in rainfall and fruit abundance, foraging efficiency, travel time, and distance traveled remained stable between seasons. Instead, squirrel monkeys at this Eastern Amazonian site primarily dealt with the seasonal decline in fruit by showing dietary flexibility. Consumption of insects, flowers, and exudates increased during the dry season. In particular, their foraging behavior at this time strongly resembled that of tamarins (Saguinus sp.) and consisted of heavy use of seed-pod exudates and specialized foraging on large-bodied orthopterans near the forest floor. Comparisons with squirrel monkeys at other locations indicate that, across their geographic range, Saimiri use a variety of behavioral tactics during reduced periods of fruit availability.

  16. Theileria electrophorin.sp., a parasite of the electric eel Electrophorus electricus (Osteichthyes: Cypriniformes: Gymnotidae) from Amazonian Brazil

    OpenAIRE

    Ralph Lainson

    2007-01-01

    The name Theileria electrophori n.sp. is proposed for a small parasite described in the erythrocytes of the electric eel, Electrophorus electricus, from Amazonian Brazil. Division of the organism in the erythrocyte produces only four bacilliform daughter cells which become scattered in the host cell, without a cruciform or rosette-shaped disposition. Exoerythrocytic meronts producing a large number of merozoites were encountered in Giemsa-stained impression smears of the internal organs, prin...

  17. Two new species in the Matelea stenopetala complex (Apocynaceae, Asclepiadoideae from the Guiana Shield and Amazonian Brazil

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    Alexander Krings

    2012-09-01

    Full Text Available Two new species in the Matelea stenopetala complex (Apocynaceae, Asclepiadoideae are described from the Guiana Shield and Amazonian Brazil: Matelea brevistipitata Krings & Morillo, sp. nov. and M. trichopedicellata Krings & Morillo, sp. nov. The new species belong to a small group of adaxially-pubescent-flowered taxa within the complex, including M. hildegardiana and M. pakaraimensis. The new species are described and a dichotomous key is provided.

  18. Impacts of hydroelectric dams on alluvial riparian plant communities in eastern Brazilian Amazonian

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    LEANDRO VALLE FERREIRA

    2013-09-01

    Full Text Available The major rivers of the Amazon River basin and their biota are threatened by the planned construction of large hydroelectric dams that are expected to have strong impacts on floodplain plant communities. The present study presents forest inventories from three floodplain sites colonized by alluvial riparian vegetation in the Tapajós, Xingu and Tocantins River basins in eastern Amazonian. Results indicate that tree species of the highly specialized alluvial riparian vegetation are clearly distinct among the three river basins, although they are not very distinct from each other and environmental constraints are very similar. With only 6 of 74 species occurring in all three inventories, most tree and shrub species are restricted to only one of the rivers, indicating a high degree of local distribution. Different species occupy similar environmental niches, making these fragile riparian formations highly valuable. Conservation plans must consider species complementarily when decisions are made on where to place floodplain forest conservation units to avoid the irreversible loss of unique alluvial riparian vegetation biodiversity.

  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. Dental caries profile in Monte Negro, Amazonian state of Rondônia, Brazil, in 2008

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    Roosevelt Silva Bastos

    2010-10-01

    Full Text Available OBJECTIVE: This epidemiological survey assessed the dental caries profile in Monte Negro, a small town in the Amazonian state of Rondônia, Brazil, and its relationship with the northern region, national and global goals for oral health in the years 2000 and 2020. MATERIAL AND METHODS: The groups randomly examined were composed of individuals aged 5, 12, 15 to 19, 35 to 44, 65 to 74 years, living in both rural and urban areas. RESULTS: The means dft (standard deviation and DMFT (standard deviation for the groups were, respectively, 3.15 (3.12, 3.41 (2.69, 5.96 (4.19, 16.00 (7.30 and 25.96 (9.82. Caries-free individuals were 34.42%, 14.81% and 8.16% in the preschoolchildren, schoolchildren and adolescent groups, respectively. The Significant Caries Index percentages applied to the two younger groups were 6.65 and 6.70, and they increased to 32.00 in the individuals aged 65 to 74 years. Care Index percentages for adolescents, adults and elderly groups were, respectively, 29.40, 25.00 and 1.41. The dental caries profile in Monte Negro in 2008 shows that, 8 years after the year 2000, no FDI/WHO goal for any age settled in 1982 has been achieved. Dental caries increased with age and the main dental problem of adult and elderly groups was tooth loss. CONCLUSION: Oral health promotion and prevention of oral disease policies are urgent needs. Setting of oral health goals and targets to people living in Monte Negro or Amazonia to be pursuit and achieved in a near future is an important action to do because of the culture, sanitary conditions and socioeconomic aspects of this particular population.

  1. Evaluating the nodulation status of leguminous species from the Amazonian forest of Brazil.

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    de Faria, Sergio M; Diedhiou, Abdala G; de Lima, Haroldo C; Ribeiro, Robson D; Galiana, Antoine; Castilho, Alexandre F; Henriques, João C

    2010-06-01

    Numerous leguminous species are used or have potential uses for timber production, pharmacological products, or land reclamation. Through N(2)-fixation, many leguminous trees contribute to the N-balance of tropical wetlands and rainforests. Therefore, studies of the N(2)-fixation ability of leguminous species appear to be crucial for the better use and conservation of these resources. The global nodulation inventory in the Leguminosae family is constantly being enriched with new records, suggesting the existence of undiscovered nodulated species, especially in tropical natural ecosystems and other hot spots of biodiversity. In this respect, the nodulation of leguminous species from the Amazonian forest of Porto Trombetas (Brazil) was surveyed. Overall, 199 leguminous species from flooded and non-flooded areas, were examined for their nodulation status by combining field observations, seedling inoculations, and screening of N(2)-fixing bacterial strains from the collected nodules. The results revealed a tendency for a higher relative frequency of nodulation in the species from the flooded areas (74%) compared with those from the non-flooded areas (67%). Nodulation was observed in the Caesalpinioideae, Mimosoideae, and Papilionoideae, with 25, 88, and 84% of the examined species in each subfamily, respectively. Of the 137 nodulated leguminous species, 32 including three Caesalpinoideae, 19 Mimosoideae, and 10 Papilionoideae are new records. One new nodulated genus (Cymbosema) was found in the Papilionoideae. Twelve non-nodulating leguminous species were also observed for the first time. The results are discussed based on the systematics of the Leguminosae family and the influence of available nutrients to the legume-bacteria symbiosis.

  2. Primate population densities in three nutrient-poor amazonian terra firme forests of south-eastern Colombia.

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    Palacios, Erwin; Peres, Carlos A

    2005-01-01

    We censused primate populations at three non-hunted 'terra firme' forests of south-eastern Colombian Amazonia. The aggregate biomass densities of diurnal primates at all sites were amongst the lowest recorded for any non-hunted forest in western Amazonia and elsewhere in the Neotropics. Densities of red howler monkeys were low, as is typical in Amazonian terra firme forests far removed from white-water rivers, and densities of woolly monkeys were 1.5-3.5 times lower than those estimated for this species in central-western Brazilian Amazonia. Densities of small to mid-sized primates except for brown capuchins (Cebus apella) and white-faced capuchins (Cebus albifrons) were similar to those of other oligotrophic Amazonian forest sites. Our results are in agreement with other studies showing that terra firme forests of lowland Amazonia typically sustain a low biomass density of primates and other mid-sized to large vertebrates. Large reserves are therefore required to assure the viability of primate populations in oligotrophic systems. Given the escalating negative impacts of human habitat disturbance and hunting in Colombian Amazonia, we urge that a baseline sampling protocol to quantify the abundance and distribution of the harvest-sensitive vertebrate fauna be established within protected areas and the large indigenous reserves so that conservation efforts can be defined and implemented.

  3. Novel biomarkers of mercury-induced autoimmune dysfunction: a Cross-sectional study in Amazonian Brazil

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    Motts, Jonathan A.; Shirley, Devon L.; Silbergeld, Ellen K.; Nyland, Jennifer F.

    2014-01-01

    Mercury is an ubiquitous environmental contaminant, causing both neurotoxicity and immunotoxicity. Given its ability to amalgamate gold, mercury is frequently used in small-scale artisanal gold mining. We have previously reported that elevated serum titers of antinuclear autoantibodies (ANA) are associated with mercury exposures of miners in gold mining. The goal of this project was to identify novel serum biomarkers of mercury-induced immunotoxicity and autoimmune dysregulation. We conducted an analysis of serum samples from a cross-sectional epidemiological study on miners working in Amazonian Brazil. In proteomic screening analyses, samples were stratified based on mercury concentrations and ANA titer and a subset of serum samples (N=12) were profiled using Immune Response Biomarker Profiling ProtoArray protein microarray for elevated autoantibodies. Of the up-regulated autoantibodies in the mercury-exposed cohort, potential target autoantibodies were selected based on relevance to pro-inflammatory and macrophage activation pathways. ELISAs were developed to test the entire sample cohort (N=371) for serum titers to the highest of these autoantibodies (anti-glutathione S-transferase alpha, GSTA1) identified in the high mercury/high ANA group. We found positive associations between elevated mercury exposure and up-regulated serum titers of 3760 autoantibodies as identified by ProtoArray. Autoantibodies identified as potential novel biomarkers of mercury-induced immunotoxicity include antibodies to the following proteins: GSTA1, tumor necrosis factor ligand superfamily member 13, linker for activation of T cells, signal peptide peptidase like 2B, stimulated by retinoic acid 13, and interferon induced transmembrane protein. ELISA analyses confirmed that mercury-exposed gold miners had significantly higher serum titers of anti-GSTA1 autoantibody [unadjusted odds ratio = 89.6; 95% confidence interval: 27.2, 294.6] compared to emerald miners (referent population

  4. Ecomorphological patterns of the fishes inhabiting the tide pools of the Amazonian Coastal Zone, Brazil

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    Bruno Eleres Soares

    Full Text Available The present study was based on the identification of the ecomorphological patterns that characterize the fish species found in tide pools in the Amazonian Coastal Zone (ACZ in the Pará State, Brazil. Representatives of 19 species were collected during two field campaigns in 2011. The dominance, residence status, and trophic guild of each species were established, and morphometric data were obtained for up to 10 specimens of each species. A total of 23 ecomorphological attributes related to locomotion, position in the water column, and foraging behavior were calculated for the analysis of ecomorphological distance. Principal Component Analysis (PCA was utilized for the evaluation of ecomorphological attributes that explained the variation among species. Mantel Test was used to correlate the taxonomic distance with species' morphological patterns and a partial Mantel Test to analyze the correlation among trophic guilds and ecomorphological patterns, controlling the effects of taxonomic distance among species. The analyses revealed two principal axes of the variation related to locomotion, correlated with the width of the caudal peduncle and the shape of the anal fin, as well as the influence of taxonomic distance on the ecomorphological characteristics of the different species. The dominant and resident species both presented a reduced capacity for continuous swimming. The two principal axes identified in relation to the position of the fish in the water column were correlated with the position of the eyes, the area of the pelvic fin, and body shape, with evidence of the influence of taxonomic distance on the morphology of the species. PCA grouped species with pelagic habits with benthonic ones. In the case of foraging behavior, the two principal axes formed by the analysis correlated with the size of the mouth, eye size, and the length of the digestive tract. Species of different guilds were grouped together, indicating a weak relationship

  5. Paleoproterozoic andesitic volcanism in the southern Amazonian craton (northern Brazil); lithofacies analysis and geodynamic setting

    Science.gov (United States)

    Roverato, Matteo; Juliani, Caetano; Capra, Lucia; Dias Fernandes, Carlos Marcelo

    2016-04-01

    Precambrian volcanism played an important role in geological evolution and formation of new crust. Most of the literature on Precambrian volcanic rocks describes settings belonging to subaqueous volcanic systems. This is likely because subaerial volcanic rocks in Proterozoic and Archean volcano-sedimentary succession are poorly preserved due to erosive/weathering processes. The late Paleoproterozoic Sobreiro Formation (SF) here described, seems to be one of the rare exceptions to the rule and deserves particular attention. SF represents the subaerial expression of an andesitic magmatism that, linked with the upper felsic Santa Rosa F., composes the Uatumã Group. Uatumã Group is an extensive magmatic event located in the Xingú region, southwestern of Pará state, Amazonian Craton (northern Brazil). The Sobreiro volcanism is thought to be related to an ocean-continent convergent margin. It is characterized by ~1880 Ma well-preserved calc-alkaline basaltic/andesitic to andesitic lava flows, pyroclastic rocks and associated reworked successions. The superb preservation of its rock-textures allowed us to describe in detail a large variety of volcaniclastic deposits. We divided them into primary and secondary, depending if they result from a direct volcanic activity (pyroclastic) or reworked processes. Our study reinforces the importance of ancient volcanic arcs and rocks contribution to the terrestrial volcaniclastic sedimentation and evolution of plate tectonics. The volcanic activity that produced pyroclastic rocks influenced the amount of detritus shed into sedimentary basins and played a major role in the control of sedimentary dispersal patterns. This study aims to provide, for the first time, an analysis of the physical volcanic processes for the subaerial SF, based in field observation, lithofacies analysis, thin section petrography and less geochemical data. The modern volcanological approach here used can serve as a model about the evolution of Precambrian

  6. Theileria electrophorin.sp., a parasite of the electric eel Electrophorus electricus (Osteichthyes: Cypriniformes: Gymnotidae) from Amazonian Brazil.

    Science.gov (United States)

    Lainson, Ralph

    2007-05-01

    The name Theileria electrophori n.sp. is proposed for a small parasite described in the erythrocytes of the electric eel, Electrophorus electricus, from Amazonian Brazil. Division of the organism in the erythrocyte produces only four bacilliform daughter cells which become scattered in the host cell, without a cruciform or rosette-shaped disposition. Exoerythrocytic meronts producing a large number of merozoites were encountered in Giemsa-stained impression smears of the internal organs, principally in the liver, and are presumably the source of the intraerythrocytic forms of the parasite. This developmental pattern is characteristic of piroplasms within the family Theileriidae, where the author considers the parasite of E. electricus to most appropriately belong. It effectively distinguishes the organism from the dactylosomatid parasites Babesiosoma Jakowska and Nigrelli, 1956 and Dactylosoma Labbé, 1894 also found in fishes. This appears to be the second report of Theileria Bettencourt, Franca and Borges, 1907 in a fish.

  7. Theileria electrophorin.sp., a parasite of the electric eel Electrophorus electricus (Osteichthyes: Cypriniformes: Gymnotidae from Amazonian Brazil

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    Ralph Lainson

    2007-03-01

    Full Text Available The name Theileria electrophori n.sp. is proposed for a small parasite described in the erythrocytes of the electric eel, Electrophorus electricus, from Amazonian Brazil. Division of the organism in the erythrocyte produces only four bacilliform daughter cells which become scattered in the host cell, without a cruciform or rosette-shaped disposition. Exoerythrocytic meronts producing a large number of merozoites were encountered in Giemsa-stained impression smears of the internal organs, principally in the liver, and are presumably the source of the intraerythrocytic forms of the parasite. This developmental pattern is characteristic of piroplasms within the family Theileriidae, where the author considers the parasite of E. electricus to most appropriately belong. It effectively distinguishes the organism from the dactylosomatid parasites Babesiosoma Jakowska and Nigrelli, 1956 and Dactylosoma Labbé, 1894 also found in fishes. This appears to be the second report of Theileria Bettencourt, Franca and Borges, 1907 in a fish.

  8. Effect of 7 yr of experimental drought on vegetation dynamics and biomass storage of an eastern Amazonian rainforest.

    Science.gov (United States)

    da Costa, Antonio Carlos Lola; Galbraith, David; Almeida, Samuel; Portela, Bruno Takeshi Tanaka; da Costa, Mauricio; Silva Junior, João de Athaydes; Braga, Alan P; de Gonçalves, Paulo H L; de Oliveira, Alex A R; Fisher, Rosie; Phillips, Oliver L; Metcalfe, Daniel B; Levy, Peter; Meir, Patrick

    2010-08-01

    *At least one climate model predicts severe reductions of rainfall over Amazonia during this century. Long-term throughfall exclusion (TFE) experiments represent the best available means to investigate the resilience of the Amazon rainforest to such droughts. *Results are presented from a 7 yr TFE study at Caxiuanã National Forest, eastern Amazonia. We focus on the impacts of the drought on tree mortality, wood production and above-ground biomass. *Tree mortality in the TFE plot over the experimental period was 2.5% yr(-1), compared with 1.25% yr(-1) in a nearby control plot experiencing normal rainfall. Differences in stem mortality between plots were greatest in the largest (> 40 cm diameter at breast height (dbh)) size class (4.1% yr(-1) in the TFE and 1.4% yr(-1) in the control). Wood production in the TFE plot was c. 30% lower than in the control plot. Together, these changes resulted in a loss of 37.8 +/- 2.0 Mg carbon (C) ha(-1) in the TFE plot (2002-2008), compared with no change in the control. *These results are remarkably consistent with those from another TFE (at Tapajós National Forest), suggesting that eastern Amazonian forests may respond to prolonged drought in a predictable manner.

  9. Parabolic dunes in north-eastern Brazil

    CERN Document Server

    Duran, O; Bezerra, L J C; Herrmann, H J; Maia, L P

    2007-01-01

    In this work we present measurements of vegetation cover over parabolic dunes with different degree of activation along the north-eastern Brazilian coast. We are able to extend the local values of the vegetation cover density to the whole dune by correlating measurements with the gray-scale levels of a high resolution satellite image of the dune field. The empirical vegetation distribution is finally used to validate the results of a recent continuous model of dune motion coupling sand erosion and vegetation growth.

  10. Emplacement and deformation of the A-type Madeira granite (Amazonian Craton, Brazil)

    Science.gov (United States)

    Siachoque, Astrid; Salazar, Carlos Alejandro; Trindade, Ricardo

    2017-04-01

    The Madeira granite is one of the Paleoproterozoic (1.82 Ga) A-type granite intrusions in the Amazonian Craton. It is elongated in the NE-SW direction and is composed of four facies. Classical structural techniques and the anisotropy of magnetic susceptibility (AMS) method were applied to the study of its internal fabric. Magnetic susceptibility measurements, thermomagnetic curves, remanent coercivity spectra, optical microscopy and SEM (scanning electron microscopy) analyses were carried out on the earlier and later facies of the Madeira granite: the rapakivi granite (RG) and the albite granite (AG) respectively. The last one is subdivided into the border albite granite (BAG) and the core albite granite (CAG) subfacies. AMS fabric pattern is controlled by pure magnetite in all facies, despite significant amounts of hematite in the BAG subfacies. Microstructural observations show that in almost all sites, magnetic fabric correlates to magmatic state fabrics that are defined by a weak NE-SW orientation of mafic and felsic silicates. However, strain mechanisms in both subfacies of AG also exhibit evidence for solid-state deformation at high to moderate temperatures. Pegmatite dyke, strike slip fault (SFA-B-C), hydrothermal vein, normal fault (F1-2) and joint (J) structures were observed and their orientation and kinematics is consistent with the magmatic and solid-state structures. Dykes, SFA-C and F1, are usually orientated along the N70°E/40°N plane, which is nearly parallel to the strike of AMS and magmatic foliations. In contrast, veins, SFB, F2 and some J are oriented perpendicular to the N70°E trend. Kinematic analysis in these structures shows evidence for a dextral sense of movement in the system in the brittle regime. The coherent structural pattern for the three facies of Madeira granite suggests that the different facies form a nested pluton. The coherence in orientation and kinematics from magmatic to high-temperature solid-state, and into the brittle

  11. Schellackia (Apicomplexa: Eimeriidae of the brazilian tree-frog, Phrynohyas venulosa (Amphibia: Anura from Amazonian Brazil

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    I. Paperna

    1995-10-01

    Full Text Available Endogenous stages of a Schellackia species are described in histological sections of the intestine of the tree-frog, Phrynohyas venulosa, from North Brazil. Most oocysts sporulate within the epithelial cells of the gut, but a few were detected in the lamina propria.

  12. [Profile of leprosy patients in a hiperendemic area of Amazonian Maranhão, Brazil].

    Science.gov (United States)

    Aquino, Dorlene Maria Cardoso de; Caldas, Arlene de Jesus Mendes; da Silva, Antônio Augusto Moura; Costa, Jackson Maurício Lopes

    2003-01-01

    An epidemiological cross-sectional study of 207 patients with leprosy disease, was undertaken between August 1998 to november 2000, aiming at evaluating the socioeconomic, demographic and ambiental profiles of the patients as well as physical incapacity due to the disease. The study was performed in the municipality of Buriticupu-Maranh o state, a hiperendemic leprosy area in the Amazonian Maranh o. The level of incapacity was assessed from parameters established by the Brazilian Health Minister. The clinical evaluation and the results of the physical tests were registered in a standardized form. It was observed a predominance of married people (45,9%), with low level of education (56%), being lend workers (40,1%), with familiar income to the minimum wage (76,3%), aged from 14 to 44 years (63,3%), males (60,9%) and brown (67,6%); 44% living in mud huts, 82,6% deposited their excrements in cesspits and 63,8% do not treat the drinking water, 58% utilized well-water and 51,7% do not use treated water for ingestion. The most affected segments of the body were the feet (62,3%), eyes (51,2%) end hands (7,2%), being the higher percentage of physical incapacitaties found among the patients bearing the borderline form of the disease (93%) mainly hands and feet, and in the virchowian form greatest frequency of eyes incapacities. It is concluded that the hyperendemicity associated with the precarious socioeconomic conditions and with a high level of physical incapacities may be involved with the living quality of the patients.

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

    Science.gov (United States)

    2010-10-07

    with an estimated 14% of all plant and animal species within its boundaries [2]. Because speciation is not always accompanied by mor- phological change...this region. Clearing of forest, in combination with an increase in human and domestic animal host abundance, may have led to an A. marajoara...USA. 4Department of Epidemiology, Universidade de Sao Paulo, 715 - Cerqueira Cesar 01246-904 Sao Paulo, Brazil. 5Laboratório de Fisiologia e Controle de

  14. The influence of the Amazonian floodplain ecosystems on the trace element dynamics of the Amazon River mainstem (Brazil).

    Science.gov (United States)

    Viers, Jérôme; Barroux, Guénaël; Pinelli, Marcello; Seyler, Patrick; Oliva, Priscia; Dupré, Bernard; Boaventura, Geraldo Resende

    2005-03-01

    The purpose of this paper is to forecast the role of riverine wetlands in the transfer of trace elements. One of the largest riverine wetlands in the world is the floodplain (várzea) of the Amazon River and its tributaries (Junk and Piedade, 1997). The central Amazon wetlands are constituted by a complex network of lakes and floodplains, named várzeas, that extend over more than 300,000 km2 (Junk, W.J., The Amazon floodplain--a sink or source for organic carbon? In Transport of Carbon and Minerals in Major World Rivers, edited by E.T. Degens, S. Kempe, R. Herrera, SCOPE/UNEP; 267-283, 1985.) and are among the most productive ecosystems in the world due to the regular enrichment in nutrients by river waters In order to understand if the adjacent floodplain of Amazon River have a significant influence on the trace element concentrations and fluxes of the mainstem, the concentrations of selected elements (i.e., Al, Mn, Fe, Co, Cu, Mo, Rb, Sr, Ba, and U) have been measured in the Amazon River water (Manacapuru Station, Amazonas State, Brazil) and in lake waters and plants (leaves) from a várzea(Ilha de Marchantaria, Amazonas State, Brazil) during different periods of the hydrological cycle. Four plant species (two perennial species: Pseudobombax munguba and Salix humboldtiana, and two annual herbaceous plants: Echinochloa polystachya and Eichhornia crassipes) were selected to represent the ecological functioning of the site. Time series obtained for dissolved Mn and Cu (<0.20 microm) in Amazon River water could not be explained by tributary mixing or instream processes only. Therefore, the contribution of the waters transiting the floodplains should be considered. These results suggest that the chemical composition of the waters draining these floodplains is controlled by reactions occurring at sediment-water and plant-water interfaces. Trace elements concentrations in the plants (leaves) vary strongly with hydrological seasonality. Based on the concentration data

  15. Genesis of the largest Amazonian wetland in northern Brazil inferred by morphology and gravity anomalies

    Science.gov (United States)

    Rossetti, Dilce de Fátima; Cassola Molina, Eder; Cremon, Édipo Henrique

    2016-08-01

    The Pantanal Setentrional (PS) is the second largest wetland in Brazil, occurring in a region of northern Amazonia previously regarded as part of the intracratonic Solimões Basin. However, while Paleozoic to Neogene strata are recorded in this basin, the PS constitutes a broad region with an expressive record of only Late Pleistocene and Holocene deposits. The hypothesis investigated in the present work is if these younger deposits were formed within a sedimentary basin having a geological history separated from the Solimões Basin. Due to the location in a remote region of low accessibility, the sedimentary fill of the PS wetland remains largely unknown in subsurface. In the present work, we combine geomorphological and gravity data acquired on a global basis by several satellite gravity missions to approach the geological context of this region. The results revealed a wetland characterized in surface by a low-lying terrain with wedge shape and concave-up geometry that is in sharp contact with highland areas of Precambrian rocks of the Guiana Shield. Such contact is defined by a series of mainly NE- or NW-trending straight lineaments that eventually extend into both the Guiana Shield and the PS wetland. Also of relevance is that a great part of the PS wetland sedimentary cover consists of dominantly sandy deposits preserved as residual paleo-landforms with triangular shapes previously related to megafan depositional systems. These are distributed radially at the northern margin of the PS, with axis toward basement rocks and fringes toward the wetland's center, the latter containing the largest megafan landform. The analysis of gravity anomaly data revealed a main NNE-trending chain ∼500 km in length defined by high gravity values (i.e., up to 60 mGal); these are bounded by negative anomalies as low as -90 mGal. The chain with positive gravity anomaly marks the center of a subsiding area having a geological evolution that differs from the adjacent intracratonic

  16. Amazonian coca.

    Science.gov (United States)

    Plowman, T

    1981-01-01

    A general overview of various aspects of Amazonian coca (Erythroxylum coca var. ipadu) is presented. This plant is considered a distinct variety of coca which has been developed as a cultivated plant in the upper Amazon basin. It differs from typical Andean coca in morphological, physiological and chemical features as well as in the method of preparation and use by Amazonian tribes. The main topics here discussed are the history, distribution, botany, chemistry, origin, methods of preparation and use, and the effects of Amazonian coca.

  17. Paleoproterozoic volcanic centers of the São Félix do Xingu region, Amazonian craton, Brazil: Hydrothermal alteration and metallogenetic potential

    Science.gov (United States)

    da Cruz, Raquel Souza; Fernandes, Carlos Marcello Dias; Villas, Raimundo Netuno Nobre; Juliani, Caetano; Monteiro, Lena Virgínia Soares; Lagler, Bruno; Misas, Carlos Mario Echeverri

    2016-06-01

    Geological, petrographic, scanning electron microscopy, and X-ray diffraction studies revealed hydrothermalized lithotypes evidenced by overprinted zones of potassic, propylitic, sericitic, and intermediate argillic alterations types, with pervasive and fracture-controlled styles, in Paleoproterozoic volcano-plutonic units of the São Félix do Xingu region, Amazonian craton, northern Brazil. The Sobreiro Formation presents propylitic (epidote + chlorite + carbonate + clinozoisite + sericite + quartz ± albite ± hematite ± pyrite), sericitic (sericite + quartz + carbonate), and potassic (potassic feldspar + hematite) alterations. The prehnite-pumpellyite pair that is common in geothermal fields also occurs in this unit. The Santa Rosa Formation shows mainly potassic (biotite + microcline ± magnetite), sericitic (sericite + quartz + carbonate ± chlorite ± gold), and intermediate argillic (montmorillonite + kaolinite/halloysite + illite) alterations. These findings strongly suggest the involvement of magma-sourced and meteoric fluids and draw attention to the metallogenetic potential of these volcanic units for Paleoproterozoic epithermal and rare and base metal porphyry-type mineralizations, similar to those already identified in other portions of the Amazonian craton.

  18. The anamorphic state of Leveillula taurica recorded on Cleome spinosa in north-eastern Brazil

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    Carlos AC

    2012-05-01

    Full Text Available The anamorphic state of Leveillula taurica was found causing a powdery mildew disease on Cleome spinosa in north-eastern Brazil. Its chasmothecial state was not observed on the collected samples. The fungus is illustrated and described. This report represents the first record of this fungus on Cleome spinosa in Brazil.

  19. Lanternfish (Myctophidae from eastern Brazil, southwest Atlantic Ocean

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    Adriana da Costa Braga

    2014-03-01

    Full Text Available Twenty-nine species from 11 genera of Myctophidae were taken in daytime midwater and bottom trawl hauls off eastern Brazil (11º-22ºS. Trawls were performed aboard the French R/V Thalassa to depths from 19 to 2271 m, including samples from shelf, slope and in the vicinity of oceanic banks and seamounts. Diaphus garmani was the most abundant species, accounting for 84% of all identified individuals and with four other species (D. dumerilii, D. brachycephalus, D. perspicillatus and Myctophum obtusirostre accounted for >95% of all myctophids caught. Regarding longitudinal distribution patterns, 16 species are broadly tropical, seven tropical, three subtropical, two temperate and one amphi-Atlantic. For the most abundant and frequent species, highest abundances were associated mainly with cold waters, either South Atlantic Central Water or Antarctic Intermediate Water. Non-metric multidimensional scaling based on species presence-absence in the samples and oceanographic conditions was used to identify spatial distribution of myctophid assemblages. Three assemblages were identified in the studied area: north of Abrolhos Bank, south of Abrolhos Bank, and seamounts.

  20. A successful case of biological invasion: the fish Cichla piquiti, an Amazonian species introduced into the Pantanal, Brazil.

    Science.gov (United States)

    Resende, E K; Marques, D K S; Ferreira, L K S G

    2008-11-01

    The 'tucunaré', Cichla piquiti, an exotic Amazonian fish has become established along the left bank of the Paraguay River in the Pantanal. It was introduced by escaping from culture ponds in the Upper Piquiri River and spread downstream, along the lateral flooded areas of that river, continuing through the clear waters of the left bank of the Paraguay River and reaching south as far as the Paraguai Mirim and Negrinho rivers. Adult spawners have been found in the region, meaning that it is a self-sustained population. Reproduction occurs in the period of low waters. They were found feeding on fishes of lentic environments belonging to the families Characidae, Cichlidae and Loricariidae. Until the end of 2004, its distribution was restricted to the left bank of the Paraguay River, but in March 2005, some specimens were found on the right bank, raising a question for the future: what will be the distribution area of the tucunaré in the Pantanal? Information about its dispersion is increasing: it is known to be in the Tuiuiú Lake, Pantanal National Park and in the Bolivian Pantanal, all of them on the right bank of the Paraguay River. The hypothesis that the 'tucunaré' could not cross turbid waters, such as in the Paraguay River, was refuted by these recent findings. Possibly, the tucunaré's capacity to lay more than one batch of eggs in a reproductive period, as well as its care of eggs and young, lead them to establish themselves successfully in new environments, as has been observed in the Pantanal and other localities.

  1. Nematodes as indicators of shrimp farm impact on an amazonian estuary (Curuçá, Pará, Brazil

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    Virag Venekey

    2016-03-01

    Full Text Available Abstract Shrimp farming reduces demand on wild fishery stocks and avoids environmental damage resulting from fishing practices, however, it has the potential to affect the water quality if not properly managed. In this study the impacts of a shrimp farm in an Amazonian estuary were evaluated, focusing on changes in nematodes regarding taxonomic composition, richness, density and diversity. Sampling was conducted in August 2004 (dry season and January 2005 (rainy season in the river at stations situated upstream and downstream at different distances from the main source of farm effluent discharge. Thirty-eight genera were recorded with Terschellingia dominating in the dry season and Terschellingia, Daptonema, Ptycholaimellus and Gomphionema in the rainy season. Abundances were within the range recorded in other estuaries and together with genera richness and diversity showed a strong temporal pattern with significantly higher values in the rainy season. No clear patterns of changes were observed at the stations. Some signs of organic enrichment were detected but they were not yet intense, probably a consequence of the strong local hydrodynamics and the age of the shrimp farm, which was just starting its operation. We recommend that in future studies on farming impacts a combination of factors, beyond the physical and chemical parameters of the water and sediments or taxonomic refinement, should be taken into account - such as the duration of the operation of the farm, the area occupied by ponds and the farm's production. Furthermore, we also believe that nematodes are a useful tool for evaluating aquaculture impacts due to the ease of sampling and because they are organisms at the base of marine food chain.

  2. Cultural attitudes are stronger predictors of bushmeat consumption and preference than economic factors among urban Amazonians from Brazil and Colombia

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    Carla Morsello

    2015-12-01

    Full Text Available Bushmeat consumption persists in urban areas in the Neotropics, yet knowledge of its scale and the relative importance of cultural and economic factors in determining consumption and preference remain elusive. Moreover, the roles of cultural beliefs, social norms, and attitudes in driving urban bushmeat consumption are rarely evaluated. Therefore, we explored in this article the factors that influence consumption and preference for bushmeat in Amazonian towns. Given the availability of other sources of animal protein and the cultural and social importance of bushmeat in the region, we hypothesized that cultural attributes should be better predictors than economic factors of bushmeat consumption and preference. Data analysis involved fitting two-level mixed-effects regressions (random intercepts to a structured sample of 227 individuals (99 households from four towns in the Brazilian (Tabatinga and Atalaia do Norte and Colombian (Leticia and Puerto Nariño Amazon. The results indicate that a third of the interviewees had consumed bushmeat in the past month, which had primarily been harvested by the family or received as a gift rather than obtained through trade. In general, both economic and cultural factors predicted bushmeat consumption and preference, but the objective proxy for culture, individual origin, was unimportant. Among the tested indicators, the strongest predictor was the importance of bushmeat to social relations. Moreover, informal social norms, such as the greater importance attributed to taboos, tended to decrease the average number of wild species that a person would eat, whereas attitudes toward the illegality of hunting were less important. The two economic indicators, increased income and wealth, tended to decrease preference for bushmeat and the likelihood of consumption. Our findings highlight the importance of human beliefs, attitudes, and social norms to the understanding of bushmeat consumption and preference and may

  3. A successful case of biological invasion: the fish Cichla piquiti, an Amazonian species introduced into the Pantanal, Brazil

    Directory of Open Access Journals (Sweden)

    EK. Resende

    Full Text Available The "tucunaré", Cichla piquiti, an exotic Amazonian fish has become established along the left bank of the Paraguay River in the Pantanal. It was introduced by escaping from culture ponds in the Upper Piquiri River and spread downstream, along the lateral flooded areas of that river, continuing through the clear waters of the left bank of the Paraguay River and reaching south as far as the Paraguai Mirim and Negrinho rivers. Adult spawners have been found in the region, meaning that it is a self-sustained population. Reproduction occurs in the period of low waters. They were found feeding on fishes of lentic environments belonging to the families Characidae, Cichlidae and Loricariidae. Until the end of 2004, its distribution was restricted to the left bank of the Paraguay River, but in March 2005, some specimens were found on the right bank, raising a question for the future: what will be the distribution area of the tucunaré in the Pantanal? Information about its dispersion is increasing: it is known to be in the Tuiuiú Lake, Pantanal National Park and in the Bolivian Pantanal, all of them on the right bank of the Paraguay River. The hypothesis that the "tucunaré" could not cross turbid waters, such as in the Paraguay River, was refuted by these recent findings. Possibly, the tucunaré's capacity to lay more than one batch of eggs in a reproductive period, as well as its care of eggs and young, lead them to establish themselves successfully in new environments, as has been observed in the Pantanal and other localities.

  4. Sinopse das espécies de Marlierea Cambess. (Myrtaceae na Amazônia brasileira Sinopse of the species of Marlierea Cambess. (Myrtaceae in Amazonian Brazil

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    Alessandro Silva do Rosário

    2006-03-01

    Full Text Available O estudo de Marlierea Cambess. na Amazônia Brasileira tem como principal objetivo atualizar os dados sobre a morfologia e taxonomia das espécies da região, bem como fornecer subsídios para esclarecer a separação de Marlierea de Myrcia DC. ex Guill., conforme sugerem alguns autores. Na Amazônia Brasileira, Marlierea está representada por 11 espécies (Marlierea bipennis (O. Berg McVaugh, M. caudata McVaugh, M. ensiformis McVaugh, M. ferruginea (Poir. McVaugh, M. mcvaughii B. Holst, M. scytophylla Diels, M. spruceana O. Berg, M. subulata McVaugh, M. summa McVaugh, M. umbraticola (Kunth O. Berg e M. velutina McVaugh e uma mal conhecida (M. obumbrans (O. Berg Nied., habitando principalmente áreas de formações florestais. O gênero se caracteriza pelo hábito arbóreo ou arbustivo; folhas opostas (exceto em M. velutina que pode apresentar folhas opostas e/ou alternas; as inflorescências em panículas (de fascículos, racemos, cimeiras ou dicásios; botões florais geralmente fechados, abertura irregular do cálice, em 4-5 lobos, pétalas freqüentemente ausentes. Os Estados do Amazonas e Pará representam os dois principais centros de distribuição dessas espécies, sendo M. spruceana e M. umbraticola as espécies mais comuns. Marlierea obumbrans será melhor estudada posteriormente, devido apresentar sua delimitação taxonômica confusa entre Myrcia e Marlierea.A morphological study of Marlierea Cambess. occurring in Amazonian Brazil was carried out in order to obtain a better understanding of the morphology and taxonomy of all species in the region and to provide data to elucidate the taxonomic segregation of Marlierea from the morphologically similar Myrcia DC. ex Guill. In Amazonian Brazil, Marlierea is represented by 11, primarily forest, species (Marlierea bipennis (O. Berg McVaugh, M. caudata McVaugh, M. ensiformis McVaugh, M. ferruginea (Poir. McVaugh, M. mcvaughii B. Holst, M. scytophylla Diels, M. spruceana O. Berg, M

  5. Environmental integrity and damselfly species composition in Amazonian streams at the "arc of deforestation" region, Mato Grosso, Brazil

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    Leandro Schlemmer Brasil

    2014-09-01

    Full Text Available AIMS: Investigated how the loss of environmental integrity affects damselfly species composition in nine sites with different levels of environmental integrity in a Cerrado-Amazon transition region known as "arc of deforestation" in Mato Grosso State, Brazil. We also tested the influence of environmental variables on species composition. METHODS: We collected in transects of 100 m and used ordination (PCoA and simple linear regression. RESULTS: Species composition was strongly influenced by the environmental quality of sites, and the best model to explain species composition included variables related to channel morphology. CONCLUSIONS: These results are connected to the environmental homogenization and loss of environmental integrity as a result of extensive agricultural practices which alter stream communities of dragonflies in this region.

  6. Screening of Amazonian plants from the Adolpho Ducke forest reserve, Manaus, state of Amazonas, Brazil, for antimicrobial activity

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    Ana Lúcia Basílio Carneiro

    2008-02-01

    Full Text Available Tropical forests are species-rich reserves for the discovery and development of antimicrobial drugs. The aim of this work is to investigate the in vitro antimicrobial potential of Amazon plants found within the National Institute on Amazon Research's Adolpho Ducke forest reserve, located in Manaus, state of Amazonas, Brazil. 75 methanol, chloroform and water extracts representing 12 plant species were tested for antimicrobial activity towards strains of Mycobacterium smegmatis, Escherichia coli, Streptococcus sanguis, Streptococcus oralis, Staphylococcus aureus and Candida albicans using the gel-diffusion method. Active extracts were further evaluated to establish minimum inhibitory concentrations (MIC and antimicrobial profiles using bioautography on normal-phase thin-layer chromatography plates. Diclinanona calycina presented extracts with good antimicrobial activity and S. oralis and M. smegmatis were the most sensitive bacteria. D. calycina and Lacmellea gracilis presented extracts with the lowest MIC (48.8 µg/ml. D. calycina methanol and chloroform leaf extracts presented the best overall antimicrobial activity. All test organisms were sensitive to D. calycina branch chloroform extract in the bioautography assay. This is the first evaluation of the biological activity of these plant species and significant in vitro antimicrobial activity was detected in extracts and components from two species, D. calycina and L. gracilis.

  7. Lactation curve of cross-bred buffalo under two production systems in the Amazonian region of Brazil

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    A.C. Ribeiro Neto

    2010-02-01

    Full Text Available This study was conducted at the Agroforestry Research Center of EMBRAPA (CPAFRO, Rondônia, Brazil, to evaluate the lactation curve of crosss-bred buffalo [Murrah (M, Mediterranean (Me and Jafarabadi(J] under two production systems. Production system one (PS1 corresponded to the period of 1984 to 1998 where animals (4471 observation were milked once a day and received only pasture without supplementation. Production system two (PS2 corresponded to the period of 1999 to 2002 where animals (458 observations were milked twice daily with concentrate supplementation to pasture. Eight mathematical functions were used: Inverse Polynomial, Linear Hyperbolic, Incomplete Gamma, Logarithmic, Logarithmic Quadratic, Linear, Quadratic and Jenkins & Ferrel. Statistical analysis was conducted using PROC NLIN of SAS (2005. Results showed that for both production systems, Incomplete Gama was the best function to describe the lactation curve. Values of coefficient of determination, standard-deviation, coefficient of variation and standard-error were 95%, 0.068, 7.20, and 0.003, respectively. The corresponding values for PS2 were 96%, 0.200, 2.12, and 0.003. Values of the lactation curve parameters (a, b, and c for PS1 and PS2, respectively, were (a 7.0035923 and 10.9209, (b -0.1080043 and -0.1614882, (c 0.0434868 and 0.0679365.

  8. Mosquito-Disseminated Insecticide for Citywide Vector Control and Its Potential to Block Arbovirus Epidemics: Entomological Observations and Modeling Results from Amazonian Brazil.

    Science.gov (United States)

    Abad-Franch, Fernando; Zamora-Perea, Elvira; Luz, Sérgio L B

    2017-01-01

    Mosquito-borne viruses threaten public health worldwide. When the ratio of competent vectors to susceptible humans is low enough, the virus's basic reproductive number (R0) falls below 1.0 (each case generating, on average, <1.0 additional case) and the infection fades out from the population. Conventional mosquito control tactics, however, seldom yield R0 < 1.0. A promising alternative uses mosquitoes to disseminate a potent growth-regulator larvicide, pyriproxyfen (PPF), to aquatic larval habitats; this kills most mosquito juveniles and substantially reduces adult mosquito emergence. We tested mosquito-disseminated PPF in Manacapuru, a 60,000-inhabitant city (~650 ha) in Amazonian Brazil. We sampled juvenile mosquitoes monthly in 100 dwellings over four periods in February 2014-January 2016: 12 baseline months, 5 mo of citywide PPF dissemination, 3 mo of focal PPF dissemination around Aedes-infested dwellings, and 3 mo after dissemination ended. We caught 19,434 juvenile mosquitoes (66% Aedes albopictus, 28% Ae. aegypti) in 8,271 trap-months. Using generalized linear mixed models, we estimated intervention effects on juvenile catch and adult emergence while adjusting for dwelling-level clustering, unequal sampling effort, and weather-related confounders. Following PPF dissemination, Aedes juvenile catch decreased by 79%-92% and juvenile mortality increased from 2%-7% to 80%-90%. Mean adult Aedes emergence fell from 1,077 per month (range 653-1,635) at baseline to 50.4 per month during PPF dissemination (range 2-117). Female Aedes emergence dropped by 96%-98%, such that the number of females emerging per person decreased to 0.06 females per person-month (range 0.002-0.129). Deterministic models predict, under plausible biological-epidemiological scenarios, that the R0 of typical Aedes-borne viruses would fall from 3-45 at baseline to 0.004-0.06 during PPF dissemination. The main limitations of our study were that it was a before-after trial lacking truly

  9. Mosquito-Disseminated Insecticide for Citywide Vector Control and Its Potential to Block Arbovirus Epidemics: Entomological Observations and Modeling Results from Amazonian Brazil

    Science.gov (United States)

    Abad-Franch, Fernando; Luz, Sérgio L. B.

    2017-01-01

    Background Mosquito-borne viruses threaten public health worldwide. When the ratio of competent vectors to susceptible humans is low enough, the virus’s basic reproductive number (R0) falls below 1.0 (each case generating, on average, <1.0 additional case) and the infection fades out from the population. Conventional mosquito control tactics, however, seldom yield R0 < 1.0. A promising alternative uses mosquitoes to disseminate a potent growth-regulator larvicide, pyriproxyfen (PPF), to aquatic larval habitats; this kills most mosquito juveniles and substantially reduces adult mosquito emergence. We tested mosquito-disseminated PPF in Manacapuru, a 60,000-inhabitant city (~650 ha) in Amazonian Brazil. Methods and Findings We sampled juvenile mosquitoes monthly in 100 dwellings over four periods in February 2014–January 2016: 12 baseline months, 5 mo of citywide PPF dissemination, 3 mo of focal PPF dissemination around Aedes-infested dwellings, and 3 mo after dissemination ended. We caught 19,434 juvenile mosquitoes (66% Aedes albopictus, 28% Ae. aegypti) in 8,271 trap-months. Using generalized linear mixed models, we estimated intervention effects on juvenile catch and adult emergence while adjusting for dwelling-level clustering, unequal sampling effort, and weather-related confounders. Following PPF dissemination, Aedes juvenile catch decreased by 79%–92% and juvenile mortality increased from 2%–7% to 80%–90%. Mean adult Aedes emergence fell from 1,077 per month (range 653–1,635) at baseline to 50.4 per month during PPF dissemination (range 2–117). Female Aedes emergence dropped by 96%–98%, such that the number of females emerging per person decreased to 0.06 females per person-month (range 0.002–0.129). Deterministic models predict, under plausible biological-epidemiological scenarios, that the R0 of typical Aedes-borne viruses would fall from 3–45 at baseline to 0.004–0.06 during PPF dissemination. The main limitations of our study were

  10. Mosquito-Disseminated Insecticide for Citywide Vector Control and Its Potential to Block Arbovirus Epidemics: Entomological Observations and Modeling Results from Amazonian Brazil.

    Directory of Open Access Journals (Sweden)

    Fernando Abad-Franch

    2017-01-01

    Full Text Available Mosquito-borne viruses threaten public health worldwide. When the ratio of competent vectors to susceptible humans is low enough, the virus's basic reproductive number (R0 falls below 1.0 (each case generating, on average, <1.0 additional case and the infection fades out from the population. Conventional mosquito control tactics, however, seldom yield R0 < 1.0. A promising alternative uses mosquitoes to disseminate a potent growth-regulator larvicide, pyriproxyfen (PPF, to aquatic larval habitats; this kills most mosquito juveniles and substantially reduces adult mosquito emergence. We tested mosquito-disseminated PPF in Manacapuru, a 60,000-inhabitant city (~650 ha in Amazonian Brazil.We sampled juvenile mosquitoes monthly in 100 dwellings over four periods in February 2014-January 2016: 12 baseline months, 5 mo of citywide PPF dissemination, 3 mo of focal PPF dissemination around Aedes-infested dwellings, and 3 mo after dissemination ended. We caught 19,434 juvenile mosquitoes (66% Aedes albopictus, 28% Ae. aegypti in 8,271 trap-months. Using generalized linear mixed models, we estimated intervention effects on juvenile catch and adult emergence while adjusting for dwelling-level clustering, unequal sampling effort, and weather-related confounders. Following PPF dissemination, Aedes juvenile catch decreased by 79%-92% and juvenile mortality increased from 2%-7% to 80%-90%. Mean adult Aedes emergence fell from 1,077 per month (range 653-1,635 at baseline to 50.4 per month during PPF dissemination (range 2-117. Female Aedes emergence dropped by 96%-98%, such that the number of females emerging per person decreased to 0.06 females per person-month (range 0.002-0.129. Deterministic models predict, under plausible biological-epidemiological scenarios, that the R0 of typical Aedes-borne viruses would fall from 3-45 at baseline to 0.004-0.06 during PPF dissemination. The main limitations of our study were that it was a before-after trial lacking

  11. Metal sorption and mineral precipitation by bacteria in two Amazonian river systems: Rio Solimões and Rio Negro, Brazil

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    Konhauser, K. O.; Fyfe, W. S.; Ferris, F. G.; Beveridge, T. J.

    1993-12-01

    The surfaces of epiphytic and episammic bacteria from the solute-rich waters of the Rio Solimões, Brazil, interacted with available cations in solution and provided major sites for iron deposition. Once bound to the bacteria, the iron served as nucleation sites for the formation and growth of fine-grained authigenic mineral phases. Because of progressive mineralization, the precipitates exhibited a wide range of morphologies, from amorphous "gel-like" to crystalline structures. Complete encrustation of some bacterial cells was observed. The most abundant mineral phase associated with the bacteria was a complex (Fe,Al) silicate with a variable composition. Energy-dispersive X-ray spectroscopy suggested that the gel-like structures were similar in composition to a chamositic clay, whereas the crystalline phases were increasingly kaolinitic. Bacteria collected from the solute-deficient waters of the Rio Negro remained conspicuously unmineralized, suggesting that metal sorption and biomineralization largely reflect the availability of dissolved metals in the water column. In a solute-rich river system, the fate of the metal-loaded bacteria has profound implications for the transfer of metals from the hydrosphere to the sediment. Through diagenesis, the bound metals may either be recycled to the overlying water column or become immobilized as stable mineral phases. If the latter occurs, microorganisms will have played an important role in metal deposition, low-temperature clay formation, and, invariably, mudstone diagenesis. This implies that in the geologic record, microorganisms may have been instrumental in the genesis of many sedimentary rocks of fluvial origin.

  12. Thermal structure of the Poraquê lake, Central Amazonian, Brazil = Estrutura térmica do lago Poraquê, Amazônia Central, Brasil

    OpenAIRE

    Fabio Marques Aprile

    2011-01-01

    Thermal gradient of a Central Amazonian lake was studied to establish a link between seasonal variations in the water level, temperature, suspended particulate matter (SPM) and thermal stratification. Bimonthly measurements of temperature and PAR radiation were made at 0.25 m intervals from the surface to bottom from February 2004 to July 2006. Daily occurs full vertical mixing of the water column, and classic thermal stratification was not observed in the period. The effect of the winds asso...

  13. Floristic composition and diversity of Amazonian rainforest bryophytes in the state of Acre, Brazil Composição florística e diversidade de briófitas em floresta no estado do Acre, Brasil

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    Denise Pinheiro da Costa

    2003-01-01

    Full Text Available Bryophyte diversity in Amazonian Brazil is high, presently recorded at 514 species distributed among 36 families and 89 genera. Comparisions of species richness among the Amazonian states of Brazil suggests that the bryoflora of Acre is still underestimated, presently recorded at 106 species distributed among 33 families and 63 genera. After two field trips, the diversity increased 50% showing that the bryoflora is still poorly known. Collection data and comments on morphology, ecology and distribution are given for sixty-two species of bryophytes collected in the state of Acre, Brazil, which are new (fifty-two species or interesting floristic records (ten species. Microlejeunea crenulifolia (Gottsche Steph. and Stictolejeunea balfourdii Mitt. are new records for Brazil and fifty species are new records for Acre.A diversidade de briófitas na região Amazônica brasileira é alta, sendo citado atualmente, 514 espécies, em 36 famílias e 89 gêneros. Comparações entre a riqueza de espécies dos estados da Amazônia brasileira sugerem que a brioflora do Acre ainda é subestimada, contando atualmente com 106 espécies, distribuídas em 33 famílias e 63 gêneros. Após duas excursões científicas, a diversidade para o estado aumentou em 50 %, demonstrando que a brioflora ainda é pouco conhecida. Dados sobre a morfologia, ecologia e distribuição geográfica são apresentados para sessenta e duas espécies de briófitas coletadas no estado do Acre, Brasil, as quais são registros florísticos novos (cinquenta e duas espécies ou interessantes (dez espécies. Microlejeunea crenulifolia (Gottsche Steph. e Stictolejeunea balfourdii Mitt. são citadas pela primeira vez para o Brasil e cinquenta espécies são novas ocorrências para o estado do Acre.

  14. Equatorial E region electric fields at the dip equator: 1. Variabilities in eastern Brazil and Peru

    Science.gov (United States)

    Moro, J.; Denardini, C. M.; Resende, L. C. A.; Chen, S. S.; Schuch, N. J.

    2016-10-01

    The equatorial electrojet (EEJ) is an intense eastward ionospheric electric current centered at about 105 km of altitude along the dip equator, set up by the global neutral wind dynamo that generates the eastward zonal (Ey) and the daytime vertical (Ez) electric fields. The temporal variation of the EEJ is believed to be well understood. However, the longitudinal variability of the Ey and Ez between 100 and 110 km is still quite scarce. Due to their importance overall phenomenology of the equatorial ionosphere, we investigate the variabilities of the Ey and Ez inferred from measurements of the Doppler frequency of Type II echoes provided by coherent backscatter radars installed in locations close to the magnetic equator in the eastern Brazil (2.33°S, 44.20°W) and Peru (11.95°S, 76.87°W). This study is based on long-term (609 days for both systems) radar soundings collected from 2001 to 2010. The variabilities of the electric fields are studied in terms of the position of the soundings with respect to the dip equator and the magnetic declination angle. Among the results, Ey and Ez show longitudinal dependence, being higher in Peru than east Brazil. Under quiet geomagnetic activity, the mean diurnal variations of Ey ranged from 0.21 to 0.35 mV/m between 8 and 18 h (LT) in Brazil and from 0.23 mV/m to 0.45 mV/m in Peru, while the mean diurnal variations of the Ez ranges from 7.09 to 8.80 mV/m in Brazil and from 9.00 to 11.18 mV/m in Peru.

  15. The influence of particles recycling on the geochemistry of sediments in a large tropical dam lake in the Amazonian region, Brazil

    Science.gov (United States)

    Fonseca, Rita; Pinho, Catarina; Oliveira, Manuela

    2016-12-01

    As a result of over-erosion of soils, the fine particles, which contain the majority of nutrients, are easily washed away from soils, which become deficient in a host of components, accumulating in lakes. On one hand, the accumulation of nutrients-rich sediments are a problem, as they affect the quality of the overlying water and decrease the water storage capacity of the system; on the other hand, sediments may constitute an important resource, as they are often extremely rich in organic and inorganic nutrients in readily available forms. In the framework of an extensive work on the use of rock related materials to enhance the fertility of impoverish soils, this study aimed to evaluate the role on the nutrients cycle, of particles recycling processes from the watershed to the bottom of a large dam reservoir, at a wet tropical region under high weathering conditions. The study focus on the mineralogical transformations that clay particles undergo from the soils of the drainage basin to their final deposition within the reservoir and their influence in terms of the geochemical characteristics of sediments. We studied the bottom sediments that accumulate in two distinct seasonal periods in Tucuruí reservoir, located in the Amazonian Basin, Brazil, and soils from its drainage basin. The surface layers of sediments in twenty sampling points with variable depths, are representative of the different morphological sections of the reservoir. Nineteen soil samples, representing the main soil classes, were collected near the margins of the reservoir. Sediments and soils were subjected to the same array of physical, mineralogical and geochemical analyses: (1) texture, (2) characterization and semi-quantification of the clay fraction mineralogy and (3) geochemical analysis of the total concentration of major elements, organic compounds (organic C and nitrogen), soluble fractions of nutrients (P and K), exchangeable fractions (cation exchange capacity, exchangeable bases and

  16. Ectoparasites of bats (Mammalia: Chiroptera) in Atlantic forest fragments in north-eastern Brazil.

    Science.gov (United States)

    Bezerra, Rayanna Hellem Santos; de Vasconcelos, Pedro Fonseca; Bocchiglieri, Adriana

    2016-10-01

    In Brazil, most studies involving parasites of bats (bat flies) treat the mid-west, south-east, and south of the country. This work aimed to characterize the ectoparasites community associated with bats in the Atlantic forest in the state of Sergipe, north-eastern Brazil. Sampling was conducted between January and June 2013 in the Serra de Itabaiana National Park (PNSI) and between November 2013 and June 2015 in the Wildlife Refuge Mata do Junco (RVSMJ). Parasitological indexes were determined, and the influence of host sex and the seasonality in prevalence rates and mean intensity for the most abundant parasites was evaluated. Some 129 parasites were collected in PNSI and 296 in RVSMJ, and 100 and 70.6 %, respectively, belong to the family Streblidae. The differences in parasitological rates in Sergipe in relation to other studies may be associated with the environmental characteristics and the composition of the host community. The influence of sex and the seasonal prevalence of Speiseria ambigua and Trichobius joblingi, associated with Carollia perspicillata, may be associated with a lower rate of female captures and low sampling in the dry season. This is a pioneer study in Sergipe that reveals the occurrence of 16 species of streblids and representatives of Acari and Basilia spp., highlighting the need for more studies to increase the wealth and understanding of host-parasite associations in the state.

  17. Biogeography of Anurans from the Poorly Known and Threatened Coastal Sandplains of Eastern Brazil

    Science.gov (United States)

    Xavier, Ariane Lima; Guedes, Thaís Barreto; Napoli, Marcelo Felgueiras

    2015-01-01

    The east coast of Brazil comprises an extensive area inserted in the Tropical Atlantic Domain and is represented by sandy plains of beach ridges commonly known as Restingas. The coastal environments are unique and house a rich amphibian fauna, the geographical distribution patterns of which are incipient. Biogeographical studies can explain the current distributional patterns and provide the identification of natural biogeographical units. These areas are important in elucidating the evolutionary history of the taxa and the areas where they occur. The aim of this study was to seek natural biogeographical units in the Brazilian sandy plains of beach ridges by means of distribution data of amphibians and to test the main predictions of the vicariance model to explain the patterns found. We revised and georeferenced data on the geographical distribution of 63 anuran species. We performed a search for latitudinal distribution patterns along the sandy coastal plains of Brazil using the non-metric multidimensional scaling method (NMDS) and the biotic element analysis to identify natural biogeographical units. The results showed a monotonic variation in anuran species composition along the latitudinal gradient with a break in the clinal pattern from 23°S to 25°S latitude (states of Rio de Janeiro to São Paulo). The major predictions of the vicariance model were corroborated by the detection of four biotic elements with significantly clustered distribution and by the presence of congeneric species distributed in distinct biotic elements. The results support the hypothesis that vicariance could be one of the factors responsible for the distribution patterns of the anuran communities along the sandy coastal plains of eastern Brazil. The results of the clusters are also congruent with the predictions of paleoclimatic models made for the Last Glacial Maximum of the Pleistocene, such as the presence of historical forest refugia and biogeographical patterns already detected

  18. Phlebotominae sand flies (Diptera: Psychodidae: potential vectors of American cutaneous leishmaniasis agents in the area associated with the Santo Antônio Hydroelectric System in Western Amazonian Brazil

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    Allan Kardec Ribeiro Galardo

    2015-06-01

    Full Text Available INTRODUCTION: An entomological study was conducted as part of a vector-monitoring program in the area associated with the Santo Antônio hydroelectric system in State of Rondônia, Western Amazonian Brazil. METHODS: Fourteen sampling sites were surveyed to obtain data on the potential vectors of Leishmania spp. in the area. Sand flies were collected from 2011 to 2014 during the months of January/February (rainy season, May/June (dry season, and September/October (intermediary season using light traps arranged in three vertical strata (0.5, 1, and 20m. RESULTS : A total of 7,575 individuals belonging to 62 species/subspecies were collected. The five most frequently collected sand flies were Psychodopygus davisi (Root (36.67%, Trichophoromyia ubiquitalis (Mangabeira (8.51%, Nyssomyia umbratilis (Ward & Fraiha (6.14%, Bichromomyia flaviscutellata (Mangabeira (5.74%, and Psychodopygus complexus (Mangabeira (5.25%. These species have been implicated in the transmission of American cutaneous leishmaniasis agents in the Brazilian Amazon region and described as potential vectors of this disease in the study area. CONCLUSIONS: Additional surveillance is needed, especially in areas where these five species of sand fly are found.

  19. Ecology of Lutzomyia longipalpis in an area of visceral leishmaniasis transmission in north-eastern Brazil.

    Science.gov (United States)

    Costa, Pietra Lemos; Dantas-Torres, Filipe; da Silva, Fernando José; Guimarães, Vanessa Cristina Fitipaldi Veloso; Gaudêncio, Kamila; Brandão-Filho, Sinval Pinto

    2013-05-01

    Visceral leishmaniasis is a major public health issue in South America, where the disease is rapidly spreading. Changes in ecology and distribution of the principal vector, Lutzomyia longipalpis are among the factors accounting for the increasing incidence of the disease in this region. However, information about the ecology of L. longipalpis is still incipient, which may directly impair the implementation of effective control programs. Herein, the ecology of L. longipalpis was studied in a focus of visceral leishmaniasis in north-eastern Brazil. From August 2009 to August 2010, phlebotomine sand flies were monthly collected in four localities using CDC light traps (~37 per month) and a lantern-baited Shannon trap with mouth aspirators. A total of 24,226 phlebotomine sand flies were collected with light traps and 375 with mouth aspirators. The most abundant species was L. longipalpis, representing 97.9% of the specimens collected with light traps and 91.5% with the mouth aspirator. Other species (Lutzomyia evandroi, Lutzomyia lenti and Lutzomyia sallesi) were found in low numbers. Most phlebotomine sand flies (94.6%) were collected at chicken coops and corrals. No significant correlation was found between the monthly abundance of phlebotomine sand flies and the monthly averages of temperature, relative humidity or rainfall. However, interestingly enough, 82.4% of L. longipalpis specimens were collected in months when relative humidity surpassed 75%. This study points out that this vector is well adapted to live in different habitats and to different climate conditions. It also suggests that some north-eastern populations of L. longipalpis may be more xerotolerant than southern populations. Further studies to assess the relationship between microclimate and L. longipalpis density in different Brazilian regions are advised.

  20. Spatial and temporal variation in artisanal catches of dolphinfish Coryphaena hippurus off north-eastern Brazil.

    Science.gov (United States)

    Nóbrega, M F; Kinas, P G; Lessa, R; Ferrandis, E

    2015-02-01

    The sampling of fish from the artisanal fleet operating with surface lines off north-eastern Brazil was carried out between 1998 and 2000. Generalized linear models (GLMs) were used to standardize mean abundance indices using catch and fishing effort data on dolphinfish Coryphaena hippurus and to identify abundance trends in time and space, using 1215 surface line deployments. A standard relative abundance index (catch per unit effort, CPUE) was estimated for the most frequent vessels used in the sets, employing factors and coefficients generated in the GLMs. According to the models, C. hippurus catches are affected by the operating characteristics and power of different fishing vessels. These differences highlight the need for standardization of catch and effort data for artisanal fisheries. The highest mean abundance values for C. hippurus were off the state of Rio Grande do Norte, with an increasing tendency in areas with greater depths and more distant from the coast, reaching maximal values in areas whose depths range from 200 to 500 m. The highest mean abundance values occurred between April and June. The higher estimated abundance of C. hippurus in this period off the state of Rio Grande do Norte and within the 200-500 m depth range may be related to a migration pattern of food sources, as its main prey, the flying fish Hirundichthys affinis, uses floating algae as refuge and to deposit its pelagic eggs.

  1. Filamentous fungi vectored by ants (Hymenoptera: Formicidae) in a public hospital in North-Eastern Brazil.

    Science.gov (United States)

    Aquino, R S S; Silveira, S S; Pessoa, W F B; Rodrigues, A; Andrioli, J L; Delabie, J H C; Fontana, R

    2013-03-01

    The increase in opportunistic fungal infections has led to the search for putative sources of contamination in hospital environments. Ants in a public hospital in Itabuna, north-eastern Brazil were examined for carriage of filamentous fungi. During a year-long survey, ants from different hospital areas were sampled. Preference was given to locations where it was possible to observe ants actively foraging. The fungi found on the ants' integument were cultured and identified. A total of 106 ant workers belonging to 12 species in 11 genera were collected. A total of 47 fungal strains was isolated from 40% of the ants (N = 42). We found 16 fungal species in 13 genera associated with the ant workers. The prevalent fungal genera were Aspergillus, Purpureocillium and Fusarium. The ants Tapinoma melanocephalum, Paratrechina longicornis and Pheidole megacephala were associated with six fungal genera; and four genera of fungi were associated with Solenopsis saevissima workers. Fungal diversity was higher in the following hospital areas: nursery, hospital beds, breastmilk bank and paediatrics. Ants act as carriers of soil and airborne fungal species, and ant control in hospital areas is necessary to prevent the dissemination of such micro-organisms. Copyright © 2012 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  2. Clutch size in populations and species of cnemidophorines (Squamata: Teiidae on the eastern coast of Brazil

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    VANDERLAINE A. MENEZES

    2014-06-01

    Full Text Available We analyzed some reproductive aspects of 16 coastal populations, belonging to five lizard species (A. ocellifera, A. abaetensis, A. nativo, A. littoralis and C. lacertoides from different restinga habitats along the eastern coast of Brazil. This study aimed to evaluate to what extent the reproductive aspects vary geographically and among species. For each female, we recorded the number of vitellogenic follicles, size and color of the largest follicle, presence and size of corpora lutea, and number and size of oviductal eggs. Clutch size of almost all coastal populations/species of Ameivula had little variation and most clutches were composed of two eggs. There was a significant relationship between female size and the mean clutch size when females from different species were pooled. Mean egg volume, among species, varied from 420 to 655 mm3. Relative clutch mass varied from 0.129 to 0.159 and did not differ significantly among species. We concluded that the five coastal species studied (four bisexuals and one parthenogenetic had similar reproductive characteristics. Most of them presented multiple clutches, low clutch size and low relative clutch mass, similar to other species in the genus and to unisexual and bisexual species of the Teiidae family.

  3. A fossil loricariid catfish (Siluriformes: Loricarioidea from the Taubaté Basin, eastern Brazil

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    Maria Claudia Malabarba

    Full Text Available A new loricariid catfish is described from the Tremembé Formation (Late Oligocene to Early Miocene sediments of the Taubaté Basin in eastern São Paulo State, Brazil. Taubateia paraiba, new genus and species, is based on a single specimen preserved as a ventral-side impression of an articulated partial neurocranium, dorsal elements of the pectoral girdle and anterior vertebrae. The fossil is identified as belonging to family Loricariidae based on obvious overall similarity and the presence of diagnostic derived characters such as: odontodes, dorsal margin of metapterygoid contacting lateral ethmoid, presence of mesethmoid disk (condyle, and compound pterotic-supracleithrum bone. Also, as in most loricariids, the ossified transcapular (Baudelot's ligament plus basiocciptal lateral process form a prominent transverse wall at the occiput. Other derived characters preserved in Taubateia are synapomorphies at different levels within Loricariidae, including a wide and low parasphenoid, form of pterotic-supracleithrum, shape and position of the mesethmoid disk, a triangular lateral ethmoid with expanded posterolateral corner and a rounded and low ridge articulating with the metapterygoid, and a pointed distal margin of transverse process of the Weberian compound centrum. The derived characters recognized in this fossil are a distinctive combination for diagnosing a new genus and species but not for its unambiguous placements in any of the currently recognized loricariid subfamilies.

  4. Digital terrain analysis and long-term relief evolution of central-eastern Brazil

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    Carlos Henrique Grohmann

    2012-08-01

    Full Text Available Geomorphological theories for long-term relief evolution postulate the existence of planation surfaces, created by the continuouswork of erosion/deposition during periods of tectonic quiescence and recognized as extensive areas of very gentlerelief disturbed only locally by residual elevations, or by the apparent leveling of summit heights in a given region. Afterdecades since the publication of the main theories on landform evolution, the validity of these models is still an open discussion.In this paper, we present studies about the compartmentalization of landform elements, on a regional-scale basis,of central-eastern Brazil. The methods involved Digital Terrain Analysis in Geographic Information Systems, aiming theextraction and characterization of topographic variables and the compilation and mathematical analysis of geophysical andthermochronological data. Results were interpreted according to the geological context and the theories for long-term reliefevolution. The integration of morphometric, thermochronological and geophysical data does not support the validity of usingplanation surfaces in regional stratigraphic correlations.

  5. Paleoproterozoic high-sulfidation mineralization in the Tapajós gold province, Amazonian Craton, Brazil: geology, mineralogy, alunite argon age, and stable-isotope constraints

    Science.gov (United States)

    Juliani, Caetano; Rye, Robert O.; Nunes, Carmen M.D.; Snee, Lawrence W.; Correa, Rafael H.; Monteiro, Lena V.S.; Bettencourt, Jorge S.; Neumann, Rainer; Neto, Arnaldo A.

    2005-01-01

    The Brazilian Tapajós gold province contains the first evidence of high-sulfidation gold mineralization in the Amazonian Craton. The mineralization appears to be in large nested calderas. The Tapajós–Parima (or Ventuari–Tapajós) geological province consists of a metamorphic, igneous, and sedimentary sequence formed during a 2.10 to 1.87 Ga ocean−continent orogeny. The high-sulfidation mineralization with magmatic-hydrothermal alunite is related to hydrothermal breccias hosted in a rhyolitic volcanic ring complex that contains granitic stocks ranging in age from 1.89 to 1.87 Ga. Cone-shaped hydrothermal breccias, which flare upward, contain vuggy silica and have an overlying brecciated cap of massive silica; the deposits are located in the uppermost part of a ring-structure volcanic cone. Drill cores of one of the hydrothermal breccias contain alunite, natroalunite, pyrophyllite, andalusite, quartz, rutile, diaspore, woodhouseite–svanbergite, kaolinite, and pyrite along with inclusions of enargite–luzonite, chalcopyrite, bornite, and covellite. The siliceous core of this alteration center is surrounded by advanced argillic and argillic alteration zones that grade outward into large areas of propylitically altered rocks with sericitic alteration assemblages at depth. Several occurrences and generations of alunite are observed. Alunite is disseminated in the advanced argillic haloes that envelop massive and vuggy silica or that underlie the brecciated silica cap. Coarse-grained alunite also occurs in branching veins and locally is partly replaced by a later generation of fine-grained alunite. Silicified hydrothermal breccias associated with the alunite contain an estimated reserve of 30 tonnes of gold in rock that grades up to 4.5 g t−1 Au. Seven alunite samples gave 40Ar/39Ar ages of 1.869 to 1.846 Ga, with various degrees of apparent minor Ar loss. Stable isotopic data require a magmatic-hydrothermal origin for the alunite, typical for high

  6. Thermal structure of the Poraquê lake, Central Amazonian, Brazil = Estrutura térmica do lago Poraquê, Amazônia Central, Brasil

    Directory of Open Access Journals (Sweden)

    Fabio Marques Aprile

    2011-04-01

    Full Text Available Thermal gradient of a Central Amazonian lake was studied to establish a link between seasonal variations in the water level, temperature, suspended particulate matter (SPM and thermal stratification. Bimonthly measurements of temperature and PAR radiation were made at 0.25 m intervals from the surface to bottom from February 2004 to July 2006. Daily occurs full vertical mixing of the water column, and classic thermal stratification was not observed in the period. The effect of the winds associated to flood-pulse and the penetrativeconvection, transported the turbulent kinetic energy (TKE into the lake mixing the column of water. This phenomenon was more expressive in the rainfall seasons when is generally higher contributing to the circulation of the water. The limit of the euphotic zone ranged from 1.36 to 1.77 m in the period studied. The results of the transmission curves for the sampling sites showed that, in general, less than 0.01% of the surface light reached the bottom. The trend curve developed can facilitate the understanding of the limnological and ecological processes in lentic systems of whitewaters of the Central Amazonian.Foi estudado o gradiente térmico de um lago da Amazônia Central para estabelecer associação entre variações sazonais no nível de água, temperatura, material em suspensão e estratificação térmica. Bimestralmente, foram medidas a temperatura e a radiação luminosada superfície ao fundo do lago no período entre fevereiro de 2004 e julho de 2006. Ocorreu completa mistura vertical diária da coluna de água, não sendo observada estratificação térmica clássica no período. A energia cinética turbulenta (ECT proveniente da ação dos ventos em associação com o pulso de inundação foi responsável pela mistura da coluna de água. Esse fenômeno foi mais expressivo no período chuvoso, quando a ECT é geralmente mais alta, contribuindo para a circulação da água. A extensão da zona euf

  7. Population genetic structure of two columnar cacti with a patchy distribution in eastern Brazil.

    Science.gov (United States)

    Moraes, Evandro M; Abreu, Aluana G; Andrade, Sónia C S; Sene, Fabio M; Solferini, Vera N

    2005-11-01

    The genetic variability and population genetic structure of six populations of Praecereus euchlorus and Pilosocereus machrisii were investigated. The genetic variability in single populations of Pilosocereus vilaboensis, Pilosocereus aureispinus, and Facheiroa squamosa was also examined. All of these cacti species have a patchy geographic distribution in which they are restricted to small areas of xeric habitats in eastern Brazil. An analysis of genetic structure was used to gain insights into the historical mechanisms responsible for the patchy distribution of P. euchlorus and P. machrisii. High genetic variability was found at the populational level in all species (P=58.9-92.8%, A(p)=2.34-3.33, H(e)=0.266-0.401), and did not support our expectations of low variability based on the small population size. Substantial inbreeding was detected within populations (F(IS)=0.370-0.623). In agreement with their insular distribution patterns, P. euchlorus and P. machrisii had a high genetic differentiation (F(ST)=0.484 and F(ST)=0.281, respectively), with no evidence of isolation by distance. Accordingly, estimates of gene flow (N(m)) calculated from F(ST) and private alleles were below the level of N(m)=1 in P. machrisii and P. euchlorus. These results favored historical fragmentation as the mechanism responsible for the patchy distribution of these two species. The genetic distance between P. machrisii and P. vilaboensis was not compatible with their taxonomic distinction, indicating a possible local speciation event in this genus, or the occurrence of introgression events.

  8. Evaluating SAR polarization modes at L-band for forest classification purposes in Eastern Amazon, Brazil

    Science.gov (United States)

    Liesenberg, Veraldo; Gloaguen, Richard

    2013-04-01

    Single, interferometric dual, and quad-polarization mode data were evaluated for the characterization and classification of seven land use classes in an area with shifting cultivation practices located in the Eastern Amazon (Brazil). The Advanced Land-Observing Satellite (ALOS) Phased Array L-band Synthetic Aperture Radar (PALSAR) data were acquired during a six month interval. A clear-sky Landsat-5/TM image acquired at the same period was used as additional ground reference and as ancillary input data in the classification scheme. We evaluated backscattering intensity, polarimetric features, interferometric coherence and texture parameters for classification purposes using support vector machines (SVM) and feature selection. Results showed that the forest classes were characterized by low temporal backscattering intensity variability, low coherence and high entropy. Quad polarization mode performed better than dual and single polarizations but overall accuracies remain low and were affected by precipitation events on the date and prior SAR date acquisition. Misclassifications were reduced by integrating Landsat data and an overall accuracy of 85% was attained. The integration of Landsat to both quad and dual polarization modes showed similarity at the 5% significance level. SVM was not affected by SAR dimensionality and feature selection technique reveals that co-polarized channels as well as SAR derived parameters such as Alpha-Entropy decomposition were important ranked features after Landsat' near-infrared and green bands. We show that in absence of Landsat data, polarimetric features extracted from quad-polarization L-band increase classification accuracies when compared to single and dual polarization alone. We argue that the joint analysis of SAR and their derived parameters with optical data performs even better and thus encourage the further development of joint techniques under the Reducing Emissions from Deforestation and Degradation (REDD) mechanism.

  9. Assessment of the trophic status of four coastal lagoons and one estuarine delta, eastern Brazil.

    Science.gov (United States)

    Cotovicz Junior, Luiz Carlos; Brandini, Nilva; Knoppers, Bastiaan Adriaan; Mizerkowski, Byanka Damian; Sterza, José Mauro; Ovalle, Alvaro Ramon Coelho; Medeiros, Paulo Ricardo Petter

    2013-04-01

    Anthropogenic eutrophication of aquatic ecosystems continues to be one of the major environmental issues worldwide and also of Brazil. Over the last five decades, several approaches have been proposed to discern the trophic state and the natural and cultural processes involved in eutrophication, including the multi-parameter Assessment of Estuarine Trophic Status (ASSETS) index model. This study applies ASSETS to four Brazilian lagoons (Mundaú, Manguaba, Guarapina, and Piratininga) and one estuarine delta (Paraíba do Sul River), set along the eastern Brazilian coast. The model combines three indices based on the pressure-state-response (PSR) approach to rank the trophic status and forecast the potential eutrophication of a system, to which a final ASSETS grade is established. The lagoons were classified as being eutrophic and highly susceptible to eutrophication, due primarily to their longer residence times but also their high nutrient input index. ASSETS classified the estuary of the Paraíba do Sul river with a low to moderate trophic state (e.g., largely mesotrophic) and low susceptibility to eutrophication. Its nutrient input index was high, but the natural high dilution and flushing potential driven by river flow mitigated the susceptibility to eutrophication. Eutrophication forecasting provided more favorable trends for the Mundaú and Manguaba lagoons and the Paraíba do Sul estuary, in view of the larger investments in wastewater treatment and remediation plans. The final ASSETS ranking system established the lagoons of Mundaú as "moderate," Manguaba as "bad," Guarapina as "poor," and Piratininga as "bad," whereas the Paraíba do Sul River Estuary was "good."

  10. Surface thermal perturbations of the recent past at low latitudes – inferences based on borehole temperature data from Eastern Brazil

    Directory of Open Access Journals (Sweden)

    L. C. C. Benyosef

    2007-08-01

    Full Text Available Borehole temperature data from the eastern parts of Brazil has been examined in an attempt to extract information on surface thermal perturbations of the recent past at low latitudes. Forward models were employed in the analysis of temperature logs from 17 localities and, in addition, Bayesian inverse modeling was carried out for data from 14 selected sites. The model results have allowed determination of the magnitude as well as the duration of ground surface temperature (GST changes in three major geographic zones of Brazil. Prominent among such changes are the warming episodes that occurred over much of the subtropical highland regions in the southeastern parts of Brazil. The present magnitude of GST changes in this region are in the range of 2 to 3.5°C but have had their beginning during the early decades of the 20th century. Nearly similar trends are also seen in temperature-depth profiles of bore holes in the subtropical humid zones of the interior and coastal areas of southern Brazil. The data from semi arid zones of northeast Brazil also indicate occurrence of surface warming events but the magnitudes are in the range of 1.4 to 2.2°C while the duration of the warming event is larger, extending back into the last decades of the 19th century. There are indications that changes in both climate and vegetation cover contribute to variations in GST. Thus the magnitudes of GST variations are relatively large in localities which have undergone changes in vegetation cover. Also there are indications that GST changes are practically insignificant in areas of tropical rain forest. Another important result emerging from model studies is that the climate was relatively cooler during the 17th and 18th centuries. The climate histories, deduced from geothermal data, are found to be consistent with results of available meteorological records in southern Brazil. Comparative studies also indicate that the magnitudes and duration of recent climate changes

  11. Surface thermal perturbations of the recent past at low latitudes – inferences based on borehole temperature data from Eastern Brazil

    Directory of Open Access Journals (Sweden)

    L. C. C. Benyosef

    2007-03-01

    Full Text Available Borehole temperature data from the eastern parts of Brazil has been examined in an attempt to extract information on surface thermal perturbations of the recent past at low latitudes. Forward models were employed in the analysis of temperature logs from 16 localities and, in addition, inverse modeling was carried out for data from 10 selected sites. The model results have allowed determination of the magnitude as well as the duration of ground surface temperature (GST changes in three major geographic zones of Brazil. Prominent among such events are the warming episodes that occurred over much of the subtropical highland regions in the southeastern parts of Brazil. The present magnitude of GST changes in this region are in the range of 2 to 3.5°C but have had their beginning during the early decades of the 20th century. Nearly similar trends are also seen in temperature-depth profiles of bore holes in the subtropical humid zones of the interior and coastal areas of southern Brazil. The data from semi arid zones of northeast Brazil also indicate occurrence of surface warming events but the magnitudes are in the range of 1.4 to 2.2°C while the duration of the warming event is larger, extending back into the last decades of the 19th century. There are indications that changes in both climate and vegetation cover contribute to variations in GST. Thus the magnitudes of GST variations are relatively large in localities which have undergone changes in vegetation cover. Also there are indications that GST changes are practically insignificant in areas of tropical rain forest. Another important result emerging from model studies is that the climate was relatively cooler during the 17th and 18th centuries. The climate histories, deduced from geothermal data, are found to be consistent with results of available meteorological records in southern Brazil. Comparative studies also indicate that the magnitudes and duration of recent climate changes in

  12. Contributions to the petrography, geochemistry and geochronology (U-Pb and Sm-Nd) of the Paleoproterozoic effusive rocks from Iricoume Group, Amazonian Craton, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Marques, Suelen Nonata de Souza; Nascimento, Rielva Solimairy Campelo do, E-mail: suelen-marques@hotmail.com, E-mail: rielva@ufam.edu.br [Universidade Federal do Amazonas (UFAM), Manaus, AM (Brazil). Inst. de Geociencias; Souza, Valmir da Silva; Dantas, Elton Luiz, E-mail: vsouza@unb.br, E-mail: elton@unb.br [Universidade de Brasilia (UnB), DF (Brazil). Inst. de Geociencias; Valerio, Cristovao da Silva, E-mail: cristovao@igeo.ufrr.br [Universidade Federal de Roraima (UFRR), Boa Vista, RR (Brazil). Inst. de Geociencias

    2014-07-01

    The southernmost region of the Guyana shield, Amazonian craton, hosts large record of Paleoproterozoic effusive rocks of the Iricoume Group. They present remarkably well-preserved igneous textures and structures. The SiO{sub 2} contents reveal a bimodal association marked by a compositional gap between acid (SiO{sub 2} > 67 wt%) and intermediate (SiO{sub 2} < 57.7 wt%) rocks. The acid effusive rocks are rhyolites to rhyodacites with high SiO{sub 2}, alkali, Rb, Zr, Nb + Ta, La + Ce and 104 Ga/Al content and low Fe{sub 2}O{sub 3tot}, TiO{sub 2}, CaO, Sr and Co content. They exhibit subalkaline, metaluminous-to-peraluminous compositions, and geochemically compatible to A-type magmatism emplaced in post-collisional to within-plate tectonic settings. The intermediate rocks are andesitic/basalt to andesite relatively high contents of TiO{sub 2}, Al{sub 2}O{sub 3}, Fe{sub 2}O{sub 3total}, MgO, CaO, Sr and Co; low SiO{sub 2}, K{sub 2}O, Rb, Zr, Nb + Ta, La + Ce. They have subalkaline and metaluminous geochemical composition and plot on within-plate basalt field. The acid rocks crystallized at 1882 ± 11 Ma in U-Pb analyses for LA-MC-ICPMS zircon data. The Sm-Nd isotopic data on all rocks reveal a Nd TDM model ages between 2.59 and 2.16 Ga and ε{sub Nd}(t) values between -5.78 and 0.03, indicate that the magmatic evolution was related to the reworking of older Paleoproterozoic at the Rhyacian-Siderian period, continental crust (Transamazonian crust-forming event) with some mixing with a limited amount mantle-derived magmas or with contamination by Archean crust. The petrographic, geochemical and geochronological data presented in this paper suggest a within-plate to post-collisional tectonic setting for the Iricoume volcanism, involving lower crust uplift and generation of basalt magma in an extensional regime. (author)

  13. The structure of the Amazonian craton: Available geophysical evidence

    Science.gov (United States)

    Rosa, João Willy Corrêa; Rosa, José Wilson Corrêa; Fuck, Reinhardt A.

    2016-10-01

    The Amazonian craton, which covers a large area of South America, and is thought to have been stable since the end of the Mesoproterozoic, has recently benefited from a series of regional geophysical surveys. The Amazonian craton comprises the northern Guyana shield and the southern Central Brazil shield. It has become the main subject of seismological studies aiming to determine crustal thickness. Moho thickness maps that cover a large part of the South American continent summarize these studies. Receiver function studies, aided by surface wave dispersion tomography, were also useful tools applied in the region over the past decade. These have been improved by the addition of temporary and permanent regional seismological arrays and stations. An interesting NNW-SSE Moho depth anomaly, pointing to crustal thickening of up to 60 km in the central Guyana shield and a 50 km thick anomaly of the southern Central Brazil shield were recently identified. Areas with crustal thickening correspond to Paleoproterozoic magmatic arcs. The upper mantle seismic anisotropy in part of the region has been determined from SKS splitting studies. The currently available seismic anisotropy information shows that the orientation of the determined anisotropic axis is related to the frozen in anisotropy hypothesis for the Amazonian craton. The orientation of the anisotropic axis shows no relation to the current South American plate motion in the Amazonian craton. Most recently, detailed information for the two shields has benefited from a series of high-resolution, regional aerogeophysical surveys, made available by CPRM, the Brazilian Geological Survey. In addition to the mentioned contribution from seismology for imaging deeper crustal structures, regional gravity surveys have been expanded, adding to previous Bouguer anomaly maps, and deep drilling information from early exploration efforts have been compiled for the Amazon basin, which covers the Amazonian craton separating the Guyana

  14. Origin and Domestication of Native Amazonian Crops

    Directory of Open Access Journals (Sweden)

    Doriane Picanço-Rodrigues

    2010-01-01

    Full Text Available Molecular analyses are providing new elements to decipher the origin, domestication and dispersal of native Amazonian crops in an expanding archaeological context. Solid molecular data are available for manioc (Manihot esculenta, cacao (Theobroma cacao, pineapple (Ananas comosus, peach palm (Bactris gasipaes and guaraná (Paullinia cupana, while hot peppers (Capsicum spp., inga (Inga edulis, Brazil nut (Bertholletia excelsa and cupuassu (Theobroma grandiflorum are being studied. Emergent patterns include the relationships among domestication, antiquity (terminal Pleistocene to early Holocene, origin in the periphery, ample pre-Columbian dispersal and clear phylogeographic population structure for manioc, pineapple, peach palm and, perhaps, Capsicum peppers. Cacao represents the special case of an Amazonian species possibly brought into domestication in Mesoamerica, but close scrutiny of molecular data suggests that it may also have some incipiently domesticated populations in Amazonia. Another pattern includes the relationships among species with incipiently domesticated populations or very recently domesticated populations, rapid pre- or post-conquest dispersal and lack of phylogeographic population structure, e.g., Brazil nut, cupuassu and guaraná. These patterns contrast the peripheral origin of most species with domesticated populations with the subsequent concentration of their genetic resources in the center of the basin, along the major white water rivers where high pre-conquest population densities developed. Additional molecular genetic analyses on these and other species will allow better examination of these processes and will enable us to relate them to other historical ecological patterns in Amazonia.

  15. 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

    OpenAIRE

    Reis,Nelson Joaquim; Nadeau, Serge; Fraga,Leda Maria; BETIOLLO, Leandro Menezes; Faraco,Maria Telma Lins; Reece,Jimmy; Lachhman,Deokumar; Ault,Randy

    2017-01-01

    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 Mu...

  16. Effect of solar flare on the equatorial electrojet in eastern Brazil region

    Indian Academy of Sciences (India)

    R G Rastogi; P Janardhan; H Chandra; N B Trivedi; Vidal Erick

    2017-06-01

    The effect of solar flare, sudden commencement of magnetic storm and of the disturbances ring current on the equatorial electrojet in the Eastern Brazil region, where the ground magnetic declination is as large as 20∘W is studied based on geomagnetic data with one minute resolution from Bacabal during November–December 1990. It is shown that the mean diurnal vector of the horizontal field was aligned along 2∘E of north at Huancayo and 30∘W of north at Bacabal during the month of December 1990. Number of solar flares that occurred on 30 December 1990 indicated the direction of solar flare related $\\Delta H$ vector to be aligned along 5∘E of north at Huancayo and 28∘W of north at Bacabal. This is expected as the solar flare effects are due to the enhanced conductivity in the ionosphere. The SC at 2230 UT on 26 November 1990 produced a positive impulse in $\\Delta X$ and negative impulse in $\\Delta Y$ at Bacabal with $\\Delta H$ vector aligned along 27∘W of north. At Huancayo the $\\Delta H$ vector associated with SC is aligned along 8∘E of north, few degrees east to the alignment of the diurnal vector of H. The magnetic storm that followed the SC had a minimum Dst index of –150 nT. The corresponding storm time disturbance in $\\Delta X$ at Huancayo as well as at Bacabal were about –250 nT but $\\Delta Y$ at Bacabal was about +70 nT and very small at Huancayo, that give the alignment of the H vector due to ring current about 16∘W of north at Bacabal and almost along N–S at Huancayo. Thus alignment of the $\\Delta H$ vector due to ring current at Bacabal is 14∘E of the mean direction of $\\Delta H$ vector during December 1990. This is consistent with the direction of ring current dependent on the dipole declination at the ring current altitude which is about 5∘W of north over Bacabal and the deviation of declination due to the ring current during disturbed period given by the angle $(\\psi-D)$.

  17. Foucault’s Apparatuses of Sexuality and Alliance Confronted Empirically: The Social Construction of Sexuality of Adolescents Living in Poverty in an Amazonian City of Brazil

    Directory of Open Access Journals (Sweden)

    CINTIA MAURA JORGE SOARES

    2013-01-01

    Full Text Available The objective of this article was to identify the possible constructs of one or more apparatus of sexuality and of alliance in adolescents living in poverty in Brazil. The research methodology was a qualitative assessment using an ethnographic approach. The principal data collection technique, in addition to ethnographic observation and documentary analysis, was face-to-face in-depth interviews. Fourteen adolescents living in the same Belém neighbourhood were observed and interviewed, as well as their parents. The data analysis revealed an apparatus of sexuality as an apparatus of safe sex whereas an apparatus of alliance, according to Foucault, was described after analysis and confirmation of the data as an alliance of powerfulness. These results is bringing new light on the question of the social construct of sexuality among adolescents living in poverty, put into better position the use of Foucault’s concepts, considered till now only as philosophical abstractions, and not as empirical results.

  18. Physiological Response of Local and Saanen x Local Cross Goats during the Late Rainy Season in North-eastern Brazil

    Directory of Open Access Journals (Sweden)

    Degli, P.

    2004-01-01

    Full Text Available In order to compare in vivo performance and environmental adaptation of two genetic types of goats raised in north-eastern Brazil, 20 females (10 local and 10 Saanen x local were used in this experiment. During the late rainy season the goats were monitored for the following parameters: body weight, body (BT and skin temperature (ST, respiratory (RR and heart rate (HR as well as the air temperature (AT and humidity (HU in the pens in the morning (MR and afternoon (AR. From May to June the crossbred goats showed a significant gain (P< 0.05; the live weight of F1 was superior to the local goats (P< 0.05 at the end of the experiment. The physiological response during the AR was significantly superior to MR (P< 0.05 for all parameters. The local goats achieved the highest values of BT and ST during the experiment. On average, the physiological rhythms (RR and HR were higher in crossbred than local goats. In conclusion, crossbred goats showed to be less at risk to environmental stress condition in north-eastern Brazil.

  19. Reservoir storage and hydrologic responses to droughts in the Paraná River basin, south-eastern Brazil

    Science.gov (United States)

    Melo, Davi de C. D.; Scanlon, Bridget R.; Zhang, Zizhan; Wendland, Edson; Yin, Lei

    2016-11-01

    Droughts are particularly critical for Brazil because of impacts on water supply and because most (70 %) of its electricity is derived from hydroelectric generation. The Paraná basin (PB), a major hydroelectric producing region with 32 % (60 million people) of Brazil's population, recently experienced the most severe drought since the 1960s, compromising the water supply for 11 million people in São Paulo. The objective of this study is to quantify linkages between meteorological and hydrological droughts based on remote sensing, modelling, and monitoring data using the Paraná River basin in south-eastern Brazil as a case study. Two major meteorological droughts were identified in the early 2000s and 2014, with precipitation 20-50 % below the long-term mean. Total water storage change estimated from the Gravity Recovery and Climate Experiment (GRACE) satellites declined by 150 km3 between April 2011 and April 2015. Simulated soil moisture storage declined during the droughts, resulting in decreased runoff into reservoirs. As a result, reservoir storage decreased by 30 % relative to the system's maximum capacity, with negative trends ranging from 17 (May 1997-April 2001) to 25 km3 yr-1 (May 2011-April 2015). Storage in upstream reservoirs is mostly controlled by natural climate forcing, whereas storage in downstream reservoirs also reflects dam operations. This study emphasizes the importance of integrating remote sensing, modelling, and monitoring data to evaluate droughts and to establish a preliminary understanding of the linkages between a meteorological and hydrological drought for future management.

  20. Distribution of the CCR5delta32 allele (gene variant CCR5) in Rondônia, Western Amazonian region, Brazil

    Science.gov (United States)

    de Farias, Josileide Duarte; Santos, Marlene Guimarães; de França, Andonai Krauze; Delani, Daniel; Tada, Mauro Shugiro; Casseb, Almeida Andrade; Simões, Aguinaldo Luiz; Engracia, Vera

    2012-01-01

    Since around 1723, on the occasion of its initial colonization by Europeans, Rondonia has received successive waves of immigrants. This has been further swelled by individuals from northeastern Brazil, who began entering at the beginning of the twentieth century. The ethnic composition varies across the state according to the various sites of settlement of each wave of immigrants. We analyzed the frequency of the CCR5Δ32 allele of the CCR5 chemokine receptor, which is considered a Caucasian marker, in five sample sets from the population. Four were collected in Porto Velho, the state capital and the site of several waves of migration. Of these, two, from the Hospital de Base were comprised of HB Mothers and HB Newborns presenting allele frequencies of 3.5% and 3.1%, respectively, a third from the peri-urban neighborhoods of Candelária/Bate-Estaca (1.8%), whereas a fourth, from the Research Center on Tropical Medicine/CEPEM (0.6%), was composed of malaria patients under treament. The fifth sample (3.4%) came from the inland Quilombola village of Pedras Negras. Two homozygous individuals (CCR5Δ32/CCR5Δ32) were detected among the HB Mother samples. The frequency of this allele was heterogeneous and higher where the European inflow was more pronounced. The presence of the allele in Pedras Negras revealed European miscegenation in a community largely comprising Quilombolas. PMID:22481870

  1. Phlebotomines (Diptera: Psychodidae) in a Hydroelectric System Affected Area from Northern Amazonian Brazil: Further Insights into the Effects of Environmental Changes on Vector Ecology

    Science.gov (United States)

    Furtado, Nercy Virginia Rabelo; Galardo, Allan Kardec Ribeiro; Galardo, Clicia Denis; Firmino, Viviane Caetano

    2016-01-01

    During 2012–2015, an entomological survey was conducted as part of a phlebotomine (Diptera: Psychodidae) monitoring program in an area influenced by the Santo Antônio do Jari hydroelectric system (Amapá State, Brazil). The purpose was to study aspects of Amazon/Guianan American cutaneous leishmaniasis (ACL) vectors subjected to stresses by anthropogenic environmental changes. For sampling, CDC light traps were positioned 0.5, 1, and 20 m above ground at five capture locations along the Jari River Basin. Fluctuations in phlebotomine numbers were analyzed to determine any correlation with rainfall, dam waterlogging, and/or ACL cases, from May 2012 to March 2015. We captured 2,800 individuals, and among 45 species identified, Bichromomyia flaviscutellata, Nyssomyia umbratilis, and Psychodopygus squamiventris s.l. were determined to be the main putative vectors, based on current knowledge of the Amazon/Guianan ACL scenario. Rainfall, but not complete flooding, was relatively correlated with phlebotomine fluctuation, mainly observed for Ps. squamiventris s.l., as were ACL cases with Ny. umbratilis. Behavioral changes were observed in the unexpected high frequency of Bi. flaviscutellata among CDC captures and the noncanopy dominance of Ny. umbratilis, possibly attributable to environmental stress in the sampled ecotopes. Continuous entomological surveillance is necessary to monitor the outcomes of these findings. PMID:28042300

  2. Distribution of the CCR5delta32 allele (gene variant CCR5 in Rondônia, Western Amazonian region, Brazil

    Directory of Open Access Journals (Sweden)

    Josileide Duarte de Farias

    2012-01-01

    Full Text Available Since around 1723, on the occasion of its initial colonization by Europeans, Rondonia has received successive waves of immigrants. This has been further swelled by individuals from northeastern Brazil, who began entering at the beginning of the twentieth century. The ethnic composition varies across the state according to the various sites of settlement of each wave of immigrants. We analyzed the frequency of the CCR5L32 allele of the CCR5 chemokine receptor, which is considered a Caucasian marker, in five sample sets from the population. Four were collected in Porto Velho, the state capital and the site of several waves of migration. Of these, two, from the Hospital de Base were comprised of HB Mothers and HB Newborns presenting allele frequencies of 3.5% and 3.1%, respectively, a third from the peri-urban neighborhoods of Candelária/Bate-Estaca (1.8%, whereas a fourth, from the Research Center on Tropical Medicine/CEPEM (0.6%, was composed of malaria patients under treament. The fifth sample (3.4% came from the inland Quilombola village of Pedras Negras. Two homozygous individuals (CCR5Δ32/CCR5Δ32 were detected among the HB Mother samples. The frequency of this allele was heterogeneous and higher where the European inflow was more pronounced. The presence of the allele in Pedras Negras revealed European miscegenation in a community largely comprising Quilombolas.

  3. 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.

  4. Feeding ecology of Lutjanus analis (Teleostei: Lutjanidae from Abrolhos Bank, Eastern Brazil

    Directory of Open Access Journals (Sweden)

    Matheus Oliveira Freitas

    2011-06-01

    Full Text Available Diet and feeding ecology of the mutton snapper Lutjanus analis were investigated in the Abrolhos Bank, Eastern Brazil, the largest and richest coral reefs in the South Atlantic, where about 270 species of reef and shore fishes occur. To evaluate seasonal and ontogenetic shifts in the diet, specimens of L. analis were obtained through a fish monitoring program in four cities in southern Bahia State, from June 2005 to March 2007. Stomachs from 85 mutton snappers that ranged in size from 18.1 to 74.0 cm TL were examined. Prey were identified to the lowest possible taxon and assessed by the frequency of occurrence and volumetric methods. Variations in volume prey consumption were evaluated using non-metric multi-dimensional scaling ordination, analysis of similarity, and similarity percentage methods. Significant differences in diet composition among size classes were registered, whereas non significant differences between seasons were observed. Considering size-classes, food items consumption showed important variations: juveniles (50.1 cm TL consumed basically fish, mostly Anguiliformes. Lutjanus analis is an important generalist reef predator, with a broad array of food resources and ontogenetic changes in the diet. This snapper species plays an important role on the trophic ecology of the Abrolhos Bank coral reefs.Foram avaliadas a dieta e a ecologia alimentar da cioba Lutjanus analis no Banco dos Abrolhos, Leste do Brasil. O Banco dos Abrolhos abrange os maiores e mais diversos recifes de corais do Atlântico Sul, onde cerca de 270 espécies de peixes recifais e costeiros ocorrem. Para a avaliação das variações sazonais e ontogênicas na dieta, exemplares de L. analis foram obtidos através de um programa de monitoramento em quatro cidades do extremo sul da Bahia, entre junho de 2005 e março de 2007. Estômagos de 85 exemplares com comprimento total variando entre 18,1 e 74,0 cm foram examinados. Os itens alimentares foram identificados at

  5. Records of new localities and hosts for crustacean parasites in fish from the eastern Amazon in northern Brazil.

    Science.gov (United States)

    Oliveira, Marcos Sidney Brito; Corrêa, Lincoln Lima; Oliveira Ferreira, Drielly; Neves, Lígia Rigor; Tavares-Dias, Marcos

    2017-06-01

    The aim of this study was to investigate parasites crustacean fauna in Arapaima gigas, Cichla monoculus, Cichla ocellaris, Cichla jariina, Satanoperca jurupari, Leporinus friderici, Leporinus fasciatus, Hoplias malabaricus, Phractocephalus hemioliopterus, Serrasalmus altispinis, Pseudoplatystoma tigrinum and Potamotrygon motoro of the State Amapá and Pará, in northern Brazil. A total of 242 parasites, including Argulus elongatus, Argulus multicolor,Argulus juparanaensis, Argulus nattereri, Dolops discoidalis, Dolops longicauda, Braga patagonica, Braga fluviatilis, Livoneca guianensis and undetermined Lernaeidae, were collected from these hosts. The Argulus species had the greatest richness among the community of parasitic crustaceans. There was a low abundance of parasites among the hosts, other than D. discoidalis, was most abundant in the integument of A. gigas and P. tigrinum. Finally, the present study reported nine new hosts for the crustacean parasite species and expanded knowledge of the occurrence of some parasite species in the Jari River basin, in eastern Amazon.

  6. Sympatric and allopatric combinations of Lymnaea columella and Fasciola hepatica from southern and south-eastern Brazil.

    Science.gov (United States)

    Coelho, L H L; Lima, W S; Guimaraes, M P

    2009-09-01

    Experimental infections of Lymnaea columella with Fasciola hepatica were carried out to test the effect of sympatric and allopatric combinations between parasite and host, by using snails and flukes from southern and south-eastern Brazil. Four groups of 50 snails were infected with four miracidia per snail: two groups in sympatric and two groups in allopatric combinations. Sympatric combinations between parasite and host were more efficient than allopatric ones when snails from Itajubá were used, but the opposite was observed in infections involving snails from Pelotas. The sympatric association between L. columella and F. hepatica from Itajubá was significantly higher than in the other combinations. We concluded that the host-parasite relationship between L. columnella and F. hepatica may vary according to the geographical origin of the snails and flukes involved.

  7. Deciphering the depositional environment of the laminated Crato fossil beds (Early Cretaceous, Araripe Basin, North-eastern Brazil)

    DEFF Research Database (Denmark)

    Heimhofer, Ulrich; Ariztegui, Daniel; Lenniger, Marc

    2010-01-01

    The laminated limestones of the Early Cretaceous Crato Formation of the Araripe Basin (North-eastern Brazil) are world-famous for their exceptionally well-preserved and taxonomically diverse fossil fauna and flora. Whereas the fossil biota has received considerable attention, only a few studies...... bedded, pale to dark lamination. To obtain information on palaeoenvironmental conditions, sample slabs derived from three local stratigraphic sections within the Araripe Basin were studied using high-resolution multiproxy techniques including detailed logging, petrography, mu-XRF scanning and stable......-poor meteoric water source and support a continental freshwater setting for the Nova Olinda Member. The delta C-13 values, which are comparatively rich in C-13 (between -0.1 and +1.9 parts per thousand), are interpreted to reflect reduced throughflow of water in a restricted basin, promoting...

  8. Disseminated histoplasmosis in HIV-infected patients: determinants of relapse and mortality in a north-eastern area of Brazil.

    Science.gov (United States)

    Damasceno, Lisandra Serra; Ramos, Alberto Novaes; Alencar, Carlos Henrique; Gonçalves, Maria Vânia Freitas; de Mesquita, Jacó Ricarte Lima; Soares, Anne Taumaturgo Dias; Coutinho, Anna Gisele Nunes; Dantas, Carolina Cavalcante; Leitão, Terezinha do Menino Jesus Silva

    2014-07-01

    Many relapses and deaths resulting from disseminated histoplasmosis (DH) in acquired immunodeficiency syndrome (AIDS) patients have been observed in an endemic area in north-eastern Brazil. The objective of this study was to evaluate the risk factors associated with the clinical outcomes of DH/AIDS coinfection in patients from the state of Ceará, Brazil. A retrospective cohort of AIDS patients, after their hospital discharge due to first DH episode in the period 2002-2008, was followed until December 31, 2010, to investigate the factors associated with relapse and mortality. A total of 145 patients were evaluated in the study. Thirty patients (23.3%) relapsed and the overall mortality was 30.2%. The following variables were significantly (P histoplasmosis relapse was also significantly associated with mortality. In the multivariate analysis, non-adherence to HAART was the independent risk factor that was associated with both relapse (Adj OR = 6.28) and overall mortality (Adj OR = 8.03); efavirenz usage was discovered to be significant only for the overall mortality rate (Adj OR = 4.50). Adherence to HAART was the most important variable that influenced the outcomes in this specific population.

  9. An isolate of the nematophagous fungus Monacrosporium thaumasium for the control of cattle trichostrongyles in south-eastern Brazil.

    Science.gov (United States)

    Assis, R C L; Luns, F D; de Araújo, J V; Braga, F R; Assis, R L; Marcelino, J; Freitas, P C; Andrade, M A

    2015-03-01

    A mycelial formulation in sodium alginate pellets of the nematophagous fungus Monacrosporium thaumasium (isolate NF34A) was assessed in the biological control of beef cattle trichostrongyles in tropical Brazil. Two groups of ten male Nellore calves aged 6 months, a fungus-treated group and a control group, were fed on a pasture of Brachiaria decumbens naturally infected with larvae of cattle trichostrongyles. The fungus-treated group received doses of sodium alginate mycelial pellets orally (1 g pellets (0.2 g fungus)/10 kg live weight) twice a week for 12 months. At the end of the study there was a significant reduction (Pcontrol group. There was a 47.3% reduction in herbage samples, collected up to 0-20 cm from faecal pats, between the fungus-treated and control groups, and a 58% reduction when the sampling distance was 20-40 cm from faecal pats (Pnematode-trapping fungus M. thaumasium reduced trichostrongyles in tropical south-eastern Brazil and could be an effective tool for the biological control of this parasitic nematode in beef cattle. However, in such a tropical climate with low rainfall the fungal viability can be reduced.

  10. Molecular characterisation of Bartonella species in cats from São Luís, state of Maranhão, north-eastern Brazil

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    Maria do Socorro Costa de Oliveira Braga

    2012-09-01

    Full Text Available Bartonella species are fastidious bacteria that predominantly infect mammalian erythrocytes and endothelial cells and cause long-lasting bacteraemia in their reservoir hosts. Reports that describe the epidemiology of bartonellosis in Brazil are limited. This study aimed to detect and characterise Bartonella spp DNA from cat blood samples in São Luís, Maranhão, north-eastern Brazil. Among 200 cats tested for multiple genes, nine (4.5% were positive for Bartonella spp: six cats for Bartonella henselae and three for Bartonella clarridgeiae. Based on the phylogenetic analysis of four genes, the B. henselae strain matched strains previously observed in Brazil and was positioned in the same clade as B. henselae isolates from the United States of America. Moreover, sequence alignment demonstrated that the B. clarridgeiae strain detected in the present study was the same as the one recently detected in cats from southern Brazil.

  11. Molecular characterisation of Bartonella species in cats from São Luís, state of Maranhão, north-eastern Brazil.

    Science.gov (United States)

    Braga, Maria do Socorro Costa de Oliveira; Diniz, Pedro Paulo Vissotto de Paiva; André, Marcos Rogério; Bortoli, Caroline Plácidi de; Machado, Rosangela Zacarias

    2012-09-01

    Bartonella species are fastidious bacteria that predominantly infect mammalian erythrocytes and endothelial cells and cause long-lasting bacteraemia in their reservoir hosts. Reports that describe the epidemiology of bartonellosis in Brazil are limited. This study aimed to detect and characterise Bartonella spp DNA from cat blood samples in São Luís, Maranhão, north-eastern Brazil. Among 200 cats tested for multiple genes, nine (4.5%) were positive for Bartonella spp: six cats for Bartonella henselae and three for Bartonella clarridgeiae. Based on the phylogenetic analysis of four genes, the B. henselae strain matched strains previously observed in Brazil and was positioned in the same clade as B. henselae isolates from the United States of America. Moreover, sequence alignment demonstrated that the B. clarridgeiae strain detected in the present study was the same as the one recently detected in cats from southern Brazil.

  12. Temporal Decay in Timber Species Composition and Value in Amazonian Logging Concessions

    Science.gov (United States)

    Peres, Carlos A.

    2016-01-01

    Throughout human history, slow-renewal biological resource populations have been predictably overexploited, often to the point of economic extinction. We assess whether and how this has occurred with timber resources in the Brazilian Amazon. The asynchronous advance of industrial-scale logging frontiers has left regional-scale forest landscapes with varying histories of logging. Initial harvests in unlogged forests can be highly selective, targeting slow-growing, high-grade, shade-tolerant hardwood species, while later harvests tend to focus on fast-growing, light-wooded, long-lived pioneer trees. Brazil accounts for 85% of all native neotropical forest roundlog production, and the State of Pará for almost half of all timber production in Brazilian Amazonia, the largest old-growth tropical timber reserve controlled by any country. Yet the degree to which timber harvests beyond the first-cut can be financially profitable or demographically sustainable remains poorly understood. Here, we use data on legally planned logging of ~17.3 million cubic meters of timber across 314 species extracted from 824 authorized harvest areas in private and community-owned forests, 446 of which reported volumetric composition data by timber species. We document patterns of timber extraction by volume, species composition, and monetary value along aging eastern Amazonian logging frontiers, which are then explained on the basis of historical and environmental variables. Generalized linear models indicate that relatively recent logging operations farthest from heavy-traffic roads are the most selective, concentrating gross revenues on few high-value species. We find no evidence that the post-logging timber species composition and total value of forest stands recovers beyond the first-cut, suggesting that the commercially most valuable timber species become predictably rare or economically extinct in old logging frontiers. In avoiding even more destructive land-use patterns, managing

  13. Climate science: The resilience of Amazonian forests

    Science.gov (United States)

    Bush, Mark B.

    2017-01-01

    Isotope evidence suggests that, during dry periods associated with the most recent ice age, the Amazonian forest survived in a region that is sensitive to rainfall changes -- settling a debate about Amazonian aridity. See Letter p.204

  14. Multiple Determinants of Anuran Richness and Occurrence in an Agricultural Region in South-Eastern Brazil

    Science.gov (United States)

    Prado, Vitor H. M.; Rossa-Feres, Denise de C.

    2014-04-01

    In agricultural landscapes, studies that identify factors driving species richness and occupancy are important because they can guide farmers to use conservation practices that minimize species loss. In this context, anurans are threatened by habitat loss because they depend on the characteristics of both local water bodies and adjacent landscapes. We used a model selection approach to evaluate the influence of local and landscape variables in determining anuran species richness and occurrence in 40 freshwater bodies in a heavily deforested region of semideciduous Atlantic Forest in southeastern Brazil. Our aim was to develop recommendations for conservation of anuran communities in rural areas. Pond hydroperiod and area were the most important variables for explaining anuran species richness and occupancy, with greatest species richness being found in water bodies with intermediate hydroperiod and area. Other important variables that reflected individual species occupancies were the number of vegetation types and pond isolation. In addition, recent studies evidenced that water bodies near forest fragments have higher anuran abundance or diversity. In conclusion, we suggest the maintenance of semi-permanent ponds, isolated from large rivers or reservoirs and near forest fragments, as an effective strategy to conserve anuran fauna in agricultural landscapes of southeastern Brazil. Brazilian government requires the maintenance of forests as legal reserve in each farm, and farmers need to maintain ponds as drinking water for cattle or crop irrigation. For this reason, the guidelines suggested in the present study can be easily adopted, without additional costs to rural productivity.

  15. Millennial-scale dynamics of southern Amazonian rain forests.

    Science.gov (United States)

    Mayle, F E; Burbridge, R; Killeen, T J

    2000-12-22

    Amazonian rain forest-savanna boundaries are highly sensitive to climatic change and may also play an important role in rain forest speciation. However, their dynamics over millennial time scales are poorly understood. Here, we present late Quaternary pollen records from the southern margin of Amazonia, which show that the humid evergreen rain forests of eastern Bolivia have been expanding southward over the past 3000 years and that their present-day limit represents the southernmost extent of Amazonian rain forest over at least the past 50,000 years. This rain forest expansion is attributed to increased seasonal latitudinal migration of the Intertropical Convergence Zone, which can in turn be explained by Milankovitch astronomic forcing.

  16. Use of riverine through reef habitat systems by dog snapper ( Lutjanus jocu ) in eastern Brazil

    Science.gov (United States)

    Moura, Rodrigo L.; Francini-Filho, Ronaldo B.; Chaves, Eduardo M.; Minte-Vera, Carolina V.; Lindeman, Kenyon C.

    2011-11-01

    The early life history of Western Atlantic snappers from the Southern hemisphere is largely unknown. Habitat use of different life stages (i.e. size categories) of the dog snapper ( Lutjanus jocu) was examined across the largest South Atlantic reef-estuarine complex (Abrolhos Shelf, Brazil, 16-19° S). Visual surveys were conducted in different habitats across the shelf (estuary, inner-shelf reefs and mid-shelf reefs). Lutjanus jocu showed higher densities on inner-shelf habitats, with a clear increase in fish size across the shelf. Individuals 40 cm were recorded only on mid-shelf reefs. Literature data indicate that individuals ranging 70-80 cm are common on deep offshore reefs. This pattern suggests that the dog snapper performs ontogenetic cross-shelf migrations. Protecting portions of the different habitats used by the dog snapper during its post-settlement life cycle is highlighted as an important conservation and management measure.

  17. Recuperation of the Terra Firme Forest Understory Bird Fauna Eight Years after a Wildfire in Eastern Acre, Brazil

    Directory of Open Access Journals (Sweden)

    Tatiana Lemos da Silva

    2015-01-01

    Full Text Available The present study evaluated the characteristics of the understory bird fauna of four fragments of terra firme forest in eastern Acre, Brazil, that were impacted by wildfires in 2005. The study investigated the species richness and the composition of trophic guilds using mist-netting on eight transects (four in burned plots and four in control plots in the same forest fragments. Eight plots (0.12 ha were also established parallel to each transect to record the number of live trees (DBH ≥ 10 cm, palms, and dead trees. Bamboo stems were quantified in 0.024 ha subplots. No significant difference was found between burned and control plots in the species richness or abundance of birds, nor was any significant pattern found in the NMDS ordination of the composition of the communities or guilds. The Principal Components Analysis (PCA found that the burned plots were physiognomically distinct, due principally to the number of bamboo stems and dead trees. Multiple regressions based on the PCA scores and bird species richness and abundance found no significant trends. The findings of the present study indicate that the understory bird assemblage of the areas affected by a single wildfire in 2005 had almost totally recuperated eight years after this event.

  18. Links between riparian landcover, instream environment and fish assemblages in headwater streams of south-eastern Brazil

    Science.gov (United States)

    Cruz, Bruna B.; Miranda, Leandro E.; Cetra, Mauricio

    2013-01-01

    We hypothesised and tested a hierarchical organisation model where riparian landcover would influence bank composition and light availability, which in turn would influence instream environments and control fish assemblages. The study was conducted during the dry season in 11 headwater tributaries of the Sorocaba River in the upper Paraná River Basin, south-eastern Brazil. We focused on seven environmental factors each represented by one or multiple environmental variables and seven fish functional traits each represented by two or more classes. Multivariate direct gradient analyses suggested that riparian zone landcover can be considered a higher level causal factor in a network of relations that control instream characteristics and fish assemblages. Our results provide a framework for a hierarchical conceptual model that identifies singular and collective influences of variables from different scales on each other and ultimately on different aspects related to stream fish functional composition. This conceptual model is focused on the relationships between riparian landcover and instream variables as causal factors on the organisation of stream fish assemblages. Our results can also be viewed as a model for headwater stream management in that landcover can be manipulated to influence factors such as bank composition, substrates and water quality, whereas fish assemblage composition can be used as indicators to monitor the success of such efforts.

  19. Climate and land use changes will degrade the configuration of the landscape for titi monkeys in eastern Brazil.

    Science.gov (United States)

    Gouveia, Sidney F; Souza-Alves, João Pedro; Rattis, Ludmila; Dobrovolski, Ricardo; Jerusalinsky, Leandro; Beltrão-Mendes, Raone; Ferrari, Stephen F

    2016-06-01

    Land use changes have profound effects on populations of Neotropical primates, and ongoing climate change is expected to aggravate this scenario. The titi monkeys from eastern Brazil (Callicebus personatus group) have been particularly affected by this process, with four of the five species now allocated to threatened conservation status categories. Here, we estimate the changes in the distribution of these titi monkeys caused by changes in both climate and land use. We also use demographic-based, functional landscape metrics to assess the magnitude of the change in landscape conditions for the distribution predicted for each species. We built species distribution models (SDMs) based on maximum entropy for current and future conditions (2070), allowing for different global circulation models and contrasting scenarios of glasshouse gas concentrations. We refined the SDMs using a high-resolution map of habitat remnants. We then calculated habitat availability and connectivity based on home-range size and the dispersal limitations of the individual, in the context of a predicted loss of 10% of forest cover in the future. The landscape configuration is predicted to be degraded for all species, regardless of the climatic settings. This include reductions in the total cover of forest remnants, patch size and functional connectivity. As the landscape configuration should deteriorate severely in the future for all species, the prevention of further loss of populations will only be achieved through habitat restoration and reconnection to counteract the negative effects for these and several other co-occurring species.

  20. Harnessing of corneas captured and processed for transplantation in an ocular tissue bank of North-eastern Brazil

    Directory of Open Access Journals (Sweden)

    Izaura Luzia Silvério Freire

    Full Text Available The aim of this study was to describe the harnessing of corneas captured and processed for transplantation in an ocular tissue bank in north-eastern Brazil. This was a transverse and retrospective study, with a sample group of 612 individuals whose corneas were donated and captured between January/2007 and July/2012. This study was approved by the Research Ethics Committee under number 007.0.294.000-10, and research was based on an instrument consisting of social, demographic and clinical data of the donors. Of the 1209 corneas captured, 868 were used and 341 were discarded. Of the 612 donors, the corneas of 597 (97.5% were captured from both eyes, being that 423 (70.9% of these corneas were used. Further studies are required on the reasons for discarding corneas and clarifications as to the conduct of professionals when processing corneas, considering the increase in the quantity of donors and the elevated number of discarded ocular tissue.

  1. Fish gills alterations as potential biomarkers of environmental quality in a eutrophized tropical river in south-eastern Brazil.

    Science.gov (United States)

    Nascimento, A A; Araújo, F G; Gomes, I D; Mendes, R M M; Sales, A

    2012-06-01

    Gill anomalies in three common fish species of different taxonomic order, habitat dwelling and feeding habits (one Characiformes, Oligosarcus hepsetus; one Siluriformes, Hypostomus auroguttatus; and one Perciformes, Geophagus brasiliensis) from a eutrophized tropical river in south-eastern in Brazil were compared. The aim of this study was to search for sentinel species that could be used as potential biomarkers of environmental quality. Most fish had gills with histological changes, namely epithelial lifting, interstitial oedema, leucocyte infiltration, hyperplasia of the epithelial cells, lamellar fusion, vasodilatation and necrosis. On the other hand, lamellar blood congestion and lamellar aneurysm, which are more serious and often irreversible changes, were recorded for the water column carnivorous O. hepsetus and, to a lesser extent, for the bottom-dwelling detritivorous H. auroguttatus. A histopathological alteration index (HAI) based on the occurrence and severity of gills anomalies indicated that O. hepsetus (mean score = 11.4) had significantly higher values (Kruskall-Wallis H(2,41) = 15.95, P = 0.0003) compared with G. brasiliensis (mean score = 7.0). Overall, the omnivorous G. brasiliensis had comparatively lesser occurrence of most gill anomalies compared with other two species, being less suitable as biomarker of environmental quality. In contrast, the water column-dweller O. hepsetus (water column) and the bottom-dweller H. auroguttatus had gills most susceptible to changes, making them more suitable for using as histological biomarkers of the environmental quality in entrophized tropical rivers.

  2. Wildfires in bamboo-dominated Amazonian forest: impacts on above-ground biomass and biodiversity.

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    Jos Barlow

    Full Text Available Fire has become an increasingly important disturbance event in south-western Amazonia. We conducted the first assessment of the ecological impacts of these wildfires in 2008, sampling forest structure and biodiversity along twelve 500 m transects in the Chico Mendes Extractive Reserve, Acre, Brazil. Six transects were placed in unburned forests and six were in forests that burned during a series of forest fires that occurred from August to October 2005. Normalized Burn Ratio (NBR calculations, based on Landsat reflectance data, indicate that all transects were similar prior to the fires. We sampled understorey and canopy vegetation, birds using both mist nets and point counts, coprophagous dung beetles and the leaf-litter ant fauna. Fire had limited influence upon either faunal or floral species richness or community structure responses, and stems <10 cm DBH were the only group to show highly significant (p = 0.001 community turnover in burned forests. Mean aboveground live biomass was statistically indistinguishable in the unburned and burned plots, although there was a significant increase in the total abundance of dead stems in burned plots. Comparisons with previous studies suggest that wildfires had much less effect upon forest structure and biodiversity in these south-western Amazonian forests than in central and eastern Amazonia, where most fire research has been undertaken to date. We discuss potential reasons for the apparent greater resilience of our study plots to wildfire, examining the role of fire intensity, bamboo dominance, background rates of disturbance, landscape and soil conditions.

  3. Brazil.

    Science.gov (United States)

    1985-09-01

    Brazil's population in 1985 was 135 million, with an annual growth rate (1982) of 2.3%. The infant mortality rate (1981) was 92/1000, and life expectancy stood at 62.8 years. 76% of the adult population was literate. Brazil is a federal republic which recognizes 5 political parties. 55% of the population is Portuguese, Italian, German, Japanese, African, or American Indian; 38% is white. Of the work force of 50 million, 35% are engaged in agriculture, 25% work in industry, and 40% are employed in services. Trade union membership totals 6 million. The agricultural sector accounts for 12% of the GDP and 40% of exports. Brazil is largely self-sufficient in terms of food. The GDP was US$218 billion in 1984, with an annual growth rate of 4%. Per capita GDP was US$1645. Brazil's power, transportation, and communications systems have improved greatly in recent years, providing a base for economic development. High inflation rates have been a persistent problem.

  4. Molecular detection of Trypanosoma evansi (Kinetoplastida: Trypanosomatidae in procyonids (Carnivora: Procyonidae in Eastern Amazon, Brazil

    Directory of Open Access Journals (Sweden)

    Paulo Cesar Magalhães-Matos

    2016-04-01

    Full Text Available ABSTRACT: The present study aimed to diagnose the natural infection of captive and free-living procyonids with Trypanosoma evansi in the states of Amapá and Pará, Brazil. From February 2012 to August 2013, whole blood samples and blood smears were obtained from 45 free-living procyonids and from nine procyonids kept in captivity in wild life refuges and zoobotanical parks in the states of Amapá and Pará. Whole blood samples were collected and kept at -20ºC for the detection of T. evansi DNA by PCR using the RoTat 1.2 forward and RoTat 1.2 reverse primers. In addition, the blood smears were processed and examined for the presence of trypomastigote forms of T. evansi. T. evansi DNA was detected in 18.52% (10/54 of the procyonids, namely, in captive crab-eating raccoons and captive and free-living coatis in Pará State. No trypomastigote forms were observed in the blood smears. DNA from T. evansi was detected in P. cancrivorus and N. nasua in Pará State, being this the first such report in P. cancrivorus.

  5. Land-use and environmental changes in the Cerrados of South-Eastern Mato Grosso -- Brazil

    Science.gov (United States)

    Grecchi, Rosana Cristina

    The human-induced changes of the Earth's land surfaces have been unprecedented, with outcomes often indicating degradation and loss of environmental quality. Mato Grosso State in Brazil, location of the study area, underwent extensive land-use and land-cover changes in recent decades with the rates, patterns and consequences poorly documented until now. In this context, the aim of the present research is to propose a multidisciplinary approach for quantifying historical land-use and environmental changes in the southeast part of this State, where the Cerrado biome (Brazilian savannas) has been intensively converted into agricultural lands. The methodology includes three parts: remote sensing change detection, land vulnerability mapping, and identification of key environmental indicators. Land-use/cover information was extracted from a temporal remote sensing dataset using an object-oriented classification approach, and the changes quantified employing a post-classification method. In addition, the study area was assessed for its vulnerabilities, focusing mainly on erosion risks, wetlands, and areas with limited or no suitability for crops. Finally, key environmental indicators were identified from the preceding steps and analyzed within the Organisation for Economic Co-operation and Development (OECD) Pressure-State-Response (PSR) framework. The results provided an improved mapping of the Cerrados natural vegetation conversion into crops and pastures, and indicate that the Cerrado vegetation was intensively converted and also became more fragmented in the time frame studied. Between 1985 and 2005 the area lost approximately 6491 km 2 of Cerrados (42 %). Modeling based on the Universal Soil Loss Equation indicated significant increase in erosion risk from 1985 to 2005 mainly related to the increase in crop areas and the crops' encroachment into more fragile lands. The identification of environmental indicators rendered complex environmental information more

  6. Dynamics of coral reef benthic assemblages of the Abrolhos Bank, eastern Brazil: inferences on natural and anthropogenic drivers.

    Directory of Open Access Journals (Sweden)

    Ronaldo B Francini-Filho

    Full Text Available The Abrolhos Bank (eastern Brazil encompasses the largest and richest coral reefs of the South Atlantic. Coral reef benthic assemblages of the region were monitored from 2003 to 2008. Two habitats (pinnacles' tops and walls were sampled per site with 3-10 sites sampled within different reef areas. Different methodologies were applied in two distinct sampling periods: 2003-2005 and 2006-2008. Spatial coverage and taxonomic resolution were lower in the former than in the latter period. Benthic assemblages differed markedly in the smallest spatial scale, with greater differences recorded between habitats. Management regimes and biomass of fish functional groups (roving and territorial herbivores had minor influences on benthic assemblages. These results suggest that local environmental factors such as light, depth and substrate inclination exert a stronger influence on the structure of benthic assemblages than protection from fishing. Reef walls of unprotected coastal reefs showed highest coral cover values, with a major contribution of Montastraea cavernosa (a sediment resistant species that may benefit from low light levels. An overall negative relationship between fleshy macroalgae and slow-growing reef-building organisms (i.e. scleractinians and crustose calcareous algae was recorded, suggesting competition between these organisms. The opposite trend (i.e. positive relationships was recorded for turf algae and the two reef-building organisms, suggesting beneficial interactions and/or co-occurrence mediated by unexplored factors. Turf algae cover increased across the region between 2006 and 2008, while scleractinian cover showed no change. The need of a continued and standardized monitoring program, aimed at understanding drivers of change in community patterns, as well as to subsidize sound adaptive conservation and management measures, is highlighted.

  7. Dynamics of coral reef benthic assemblages of the Abrolhos Bank, eastern Brazil: inferences on natural and anthropogenic drivers.

    Science.gov (United States)

    Francini-Filho, Ronaldo B; Coni, Ericka O C; Meirelles, Pedro M; Amado-Filho, Gilberto M; Thompson, Fabiano L; Pereira-Filho, Guilherme H; Bastos, Alex C; Abrantes, Douglas P; Ferreira, Camilo M; Gibran, Fernando Z; Güth, Arthur Z; Sumida, Paulo Y G; Oliveira, Nara L; Kaufman, Les; Minte-Vera, Carolina V; Moura, Rodrigo L

    2013-01-01

    The Abrolhos Bank (eastern Brazil) encompasses the largest and richest coral reefs of the South Atlantic. Coral reef benthic assemblages of the region were monitored from 2003 to 2008. Two habitats (pinnacles' tops and walls) were sampled per site with 3-10 sites sampled within different reef areas. Different methodologies were applied in two distinct sampling periods: 2003-2005 and 2006-2008. Spatial coverage and taxonomic resolution were lower in the former than in the latter period. Benthic assemblages differed markedly in the smallest spatial scale, with greater differences recorded between habitats. Management regimes and biomass of fish functional groups (roving and territorial herbivores) had minor influences on benthic assemblages. These results suggest that local environmental factors such as light, depth and substrate inclination exert a stronger influence on the structure of benthic assemblages than protection from fishing. Reef walls of unprotected coastal reefs showed highest coral cover values, with a major contribution of Montastraea cavernosa (a sediment resistant species that may benefit from low light levels). An overall negative relationship between fleshy macroalgae and slow-growing reef-building organisms (i.e. scleractinians and crustose calcareous algae) was recorded, suggesting competition between these organisms. The opposite trend (i.e. positive relationships) was recorded for turf algae and the two reef-building organisms, suggesting beneficial interactions and/or co-occurrence mediated by unexplored factors. Turf algae cover increased across the region between 2006 and 2008, while scleractinian cover showed no change. The need of a continued and standardized monitoring program, aimed at understanding drivers of change in community patterns, as well as to subsidize sound adaptive conservation and management measures, is highlighted.

  8. A large Cervidae Holocene accumulation in Eastern Brazil: an example of extreme taphonomi- cal control in a cave environment

    Directory of Open Access Journals (Sweden)

    Hubbe Alex

    2012-07-01

    Full Text Available A remarkable cervid bone accumulation occurs at a single passage (named Cervid Passage; CP at Lapa Nova, a maze cave in eastern Brazil. CP lies away from cave entrances, is a typical pitfall passage and contains bone remains of at least 121 cervids, besides few bats, peccaries and rodents remains. There is no evidence of water (or sediment flow at the site and in general bones lack post depositional alterations and display anatomical proximity, suggesting that the majority of the remains found inside CP (mainly cervids are due to animals that after entering the cave got trapped in the site. Observations suggest that two entrances could have provided access to cervids (and the few other animals, besides bats, either by falling inside the cave or by entering by their own free will. Once inside the cave, the maze pattern would make route finding difficult, and of all passage intersections, only the one leading to CP would result in a non-return situation, starving the animal to death. Radiocarbon dates suggest that animal entrapment occurred during at least 5 thousand years, during the Holocene. The reasons why mainly cervids were found are unknown but they are probably related to the biology of this group coupled with the fact that caves provide several specific taphonomic processes that may account for a strong bias in bone accumulation. Indeed, the frequent occurrence of Cervidae in both the fossil and sub-fossil record in Brazilian caves may be related to an overall high faunal abundance or may suggest that these animals were especially prone to enter caves, perhaps in search of nutrients (as cave saltpetre or water.

  9. Persistent effects of pre-Columbian plant domestication on Amazonian forest composition.

    Science.gov (United States)

    Levis, C; Costa, F R C; Bongers, F; Peña-Claros, M; Clement, C R; Junqueira, A B; Neves, E G; Tamanaha, E K; Figueiredo, F O G; Salomão, R P; Castilho, C V; Magnusson, W E; Phillips, O L; Guevara, J E; Sabatier, D; Molino, J-F; López, D Cárdenas; Mendoza, A M; Pitman, N C A; Duque, A; Vargas, P Núñez; Zartman, C E; Vasquez, R; Andrade, A; Camargo, J L; Feldpausch, T R; Laurance, S G W; Laurance, W F; Killeen, T J; Nascimento, H E Mendonça; Montero, J C; Mostacedo, B; Amaral, I L; Guimarães Vieira, I C; Brienen, R; Castellanos, H; Terborgh, J; Carim, M de Jesus Veiga; Guimarães, J R da Silva; Coelho, L de Souza; Matos, F D de Almeida; Wittmann, F; Mogollón, H F; Damasco, G; Dávila, N; García-Villacorta, R; Coronado, E N H; Emilio, T; Filho, D de Andrade Lima; Schietti, J; Souza, P; Targhetta, N; Comiskey, J A; Marimon, B S; Marimon, B-H; Neill, D; Alonso, A; Arroyo, L; Carvalho, F A; de Souza, F C; Dallmeier, F; Pansonato, M P; Duivenvoorden, J F; Fine, P V A; Stevenson, P R; Araujo-Murakami, A; Aymard C, G A; Baraloto, C; do Amaral, D D; Engel, J; Henkel, T W; Maas, P; Petronelli, P; Revilla, J D Cardenas; Stropp, J; Daly, D; Gribel, R; Paredes, M Ríos; Silveira, M; Thomas-Caesar, R; Baker, T R; da Silva, N F; Ferreira, L V; Peres, C A; Silman, M R; Cerón, C; Valverde, F C; Di Fiore, A; Jimenez, E M; Mora, M C Peñuela; Toledo, M; Barbosa, E M; Bonates, L C de Matos; Arboleda, N C; Farias, E de Sousa; Fuentes, A; Guillaumet, J-L; Jørgensen, P Møller; Malhi, Y; de Andrade Miranda, I P; Phillips, J F; Prieto, A; Rudas, A; Ruschel, A R; Silva, N; von Hildebrand, P; Vos, V A; Zent, E L; Zent, S; Cintra, B B L; Nascimento, M T; Oliveira, A A; Ramirez-Angulo, H; Ramos, J F; Rivas, G; Schöngart, J; Sierra, R; Tirado, M; van der Heijden, G; Torre, E V; Wang, O; Young, K R; Baider, C; Cano, A; Farfan-Rios, W; Ferreira, C; Hoffman, B; Mendoza, C; Mesones, I; Torres-Lezama, A; Medina, M N U; van Andel, T R; Villarroel, D; Zagt, R; Alexiades, M N; Balslev, H; Garcia-Cabrera, K; Gonzales, T; Hernandez, L; Huamantupa-Chuquimaco, I; Manzatto, A G; Milliken, W; Cuenca, W P; Pansini, S; Pauletto, D; Arevalo, F R; Reis, N F Costa; Sampaio, A F; Giraldo, L E Urrego; Sandoval, E H Valderrama; Gamarra, L Valenzuela; Vela, C I A; Ter Steege, H

    2017-03-03

    The extent to which pre-Columbian societies altered Amazonian landscapes is hotly debated. We performed a basin-wide analysis of pre-Columbian impacts on Amazonian forests by overlaying known archaeological sites in Amazonia with the distributions and abundances of 85 woody species domesticated by pre-Columbian peoples. Domesticated species are five times more likely than nondomesticated species to be hyperdominant. Across the basin, the relative abundance and richness of domesticated species increase in forests on and around archaeological sites. In southwestern and eastern Amazonia, distance to archaeological sites strongly influences the relative abundance and richness of domesticated species. Our analyses indicate that modern tree communities in Amazonia are structured to an important extent by a long history of plant domestication by Amazonian peoples.

  10. Mitochondrial DNA mapping of social-biological interactions in Brazilian Amazonian African-descendant populations

    Directory of Open Access Journals (Sweden)

    Bruno Maia Carvalho

    2008-01-01

    Full Text Available The formation of the Brazilian Amazonian population has historically involved three main ethnic groups, Amerindian, African and European. This has resulted in genetic investigations having been carried out using classical polymorphisms and molecular markers. To better understand the genetic variability and the micro-evolutionary processes acting in human groups in the Brazilian Amazon region we used mitochondrial DNA to investigate 159 maternally unrelated individuals from five Amazonian African-descendant communities. The mitochondrial lineage distribution indicated a contribution of 50.2% from Africans (L0, L1, L2, and L3, 46.6% from Amerindians (haplogroups A, B, C and D and a small European contribution of 1.3%. These results indicated high genetic diversity in the Amerindian and African lineage groups, suggesting that the Brazilian Amazonian African-descendant populations reflect a possible population amalgamation of Amerindian women from different Amazonian indigenous tribes and African women from different geographic regions of Africa who had been brought to Brazil as slaves. The present study partially mapped the historical biological and social interactions that had occurred during the formation and expansion of Amazonian African-descendant communities.

  11. Biomass consumption and CO2, CO and main hydrocarbon gas emissions in an Amazonian forest clearing fire

    Science.gov (United States)

    T. G. Soares Neto; J. A. Carvalho; C. A. G. Veras; E. C. Alvarado; R. Gielow; E. N. Lincoln; T. J. Christian; R. J. Yokelson; J. C. Santos

    2009-01-01

    Biomass consumption and CO2, CO and hydrocarbon gas emissions in an Amazonian forest clearing fire are presented and discussed. The experiment was conducted in the arc of deforestation, near the city of Alta Floresta, state of Mato Grosso, Brazil. The average carbon content of dry biomass was 48% and the estimated average moisture content of fresh biomass was 42% on...

  12. Sightings of Pontoporia blainvillei (Gervais & D' Orbigny, 1844 and Sotalia fluviatilis (Gervais, 1853 (Cetacea in South-eastern Brazil

    Directory of Open Access Journals (Sweden)

    Ana Paula M. Di Beneditto

    2001-09-01

    Full Text Available Pontoporia blainvillei (Gervais & D' Orbigny, 1844 and Sotalia fluviatilis (Gervais, 1853 have typically coastal habits and are sympatric in South-eastern Brazil. The purpose of this work was to record sightings and describe aspects concerning the behaviour of both species in this region, between 1993 and 1998. The sightings were accomplished by cruises and from a fixed point. Information provided by fishermen were also considered. In general, P. blainvillei was observed in all seasons of the year, up to five nautical miles away from the coast, up to 15 m deep and the groups comprised up to five specimens. The most part of the groups of S. fluviatilis, were observed in autumm and winter times and comprised up to 10 specimens. In about half of the sightings, the presence of calves and/or juveniles was noted. The cooperative (group fishing was the foranging behaviour most frequently noted for S. fluviatilis.Pontoporia blainvillei (Gervais & D’Orgigny, 1844 e Sotalia fluviatilis (Gervais, 1853 possuem hábitos tipicamente costeiros e são simpátricas no Sudeste do Brasil. O objetivo deste trabalho foi registrar avistagens e descrever aspectos relacionados ao comportamento de ambas as espécies na região, entre 1993 e 1998. As avistagens foram realizadas através de cruzeiros e ponto fixo. Informações fornecidas por pescadores também foram consideradas. Em geral, P. blainvillei foi observada em todas as estações do ano, a até cinco milhas náuticas de distância da linha da costa e 15 m de profundidade e, os grupos eram formados por até cinco espécimens. A maior parte dos grupos de S. fluviatilis foi observada no período de outono e inverno e, era formada por até 10 espécimens. Em metade das avistagens, a presença de filhotes e/ou juvenis foi verificada. A pesca cooperativa (em grupo foi o comportamento alimentar observado com maior freqüência para S. fluviatilis.

  13. Hyperdominance in Amazonian forest carbon cycling

    NARCIS (Netherlands)

    Fauset, S.; Arets, E.J.M.M.; Steege, ter H.; Pena Claros, M.; Poorter, L.; Levis, C.; Toledo, M.

    2015-01-01

    While Amazonian forests are extraordinarily diverse, the abundance of trees is skewed strongly towards relatively few ‘hyperdominant’ species. In addition to their diversity, Amazonian trees are a key component of the global carbon cycle, assimilating and storing more carbon than any other ecosystem

  14. Geochemistry and geochronology of the rapakivi granites and associated rocks in the midwest portion of the Serra da Providência composite batholith, SW of Amazonian craton, Rondônia, Brazil

    Science.gov (United States)

    Costa, Manoel Augusto Corrêa da; Sousa, Maria Zélia Aguiar de; Dall'Agnol, Roberto; Scandolara, Jaime E.; Ruiz, Amarildo Salina

    2016-08-01

    The Serra da Providência batholith includes the type area of the homonymous suite, the oldest rapakivi magmatic assemblage in the SW of the Amazonian craton (1.60-1.53 Ga). In the midwest portion of this massif, besides wiborgites/pyterlites and granophyric syenogranites, a leucosyenogranite facies and porphyritic rhyolites constitute new rock varieties recently described in that area. Usbnd Pb LA-MC-ICP-MS zircon ages of 1574 ± 9 Ma and 1604 ± 3 Ma, respectively, were obtained for these new varieties and confirm their link with the Serra da Providência magmatism, whereas the subvolcanic rocks are older than the main rock varieties and were formed in a precursor event. These granitic facies are metaluminous to peraluminous, alkali-calcic, A2-type, ferroan granites. Their FeOt/(FeOt + MgO) ratios vary from 0.83 to 0.98 and suggest that these rocks were crystallized from oxidized-to reduced-A-type magmas, where the leucosyenogranites and granophyric sienogranites tend to be formed under more reduced conditions. They show fractionated REE patterns with very pronounced to weak negative Eu anomalies. The presence of granophyric textures and miarolitic cavities in equigranular syenogranitic facies suggests that these rocks were formed at shallow crustal depths, lower than 3 km. Three samples of leucosyenogranite have silica contents higher than 75% and low K/Rb ratios (negative Eu anomalies a feature not observed in the equigranular gabbronorites. Porphyritic gabbronorites geochemical characteristics are similar to calc-alkaline basalts, whereas equigranular gabbronorites are similar to continental basalts. Petrographic, geochemical, and geological data of the felsic facies and the presence of associated mafic rocks corroborate the bimodal and post-collisional character of this magmatism. The occurrence of porphyritic rhyolites associated with shallow level plutonic granites in the Serra da Providência batholith reinforces the similarities between the Rondonian

  15. Variation of biometric parameters and C, N, and P concentrations of Oryza glumaepatula at different depths of an amazonian lake impacted by bauxite tailings (Lake Batata, Pará, Brazil

    Directory of Open Access Journals (Sweden)

    A. ENRICH-PRAST

    Full Text Available Lake Batata is a typical Amazonian clear water lake which has undergone anthropogenic impacts. Thirty percent of its total area has been covered with bauxite tailings. Thus, it is possible to distinguish two areas in this ecosystem: the impacted and the natural. The goal of this research was to study C, N, and P content variation and the values of biomass, length, density, and culm diameter of Oryza glumaepatula at different depths in the natural and impacted areas of Lake Batata. The results obtained in this research suggest that the availability of P and N, in both water and sediment, is lower at the shallow site when compared to the deeper sites. On the other hand, C concentrations decreased as P and N concentrations increased. This may be explained by the structural function of C in aquatic macrophytes. At shallower sites, due to the reduced water column, individuals invest in supporting structures that display high C concentrations. The higher density and biomass of O. glumaepatula at the intermediate site indicate that this area presents the best conditions for germination and establishment of individuals of this species. The chemical composition and biometric parameters of O. glumaepatula have shown that this population has higher spatial variation in the natural area. In the impacted area, the absence of significant variations in N and P concentrations in O. glumaepatula among the three sampled sites promotes higher homogeneity in the stands. The high C:P and N:P ratios indicate that, in the impacted area, P is more limiting to the development of O. glumaepatula than it is in the natural area. The reduced values of biomass and density of O. glumaepatula in the impacted area suggest that the bauxite tailings limit the development of this population.

  16. Characterization of the volcanic and hypabissal rocks of the Paleoproterozoic Iricoumé Group in the Pitinga region and Balbina Lake area, Amazonian Craton, Brazil: Petrographic distinguishing features and emplacement conditions

    Science.gov (United States)

    Simões, Matheus Silva; Almeida, Marcelo Esteves; de Souza, Antonio Gilmar Honorato; da Silva, Desaix Paulo Balieiro; Rocha, Paloma Gabriela

    2014-10-01

    The Iricoumé Group (1.897 to 1.875 Ma) is a widespread volcanic sequence in the Amazonian Craton, South American Platform. In the Pitinga region, it consists of acidic to intermediate ignimbrites with cogenetic surge and ash-fall deposits associated to hypabissal and effusive acidic rocks. In the Balbina Lake area it consists of acidic to intermediate effusive rocks, crystal-rich ignimbrites and pumice-rich ignimbrites. Detailed petrographic studies of phenocrysts and crystal fragments provided characterization and distinctive features of pyroclastic, effusive and hypabissal rocks. The phenocrysts of hypabissal rocks were affected by high temperature resorption and flow-related physical fragmentation, the effusive rocks can have a considerable content of crystal fragments due to intense dissolution and fragmentation of the phenocrysts and the pyroclastic rocks crystal fragments are generated mainly by decompression mechanic fragmentation. Dissolution and resorption of quartz and feldspar crystals may have acted at pressure conditions between 500 MPa and 100 MPa, in response to rapid decompression in the magma ascent. The viscosity values of 7,5-10 log η (Pa s) for anhydrous conditions decrease exponentially with estimated water addition. The amount of phenocrysts and their intratelluric character in the volcanic units of Iricoumé Group can be related to a magma chamber with high content of crystals. We suggest that even with the addition of water in the magma, the viscosities had a drastic increase with progressive crystal growth due to the viscosity dependence on the solid fraction and the deposits were generated by the extrusion of viscous lava and pyroclastic flows.

  17. Variation of biometric parameters and C, N, and P concentrations of Oryza glumaepatula at different depths of an Amazonian lake impacted by bauxite tailings (Lake Batata, Pará, Brazil).

    Science.gov (United States)

    Enrich-Prast, A; Esteves, F A; Breves, A R

    2002-02-01

    Lake Batata is a typical Amazonian clear water lake which has undergone anthropogenic impacts. Thirty percent of its total area has been covered with bauxite tailings. Thus, it is possible to distinguish two areas in this ecosystem: the impacted and the natural. The goal of this research was to study C, N, and P content variation and the values of biomass, length, density, and culm diameter of Oryza glumaepatula at different depths in the natural and impacted areas of Lake Batata. The results obtained in this research suggest that the availability of P and N, in both water and sediment, is lower at the shallow site when compared to the deeper sites. On the other hand, C concentrations decreased as P and N concentrations increased. This may be explained by the structural function of C in aquatic macrophytes. At shallower sites, due to the reduced water column, individuals invest in supporting structures that display high C concentrations. The higher density and biomass of O. glumaepatula at the intermediate site indicate that this area presents the best conditions for germination and establishment of individuals of this species. The chemical composition and biometric parameters of O. glumaepatula have shown that this population has higher spatial variation in the natural area. In the impacted area, the absence of significant variations in N and P concentrations in O. glumaepatula among the three sampled sites promotes higher homogeneity in the stands. The high C:P and N:P ratios indicate that, in the impacted area, P is more limiting to the development of O. glumaepatula than it is in the natural area. The reduced values of biomass and density of O. glumaepatula in the impacted area suggest that the bauxite tailings limit the development of this population.

  18. The orchid-bee fauna (Hymenoptera: Apidae of ‘Reserva Biológica de Una’, a hotspot in the Atlantic Forest of southern Bahia, eastern Brazil

    Directory of Open Access Journals (Sweden)

    A Nemésio

    Full Text Available The orchid-bee fauna of ‘Reserva Biológica de Una’ (REBIO Una, one of the largest Atlantic Forest remnants in southern Bahia, eastern Brazil, was surveyed for the first time. Baits with sixteen different scents were used to attract males of orchid bees. Eight hundred and fifty-nine males belonging to 26 species were actively collected with insect nets during 60 hours in January and February, 2009, and January, 2010. Euglossa avicula Dressler, 1982 and Euglossa milenae Bembé, 2007 have been recorded for the first time in the state of Bahia. It was found that REBIO Una has one of the most diverse and rich orchid-bee faunas of the entire Atlantic Forest domain and holds some rare species, such as Euglossa cyanochloraMoure, 1996.

  19. Prevalence of enteroaggregative Escherichia coli and its virulence-related genes in a case-control study among children from north-eastern Brazil.

    Science.gov (United States)

    Lima, Ila Fernanda Nunes; Boisen, Nadia; Quetz, Josiane da Silva; Havt, Alexandre; de Carvalho, Eunice Bobo; Soares, Alberto Melo; Lima, Noélia Leal; Mota, Rosa Maria Salani; Nataro, James P; Guerrant, Richard Littleton; Lima, Aldo Ângelo Moreira

    2013-05-01

    Enteroaggregative Escherichia coli (EAEC) is an important agent that causes endemic and epidemic diarrhoeal diseases worldwide. Several EAEC virulence-related genes (VRGs) have been described but their role in the clinical outcome of infection is not completely defined. This study investigated the prevalence of EAEC and potential associations of its VRGs with risk of or protection from diarrhoeal diseases in children from urban communities in north-eastern Brazil. The case-control study included 166 children, who had their stools evaluated for the EAEC diagnostic genes (aaiC and aatA) using PCR. Positive samples were further analysed by multiplex PCR and identified 18 VRGs. EAEC was found in the same proportion in both groups (41%). The plasmid-borne gene encoding a hexosyltransferase homologue (capU) was the most frequently detected (89.6%), followed by dispersin protein (aap, 58.2%) and EAEC HilA homologue (eilA, 57.8%). The AAF/III fimbrial subunit (agg3A) gene was observed at lower frequency (1.5%). Plasmid-encoded toxin (pet) or AAF/II fimbrial subunit (aafA) was associated significantly with disease. AAF/IV fimbrial subunit (agg4A) or hypothetical plasmid-encoded haemolysin (orf61) was detected significantly more in controls than in children with diarrhoea. In addition, one set of genes in combination, aaiC and agg3/4C but lacking agg4A and orf61, was associated with diarrhoea cases; and another one, orf61 in the absence of pet and aafA, was correlated with control children. These data confirm a high prevalence, endemicity and heterogeneity of EAEC strains in the developing urban areas of north-eastern Brazil. Statistical correlation between cases and controls was seen with either isolated or combined sets of genes, suggesting that the pathophysiology of EAEC infection involves a complex and dynamic modulation of several VRGs.

  20. Prevalence of enteroaggregative Escherichia coli and its virulence-related genes in a case–control study among children from north-eastern Brazil

    Science.gov (United States)

    Boisen, Nadia; Quetz, Josiane da Silva; Havt, Alexandre; de Carvalho, Eunice Bobo; Soares, Alberto Melo; Mota, Rosa Maria Salani; Nataro, James P.; Guerrant, Richard Littleton

    2013-01-01

    Enteroaggregative Escherichia coli (EAEC) is an important agent that causes endemic and epidemic diarrhoeal diseases worldwide. Several EAEC virulence-related genes (VRGs) have been described but their role in the clinical outcome of infection is not completely defined. This study investigated the prevalence of EAEC and potential associations of its VRGs with risk of or protection from diarrhoeal diseases in children from urban communities in north-eastern Brazil. The case–control study included 166 children, who had their stools evaluated for the EAEC diagnostic genes (aaiC and aatA) using PCR. Positive samples were further analysed by multiplex PCR and identified 18 VRGs. EAEC was found in the same proportion in both groups (41 %). The plasmid-borne gene encoding a hexosyltransferase homologue (capU) was the most frequently detected (89.6 %), followed by dispersin protein (aap, 58.2 %) and EAEC HilA homologue (eilA, 57.8 %). The AAF/III fimbrial subunit (agg3A) gene was observed at lower frequency (1.5 %). Plasmid-encoded toxin (pet) or AAF/II fimbrial subunit (aafA) was associated significantly with disease. AAF/IV fimbrial subunit (agg4A) or hypothetical plasmid-encoded haemolysin (orf61) was detected significantly more in controls than in children with diarrhoea. In addition, one set of genes in combination, aaiC and agg3/4C but lacking agg4A and orf61, was associated with diarrhoea cases; and another one, orf61 in the absence of pet and aafA, was correlated with control children. These data confirm a high prevalence, endemicity and heterogeneity of EAEC strains in the developing urban areas of north-eastern Brazil. Statistical correlation between cases and controls was seen with either isolated or combined sets of genes, suggesting that the pathophysiology of EAEC infection involves a complex and dynamic modulation of several VRGs. PMID:23429698

  1. Late Amazonian Glaciations in Utopia Planitia, Mars

    Science.gov (United States)

    Osinski, G. R.; Capitan, R. D.; Kerrigan, M.; Barry, N.; Blain, S.

    2012-03-01

    We present evidence from western Utopia Planitia, including lineated valley fill and lobate debris aprons, for widespread glaciations over a large expanse of the northern plains and dichotomy boundary during Late Amazonian times.

  2. Organic carbon stocks in the soils of Brazil

    NARCIS (Netherlands)

    Batjes, N.H.

    2005-01-01

    Soil organic carbon stocks to 1 m for Brazil, calculated using an updated Soil and Terrain (SOTER) database and simulation of phenoforms, are 65.9-67.5 Pg C, of which 65% is in the Amazonian region of Brazil. Other researchers have obtained similar gross results, despite very different spatial patte

  3. Heavy Rainfall Episodes in the Eastern Northeast Brazil Linked to Large-Scale Ocean-Atmosphere Conditions in the Tropical Atlantic

    Directory of Open Access Journals (Sweden)

    Yves K. Kouadio

    2012-01-01

    Full Text Available Relationships between simultaneous occurrences of distinctive atmospheric easterly wave (EW signatures that cross the south-equatorial Atlantic, intense mesoscale convective systems (lifespan > 2 hour that propagate westward over the western south-equatorial Atlantic, and subsequent strong rainfall episodes (anomaly > 10 mm·day−1 that occur in eastern Northeast Brazil (ENEB are investigated. Using a simple diagnostic analysis, twelve cases with EW lifespan ranging between 3 and 8 days and a mean velocity of 8 m·s−1 were selected and documented during each rainy season of 2004, 2005, and 2006. These cases, which represent 50% of the total number of strong rainfall episodes and 60% of the rainfall amount over the ENEB, were concomitant with an acceleration of the trade winds over the south-equatorial Atlantic, an excess of moisture transported westward from Africa to America, and a strengthening of the convective activity in the oceanic region close to Brazil. Most of these episodes occurred during positive sea surface temperature anomaly patterns over the entire south-equatorial Atlantic and low-frequency warm conditions within the oceanic mixing layer. A real-time monitoring and the simulation of this ocean-atmosphere relationship could help in forecasting such dramatic rainfall events.

  4. Impact of pre-Columbian "geoglyph" builders on Amazonian forests.

    Science.gov (United States)

    Watling, Jennifer; Iriarte, José; Mayle, Francis E; Schaan, Denise; Pessenda, Luiz C R; Loader, Neil J; Street-Perrott, F Alayne; Dickau, Ruth E; Damasceno, Antonia; Ranzi, Alceu

    2017-02-21

    Over 450 pre-Columbian (pre-AD 1492) geometric ditched enclosures ("geoglyphs") occupy ∼13,000 km(2) of Acre state, Brazil, representing a key discovery of Amazonian archaeology. These huge earthworks were concealed for centuries under terra firme (upland interfluvial) rainforest, directly challenging the "pristine" status of this ecosystem and its perceived vulnerability to human impacts. We reconstruct the environmental context of geoglyph construction and the nature, extent, and legacy of associated human impacts. We show that bamboo forest dominated the region for ≥6,000 y and that only small, temporary clearings were made to build the geoglyphs; however, construction occurred within anthropogenic forest that had been actively managed for millennia. In the absence of widespread deforestation, exploitation of forest products shaped a largely forested landscape that survived intact until the late 20th century.

  5. Virtual population analysis of two snapper species, Lutjanus analis and Lutjanus chrysurus, caught off Pernambuco State, north-eastern Brazil

    Directory of Open Access Journals (Sweden)

    Sérgio Macedo Gomes de Mattos

    2009-09-01

    Full Text Available We applied steady-state Virtual Population Analysis - VPA to two stocks of snappers (Lutjanus analis and L. chrysurus exploited by artisanal hand-line fleets along the Pernambuco State coast (North-eastern Brazil. We show that even short-data series (1 year of sampling can produce a useful diagnosis of fisheries resources. Both stocks are slightly overexploited by the hand-line fishery and a higher yield-per-recruit would be obtained by a reduction of effort of 16% for L. analis and 43% for L. chrysurus. Given the impracticability of managing the two stocks separately, we propose a 25% decrease of fishing effort for the hand-line fleet. By incorporating the results of VPA into a simulation framework, we can develop a comparison of the likely result of different policy options (effort regulation based on 3 simple indicators (Spawning stock biomass-per-recruit, biomass-perrecruit and yield-per-recruit. We compare the results of effort reduction with those of effort increase (25% through simulation analysis. Allowing for the difficulty of testing assumptions introduced in our model (steady-state, Beverton and Holt recruitment model and using standard fisheries analysis techniques, we show that useful fisheries advice can be produced even in a context of limited data. Providing advice to developing countries coastal fisheries is an urgent issue, given the high dependence of local communities on coastal living resources and the increasing fishing effort applied by a growing population.Foi aplicado a Análise Virtual de População - VPA em estado estacionário a dois estoques de lutjanídeos (Lutjanus analis e L. chrysurus explorados pela frota artesanal de linha de mão ao longo da costa do Estado de Pernambuco (Nordeste do Brasil. Demonstrou-se que mesmo para uma série de dados não-históricos (1 ano de amostragem pode-se produzir um diagnóstico útil dos recursos pesqueiros e que ambos os estoques estão próximo ao estado de sobrexplotação e

  6. Effect of oil palm on the Plecoptera and Trichoptera (Insecta) assemblages in streams of eastern Amazon.

    Science.gov (United States)

    de Paiva, Carina Kaory Sasahara; de Faria, Ana Paula Justino; Calvão, Lenize Batista; Juen, Leandro

    2017-08-01

    The production of oil palm is expected to increase in the Amazon region. However, expansion of oil palm plantation leads to significant changes in the physical structure of aquatic ecosystems, mainly through the reduction of riparian vegetation that is essential for aquatic biodiversity. Here, we evaluated the effects of oil palm on the physical habitat structure of Amazonian stream environments and assemblages of Plecoptera and Trichoptera (PT), ​both found in these streams. We compared streams sampled in oil palm plantations (n = 13) with natural forest areas ("reference" streams, n = 8), located in the eastern Amazon, Brazil. Our results showed that oil palm streams were more likely to be in close proximity to roads, had higher pH values, and higher amounts of fine substrate deposited in the channel than reference streams. Further, these environmental changes had important effects on the aquatic invertebrate assemblages, reducing the abundance and richness of PT. Nevertheless, the genera composition of the assemblages did not differ between reference and oil palm (PERMANOVA, pseudo-F (1,19) = 1.891; p = 0.111). We conclude that oil palm production has clear negative impacts on aquatic environments and PT assemblages in Amazonian streams. We recommend that oil palm producers invest more in planning of road networks to avoid the construction of roads near to the riparian vegetation. This planning can minimize impacts of oil palm production on aquatic systems in the Amazon.

  7. Paleoproterozoic (~1.88Ga felsic volcanism of the Iricoumé Group in the Pitinga Mining District area, Amazonian Craton, Brazil: insights in ancient volcanic processes from field and petrologic data

    Directory of Open Access Journals (Sweden)

    Ronaldo Pierosan

    2011-09-01

    Full Text Available The Iricoumé Group correspond to the most expressive Paleoproterozoic volcanism in the Guyana Shield, Amazonian craton. The volcanics are coeval with Mapuera granitoids, and belong to the Uatumã magmatism. They have U-Pb ages around 1880 Ma, and geochemical signatures of α-type magmas. Iricoumé volcanics consist of porphyritic trachyte to rhyolite, associated to crystal-rich ignimbrites and co-ignimbritic fall tuffs and surges. The amount and morphology of phenocrysts can be useful to distinguish lava (flow and dome from hypabyssal units. The morphology of ignimbrite crystals allows the distinction between effusive units and ignimbrite, when pyroclasts are obliterated. Co-ignimbritic tuffs are massive, and some show stratifications that suggest deposition by current traction flow. Zircon and apatite saturation temperatures vary from 799°C to 980°C, are in agreement with most temperatures of α-type melts and can be interpreted as minimum liquidus temperature. The viscosities estimation for rhyolitic and trachytic compositions yield values close to experimentally determined melts, and show a typical exponential decay with water addition. The emplacement of Iricoumé volcanics and part of Mapuera granitoids was controlled by ring-faults in an intracratonic environment. A genesis related to the caldera complex setting can be assumed for the Iricoumé-Mapuera volcano-plutonic association in the Pitinga Mining District.O Grupo Iricoumé corresponde ao mais expressivo vulcanismo Paleoproterozóico do Escudo das Guianas, craton Amazônico. As rochas vulcânicas são coexistentes com os granitóides Mapuera, e pertencem ao magmatismo Uatumã. Possuem idades U-Pb em torno 1888 Ma, e assinaturas geoquímicas de magmas tipo-A. As vulcânicas do Iricoumé consistem de traquitos a riolitos porfiríticos, associados a ignimbritos ricos em cristal e tufos co-ignimbríticos de queda e surge. A quantidade e a morfologia dos fenocristais podem ser

  8. FOREST LITTER DECOMPOSITION AS AFFECTED BY EUCALYPTUS STAND AGE AND TOPOGRAPHY IN SOUTH-EASTERN BRAZIL1

    OpenAIRE

    Alba Lucia Araujo Skorupa; Nairam Félix de Barros; Júlio César Lima Neves

    2015-01-01

    Forest litter decomposition is a major process in returning nutrients to soils and thus promoting wood productivity in the humid tropic. This study aimed to assess decomposition of eucalypt litter in the Rio Doce region, Brazil. Leaf litter was sampled under clonal eucalypt stands aged 2, 4 and 6 years on hillslopes and footslopes. Soil and soil+litter samples were incubated at two levels of soil moisture, temperature and fertilization. C-CO2 emissions from soil measured during 106 days were ...

  9. Resposta de cultivares de pimenta-do-reino aos nutrientes NPK em um Latossolo Amarelo da Amazônia Oriental Response of NPK fertilization by black pepper cultivars in an Eastern Amazonian Yellow Latosol

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    Carlos Alberto Costa Veloso

    2000-06-01

    Full Text Available O presente trabalho foi desenvolvido, com o objetivo de estabelecer curvas de resposta da pimenteira-do-reino a nitrogênio, fósforo e potássio, num Latossolo Amarelo distrófico (Oxisol, no município de Senador José Porfírio, km 35 da rodovia Transamazônica. As doses de nitrogênio, aplicadas manualmente a cada ano foram: (0; 40; 80; 120 e 160 kg ha-1 de N na forma de uréia, cinco doses de fósforo (0; 30; 60; 90 e 120 kg ha-1 P2O5 na forma de superfosfato triplo e cinco doses de potássio (0; 30; 60; 90 e 120 kg ha-1 K2O na forma de KCl. Utilizou-se o delineamento em blocos ao acaso, com três repetições, sendo os tratamentos dispostos em esquema fatorial incompleto.O espaçamento foi de 3,0 m entre linhas e 2,5 m entre plantas, com seis plantas úteis por parcela. Os resultados evidenciaram resposta positiva de nitrogênio com relação a produção de grãos de pimenta do reino com a aplicação de 72 e 78 kg ha-1 de N, para as cultivares Cingapura e Bragantina, respectivamente. Somente a cultivar Guajarina, respondeu à aplicação de fósforo. Doses crescentes de K2O, reduziu os teores de potássio presentes no tecido foliar das pimenteiras. A adição de potássio favoreceu o aumento da produção de grãos com a aplicação de 42, 13 e 22 kg ha-1 de K2O, para as cultivares Cingapura, Bragantina e Guajarina, respectivamente.The present work was developed with the objective of establishing response curves of black pepper to nitrogen, phosphorus and potassium in an Oxisol (Yellow Latosol, dystrophic in Senador José Porfírio County, km 35 of the Transamazonian road, in Brazil. The levels of nitrogen, applied manually every year were (0; 40; 80; 120 and 160 kg ha-1 N in the urea form, five phosphorus levels (0; 30; 60; 90 and 120 kg ha-1 P2O5 in the form of triple superphosphate and five potassium levels (0; 30; 60; 90 and 120 kg ha-1 K2O in the form of potassium chloride. The experimental design consisted of blocks with three

  10. Diet of Eared Doves (Zenaida auriculata, Aves, Columbidae in a sugar-cane colony in South-eastern Brazil

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    R. RANVAUD

    Full Text Available Farmers in the Paranapanema Valley (São Paulo, Brazil have reported problems with flocks of Eared Doves (Zenaida auriculata eating sprouting soybeans. In this region these birds breed colonially in sugar-cane, and eat four crop seeds, using 70% of the dry weight, in the following order of importance: maize, wheat, rice, and soybeans. Three weeds (Euphorbia heterophylla, Brachiaria plantaginea, and Commelina benghalensis were important. This information suggests that the doves adapted particularly well to the landscape created by the agricultural practices in the region, exploiting many available foods.

  11. Increasing efficiency in ethanol production: Water footprint and economic productivity of sugarcane ethanol under nine different water regimes in north-eastern Brazil

    Directory of Open Access Journals (Sweden)

    Daniel Chico

    2015-06-01

    Full Text Available Ethanol production in Brazil has grown by 219% between 2001 and 2012, increasing the use of land and water resources. In the semi-arid north-eastern Brazil, irrigation is the main way for improving sugarcane production. This study aimed at quantifying water consumed in ethanol production from sugarcane in this region using the water footprint (WF indicator and complementing it with an evaluation of the water apparent productivity (WAP. This way we were able to provide a measure of the crop´s physical and economic water productivity using, respectively, the WF and WAP concepts. We studied sugarcane cultivation under nine different water regimes, including rainfed and full irrigation. Data from a mill of the state of Alagoas for three production seasons were used. Irrigation influenced sugarcane yield increasing total profit per hectare and economic water productivity. Full irrigation showed the lowest WF, 1229 litres of water per litre of ethanol (L/L, whereas rainfed production showed the highest WF, 1646 L/L. However, the lower WF in full irrigation as compared to the rest of the water regimes implied the use of higher volumes of blue water per cultivated hectare. Lower water regimes yielded the lowest economic productivity, 0.72 US$/m3 for rainfed production as compared to 1.11 US$/m3 for full irrigation. Since economic revenues are increased with higher water regimes, there are incentives for the development of these higher water regimes. This will lead to higher general crop water and economic productivity at field level, as green water is replaced by blue water consumption.

  12. Ecology of sand flies in a low-density residential rural area, with mixed forest/agricultural exploitation, in north-eastern Brazil.

    Science.gov (United States)

    Miranda, Débora Elienai de Oliveira; Sales, Kamila Gaudêncio da Silva; Faustino, Maria Aparecida da Gloria; Alves, Leucio Câmara; Brandão-Filho, Sinval Pinto; Dantas-Torres, Filipe; de Carvalho, Gílcia Aparecida

    2015-06-01

    Cutaneous leishmaniasis caused by Leishmania braziliensis is endemic in Brazil, where Lutzomyia whitmani is the most important vector involved in the transmission to humans, particularly in the peridomestic environment. Herein, we assessed the ecology of sand flies, including Lu. whitmani, in a low-density residential rural area with mixed forest/agricultural exploitation in north-eastern Brazil, where cutaneous leishmaniasis is endemic. Particularly, we hypothesized that sand fly abundance was correlated with climatic variables. Sand fly collections were carried out monthly from August 2013 to August 2014, using seven CDC light traps, for three consecutive nights, in three kinds of environments: indoor, peridomicile and forest. Collected sand flies were identified based on morphology and females of Lu. whitmani (n=169), Lu. amazonensis (n=134) and Lu. complexa (n=21) were selected and tested by PCR for Leishmania (Viannia) spp. In total, 5167 sand flies belonging to 19 species were identified, being that Lu. choti (43.2%) was the most frequent species, followed by Lu. amazonensis (16.6%), Lu. whitmani (15.8%), Lu. sordellii (10.7%) and Lu. quinquefer (5.8%), which together represented over 90% of the collected sand flies. All females tested by PCR were negative. The number of sand flies collected daily was positively correlated with temperature and negatively correlated with rainfall and relative humidity. Furthermore, there was a positive correlation between daily number of sand flies and daily average saturation deficit. This study points out that the number of sand flies captured daily is correlated to climatic variables, including saturation deficit, which may represent a useful parameter for monitoring sand fly populations in leishmaniasis-endemic areas.

  13. Increasing efficiency in ethanol production: Water footprint and economic productivity of sugarcane ethanol under nine different water regimes in north-eastern Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Chico, D.; Santiago, A. D.; Garrido, A.

    2015-07-01

    Ethanol production in Brazil has grown by 219% between 2001 and 2012, increasing the use of land and water resources. In the semi-arid north-eastern Brazil, irrigation is the main way for improving sugarcane production. This study aimed at quantifying water consumed in ethanol production from sugarcane in this region using the water footprint (WF) indicator and complementing it with an evaluation of the water apparent productivity (WAP). This way we were able to provide a measure of the crop´s physical and economic water productivity using, respectively, the WF and WAP concepts. We studied sugarcane cultivation under nine different water regimes, including rainfed and full irrigation. Data from a mill of the state of Alagoas for three production seasons were used. Irrigation influenced sugarcane yield increasing total profit per hectare and economic water productivity. Full irrigation showed the lowest WF, 1229 litres of water per litre of ethanol (L/L), whereas rainfed production showed the highest WF, 1646 L/L. However, the lower WF in full irrigation as compared to the rest of the water regimes implied the use of higher volumes of blue water per cultivated hectare. Lower water regimes yielded the lowest economic productivity, 0.72 US$/m3 for rainfed production as compared to 1.11 US$/m3 for full irrigation. Since economic revenues are increased with higher water regimes, there are incentives for the development of these higher water regimes. This will lead to higher general crop water and economic productivity at field level, as green water is replaced by blue water consumption. (Author)

  14. Composition and conservation of Orchidaceae on an inselberg in the Brazilian Atlantic Forest and floristic relationships with areas of Eastern Brazil.

    Science.gov (United States)

    Pessanha, Alexandre Soares; Menini Neto, Luiz; Forzza, Rafaela Campostrini; Nascimento, Marcelo Trindade

    2014-06-01

    The Brazilian Atlantic Forest presents high levels of richness and endemism of several taxonomic groups. Within this forest, the Orchidaceae may be highlighted as the richest family of Angiosperms found there, and is highly threatened due to collection and habitat destruction. The inselbergs of the Brazilian Atlantic Forest are mostly unknown regarding their floristic composition, but the available information points to occurrence of endemic species, with adaptations to survive to this dry environment. The objectives of this study were to conduct a floristic survey of the Orchidaceae species on the Maciço do Itaoca, an inselberg located in the Northern region of the State of Rio de Janeiro, make a comparative analysis with other sites in Eastern Brazil, and discuss the geographic distribution, floristic relationships and conservation status of the orchid species present on the inselbergs. The floristic composition of the study area was compared with 24 other locations in Eastern Brazil (of which 13 are inselbergs) and the influence of the types of surrounding vegetation on the composition of the Orchidaceae flora on the inselbergs. On Maciço do Itaoca we recorded 18 species from 17 genera: Brasiliorchis picta, Brassavola tuberculata, Campylocentrum robustum; C sellowii, Catasetum luridum, Cattleya guttata, Cyclopogon congestus, Cyrtopodium glutiniferum, Leptotes bicolor, Lophiaris pumila, Miltonia moreliana, Oeceoclades maculata, Phymatochilum brasiliense, Prescottia plantaginifolia, Pseudolaelia vellozicola, Sarcoglottis fasciculata, Sophronitis cernua. and Vanilla chamissonis. The highest floristic similarity was with the Pedra da Botelha (0.43), an inselberg located in the North of Espírito Santo. This result is probably due to the similarity in altitude and distance from the coast in both areas despite the geographical distance between them. Apparently, little influence is exerted by the types of surrounding vegetation on the composition of the flora of

  15. Biological spectrum and dispersal syndromes in an area of the semi-arid region of north-eastern Brazil

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    Elimar Alves de Lima

    2015-03-01

    Full Text Available The biological spectrum and diaspores dispersal syndromes of the species recorded in a stretch of vegetation in a semi-arid region within the Cariri Environment Protection Area, Boa Vista, Paraíba State (northeast Brazil, are described. Collections were made from fertile specimens, preferentially bearing fruit, over a 15-month period. Life forms and syndromes were determined by field observations using specialized literature. One hundred and sixty-six species, distributed into 123 genera and 41 families, were reported. Abiotic syndromes (autochory and anemochory represented 69.7% of all syndromes identified, whilst 30.3% of the species were classified as zoochory. In the life form spectrum therophytes represented 27.7% of species, followed by small- and medium-sized phanerophytes (23.5% and chamaephytes (22.3%. The occurrence of hemicryptophytes (9%, cryptophytes (0.6% and species that could not be classified according to their life forms was also recorded (16.9%. Results showed that the biological spectrum and the dispersal syndromes are highly relevant to understand the structure and function of this phytocenose, with subsidies for the development of other studies in the semi-arid areas of northeastern Brazil.

  16. The orchid-bee faunas (Hymenoptera: Apidae of two Atlantic Forest remnants in southern Bahia, eastern Brazil

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    A Nemésio

    Full Text Available The orchid-bee faunas of the ‘Parque Nacional do Pau Brasil’ (8,500 ha and ‘RPPN Estação Veracel’ (6,000 ha, two Atlantic Forest remnants in the southern state of Bahia, northeastern Brazil, were surveyed. Seventeen chemical compounds were used as scent baits to attract orchid-bee males. Seven hundred and twelve males belonging to 20 species were actively collected with insect nets during 80 hours in February and April, 2009. Euglossa marianae Nemésio, 2011, the most sensitive orchid-bee species of the Atlantic Forest, was recorded at both preserves, though in low abundance. ‘RPPN Estação Veracel’ is the smallest forest patch where Euglossa marianae has ever been recorded.

  17. Bathymetric survey of water reservoirs in north-eastern Brazil based on TanDEM-X satellite data.

    Science.gov (United States)

    Zhang, Shuping; Foerster, Saskia; Medeiros, Pedro; de Araújo, José Carlos; Motagh, Mahdi; Waske, Bjoern

    2016-11-15

    Water scarcity in the dry season is a vital problem in dryland regions such as northeastern Brazil. Water supplies in these areas often come from numerous reservoirs of various sizes. However, inventory data for these reservoirs is often limited due to the expense and time required for their acquisition via field surveys, particularly in remote areas. Remote sensing techniques provide a valuable alternative to conventional reservoir bathymetric surveys for water resource management. In this study single pass TanDEM-X data acquired in bistatic mode were used to generate digital elevation models (DEMs) in the Madalena catchment, northeastern Brazil. Validation with differential global positioning system (DGPS) data from field measurements indicated an absolute elevation accuracy of approximately 1m for the TanDEM-X derived DEMs (TDX DEMs). The DEMs derived from TanDEM-X data acquired at low water levels show significant advantages over bathymetric maps derived from field survey, particularly with regard to coverage, evenly distributed measurements and replication of reservoir shape. Furthermore, by mapping the dry reservoir bottoms with TanDEM-X data, TDX DEMs are free of emergent and submerged macrophytes, independent of water depth (e.g. >10m), water quality and even weather conditions. Thus, the method is superior to other existing bathymetric mapping approaches, particularly for inland water bodies. The proposed approach relies on (nearly) dry reservoir conditions at times of image acquisition and is thus restricted to areas that show considerable water levels variations. However, comparisons between TDX DEM and the bathymetric map derived from field surveys show that the amount of water retained during the dry phase has only marginal impact on the total water volume derivation from TDX DEM. Overall, DEMs generated from bistatic TanDEM-X data acquired in low water periods constitute a useful and efficient data source for deriving reservoir bathymetry and show

  18. The orchid-bee faunas (Hymenoptera: Apidae) of 'Parque Nacional do Monte Pascoal', 'Parque Nacional do Descobrimento' and three other Atlantic Forest remnants in southern Bahia, eastern Brazil.

    Science.gov (United States)

    Nemésio, A

    2013-05-01

    The orchid-bee faunas of 'Parque Nacional do Monte Pascoal', 'Parque Nacional do Descobrimento' and three other Atlantic Forest remnants ranging from 1 to 300 ha in southern Bahia, eastern Brazil, were surveyed. Baits with seventeen different scents were used to attract orchid-bee males. Four thousand seven hundred and sixty-four males belonging to 36 species were actively collected with insect nets during 300 hours from November, 2008 to November, 2009. Richness and diversity of orchid bees found in this study are the highest ever recorded in the Atlantic Forest domain. Eufriesea dentilabris (Mocsáry, 1897) and Eufriesea violacea (Blanchard, 1840) were collected at the 'Parque Nacional do Monte Pascoal', the first record of these species for the state of Bahia and the northernmost record for both species. Females Exaerete dentata (Linnaeus, 1758) were also collected at 'Parque Nacional do Monte Pascoal' and old records of Eufriesea aeneiventris (Mocsáry, 1896) in this area makes this site the richest and most diverse concerning its orchid-bee fauna in the entire Atlantic Forest and similar to areas in the Amazon Basin.

  19. Characterization of non-calcareous 'thin' red clay from south-eastern Brazil: applicability in wall tile manufacture

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, S.J.G.; Holanda, J.N.F., E-mail: sidnei_rjsousa@yahoo.com.br, E-mail: holanda@uenf.br [Grupo de Materiais Ceramicos - LAMAV-CCT, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, RJ (Brazil)

    2012-04-15

    In this work the use of 'thin' red clay from south-eastern Brazil (Campos dos Goytacazes, RJ) as raw material for the manufacture of wall tile was investigated. A wide range of characterization techniques was employed, including X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), grain-size analysis, and thermogravimetric analysis. The wall tile body was prepared by the dry process. The tile pieces were uniaxially pressed and fired between 1080 - 1180 deg C using a fast-firing cycle. The following technological properties were determined: linear shrinkage, water absorption, apparent density, and flexural strength. The development of the microstructure was followed by SEM and XRD analyses. It was found that the 'thin' red clay is kaolinitic type containing a substantial amount of quartz. The results also showed that the 'thin' red clay could be used in the manufacture of wall tiles, as they present properties compatible with those specified for class BIII of ISO 13006 standard. (author)

  20. Endemic and threatened tetrapods in the restingas of the biodiversity corridors of Serra do Mar and of the central da Mata Atlântica in Eastern Brazil

    Directory of Open Access Journals (Sweden)

    C. F. D Rocha

    Full Text Available Biodiversity corridors comprise a mosaic of land uses connecting fragments of natural forest across a landscape. Two such corridors have been established along the eastern coast of Brazil: the Serra do Mar and the Central da Mata Atlântica corridors, along which most of the coastal plains are restinga areas. In this study, we analyze the present status of the endemic and endangered terrestrial vertebrates of both corridors. We sampled 10 restingas in both corridors, recording species of amphibians, reptiles, birds, and mammals. Some restingas harbor a relatively large number of endemic species, and two main regions of endemism can be identified along the restingas of both corridors: the coastal restingas from northern Espírito Santo State to southern Bahia State (between Linhares, ES, and Trancoso, BA, and the coastal region between the restingas of Maricá and Jurubatiba, Rio de Janeiro State. Six species of terrestrial vertebrates considered threatened with extinction are found in the restingas of Serra do Mar and Central da Mata Atlântica biodiversity corridors (Liolaemus lutzae, Formicivora littoralis, Mimus gilvus, Schistochlamys melanopis, and Trinomys eliasi. The region located between the restinga of Maricá and that of Jurubatiba is of special relevance for the conservation of vertebrate species of the restingas of the corridors because a considerable number of threatened species of terrestrial vertebrates are found there. We strongly recommend efforts to develop checklists of threatened faunas for the States of Espírito Santo and Bahia.

  1. Ingestion of solid wastes by juvenile green turtles, Chelonia mydas (L. 1758, in the eastern Rio de Janeiro state coast, Brazil

    Directory of Open Access Journals (Sweden)

    Danielle Rodrigues Awabdi

    2013-03-01

    Full Text Available This paper analyzed the solid wastes of anthropogenic origin obtained from the stomach contents of juvenile green turtles, Chelonia mydas, on the eastern Rio de Janeiro state coast, southeastern Brazil (22º50’S – 23º00’S. Between June 2009 and May 2010, the stomach contents of 49 specimens stranded on beaches were analyzed. Solid wastes were recorded in 29 stomach contents (59.2% and more than one category of wastes was found out in 22 samples. Plastic bags, categorized as flexible plastic materials, achieved the greatest occurrence frequency (96.5%. Perhaps, these wastes came from the disposal of garbage bags, raffia bags, commercial shop bags and various packaging. Wastes related to manufacture of fishing equipment were also often reported, such as nylon yarns, rubber, ropes, Styrofoam, and fishhooks. The region is an area of regular occurrence of C. mydas and the relatively large intake of solid wastes deposited in the environment poses a risk to the conservation of this species.

  2. Does climate influence assemblages of anurans and lizards in a coastal area of north-eastern Brazil?

    Science.gov (United States)

    Rodrigues, João Fabrício Mota; Borges-Leite, Maria Juliana; Borges-Nojosa, Diva Maria

    2016-11-01

    Environmental factors influence diverse assemblage features such as species abundances, richness, and nestedness. Amphibians and reptiles play important roles in terrestrial ecosystems, but there is still a lack of information about the assemblages of these animals in many regions. In this study, we aimed to understand how environmental factors influence the anurans and lizards assemblages from São Gonçalo do Amarante, Ceará, Brazil. Herpetofauna samplings were performed monthly in São Gonçalo do Amarante from January 2008 to May 2009, excluding April 2008. We sampled animals (anurans and lizards) using pitfall traps and active searches. The abundance and richness of lizards were positively related to temperature and negatively related to precipitation. Anuran assemblage was not influenced by precipitation, but its abundance was negatively influenced by temperature. Temperature generated a nested pattern in the lizard assemblage, but precipitation did not produce this pattern in anurans. Finally, our results reinforce the importance of environmental factors, mainly temperature, in structuring assemblages of anurans and lizards.

  3. FOREST LITTER DECOMPOSITION AS AFFECTED BY EUCALYPTUS STAND AGE AND TOPOGRAPHY IN SOUTH-EASTERN BRAZIL1

    Directory of Open Access Journals (Sweden)

    Alba Lucia Araujo Skorupa

    2015-12-01

    Full Text Available Forest litter decomposition is a major process in returning nutrients to soils and thus promoting wood productivity in the humid tropic. This study aimed to assess decomposition of eucalypt litter in the Rio Doce region, Brazil. Leaf litter was sampled under clonal eucalypt stands aged 2, 4 and 6 years on hillslopes and footslopes. Soil and soil+litter samples were incubated at two levels of soil moisture, temperature and fertilization. C-CO2 emissions from soil measured during 106 days were higher at 32 °C than at 23°C, mainly for the 2-yr-old stand on footslope. When leaf litter was added on soils, C-CO2 emissions were eight times higher, mainly on footslopes, with no effect of stand age. Leaf decomposition in situ, assessed with a litterbag experiment showed a mean weight loss of at least 50% during 365 days, reaching 74% for 2 yr-old stands on footslopes. In comparison with data from the native forest and the literature, no apparent restrictions were found in eucalypt litter decomposition. Differences between in vitro and in situ results, and between eucalypt and native forest, were most likely related to the response of diverse decomposer communities and to substrate quality.

  4. Resilience of Amazonian landscapes to agricultural intensification

    NARCIS (Netherlands)

    Jakovac, C.C.

    2015-01-01

    ISBN: 978-94-6257-443-4 Author: Catarina C. Jakovac Title: Resilience of Amazonian landscapes to agricultural intensification Swidden cultivation is the traditional agricultural system in riverine Amazonia, which supports local livelihoods and trans

  5. Composition, structure and floristic diversity in dense rain forest in the Eastern Amazon, Amapá, Brazil

    Directory of Open Access Journals (Sweden)

    Marcelo de Jesus Veiga Carim

    2015-10-01

    Full Text Available This study aims to evaluate the phytosociology and floristic composition of tree species in the eastern Amazon, at the Iratapuru River Sustainable Development Reserve (RDS, State of Amapá. Fouteen quarters with dimensions of 100 m x 100 m were randomly inventoried, and 50 sub-plots of 10 m x 20 m were established. In each sub-plot all living individuals were sampled, being taken from the height data and DAP (breast height diameter for tree species ≥ 10 cm. A total of 5,233 individuals belonging to 33 families and 184 species were registered. The families with the largest number of species were Fabaceae (32, Lauraceae (17, Sapotaceae (12, Moraceae (10, Lecythidaceae (8 and Annonaceae (8. The six most abundant families (18.18% of total families in the present study were responsible for more than half (57.92% of the total number of species. The floristic structure of the area studied was diverse, with species of varied interests, including: medicinal, timber and oil-producing.

  6. Controls of Nazca ridge subduction on the Amazonian foreland basin geometry

    Science.gov (United States)

    Espurt, N.; Baby, P.; Brusset, S.; Roddaz, M.; Hermoza, W.; Regard, V.; Martinod, J.; Bolaños, R.

    2006-12-01

    In the central Andes, the Nazca ridge subduction imprints can be tracked on the eastern side of the Andes. The western part of the Amazonian basin is currently an atypical foreland basin because the Amazonian foreland basin 3-D geometry does not follow the foreland basin system model of DeCelles and Giles [1]. The Amazonian foreland basin consists of two main subsiding basins separated by the NE-SW trending structural/morphologic Fitzcarrald Arch. Geomorphic and lithospheric data provide evidence that the large wavelength Fitzcarrald Arch uplift at 750 kilometers ahead of the trench results from the Nazca ridge flat subduction. The flexure of the South American lithosphere is overcompensated by the buoyancy of the Nazca ridge impeaching a four-component foreland basin system. The recent deformations of the Amazon basin are characterized by vertical motions as recorded by the radial modern drainage network and the deformation of Pliocene to recent fluvial deposits on both sides of the arch, according to the kinematics of the Nazca ridge subduction. In addition, analogue lithospheric experiments similarly show that the ridge buoyancy induces uplift above the flat-slab segment in the foreland basin separating two subsiding sub-basins resulting from the flexure of the continental lithosphere. [1] DeCelles, P.G., and Giles, K.A.(1996)Foreland basin systems: Basin Research, 8, 105-123.

  7. Haematological reference for red-browed parrot ( Amazona rhodocorytha , Salvadori, 1890 captive in the Atlantic Forest in Eastern Brazil

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    R.H. Mello

    Full Text Available ABSTRACT To conduct the survey were used 35 (thirty-five red-browned parrots (A. rhodocorytha, adults, captive, of both genders and clinically healthy, belonging to the live collection of the Museum of Biology Teacher Mello Leitao, located in Santa Teresa, Espírito Santo, Brazil. Harvests were performed in the morning, by puncture of the brachial vein getting 0.5mL of blood stored in EDTA for a period no longer than 6 hours. Blood smears of fresh material were made at collection, stained using the method of May-Grunwald-Giemsa. Analysis of blood elements was done by cell counting in a mirrored Neubauer chamber using Natt and Herrick solution at a ratio of 2:200 as diluent. For the analysis of the methodology, homoglobinometry cyanide hemoglobin using commercial kits by colorimetry on a semi-automatic biochemical analyzer was used. After completion of the statistical data the following parameters were obtained (mean±standard deviation: Erythrocytes (x106/μl: 2.68±0.56; Hemoglobin (g/dl: 14.27±0.69; Hematocrit (%: 53±3.38; Mean corpuscular volume (fl: 206.7±45.82; Mean corpuscular hemoglobin (pg: 56.4±14.46; Mean corpuscular hemoglobin concentration (%: 27.5±1.19; Thrombocytes (x3/μl: 25.8 ± 10.5; Total plasma protein (g/dl 5.4±0.5; Leukocytes (x103/dl: 3.1±2; Heterophile (/uL: 1937±1676; Lymphocytes (/uL: 1144±599; Monocytes (/uL: 24.4 ± 28.2; Basophils (/uL: 42.2±46.2; Eosinophils (/uL: 11.7±19.9. In the relation between males and females, no significant differences were found in any hematological parameter evaluated.

  8. How does the Nazca Ridge subduction influence the modern Amazonian foreland basin?

    Science.gov (United States)

    Espurt, N.; Baby, P.; Brusset, S.; Roddaz, M.; Hermoza, W.; Regard, V.; Antoine, P.-O.; Salas-Gismondi, R.; Bolaños, R.

    2007-06-01

    The subduction of an aseismic ridge has important consequences on the dynamics of the overriding upper plate. In the central Andes, the Nazca Ridge subduction imprint can be tracked on the eastern side of the Andes. The Fitzcarrald arch is the long-wavelength topography response of the Nazca Ridge flat subduction, 750 km inboard of the trench. This uplift is responsible for the atypical three-dimensional shape of the Amazonian foreland basin. The Fitzcarrald arch uplift is no older than Pliocene as constrained by the study of Neogene sediments and geomorphic markers, according to the kinematics of the Nazca Ridge subduction.

  9. Diversity and genetic structure analysis of three Amazonian Amerindian populations of Colombia.

    Science.gov (United States)

    Braga, Yamid; Arias B, Leonardo; Barreto, Guillermo

    2012-04-01

    In the departments of the Vaupés and Guaviare, in southeastern Colombia, in a transitional area between Amazonia and the eastern plains, inhabit indigenous groups belonging to the Tukanoan (East) and Guahiban linguistic families. Although some studies have dealt with the culture and the cosmology description of these groups, little research has been done on the biological diversity and genetic relationships of such groups. To estimate the diversity, the structure, and the genetic relationships of one Guahiban and two Tukanoan groups of the Colombian Amazonian region. Samples were collected (n = 106) from unrelated individuals belonging to the Vaupés native indigenous communities. The DNA was extracted and nine autosomal microsatellites were typed. Several measures of diversity, FST, pairwise FST, and population differentiation between groups were calculated. Finally, it was estimated the genetic distances of the groups studied in relation with other Amazonian, Andean and Central American indigenous people. 1. The genetic diversity found stands within the range of other Amazonian populations, whereas compared to the mestizo and afro-descendant Colombian populations, such diversity showed to be lower. 2. The structure and population differentiation tests showed two clusters; one consisting of the Vaupés Tukanoan and Guaviare Tukanoan groups, and a second one formed by the Guayabero. 3. Tukanoan groups are found to be closer related to the Brazilian Amazonian populations than to the Guayabero. The results of this study suggest that the Guayabero group from Guaviare, are genetically differentiated from those Tukanoan groups of the Vaupés and Guaviare.

  10. Growth of the dolphinfish Coryphaena hippurus from north-eastern Brazil with an appraisal of the efficacy of scales and otoliths for ageing.

    Science.gov (United States)

    Lessa, R; Santana, F M

    2016-07-01

    Age and growth of the dolphinfish Coryphaena hippurus caught off north-eastern Brazil were studied by counting growth increments on scales and otoliths. A sample (n = 2338) measuring 7·7-195 cm fork length (LF ) was collected from September 2001 to February 2003. The scales (n = 69) removed from six different regions of the body were examined and those from the caudal region exhibited greater morphological regularity, symmetry and a smaller rate of regeneration. The regression between caudal scale radius (RS ) and LF displayed was linear (LF  = 28·334 RS  + 9·186; r(2)  = 0·754). Otolith micro-increments were counted assuming daily periodicity. Ages estimated from otoliths ranged from 64 to 659 days. The von Bertalanffy growth model was fitted based on the otolith readings generating L∞  = 194·1 cm LF , k = 0·912 year(-1) and t0  = 0·081 years. Species longevity was estimated to be c. 4 years. Ninety-eight per cent of the overall sample was adult specimens well above the age of first maturity in the study area. The large variability between scale length and LF and the failure to ascertain increment deposition periodicity suggest that scales are not appropriate for ageing C. hippurus and analysis of otolith micro-increments is deemed the best structure for ageing this species in the study area.

  11. Further evidence of 777 Ma subduction-related continental arc magmatism in Eastern Dom Feliciano Belt, southern Brazil: The Chácara das Pedras Orthogneiss

    Science.gov (United States)

    Koester, E.; Porcher, C. C.; Pimentel, M. M.; Fernandes, L. A. D.; Vignol-Lelarge, M. L.; Oliveira, L. D.; Ramos, R. C.

    2016-07-01

    In this study new SHRIMP U-Pb zircon data for the Chácara das Pedras Gneiss in Porto Alegre, southern Brazil are presented. They represent a small exposure of the crust which was intruded by a large volume of orogenic to anorogenic granitoids at ca. 618-562 m.y. in the Eastern Domain of the Dom Feliciano Belt. The Chácara das Pedras tonalitic orthogneiss has geochemical similarities with subduction-related magmatic rocks of continental arcs. They present high Sr initial ratios (∼0.712), negative ɛNd(t = 777) values (∼-6), TDM varying from 1.8 to 2.0 Ga. The igneous protoliths of these orthogneisses were previously considered to be Paleoproterozoic based on an upper intercept age of discordant zircon analyses. In the present study these orthogneisses were re-sampled and re-analyzed in an attempt to obtain more concordant analytical data. The U-Pb zircon analyses were carried out using the SHRIMP IIe at the Laboratório de Geocronologia de Alta Resolução of the Universidade de São Paulo. The U-Pb concordia age obtained for igneous textural domains of the zircon grains is 777 ± 4 Ma. A few analyses on zircon overgrowths give poorly defined late Cryogenian ages of ca. 650 Ma. Older ages, mostly discordant, were obtained in a few zircon cores, showing an upper intercept age of ca. 1.9 Ga. One sample of the Três Figueiras Granodiorite, which crosscut the orthogneiss in the same outcrop, was also investigated. The zircons of this granodiorite are, however, mostly metamitic, preventing the determination of a reliable age. Some concordant analyses from a few grains define ages ranging in the interval between ca. 603 and 1022 Ma. The youngest (ca. 603 Ma) may represent a maximum age for the granodiorite crystallization. Older ages, with discordance Plata and Kalahari cratons.

  12. Identity and relationships of the Arboreal Caatinga among other floristic units of seasonally dry tropical forests (SDTFs) of north-eastern and Central Brazil.

    Science.gov (United States)

    Santos, Rubens M; Oliveira-Filho, Ary T; Eisenlohr, Pedro V; Queiroz, Luciano P; Cardoso, Domingos B O S; Rodal, Maria J N

    2012-02-01

    The tree species composition of seasonally dry tropical forests (SDTF) in north-eastern and central Brazil is analyzed to address the following hypotheses: (1) variations in species composition are related to both environment (climate and substrate) and spatial proximity; (2) SDTF floristic units may be recognized based on peculiar composition and environment; and (3) the Arboreal Caatinga, a deciduous forest occurring along the hinterland borders of the Caatinga Domain, is one of these units and its flora is more strongly related to the caatinga vegetation than to outlying forests. The study region is framed by the Brazilian coastline, 50th meridian west and 21st parallel south, including the Caatinga Domain and extensions into the Atlantic Forest and Cerrado Domains. Multivariate and geostatistic analyses were performed on a database containing 16,226 occurrence records of 1332 tree species in 187 georeferenced SDTF areas and respective environmental variables. Tree species composition varied significantly with both environmental variables and spatial proximity. Eight SDTF floristic units were recognized in the region, including the Arboreal Caatinga. In terms of species composition, its tree flora showed a stronger link with that of the Cerrado Dry Forest Enclaves. On the other hand, in terms of species frequency across sample areas, the links were stronger with two other units: Rock Outcrops Caatinga and Agreste and Brejo Dry Forests. There is a role for niche-based control of tree species composition across the SDTFs of the region determined primarily by the availability of ground water across time and secondarily by the amount of soil mineral nutrients. Spatial proximity also contributes significantly to the floristic cohesion of SDTF units suggesting a highly dispersal-limited tree flora. These units should be given the status of eco-regions to help driving the conservation policy regarding the protection of their biodiversity.

  13. Seasonal variation of serum biochemical values of Amazonian snakes (Boa constrictor constrictor kept in captivity

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    Dennis José da Silva Lima

    2012-11-01

    Full Text Available In northern Brazil, the seasons are not well defined compared to the South and Southeast regions, due to a hot and humid equatorial climate with a rainy season, known as the Amazonian winter, and a period with less rain, known as the Amazonian summer. The goal of this study was to evaluate the biochemical variation of serum from the Amazon Boa constrictor by correlating the values with the seasons of the region. A biochemical analysis of the serum was performed (AST, ALT, LDH, ALP, calcium, uric acid, phosphorus, total protein, albumin and globulin using 31 individuals of Boa constrictor constrictor, which were kept in captivity. It was observed that eight of the ten parameters were higher in the winter compared to the summer (total protein, albumin, globulin, ALT, AST, ALP, LDH and calcium. The ALT, AST and calcium values had statistically significant differences for the summer and winter, while the other parameters appear to be influenced by seasonality. This was the first study of snakes kept in captivity that analyzed the serum chemistry profile of Boa constrictor constrictor from the state of Pará, Brazil.

  14. The Amazonian Goblin Spiders of the New Genus Gradunguloonops (Araneae: Oonopidae).

    Science.gov (United States)

    Grismado, Cristian J; Izquierdo, Matías A; González Márquez, María E; Ramírez, Martín J

    2015-03-29

    A new genus of soft-bodied oonopids, Gradunguloonops, is established for a group of goblin spiders found in the Amazonian rainforests of northern South America. Members of this genus differ from other oonopids in that the proclaw of tarsi I and II is notably larger than the corresponding retroclaw, a putative synapomorphy of the group. Gradunguloonops comprises twelve species, all new and described in this contribution: G. mutum (type species) from Brazil and Peru, G. bonaldoi, G. amazonicus, G. urucu, G. pacanari, G. juruti from Brazil, G. erwini from Peru, G. orellana and G. nadineae from Ecuador, G. benavidesae and G. florezi from Colombia, and G. raptor from Venezuela. Two preliminary intrageneric groups are proposed on the basis of their female genital morphology: the bonaldoi group, to which are assigned the species with the anterior section comprising only a single anterior sclerite, and the mutum group, with a more complex, tripartite anterior section.

  15. Observations on some Avian Coccidia (Apicomplexa: Eimeriidae in Amazonian Brazil

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    Ralph Lainson

    1994-09-01

    Full Text Available Oocysts of Eimeria porphyrulae n. sp. are described in faeces of Porphyrula martinica (Aves: Gruiformes: Rallidae. They are ellipsoidal to oval, 22.4 x 17.7 (20.0-23.7 x 16.2-18.7 µm, shape-index (length/width 1.3. Oocyst wall about 1.25 µm thick, colourless, with two layers: inner one prominently striated. Micropyle and sub-micropylar granule present: no oocyst residuum. Sporocysts 17.5 x 9.0 (17.0-19.0 x 8.0-10.0 µm, shape-index 1.9, with inconspicuous Stieda/sub-Stieda bodies. Sporocyst residuum of scattered granules, sometimes a compact mass: sporozoites with two refractile bodies. Eimeria crypturelli n. sp. is described in faeces of Crypturellus soiu (Tinamiformes: Tinamidae. Oocysts ellipsoidal-oval, 20.75 x 14.5 (17.5-25.0 x 11.25-21.25 µm, shape-index 1.4. Oocysts wall about 1.25 µm thick and bi-layered: inner layer faintly striated. Micropyle present, with oocyst residuum immediately below: single polar body rarely present. Sporocysts 13.0 x 7.5 (12.5-13.75 x 7,5-8.1 µm, shape-index 1.7, with a Stieda body but seemingly no sub-Stieda. Sporocyst residuum compact: sporozoites with two refractile bodies. Isospora cacici n. sp. is recorded from faeces of Cacicus cela cela (Passeriformes: Icteridae. Oocysts subspherical-spherical, 26.5 x 23.7 (22.5-27.5 x 20.0-26.2 µm, shape-index 1.1. Wall a single, colourless layer about 1.5 µm thick. No micropyle or oocyst residuum: 1-2 polar bodies. Sporocysts ellipsoidal, 17.7 x 12.5 (17.5-18.75 x 11.25-13.75 µm, shape-index 1.4, with pronounced Stieda/sub-Stieda bodies: residuum compact and sporozoites with two refractile bodies. Isospora thraupis n. sp. is described from faeces of Thraupis palmarum melanoptera (Passeriformes: Thraupidae. Oocysts subspherial-spherical, 19.9 x 19.0 (18.7-21.2 x 18.75-20.0 µm, shape-index 1.0. Wall about 0.6 µm thick, smooth, colourless and a single layer: no micropyle, oocyst residuum or polar bodies. Sporocysts 14.2 x 9.2 (13.7-16.2 x 8.7-10.0 µm, shape-index 1.5: Stied/sub-Stieda bodies inconspicuous. Residuum compact: sporozoites with two refractile bodies.

  16. Ginandromorfo de Arsenura armida (Cramer de Querari, São Gabriel da Cachoeira, Amazonas, Brasil (Lepidoptera, Saturniidae, Arsenurinae Gynandromorph of Arsenura armida (Cramer from Querari, São Gabriel da Cachoeira, Amazonas State, Brazil (Lepidoptera, Saturniidae, Arsenurinae

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    Catarina da Silva Motta

    2000-06-01

    Full Text Available The occurrence of a rare ginandromorph specimen of Saturniidae collected in the State of Amazonas, Brazil is reported. This is the first unique deposit of a gynandromorph in the Collection of the National Institute for Amazonian Research.

  17. Poor prospects for avian biodiversity in Amazonian oil palm.

    Science.gov (United States)

    Lees, Alexander C; Moura, Nárgila G; de Almeida, Arlete Silva; Vieira, Ima C G

    2015-01-01

    Expansion of oil palm plantations across the humid tropics has precipitated massive loss of tropical forest habitats and their associated speciose biotas. Oil palm plantation monocultures have been identified as an emerging threat to Amazonian biodiversity, but there are no quantitative studies exploring the impact of these plantations on the biome's biota. Understanding these impacts is extremely important given the rapid projected expansion of oil palm cultivation in the basin. Here we investigate the biodiversity value of oil palm plantations in comparison with other dominant regional land-uses in Eastern Amazonia. We carried out bird surveys in oil palm plantations of varying ages, primary and secondary forests, and cattle pastures. We found that oil palm plantations retained impoverished avian communities with a similar species composition to pastures and agrarian land-uses and did not offer habitat for most forest-associated species, including restricted range species and species of conservation concern. On the other hand, the forests that the oil palm companies are legally obliged to protect hosted a relatively species-rich community including several globally-threatened bird species. We consider oil palm to be no less detrimental to regional biodiversity than other agricultural land-uses and that political pressure exerted by large landowners to allow oil palm to count as a substitute for native forest vegetation in private landholdings with forest restoration deficits would have dire consequences for regional biodiversity.

  18. Surto de encefalomielite equina Leste na Ilha de Marajó, Pará Eastern equine encephalitis on Marajó Island, Pará state, Brazil

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    Karinny F. Campos

    2013-04-01

    Full Text Available Nove casos de encefalomielite equina foram estudados na Ilha de Marajó, estado do Pará, Brasil. Os equinos apresentavam dificuldade em se manter em estação, andavam em círculo, tinham acentuada depressão, pálpebras cerradas, paralisia da língua, tremores musculares, bruxismo, anorexia e desidratação. Alguns apresentavam diminuição dos reflexos auricular, palpebral, de ameaça, diminuição do tônus da língua e taquicardia. Posição de auto-auscultação foi observada com frequência. Os animais muitas vezes eram encontrados apoiados em troncos e cercas para se manterem em estação. À necropsia verificou-se hemorragia das leptomeninges e da medula, alguns apresentaram ainda aderência das leptomeninges. À histopatologia verificou-se encefalite difusa que afetava principalmente a substância cinzenta, com meningite e coroidite. Foi observada perivasculite mononuclear. Em dois equinos identificou-se o vírus da encefalomielite equina Leste pela reação de Semi-Nested transcrição reversa de polimerase em cadeia (Semi-Nested RT-PCR.Nine cases of equine encephalomyelitis on Marajó Island, state of Pará, Brazil, were studied. The affected horses had difficulty to stand, walked in circles, with marked depression, closed eyelids, tongue paralysis, muscle tremors, bruxism, anorexia and dehydration. Some had their ear and eyelid reflexes diminished, decreased tongue tone and tachycardia; laid down frequently they kept their head on the chest. Often they were seen resting their head on tree trunks or fences. At necropsy, hemorrhages of the meninges and spinal cord, and in some animals also adhesion of the meninges were found. Histologically there was diffuse encephalitis affecting mainly the gray matter, with meningitis and choroiditis. Presence of perivascular cuffs consisting of mononuclear inflammatory cells was observed. From two horses the Eastern equine encephalitis virus was identified by semi-nested reverse transcription

  19. Voices of Contact: Politics of Language in Urban Amazonian Ecuador

    Science.gov (United States)

    Wroblewski, Michael

    2010-01-01

    This dissertation is a study of diverse linguistic resources and contentious identity politics among indigenous Amazonian Kichwas in the city of Tena, Ecuador. Tena is a rapidly developing Amazonian provincial capital city with a long history of interethnic and interlinguistic contact. In recent decades, the course of indigenous Kichwa identity…

  20. Changes in the blood parameters of the Amazonian manatee (Trichechus inunguis after long-distance transportation - doi: 10.4025/actascibiolsci.v35i4.20081

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    Talita Laurie Lustosa do Carmo

    2013-07-01

    Full Text Available In this study we report the hematological, biochemical and hormonal parameters in a juvenile male Amazonian manatee measured before transport, immediately after transport, and during adaptation to a new facility. The animal was transported from Manaus, Amazonas, Brazil, to São Paulo, São Paulo, Brazil, (2,733 km within 6 hours. Among all blood parameters analyzed, we observed obvious neutrophilia, lymphopenia, and increases in the neutrophil/lymphocyte ratio and serum glucose and aspartate aminotransferase (AST levels, but these parameters subsequently returned to normal. These results suggest that transport and changes in the environment are temporary stressful events for Amazonian manatees. We, therefore, recommend monitoring the hematological and biochemical parameters before and after translocation to minimize the effects of handling stressors in this species

  1. A radio tracking study of home range and movements of the marsupial Micoureus demerarae (Thomas (Mammalia, Didelphidae in the Atlantic forest of south-eastern Brazil

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    Edsel Amorim Moraes Junior

    2005-03-01

    Full Text Available From August 2001 to July 2002 the home range and movements of seven Micoureus demerarae (Thomas, 1905 (three males and four females were investigated using radio tracking in the União Biological Reserve, state of Rio de Janeiro, south-eastern Brazil. A total of 436 locations was obtained and home range estimated with fixed Kernel (95% of data points, and minimum convex polygon (MCP methods, with 100 and 95% of data points. Male home ranges estimated by MCP (100% ranged from 5.4-24.2 ha and females from 0.3-10.7 ha. Corresponding figures calculated with Kernel (95% were 4-10.9 ha for males and 1.3-5.9 ha for females. Animals travelled on average 423 m/night, with males travelling significantly further (582.8 m/night than females (335.1 m/night (t test, t = 3.609, p = 0.001. We concluded that radio tracking produced much larger home ranges than those estimated with traditional live-trapping techniques, suggesting that the latter might underestimate ranging when the area covered with traps is relatively small (ca. 1 ha or less. Radio tracking also indicated that M. demerarae, although predominantly arboreal and weighting only ca. 130 g., has movements similar in magnitude to larger-sized terrestrial didelphimorph marsupials, such as Didelphis Linnaeus, 1758, Philander Linnaeus, 1758 and Metachirus (Desmarest, 1817.No período de agosto de 2001 a julho de 2002 a área de uso e o movimento de sete Micoureus demerarae (Thomas, 1905 (três machos e quatro fêmeas foram acompanhados, através de rádio-telemetria, na Reserva Biológica União, Rio de Janeiro, sudeste do Brasil. Foi obtido um total de 436 localizações e estimou-se a área de uso através dos métodos Kernel fixo (95% das localizações e polígono mínimo convexo (PMC, com 100 e 95% das localizações. A área de uso dos machos estimada pelo PMC (100% variou de 5,4-24,2 ha e fêmeas de 0,3-10,7 ha. Áreas calculadas com Kernel (95% foram 4-10,9 ha para machos e 1,3-5,9 ha para f

  2. Hyperdominance in Amazonian forest carbon cycling

    Science.gov (United States)

    Fauset, Sophie; Johnson, Michelle O.; Gloor, Manuel; Baker, Timothy R.; Monteagudo M., Abel; Brienen, Roel J.W.; Feldpausch, Ted R.; Lopez-Gonzalez, Gabriela; Malhi, Yadvinder; ter Steege, Hans; Pitman, Nigel C.A.; Baraloto, Christopher; Engel, Julien; Pétronelli, Pascal; Andrade, Ana; Camargo, José Luís C.; Laurance, Susan G.W.; Laurance, William F.; Chave, Jerôme; Allie, Elodie; Vargas, Percy Núñez; Terborgh, John W.; Ruokolainen, Kalle; Silveira, Marcos; Aymard C., Gerardo A.; Arroyo, Luzmila; Bonal, Damien; Ramirez-Angulo, Hirma; Araujo-Murakami, Alejandro; Neill, David; Hérault, Bruno; Dourdain, Aurélie; Torres-Lezama, Armando; Marimon, Beatriz S.; Salomão, Rafael P.; Comiskey, James A.; Réjou-Méchain, Maxime; Toledo, Marisol; Licona, Juan Carlos; Alarcón, Alfredo; Prieto, Adriana; Rudas, Agustín; van der Meer, Peter J.; Killeen, Timothy J.; Marimon Junior, Ben-Hur; Poorter, Lourens; Boot, Rene G.A.; Stergios, Basil; Torre, Emilio Vilanova; Costa, Flávia R.C.; Levis, Carolina; Schietti, Juliana; Souza, Priscila; Groot, Nikée; Arets, Eric; Moscoso, Victor Chama; Castro, Wendeson; Coronado, Euridice N. Honorio; Peña-Claros, Marielos; Stahl, Clement; Barroso, Jorcely; Talbot, Joey; Vieira, Ima Célia Guimarães; van der Heijden, Geertje; Thomas, Raquel; Vos, Vincent A.; Almeida, Everton C.; Davila, Esteban Álvarez; Aragão, Luiz E.O.C.; Erwin, Terry L.; Morandi, Paulo S.; de Oliveira, Edmar Almeida; Valadão, Marco B.X.; Zagt, Roderick J.; van der Hout, Peter; Loayza, Patricia Alvarez; Pipoly, John J.; Wang, Ophelia; Alexiades, Miguel; Cerón, Carlos E.; Huamantupa-Chuquimaco, Isau; Di Fiore, Anthony; Peacock, Julie; Camacho, Nadir C. Pallqui; Umetsu, Ricardo K.; de Camargo, Plínio Barbosa; Burnham, Robyn J.; Herrera, Rafael; Quesada, Carlos A.; Stropp, Juliana; Vieira, Simone A.; Steininger, Marc; Rodríguez, Carlos Reynel; Restrepo, Zorayda; Muelbert, Adriane Esquivel; Lewis, Simon L.; Pickavance, Georgia C.; Phillips, Oliver L.

    2015-01-01

    While Amazonian forests are extraordinarily diverse, the abundance of trees is skewed strongly towards relatively few ‘hyperdominant' species. In addition to their diversity, Amazonian trees are a key component of the global carbon cycle, assimilating and storing more carbon than any other ecosystem on Earth. Here we ask, using a unique data set of 530 forest plots, if the functions of storing and producing woody carbon are concentrated in a small number of tree species, whether the most abundant species also dominate carbon cycling, and whether dominant species are characterized by specific functional traits. We find that dominance of forest function is even more concentrated in a few species than is dominance of tree abundance, with only ≈1% of Amazon tree species responsible for 50% of carbon storage and productivity. Although those species that contribute most to biomass and productivity are often abundant, species maximum size is also influential, while the identity and ranking of dominant species varies by function and by region. PMID:25919449

  3. Land use intensity trajectories on Amazonian pastures derived from Landsat time series

    Science.gov (United States)

    Rufin, Philippe; Müller, Hannes; Pflugmacher, Dirk; Hostert, Patrick

    2015-09-01

    Monitoring changes in land use intensity of grazing systems in the Amazon is an important prerequisite to study the complex political and socio-economic forces driving Amazonian deforestation. Remote sensing offers the potential to map pasture vegetation over large areas, but mapping pasture conditions consistently through time is not a trivial task because of seasonal changes associated with phenology and data gaps from clouds and cloud shadows. In this study, we tested spectral-temporal metrics derived from intra-annual Landsat time series to distinguish between grass-dominated and woody pastures. The abundance of woody vegetation on pastures is an indicator for management intensity, since the duration and intensity of land use steer secondary succession rates, apart from climate and soil conditions. We used the developed Landsat-based metrics to analyze pasture intensity trajectories between 1985 and 2012 in Novo Progresso, Brazil, finding that woody vegetation cover generally decreased after four to ten years of grazing activity. Pastures established in the 80s and early 90s showed a higher fraction of woody vegetation during their initial land use history than pastures established in the early 2000s. Historic intensity trajectories suggested a trend towards more intensive land use in the last decade, which aligns well with regional environmental policies and market dynamics. This study demonstrates the potential of dense Landsat time series to monitor land-use intensification on Amazonian pastures.

  4. Long-term landscape change and bird abundance in Amazonian rainforest fragments.

    Science.gov (United States)

    Stouffer, Philip C; Bierregaard, Richard O; Strong, Cheryl; Lovejoy, Thomas E

    2006-08-01

    The rainforests of the Amazon basin are being cut by humans at a rate >20,000 km2/year leading to smaller and more isolated patches of forest, with remaining fragments often in the range of 1-100 ha. We analyzed samples of understory birds collected over 20 years from a standardized mist-netting program in 1- to 100-ha rainforest fragments in a dynamic Amazonian landscape near Manaus, Brazil. Across bird guilds, the condition of second growth immediately surrounding fragments was often as important as fragment size or local forest cover in explaining variation in abundance. Some fragments surrounded by 100 m of open pasture showed reductions in insectivorous bird abundance of over 95%, even in landscapes dominated by continuous forest and old second growth. These extreme reductions may be typical throughout Amazonia in small (rainforest. Abundance for some guilds returned to preisolation levels in 10- and 100-ha fragments connected to continuous forest by 20-year-old second growth. Our results show that the consequences of Amazonian forest loss cannot be accurately described without explicit consideration of vegetation dynamics in matrix habitat. Any dichotomous classification of the landscape into 'forest" and "nonforest" misses essential information about the matrix.

  5. Acute necrotizing colitis with pneumatosis intestinalis in an Amazonian manatee calf.

    Science.gov (United States)

    Guerra Neto, Guilherme; Galvão Bueno, Marina; Silveira Silva, Rodrigo Otavio; Faria Lobato, Francisco Carlos; Plácido Guimarães, Juliana; Bossart, Gregory D; Marmontel, Miriam

    2016-08-09

    On 25 January 2014, a 1 mo old female Amazonian manatee Trichechus inunguis calf weighing 12 kg was rescued by air transport in Guajará, Brazil, and transferred to Mamirauá Institute's Community-based Amazonian Manatee Rehabilitation Center. The calf presented piercing/cutting lesions on the back, neck, and head, in addition to dehydration and intermittent involuntary buoyancy. X-ray analysis revealed a large amount of gases in the gastrointestinal tract. Daily procedures included wound cleaning and dressing, clinical and laboratory monitoring, treatment for intestinal tympanism, and artificial feeding. Adaptation to the nursing formula included 2 kinds of whole milk. Up to 20 d post-rescue the calf presented appetite, was active, and gained weight progressively. Past this period the calf started losing weight and presented constant involuntary buoyancy and died after 41 d in rehabilitation. The major findings at necropsy were pneumatosis intestinalis in cecum and colon, pulmonary edema, and hepatomegaly. The microscopic examination revealed pyogranulomatous and necrohemohrragic colitis with multinucleated giant cells, acute multifocal lymphadenitis with lymphoid depletion in cortical and paramedullary regions of mesenteric lymph nodes, and diffuse severe acinar atrophy of the pancreas. Anaerobic cultures of fragments of cecum and colon revealed colonies genotyped as Clostridium perfringens type A. We speculate that compromised immunity, thermoregulatory failure, and intolerance to artificial diet may have been contributing factors to the infection, leading to enterotoxemia and death.

  6. Preface to special issue: Granite magmatism in Brazil

    Science.gov (United States)

    Janasi, Valdecir de Assis; de Pinho Guimarães, Ignez; Nardi, Lauro Valentim Stoll

    2016-07-01

    Granites are important both to the geologic evolution and to the economy of Brazil. Deposits of precious and rare metals, such as Au, Sn and many others, are directly or indirectly associated with granites, especially in the geologically under-explored Amazon region. On the opposite eastern side of the country, expanding exploitation of natural granite as dimension stone makes Brazil currently the world's second largest exporter of granite blocks. Granites are a major constituent of the Brazilian Archean-Proterozoic cratonic domains (the Amazon and São Francisco cratons) and their surrounding Neoproterozoic fold belts. The granites are thus fundamental markers of the major events of crustal generation and recycling that shaped the South American Platform. As a result, Brazilian granites have received great attention from the national and international community, and a number of influential meetings focused on the study of granites were held in the country in the last three decades. These meetings include the two International Symposia on Granites and Associated Mineralization (Salvador, January 21-31, 1987, and August 24-29, 1997), the Symposium on Rapakivi Granites and Related Rocks (Belém, August 2-5, 1995) and the Symposium on Magmatism, Crustal Evolution, and Metallogenesis of the Amazonian Craton (Belém, August 2006). Special issues dedicated to contributions presented at these meetings in the Journal of South American Earth Sciences (Sial et al., 1998), Lithos (Stephens et al., 1999), Canadian Mineralogist (Dall'Agnol and Ramo, 2006), Precambrian Research (Ramo et al., 2002) and Anais da Academia Brasileira de Ciências (Dall'Agnol and Bettencourt, 1997; Sial et al., 1999a) are still important references on the knowledge of Brazilian granites and granite petrology in general.

  7. Ecology of parasites of Metynnis lippincottianus (Characiformes: Serrasalmidae from the eastern Amazon region, Macapá, State of Amapá, Brazil

    Directory of Open Access Journals (Sweden)

    Maria Danielle Figueiredo Guimarães Hoshino

    2014-05-01

    Full Text Available The present study provides the first investigation on the ecological aspects of the parasites M. lippincottianusfrom the Amazonian basin, as well as the parasite-host relationship. 76 out of the examined fish (98.7% were parasitized by at least one species of parasites. A total of 8,774 parasites were collected, being Ichthyophthirius multifiliis, Anacanthorus jegui, Dadayius pacupeva, Digenea gen. sp. (metacercariae, Procamallanus (Spirocamallanus inopinatus, Procamallanus (Spirocamallanus sp., Spinoxyuris oxydoras, Contracaecum sp. larvae, Dolops longicauda and Hirudinea gen. sp. Ichthyophthirius multifiliis was the dominant species, followed by A. jegui. Among the endoparasites, S. oxydoras and D. pacupeva were predominant. The mean diversity of parasites was HB = 0.96 ± 0.32 and there was aggregate distribution pattern. A positive correlation of body weight with the abundance of I. multifiliis and S. Oxydoras was observed, whereas a negative correlation of body weight with abundance of the Contracaecum sp. larvae was found. The relative condition factor (Kn was not negatively affected by parasites, and a positive correlation between Kn and abundance of I. multifiliis, S. oxydoras and D. pacupeva was found. This study is the first one to record I. multifiliis, D. longicauda and A. jegui parasitizing M. lippincottianus, as well as the first record of D. pacupeva and S. oxydoras in the Amazonas river system.

  8. Molecular surveillance of the Newcastle disease virus in domestic and wild birds on the North Eastern Coast and Amazon biome of Brazil

    Directory of Open Access Journals (Sweden)

    LM Thomazelli

    2012-03-01

    Full Text Available Brazil is one of the world's largest countries with a rich diversity of wildlife, including resident and migratory wild birds, which may be natural reservoirs of the Newcastle disease virus (NDV. Because Brazil is a major global exporter of chicken meat, the emergence of such a disease may have a huge negative impact not only on the economy due to trade restrictions and embargoes, but also on the quality of life of the population. Samples were collected from 1,022 asymptomatic domestic and wild birds from the Brazilian coast and the Amazon region using tracheal/cloacal swabs and tested by RT-qPCR. The results showed 7 (0.7% birds were positive for NDV. The positive samples were then isolated in embryonated chicken eggs and their matrix protein genes were partially sequenced, revealing a low-pathogenicity NDV. This study confirms the maintenance of the velogenic-NDV free status of Brazil.

  9. New Brazilian Cerambycidae from the Amazonian region (Coleoptera)

    Science.gov (United States)

    Santos-Silva, Antonio; Galileo, Maria Helena M.

    2016-01-01

    Abstract Three new species of Cerambycidae are described from the Brazilian Amazonian region: Psapharochrus bezarki (Lamiinae, Acanthoderini); Xenofrea ayri (Lamiinae, Xenofreini); and Mecometopus wappesi (Cerambycinae, Clytini). Mecometopus wappesi is added to a previous key. PMID:27551200

  10. The association of genetic markers and malaria infection in the Brazilian Western Amazonian region

    Directory of Open Access Journals (Sweden)

    B Beiguelman

    2003-06-01

    Full Text Available Almost all individuals (182 belonging to an Amazonian riverine population (Portuchuelo, RO, Brazil were investigated for ascertaining data on epidemiological aspects of malaria. Thirteen genetic blood polymorphisms were investigated (ABO, MNSs, Rh, Kell, and Duffy systems, haptoglobins, hemoglobins, and the enzymes glucose-6-phosphate dehydrogenase, glyoxalase, phosphoglucomutase, carbonic anhydrase, red cell acid phosphatase, and esterase D. The results indicated that the Duffy system is associated with susceptibility to malaria, as observed in other endemic areas. Moreover, suggestions also arose indicating that the EsD and Rh loci may be significantly associated with resistance to malaria. If statistical type II errors and sample stratification could be ruled out, hypotheses on the existence of a causal mechanism or an unknown closely linked locus involved in susceptibility to malaria infection may explain the present findings.

  11. A Synopsis of Sloanea (Elaeocarpaceae in the Neotropical extra-Amazonian Region

    Directory of Open Access Journals (Sweden)

    Daniela Sampaio

    2016-01-01

    Full Text Available ABSTRACT The genus Sloanea is comprised of 150 species, of which about 50 occur in Brazil among several vegetation types but mainly the Amazon and Atlantic forests. The present work provides a synopsis of the Neotropical species of Sloanea in the extra-Amazonian region based on a recent revision of the genus. In general, morphologically Sloanea comprises large trees endowed with buttressed roots; simple leaves; flowers with sepals that may or may not cover the reproductive organs in pre-anthesis phases; stamens with the connective prolonged into an awn that is acuminate, acute or aristate and fruit covered with rigid or flexible bristles or sometimes unarmed. This synopsis describes 17 species, and provides an identification key, illustrations and comments on their diagnostic characters, geographical distribution and main bibliographic references.

  12. Proterozoic granitoids of the Amazonian craton

    Science.gov (United States)

    dalĺAgnol, R.; Costi, H. T.; Lamarão, C. N.; Teixeira, N. P.; Bettencourt, J. S.; Fraga, L. M.

    2003-04-01

    Proterozoic granitoids are widespread in all provinces of the Amazonian craton. In the Maroni-Itacaiunas Province, granitoids associated with the Trans-Amazonian event include: subduction related, 2.16 to 2.14 Ga, calc-alkaline tonalites and trondhjemites; 2.10 to 2.08 Ga, syncolisional potassic granites; 2.05 Ga, charnockites. In the Tapajós Province, ˜2.01 Ga, tonalites are followed by ˜2.0 Ga volcanic sequences and ˜1.98 to 1.96 Ga calc-alkaline granitoids. A reappraisal of magmatic activity occurred at ˜1.88 Ga when calc-alkaline granitoids, as well as subalkaline, A-type granites, associated with felsic volcanic sequences were formed. A similar picture is observed in the northern Roraima region, where post-collisional 2.0 to 1.96 Ga calc-alkaline granitoids and associated volcanic sequences are followed by 1.92 Ga A-type granites. The remarkable 1.88 Ga magmatic event has a continental scale and is related to an extensional tectonism. It affected also the Archean Carajás Province, where, at this time, within-plate, shallow-level, A-type granites were emplaced. Coeval intermediate to felsic volcanic sequences are widespread in the Central Amazonian Province. In the Pitinga region, these sequences are intruded by ˜1.82 Ga, tin-mineralized granites. In the Central Guiana Belt and in the northwestern domains of the Guiana shield ˜1.55 Ga rapakivi complexes, locally with associated anorthosites and mangerites, are common. In the Rio Negro Province, 1.8 to 1.60 calc-alkaline (?) granitoids and gneisses are dominant. They are followed by 1.55 to 1.52 Ga, oxidized, titanite-bearing A-type granites and S-type, two-mica granites. The evolution of the southwestern part of the Amazonian craton is characterized by the occurrence of successive tectonic events extending from ˜1.75 Ga to ˜1.0 Ga. The oldest granitoids are dominantly calc-alkaline tonalites, trondhjemites and granodiorites. However, the Rondonia region is marked by the occurrence of 1.6 to 1.0 Ga old

  13. Small Glaciofluvial Valleys on Amazonian Mars

    Science.gov (United States)

    Fassett, C.; Dickson, J.; Head, J. W.; Levy, J. S.; Marchant, D. R.

    2009-12-01

    We present new observations of small valleys associated with glacial features in the Martian mid-latitudes, based on a survey of images from the Context Camera (CTX) on the Mars Reconnaissance Orbiter. These valleys are small (~50-400 m wide) and short (mechanism most likely to explain their origin is top-down melting of these cold-based glaciers. Some valleys have associated sedimentary deposits (small fans) (e.g., Fig. 1). Both stratigraphic relations and crater counting constrain most such valleys to the Amazonian period. The observed glaciofluvial valleys are typically on slopes of P16_007256_1383). The valley begins in a small alcove, where remnant glacial materials are now ~1 km from the valley head. The valley is ~5.5 km long, has an average slope of 5°, and terminates in an elongate fan.

  14. Placentation in the Amazonian manatee (Trichechus inunguis)

    DEFF Research Database (Denmark)

    Carter, A M; Miglino, M A; Ambrosio, C E;

    2008-01-01

    Evidence from several sources supports a close phylogenetic relationship between elephants and sirenians. To explore whether this was reflected in similar placentation, we examined eight delivered placentae from the Amazonian manatee using light microscopy and immunohistochemistry. In addition......, the fetal placental circulation was described by scanning electron microscopy of vessel casts. The manatee placenta was zonary and endotheliochorial, like that of the elephant. The interhaemal barrier comprised maternal endothelium, cytotrophoblasts and fetal endothelium. We found columnar trophoblast...... beneath the chorionic plate and lining lacunae in this region, but there was no trace in the term placenta of haemophagous activity. The gross anatomy of the cord and fetal membranes was consistent with previous descriptions and included a four-chambered allantoic sac, as also found in the elephant...

  15. The Open University System of Brazil: A Study of Learner Support Facilities in the Northern, North-Eastern and Southern Regions

    Science.gov (United States)

    Da Cruz Duran, Maria Renata; Da Costa, Celso José; Amiel, Tel

    2014-01-01

    Since June 2011, research on the Open University System of Brazil's (UAB's) official evaluation processes relating to learner support facilities has been carried out by the Teachers' Training, New Information, Communication and Technologies research group, which is linked to the Laboratory of New Technologies for Teaching at…

  16. Barriers in access to healthcare in countries with different health systems. A cross-sectional study in municipalities of central Colombia and north-eastern Brazil.

    Science.gov (United States)

    Garcia-Subirats, Irene; Vargas, Ingrid; Mogollón-Pérez, Amparo Susana; De Paepe, Pierre; da Silva, Maria Rejane Ferreira; Unger, Jean Pierre; Vázquez, María Luisa

    2014-04-01

    There are few comprehensive studies available on barriers encountered from the initial seeking of healthcare through to the resolution of the health problem; in other words, on access in its broad domain. For Colombia and Brazil, countries with different healthcare systems but common stated principles, there have been no such analyses to date. This paper compares factors that influence access in its broad domain in two municipalities of each country, by means of a cross-sectional study based on a survey of a multistage probability sample of people who had had at least one health problem within the last three months (2163 in Colombia and 2155 in Brazil). The results reveal important barriers to healthcare access in both samples, with notable differences between and within countries, once differences in sociodemographic characteristics and health needs are accounted for. In the Colombian study areas, the greatest barriers were encountered in initial access to healthcare and in resolving the problem, and similarly when entering the health service in the Brazilian study areas. Differences can also be detected in the use of services: in Colombia greater geographical and economic barriers and the need for authorization from insurers are more relevant, whereas in Brazil, it is the limited availability of health centres, doctors and drugs that leads to longer waiting times. There are also differences according to enrolment status and insurance scheme in Colombia, and between areas in Brazil. The barriers appear to be related to the Colombian system's segmented, non-universal nature, and to the involvement of insurance companies, and to chronic underfunding of the public system in Brazil. Further research is required, but the results obtained reveal critical points to be tackled by health policies in both countries.

  17. Do species traits determine patterns of wood production in Amazonian forests?

    Directory of Open Access Journals (Sweden)

    T. R. Baker

    2008-09-01

    Full Text Available Understanding the relationships between plant traits and ecosystem properties at large spatial scales is important for predicting how compositional change will affect carbon cycling in tropical forests. Here, we examine the relationships between species wood density, maximum height and wood production for 60 Amazonian forest plots. Firstly, we examine how community-level species traits vary across Amazonia. Average species maximum height and wood density are low in western, compared to eastern, Amazonia and are negatively correlated with aboveground wood productivity and soil fertility. Secondly, we compare biomass growth rates across functional groups defined on the basis of these two traits. In similar size classes, biomass growth rates vary little between trees that differ in wood density and maximum height. However, biomass growth rates are generally higher in western Amazonia across all functional groups. Thirdly, we ask whether the data on the abundance and average biomass growth rates of different functional groups is sufficient to predict the observed, regional-scale pattern of wood productivity. We find that the lower rate of wood production in eastern compared to western Amazonia cannot be estimated on the basis of this information. Overall, these results suggest that the correlations between community-level trait values and wood productivity in Amazonian forests are not causative: direct environmental control of biomass growth rates appears to be the most important driver of wood production at regional scales. This result contrasts with findings for forest biomass where variation in wood density, associated with variation in species composition, is an important driver of regional-scale patterns. Tropical forest wood productivity may therefore be less sensitive than biomass to compositional change that alters community-level averages of these plant traits.

  18. Island vs. countryside biogeography: an examination of how Amazonian birds respond to forest clearing and fragmentation

    Science.gov (United States)

    Jared D. Wolfe; Philip C. Stouffer; Karl Mokross; Luke L. Powell; Marina M. Anciães

    2015-01-01

    Avian diversity in fragmented Amazonian landscapes depends on a balance between extinction and colonization in cleared and disturbed areas. Regenerating forest facilitates bird dispersal within degraded Amazonian landscapes and may tip the balance in favor of persistence in habitat patches. Determining the response of Amazonian birds to fragmentation may be...

  19. Phthalate pollution in an Amazonian rainforest.

    Science.gov (United States)

    Lenoir, Alain; Boulay, Raphaël; Dejean, Alain; Touchard, Axel; Cuvillier-Hot, Virginie

    2016-08-01

    Phthalates are ubiquitous contaminants and endocrine-disrupting chemicals that can become trapped in the cuticles of insects, including ants which were recognized as good bioindicators for such pollution. Because phthalates have been noted in developed countries and because they also have been found in the Arctic, a region isolated from direct anthropogenic influence, we hypothesized that they are widespread. So, we looked for their presence on the cuticle of ants gathered from isolated areas of the Amazonian rainforest and along an anthropogenic gradient of pollution (rainforest vs. road sides vs. cities in French Guiana). Phthalate pollution (mainly di(2-ethylhexyl) phthalate (DEHP)) was higher on ants gathered in cities and along road sides than on those collected in the pristine rainforest, indicating that it follows a human-mediated gradient of disturbance related to the use of plastics and many other products that contain phthalates in urban zones. Their presence varied with the ant species; the cuticle of Solenopsis saevissima traps higher amount of phthalates than that of compared species. However, the presence of phthalates in isolated areas of pristine rainforests suggests that they are associated both with atmospheric particles and in gaseous form and are transported over long distances by wind, resulting in a worldwide diffusion. These findings suggest that there is no such thing as a "pristine" zone.

  20. DNA Metabarcoding of Amazonian Ichthyoplankton Swarms

    Science.gov (United States)

    Maggia, M. E.; Vigouroux, Y.; Renno, J. F.; Duponchelle, F.; Desmarais, E.; Nunez, J.; García-Dávila, C.; Carvajal-Vallejos, F. M.; Paradis, E.; Martin, J. F.; Mariac, C.

    2017-01-01

    Tropical rainforests harbor extraordinary biodiversity. The Amazon basin is thought to hold 30% of all river fish species in the world. Information about the ecology, reproduction, and recruitment of most species is still lacking, thus hampering fisheries management and successful conservation strategies. One of the key understudied issues in the study of population dynamics is recruitment. Fish larval ecology in tropical biomes is still in its infancy owing to identification difficulties. Molecular techniques are very promising tools for the identification of larvae at the species level. However, one of their limits is obtaining individual sequences with large samples of larvae. To facilitate this task, we developed a new method based on the massive parallel sequencing capability of next generation sequencing (NGS) coupled with hybridization capture. We focused on the mitochondrial marker cytochrome oxidase I (COI). The results obtained using the new method were compared with individual larval sequencing. We validated the ability of the method to identify Amazonian catfish larvae at the species level and to estimate the relative abundance of species in batches of larvae. Finally, we applied the method and provided evidence for strong temporal variation in reproductive activity of catfish species in the Ucayalí River in the Peruvian Amazon. This new time and cost effective method enables the acquisition of large datasets, paving the way for a finer understanding of reproductive dynamics and recruitment patterns of tropical fish species, with major implications for fisheries management and conservation. PMID:28095487

  1. Amazonian Vegetable Oils and Fats: Fast Typification and Quality Control via Triacylglycerol (TAG) Profiles from Dry Matrix-Assisted Laser Desorption/Ionization Time-of-Flight (MALDI-TOF) Mass Spectrometry Fingerprinting

    OpenAIRE

    Saraiva, Sergio A.; Cabral, Elaine C; Eberlin, Marcos N; Rodrigo R. Catharino

    2009-01-01

    Amazonian oils and fats display unique triacylglycerol (TAG) profiles and, because of their economic importance as renewable raw materials and use by the cosmetic and food industries, are often subject to adulteration and forgery. Representative samples of these oils (andiroba, Brazil nut, buriti, and passion fruit) and fats (cupuacu, murumuru, and ucuba) were characterized without pre-separation or derivatization via dry (solvent-free) matrix-assisted laser desorption/ionization time-of-flig...

  2. Relação entre a precipitação do leste do Nordeste do Brasil e a temperatura dos oceanos Relationship between the rainfall of the eastern Northeast of Brazil and the ocean temperature

    Directory of Open Access Journals (Sweden)

    Geber B. de A. Moura

    2009-08-01

    Full Text Available O objetivo deste trabalho foi correlacionar a precipitação (março a julho de um grupo de postos homogêneos do setor leste do Nordeste do Brasil (NEB com Anomalia de Temperatura da Superfície do Mar (ATSM e identificar áreas de influência deste parâmetro nas chuvas da região. O período de estudo foi de 1945 a 1985 e a análise mostrou influência do Atlântico e Pacífico sobre as chuvas do setor leste, sendo a correlação do Atlântico maior, principalmente na área do Dipolo (correlação maior que 0,6, significativa a p The objective of this work was to correlate the Northeast of Brazil (NEB rainfall grouped in one homogeneous cluster with the global sea surface temperature (SST anomalies. The data covered the period from 1945 to 1985 and the analyses shows that there are influences from the Atlantic and Pacific ocean over the eastern NEB's rainfall, with a higher correlation for the Atlantic, especially in the Dipole area (correlation values greater than 0.6, and p < 0.05. The 1995 Servain and Arnault meridional (Atlantic Dipole and equatorial modes were detected during several lag analyses. In the Eastern Tropical Pacific Ocean in the region of El Niño-3 negative correlations were found, indicating the presence of the descendant branches of the Walker cell in the sector east of the NEB.

  3. Carbon dynamics and ecosystem diversity of Amazonian peatlands

    Energy Technology Data Exchange (ETDEWEB)

    Laehteenoja, O.

    2011-07-01

    The overall aim was to initiate peatland research in Amazonia, which has been referred to as 'one of the large white spots on the global peatland map'. Specifically, the study was to clarify how common peat accumulation is on Amazonian floodplains, and how extensive and thick peat deposits can be encountered. Secondly, the intention was to study how rapidly Amazonian peatlands sequester carbon, and how much carbon they store and thirdly, to gain some understanding of the diversity of peatland ecosystem types and of the processes forming these ecosystems

  4. Soil charcoal as long-term pyrogenic carbon storage in Amazonian seasonal forests.

    Science.gov (United States)

    Turcios, Maryory M; Jaramillo, Margarita M A; do Vale, José F; Fearnside, Philip M; Barbosa, Reinaldo Imbrozio

    2016-01-01

    Forest fires (paleo + modern) have caused charcoal particles to accumulate in the soil vertical profile in Amazonia. This forest compartment is a long-term carbon reservoir with an important role in global carbon balance. Estimates of stocks remain uncertain in forests that have not been altered by deforestation but that have been impacted by understory fires and selective logging. We estimated the stock of pyrogenic carbon derived from charcoal accumulated in the soil profile of seasonal forest fragments impacted by fire and selective logging in the northern portion of Brazilian Amazonia. Sixty-nine soil cores to 1-m depth were collected in 12 forest fragments of different sizes. Charcoal stocks averaged 3.45 ± 2.17 Mg ha(-1) (2.24 ± 1.41 Mg C ha(-1) ). Pyrogenic carbon was not directly related to the size of the forest fragments. This carbon is equivalent to 1.40% (0.25% to 4.04%) of the carbon stocked in aboveground live tree biomass in these fragments. The vertical distribution of pyrogenic carbon indicates an exponential model, where the 0-30 cm depth range has 60% of the total stored. The total area of Brazil's Amazonian seasonal forests and ecotones not altered by deforestation implies 65-286 Tg of pyrogenic carbon accumulated along the soil vertical profile. This is 1.2-2.3 times the total amount of residual pyrogenic carbon formed by biomass burning worldwide in 1 year. Our analysis suggests that the accumulated charcoal in the soil vertical profile in Amazonian forests is a substantial pyrogenic carbon pool that needs to be considered in global carbon models.

  5. On the vertical distribution of smoke in the Amazonian atmosphere during the dry season

    Science.gov (United States)

    Marenco, Franco; Johnson, Ben; Langridge, Justin M.; Mulcahy, Jane; Benedetti, Angela; Remy, Samuel; Jones, Luke; Szpek, Kate; Haywood, Jim; Longo, Karla; Artaxo, Paulo

    2016-02-01

    Lidar observations of smoke aerosols have been analysed from six flights of the Facility for Airborne Atmospheric Measurements BAe-146 research aircraft over Brazil during the biomass burning season (September 2012). A large aerosol optical depth (AOD) was observed, typically ranging 0.4-0.9, along with a typical aerosol extinction coefficient of 100-400 Mm-1. The data highlight the persistent and widespread nature of the Amazonian haze, which had a consistent vertical structure, observed over a large distance ( ˜ 2200 km) during a period of 14 days. Aerosols were found near the surface; but the larger aerosol load was typically found in elevated layers that extended from 1-1.5 to 4-6 km. The measurements have been compared to model predictions with the Met Office Unified Model (MetUM) and the ECMWF-MACC model. The MetUM generally reproduced the vertical structure of the Amazonian haze observed with the lidar. The ECMWF-MACC model was also able to reproduce the general features of smoke plumes albeit with a small overestimation of the AOD. The models did not always capture localised features such as (i) smoke plumes originating from individual fires, and (ii) aerosols in the vicinity of clouds. In both these circumstances, peak extinction coefficients of the order of 1000-1500 Mm-1 and AODs as large as 1-1.8 were encountered, but these features were either underestimated or not captured in the model predictions. Smoke injection heights derived from the Global Fire Assimilation System (GFAS) for the region are compatible with the general height of the aerosol layers.

  6. Combining Taxonomic and Functional Approaches to Unravel the Spatial Distribution of an Amazonian Butterfly Community.

    Science.gov (United States)

    Graça, Márlon B; Morais, José W; Franklin, Elizabeth; Pequeno, Pedro A C L; Souza, Jorge L P; Bueno, Anderson Saldanha

    2016-04-01

    This study investigated the spatial distribution of an Amazonian fruit-feeding butterfly assemblage by linking species taxonomic and functional approaches. We hypothesized that: 1) vegetation richness (i.e., resources) and abundance of insectivorous birds (i.e., predators) should drive changes in butterfly taxonomic composition, 2) larval diet breadth should decrease with increase of plant species richness, 3) small-sized adults should be favored by higher abundance of birds, and 4) communities with eyespot markings should be able to exploit areas with higher predation pressure. Fruit-feeding butterflies were sampled with bait traps and insect nets across 25 km(2) of an Amazonian ombrophilous forest in Brazil. We measured larval diet breadth, adult body size, and wing marking of all butterflies. Our results showed that plant species richness explained most of the variation in butterfly taxonomic turnover. Also, community average diet breadth decreased with increase of plant species richness, which supports our expectations. In contrast, community average body size increased with the abundance of birds, refuting our hypothesis. We detected no influence of environmental gradients on the occurrence of species with eyespot markings. The association between butterfly taxonomic and functional composition points to a mediator role of the functional traits in the environmental filtering of butterflies. The incorporation of the functional approach into the analyses allowed for the detection of relationships that were not observed using a strictly taxonomic perspective and provided an extra insight into comprehending the potential adaptive strategies of butterflies. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Studies on mosquitoes (Diptera: Culicidae and anthropic environment: 9- Synanthropy and epidemiological vector role of Aedes scapularis in South-Eastern Brazil

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1995-06-01

    Full Text Available Behaviour comparisons of Aedes scapularis and Ae. serratus are presented. Results were obtained by sampling Aedes adult mosquitoes at several places in the rural anthropic environment in the Ribeira Valley region of S. Paulo State, Brazil. Aedes dominance was shared by those two species, but Ae. scapularis Sshowed a clear tendency to frequent the modified environment, while Ae. serratus was to be found in the more preserved ones, here represented by the vestigial patchy forests. Regarding the open cultivated land and the dwelling environments, Ae. scapularis preponderates. Considering the regional developmental phases, this mosquito showed a remarkable increase in the modified environment differently from Ae. serratus that underwent a considerable decrease in migrating from the forest to the anthropic environment. As a consequence of these results it is reasonable to conclude that Ae. scapularis may be considered as an epidemiologically efficient vector and that it quite probably played this role in the Rocio encephalitis and other arbovirus epidemics.

  8. Studies on mosquitoes (Diptera: Culicidae and anthropic environment: 9- Synanthropy and epidemiological vector role of Aedes scapularis in South-Eastern Brazil

    Directory of Open Access Journals (Sweden)

    Forattini Oswaldo Paulo

    1995-01-01

    Full Text Available Behaviour comparisons of Aedes scapularis and Ae. serratus are presented. Results were obtained by sampling Aedes adult mosquitoes at several places in the rural anthropic environment in the Ribeira Valley region of S. Paulo State, Brazil. Aedes dominance was shared by those two species, but Ae. scapularis Sshowed a clear tendency to frequent the modified environment, while Ae. serratus was to be found in the more preserved ones, here represented by the vestigial patchy forests. Regarding the open cultivated land and the dwelling environments, Ae. scapularis preponderates. Considering the regional developmental phases, this mosquito showed a remarkable increase in the modified environment differently from Ae. serratus that underwent a considerable decrease in migrating from the forest to the anthropic environment. As a consequence of these results it is reasonable to conclude that Ae. scapularis may be considered as an epidemiologically efficient vector and that it quite probably played this role in the Rocio encephalitis and other arbovirus epidemics.

  9. A new cluster-brood building species of Plebeia (Hymenoptera, Apidae from eastern Brazil Uma nova espécie de Plebeia (Hymenoptera, Apidae do leste do Brasil, com células de cria em cacho

    Directory of Open Access Journals (Sweden)

    Gabriel A. R. Melo

    2009-01-01

    Full Text Available A new species of Plebeia, the second largest genus of stingless bees in the Neotropical region, is described from eastern Brazil. Plebeia grapiuna sp. nov., known only from the lowland forests of southern Bahia, is most similar to P. lucii Moure, a species recently described from Minas Gerais. The lack of yellow marks and the smoother integument of the frons and mesoscutum in P. grapiuna sp. nov. distinguish them. Main features of the nesting habits of the new species are described and illustrated.Uma nova espécie de Plebeia, o segundo maior gênero de meliponíneos na região Neotropical, é descrita do leste do Brasil. Plebeia grapiuna sp. nov., conhecida apenas das florestas de terras baixas do sul da Bahia, é semelhante a P. lucii Moure, uma espécie recentemente descrita de Minas Gerais. A ausência de manchas amarelas e o integumento menos rugoso da fronte e do mesoscuto em P. grapiuna sp. nov. distinguem as duas espécies. Características principais do hábito de nidificação da nova espécie são descritas e ilustradas.

  10. Do species traits determine patterns of wood production in Amazonian forests?

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    T. R. Baker

    2009-02-01

    Full Text Available Understanding the relationships between plant traits and ecosystem properties at large spatial scales is important for predicting how compositional change will affect carbon cycling in tropical forests. In this study, we examine the relationships between species wood density, maximum height and above-ground, coarse wood production of trees ≥10 cm diameter (CWP for 60 Amazonian forest plots. Average species maximum height and wood density are lower in Western than Eastern Amazonia and are negatively correlated with CWP. To test the hypothesis that variation in these traits causes the variation in CWP, we generate plot-level estimates of CWP by resampling the full distribution of tree biomass growth rates whilst maintaining the appropriate tree-diameter and functional-trait distributions for each plot. These estimates are then compared with the observed values. Overall, the estimates do not predict the observed, regional-scale pattern of CWP, suggesting that the variation in community-level trait values does not determine variation in coarse wood productivity in Amazonian forests. Instead, the regional gradient in CWP is caused by higher biomass growth rates across all tree types in Western Amazonia. Therefore, the regional gradient in CWP is driven primarily by environmental factors, rather than the particular functional composition of each stand. These results contrast with previous findings for forest biomass, where variation in wood density, associated with variation in species composition, is an important driver of regional-scale patterns in above-ground biomass. Therefore, in tropical forests, above-ground wood productivity may be less sensitive than biomass to compositional change that alters community-level averages of these plant traits.

  11. Multi-scale comparisons of tree composition in Amazonian terra firme forests

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    L. Freitas Alvarado

    2009-11-01

    Full Text Available We explored the floristic composition of terra firme forests across Amazonia using 55 plots. Firstly, we examined the floristic patterns using both genus- and species-level data and found that the species-level analysis more clearly distinguishes among forests. Next, we compared the variation in plot floristic composition at regional- and continental-scales, and found that average among-pair floristic similarity and its decay with distance behave similarly at regional- and continental-scales. Nevertheless, geographical distance had different effects on floristic similarity within regions at distances <100 km, where north-western and south-western Amazonian regions showed greater floristic variation than plots of central and eastern Amazonia. Finally, we quantified the role of environmental factors and geographical distance for determining variation in floristic composition. A partial Mantel test indicated that while geographical distance appeared to be more important at continental scales, soil fertility was crucial at regional scales within western Amazonia, where areas with similar soil conditions were more likely to share a high number of species. Overall, these results suggest that regional-scale variation in floristic composition can rival continental-scale differences within Amazonian terra firme forests, and that variation in floristic composition at both scales is influenced by geographical distance and environmental factors, such as climate and soil fertility. To fully account for regional-scale variation in continental studies of floristic composition, future floristic studies should focus on forest types poorly represented at regional scales in current datasets, such as terra firme forests with high soil fertility in north-western Amazonia.

  12. Uncovering spatial patterns in the natural and human history of Brazil nut (Bertholletia excelsa) across the Amazon Basin

    NARCIS (Netherlands)

    E. Thomas; C. Alcázar Caicedo; C.H. McMichael; R. Corvera; J. Loo

    2015-01-01

    Aim Our goal was to test the hypothesis that ancient humans substantially contributed to shaping the current distribution of Brazil nut (Bertholletia excelsa), an Amazonian tree species that has been important for human livelihoods since pre-Columbian times. We scrutinized the putative association b

  13. Are Nontimber Forest Products the Antidote to Rainforest Degradation? Brazil Nut Extraction in Madre De Dios, Peru

    NARCIS (Netherlands)

    Escobal, J.A.; Aldana, U.

    2003-01-01

    This study explores the relationship between poverty and Amazonian forest management by Brazil nut harvesters in southeastern Peru. Although the poor rely more upon natural resource-based income than the rich, wealthier households use more forest wood and land than poorer ones. Contrary to the belie

  14. Fungal community assembly in the Amazonian Dark Earth

    NARCIS (Netherlands)

    Reis Lucheta, Adriano; Souza Cannavan, F.S.; Roesch, L.; Tsai, S.M.; Kuramae, E.E.

    2016-01-01

    Here, we compare the fungal community composition and diversity in Amazonian Dark Earth (ADE) and the respective non-anthropogenic origin adjacent (ADJ) soils from four different sites in Brazilian Central Amazon using pyrosequencing of 18S ribosomal RNA (rRNA) gene. Fungal community composition in

  15. Fungal community assembly in the Amazonian Dark Earth

    NARCIS (Netherlands)

    Lucheta, A.R.; Souza Cannavan, F.S.; Roesch, L.; Tsai, S.M.; Kuramae, E.E.

    2016-01-01

    Here, we compare the fungal community composition and diversity in Amazonian Dark Earth (ADE) and the respective non-anthropogenic origin adjacent (ADJ) soils from four different sites in Brazilian Central Amazon using pyrosequencing of 18S ribosomal RNA (rRNA) gene. Fungal community composition in

  16. New species of Monostylis Tulasne (Podostemaceae from the Amazonian region

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    Aldaléa Sprada Tavares

    2015-09-01

    Full Text Available Until now, Monostylis Tulasne (Podostemaceae was considered monospecific, containing only M. capillacea Tulasne. However, recent field expeditions and an analysis of samples from the Amazonian region revealed three new species, Monostylis aripuanensis, M. goeldiana and M. paraensis. The present paper provides detailed morphological descriptions, illustrations, habitat data, comparative taxonomic comments and a dichotomous key to the species.

  17. Towards an understanding of tree diversity in Amazonian forests

    NARCIS (Netherlands)

    Stropp Carneiro, J.

    2011-01-01

    Amazonian forests harbor the highest biodiversity of all terrestrial ecosystems on Earth. The origin of this extraordinary biodiversity and its current distribution are recently becoming better understood. Still, our knowledge of the contribution of processes operating at different temporal and spat

  18. The Amazonian Formative: Crop Domestication and Anthropogenic Soils

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    Manuel Arroyo-Kalin

    2010-03-01

    Full Text Available The emergence of sedentism and agriculture in Amazonia continues to sit uncomfortably within accounts of South American pre-Columbian history. This is partially because deep-seated models were formulated when only ceramic evidence was known, partly because newer data continue to defy simple explanations, and partially because many discussions continue to ignore evidence of pre-Columbian anthropogenic landscape transformations. This paper presents the results of recent geoarchaeological research on Amazonian anthropogenic soils. It advances the argument that properties of two different types of soils, terras pretas and terras mulatas, support their interpretation as correlates of, respectively, past settlement areas and fields where spatially-intensive, organic amendment-reliant cultivation took place. This assessment identifies anthropogenic soil formation as a hallmark of the Amazonian Formative and prompts questions about when similar forms of enrichment first appear in the Amazon basin. The paper reviews evidence for embryonic anthrosol formation to highlight its significance for understanding the domestication of a key Amazonian crop: manioc (Manihot esculenta ssp. esculenta. A model for manioc domestication that incorporates anthropogenic soils outlines some scenarios which link the distribution of its two broader varieties—sweet and bitter manioc—with the widespread appearance of Amazonian anthropogenic dark earths during the first millennium AD.

  19. A Miocene perspective on the evolution of the Amazonian biota

    NARCIS (Netherlands)

    Wesselingh, F.P.; Salo, J.A.

    2006-01-01

    Between c. 23 and 8 Ma, western Amazonia was occupied by the vast Pebas long-lived lake/wetland system. The Pebas system had a variety of influences over the evolution of Miocene and modern Amazonian biota; it formed a barrier for the exchange of terrestrial biota, a pathway for the transition of ma

  20. POLYCHLORINATED DIBENZO-P-DIOXINS, DIBENZOFURANS, AND BIPHENYLS IN FREGATA MAGNIFICENS FROM ILHA GRANDE BAY, RIO DE JANEIRO STATE, SOUTH-EASTERN BRAZIL

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    Aldo Pacheco Ferreira

    2015-03-01

    Full Text Available The purpose of this paper is to perform analyses in a fish-eating seabird species which is recognized to be at risk of accumulating toxic contaminants due to its high position in the trophic web and to its low ability to metabolize xenobiotic compounds. Fregata magnificens were collected at Ilha Grande Bay, Rio de Janeiro, Brazil (23°8'26"S, 44°14'50"W between February, 2009 and April, 2013. Polychlorinated dibenzo-p-dioxins (PCDDs, dibenzofurans (PCDFs, and polychlorinated biphenyls (PCBs, were analyzed in tissue composites, being subsequently identified and quantified using gas chromatography coupled with mass spectrometry. The concentrations were below the range of concern established by World Health Organization. The sum of PCB-congeners analyzed had the concentration of 968 pg/g lipid weight, and 13.9 pg TEQ/g lipid weight. The PCDD/F-congeners analyzed had the concentration of 331.04 pg/g lipid weight, and 13.4 pg TEQ/g lipid weight. This type of study aims to integrate information from analyses of seabirds with halogenated hydrocarbons and could also make contribution to the scientific support for political decisions on coastal zone management.

  1. The petrochemistry of the auriferous, volcanosedimentary Riacho dos Machados Group, Central-eastern Brazil: geotectonic implications for shear-hosted gold mineralization

    Science.gov (United States)

    da Fonseca, E.; Lobato, L. M.; Baars, F. J.

    1997-12-01

    The Ouro Fino Gold Deposit at the Riacho dos Machados Mine is located in the Araçuaí Fold Belt at the eastern margin of the São Francisco Craton. The gold is shear zone-hosted and associated principally with a sulphide-bearing, quartzmuscovite schist, derived from the hydrothermal alteration of pelitic and quartzofeldspathic schists of the Riacho dos Machados Group (RMG). Along the shear zones, mineral associations typical of the amphibolite facies are progressively altered to assemblages typical of the greenschist facies. It has become evident from the studies that the process of segregation and concentration of chemical elements and minerals is the very process of mineralization, involving the concentration of Au. The RMG comprises ultramafic, mafic and acid metavolcanic rocks intercalated in a sequence of metapelites. The metapelites have textures and geochemistry compatible with greywackes. The dacitic and mafic/ultramafic rocks are of calc-alkaline and tholeiitic subalkaline association, respectively. The RMG probably formed within a continental volcanic arc. The thrust faults that establish the regional architecture, and which host the Riacho dos Machados gold mineralization, are related to a continental collision of unknown age between the precursor to the São Francisco Craton and the Guanambi-Correntina Block.

  2. NATOMICAL ASPECTS OF THE PLACENTA FROM ZEBU CATTLE RAISED IN THE ORIENTAL AMAZONIAN, BRAZIL ASPECTOS ANATÓMICOS DE LA PLACENTA DE ZEBUÍNOS CREADO EN EL AMAZÔNIA DEL ESTE ASPECTOS ANATÔMICOS DA PLACENTA DE ZEBUÍNOS CRIADOS NA AMAZÔNIA ORIENTAL, BRASIL.

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    Tânia Vasconcelos Cavalcante

    2009-04-01

    Full Text Available The aim of the present work was to analyze the macroscopic anatomical characteristics of the bovine placenta, Bos taurus indicus, raised in the Oriental Amazonian area accomplishing a profile of these to the regional herd maintained in the Amazonian climatic and environmental conditions. Pregnant uteri of zebu cows were collected in different gestation ages (4 to 8 months. Each uterus was washed in running water and the intercornual ligament was cut, separating the uterine horns. A section along the cervix to the body of the uterus was accomplished. So, the fetal membranes were exposed and they were perforated removing the fetal liquids and the fetus. The piece was inverted to collect the referring morphologic characteristics data. Soon after, it was set in a 10% formalian solution, for subsequent dissection. To the total counting of the placentomes, a pin was placed individually in each structure, repeating the same procedure in both horns. The results for the variables: amount of the placentome and the time of gestation were submitted to statistical analysis. The overall placentomes found in 30 placentas was 2650, varying from an uterine horn to another, with average of 88.33. In the pregnant horn there were 1602 placentomes, with average of 53.40 for placenta (60.45% and in the no pregnant horn there were 1048, with average of 34.93 for placenta (39.55%. Analyzing the placentomes in different pregnant ages it was observed  a gradual increasing in the amount of these, however this increasing variation was not statistically significant (r = 0.2. The placentomes classified as small were predominant mainly in the beginning of pregnancy but the amount decreases in the following months of the pregnancy giving place to the medium and big placentomes. However, that reduction is only statistically significant in the pregnant horn. Most of the observed placentomes were in the oval shaped, independent of the gestation period. Thus, placental

  3. Risk assessment of environmental exposure to mercury in the urban area of Alta Floresta, Mato Grosso State - Amazonian basin - Brazil; Avaliacao do risco potencial para a saude humana da exposicao ao mercurio na area urbana de Alta Floresta, Mato Grosso - Bacia Amazonica - Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Hacon, Sandra de Souza

    1996-07-01

    Mercury contamination in the Amazon basin is a consequence of the intensive and extensive use of metallic Hg in gold mining activities which use the amalgamation process. Mercury vapor is the main form of Hg released in the Amazonian ecosystem. However, some studies have shown that enhanced biotransformation of inorganic mercury into organic Hg is occurring. These two forms of Hg have some properties in common but differ in toxicity and metabolic behavior. Knowledge of the fate and transport of Hg in the Amazon basin is especially important for the assessment of the extent of contamination, as well as the characterization of exposed groups. the present study attempts to evaluate the Hg exposure scenario as well as to assess the quantitative risk (from Hg emission) for workers in gold-dealers' shops and for the general population in the urban area of Alta Floresta. The way that are was populated and the regional and local economy history, particularly in connection with the commercialization of gold in the region, are important factors in the study of the exposure scenario in Alta Floresta. Assessment of exposure pathways has shown that the adult and infant populations of Alta Floresta are exposed to low dose levels of Hg. Fish consumed locally shows high concentrations of Hg, ranging from 0,5 to 3,6 mg/kg. However, due to the low consumption of fish by the general population this exposure pathway has little effect on the health of the general public. Fishermen and their families are those most at risk from Hg intoxication. Workers in gold shops are another critical group, in relation to exposure to Hg vapor. As for the infant population, above 4 years old, inhalation of Hg vapor is the main source of the exposure, one exception being to children of fishermen whose pattern of fish consumption is similar to their parents. These are the two groups at risk from fish ingestion. Infants between 1 and 4 years of age are the group most likely to suffer adverse effects

  4. Studies on mosquitoes (Diptera: Culicidae and anthropic environment: 10- survey of adult behaviour of Culex nigripalpus and other species of Culex (Culex in South-Eastern Brazil

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1995-08-01

    Full Text Available A survey of adult behaviour of Culex (Culex species was carried out from August 1992 through December 1993 in a human modified (anthropic environment in the Ribeira Valley, S.Paulo State, Brazil. Culex nigripalpus dominated the catches at several sites and it's tendency to increase in the anthropic environment became quite clear. Nevertheless no high level of synanthropy was demonstrated. So it seems that the mosquito may have a restricted role in natural arbovirus cycles. Nonetheless, Cx. nigripalpus must be considered a potential vector of arboviruses, especially St. Louis encephalitis virus outside dwellings.São relatados os resultados obtidos mediante coletas regulares de adultos de Culex (Culex em ambientes antrópico do Vale do Ribeira, SP, Brasil, no período de agosto de 1992 a dezembro de 1993. Pôde-se evidenciar a dominancia de Culex nigripalpus nas várias coletas efetuadas. Revelou-se claramente a preferência por parte desse mosquito em aumentar sua densidade no ambiente antrópico. Todavia, sua freqüência ao domicílio mostrou-se baixa, revelando fraco grau de sinantropia. Assim sendo, seu papel vetor de arbovirus parece restringir-se à participação no ciclo natural desses agentes infecciosos. Contudo, pode-se considerá-lo como vetor potencial no meio extradomiciliar. Nesse particular, seu papel pode não ser negligenciável, especialmente no que tange à possibilidade de transmissão de encefalite de S.Luís, cujo agente já foi assinalado na região.

  5. Famennian glaciation in the eastern side of Parnaíba Basin, Brazil: evidence of advance and retreat of glacier in Cabeças Formation

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    Roberto Cesar de Mendonça Barbosa

    Full Text Available ABSTRACTGlaciotectonic features studied in the siliciclastic deposits of Cabeças Formation, Upper Devonian, represent the first evidence of Famennian glaciation in Southeastern Parnaíba Basin, Brazil. Outcrop-based stratigraphic and facies analyses combined with geometric-structural studies of these deposits allowed defining three facies association (FA. They represent the advance-retreat cycle of a glacier. There are: delta front facies association (FA1 composed of massive mudstone, sigmoidal, medium-grained sandstone with cross-bedding and massive conglomerate organized in coarsening- and thickening-upward cycles; subglacial facies association (FA2 with massive, pebbly diamictite (sandstone, mudstone and volcanic pebbles and deformational features, such as intraformational breccia, clastic dikes and sills of diamictite, folds, thrust and normal faults, sandstone pods and detachment surface; and melt-out delta front facies associations (FA3, which include massive or bedded (sigmoidal cross-bedding or parallel bedding sandstones. Three depositional phases can be indicated to Cabeças Formation: installation of a delta system (FA1 supplied by uplifted areas in the Southeastern border of the basin; coastal glacier advance causing tangential substrate shearing and erosion (FA1 in the subglacial zone (FA2, thus developing detachment surface, disruption and rotation of sand beds or pods immersed in a diamicton; and retreat of glaciers accompanied by relative sea level-rise, installation of a high-energy melt-out delta (FA3 and unloading due to ice retreat that generates normal faults, mass landslide, folding and injection dykes and sills. The continuous sea-level rise led to the deposition of fine-grained strata of Longá Formation in the offshore/shoreface transition in the Early Carboniferous.

  6. Palaeohydrological controls on sedimentary organic matter in an Amazon floodplain lake, Lake Maracá (Brazil) during the late Holocene

    NARCIS (Netherlands)

    Moreira, L.S.; Moreira-Turcq, P.; Turcq, B.; Cordeiro, R.C.; Kim, J.-H.; Caquineau, S.; Mandeng-Yogo, M.; Macario, K.D.; Sinninghe Damsté, J.S.

    2013-01-01

    In order to understand the impact of hydrological changes of the Amazon River on sedimentary organic matter (OM) composition in Amazonian floodplain lakes, three sediment cores were collected from Lake Maracá (eastern Amazonia) along a transect from the Amazon River main channel to inland. The cores

  7. Avian gene trees, landscape evolution, and geology: towards a modern synthesis of Amazonian historical biogeography?

    OpenAIRE

    Aleixo, Alexandre Luis Padovan; Rossetti, Dilce de Fátima

    2007-01-01

    Recent studies have improved our understanding of Amazonian geological history during the late Tertiary and Quaternary, two periods regarded as critical for the recent diversification of the Amazonian avifauna. The notion that geologically older and more stable areas of Amazonia (such as the Brazilian and Guianan shields) functioned as ‘‘species-pumps’’, whereas geologically more dynamic areas (such as the western Amazonian lowlands) mostly ‘‘captured’’ part of the div...

  8. Hair mercury levels in Amazonian populations: spatial distribution and trends

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    Barbieri Flavia L

    2009-12-01

    Full Text Available Abstract Background Mercury is present in the Amazonian aquatic environments from both natural and anthropogenic sources. As a consequence, many riverside populations are exposed to methylmercury, a highly toxic organic form of mercury, because of their intense fish consumption. Many studies have analysed this exposure from different approaches since the early nineties. This review aims to systematize the information in spatial distribution, comparing hair mercury levels by studied population and Amazonian river basin, looking for exposure trends. Methods The reviewed papers were selected from scientific databases and online libraries. We included studies with a direct measure of hair mercury concentrations in a sample size larger than 10 people, without considering the objectives, approach of the study or mercury speciation. The results are presented in tables and maps by river basin, displaying hair mercury levels and specifying the studied population and health impact, if any. Results The majority of the studies have been carried out in communities from the central Amazonian regions, particularly on the Tapajós River basin. The results seem quite variable; hair mercury means range from 1.1 to 34.2 μg/g. Most studies did not show any significant difference in hair mercury levels by gender or age. Overall, authors emphasized fish consumption frequency as the main risk factor of exposure. The most studied adverse health effect is by far the neurological performance, especially motricity. However, it is not possible to conclude on the relation between hair mercury levels and health impact in the Amazonian situation because of the relatively small number of studies. Conclusions Hair mercury levels in the Amazonian regions seem to be very heterogenic, depending on several factors. There is no obvious spatial trend and there are many areas that have never been studied. Taking into account the low mercury levels currently handled as acceptable, the

  9. Sequence stratigraphy of Taciba and Rio Bonito formations in Mafra, SC area, eastern Parana Basin, Brazil; Estratigrafia de sequencias das formacoes Taciba e Rio Bonito (Membro Triunfo) na regiao de Mafra/SC, leste da Bacia do Parana

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-05-01

    The Taciba and Rio Bonito ('lower' Triunfo Mbr) formations are divided into six depositional sequences based on cores, gamma-ray and electrical logs from shallow drillings from northern Santa Catarina State, Brazil. Each sequence is formed by two systems tracts, a lower one, sandy (low stand) and an upper one, shaly (high stand). The Taciba Formation has three sequences, S{sub 0} to S{sub 2}; sequence S{sub 0} has a thick turbidite sandstone at the base (Rio Segredo Member) that pinches out towards the eastern margin and even disappears in the Mafra outcrop area. Sequence S{sub 1} varies from a thin fluvial-estuarine system to a thick turbidite sandstone of a channelled fan system; S{sub 1} upper shaly system tract is marine in well PP-11, and it is glacially influenced in well PP-10. Sequence S{sub 2} is a thick sandstone body of shallow marine origin, but restricted to one well (PP-11); its upper shaly tract is dominated by massive siltstones intercalated with thin, distal tempestites. The 'lower' Triunfo Member (or 'Taciba- Triunfo transition') begins with the arrival of deltaic clastics of sequence S{sub 3} lower tract, coarsening-up from medial- to proximal delta front sandstones. Sequence S{sub 4} is quite similar to S{sub 3}, both showing sandstone pro gradation from north to south, as opposed to the southwest-sourced transgressive diamictites. Sequence S{sub 5} consists of fluvial deposits at well PP-12, and two transgressive cycles from wells PP-11 to PP-9, each one of them composed of fluvial-estuarine to marine systems. Well PP-10 is an exception, where the lower cycle presents de glaciation to marine deposits. (author)

  10. Studies on mosquitoes (Diptera: Culicidae and anthropic environment: 9- Synanthropy and epidemiological vector role of Aedes scapularis in South-Eastern Brazil

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1995-06-01

    Full Text Available Behaviour comparisons of Aedes scapularis and Ae. serratus are presented. Results were obtained by sampling Aedes adult mosquitoes at several places in the rural anthropic environment in the Ribeira Valley region of S. Paulo State, Brazil. Aedes dominance was shared by those two species, but Ae. scapularis Sshowed a clear tendency to frequent the modified environment, while Ae. serratus was to be found in the more preserved ones, here represented by the vestigial patchy forests. Regarding the open cultivated land and the dwelling environments, Ae. scapularis preponderates. Considering the regional developmental phases, this mosquito showed a remarkable increase in the modified environment differently from Ae. serratus that underwent a considerable decrease in migrating from the forest to the anthropic environment. As a consequence of these results it is reasonable to conclude that Ae. scapularis may be considered as an epidemiologically efficient vector and that it quite probably played this role in the Rocio encephalitis and other arbovirus epidemics.Relatam-se os resultados de coletas regulares de adultos de culicídeos Aedes, levadas a efeito em ambiente antrópico do Vale do Ribeira, SP, Brasil, ao longo do período de agosto de 1992 a dezembro de 1993. As coletas foram realizadas em várias áreas correspondentes a matas residuais, a ambiente aberto cultivado e a meio domiciliar. A dominância dividiu-se entre Ae. scapularis e Ae. serratus, porém não de maneira equivalente para as diversas áreas pesquisadas. O primeiro revelou nítida tendência ao predomínio no ambiente artificial representado pela área aberta cultivada e pelo domicílio humano. Quanto ao segundo, evidenciou-se nítida preferência pelo meio das matas residuais. Considerando este como remanescente da primitiva cobertura florestal da área, os outros foram tidos como fase posteriormente desenvolvida em virtude da atividade humana. Assim procedendo, compararam-se as

  11. Influence of land use changes on soil physical, chemical and biological atributes in a family farming settlement in Eastern Amazon, Brazil

    Science.gov (United States)

    Cooper, Miguel; de Pierri Castilho, Selene Cristina; Camilo Bedano, José; Dominguez, Anahi; Fernanda Simões da Silva, Laura; Nascimento Delgado Oliveira, Mariana

    2014-05-01

    Soil knowledge and the changes in its attributes due to land use modifications in the Amazon region is important for decision making by family farmers. These farmers have to choose sustainable land use management practices for their survival in the region and, for soil and forest conservation. The study area is located in the Piranheira Praialta Agroextrativist Settlement Project in the county of Nova Ipixuna, Pará, Brazil. The objective of this research is to understand the relations between soil physical, chemical and biological attributes, and how these relations change with modifications in land use. This information is important for defining best management practices for family farming in the region. Two toposequences were chosen, one under native forest and the other under pasture. 40 cm pits were opened with five replicates in three landscape positions (upslope, midslope and downslope). Sampling periods were July/2012 (dry season); January/2013 (beginning of rainy season) and march/2013 (rainy season). Samples were taken for soil particle size analysis, bulk density, particle density, moisture, porosity, water retention, chemical, litter dry matter and macrofauna analysis. Statistical analysis techniques were performed uni and multivariate. No significant differences were observed in the particle size distribution of the studied soils. The soils presented sandy surface horizons with an increase of clay in depth in both land use systems. Soil bulk density values were higher in the surface horizons and, in general, in the pasture toposequence. Differences were also observed in the soil moisture content and litter dry matter which were higher under the native forest, and in the pH and organic matter values which were higher in the pasture. Higher water retention capacity was observed in the surface horizons of the forest when compared to the pasture, corroborating the higher values of macroporosity observed in the forest soils. Due to higher moisture content

  12. A mid-Pleistocene rainforest corridor enabled synchronous invasions of the Atlantic Forest by Amazonian anole lizards.

    Science.gov (United States)

    Prates, Ivan; Rivera, Danielle; Rodrigues, Miguel T; Carnaval, Ana C

    2016-10-01

    Shifts in the geographic distribution of habitats over time can promote dispersal and vicariance, thereby influencing large-scale biogeographic patterns and ecological processes. An example is that of transient corridors of suitable habitat across disjunct but ecologically similar regions, which have been associated with climate change over time. Such connections likely played a role in the assembly of tropical communities, especially within the highly diverse Amazonian and Atlantic rainforests of South America. Although these forests are presently separated by open and dry ecosystems, paleoclimatic and phylogenetic evidence suggest that they have been transiently connected in the past. However, little is known about the timing, magnitude and the distribution of former forest connections. We employ sequence data at multiple loci from three codistributed arboreal lizards (Anolis punctatus, Anolis ortonii and Polychrus marmoratus) to infer the phylogenetic relationships among Amazonian and Atlantic Forest populations and to test alternative historical demographic scenarios of colonization and vicariance using coalescent simulations and approximate Bayesian computation (ABC). Data from the better-sampled Anolis species support colonization of the Atlantic Forest from eastern Amazonia. Hierarchical ABC indicates that the three species colonized the Atlantic Forest synchronously during the mid-Pleistocene. We find support of population bottlenecks associated with founder events in the two Anolis, but not in P. marmoratus, consistently with their distinct ecological tolerances. Our findings support that climatic fluctuations provided key opportunities for dispersal and forest colonization in eastern South America through the cessation of environmental barriers. Evidence of species-specific histories strengthens assertions that biological attributes play a role in responses to shared environmental change.

  13. Amazonian Dark Earths: pathways to sustainable development in tropical rainforests?

    Directory of Open Access Journals (Sweden)

    Morgan Schmidt

    2013-04-01

    Full Text Available Fertile dark anthrosols associated with pre-Columbian settlement across the Amazon Basin have sparked wide interest for their potential contribution to sustainable use and management of tropical soils and ecosystems. In the Upper Xingu region of the southern Amazon, research on archaeological settlements and among contemporary descendant populations provides critical new data on the formation and use of anthrosols. These findings provide a basis for describing the variability of soil modifications that result from diverse human activities and a general model for the formation of Amazonian anthrosols. They underscore the potential for indigenous systems of knowledge and resource management to inform efforts for conservation and sustainable development of Amazonian ecosystems.

  14. Ocorrência de Polypedilum (Tripodura amataura Bidawid-Kafka, 1996 (Diptera; Chironomidae em Aquascypha hydrophora (berk. Reid (Fungi; Stereaceae, com descrição da pupa na Amazônia Central, Brasil Occurrence of Polypedilum (Tripodura amataura Bidawid-Kafka, 1996 (diptera; chironomidae in Aquascypha hydrophora (berk. Reid (Fungi; Stereaceae, with description of the pupae in the Central Amazonian, Brazil

    Directory of Open Access Journals (Sweden)

    Arlindo Serpa-Filho

    2007-01-01

    Full Text Available Quatro larvas foram coletadas em água retida pelo fungo Aquascypha hydrophora (Berk. Reid (Fungi: Stereaceae fixo em troncos de árvores eretas, na Reserva Florestal Adolpho Ducke, Amazonas, Brasil. Das larvas coletadas, apenas um exemplar desenvolveu até a fase adulta, sendo identificado como Polypedilum (Tripodura amataura Bidawid-Kafka, 1996. Esta é a primeira descrição para uma forma imatura deste gênero, e também o primeiro registro em micotelmata.Four larvae were collected in water with the fungus Aquascyphahydrophora (Berk. Reid (Fungi: Stereaceae, fixed in tree trunks found in the Adolpho Ducke Forest Reserve, Amazonas, Brazil. Only one specimem reached the adult phase, which was identified as Polypedilum (Tripodura amataura Bidawid-Kafka, 1996. This is the first description of an immature form of this genus, and also the first registered in mycotelmata.

  15. Plant reproduction in the Central Amazonian floodplains : challenges and adaptations

    OpenAIRE

    Ferreira, Cristiane da Silva; Fernandez Piedade, Maria Teresa; Wittmann, Astrid de Oliveira; Franco, Augusto César

    2010-01-01

    Background The Central Amazonian floodplain forests are subjected to extended periods of flooding and to flooding amplitudes of 10 m or more. The predictability, the length of the flood pulse, the abrupt transition in the environmental conditions along topographic gradients on the banks of major rivers in Central Amazonia, and the powerful water and sediment dynamics impose a strong selective pressure on plant reproduction systems. Scope In this review, we examine how the hydrological cycle i...

  16. Molecular identification of Amazonian stingless bees using polymerase chain reaction single-strand conformation polymorphism.

    Science.gov (United States)

    Souza, M T; Carvalho-Zilse, G A

    2014-07-25

    In countries containing a mega diversity of wildlife, such as Brazil, identifying and characterizing biological diversity is a continuous process for the scientific community, even in face of technological and scientific advances. This activity demands initiatives for the taxonomic identification of highly diverse groups, such as stingless bees, including molecular analysis strategies. This type of bee is distributed in all of the Brazilian states, with the highest species diversity being found in the State of Amazônia. However, the estimated number of species diverges among taxonomists. These bees are considered the main pollinators in the Amazon rainforest, in which they obtain food and shelter; however, their persistence is constantly threatened by deforestation pressure. Hence, it is important to classify the number and abundance of bee specie, to measure their decline and implement meaningful, priority conservation strategies. This study aims to maximize the implementation of more direct, economic and successful techniques for the taxonomic identification of stingless bees. Specifically, the genes 16S rRNA and COI from mitochondrial DNA were used as molecular markers to differentiate 9 species of Amazonian stingless bees based on DNA polymorphism, using the polymerase chain reaction-single-strand conformation polymorphism technique. We registered different, exclusive SSCP haplotypes for both genes in all species analyzed. These results demonstrate that SSCP is a simple and cost-effective technique that is applicable to the molecular identification of stingless bee species.

  17. Phenology, fruit production and seed dispersal of Astrocaryum jauari (Arecaceae) in Amazonian black water floodplains.

    Science.gov (United States)

    Piedade, Maria Teresa F; Parolin, Pia; Junk, Wolfgang J

    2006-12-01

    Astrocaryum jauari Mart. (Arecaceae) is one of the commonest palm species occurring in nutritionally poor Amazonian black water floodplains. It is an emergent or subcanopy tree that grows on river banks and islands, with a wide distribution along the entire flooding gradient, tolerating flood durations between 30 and 340 days. The species is important for fish nutrition in the floodplains, and is also used for hearts of palm. In the present study, the auto-ecology of A. jauari was analysed over a period of two years in the Anavilhanas Archipelago, Rio Negro, Brazil, with a focus on phenology, fruit production, and seed dispersal. Fruit fall is annual and synchronized with high water levels, with a production of 1.6 ton of fruit ha(-1). The fruits are eaten by at least 16 species of fish which either gnaw the pulp, fragment the seed, or ingest the entire fruit, thus acting as dispersal agents. Besides ichthyocory, barochory (with subsequent vegetative propagation) is an important dispersal mode, enhancing the occurrence of large masses of individuals in the Anavilhanas islands and in the region of maximum palm heart extraction near Barcelos.

  18. The production, storage, and flow of carbon in Amazonian forests

    Science.gov (United States)

    Malhi, Yadvinder; Saatchi, Sassan; Girardin, Cecile; Aragão, Luiz E. O. C.

    The carbon stores and dynamics of tropical forests are the subject of major international scientific and policy attention. Research associated with the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) has generated substantial advances in our understanding of the cycling of carbon at selected forest sites in Brazilian Amazonia and generated new insights into how these processes may vary across the wider Amazonian region. Here we report on aspects of this new understanding. We present, in particular, a comprehensive synthesis of carbon cycling in three focal LBA sites (Manaus, Tapajõs, and Caxiuanã), drawing on studies of productivity, litterfall, respiration, physiology, and ecosystem fluxes. These studies are placed in the context of the wider Amazonian region by utilizing the results of the Amazon Forest Inventory Network (RAINFOR) and other forest plots. We discuss the basin-wide distribution of forest biomass derived by combining these plots and a suite of satellite data, and examine the dynamics of carbon cycling in the context of regional carbon stores in the forest. Particular attention is drawn to the strong relationship between forest productivity and turnover, which suggests that higher levels of forest productivity increase forest dynamism rather than forest biomass. We conclude by discussing what the scientific priorities should be for a synthetic region-wide understanding of the carbon dynamics and stores of Amazonian forests.

  19. Food Plants Eaten by Amazonian Manatees (Trichechus inunguis, Mammalia : Sirenia

    Directory of Open Access Journals (Sweden)

    Colares Ioni G.

    2002-01-01

    Full Text Available To determine the feeding habits of the Amazonian manatee Trichechus inunguis in some Central Amazonian rivers and lakes, we compared plant epidermis found in the stomach contents and/or faeces of animals with a reference collection of plants present in the studied areas. Twenty five samples from digestive tracts of animals found dead and 25 faeces samples found floating were analyzed. From these samples, 24 aquatic macrophytes were identified. The Gramineae family was identified in 96% of the samples, Paspalum repens and Echinochloa polystachya being the most abundant in the samples. The second most frequent family was the Pontederiaceae primarily Eichhornia crassipes. During the high water period, the animals showed a more selective diet (eight identified species. In the low water period, when food was more scarce, the animals showed a larger diversity of species in their diet (21 species of plants. Differences in the diet among the two studied areas reflected the physiographics characteristics of the region. Amazonian manatees fed mostly on emergent plants.

  20. Brazils Role in environmental governance: Analysis of possibilities for increased Brazil-Norway cooperation

    Energy Technology Data Exchange (ETDEWEB)

    Valberg, Anna Helene

    2011-07-01

    This report examines the role played by Brazil in connection with certain international negotiations, such as the climate negotiations and the CBD. It identifies the driving factors that have influenced environmental politics and standards in Brazil, and take note of conflicts that must be discussed when Norway is seeking expanded cooperation with Brazil. In line with the mandate, FNI identifies areas of particular interest for further collaboration between the two countries, and recommend directions for supplementary Norwegian policy-making in light of a broadened scope for Norway-Brazil interaction. In recent years, the Norwegian government has initiated an extensive process aimed at reducing emissions from deforestation and forest degradation (REDD). This is the most obvious shared environmental scope between Norway and Brazil. However, given the large body of literature that already exists on this field, this report will concentrate instead on issues more on the outskirts of the REDD discourse, such as biodiversity conservation, biofuel efficiency and challenges concerning hydropower, all of which threaten to impact negatively on the Amazonian areas. In our recommendations, we cite tangible examples to illustrate issues where we believe lessons learnt in Norway may have applicability to Brazil.(auth)

  1. Fish consumption (hair mercury) and nutritional status of Amazonian Amer-Indian children.

    Science.gov (United States)

    Dórea, José G; Barbosa, Antonio C; Ferrari, Iris; De Souza, Jurandir R

    2005-01-01

    Fish are abundant and important dietary items for the Amer-Indians, and total hair-Hg (HHg) concentration is a reliable marker of fish consumption. We studied the impact of fish consumption (HHg) on the nutritional status of Indian children of Eastern Amazonia. Weight-for-height Z score (WHZ) was measured, and HHg was determined in 203 children younger than 10 years of age in three villages. There was significantly higher fish consumption in Kayabi children (16.55 microg Hg/g; SD, 11.44) than in children of the Munduruku villages of Missão-Cururu (4.76 microg Hg/g; SD, 2.09) and Kaburua (2.87 microg Hg/g; SD, 2.13). Anthropometric indices showed WHZ means of -0.27, -0.22, and 0.40, respectively, for Kayabi, Missão-Cururu and Kaburua villages. Despite a different pattern of fish-protein consumption between tribes, there was no significant correlation between WHZ and HHg concentrations (r2 = 0.0079; P < 0.2021). Dietary differences among Amazonian tribes can be traced and used in measuring health outcomes. Higher fish consumption, although important for Kayabis, was compensated by other protein sources by the Kaburua villagers.

  2. Response of frugivorous primates to changes in fruit supply in a northern Amazonian forest.

    Science.gov (United States)

    Mourthé, I

    2014-08-01

    Few attempts have been made to understand how spatiotemporal changes in fruit supply influence frugivores in tropical forests. The marked spatiotemporal variation in fruit supply can affect frugivore abundance and distribution, but studies addressing the effects of this variation on primates are scarce. The present study aimed to investigate how the spatiotemporal distribution of fruits influences the local distribution of three frugivorous primates in the eastern part of the Maracá Ecological Station, a highly seasonal Amazonian rainforest. Specifically, it was hypothesised that primate distribution will track changes in fruit supply, resulting that sites with high fruit availability should be heavily used by primates. During a 1-year study, fruit supply (ground fruit surveys) and primate density (line-transects) were monitored in twelve 2 km-long transects at monthly intervals. Fruit supply varied seasonally, being low during the dry season. The density of Ateles belzebuth was positively related to fruit supply during fruit shortage, but Cebus olivaceus and Alouatta macconnelli did not follow the same pattern. The supply of Sapotaceae fruit was an important component determining local distribution of A. belzebuth during the overall fruit shortage. Highly frugivorous primates such as A. belzebuth respond to seasonal decline in fruit supply by congregating at places with high fruit supply in this forest, particularly, those with many individuals of species of Sapotaceae. This study underscores the importance of small-scale spatiotemporal changes of fruit supply as a key component of frugivorous primate ecology in highly seasonal environments.

  3. Tabanidae (Diptera of Maranhão state, Brazil. V. Description of Protosilvius gurupi sp. n. (Pangoniinae, Pangoniini and key to Protosilvius species

    Directory of Open Access Journals (Sweden)

    Jose Rafael

    2012-10-01

    Full Text Available Protosilvius gurupi sp. n. (Tabanidae, Pangoniinae is described and illustrated based on seven female and 53 male specimens collected in the Amazonian region at Reserva Biológica Gurupi, Centro Novo do Maranhão municipality, northwest Maranhão, Brazil. This is the first record of Protosilvius in northern Brazil and in the Amazon Basin. An illustrated key to all Protosilvius species is also presented.

  4. Tabanidae (Diptera) of Maranhão state, Brazil. V. Description of Protosilvius gurupi sp. n. (Pangoniinae, Pangoniini) and key to Protosilvius species

    Science.gov (United States)

    Rafael, José Albertino; Marques, Dayse Willkenia Almeida; Limeira-de-Oliveira, Francisco

    2012-01-01

    Abstract Protosilvius gurupi sp. n. (Tabanidae, Pangoniinae) is described and illustrated based on seven female and 53 male specimens collected in the Amazonian region at Reserva Biológica Gurupi, Centro Novo do Maranhão municipality, northwest Maranhão, Brazil. This is the first record of Protosilvius in northern Brazil and in the Amazon Basin. An illustrated key to all Protosilvius species is also presented. PMID:23226962

  5. Brazil's premier gold province. Part I: The tectonic, magmatic, and structural setting of the Archean Rio das Velhas greenstone belt, Quadrilátero Ferrífero

    Science.gov (United States)

    Lobato, Lydia; Ribeiro-Rodrigues, Luiz; Zucchetti, Márcia; Noce, Carlos; Baltazar, Orivaldo; da Silva, Luiz; Pinto, Claiton

    2001-07-01

    Rocks of the Rio das Velhas Supergroup comprise one of the most significant Archean greenstone-belt successions in Brazil, in both their appreciable mineral productivity and extensive mineral potential. A large part of this greenstone belt is contained within the Quadrilátero Ferrífero (Iron Quadrangle) region, Minas Gerais state, southeastern Brazil, which occupies the southernmost portion of the São Francisco craton. The Nova Lima Group rocks, at the base of the Rio das Velhas greenstone belt, host important orogenic gold deposits. The group contains lithological associations from bottom to top as follows: (1) mafic-ultramafic volcanic, (2) volcanic-chemical, (3) clastic-chemical, (4) volcaniclastic, and (5) resedimented rocks. Rocks of the resedimented, volcanic-chemical, and mafic-ultramafic volcanic associations mainly host the most important gold deposits. An early compressional deformation occurs in the rocks of the Rio das Velhas greenstone belt and basement gneisses, with tangential thrusting from the north to the south or southwest. Structures generated during a second, compressional deformation, encompass NW-striking thrust faults and SW-vergent, tight to isoclinal folds, inferring a general southwest transport direction. In the central portion of the Quadrilátero Ferrífero, the Paciência lineament, which strikes northwest and dips to the northeast in the south, or strikes northeast and dips to the southeast in the north, is a thrust-related, oblique ramp fault that hosts important gold deposits. The convergence of these two trends in the Nova Lima region is accommodated by roughly E-W-striking transcurrent faults, which are the most favored sites for large gold concentrations. Intracratonic extension in Late Archean to early Paleoproterozoic times and NW-vergent, Trans-Amazonian compressional deformation post-date gold deposition. Late extension during the Paleoproterozoic led to basin formation and the prominent dome-and-keel architecture of the

  6. Persistent effects of pre-Columbian plant domestication on Amazonian forest composition

    NARCIS (Netherlands)

    Levis, C.; Costa, Flávia R.C.; Bongers, F.; Pena Claros, M.; Braga Junqueira, A.

    2017-01-01

    The extent to which pre-Columbian societies altered Amazonian landscapes is hotly debated. We performed a basin-wide analysis of pre-Columbian impacts on Amazonian forests by overlaying known archaeological sites in Amazonia with the distributions and abundances of 85 woody species domesticated by p

  7. Persistent effects of pre-Columbian plant domestication on Amazonian forest composition

    NARCIS (Netherlands)

    Levis, C.; Costa, Flávia R.C.; Bongers, F.; Pena Claros, M.; Braga Junqueira, A.

    2017-01-01

    The extent to which pre-Columbian societies altered Amazonian landscapes is hotly debated. We performed a basin-wide analysis of pre-Columbian impacts on Amazonian forests by overlaying known archaeological sites in Amazonia with the distributions and abundances of 85 woody species domesticated by p

  8. Estimating the global conservation status of more than 15,000 Amazonian tree species

    DEFF Research Database (Denmark)

    ter Steege, Hans; Pitman, Nigel C. A.; Killeen, Timothy J.

    2015-01-01

    Estimates of extinction risk for Amazonian plant and animal species are rare and not often incorporated into land-use policy and conservation planning. We overlay spatial distribution models with historical and projected deforestation to show that at least 36% and up to 57% of all Amazonian tree ...

  9. Molecular organization and chromosomal localization of 5S rDNA in Amazonian Engystomops (Anura, Leiuperidae).

    Science.gov (United States)

    Rodrigues, Débora Silva; Rivera, Miryan; Lourenço, Luciana Bolsoni

    2012-03-20

    For anurans, knowledge of 5S rDNA is scarce. For Engystomops species, chromosomal homeologies are difficult to recognize due to the high level of inter- and intraspecific cytogenetic variation. In an attempt to better compare the karyotypes of the Amazonian species Engystomops freibergi and Engystomops petersi, and to extend the knowledge of 5S rDNA organization in anurans, the 5S rDNA sequences of Amazonian Engystomops species were isolated, characterized, and mapped. Two types of 5S rDNA, which were readily differentiated by their NTS (non-transcribed spacer) sizes and compositions, were isolated from specimens of E. freibergi from Brazil and E. petersi from two Ecuadorian localities (Puyo and Yasuní). In the E. freibergi karyotypes, the entire type I 5S rDNA repeating unit hybridized to the pericentromeric region of 3p, whereas the entire type II 5S rDNA repeating unit mapped to the distal region of 6q, suggesting a differential localization of these sequences. The type I NTS probe clearly detected the 3p pericentromeric region in the karyotypes of E. freibergi and E. petersi from Puyo and the 5p pericentromeric region in the karyotype of E. petersi from Yasuní, but no distal or interstitial signals were observed. Interestingly, this probe also detected many centromeric regions in the three karyotypes, suggesting the presence of a satellite DNA family derived from 5S rDNA. The type II NTS probe detected only distal 6q regions in the three karyotypes, corroborating the differential distribution of the two types of 5S rDNA. Because the 5S rDNA types found in Engystomops are related to those of Physalaemus with respect to their nucleotide sequences and chromosomal locations, their origin likely preceded the evolutionary divergence of these genera. In addition, our data indicated homeology between Chromosome 5 in E. petersi from Yasuní and Chromosomes 3 in E. freibergi and E. petersi from Puyo. In addition, the chromosomal location of the type II 5S r

  10. Rapid Amazonian Moisture Oscillations Correlated with Dansgaard-Oeschger Cycles

    Science.gov (United States)

    Wang, X.; Auler, A. S.; Edwards, R.; Cheng, H.; Ito, E.; Dorale, J. A.

    2007-12-01

    Terrestrial paleoclimate records on abrupt climate events from the tropics, e.g. Dansgaard-Oeschger (D-O) oscillations, are still rare, in particular, from Amazonia, which contains the largest tropical rainforest in the world. We have obtained a high-resolution oxygen isotopic record of cave calcite from Caverna Paraíso (PAR, 04o04'S, 55o27'W), Amazonia, Brazil. The chronology was determined by 69 U-Th ages from 4 stalagmites. Tests for equilibrium conditions show that their oxygen isotopic variations are primarily caused by climate change. We thus interpret the Paraíso record, spanning the last 50 thousand years, in terms of meteoric precipitation changes at this equatorial location. The oxygen isotopic profile shows significant abrupt millennial-scale variations during Marine Isotope Stage (MIS) 3, with amplitudes as large as 2 per mil. Using independent age scales, we compare the record to contemporaneous records from caves in eastern China and high-latitude ice cores. During MIS 3, the PAR calcite oxygen isotopic profile correlates remarkably with the Hulu Cave record (Wang Y.J. et al., 2001, Science), indicating that precipitation histories at the two sites are asynchronous, similar to our previous observations from northeastern and southern Brazil speleothems (Wang X.F. et al., 2004, Nature; Wang X.F. et al., 2006, Quat. Sci. Rev.). During MIS 3, Paraíso precipitation also broadly anti-correlates with Greenland D-O events (NGRIP members, 2004, Nature) and positively correlates with Antarctic warm events (EPICA community members, 2006, Nature). Our record adds further support to the idea that abrupt climate events have a worldwide distribution during MIS 3 (Voelker et al., 2002, Quat. Sci. Rev.). The observed correlations between the records support an oceanic meridional overturning circulation mechanism for driving the abrupt millennial-scale events of the last glacial period, coupled with strong air-sea feedbacks from the tropics. In combination with

  11. EASTERN UGANDA

    African Journals Online (AJOL)

    EVALUATION OF SELECTED ELITE POTATO GENOTYPES IN. EASTERN ... Significant

  12. Biogeochemical cycling of urea in the aquatic systems of Pindaré and Turiaçu River basins, a pre-Amazonian floodplain, Baixada Maranhense, Brazil Ciclo biogeoquímico da ureia nos sistemas aquáticos das bacias hidrográficas do Pindaré e Turiaçu, várzea pré-Amazônica, Baixada Maranhense, Brasil

    Directory of Open Access Journals (Sweden)

    Osamu Mitamura

    2012-06-01

    Full Text Available AIM: This work is aimed at extending the understanding of urea cycle in freshwater ecosystems. Its degradation rate concerning microorganisms activities was measured in the turbid waters of Pindaré and Turiaçu rivers located on the pre-Amazonian floodplain, Brazil; METHODS: The Pindaré and Turiaçu aquatic systems have distinct dry and rainy periods. The investigation was developed in the middle of the rainy period, and field activities were carried out in the extensive water bodies from the middle to lower reaches. The rate of degradation in the surface waters of the two aquatic systems was determined with in situ simulation technique using 14C-labelled urea. Photosynthetic rates were determined by the radiocarbon technique simultaneously with experimental measurements of urea degradation rate; RESULTS: Urea degradation rates (sum of carbon incorporation into particulate matter and CO2 liberation into water were 2.0 mg urea C m-3 day-1 in the Pindaré and 17.1 mg urea C m-3 day-1 in the Turiaçu waters. Daylight values were obviously higher than those in the dark, and the urea degradation rates in Turiaçu showed much higher values than those in Pindaré. Most of the urea degradation occurred during the CO2 liberation phase. The average of chlorophyll a specific urea degradation rate was 0.13 and 0.83 mg urea C mg chl.a-1 day-1 in both river waters. The ratio of urea carbon degradation to photosynthetic carbon assimilation in both waters averaged 1.2 and 4.2%, respectively. The residence time of urea in the surface water was calculated as 2.3 to 4.5 days in the Pindaré and 0.21 to 0.50 days in the Turiaçu. Much shorter residence times were obtained in the Turiaçu due to the high degradation rate of urea; CONCLUSION: The correlation coefficient between the urea degradation rate and chlorophyll a or photosynthetic rate showed a statistically significant value in the Turiaçu. This indicates that in the Turiaçu system the urea degradation

  13. Chronology of Terra Firme formation in western Amazonia and implications for the diversification of Amazonian biota

    Science.gov (United States)

    Pupim, Fabiano do N.; Sawakushi, André O.; Hartmann, Gelvam A.; Savian, Jairo F.; Kern, Andrea K.; Mineli, Thays D.; Cruz, Francisco W.; Almeida, Renato P.; Grohmann, Carlos H.; Ribas, Camila C.; d'Horta, Fernando M.; Bertassoli, Dailson J.; Marconato, André; Nogueira, Luciana; Lohmann, Lúcia G.

    2017-04-01

    The shift from a large wetland dominated by avulsive channels and flooded forests to the incised transcontinental Amazon River valley (Várzea) bounded by non-flooded forests (Terra Firme) is suggested as one of the main drivers of diversification of the mega diverse Amazonian Biota. Nonetheless, there is no consensus about the timing of this landscape shift, with the current literature suggesting a period that ranges from the Miocene (11 Ma) and the Late Pleistocene (100 ka). This uncertainty may be due to a lack of absolute ages for the sediments forming Terra Firme forest substrates in western Amazonian lowlands. In Brazil, the Içá Formation represents the uppermost fluvial deposits of Terra Firme forests substrates in western Amazonia. Therefore, a reliable chronology for the last depositional stage of the Içá Formation is key for an improved understanding of the formation of the current Terra Firme-Várzea system. Four sediment profiles were sampled along the margins of the Solimões and Içá rivers for Optically Stimulated Luminescence (OSL) dating, geomagnetic excursions, and palynological analysis. OSL dating was performed in twelve samples using a Single Aliquot Regeneration (SAR) protocol in quartz sand grains. The equivalent doses ranged from 47 to 130 Gy (Central Age Model) and the dose rate values ranged from 0.4 to 2.0 Gy/ka. The resulting sediment burial ages range from 48 to 112 ka. Paleomagnetic data were obtained from samples collected at same profiles sampled for OSL dating and results suggest the presence of Post-Blake geomagnetic excursion ( 100 ka). The age of 100 ka for Post-Blake excursion are adopted for the Geomagnetic Instability Time Scale. Pollen assemblage data show a similarity to a more modern flora and the presence of Alnus clearly points towards Pleistocene deposition as it is unknown before in South America. The combined OSL, paleomagnetism and pollen data is a robust geochronological dataset that indicates Late Pleistocene

  14. Scientific ballooning in Brazil

    Science.gov (United States)

    Corrêa, R.; Rinke, E.; Fernandes, J. O.; Villela, T.

    We present an overview of the scientific ballooning activities that took place in Brazil over the past 30 years as well as the current ongoing efforts in the area. We also briefly describe the balloon launching facility that exists at the Instituto Nacional de Pesquisas Espaciais (National Institute for Space Research) — INPE. Up to now, over 100 scientific balloon experiments, related to Astrophysics, Aeronomy, and Geophysics were launched from Brazil taking advantage of the country's continental dimensions, a well-defined rain season, and a low population density, which offer excellent conditions for scientific ballooning activities. Balloons with volumes up to 500,000 cubic meters can be launched from INPE's balloon launching base (latitude S 22° 4' 2″; longitude W 044° 58' 41″). The availability of good roads and several inland airports in Brazil provides the necessary structure for safe payload retrieval and its rapid return to the balloon base. There are several airports throughout Brazil that can also be used as balloon launching bases, mainly in the country's Eastern region. Overflights of more than 1,000 kilometers are possible and easily attained. Balloon flights ranging from a few hours to long duration flights can be safely verified. The constant climate monitoring through the use of weather satellites information received at INPE provides the necessary data to determine the necessary conditions for a long duration flight. INPE's Center for Weather Forecast and Climate Studies (CPTEC) provides the necessary weather forecast support for launch and payload retrieval.

  15. Influence of hydrological pulse on bacterial growth and DOC uptake in a clear-water Amazonian lake.

    Science.gov (United States)

    Farjalla, Vinicius F; Azevedo, Debora A; Esteves, Francisco A; Bozelli, Reinaldo L; Roland, Fabio; Enrich-Prast, Alex

    2006-08-01

    This study was conducted to evaluate: (1) the bacterial growth and the dissolved organic carbon (DOC) uptake in an Amazonian lake (Lake Batata) at high-water and low-water periods of the flood pulse; (2) the influence of nitrogen and phosphorus (NP) additions on bacterial growth and DOC uptake in Lake Batata at two flood pulse periods; and (3) the bioavailability of the main DOC sources in Lake Batata. Lake Batata is a typical clear-water Amazonian lake, located in the watershed of Trombetas River, Central Amazon, Brazil. Bacterial batch cultures were set up with 90% 0.2-microm filtered water and 10% inoculum from Lake Batata. N-NH(4)NO(3) and P-KH(2)PO(4), with final concentrations of 50 and 5 microM, respectively, were added to the cultures, except for controls. Extra sources of DOC (e.g., algal lysate, plant leachates) were added to constitute six distinct treatments. Bacterial response was measured by maximum bacterial abundance and rates of bacterial production, respiration, DOC uptake, and bacterial growth efficiency (BGE). Bacterial growth and DOC uptake were higher in NP treatments than in controls, indicating a consistent nutrient limitation in Lake Batata. The composition of DOC also seems to be an important regulating factor of bacterial growth in Lake Batata. Seasonally, bacterial growth and DOC bioavailability were higher at low-water period, when the phytoplankton is a significant extra source of DOC, than at high-water period, when the forest is the main source of DOC. DOC bioavailability was better estimated based on the diversity and the diagenetic stage of carbon compounds than on single classes of labile compounds. Changes in BGE were better related to CNP stoichiometry in the water, and the "excess" of organic substrates was oxidized in catabolism, despite the quality of these compounds for bacterial growth. Finally, we conclude that bacterial growth and DOC uptake vary throughout the flood pulse in clear-water Amazonian ecosystems as a result

  16. Prevalence and spatial distribution of intestinal parasitic infections in a rural Amazonian settlement, Acre State, Brazil Prevalência e distribuição espacial de parasitoses intestinais em assentamento agrícola na Amazônia rural, Acre, Brasil

    Directory of Open Access Journals (Sweden)

    Estéfano Alves de Souza

    2007-02-01

    Full Text Available A population-based survey of the prevalence and spatial distribution of intestinal parasitism was carried out in an agricultural settlement in the Amazon Basin of Brazil (Granada, Acre State. More than half (53.4% of the 429 stool specimens from subjects in all age groups, living in 113 households, had cysts, ova, or larvae of intestinal parasites. The most prevalent parasites were Giardia duodenalis (19.6% and soil-transmitted helminths (12.7%; 105 (24.5% subjects were infected with more than one species of parasite. Significant age-related differences in prevalence were only found for G. duodenalis (children 30 years were less affected. Six households (5.3%, situated within a radius of 690m, comprised 48.1% of all subjects harboring soil-transmitted helminths in our study area. Households within this cluster were poorer and more crowded than those outside the cluster. The observed spatial clustering of infections with soil-transmitted helminths provides valuable information for the spatial targeting of sanitary interventions in this area.Estudo de base populacional sobre a prevalência e distribuição de parasitoses intestinais foi realizado em assentamento agrícola na Amazônia Brasileira (Granada, Acre. Mais da metade (53,4% das 429 amostras analisadas de indivíduos de todas as idades, moradores de 113 domicílios, continha cistos, ovos ou larvas de parasitas intestinais. Os parasitas intestinais de maior prevalência foram Giardia duodenalis (19,6% e os geo-helmintos (12,7%; 105 (24,5% indivíduos apresentavam co-infecção por mais de uma espécie de parasita. Houve diferença significativa em relação à idade na prevalência somente de G. duodenalis (crianças 30 anos foram menos afetados. Seis domicílios (5,3%, localizados num raio de 690m, concentraram 48,1% de todos os indivíduos infectados por geo-helmintos na área de estudo. Domicílios incluídos nesse agregado (cluster eram mais pobres e com maior número de habitantes do

  17. Diversity and aspects of the ecology of social wasps (Vespidae, Polistinae in Central Amazonian "terra firme" forest

    Directory of Open Access Journals (Sweden)

    Alexandre Somavilla

    2014-12-01

    Full Text Available Diversity and aspects of the ecology of social wasps (Vespidae, Polistinae in Central Amazonian "terra firme" forest. The knowledge of social wasp richness and biology in the Amazonian region is considered insufficient. Although the Amazonas state is the largest in the region, until now only two brief surveys were conducted there. Considering that the systematic inventory of an area is the first step towards its conservation and wise use, this study presents faunal data on social wasp diversity in a 25 km² area of "terra firme" (upland forest at the Ducke Reserve, Manaus, Amazonas, Brazil. Wasps were collected in the understory, following a protocol of three collectors walking along 60 trails 1,000 m in extension for 16 days between August and October 2010. Methods used were active search of individuals with entomological nets and nest collecting. Fifty-eight species of social wasps, allocated in 13 genera, were recorded; 67% of the collected species belong to Polybia, Agelaia and Mischocyttarus; other genera were represented by only four species or less. The most frequent species in active searches were Agelaia fulvofasciata (DeGeer, 1773, Agelaia testacea (Fabricius, 1804 and Angiopolybia pallens (Lepeletier, 1836. Twelve species were collected in nests. Prior to this study, 65 Polistinae species were deposited at the INPA Collection. Collecting in the study grid, an area not previously sampled for wasps, resulted in an increase of 25% species, and species richness was 86. According to the results, there is evidence that the diversity of social wasps at the Ducke Reserve is even higher, making it one of the richest areas in the Brazilian Amazonia.

  18. Fire-free land use in pre-1492 Amazonian savannas.

    Science.gov (United States)

    Iriarte, José; Power, Mitchell J; Rostain, Stéphen; Mayle, Francis E; Jones, Huw; Watling, Jennifer; Whitney, Bronwen S; McKey, Doyle B

    2012-04-24

    The nature and scale of pre-Columbian land use and the consequences of the 1492 "Columbian Encounter" (CE) on Amazonia are among the more debated topics in New World archaeology and paleoecology. However, pre-Columbian human impact in Amazonian savannas remains poorly understood. Most paleoecological studies have been conducted in neotropical forest contexts. Of studies done in Amazonian savannas, none has the temporal resolution needed to detect changes induced by either climate or humans before and after A.D. 1492, and only a few closely integrate paleoecological and archaeological data. We report a high-resolution 2,150-y paleoecological record from a French Guianan coastal savanna that forces reconsideration of how pre-Columbian savanna peoples practiced raised-field agriculture and how the CE impacted these societies and environments. Our combined pollen, phytolith, and charcoal analyses reveal unexpectedly low levels of biomass burning associated with pre-A.D. 1492 savanna raised-field agriculture and a sharp increase in fires following the arrival of Europeans. We show that pre-Columbian raised-field farmers limited burning to improve agricultural production, contrasting with extensive use of fire in pre-Columbian tropical forest and Central American savanna environments, as well as in present-day savannas. The charcoal record indicates that extensive fires in the seasonally flooded savannas of French Guiana are a post-Columbian phenomenon, postdating the collapse of indigenous populations. The discovery that pre-Columbian farmers practiced fire-free savanna management calls into question the widely held assumption that pre-Columbian Amazonian farmers pervasively used fire to manage and alter ecosystems and offers fresh perspectives on an emerging alternative approach to savanna land use and conservation that can help reduce carbon emissions.

  19. Environmental change and the carbon balance of Amazonian forests.

    Science.gov (United States)

    Aragão, Luiz E O C; Poulter, Benjamin; Barlow, Jos B; Anderson, Liana O; Malhi, Yadvinder; Saatchi, Sassan; Phillips, Oliver L; Gloor, Emanuel

    2014-11-01

    Extreme climatic events and land-use change are known to influence strongly the current carbon cycle of Amazonia, and have the potential to cause significant global climate impacts. This review intends to evaluate the effects of both climate and anthropogenic perturbations on the carbon balance of the Brazilian Amazon and to understand how they interact with each other. By analysing the outputs of the Intergovernmental Panel for Climate Change (IPCC) Assessment Report 4 (AR4) model ensemble, we demonstrate that Amazonian temperatures and water stress are both likely to increase over the 21st Century. Curbing deforestation in the Brazilian Amazon by 62% in 2010 relative to the 1990s mean decreased the Brazilian Amazon's deforestation contribution to global land use carbon emissions from 17% in the 1990s and early 2000s to 9% by 2010. Carbon sources in Amazonia are likely to be dominated by climatic impacts allied with forest fires (48.3% relative contribution) during extreme droughts. The current net carbon sink (net biome productivity, NBP) of +0.16 (ranging from +0.11 to +0.21) Pg C year(-1) in the Brazilian Amazon, equivalent to 13.3% of global carbon emissions from land-use change for 2008, can be negated or reversed during drought years [NBP = -0.06 (-0.31 to +0.01) Pg C year(-1) ]. Therefore, reducing forest fires, in addition to reducing deforestation, would be an important measure for minimizing future emissions. Conversely, doubling the current area of secondary forests and avoiding additional removal of primary forests would help the Amazonian gross forest sink to offset approximately 42% of global land-use change emissions. We conclude that a few strategic environmental policy measures are likely to strengthen the Amazonian net carbon sink with global implications. Moreover, these actions could increase the resilience of the net carbon sink to future increases in drought frequency. © 2014 The Authors. Biological Reviews © 2014 Cambridge Philosophical

  20. Large-scale degradation of Amazonian freshwater ecosystems

    Science.gov (United States)

    Castello, L.; Macedo, M.

    2016-12-01

    The integrity of freshwater ecosystems depends on their hydrological connectivity with land, water, and climate systems. Hydrological connectivity regulates the structure and function of Amazonian freshwater ecosystems and the provisioning of services that sustain local populations. However, the hydrological connectivity of Amazonian freshwater ecosystems is increasingly disrupted by construction of dams, mining, land-cover changes, and global climate change. This review analyzes these drivers of degradation; evaluates their impacts on hydrological connectivity; and identifies policy deficiencies that hinder freshwater ecosystem protection. There are 155 large hydroelectric dams in operation, 21 dams under construction, and there will be only three free-flowing tributaries if all 277 planned dams for the Basin are built. Land-cover changes driven by mining, dam and road construction, and agriculture and cattle ranching have already affected 20% of the Basin and up to 50% of riparian forests in some regions. Global climate change will likely exacerbate these impacts by creating warmer and dryer conditions, with less predictable rainfall and more extreme events (e.g. droughts and floods). The resulting hydrological alterations are rapidly degrading freshwater ecosystems both independently and via complex feedbacks and synergistic interactions. The ecosystem impacts include biodiversity loss, warmer stream temperatures, stronger and more frequent floodplain fires, and changes to biogeochemical cycles, transport of organic and inorganic materials, and freshwater community structure and function. The impacts also include reductions in water quality, fish yields, and availability of water for navigation, power generation, and human use. This degradation of Amazonian freshwater ecosystems cannot be curbed presently because existing policies are inconsistent across the Basin, ignore cumulative effects, and do not consider the hydrological connectivity of freshwater

  1. Alluvial plain dynamics in the southern Amazonian foreland basin

    Science.gov (United States)

    Lombardo, Umberto

    2016-05-01

    Alluvial plains are formed with sediments that rivers deposit on the adjacent flood-basin, mainly through crevasse splays and avulsions. These result from a combination of processes, some of which push the river towards the crevasse threshold, while others act as triggers. Based on the floodplain sedimentation patterns of large rivers in the southern Amazonian foreland basin, it has been suggested that alluvial plain sediment accumulation is primarily the result of river crevasse splays and sheet sands triggered by above-normal precipitation events due to La Niña. However, more than 90 % of the Amazonian river network is made of small rivers and it is unknown whether small river floodplain sedimentation is influenced by the ENSO cycle as well. Using Landsat images from 1984 to 2014, here I analyse the behaviour of all 12 tributaries of the Río Mamoré with a catchment in the Andes. I show that these are very active rivers and that the frequency of crevasses is not linked to ENSO activity. The data suggest that most of the sediments eroded from the Andes by the tributaries of the Mamoré are deposited in the alluvial plains, before reaching the parent river. The mid-to-late Holocene paleo-channels of these rivers are located tens of kilometres further away from the Andes than the modern crevasses. I conclude that the frequency of crevasses is controlled by intrabasinal processes that act on a yearly to decadal timescale, while the average location of the crevasses is controlled by climatic or neo-tectonic events that act on a millennial scale. Finally, I discuss the implications of river dynamics on rural livelihoods and biodiversity in the Llanos de Moxos, a seasonally flooded savannah covering most of the southern Amazonian foreland basin and the world's largest RAMSAR site.

  2. Late Miocene Tidal Deposits in the Amazonian Foreland Basin

    Science.gov (United States)

    Rasanen, Matti E.; Linna, Ari M.; Santos, Jose C. R.; Negri, Francisco R.

    1995-07-01

    Late Miocene tidal sediments of Acre, Brazilian Amazonia, were deposited in an embayment or interior seaway located in the sub-Andean zone. This late Tertiary embayment system may once have connected the Caribbean with the South Atlantic. The tidal coasts of the embayment-seaway have provided an avenue for the earliest waif (over water) dispersal phases of the great American biotic interchange in the late Miocene. The subsequent change from semimarine to terrestrial environments is of value in assessing the importance of earlier hypotheses on the evolution of the western Amazonian landscape and gives insight into the formation of several observed biogeographic patterns, especially of aquatic biota.

  3. Studies on the pharmacological activity of Amazonian Euphorbiaceae.

    Science.gov (United States)

    Macrae, W D; Hudson, J B; Towers, G H

    1988-01-01

    Plant material from 34 Amazonian species of the family Euphorbiaceae were collected and extracts prepared. Sixteen of these species have a documented use as a medicinal agent. The extracts were tested for their ability to inhibit the growth of the bacteria, Escherichia coli and Staphylococcus aureus; the yeasts, Saccharomyces cerevisiae and Candida albicans; the dermatophytic fungi, Microsporum canis, Microsporum fulvum, Microsporum gypseum and Trichophyton gallinae; the viruses, Sindbis virus and murine cytomegalovirus; and tumours induced on potato discs by Agrobacterium tumefaciens. They were also examined for their toxicity to brine shrimp, Artemia salina. The results are discussed with respect to ethnobotanical information available for some of the species.

  4. Medicinal plants of the Achuar (Jivaro) of Amazonian Ecuador: ethnobotanical survey and comparison with other Amazonian pharmacopoeias.

    Science.gov (United States)

    Giovannini, Peter

    2015-04-22

    This paper presents the first ethnobotanical survey conducted among the Achuar (Jivaro), indigenous people living in Amazonian Ecuador and Peru. The aims of this study are: (a) to present and discuss Achuar medicinal plant knowledge in the context of the epidemiology of this population (b) to compare the use of Achuar medicinal plants with the uses reported among the Shuar Jivaro and other Amazonian peoples. The author conducted field research in 9 indigenous villages in the region of Morona Santiago and Pastaza in Ecuador. Semi-structured interviews on local illnesses and herbal remedies were carried out with 82 informants and plant specimens were collected and later identified in Quito. A literature research was conducted on the medicinal species reported by Achuar people during this study. The most reported medicinal plants are species used by the Achuar to treat diarrhoea, parasites infection, fractures, wounds, and snakebites. Informants reported the use of 134 medicinal species for a total of 733 recorded use-reports. Of these 134 species, 44 are reported at least 3 times for one or more specific disease condition for a total of 56 uses. These species are considered a core kit of medicinal plants of the Achuar of Ecuador. Most of these medicinal species are widely used in the Amazon rainforest and in many other parts of Latin America. The author documented a core kit of 44 medicinal plants used among the Achuar of Ecuador and found that this core set of medicinal plants reflects local epidemiological concerns and the pharmacopoeias of the Shuar and other Amazonian groups. These findings suggest that inter-group diffusion of medicinal plant knowledge had a prominent role in the acquisition of current Achuar knowledge of medicinal plants. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  5. Amazonian indigenous settlement and local development in Pastaza, Ecuador

    Directory of Open Access Journals (Sweden)

    Ruth I. Arias-Gutiérrez

    2016-07-01

    Full Text Available In six Amazonian indigenous communities that call to their selves as membership of nación Kichwa, located in Pastaza province, in Ecuador, it is analyzed the process of inhabitation, population characteristics, how much the territory is enough for food requirements for the indigenous families, and their use of land, to determine important factors to improve strategies for local sustainable development. It is considered important because Ecuador has constitutional protection for plural ethnicity and it is looking for improving a new productivity matrix that let down extraction and contamination and raise another matrix based on knowledge and richness from natural renewable resources. Survey used statistics information, qualitative analysis around reality in process, participant research, documentary analysis, oral history and surveys to leadership and family`s chiefs. Results confirm that communities hold standing their identity and knowledge systems of the Amazonian environment, whose conservation they need. Those are factors to be included in local development strategies that let people become safe from effects of extractives activities that are dangerous for culture and environment, in the geographic and biological diversity of the high Ecuadorian Amazonia.

  6. HLA genes in Lamas Peruvian-Amazonian Amerindians.

    Science.gov (United States)

    Moscoso, Juan; Seclen, Segundo; Serrano-Vela, Juan I; Villena, A; Martinez-Laso, Jorge; Zamora, Jorge; Moreno, Almudena; Ira-Cachafeiro, Juan; Arnaiz-Villena, Antonio

    2006-04-01

    The Lamas Amerindians are the Chancas descents who established before 1532 a.d. (Spanish conquest) at Lamas City, Wayku quarter in a Peruvian-Amazonian province (San Martin). The Lamas HLA profile shows significant differences with other Amerindians HLA profile, i.e.: (a) a higher number of newly found haplotypes compared to other studied Amerindian populations, particularly HLA-A*02-B*48-DRB1*0403-DQB1*0302, A*02-B*48-DRB1*0804-DQB1*0402 and A*02-B*40-DRB1*0407-DQB1*0302; (b) a relative high frequency of HLA-DRB1*0901 (a high frequency southern Asian allele) and HLA-B*48 (a Na-Dene, Siberian and Eskimo allele); both alleles are also found frequently in Quechuas and Aymaras, but not in many other (particularly Meso American) Amerindians and (c) correspondence and neighbor-joining dendrogram analyses show that Lamas (Chancas) may have an origin close to Amazonian Indians that later reached the Andean altiplano.

  7. A free-access online key to identify Amazonian ferns

    Directory of Open Access Journals (Sweden)

    Gabriela Zuquim

    2017-03-01

    Full Text Available There is urgent need for more data on species distributions in order to improve conservation planning. A crucial but challenging aspect of producing high-quality data is the correct identification of organisms. Traditional printed floras and dichotomous keys are difficult to use for someone not familiar with the technical jargon. In poorly known areas, such as Amazonia, they also become quickly outdated as new species are described or ranges extended. Recently, online tools have allowed developing dynamic, interactive, and accessible keys that make species identification possible for a broader public. In order to facilitate identifying plants collected in field inventories, we developed an internet-based free-access tool to identify Amazonian fern species. We focused on ferns, because they are easy to collect and their edaphic affinities are relatively well known, so they can be used as an indicator group for habitat mapping. Our key includes 302 terrestrial and aquatic entities mainly from lowland Amazonian forests. It is a free-access key, so the user can freely choose which morphological features to use and in which order to assess them. All taxa are richly illustrated, so specimens can be identified by a combination of character choices, visual comparison, and written descriptions. The identification tool was developed in Lucid 3.5 software and it is available at http://keyserver.lucidcentral.org:8080/sandbox/keys.jsp.

  8. Amazonian Buriti oil: chemical characterization and antioxidant potential

    Energy Technology Data Exchange (ETDEWEB)

    Speranza, P.; Oliveira Falcao, A. de; Alves Macedo, J.; Silva, L.H.M. da; Rodrigues, A.M. da C.; Alves Macedo, G.

    2016-07-01

    Buriti oil is an example of an Amazonian palm oil of economic importance. The local population uses this oil for the prevention and treatment of different diseases; however, there are few studies in the literature that evaluate its properties. In this study, detailed chemical and antioxidant properties of Buriti oil were determined. The predominant fatty acid was oleic acid (65.6%) and the main triacylglycerol classes were tri-unsaturated (50.0%) and di-unsaturated-mono-saturated(39.3%) triacylglycerols. The positional distribution of the classes of fatty acids on the triacylglycerol backbone indicated a saturated and unsaturated fatty acid relationship similar in the three-triacylglycerol positions. All tocopherol isomers were present, with a total content of 2364.1 mg·kg−1. α-tocopherol constitutes 48% of the total tocopherol content, followed by γ- tocopherol (45%). Total phenolic (107.0 mg gallic acid equivalent·g−1 oil) and β-carotene (781.6 mg·kg−1) were particularly high in this oil. The highest antioxidant activity against the free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) was obtained at an oil concentration of 50 mg·mL−1 (73.15%). The antioxidant activity evaluated by the Oxygen Radical Absorbance Capacity (ORAC) was 95.3 μmol Trolox equivalent·g−1 oil. These results serve to present Buriti oil as an Amazonian resource for cosmetic, food and pharmaceuticals purposes. (Author)

  9. Spatial trends in leaf size of Amazonian rainforest trees

    Directory of Open Access Journals (Sweden)

    A. C. M. Malhado

    2009-02-01

    Full Text Available Leaf size influences many aspects of tree function such as rates of transpiration and photosynthesis and, consequently, often varies in a predictable way in response to environmental gradients. The recent development of pan-Amazonian databases based on permanent botanical plots (e.g. RAINFOR, ATDN has now made it possible to assess trends in leaf size across environmental gradients in Amazonia. Previous plot-based studies have shown that the community structure of Amazonian trees breaks down into at least two major ecological gradients corresponding with variations in soil fertility (decreasing south to northeast and length of the dry season (increasing from northwest to south and east. Here we describe the results of the geographic distribution of leaf size categories based on 121 plots distributed across eight South American countries. We find that, as predicted, the Amazon forest is predominantly populated by tree species and individuals in the mesophyll size class (20.25–182.25 cm2. The geographic distribution of species and individuals with large leaves (>20.25 cm2 is complex but is generally characterized by a higher proportion of such trees in the north-west of the region. Spatially corrected regressions reveal weak correlations between the proportion of large-leaved species and metrics of water availability. We also find a significant negative relationship between leaf size and wood density.

  10. Amazonian and neotropical plant communities on glacial time-scales: The failure of the aridity and refuge hypotheses

    Science.gov (United States)

    Colinvaux, P. A.; De Oliveira, P. E.; Bush, M. B.

    2000-01-01

    Plants respond to Pleistocene climatic change as species, not as associations or biomes. This has been demonstrated unequivocally by paleobotanical data for temperate latitudes. In the far richer vegetations of the tropics species populations also fluctuated independently in response to climatic forcing, from their longlasting glacial states to the patterns of brief interglacials like the present and back again. We use pollen data to reconstruct the vegetation of the Amazon basin in oxygen isotope stages 3 and 2 of the last glaciation in order to measure how the plant populations of the Amazon responded to the global warming at the onset of the Holocene. We find that plant communities of the neotropics vent copious pollen to lake sediments and that this pollen yields powerful signals for community composition. Three continuous sedimentary records reaching through oxygen isotope stage 2 are available from the Amazon lowlands, those from Carajas, Lake Pata and marine deposits off the mouth of the Amazon River. All three records yield pollen histories of remarkable constancy and stability. By comparing them with deposits of equal antiquity from the cerrado (savanna) of central Brazil, we show that most of the Amazon lowlands remained under forest throughout a glacial cycle. This forest was never fragmented by open vegetation as postulated by the refugia hypothesis. Instead the intact forest of glacial times included significant populations of plants that are now montane, suggesting that the global warming of the early Holocene resulted in the expulsion of heat intolerant plants from the lowland forest. Pollen data from the Amazonian flank of the Andes and from Pacific Panama provide evidence that populations of these heat intolerant plants survive the heat of interglacials in part by maintaining large populations at cooler montane altitudes. Our conclusion that the Amazon lowlands were forested in glacial times specifically refutes the hypothesis of Amazonian glacial

  11. Ethnoveterinary knowledge of the inhabitants of Marajó Island, Eastern Amazonia, Brazil Conhecimento etnoveterinário dos habitantes da Ilha de Marajó, Amazônia Oriental, Brasil

    Directory of Open Access Journals (Sweden)

    Maria Vivina Barros Monteiro

    2011-01-01

    Full Text Available There have been ethnoveterinary reports from around the world investigating plant usage in therapeutic protocols; however, there is no information regarding the ethnoveterinary practices in Brazilian Amazonia. The objective of this work was to register and document the ethnoveterinary knowledge of the inhabitants of the Island of Marajó, eastern Amazonia, Brazil. In the study, interviews were conducted with 50 individuals, with the application of semi-structured questionnaires that were quantitatively analyzed using descriptive statistic methods of frequency distribution. Use-value was calculated to determine the most important species. Samples of plants that were reported to have medicinal value were collected and identified by botanical classification. Fifty plants, distributed among 48 genera and 34 families, were indicated for 21 different medicinal uses. The family Asteraceae had the largest number of reported species; Carapa guianensis Aubl., Copaifera martii Hayne, Crescentia cujete L., Caesalpinia ferrea Mart., Chenopodium ambrosioides L., Jatropha curcas L. and Momordica charantia L. were species with highest use- value. The plant parts that were more commonly utilized for the preparation of ethnoveterinary medicines were the leaves (56%, bark (18%, roots (14%, seeds (14% and fruit (8%. With regard to usage, tea was reported as a usage method by 56% of the informants; most preparations (90.9% utilized only a single plant. In addition to medicinal plants, informants reported using products of animal and mineral origin. The present study contributed to the construction of an inventory of Marajó Island's ethnoveterinary plants, which might be the basis for future scientific validation studies.Em várias partes do mundo existem relatos etnoveterinários sobre a utilização de plantas em protocolos terapêuticos, entretanto não existem informações disponíveis sobre a etnoveterinária praticada na Amazônia brasileira. Desta forma

  12. Low plant density enhances gene dispersal in the Amazonian understory herb Heliconia acuminata.

    Science.gov (United States)

    Côrtes, Marina C; Uriarte, María; Lemes, Maristerra R; Gribel, Rogério; Kress, W John; Smouse, Peter E; Bruna, Emilio M

    2013-11-01

    In theory, conservation genetics predicts that forest fragmentation will reduce gene dispersal, but in practice, genetic and ecological processes are also dependent on other population characteristics. We used Bayesian genetic analyses to characterize parentage and propagule dispersal in Heliconia acuminata L. C. Richard (Heliconiaceae), a common Amazonian understory plant that is pollinated and dispersed by birds. We studied these processes in two continuous forest sites and three 1-ha fragments in Brazil's Biological Dynamics of Forest Fragments Project. These sites showed variation in the density of H. acuminata. Ten microsatellite markers were used to genotype flowering adults and seedling recruits and to quantify realized pollen and seed dispersal distances, immigration of propagules from outside populations, and reproductive dominance among parents. We tested whether gene dispersal is more dependent on fragmentation or density of reproductive plants. Low plant densities were associated with elevated immigration rates and greater propagule dispersal distances. Reproductive dominance among inside-plot parents was higher for low-density than for high-density populations. Elevated local flower and fruit availability is probably leading to spatially more proximal bird foraging and propagule dispersal in areas with high density of reproductive plants. Nevertheless, genetic diversity, inbreeding coefficients and fine-scale spatial genetic structure were similar across populations, despite differences in gene dispersal. This result may indicate that the opposing processes of longer dispersal events in low-density populations vs. higher diversity of contributing parents in high-density populations balance the resulting genetic outcomes and prevent genetic erosion in small populations and fragments.

  13. Mercury Bioaccumulation in the Brazilian Amazonian Tucunares (Cichla sp., Cichlidae, Perciformes

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    Maria Josefina Reyna Kurtz

    2008-08-01

    Full Text Available There are emissions of mercury to the atmosphere, soil and rivers of the Brazilian Amazon stem from many sources. Once in the atmosphere, the metal is oxidized and immediately deposited. In the water, the transformation to methylmercury takes place mostly by the action of microorganisms. The formation of methylmercury increases the dispersion and bioavailability of the element in the aquatic environment. Methylmercury can be assimilated by plankton and enters the food chain. The concentration of mercury increases further up in the trophic levels of the chain and reaches the highest values in carnivorous fishes like tucunare. Therefore, mercury emissions cause the contamination of natural resources and increase risks to the health of regular fish consumers. The objective of this work was to study the bioaccumulation of mercury in tucunares (Cichla sp., top predators of the food chain. The fishes were collected at two locations representative of the Amazonian fluvial ecosystem, in the state of Pará, Brazil, in 1992 and 2001. One location is near a former informal gold mining area. The other is far from the mining area and is considered pristine. Average values of total mercury concentration and accumulation rates for four different collection groups were compared and discussed. Tucunares collected in 2001 presented higher mercury contents and accumulated mercury faster than tucunares collected in 1992 notwithstanding the decline of mining activities in this period. The aggravation of the mercury contamination with time not only in an area where informal gold mining was practiced but also far from this area is confirmed.

  14. The PIATAM MAR I Project and its environmental and social management of the Amazonian coastal zone; O Projeto PIATAM MAR I e a gestao ambiental e social da zona costeira amazonica

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Edson R.S.P. da; Miranda, Fernando P. de [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES). Geoquimica]. E-mails: ercunha@petrobras.com.br; fmiranda@cenpes.petrobras.com.br; Souza Filho, Pedro Walfir Martins [Universidade Federal do Para (UFPA), Belem, PA (Brazil)]. E-mail: walfir@ufpa.br; Sales, Maria E. da C. [Museu Paraense Emilio Goeldi (MPEG), Belem, PA (Brazil)]. E-mail: bia@museu-goeldi.br; Landau, Luiz [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Instituto Alberto Luiz Coimbra de Pos-Graduacao e Pesquisa de Engenharia (COPPE)]. E-mail: landau@lamce.ufrj.br

    2004-07-01

    PETROBRAS is carrying out applied research as an aid to environmental management and systematic monitoring of the complex Amazonian ecosystem. This effort is contemplated in Western Amazonia by projects PIATAM II, PIATAM III, and Cognitus I. PIATAM MAR I was recently extended the scientific benefits of this initiative to the Amazonian coast. Data acquired up to now in this region are stored in different Institutions using distinct structures and formats. Such a circumstance is a hindrance to their application in a multidisciplinary fashion for mapping environmental sensitivity to oil spills along the shoreline therefore, the prime objective of PIATAM MAR I is to consolidate in digital form environmental information available in Eastern Amazonia, in order to allow the integrated geographic analysis of this data set. Such a procedure will make feasible the construction of environmental sensitivity maps tailored to the unique conditions of the Amazonian coast (high tides, huge fluvial discharge, and mangrove development for thousands of kilometers). The research will offer the conceptual basis for systematic monitoring by PETROBRAS in the region, aiming at avoiding environmental damage to nature and society caused by oil spills. (author)

  15. Draft Genome Sequence of Microcystis aeruginosa CACIAM 03, a Cyanobacterium Isolated from an Amazonian Freshwater Environment

    Science.gov (United States)

    Castro, Wendel Oliveira; Lima, Alex Ranieri Jerônimo; Moraes, Pablo Henrique Gonçalves; Siqueira, Andrei Santos; Aguiar, Délia Cristina Figueira; Baraúna, Anna Rafaella Ferreira; Martins, Luisa Carício; Fuzii, Hellen Thais; de Lima, Clayton Pereira Silva; Vianez-Júnior, João Lídio Silva Gonçalves; Nunes, Márcio Roberto Teixeira; Dall'Agnol, Leonardo Teixeira

    2016-01-01

    Given its toxigenic potential, Microcystis aeruginosa is an important bloom-forming cyanobacterium. Here, we present a draft genome and annotation of the strain CACIAM 03, which was isolated from an Amazonian freshwater environment. PMID:27856592

  16. Unihemispheric slow-wave sleep in the Amazonian dolphin, Inia geoffrensis.

    Science.gov (United States)

    Mukhametov, L M

    1987-08-18

    An electroencephalographic study of sleep in Amazonian dolphins, Inia geoffrensis, revealed that unihemispheric slow-wave sleep is the dominant sleep type in this species, as in the other two dolphin species that were studied earlier.

  17. Multiple constraint modeling of nutrient cycling stoichiometry following forest clearing and pasture abandonment in the Eastern Amazon

    Science.gov (United States)

    Davidson, Eric; Nifong, Rachel

    2017-04-01

    While deforestation has declined since its peak, land-use change continues to modify Amazonian landscapes. The responses and feedbacks of biogeochemical cycles to these changes play an important role in determining possible future trajectories of ecosystem function and for land stewardship through effects on rates of secondary forest regrowth, soil emissions of greenhouse gases, inputs of nutrients to groundwater and streamwater, and nutrient management in agroecosystems. Here we present a new synthetic analyses of data from the NASA-supported LBA-ECO project and others datasets on nutrient cycling in cattle pastures, secondary forests, and mature forests at Paragominas, Pará, Brazil. We have developed a stoichiometric model relating C-N-P interactions during original forest clearing, extensive and intensive pasture management, and secondary forest regrowth, constrained by multiple observations of ecosystem stocks and fluxes in each land use. While P is conservatively cycled in all land uses, we demonstrate that pyrolyzation of N during pasture formation and during additional burns for pasture management depletes available-N pools, consistent with observations of lower rates of N leaching and trace gas emission and consistent with secondary forest growth responses to experimental N amendments. The soils store large stocks of N and P, and our parameterization of available forms of these nutrients for steady-state dynamics in the mature forest yield reasonable estimates of net N and P mineralization available for grasses and secondary forest species at rates consistent with observed biomass accumulation and productivity in these modified ecosystems. Because grasses and forests have much different demands for N relative to P, the land use has important biogeochemical impacts. The model demonstrates the need for periodic P inputs for sustainable pasture management and for a period of significant biological N fixation for early-to-mid-successional secondary forest

  18. Integrating regional and continental scale comparisons of tree composition in Amazonian terra firme forests

    Science.gov (United States)

    Honorio Coronado, E. N.; Baker, T. R.; Phillips, O. L.; Pitman, N. C. A.; Pennington, R. T.; Vásquez Martínez, R.; Monteagudo, A.; Mogollón, H.; Dávila Cardozo, N.; Ríos, M.; García-Villacorta, R.; Valderrama, E.; Ahuite, M.; Huamantupa, I.; Neill, D. A.; Laurance, W. F.; Nascimento, H. E. M.; Soares de Almeida, S.; Killeen, T. J.; Arroyo, L.; Núñez, P.; Freitas Alvarado, L.

    2009-01-01

    We contrast regional and continental-scale comparisons of the floristic composition of terra firme forest in South Amazonia, using 55 plots across Amazonia and a subset of 30 plots from northern Peru and Ecuador. Firstly, we examine the floristic patterns using both genus- or species-level data and find that the species-level analysis more clearly distinguishes different plot clusters. Secondly, we compare the patterns and causes of floristic differences at regional and continental scales. At a continental scale, ordination analysis shows that species of Lecythidaceae and Sapotaceae are gradually replaced by species of Arecaceae and Myristicaceae from eastern to western Amazonia. These floristic gradients are correlated with gradients in soil fertility and to dry season length, similar to previous studies. At a regional scale, similar patterns are found within north-western Amazonia, where differences in soil fertility distinguish plots where species of Lecythidaceae, characteristic of poor soils, are gradually replaced by species of Myristicaceae on richer soils. The main coordinate of this regional-scale ordination correlates mainly with concentrations of available calcium and magnesium. Thirdly, we ask at a regional scale within north-western Amazonia, whether soil fertility or other distance dependent processes are more important for determining variation in floristic composition. A Mantel test indicates that both soils and geographical distance have a similar and significant role in determining floristic similarity across this region. Overall, these results suggest that regional-scale variation in floristic composition can rival continental scale differences within Amazonian terra firme forests, and that variation in floristic composition at both scales is dependent on a range of processes that include both habitat specialisation related to edaphic conditions and other distance-dependent processes. To fully account for regional scale variation in continental

  19. Integrating regional and continental scale comparisons of tree composition in Amazonian terra firme forests

    Directory of Open Access Journals (Sweden)

    E. N. Honorio Coronado

    2009-01-01

    Full Text Available We contrast regional and continental-scale comparisons of the floristic composition of terra firme forest in South Amazonia, using 55 plots across Amazonia and a subset of 30 plots from northern Peru and Ecuador. Firstly, we examine the floristic patterns using both genus- or species-level data and find that the species-level analysis more clearly distinguishes different plot clusters. Secondly, we compare the patterns and causes of floristic differences at regional and continental scales. At a continental scale, ordination analysis shows that species of Lecythidaceae and Sapotaceae are gradually replaced by species of Arecaceae and Myristicaceae from eastern to western Amazonia. These floristic gradients are correlated with gradients in soil fertility and to dry season length, similar to previous studies. At a regional scale, similar patterns are found within north-western Amazonia, where differences in soil fertility distinguish plots where species of Lecythidaceae, characteristic of poor soils, are gradually replaced by species of Myristicaceae on richer soils. The main coordinate of this regional-scale ordination correlates mainly with concentrations of available calcium and magnesium. Thirdly, we ask at a regional scale within north-western Amazonia, whether soil fertility or other distance dependent processes are more important for determining variation in floristic composition. A Mantel test indicates that both soils and geographical distance have a similar and significant role in determining floristic similarity across this region. Overall, these results suggest that regional-scale variation in floristic composition can rival continental scale differences within Amazonian terra firme forests, and that variation in floristic composition at both scales is dependent on a range of processes that include both habitat specialisation related to edaphic conditions and other distance-dependent processes. To fully account for regional scale

  20. Mapping phytophysiognomies to undisclosed past landscape in an Amazonian wetland

    Science.gov (United States)

    Cremon, E.; Rossetti, D.; Zani, H.

    2012-12-01

    Wetlands cover 800,000 km2 in the Amazon basin, and these not distributed randomly in the landscape. These areas record a complex geomorphological history during the late Quaternary, mainly due to interplay of tectonics and climatic changes, which resulted in high volumes of sediment deposited in renewed accommodation spaces. It is interesting that these wetlands are highlighted by open vegetation of non-random distribution in contrast with the surrounding rainforest. In general, natural patches of open vegetation within the Amazonian forest have been most often assigned to past arid climatic episodes, or contrasting soil properties. In this work, we analyzed the relationship between geomorphology and the distribution of vegetation patterns over an Amazonian wetland located in the interfluve of the Negro and Branco Rivers. This area is interesting because it contains one of the largest (i.e., more than 100 km in length and 50 km in width) patches of open vegetation (mostly grassland campinarana) in sharp contrast with the rainforest. The main goal was to perform a phytophysiognomic map based on decision tree classifier and data mining of reflectance factor and backscattering using TM/Landsat (dry season) and PALSAR (wet season) images. Five phytophysiognomies were categorized: rainforest; flooded forest; wooded open vegetation; grassy-shrubby open vegetation; and water body. The output map showed an overall accuracy of 94% and Kappa index of 0.93 (p grassy, shrubby and woody) from forested areas (rainforest and flooded forest). Together with the visual interpretation of remote sensing products, the achieved phytophysiognomic map served as the basis for a geomorphological interpretation of the study area. Hence, grassy and shrubby open vegetation class defines a triangular, cone-shaped morphology sharply bounded by flooded and dense forests. Within the open forest, there are also numerous, narrow and elongated belts of wooded open vegetation and forest, which

  1. C dynamics in Amazonian podzols under climate change

    Science.gov (United States)

    Nunan, Naoise; Soro, Andre; Potard, Kevin; Pouteau, Valerie; Montes, Celia; Melphi, Adolpho; Lucas, Yves; Chenu, Claire

    2016-04-01

    It has recently been shown that the C stocks in Amazonian podzols are very large. They are much larger than was previously thought, particularly in the Bh horizon, which has been estimated to contain in excess of 13Pg C for Amazonia alone. It is predicted that the changes in regional climate will result in a drier soil water regime which may affect the C dynamics in these soils that are usually saturated. In order to determine the vulnerability to change of the organic C contained in the Amazonian podzols, a series of incubation experiments were established in which the effects of a number of different factors on microbial decomposition were measured. The direct effect of drier soil water regimes was tested by incubating undisturbed cores from the Bh horizon at a range of matric potentials (saturation to wilting point). Contrary to what is usually found in soils, no significant difference in mineralisation was found among matric potentials, suggesting that other factors control microbial mineralisation of this organic C. The effect of nitrogen additions, of anaerobic conditions and of the addition labile C substrate were also tested on undisturbed cores of the Bh horizon of the podzols. Samples incubated under aerobic conditions produced 3 times more CO2 than samples incubated under anaerobic conditions, whilst samples incubated under aerobic conditions with the addition of N mineralised 6.7 times more CO2 than the anaerobic samples. The addition of labile C did not have a significant effect on C mineralisation, i.e. there was no priming effect. The combined addition of labile C and mineral N did not stimulate C mineralisation more than N additions alone. By extrapolating the differences obtained here to the whole of the Amazonian podzols, it is estimated that changes in conditions which result in an increase in O2 and in N (i.e. changes in vegetation due to increases in dry periods with the establishment of a savanna for example) in the soil will cause the release

  2. Estimating the global conservation status of more than 15,000 Amazonian tree species

    DEFF Research Database (Denmark)

    ter Steege, Hans; Pitman, Nigel C. A.; Killeen, Timothy J.

    2015-01-01

    Estimates of extinction risk for Amazonian plant and animal species are rare and not often incorporated into land-use policy and conservation planning. We overlay spatial distribution models with historical and projected deforestation to show that at least 36% and up to 57% of all Amazonian tree...... degradation, highlighting the key roles that protected areas, indigenous peoples, and improved governance can play in preventing large-scale extinctions in the tropics in this century....

  3. Estimating the global conservation status of more than 15,000 Amazonian tree species

    OpenAIRE

    ter Steege, Hans; Nigel C.A. Pitman; Killeen, Timothy J; Laurance, William F.; Peres, Carlos A.; Guevara, Juan Ernesto; Salomão, Rafael P; Castilho, Carolina V; Amaral, Ieda; de Almeida Matos, Francisca Dionízia; de Souza Coelho, Luiz; Magnusson, William E.; Phillips, Oliver L.; de Andrade Lima Filho, Diogenes; de Jesus Veiga Carim, Marcelo

    2015-01-01

    Estimates of extinction risk for Amazonian plant and animal species are rare and not often incorporated into land-use policy and conservation planning. We overlay spatial distribution models with historical and projected deforestation to show that at least 36% and up to 57% of all Amazonian tree species are likely to qualify as globally threatened under International Union for Conservation of Nature (IUCN) Red List criteria. If confirmed, these results would increase the number of threatened ...

  4. Morphology, morphometry and ultrastructure of the Amazonian manatee (Sirenia: Trichechidae) spermatozoa

    OpenAIRE

    Amaral,Rodrigo S.; LUCCI, Carolina M.; Fernando C.W. Rosas; Vera M. F. da Silva; Báo,Sônia N.

    2010-01-01

    This study describes the morphological, morphometric and ultrastructural characteristics of the Amazonian manatee Trichechus inunguis (Natterer, 1883) spermatozoon. The spermatozoa were obtained from a urine sample of an adult T. inunguis kept in captivity. The spermatozoa were analyzed by light and transmission electron microscopy. The head of Amazonian manatee spermatozoa had a flat oval shape and a well distinguishable midpiece. The mean dimensions of the spermatozoa were: head length, 7.4...

  5. A marvelous new glassfrog (Centrolenidae, Hyalinobatrachium) from Amazonian Ecuador

    Science.gov (United States)

    Guayasamin, Juan M.; Cisneros-Heredia, Diego F.; Maynard, Ross J.; Lynch, Ryan L.; Culebras, Jaime; Hamilton, Paul S.

    2017-01-01

    Abstract Hyalinobatrachium is a behaviorally and morphologically conserved genus of Neotropical anurans, with several pending taxonomic problems. Using morphology, vocalizations, and DNA, a new species from the Amazonian lowlands of Ecuador is described and illustrated. The new species, Hyalinobatrachium yaku sp. n., is differentiated from all other congenerics by having small, middorsal, dark green spots on the head and dorsum, a transparent pericardium, and a tonal call that lasts 0.27–0.4 s, with a dominant frequency of 5219.3–5329.6 Hz. Also, a mitochondrial phylogeny for the genus is presented that contains the new species, which is inferred as sister to H. pellucidum. Conservation threats to H. yaku sp. n. include habitat destruction and/or pollution mainly because of oil and mining activities. PMID:28769670

  6. A marvelous new glassfrog (Centrolenidae, Hyalinobatrachium from Amazonian Ecuador

    Directory of Open Access Journals (Sweden)

    Juan M. Guayasamin

    2017-05-01

    Full Text Available Hyalinobatrachium is a behaviorally and morphologically conserved genus of Neotropical anurans, with several pending taxonomic problems. Using morphology, vocalizations, and DNA, a new species from the Amazonian lowlands of Ecuador is described and illustrated. The new species, Hyalinobatrachium yaku sp. n., is differentiated from all other congenerics by having small, middorsal, dark green spots on the head and dorsum, a transparent pericardium, and a tonal call that lasts 0.27–0.4 s, with a dominant frequency of 5219.3–5329.6 Hz. Also, a mitochondrial phylogeny for the genus is presented that contains the new species, which is inferred as sister to H. pellucidum. Conservation threats to H. yaku sp. n. include habitat destruction and/or pollution mainly because of oil and mining activities.

  7. Fast demographic traits promote high diversification rates of Amazonian trees

    Science.gov (United States)

    Baker, Timothy R; Pennington, R Toby; Magallon, Susana; Gloor, Emanuel; Laurance, William F; Alexiades, Miguel; Alvarez, Esteban; Araujo, Alejandro; Arets, Eric J M M; Aymard, Gerardo; de Oliveira, Atila Alves; Amaral, Iêda; Arroyo, Luzmila; Bonal, Damien; Brienen, Roel J W; Chave, Jerome; Dexter, Kyle G; Di Fiore, Anthony; Eler, Eduardo; Feldpausch, Ted R; Ferreira, Leandro; Lopez-Gonzalez, Gabriela; van der Heijden, Geertje; Higuchi, Niro; Honorio, Eurídice; Huamantupa, Isau; Killeen, Tim J; Laurance, Susan; Leaño, Claudio; Lewis, Simon L; Malhi, Yadvinder; Marimon, Beatriz Schwantes; Marimon Junior, Ben Hur; Monteagudo Mendoza, Abel; Neill, David; Peñuela-Mora, Maria Cristina; Pitman, Nigel; Prieto, Adriana; Quesada, Carlos A; Ramírez, Fredy; Ramírez Angulo, Hirma; Rudas, Agustin; Ruschel, Ademir R; Salomão, Rafael P; de Andrade, Ana Segalin; Silva, J Natalino M; Silveira, Marcos; Simon, Marcelo F; Spironello, Wilson; ter Steege, Hans; Terborgh, John; Toledo, Marisol; Torres-Lezama, Armando; Vasquez, Rodolfo; Vieira, Ima Célia Guimarães; Vilanova, Emilio; Vos, Vincent A; Phillips, Oliver L; Wiens, John

    2014-01-01

    The Amazon rain forest sustains the world's highest tree diversity, but it remains unclear why some clades of trees are hyperdiverse, whereas others are not. Using dated phylogenies, estimates of current species richness and trait and demographic data from a large network of forest plots, we show that fast demographic traits – short turnover times – are associated with high diversification rates across 51 clades of canopy trees. This relationship is robust to assuming that diversification rates are either constant or decline over time, and occurs in a wide range of Neotropical tree lineages. This finding reveals the crucial role of intrinsic, ecological variation among clades for understanding the origin of the remarkable diversity of Amazonian trees and forests. PMID:24589190

  8. Lipase Activity among Bacteria Isolated from Amazonian Soils

    Directory of Open Access Journals (Sweden)

    André Luis Willerding

    2011-01-01

    Full Text Available The objective of this study was to select lipase-producing bacteria collected from different counties of the Amazon region. Of the 440 bacteria strains, 181 were selected for the lipase assay in qualitative tests at Petri dishes, being 75 (41% lipase positive. The enzymatic index was determined during fifteen days at different temperatures (30°, 35°, 40°, and 45°C. The highest lipase activity was observed within 72 hours at 30°C. Twelve bacteria strains presented an index equal to or greater than the standard used like reference, demonstrating the potential of microbial resource. After the bioassay in Petri dishes, the selected bacteria strains were analyzed in quantitative tests on p-nitrophenyl palmitate (p-NPP. A group of the strains was selected for other phases of study with the use in oleaginous substrates of the Amazonian flora, aiming for the application in processes like oil biotransformation.

  9. Drought sensitivity of Amazonian carbon balance revealed by atmospheric measurements.

    Science.gov (United States)

    Gatti, L V; Gloor, M; Miller, J B; Doughty, C E; Malhi, Y; Domingues, L G; Basso, L S; Martinewski, A; Correia, C S C; Borges, V F; Freitas, S; Braz, R; Anderson, L O; Rocha, H; Grace, J; Phillips, O L; Lloyd, J

    2014-02-06

    Feedbacks between land carbon pools and climate provide one of the largest sources of uncertainty in our predictions of global climate. Estimates of the sensitivity of the terrestrial carbon budget to climate anomalies in the tropics and the identification of the mechanisms responsible for feedback effects remain uncertain. The Amazon basin stores a vast amount of carbon, and has experienced increasingly higher temperatures and more frequent floods and droughts over the past two decades. Here we report seasonal and annual carbon balances across the Amazon basin, based on carbon dioxide and carbon monoxide measurements for the anomalously dry and wet years 2010 and 2011, respectively. We find that the Amazon basin lost 0.48 ± 0.18 petagrams of carbon per year (Pg C yr(-1)) during the dry year but was carbon neutral (0.06 ± 0.1 Pg C yr(-1)) during the wet year. Taking into account carbon losses from fire by using carbon monoxide measurements, we derived the basin net biome exchange (that is, the carbon flux between the non-burned forest and the atmosphere) revealing that during the dry year, vegetation was carbon neutral. During the wet year, vegetation was a net carbon sink of 0.25 ± 0.14 Pg C yr(-1), which is roughly consistent with the mean long-term intact-forest biomass sink of 0.39 ± 0.10 Pg C yr(-1) previously estimated from forest censuses. Observations from Amazonian forest plots suggest the suppression of photosynthesis during drought as the primary cause for the 2010 sink neutralization. Overall, our results suggest that moisture has an important role in determining the Amazonian carbon balance. If the recent trend of increasing precipitation extremes persists, the Amazon may become an increasing carbon source as a result of both emissions from fires and the suppression of net biome exchange by drought.

  10. Large-scale degradation of Amazonian freshwater ecosystems.

    Science.gov (United States)

    Castello, Leandro; Macedo, Marcia N

    2016-03-01

    Hydrological connectivity regulates the structure and function of Amazonian freshwater ecosystems and the provisioning of services that sustain local populations. This connectivity is increasingly being disrupted by the construction of dams, mining, land-cover changes, and global climate change. This review analyzes these drivers of degradation, evaluates their impacts on hydrological connectivity, and identifies policy deficiencies that hinder freshwater ecosystem protection. There are 154 large hydroelectric dams in operation today, and 21 dams under construction. The current trajectory of dam construction will leave only three free-flowing tributaries in the next few decades if all 277 planned dams are completed. Land-cover changes driven by mining, dam and road construction, agriculture and cattle ranching have already affected ~20% of the Basin and up to ~50% of riparian forests in some regions. Global climate change will likely exacerbate these impacts by creating warmer and dryer conditions, with less predictable rainfall and more extreme events (e.g., droughts and floods). The resulting hydrological alterations are rapidly degrading freshwater ecosystems, both independently and via complex feedbacks and synergistic interactions. The ecosystem impacts include biodiversity loss, warmer stream temperatures, stronger and more frequent floodplain fires, and changes to biogeochemical cycles, transport of organic and inorganic materials, and freshwater community structure and function. The impacts also include reductions in water quality, fish yields, and availability of water for navigation, power generation, and human use. This degradation of Amazonian freshwater ecosystems cannot be curbed presently because existing policies are inconsistent across the Basin, ignore cumulative effects, and overlook the hydrological connectivity of freshwater ecosystems. Maintaining the integrity of these freshwater ecosystems requires a basinwide research and policy framework

  11. Emerging acute Chagas Disease in Amazonian Brazil: case reports with serious cardiac involvement

    Directory of Open Access Journals (Sweden)

    Ana Yecê das Neves Pinto

    2004-12-01

    Full Text Available Four cases of serious cardiac attacks by autochthonous Trypanosoma cruzi infection from the Brazilian Amazon are reported; three of them occurred in micro-epidemic episodes. The manifestations included sudden fever, myalgia, dyspnea and signs of heart failure. Diagnosis was confirmed by specific exams, especially QBC (Quantitative Buffy Coat and natural xenodiagnosis. Despite treatment with benznidazol, three patients died with serious myocarditis, renal failure and cardiac tamponade. The authors call attention to the emergence of this disease and reveal a previously unknown pathogenicity of T. cruzi strains in this area, added to a non-usual transmission form.

  12. ORCHID BEES (APIDAE: EUGLOSSINI IN A FOREST FRAGMENT IN THE ECOTONE CERRADO-AMAZONIAN FOREST, BRAZIL

    Directory of Open Access Journals (Sweden)

    José Max Barbosa de OLIVEIRA-JUNIOR

    2015-01-01

    Full Text Available En este trabajo se presenta información sobre la riqueza de especies y abundancia de Euglossini en la zona de transición entre el Cerrado y la selva amazónica, en la cuenca del río Xingu. Las muestras se recogieron en un fragmento de bosque en el municipio de Ribeirão Cascalheira, nordeste de Mato Grosso, Brasil, entre el 1 y 5 de noviembre de 2011. Las sustancias puras de benzoato de bencilo, 1,8 cineol, eugenol y la vainillina fueron utilizadas como cebos para atraer los machos usando red de insectos aunque el salicilato de metilo se utilizó en trampas pasivas. Un total de 168 machos pertenecientes a cuatro géneros fueron registrados, distribuidos en 16 especies. La mayor riqueza de especies se registró en el género Euglossa , aunque Eulaema nigrita fue la especie más abundante en la comunidad. La riqueza de especies varió entre el borde y el primer punto dentro del fragmento. Los machos de abejas de orquídeas eran más activos entre 10:00-11:00 h, y el 1,8 cineol fue la sustancia pura más atractiva. El fragmento estudiado contenía un alto grado de riqueza de especies de abejas de orquídeas en una región de heterogeneidad ambiental extensa, que sigue siendo en gran parte desconocido con relación a su fauna de insectos polinizadores y merece la atención para la elaboración de nuevos inventarios.

  13. Emerging acute Chagas Disease in Amazonian Brazil: case reports with serious cardiac involvement

    Directory of Open Access Journals (Sweden)

    Ana Yecê das Neves Pinto

    Full Text Available Four cases of serious cardiac attacks by autochthonous Trypanosoma cruzi infection from the Brazilian Amazon are reported; three of them occurred in micro-epidemic episodes. The manifestations included sudden fever, myalgia, dyspnea and signs of heart failure. Diagnosis was confirmed by specific exams, especially QBC (Quantitative Buffy Coat and natural xenodiagnosis. Despite treatment with benznidazol, three patients died with serious myocarditis, renal failure and cardiac tamponade. The authors call attention to the emergence of this disease and reveal a previously unknown pathogenicity of T. cruzi strains in this area, added to a non-usual transmission form.

  14. Distinct population structure for co-occurring Anopheles goeldii and Anopheles triannulatus in Amazonian Brazil

    Directory of Open Access Journals (Sweden)

    Sascha Naomi McKeon

    2013-08-01

    Full Text Available To evaluate whether environmental heterogeneity contributes to the genetic heterogeneity in Anopheles triannulatus, larval habitat characteristics across the Brazilian states of Roraima and Pará and genetic sequences were examined. A comparison with Anopheles goeldii was utilised to determine whether high genetic diversity was unique to An. triannulatus. Student t test and analysis of variance found no differences in habitat characteristics between the species. Analysis of population structure of An. triannulatus and An. goeldii revealed distinct demographic histories in a largely overlapping geographic range. Cytochrome oxidase I sequence parsimony networks found geographic clustering for both species; however nuclear marker networks depicted An. triannulatus with a more complex history of fragmentation, secondary contact and recent divergence. Evidence of Pleistocene expansions suggests both species are more likely to be genetically structured by geographic and ecological barriers than demography. We hypothesise that niche partitioning is a driving force for diversity, particularly in An. triannulatus.

  15. The impact of deforestation in the Amazonian atmospheric radiative balance: a remote sensing assessment

    Directory of Open Access Journals (Sweden)

    E. T. Sena

    2012-06-01

    Full Text Available This paper addresses the Amazonian radiative budget 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 Amazon was obtained for the biomass burning season of each year. It was observed that for high AOD (larger than 1 at 550 nm the imbalance in the 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−2550 nm and −9.3 ± 1.7 W m−2550 nm were calculated for the mean daily aerosol forcing efficiencies over forest and savannah-like vegetation respectively. The overall mean annual albedo-change radiative forcing due to deforestation over the state of Rondônia, Brazil, was determined as −7.3 ± 0.9 W m−2. Biomass burning aerosols impact the radiative

  16. Bradyrhizobium manausense sp. nov., isolated from effective nodules of Vigna unguiculata grown in Brazilian Amazonian rainforest soils.

    Science.gov (United States)

    Silva, Flavia V; De Meyer, Sofie E; Simões-Araújo, Jean L; Barbé, Tatiane da Costa; Xavier, Gustavo R; O'Hara, Graham; Ardley, Julie K; Rumjanek, Norma G; Willems, Anne; Zilli, Jerri E

    2014-07-01

    Root nodule bacteria were trapped within cowpea (Vigna unguiculata) in soils with different cultivation histories collected from the Amazonian rainforest in northern Brazil. Analysis of the 16S rRNA gene sequences of six strains (BR 3351(T), BR 3307, BR 3310, BR 3315, BR 3323 BR and BR 3361) isolated from cowpea nodules showed that they formed a distinct group within the genus Bradyrhizobium, which was separate from previously identified type strains. Phylogenetic analyses of three housekeeping genes (glnII, recA and rpoB) revealed that Bradyrhizobium huanghuaihaiense CCBAU 23303(T) was the most closely related type strain (96% sequence similarity or lower). Chemotaxonomic data, including fatty acid profiles (predominant fatty acids being C16 : 0 and summed feature 8), the slow growth rate and carbon compound utilization patterns supported the assignment of the strains to the genus Bradyrhizobium. The results of DNA-DNA hybridizations, antibiotic resistance and physiological tests differentiated these novel strains from the most closely related species of the genus Bradyrhizobium with validly published names. Symbiosis-related genes for nodulation (nodC) and nitrogen fixation (nifH) grouped the novel strains of the genus Bradyrhizobium together with Bradyrhizobium iriomotense strain EK05(T), with 94% and 96% sequence similarity, respectively. Based on these data, these six strains represent a novel species for which the name Brabyrhizobium manausense sp. nov. (BR 3351(T) = HAMBI 3596(T)), is proposed.

  17. Effects of physical activity at work and life-style on sleep in workers from an Amazonian Extractivist Reserve

    Directory of Open Access Journals (Sweden)

    Andressa Juliane Martins

    2016-10-01

    Full Text Available Physical activity has been recommended as a strategy for improving sleep. Nevertheless, physical effort at work might not be not the ideal type of activity to promote sleep quality. The aim of this study was to evaluate the effects of type of job (low vs. high physical effort and life-style on sleep of workers from an Amazonian Extractivist Reserve, Brazil. A cross-sectional study of 148 low physical activity (factory workers and 340 high physical activity (rubber tappers was conducted between September and November 2011. The workers filled out questionnaires collecting data on demographics (sex, age, occupation, marital status and children, health (reported morbidities, sleep disturbances, musculoskeletal pain and body mass index and life-style (smoking, alcohol use and practice of leisure-time physical activity. Logistic regression models were applied with the presence of sleep disturbances as the primary outcome variable. The prevalence of sleep disturbances among factory workers and rubber tappers was 15.5% and 27.9%, respectively. The following independent variables of the analysis were selected based on a univariate model (p40 years, and having musculoskeletal pain (≥5 symptoms. Rubber tapper work, owing to greater physical effort, pain and musculoskeletal fatigue, was associated with sleep disturbances. Being female and older than 40 years were also predictors of poor sleep. In short, these findings suggest that demanding physical exertion at work may not improve sleep quality.

  18. Root Niche Separation as Strategy of Avoidance of Seasonal Drought Stress in a Mature Amazonian Forest (Invited)

    Science.gov (United States)

    Ivanov, V. Y.; Hutyra, L.; Wofsy, S. C.; Munger, J. W.; Saleska, S. R.; De Oliveira, R., Jr.; Camargo, P. B.; Fatichi, S.

    2013-12-01

    Large areas of Amazonian evergreen forests experience seasonal droughts extending for three or more months, and show maximum rates of photosynthesis and evapotranspiration during dry intervals. This apparent resilience is belied by disproportionate mortality of the large trees in manipulations that reduce wet season rainfall, occurring after 2-3 years of treatment. The goal of this study is to characterize the mechanisms that produce these contrasting ecosystem responses. A mechanistic vegetation-hydrology model is developed to test the roles of deep roots and the possibility of 'root niche separation,' in which roots of overstory trees extend to depth, where during the dry season they use water stored from wet season precipitation, while roots of understory trees are concentrated in shallow layers that access dry season precipitation directly. Observational data on canopy phenology, energy fluxes, soil moisture, and soil and root structure from the Tapajos National Forest, Brazil, provided comprehensive observational constraints on the model. Results strongly suggest that deep roots with root niche separation adaptations explain both the observed resilience during seasonal drought and the vulnerability of canopy-dominant trees to extended deficits of wet season rainfall. These mechanisms appear to provide an adaptive strategy that enhances productivity of the largest trees in the face of their disproportionate heat loads and water demand in the dry season. A sensitivity analysis exploring how wet season rainfall affects the stability of the rainforest system is presented.

  19. Changing patterns of fire occurrence in proximity to forest edges, roads and rivers between NW Amazonian countries

    Directory of Open Access Journals (Sweden)

    D. Armenteras

    2017-06-01

    Full Text Available Tropical forests in NW Amazonia are highly threatened by the expansion of the agricultural frontier and subsequent deforestation. Fire is used, both directly and indirectly, in Brazilian Amazonia to propagate deforestation and increase forest accessibility. Forest fragmentation, a measure of forest degradation, is also attributed to fire occurrence in the tropics. However, outside the Brazilian Legal Amazonia the role of fire in increasing accessibility and forest fragmentation is less explored. In this study, we compared fire regimes in five countries that share this tropical biome in the most north-westerly part of the Amazon Basin (Venezuela, Colombia, Ecuador, Peru and Brazil. We analysed spatial differences in the timing of peak fire activity and in relation to proximity to roads and rivers using 12 years of MODIS active fire detections. We also distinguished patterns of fire in relation to forest fragmentation by analysing fire distance to the forest edge as a measure of fragmentation for each country. We found significant hemispheric differences in peak fire occurrence with the highest number of fires in the south in 2005 vs. 2007 in the north. Despite this, both hemispheres are equally affected by fire. We also found difference in peak fire occurrence by country. Fire peaked in February in Colombia and Venezuela, whereas it peaked in September in Brazil and Peru, and finally Ecuador presented two fire peaks in January and October. We confirmed the relationship between fires and forest fragmentation for all countries and also found significant differences in the distance between the fire and the forest edge for each country. Fires were associated with roads and rivers in most countries. These results can inform land use planning at the regional, national and subnational scales to minimize the contribution of road expansion and subsequent access to the Amazonian natural resources to fire occurrence and the associated deforestation and

  20. Changing patterns of fire occurrence in proximity to forest edges, roads and rivers between NW Amazonian countries

    Science.gov (United States)

    Armenteras, Dolors; Barreto, Joan Sebastian; Tabor, Karyn; Molowny-Horas, Roberto; Retana, Javier

    2017-06-01

    Tropical forests in NW Amazonia are highly threatened by the expansion of the agricultural frontier and subsequent deforestation. Fire is used, both directly and indirectly, in Brazilian Amazonia to propagate deforestation and increase forest accessibility. Forest fragmentation, a measure of forest degradation, is also attributed to fire occurrence in the tropics. However, outside the Brazilian Legal Amazonia the role of fire in increasing accessibility and forest fragmentation is less explored. In this study, we compared fire regimes in five countries that share this tropical biome in the most north-westerly part of the Amazon Basin (Venezuela, Colombia, Ecuador, Peru and Brazil). We analysed spatial differences in the timing of peak fire activity and in relation to proximity to roads and rivers using 12 years of MODIS active fire detections. We also distinguished patterns of fire in relation to forest fragmentation by analysing fire distance to the forest edge as a measure of fragmentation for each country. We found significant hemispheric differences in peak fire occurrence with the highest number of fires in the south in 2005 vs. 2007 in the north. Despite this, both hemispheres are equally affected by fire. We also found difference in peak fire occurrence by country. Fire peaked in February in Colombia and Venezuela, whereas it peaked in September in Brazil and Peru, and finally Ecuador presented two fire peaks in January and October. We confirmed the relationship between fires and forest fragmentation for all countries and also found significant differences in the distance between the fire and the forest edge for each country. Fires were associated with roads and rivers in most countries. These results can inform land use planning at the regional, national and subnational scales to minimize the contribution of road expansion and subsequent access to the Amazonian natural resources to fire occurrence and the associated deforestation and carbon emissions.

  1. Spotlight: Brazil.

    Science.gov (United States)

    Carter, M

    1996-08-01

    Brazil is South America's largest country and home to nearly half of the continent's people. Despite solid economic growth, Brazil has one of the world's widest income disparities. In the early 1990s, nearly 40% of urban and 66% of rural Brazilians lived in poverty. The streets of Brazil's cities are home to a large population of street children. Although it is difficult to estimate, 10 million children and youths may be either homeless or making a meager living off of the streets. Street children may be linked to prostitution and drugs and be the targets or perpetrators of violence. Child labor is an issue in Brazil. Today an estimated 30% of rural children and 9% of urban children ages 10-13 work in the formal economy. In some rural areas, 60% of workers are ages 5-17. Child labor also contributes to Brazil's relatively low educational attainment levels. UNICEF estimates that around 1990 only 1/3 of all Brazilian children continued on to secondary school, compared to 74% and 47%, respectively, for the Latin America and Caribbean regions. Immunization rates among Brazil's children are rising but still lag slightly behind regional averages. The mortality rate for children under age 5 decreased dramatically from 181 deaths for every 1000 live births in 1960 to 61/1000 in 1994. During the same time period, the average number of children born to a woman during her lifetime dropped from 6.2 to 2.8. This fertility decline is related in part to increased access to and acceptance of family planning. Contraceptive prevalence, including traditional and modern methods, is around 66%, with female sterilization and the pill being the most popular methods. Brazil's abortion rates are high, despite laws limiting access to abortion services. One estimate suggests that about 30% of all pregnancies are terminated through abortion each year.

  2. A Miocene hyperdiverse crocodylian community reveals peculiar trophic dynamics in proto-Amazonian mega-wetlands

    Science.gov (United States)

    Salas-Gismondi, Rodolfo; Flynn, John J.; Baby, Patrice; Tejada-Lara, Julia V.; Wesselingh, Frank P.; Antoine, Pierre-Olivier

    2015-01-01

    Amazonia contains one of the world's richest biotas, but origins of this diversity remain obscure. Onset of the Amazon River drainage at approximately 10.5 Ma represented a major shift in Neotropical ecosystems, and proto-Amazonian biotas just prior to this pivotal episode are integral to understanding origins of Amazonian biodiversity, yet vertebrate fossil evidence is extraordinarily rare. Two new species-rich bonebeds from late Middle Miocene proto-Amazonian deposits of northeastern Peru document the same hyperdiverse assemblage of seven co-occurring crocodylian species. Besides the large-bodied Purussaurus and Mourasuchus, all other crocodylians are new taxa, including a stem caiman—Gnatusuchus pebasensis—bearing a massive shovel-shaped mandible, procumbent anterior and globular posterior teeth, and a mammal-like diastema. This unusual species is an extreme exemplar of a radiation of small caimans with crushing dentitions recording peculiar feeding strategies correlated with a peak in proto-Amazonian molluscan diversity and abundance. These faunas evolved within dysoxic marshes and swamps of the long-lived Pebas Mega-Wetland System and declined with inception of the transcontinental Amazon drainage, favouring diversification of longirostrine crocodylians and more modern generalist-feeding caimans. The rise and demise of distinctive, highly productive aquatic ecosystems substantially influenced evolution of Amazonian biodiversity hotspots of crocodylians and other organisms throughout the Neogene. PMID:25716785

  3. The Sound-Symbolic Expression of Animacy in Amazonian Ecuador

    Directory of Open Access Journals (Sweden)

    Janis B. Nuckolls

    2010-03-01

    Full Text Available Several anthropologists of Amazonian societies in Ecuador have claimed that for Achuar [1] and Quichua speaking Runa [2-4] there is no fundamental distinction between humans on the one hand, and plants and animals on the other. A related observation is that Runa and Achuar people share an animistic cosmology whereby animals, plants, and even seemingly inert entities such as rocks and stones are believed to have a life force or essence with a subjectivity that can be expressed. This paper will focus on Quichua speaking Runa to seek linguistic evidence for animacy by examining the sound-symbolic properties of a class of expressions called ideophones. I argue that structural features of ideophones such as canonical length and diversity of sound segments as well as type of sound segments, help express the animism of the Runa lifeworld. Moreover, although these features are not indicative of any essential distinctions between plants and animals, they may be indicative of a scalar view of animacy, along the lines suggested by Descola who first proposed a continuum or ‘ladder of animacy’ for the Achuar [1, pp. 321-326]. Ideophones, then, may be understood as one set of linguistic tools for coming to terms with the diversity of their ecological setting, a setting which spans highly animate humans and animals, through less animate plants, trees, and rocks.

  4. Pesticide use and biodiversity conservation in the Amazonian agricultural frontier.

    Science.gov (United States)

    Schiesari, Luis; Waichman, Andrea; Brock, Theo; Adams, Cristina; Grillitsch, Britta

    2013-06-05

    Agricultural frontiers are dynamic environments characterized by the conversion of native habitats to agriculture. Because they are currently concentrated in diverse tropical habitats, agricultural frontiers are areas where the largest number of species is exposed to hazardous land management practices, including pesticide use. Focusing on the Amazonian frontier, we show that producers have varying access to resources, knowledge, control and reward mechanisms to improve land management practices. With poor education and no technical support, pesticide use by smallholders sharply deviated from agronomical recommendations, tending to overutilization of hazardous compounds. By contrast, with higher levels of technical expertise and resources, and aiming at more restrictive markets, large-scale producers adhered more closely to technical recommendations and even voluntarily replaced more hazardous compounds. However, the ecological footprint increased significantly over time because of increased dosage or because formulations that are less toxic to humans may be more toxic to other biodiversity. Frontier regions appear to be unique in terms of the conflicts between production and conservation, and the necessary pesticide risk management and risk reduction can only be achieved through responsibility-sharing by diverse stakeholders, including governmental and intergovernmental organizations, NGOs, financial institutions, pesticide and agricultural industries, producers, academia and consumers.

  5. Evidence for Middle Amazonian catastrophic flooding and glaciation on Mars

    Science.gov (United States)

    Rodríguez, J. Alexis P.; Gulick, Virginia C.; Baker, Victor R.; Platz, Thomas; Fairén, Alberto G.; Miyamoto, Hideaki; Kargel, Jeffrey S.; Rice, James W.; Glines, Natalie

    2014-11-01

    Early geologic investigations of Mars revealed some of the largest channels in the Solar System (outflow channels), which appear to have mostly developed ∼3 byr ago. These channels have been the subject of much scientific inquiry since the 1970s and proposed formative processes included surface erosion by catastrophic floods, glaciers, debris flows and lava flows. Based on the analysis of newly acquired Mars Reconnaissance Orbiter (MRO) Context (CTX, 5.15-5.91 m/pixel) and High Resolution Imaging Science Experiment (HiRISE, 25-50 cm/pixel) image data, we have identified a few locations contained within relatively narrow canyons of the southern circum-Chryse outflow channels that retain well-preserved decameter/hectometer-scale landform assemblages. These terrains include landforms consistent in shape, dimension and overall assemblage to those produced by catastrophic floods, and at one location, to glacial morphologies. Impact crater statistics for four of these surfaces, located within upstream, midstream and downstream outflow channel surfaces, yield an age estimate of ∼600 myr. This suggests that the southern circum-Chryse outflow channels were locally resurfaced by some of the most recent catastrophic floods on the planet, and that these floods coexisted within regional glacier environments as recently as during the Middle Amazonian.

  6. Carbon Dioxide and Methane Evasion from Amazonian Rivers and Lakes

    Science.gov (United States)

    Melack, J. M.; Barbosa, P.; Schofield, V.; Amaral, J.; Forsberg, B.; Farjalla, V.

    2013-12-01

    Floodplains, with their mosaic of aquatic habitats, constitute the majority of the wetlands of South America. We report 1) estimates of CH4 and CO2 flux from Amazonian floodplain lakes and rivers during low, rising and high water periods, and 2) identify environmental factors regulating these fluxes. We sampled 10 floodplain lakes, 4 tributaries of Solimões River, 6 stations on the Solimões main stem and 1 station on the Madeira, Negro and Amazonas rivers. Diffusive fluxes were measured with static floating chambers. CH4 fluxes were highly variable, with the majority of the values lower than 5 mmol m-2 d-1. For the lakes, no significant differences among the periods were found. CH4 concentration in the water and water temperature were the two main environmental factors regulating the diffusive flux. Our results highlight the importance of considering both the spatial and temporal scales when estimating CH4 fluxes for a region. CO2 fluxes from water to atmosphere ranged between 327 and -21 mmol m-2 d-1, averaging 58 mmol m-2 d-1. We found higher evasion rates in lakes than in rivers. For both systems the lowest rates were found in low water. pH and dissolved oxygen, phosphorous and organic carbon were the main factors correlated to CO2 evasion from the water bodies.

  7. Sensitivities of Amazonian clouds to aerosols and updraft speed

    Science.gov (United States)

    Cecchini, Micael A.; Machado, Luiz A. T.; Andreae, Meinrat O.; Martin, Scot T.; Albrecht, Rachel I.; Artaxo, Paulo; Barbosa, Henrique M. J.; Borrmann, Stephan; Fütterer, Daniel; Jurkat, Tina; Mahnke, Christoph; Minikin, Andreas; Molleker, Sergej; Pöhlker, Mira L.; Pöschl, Ulrich; Rosenfeld, Daniel; Voigt, Christiane; Weinzierl, Bernadett; Wendisch, Manfred

    2017-08-01

    The effects of aerosol particles and updraft speed on warm-phase cloud microphysical properties are studied in the Amazon region as part of the ACRIDICON-CHUVA experiment. Here we expand the sensitivity analysis usually found in the literature by concomitantly considering cloud evolution, putting the sensitivity quantifications into perspective in relation to in-cloud processing, and by considering the effects on droplet size distribution (DSD) shape. Our in situ aircraft measurements over the Amazon Basin cover a wide range of particle concentration and thermodynamic conditions, from the pristine regions over coastal and forested areas to the southern Amazon, which is highly polluted from biomass burning. The quantitative results show that particle concentration is the primary driver for the vertical profiles of effective diameter and droplet concentration in the warm phase of Amazonian convective clouds, while updraft speeds have a modulating role in the latter and in total condensed water. The cloud microphysical properties were found to be highly variable with altitude above cloud base, which we used as a proxy for cloud evolution since it is a measure of the time droplets that were subject to cloud processing. We show that DSD shape is crucial in understanding cloud sensitivities. The aerosol effect on DSD shape was found to vary with altitude, which can help models to better constrain the indirect aerosol effect on climate.

  8. Oxidative mitigation of aquatic methane emissions in large Amazonian rivers.

    Science.gov (United States)

    Sawakuchi, Henrique O; Bastviken, David; Sawakuchi, André O; Ward, Nicholas D; Borges, Clovis D; Tsai, Siu M; Richey, Jeffrey E; Ballester, Maria Victoria R; Krusche, Alex V

    2016-03-01

    The flux of methane (CH4 ) from inland waters to the atmosphere has a profound impact on global atmospheric greenhouse gas (GHG) levels, and yet, strikingly little is known about the dynamics controlling sources and sinks of CH4 in the aquatic setting. Here, we examine the cycling and flux of CH4 in six large rivers in the Amazon basin, including the Amazon River. Based on stable isotopic mass balances of CH4 , inputs and outputs to the water column were estimated. We determined that ecosystem methane oxidation (MOX) reduced the diffusive flux of CH4 by approximately 28-96% and varied depending on hydrologic regime and general geochemical characteristics of tributaries of the Amazon River. For example, the relative amount of MOX was maximal during high water in black and white water rivers and minimal in clear water rivers during low water. The abundance of genetic markers for methane-oxidizing bacteria (pmoA) was positively correlated with enhanced signals of oxidation, providing independent support for the detected MOX patterns. The results indicate that MOX in large Amazonian rivers can consume from 0.45 to 2.07 Tg CH4 yr(-1) , representing up to 7% of the estimated global soil sink. Nevertheless, climate change and changes in hydrology, for example, due to construction of dams, can alter this balance, influencing CH4 emissions to atmosphere.

  9. Branchfall dominates annual carbon flux across lowland Amazonian forests

    Science.gov (United States)

    Marvin, David C.; Asner, Gregory P.

    2016-09-01

    Tropical forests play an important role in the global carbon cycle, but knowledge of interannual variation in the total tropical carbon flux and constituent carbon pools is highly uncertain. One such pool, branchfall, is an ecologically important dynamic with links to nutrient cycling, forest productivity, and drought. Identifying and quantifying branchfall over large areas would reveal the role of branchfall in carbon and nutrient cycling. Using data from repeat airborne light detection and ranging campaigns across a wide array of lowland Amazonian forest landscapes totaling nearly 100 000 ha, we find that upper canopy gaps—driven by branchfall—are pervasive features of every landscape studied, and are seven times more frequent than full tree mortality. Moreover, branchfall comprises a major carbon source on a landscape basis, exceeding that of tree mortality by 21%. On a per hectare basis, branchfall and tree mortality result in 0.65 and 0.72 Mg C ha-1 yr-1 gross source of carbon to the atmosphere, respectively. Reducing uncertainties in annual gross rates of tropical forest carbon flux, for example by incorporating large-scale branchfall dynamics, is crucial for effective policies that foster conservation and restoration of tropical forests. Additionally, large-scale branchfall mapping offers ecologists a new dimension of disturbance monitoring and potential new insights into ecosystem structure and function.

  10. Deep plant-derived carbon storage in Amazonian podzols

    Directory of Open Access Journals (Sweden)

    C. R. Montes

    2010-10-01

    Full Text Available Equatorial podzols are soils characterized by thick sandy horizons overlying more clayey horizons. Organic matter produced in the topsoil is transferred in depth through the sandy horizons and accumulate at the transition, at a depth varying from 1 to more than 3 m, forming deep horizons rich in organic matter (Bh horizons. Although they cover great surfaces in the equatorial zone, these soils are still poorly known. Studying podzols from Amazonia, we found out that the deep Bh horizons in poorly drained podzol areas have a thickness higher than 1 m and store unexpected amounts of carbon. The average for the studied area was 66.7 ± 5.8 kg C m−2 for the deep Bh and 86.8 ± 7.1 kg C m−2 for the whole profile. Extrapolating to the podzol areas of the whole Amazonian Basin has been possible thanks to digital maps, giving an order of magnitude around 13.6 ± 1.1 Pg C, at least 12.3 Pg C higher than previous estimates. This assessment should be refined by additional investigations, not only in Amazonia but in all equatorial areas where podzols have been identified. Because of the lack of knowledge on the quality and behaviour of the podzol organic matter, the question of the feedback between the climate and the equatorial podzol carbon cycle is open.

  11. Biotransformations of terpenes by fungi from Amazonian citrus plants.

    Science.gov (United States)

    Moreno Rueda, Maria Gabriela; Guerrini, Alessandra; Giovannini, Pier Paolo; Medici, Alessandro; Grandini, Alessandro; Sacchetti, Gianni; Pedrini, Paola

    2013-10-01

    The biotransformations of (RS)-linalool (1), (S)-citronellal (2), and sabinene (3) with fungi isolated from the epicarp of fruits of Citrus genus of the Amazonian forest (i.e., C. limon, C. aurantifolia, C. aurantium, and C. paradisiaca) are reported. The more active strains have been characterized, and they belong to the genus Penicillium and Fusarium. Different biotransformation products have been obtained depending on fungi and substrates. (RS)-Linalool (1) afforded the (E)- and (Z)-furanlinalool oxides (7 and 8, resp.; 39 and 37% yield, resp.) with Fusarium sp. (1D2), 6-methylhept-5-en-2-one (4; 49%) with F. fujikuroi, and 1-methyl-1-(4-methypentyl)oxiranemethanol (6; 42%) with F. concentricum. (S)-Citronellal (2) gave (S)-citronellol (12; 36-76%) and (S)-citronellic acid (11; 5-43%) with Fusarium species, while diastereoisomeric p-menthane-3,8-diols 13 and 14 (20 and 50% yield, resp.) were obtained as main products with Penicillium paxilli. Finally, both Fusarium species and P. paxilli biotransformed sabinene (3) to give mainly 4-terpineol (19; 23-56%), and (Z)- and (E)-sabinene hydrates (17 (3-21%) and 18 (11-17%), resp.).

  12. Ocurrence of Cryptosporidium spp. in Amazonian manatees (Trichechus inunguis, Natterer, 1883

    Directory of Open Access Journals (Sweden)

    Maria Aparecida da Glória Faustino

    2007-09-01

    Full Text Available The apicomplexa protozoa Cryptosporidium infects several mammals, including terrestrial and aquatic species. In the epidemiology of this infection, the ingestion of water and/or food contamined with oocysts comprises the main mechanism of transmission to susceptible animals. Among the Sirenians, the occurrence of this coccidium has been reported in dugongs (Dugong dugon and Antillean manatee (Trichechus manatus manatus. The present study was conducted with the aim of verifying the occurrence of Cryptosporidium spp. in Amazonian manatee. For this purpose, fecal samples were collected from ten free-ranging Amazonian manatees, two specimens in captivity, and 103 supernatants fecal samples. The samples were processed by the sedimentation method in formol-ether and Kinyoun stain technique for the presence of Cryptosporidium spp.. The positive samples were then submitted to Direct Immunoflorescence Test. The results showed 4.34% (05/115 of positive samples. This is the first report of Cryptosporidium spp. in the Amazonian manatee.

  13. Equatorial Pacific forcing of western Amazonian precipitation during Heinrich Stadial 1

    Science.gov (United States)

    Zhang, Yancheng; Zhang, Xu; Chiessi, Cristiano M.; Mulitza, Stefan; Zhang, Xiao; Lohmann, Gerrit; Prange, Matthias; Behling, Hermann; Zabel, Matthias; Govin, Aline; Sawakuchi, André O.; Cruz, Francisco W.; Wefer, Gerold

    2016-01-01

    Abundant hydroclimatic evidence from western Amazonia and the adjacent Andes documents wet conditions during Heinrich Stadial 1 (HS1, 18–15 ka), a cold period in the high latitudes of the North Atlantic. This precipitation anomaly was attributed to a strengthening of the South American summer monsoon due to a change in the Atlantic interhemispheric sea surface temperature (SST) gradient. However, the physical viability of this mechanism has never been rigorously tested. We address this issue by combining a thorough compilation of tropical South American paleorecords and a set of atmosphere model sensitivity experiments. Our results show that the Atlantic SST variations alone, although leading to dry conditions in northern South America and wet conditions in northeastern Brazil, cannot produce increased precipitation over western Amazonia and the adjacent Andes during HS1. Instead, an eastern equatorial Pacific SST increase (i.e., 0.5–1.5 °C), in response to the slowdown of the Atlantic Meridional Overturning Circulation during HS1, is crucial to generate the wet conditions in these regions. The mechanism works via anomalous low sea level pressure over the eastern equatorial Pacific, which promotes a regional easterly low-level wind anomaly and moisture recycling from central Amazonia towards the Andes. PMID:27779213

  14. Amazonian malaria: asymptomatic human reservoirs, diagnostic challenges, environmentally driven changes in mosquito vector populations, and the mandate for sustainable control strategies.

    Science.gov (United States)

    da Silva-Nunes, Mônica; Moreno, Marta; Conn, Jan E; Gamboa, Dionicia; Abeles, Shira; Vinetz, Joseph M; Ferreira, Marcelo U

    2012-03-01

    Across the Americas and the Caribbean, nearly 561,000 slide-confirmed malaria infections were reported officially in 2008. The nine Amazonian countries accounted for 89% of these infections; Brazil and Peru alone contributed 56% and 7% of them, respectively. Local populations of the relatively neglected parasite Plasmodium vivax, which currently accounts for 77% of the regional malaria burden, are extremely diverse genetically and geographically structured. At a time when malaria elimination is placed on the public health agenda of several endemic countries, it remains unclear why malaria proved so difficult to control in areas of relatively low levels of transmission such as the Amazon Basin. We hypothesize that asymptomatic parasite carriage and massive environmental changes that affect vector abundance and behavior are major contributors to malaria transmission in epidemiologically diverse areas across the Amazon Basin. Here we review available data supporting this hypothesis and discuss their implications for current and future malaria intervention policies in the region. Given that locally generated scientific evidence is urgently required to support malaria control interventions in Amazonia, we briefly describe the aims of our current field-oriented malaria research in rural villages and gold-mining enclaves in Peru and a recently opened agricultural settlement in Brazil.

  15. Game depletion hypothesis of amazonian adaptation: data from a native community.

    Science.gov (United States)

    Vickers, W T

    1988-03-25

    The low population densities and impermanent settlements of Amazonian Indians are often interpreted as adaptations to a fauna that offers limited protein resources and is rapidly depleted by hunting. Data spanning the 10-year life cycle of one northwestern Amazonian settlement show that variations in hunt yields result from temporal variations in peccary (Tayassu pecari and T. tajacu) kills that appear extrinsic to native population size. After 10 years, hunting success remained high and the kill rates for most prey did not suggest depletion. An array of environmental factors accounts for the incipient settlement relocation observed.

  16. Commonness of Amazonian palm (Arecaceae) species: Cross-scale links and potential determinants

    DEFF Research Database (Denmark)

    Kristiansen, Thea; Svenning, J.-C.; Grández, César

    2009-01-01

    The mechanisms that cause variation in commonness (abundances and range sizes) of species remain debated in ecology, and a repeatedly observed pattern is the positive relation between local abundances and larger scale range sizes. We used the Amazonian palm species (Arecaceae) to investigate...... commonness in the Amazonian palm flora appear to be scale-dependent, with the unrelated local scale abundance and continental range size probably being controlled by different driving factors. Interestingly, commonness at the intermediate, landscape scale seems linked to both the smaller and the larger scale...

  17. Paepalanthus sphaeroides, a new species of Eriocaulaceae from the Atlantic Forest, Brazil

    NARCIS (Netherlands)

    Trovó, M.; Echternacht, L.; Sano, P.T.

    2012-01-01

    We describe and illustrate Paepalanthus sphaeroides (Eriocaulaceae, Paepalanthoideae) from the Mantiqueira Range in South-eastern Brazil and compare it with the morphologically most similar species: Paepalanthus aequalis and Paepalanthus eriophaeus. Paepalanthus sphaeroides has unique membranaceous

  18. C Cryoco onserv vation of plan nt germ mplasm m nativ ve to B Brazil

    African Journals Online (AJOL)

    SAM

    the risk of disease and plagues striking, besides the need to perform ... development and economic growth Brazil has been going through in the ... their habitat, and the irregularity of seed production ...... studies from Eastern Australia. In Vitro ...

  19. Young Valley Networks on Mars: Persistent Flow of Water in Lyot Crater, a Distinctive Amazonian Impact Basin Microenvironment

    Science.gov (United States)

    Dickson, J.; Fassett, C.; Head, J.

    2008-09-01

    Introduction While Amazonian fluvial landforms are not abundant on Mars, remote sensing data have revealed details regarding the role of ice in non-polar regions in the Amazonian. Evidence includes 1) deposits interpreted to be remnants of cold-based glaciers at low- and mid-latitudes [1-6]; 2) mantling deposits interpreted to be a desiccating layer of ground ice [7- 8]; 3) detection of hydrogen (inferred to be bound as water ice) in soil in the mid- and high-latitudes in each hemisphere [9-10]; and 4) viscous flow features interpreted to be the product of glacial-like flow along steep valley/crater walls [11-12]. The climate of Mars straddles the triple point, which motivated us to investigate the most-likely locations/microclimates for melting of these surface/near-surface ice features [13-14]: large-scale impact craters at low elevations and mid-latitudes, which provide 1) relatively high surface pressure; 2) increased solor insolation; and 3) potential residual thermal anomalies from the impact event. Lyot Crater, a ~215 km peak-ring impact basin in the northern lowlands of Mars (50°N, 30°E), provides an environment that meets these constraints. We analyzed recently obtained CTX data to document evidence of remnant glacial deposits and surface features that appear indicative of melting and drainage. Description The floor of Lyot exhibits several networks of sinuous valleys that have been incised exclusively into a pervasive stippled mantling unit (Fig. 1). Twenty separate networks are observed in CTX and THEMIS data, 15 of which occur in the eastern half of Lyot. The valleys range in length from short, 2 km long isolated valleys to 50 km long networks of multiple valleys that have widths that average ~250 m. Valley floors are smooth at CTX resolution, in contrast to the adjacent stippled mantling unit (Fig. 1). Profiles extracted from the Mars Orbiter Laser Altimeter (MOLA) data set show that, without exception, the valleys follow the local topographic

  20. Amazonian Buriti oil: chemical characterization and antioxidant potential

    Directory of Open Access Journals (Sweden)

    Speranza, P.

    2016-06-01

    Full Text Available Buriti oil is an example of an Amazonian palm oil of economic importance. The local population uses this oil for the prevention and treatment of different diseases; however, there are few studies in the literature that evaluate its properties. In this study, detailed chemical and antioxidant properties of Buriti oil were determined. The predominant fatty acid was oleic acid (65.6% and the main triacylglycerol classes were tri-unsaturated (50.0% and di-unsaturated-mono-saturated (39.3% triacylglycerols. The positional distribution of the classes of fatty acids on the triacylglycerol backbone indicated a saturated and unsaturated fatty acid relationship similar in the three-triacylglycerol positions. All tocopherol isomers were present, with a total content of 2364.1 mg·kg−1. α-tocopherol constitutes 48% of the total tocopherol content, followed by γ- tocopherol (45%. Total phenolic (107.0 mg gallic acid equivalent·g−1 oil and β-carotene (781.6 mg·kg−1 were particularly high in this oil. The highest antioxidant activity against the free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH was obtained at an oil concentration of 50 mg·mL−1 (73.15%. The antioxidant activity evaluated by the Oxygen Radical Absorbance Capacity (ORAC was 95.3 μmol Trolox equivalent·g−1 oil. These results serve to present Buriti oil as an Amazonian resource for cosmetic, food and pharmaceuticals purposes.El aceite de Buriti es un ejemplo de aceite de palma amazónica de gran importancia económica. La población local utiliza este aceite para la prevención y el tratamiento de diferentes enfermedades; sin embargo, hay pocos estudios científicos que evalúen sus propiedades. En este estudio, se determinaron las propiedades antioxidantes del aceite de Buriti. El ácido graso predominante fue el oleico (65,6 % y las principales clases de triglicéridos fueron tri-insaturadas (50,0 % y Di-insaturados-mono-saturada (39,3 %. La distribución posicional de las

  1. Alluvial deposits and plant distribution in an Amazonian lowland megafan

    Science.gov (United States)

    Zani, H.; Rossetti, D.; Cremon; Cohen, M.; Pessenda, L. C.

    2012-12-01

    A large volume of sandy alluvial deposits (> 1000 km2) characterizes a flat wetland in northern Amazonia. These have been recently described as the sedimentary record of a megafan system, which have a distinct triangular shape produced by highly migratory distributary rivers. The vegetation map suggests that this megafan is dominated by open vegetation in sharp contact with the surround rainforest. Understanding the relationship between geomorphological processes and vegetation distribution is crucial to decipher and conserve the biodiversity in this Amazonian ecosystem. In this study we interpret plant dynamics over time, and investigate its potential control by sedimentary processes during landscape evolution. The study area is located in the Viruá National Park. Two field campaigns were undertaken in the dry seasons of 2010 and 2011 and the sampling sites were selected by combining accessibility and representativeness. Vegetation contrasts were recorded along a transect in the medial section of the Viruá megafan. Due to the absence of outcrops, samples were extracted using a core device, which allowed sampling up to a depth of 7.5 m. All cores were opened and described in the field, with 5 cm3 samples collected at 20 cm intervals. The δ13C of organic matter was used as a proxy to distinguish between C3 and C4 plant communities. The chronology was established based on radiocarbon dating. The results suggest that the cores from forested areas show the most depleted values of δ13C, ranging from -32.16 to -27.28‰. The δ13C curve in these areas displays typical C3 land plant values for the entire record, which covers most of the Holocene. This finding indicates that either the vegetation remained stable over time or the sites were dominated by aquatic environments with freshwater plants before forest establishment. The cores from the open vegetation areas show a progressive upward enrichment in δ13C values, which range from -28.50 to -19.59‰. This trend is

  2. Thresholds of species loss in Amazonian deforestation frontier landscapes.

    Science.gov (United States)

    Ochoa-Quintero, Jose Manuel; Gardner, Toby A; Rosa, Isabel; Ferraz, Silvio Frosini de Barros; Sutherland, William J

    2015-04-01

    In the Brazilian Amazon, private land accounts for the majority of remaining native vegetation. Understanding how land-use change affects the composition and distribution of biodiversity in farmlands is critical for improving conservation strategies in the face of rapid agricultural expansion. Working across an area exceeding 3 million ha in the southwestern state of Rondônia, we assessed how the extent and configuration of remnant forest in replicate 10,000-ha landscapes has affected the occurrence of a suite of Amazonian mammals and birds. In each of 31 landscapes, we used field sampling and semistructured interviews with landowners to determine the presence of 28 large and medium sized mammals and birds, as well as a further 7 understory birds. We then combined results of field surveys and interviews with a probabilistic model of deforestation. We found strong evidence for a threshold response of sampled biodiversity to landscape level forest cover; landscapes with deforested landscapes many species are susceptible to extirpation following relatively small additional reductions in forest area. In the model of deforestation by 2030 the number of 10,000-ha landscapes under a conservative threshold of 43% forest cover almost doubled, such that only 22% of landscapes would likely to be able to sustain at least 75% of the 35 focal species we sampled. Brazilian law requires rural property owners in the Amazon to retain 80% forest cover, although this is rarely achieved. Prioritizing efforts to ensure that entire landscapes, rather than individual farms, retain at least 50% forest cover may help safeguard native biodiversity in private forest reserves in the Amazon. © 2015 Society for Conservation Biology.

  3. Are tortoises important seed dispersers in Amazonian forests?

    Science.gov (United States)

    Jerozolimski, Adriano; Ribeiro, Maria Beatriz N; Martins, Marcio

    2009-09-01

    According to most studies on seed dispersal in tropical forests, mammals and birds are considered the main dispersal agents and the role played by other animal groups remains poorly explored. We investigate qualitative and quantitative components of the role played by the tortoise Chelonoidis denticulata in seed dispersal in southeastern Amazon, and the influence of seasonal variation in tortoise movement patterns on resulting seed shadows. Seed shadows produced by this tortoise were estimated by combining information on seed passage times through their digestive tract, which varied from 3 to 17 days, with a robust dataset on movements obtained from 18 adult C. denticulata monitored with radio transmitters and spoon-and-line tracking devices. A total of 4,206 seeds were found in 94 collected feces, belonging to 50 seed morphotypes of, at least, 25 plant genera. Very low rates of damage to the external structure of the ingested seeds were observed. Additionally, results of germination trials suggested that passage of seeds through C. denticulata's digestive tract does not seem to negatively affect seed germination. The estimated seed shadows are likely to contribute significantly to the dispersal of seeds away from parent plants. During the dry season seeds were dispersed, on average, 174.1 m away from the location of fruit ingestion; during the rainy season, this mean dispersal distance increased to 276.7 m. Our results suggest that C. denticulata plays an important role in seed dispersal in Amazonian forests and highlight the influence of seasonal changes in movements on the resulting seed shadows.

  4. Environmental characteristics drive variation in Amazonian understorey bird assemblages.

    Science.gov (United States)

    Menger, Juliana; Magnusson, William E; Anderson, Marti J; Schlegel, Martin; Pe'er, Guy; Henle, Klaus

    2017-01-01

    Tropical bird assemblages display patterns of high alpha and beta diversity and, as tropical birds exhibit strong habitat specificity, their spatial distributions are generally assumed to be driven primarily by environmental heterogeneity and interspecific interactions. However, spatial distributions of some Amazonian forest birds are also often restricted by large rivers and other large-scale topographic features, suggesting that dispersal limitation may also play a role in driving species' turnover. In this study, we evaluated the effects of environmental characteristics, topographic and spatial variables on variation in local assemblage structure and diversity of birds in an old-growth forest in central Amazonia. Birds were mist-netted in 72 plots distributed systematically across a 10,000 ha reserve in each of three years. Alpha diversity remained stable through time, but species composition changed. Spatial variation in bird-assemblage structure was significantly related to environmental and topographic variables but not strongly related to spatial variables. At a broad scale, we found bird assemblages to be significantly distinct between two watersheds that are divided by a central ridgeline. We did not detect an effect of the ridgeline per se in driving these patterns, indicating that most birds are able to fly across it, and that differences in assemblage structure between watersheds may be due to unmeasured environmental variables or unique combinations of measured variables. Our study indicates that complex geography and landscape features can act together with environmental variables to drive changes in the diversity and composition of tropical bird assemblages at local scales, but highlights that we still know very little about what makes different parts of tropical forest suitable for different species.

  5. Slow growth rates of Amazonian trees: Consequences for carbon cycling

    Science.gov (United States)

    Vieira, Simone; Trumbore, Susan; Camargo, Plinio B.; Selhorst, Diogo; Chambers, Jeffrey Q.; Higuchi, Niro; Martinelli, Luiz Antonio

    2005-01-01

    Quantifying age structure and tree growth rate of Amazonian forests is essential for understanding their role in the carbon cycle. Here, we use radiocarbon dating and direct measurement of diameter increment to document unexpectedly slow growth rates for trees from three locations spanning the Brazilian Amazon basin. Central Amazon trees, averaging only ≈1mm/year diameter increment, grow half as fast as those from areas with more seasonal rainfall to the east and west. Slow growth rates mean that trees can attain great ages; across our sites we estimate 17-50% of trees with diameter >10 cm have ages exceeding 300 years. Whereas a few emergent trees that make up a large portion of the biomass grow faster, small trees that are more abundant grow slowly and attain ages of hundreds of years. The mean age of carbon in living trees (60-110 years) is within the range of or slightly longer than the mean residence time calculated from C inventory divided by annual C allocation to wood growth (40-100 years). Faster C turnover is observed in stands with overall higher rates of diameter increment and a larger fraction of the biomass in large, fast-growing trees. As a consequence, forests can recover biomass relatively quickly after disturbance, whereas recovering species composition may take many centuries. Carbon cycle models that apply a single turnover time for carbon in forest biomass do not account for variations in life strategy and therefore may overestimate the carbon sequestration potential of Amazon forests. PMID:16339903

  6. Environmental characteristics drive variation in Amazonian understorey bird assemblages

    Science.gov (United States)

    Magnusson, William E.; Anderson, Marti J.; Schlegel, Martin; Pe’er, Guy; Henle, Klaus

    2017-01-01

    Tropical bird assemblages display patterns of high alpha and beta diversity and, as tropical birds exhibit strong habitat specificity, their spatial distributions are generally assumed to be driven primarily by environmental heterogeneity and interspecific interactions. However, spatial distributions of some Amazonian forest birds are also often restricted by large rivers and other large-scale topographic features, suggesting that dispersal limitation may also play a role in driving species’ turnover. In this study, we evaluated the effects of environmental characteristics, topographic and spatial variables on variation in local assemblage structure and diversity of birds in an old-growth forest in central Amazonia. Birds were mist-netted in 72 plots distributed systematically across a 10,000 ha reserve in each of three years. Alpha diversity remained stable through time, but species composition changed. Spatial variation in bird-assemblage structure was significantly related to environmental and topographic variables but not strongly related to spatial variables. At a broad scale, we found bird assemblages to be significantly distinct between two watersheds that are divided by a central ridgeline. We did not detect an effect of the ridgeline per se in driving these patterns, indicating that most birds are able to fly across it, and that differences in assemblage structure between watersheds may be due to unmeasured environmental variables or unique combinations of measured variables. Our study indicates that complex geography and landscape features can act together with environmental variables to drive changes in the diversity and composition of tropical bird assemblages at local scales, but highlights that we still know very little about what makes different parts of tropical forest suitable for different species. PMID:28225774

  7. Common vampire bat attacks on humans in a village of the Amazon region of Brazil

    Directory of Open Access Journals (Sweden)

    Schneider Maria Cristina

    2001-01-01

    Full Text Available Many people in Amazonian communities have reported bat bites in the last decade. Bites by vampire bats can potentially transmit rabies to humans. The objective of this study was to analyze factors associated with bat biting in one of these communities. A cross-sectional survey was conducted in a village of gold miners in the Amazonian region of Brazil (160 inhabitants. Bats were captured near people's houses and sent to a lab. Of 129 people interviewed, 41% had been attacked by a bat at least once, with 92% of the bites located on the lower limbs. A logistic regression found that adults were bitten around four times more often than children (OR = 3.75, CI 95%: 1.46-9.62, p = 0.036. Males were bitten more frequently than females (OR = 2.08, CI 95%: 0.90-4.76, p = 0.067. Nine Desmodus rotundus and three frugivorous bats were captured and tested negative for rabies. The study suggests that, in an area of gold miners, common vampire bats are more likely to attack adults and males. The control strategy for human rabies developed in this region should therefore place special emphasis on adult males. There should also be more research on how the search for gold in the Amazonian region places people and the environment at risk.

  8. A new species of Scinax Wagler, 1830 (Anura: Hylidae from the middle Amazon river basin, Brazil

    Directory of Open Access Journals (Sweden)

    Marcelo José Sturaro

    2014-01-01

    Full Text Available A new species of the hylid genus Scinax is described and illustrated. The new taxon was found in the Amazonian rainforest of northern Brazil, municipalities of Maués and Careiro da Várzea, state of Amazonas. The new species is characterized by its moderate size (male mean snout-vent length 36.3mm; body robust; large, orange, black-bordered axillary and inguinal spots; and bilobate vocal sac. This new species was found in primary and secondary forest on branches of shrubs or trees in, or next to, permanent ponds and flooded areas.

  9. Recent (Late Amazonian) enhanced backweathering rates on Mars : Paracratering evidence from gully alcoves

    NARCIS (Netherlands)

    De Haas, Tjalling; Conway, Susan J.; Krautblatter, Michael

    2015-01-01

    Mars is believed to have been exposed to low planet-wide weathering and denudation since the Noachian. However, the widespread occurrence of alcoves at the rim of pristine impact craters suggests locally enhanced recent backweathering rates. Here we derive Late Amazonian backweathering rates from th

  10. Amazonian-aged fluvial system and associated ice-related features in Terra Cimmeria, Mars

    NARCIS (Netherlands)

    Adeli, Solmaz; Hauber, Ernst; Kleinhans, Maarten; Le Deit, Laetitia; Platz, Thomas; Fawdon, Peter; Jaumann, Ralf

    2016-01-01

    The Martian climate throughout the Amazonian is widely believed to have been cold and hyper-arid, very similar to the current conditions. However, ubiquitous evidence of aqueous and glacial activity has been recently reported, including channels that can be tens to hundreds of kilometres long, alluv

  11. Soil Fraction and Black Carbon Particles of Amazonian Dark Earth Harbor Different Fungal Abundance and Diversity

    NARCIS (Netherlands)

    Reis Lucheta, Adriano; Souza Cannavan, F.S.; Tsai, S.M.; Kuramae, E.E.

    2017-01-01

    Amazonian Dark Earth (ADE) is a highly fertile soil of anthropogenic origin characterized by higher amount of charred black carbon (BC). ADE is considered a fertility model, however knowledge about the fungal community structure and diversity inhabiting ADE and BC is scarce. Fungal community

  12. Effects of Amazonian Dark Earths on growth and leaf nutrient balance of tropical tree seedlings

    NARCIS (Netherlands)

    Quintero Vallejo, Estela; Pena Claros, M.; Bongers, F.; Toledo, M.; Poorter, L.

    2015-01-01

    Background and aims: Amazonian Dark Earths (ADE) are ancient anthropogenic soils distributed in the Amazon basin. They are characterized by high nutrients such as phosphorus, calcium, potassium and nitrogen. We studied the effect of ADE on growth, morphology and physiology of 17 tree species from a

  13. Effects of reduced-impact logging and forest physiognomy on bat populations of lowland Amazonian forest.

    Science.gov (United States)

    Steven J. Presley; Michael R. Willig; Wunderle Jr. Joseph M.; Luis Nélio. Saldanha

    2008-01-01

    1.As human population size increases, demand for natural resources will increase. Logging pressure related to increasing demands continues to threaten remote areas of Amazonian forest. A harvest protocol is required to provide renewable timber resources that meet consumer needs while minimizing negative effects on biodiversity and ecosystem services. Reduced-impact...

  14. Evolutionary patterns of range size, abundance and species richness in Amazonian angiosperm trees

    Science.gov (United States)

    Chave, Jérôme

    2016-01-01

    Amazonian tree species vary enormously in their total abundance and range size, while Amazonian tree genera vary greatly in species richness. The drivers of this variation are not well understood. Here, we construct a phylogenetic hypothesis that represents half of Amazonian tree genera in order to contribute to explaining the variation. We find several clear, broad-scale patterns. Firstly, there is significant phylogenetic signal for all three characteristics; closely related genera tend to have similar numbers of species and similar mean range size and abundance. Additionally, the species richness of genera shows a significant, negative relationship with the mean range size and abundance of their constituent species. Our results suggest that phylogenetically correlated intrinsic factors, namely traits of the genera themselves, shape among lineage variation in range size, abundance and species richness. We postulate that tree stature may be one particularly relevant trait. However, other traits may also be relevant, and our study reinforces the need for ambitious compilations of trait data for Amazonian trees. In the meantime, our study shows how large-scale phylogenies can help to elucidate, and contribute to explaining, macroecological and macroevolutionary patterns in hyperdiverse, yet poorly understood regions like the Amazon Basin. PMID:27651991

  15. Widespread loess-like deposit in the Martian northern lowlands identifies Middle Amazonian climate change

    Science.gov (United States)

    Skinner, James A.; Tanaka, Kenneth L.; Thomas Platz,

    2014-01-01

    Consistently mappable units critical to distinguishing the style and interplay of geologic processes through time are sparse in the Martian lowlands. This study identifies a previously unmapped Middle Amazonian (ca. 1 Ga) unit (Middle Amazonian lowland unit, mAl) that postdates the Late Hesperian and Early Amazonian lowland plains by >2 b.y. The unit is regionally defined by subtle marginal scarps and slopes, has a mean thickness of 32 m, and extends >3.1 × 106 km2 between lat 35°N and 80°N. Pedestal-type craterforms and nested, arcuate ridges (thumbprint terrain) tend to occur adjacent to unit mAl outcrops, suggesting that current outcrops are vestiges of a more extensive deposit that previously covered ∼16 × 106 km2. Exposed layers, surface pits, and the draping of subjacent landforms allude to a sedimentary origin, perhaps as a loess-like deposit emplaced rhythmically through atmospheric fallout. We propose that unit mAl accumulated coevally with, and at the expense of, the erosion of the north polar basal units, identifying a major episode of Middle Amazonian climate-driven sedimentation in the lowlands. This work links ancient sedimentary processes to climate change that occurred well before those implied by current orbital and spin axis models.

  16. Morphology, morphometry and ultrastructure of the Amazonian manatee (Sirenia: Trichechidae spermatozoa

    Directory of Open Access Journals (Sweden)

    Rodrigo S. Amaral

    2010-01-01

    Full Text Available This study describes the morphological, morphometric and ultrastructural characteristics of the Amazonian manatee Trichechus inunguis (Natterer, 1883 spermatozoon. The spermatozoa were obtained from a urine sample of an adult T. inunguis kept in captivity. The spermatozoa were analyzed by light and transmission electron microscopy. The head of Amazonian manatee spermatozoa had a flat oval shape and a well distinguishable midpiece. The mean dimensions of the spermatozoa were: head length, 7.49 ± 0.24 µm; head width, 3.53 ± 0.19 µm; head thickness, 1.61 ± 0.13 µm; midpiece length, 11.36 ± 0.34 µm; flagellum length, 40.91 ± 1.94 µm; total tail length, 52.16 ± 1.06 µm; total spermatozoon length, 60.08 ± 1.40 µm. The Amazonian manatee spermatozoa were similar in shape to other sirenian spermatozoa; however, presenting a different size. This study describes, for the first time, the morphometric and ultrastructural characteristics of the Amazonian manatee spermatozoa, and also demonstrates the possible use of spermatozoa retrieved from urine samples for biological studies.

  17. Recent (Late Amazonian) enhanced backweathering rates on Mars : Paracratering evidence from gully alcoves

    NARCIS (Netherlands)

    De Haas, Tjalling; Conway, Susan J.; Krautblatter, Michael

    2015-01-01

    Mars is believed to have been exposed to low planet-wide weathering and denudation since the Noachian. However, the widespread occurrence of alcoves at the rim of pristine impact craters suggests locally enhanced recent backweathering rates. Here we derive Late Amazonian backweathering rates from

  18. The role of Amazonian anthropogenic soils in shifting cultivation: learning from farmers’ rationales

    NARCIS (Netherlands)

    Braga Junqueira, A.; Almekinders, C.J.M.; Stomph, T.J.; Clement, C.R.; Struik, P.C.

    2016-01-01

    We evaluated farmers’ rationales to understand their decision making in relation to the use of fertile anthropogenic soils, i.e., Amazonian dark earths (ADE), and for dealing with changes in shifting cultivation in Central Amazonia. We analyzed qualitative information from 196 interviews with farmer

  19. Legacies of Amazonian dark earths on forest composition, structure and dynamics

    NARCIS (Netherlands)

    Quintero Vallejo, E.M.

    2015-01-01

    Summary

    Amazonian forest is seen as the archetype of pristine forests, untouched by humans, but this romantic view is far from reality. In recent years, there is increasing evidence of long and extensive landscape modification by humans. Processes of permanent inhabitation,

  20. Recent (Late Amazonian) enhanced backweathering rates on Mars : Paracratering evidence from gully alcoves

    NARCIS (Netherlands)

    De Haas, Tjalling; Conway, Susan J.; Krautblatter, Michael

    2015-01-01

    Mars is believed to have been exposed to low planet-wide weathering and denudation since the Noachian. However, the widespread occurrence of alcoves at the rim of pristine impact craters suggests locally enhanced recent backweathering rates. Here we derive Late Amazonian backweathering rates from th

  1. The Perceptions of Knowledge and Learning of Amazonian Indigenous Teacher Education Students

    Science.gov (United States)

    Veintie, Tuija; Holm, Gunilla

    2010-01-01

    This study focuses on the perceptions of knowledge and learning by indigenous students in an intercultural bilingual teacher education programme in Amazonian Ecuador. The study framed within postcolonial and critical theory attempts to create a space for the indigenous students to speak about their own views through the use of photography and…

  2. Interpreting participatory Fuzzy Cognitive Maps as complex networks in the social-ecological systems of the Amazonian forests

    Science.gov (United States)

    Varela, Consuelo; Tarquis, Ana M.; Blanco-Gutiérrez, Irene; Estebe, Paloma; Toledo, Marisol; Martorano, Lucieta

    2015-04-01

    Social-ecological systems are linked complex systems that represent interconnected human and biophysical processes evolving and adapting across temporal and spatial scales. In the real world, social-ecological systems pose substantial challenges for modeling. In this regard, Fuzzy Cognitive Maps (FCMs) have proven to be a useful method for capturing the functioning of this type of systems. FCMs are a semi-quantitative type of cognitive map that represent a system composed of relevant factors and weighted links showing the strength and direction of cause-effects relationships among factors. Therefore, FCMs can be interpreted as complex system structures or complex networks. In this sense, recent research has applied complex network concepts for the analysis of FCMs that represent social-ecological systems. Key to FCM the tool is its potential to allow feedback loops and to include stakeholder knowledge in the construction of the tool. Also, previous research has demonstrated their potential to represent system dynamics and simulate the effects of changes in the system, such as policy interventions. For illustrating this analysis, we have developed a series of participatory FCM for the study of the ecological and human systems related to biodiversity conservation in two case studies of the Amazonian region, the Bolivia lowlands of Guarayos and the Brazil Tapajos National forest. The research is carried out in the context of the EU project ROBIN1 and it is based on the development of a series of stakeholder workshops to analyze the current state of the socio-ecological environment in the Amazonian forest, reflecting conflicts and challenges for biodiversity conservation and human development. Stakeholders included all relevant actors in the local case studies, namely farmers, environmental groups, producer organizations, local and provincial authorities and scientists. In both case studies we illustrate the use of complex networks concepts, such as the adjacency

  3. [Myths concerning malarial transmission among Amazonian Indians and their relation with 2 types of transmission encountered in the Amazonian forest].

    Science.gov (United States)

    Molez, J F

    1999-01-01

    Among the Indians Desana's (Tukano amerindians) in the Upper Rio Negro, the interseasonal variation of the malarial fevers were associated with two myths (localised in two distinguishable places). One myth associates the malarial with the rivers which contain "malaria pots". Conception based on an observation of localised water collection in the banks and the rocky rapids ("banks and rocky's fever"). The transmission and the anophelian density present variation between the seasons in relation to the river's level. Another myth associates malarial fevers in the forest, with the song of a frog ("fever's frog") and the flowering and fructification of a tree (Poaqueira sericea Thul.). There is in South America a particular type of forest malaria, known as "Bromelia malaria" and denounced in human and/or simian transmission. This forest malaria is transmitted by the a sub-genus anopheles (Kerteszia) which larval breeding are areal in the canopy. The breeding places are found in the forest in the epiphyte bromeliads. To understand this type of transmission, we must take reference to the previous endomological data at the Upper Oyapock Wayâpi (Tupi amerindians). This Bromelia malaria could fluctuated according larval density variation, related to washing of epiphytes (end of the rainy season) or to their flowering (end of the dry season). The "fever's frog" myth collected at the Desana's in the Upper Rio Negro can be related to the existence of Bromelia malaria in this amazonian habitat. These myths showed the perfect adaptation of the amerindians to their environment and their complete knowledge of the neotropical forest.

  4. Prevalência de cárie dental em uma população de escolares da região amazônica Prevalence of dental caries in a school population of the amazonian region

    Directory of Open Access Journals (Sweden)

    Antonio David Corrêa Normando

    1990-08-01

    Full Text Available Considerando-se a ausência de dados sobre a prevalência de cárie dental em uma população tipicamente amazônida, foi feito um levantamento epidemiológico em 103 escolares na região da Ilha de Sirituba, no Município de Abaetetuba, Estado do Pará, Brasil. O CPOD médio encontrado foi de 6,5 e o ceo de 5,4. Apesar da primitividade do local, o alto índice de cárie pode estar relacionado a diversos fatores, dentre os quais deve ser incluída a influência urbana na alimentação, principalmente pelo açúcar, criando novos hábitos alimentares que alteraram fundamentalmente a dieta da região.In view of the lack of data as to the prevalence of dental caries among typical amazonian populations, the authors carried out an epidemiological study of 103 schoolchildren from Sirituba Island, Abaetetuba, Pará, Brazil. The mean values found for DMFT and deft were 6.5 and 5.4 respectively. Although the region is very primitive, this high prevalence may be linked to several factors, among which is the urban influence, mainly through the use of sugar, on food habits in such a way as fundamentally to alter the diet of the amazonian population.

  5. The sequence stratigraphy of the Campo Mourao (upper part) and Taciba Formations, Itarare Group, Eastern part of the Parana Basin, Brazil; Estratigrafia de sequencias das formacoes Campo Mourao (parte superior) e Taciba, Grupo Itarare, Leste da Bacia do Parana

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Joel Carneiro de [UNESP, Rio Claro, SP (Brazil). Inst. de Geociencias e Ciencias Exatas. E-mail: jocastro@caviar.igce.unesp.br

    1999-06-01

    The chronostratigraphic framework of the Campo Mourao (upper part) and Taciba formations, Itarare Group was investigated through a subsurface study in the eastern flank of the Parana Basin. A total of five depositional sequences were recognized, each represented by an upward increase in the argillaceous content (sandstone to diamictite to shale). The upper part of basal sequence 1 is formed by a thick diamictite by the Lontras Shale; these glaciomarine and marine systems may constitute the transgressive tract of the sequence and represent the top of Campo Mourao Formation/cycle. The Lontras Shale (or Member) is not restricted to the Santa Catarina State; instead it is recognized throughout the eastern flank of the basin. The sequence 2 is represented in the basal portion by the sandstones of Rio Segredo (base of Taciba Formation/cycle). The next sequences are similar to the previous one, including some particular patterns: as the basal sandstones form clastic wedges, the sequence may be represented exclusively by diamictities. The clastic wedges of sequences 2 and 4 were applied from east and northeast; the western margin also contributed as source of coarse clastics. Sequences 4 and 5 were studied in detail, since they were reached by several shallow wells near the outcrop belt. the sequence 4 clearly displays facies change from marine in the south (Passinho Shale) to delta front in center-south, and to coal-bearing delta plain in the north. The occurrence of sequence 5 is restricted to southern Parana and northern Santa Catarina; it presents deltaic sandstone deposits intercalated with marine shales/sandstones and glaciomarine diamictites. Despite some transitional characteristics shown by the upper part of Itarare Group (sequences 4 and 5), it is noteworthy the unconformable of the Group with the overlying, post-glacial Triunfo Member of Rio Bonito Formation. (author)

  6. Impacts of selective logging on inbreeding and gene flow in two Amazonian timber species with contrasting ecological and reproductive characteristics.

    Science.gov (United States)

    Vinson, C C; Kanashiro, M; Harris, S A; Boshier, D H

    2015-01-01

    Selective logging in Brazil allows for the removal of up to 90% of trees above 50 cm diameter of a given timber species, independent of a species' life history characteristics or how quickly it will recover. The genetic and demographic effects of selective logging on two Amazonian timber species (Dipteryx odorata Leguminosae, Jacaranda copaia Bignoniaceae) with contrasting ecological and reproductive characteristics were assessed in the same forest. Genetic diversity and gene flow were characterized by genotyping adults and seed sampled before and after logging, using hypervariable microsatellite markers. Overall, there were no short-term genetic impacts on the J. copaia population, with commercial application of current Brazilian forest management regulations. In contrast, for D. Odorata, selective logging showed a range of genetic impacts, with a 10% loss of alleles, and reductions in siring by pollen from trees within the 546-ha study area (23-11%) and in the number of pollen donors per progeny array (2.8-1.6), illustrating the importance of the surrounding landscape. Asynchrony in flowering between D. odorata trees led to trees with no breeding partners, which could limit the species reproduction and regeneration under current regulations. The results are summarized with other published studies from the same site and the implications for forest management discussed. The different types and levels of impacts associated with each species support the idea that ecological and genetic information by species, ecological guild or reproductive group is essential in helping to derive sustainable logging guidelines for tropical forests.

  7. Implication of Forest-Savanna Dynamics on Biomass and Carbon Stock: Effectiveness of an Amazonian Ecological Station

    Science.gov (United States)

    Couto-Santos, F. R.; Luizao, F. J.

    2014-12-01

    The forests-savanna advancement/retraction process seems to play an important role in the global carbon cycle and in the climate-vegetation balance maintenance in the Amazon. To contribute with long term carbon dynamics and assess effectiveness of a protected area in reduce carbon emissions in Brazilian Amazon transitional areas, variations in forest-savanna mosaics biomass and carbon stock within Maraca Ecological Station (MES), Roraima/Brazil, and its outskirts non-protected areas were compared. Composite surface soil samples and indirect methods based on regression models were used to estimate aboveground tree biomass accumulation and assess vegetation and soil carbon stock along eleven 0.6 ha transects perpendicular to the forest-savanna limits. Aboveground biomass and carbon accumulation were influenced by vegetation structure, showing higher values within protected area, with great contribution of trees above 40 cm in diameter. In the savanna environments of protected areas, a higher tree density and carbon stock up to 30 m from the border confirmed a forest encroachment. This pointed that MES acts as carbon sink, even under variations in soil fertility gradient, with a potential increase of the total carbon stock from 9 to 150 Mg C ha-1. Under 20 years of fire and disturbance management, the results indicated the effectiveness of this protected area to reduce carbon emissions and mitigate greenhouse and climate change effects in a forest-savanna transitional area in Brazilian Northern Amazon. The contribution of this study in understanding rates and reasons for biomass and carbon variation, under different management strategies, should be considered the first approximation to assist policies of reducing emissions from deforestation and forest degradation (REDD) from underresearched Amazonian ecotone; despite further efforts in this direction are still needed. FINANCIAL SUPPORT: Boticário Group Foundation (Fundação Grupo Boticário); National Council for

  8. Heterogeneous movement of insectivorous Amazonian birds through primary and secondary forest: A case study using multistate models with radiotelemetry data

    Science.gov (United States)

    Hines, James; Powell, Luke L.; Wolfe, Jared D.; Johnson, Erik l.; Nichols, James D.; Stouffer, Phillip C.

    2015-01-01

    Given rates of deforestation, disturbance, and secondary forest accumulation in tropical rainforests, there is a great need to quantify habitat use and movement among different habitats. This need is particularly pronounced for animals most sensitive to disturbance, such as insectivorous understory birds. Here we use multistate capture–recapture models with radiotelemetry data to determine the successional stage at which within-day movement probabilities of Amazonian birds in secondary forest are similar to those in primary forest. We radio-tracked three common understory insectivore species in primary and secondary forest at the Biological Dynamics of Forest Fragments project near Manaus, Brazil: two woodcreepers, Glyphorynchus spirurus (n = 19) andXiphorhynchus pardalotus (n = 18), and the terrestrial antthrush Formicarius colma(n = 19). Forest age was a strong predictor of fidelity to a given habitat. All three species showed greater fidelity to primary forest than to 8–14-year-old secondary forest, indicating the latter’s relatively poor quality. The two woodcreeper species used 12–18-year-old secondary forest in a manner comparable to continuous forest, but F. colmaavoided moving even to 27–31-year-old secondary forest—the oldest at our site. Our results suggest that managers concerned with less sensitive species can assume that forest reserves connected by 12–18-year-old secondary forest corridors are effectively connected. On the other hand, >30 years are required after land abandonment before secondary forest serves as a primary forest-like conduit for movement by F. colma; more sensitive terrestrial insectivores may take longer still.

  9. Henneguya torpedo sp. nov. (Myxozoa), a parasite from the nervous system of the Amazonian teleost Brachyhypopomus pinnicaudatus (Hypopomidae).

    Science.gov (United States)

    Azevedo, Carlos; Casal, Graça; Matos, Patrícia; Alves, Angela; Matos, Edilson

    2011-02-22

    A new species of Myxosporea, Henneguya torpedo sp. nov., is described from the brain and spinal cord of the Amazonian teleostean fish Brachyhypopomus pinnicaudatus collected from the Peixe Boi River, State of Park, Brazil. The spores were surrounded by a thick hyaline sheath that is homogeneous and electron translucent and consists of 2 layers of different densities. The total spore length is 48.62 +/- 0.51 microm (mean +/- SE), the ellipsoidal spore body length is 28.53 +/- 0.36 microm, the body width is 7.25 +/- 0.31 microm and the body thickness is 3.06 +/- 0.26 microm. Each of the 2 equal-sized valves presented a tapering tail (19.64 +/- 0.44 microm in length). The 2 equal-sized thin and smooth valves surrounded 2 equal-sized and elongated ellipsoidal polar capsules (6.41 +/- 0.26 x 1.84 +/- 0.19 microm) that contained 5 to 6 (rarely 7) polar filament coils. The binucleated sporoplasm contained numerous spherical sporoplasmosomes (-260 x -280 nm) with a laterally eccentric-dense structure containing a half-crescent section. The sporoplasmosomes are surrounded by a hyaline homogenous sheath. Based on the data obtained by light and electron microscopy and on the host specificity, the spores differed from the previously described Henneguya spp., mainly in the presence of a sheath surrounding the spores, the spore shape and size and the number and arrangement of the polar filament coils. Therefore, from this description we propose the establishment of a new species, which we have named Henneguya torpedo sp. nov.

  10. Understanding moisture recycling for atmospheric river management in Amazonian communities

    Science.gov (United States)

    Weng, Wei; Luedeke, Matthias; Zemp, Delphine-Clara; Lakes, Tobia; Pradhan, Prajal; Kropp, Juergen

    2017-04-01

    The invisible atmospheric transports of moisture have recently attracted more research efforts into understanding their structures, processes involved and their function as an ecosystem service. Current attention has been focused on larger scale analysis such as studying global or continental level moisture recycling. Here we applied a water balance model to backtrack the flying river that sustains two local communities in the Colombian and Peruvian Amazon where vulnerable communities rely highly on the rainfall for agricultural practices. By utilising global precipitation (TRMM Multisatillite Precipitation Analysis; TMPA) and evapotranspiration products (Moderate Resolution Imaging Spectroradiometer MODIS, MOD16ET) as input data in the present modelling experiments to compensate the sparse ground observation data in these regions, the moisture recycling process targeting the two amazonian communities which has not yet been explored quantitatively has been shown. The TMPA was selected because of its proved comparativeness with observation data in its precipitation estimations over Amazon regions while the MOD16ET data was chosen for being validated by previous studies in the Amazon basin and for reported good performance. In average, 45.5 % of the precipitation occurring to Caquetá region in Colombia is of terrestrial origin from the South American continent while 48.2% of the total rainfall received by Peruvian Yurimaguas is also from the South American land sources. The spatial distribution of the precipitationsheds (defined previously as the upwind contribution of evapotranspiration to a specific location's precipitation) shows transboundary and transnational shares in the moisture contributors of the precipitation for both regions. An interesting reversed upstream-downstream roles can be observed when the upstream regions in traditional watershed thinking become downstream areas considering precipitationsheds and flying rivers. Strong seasonal variations are

  11. Napoleon Bonaparte and the fate of an Amazonian rat: new data on the taxonomy of Mesomys hispidus (Rodentia: Echimyidae).

    Science.gov (United States)

    Orlando, Ludovic; Mauffrey, Jean-François; Cuisin, Jacques; Patton, James L; Hänni, Catherine; Catzeflis, François

    2003-04-01

    The spiny rat Mesomys hispidus is one of many South American rodents that lack adequate taxonomic definition. The few sampled populations of this broadly distributed trans-Amazonian arboreal rat have come from widely separated regions and are typically highly divergent. The holotype was described in 1817 by A.-G. Desmarest, after Napoleon's army brought it to Paris following the plunder of Lisbon in 1808; however, the locality of origin has remained unknown. Here we examine the taxonomic status of this species by direct comparison of 50 extant individuals with the holotype at the morphometric and genetic levels, the latter based on 331 bp of the mitochondrial cytochrome b gene retrieved from a small skin fragment of the holotype with ancient DNA technology. Extensive sequence divergence is present among samples of M. hispidus collected from throughout its range, from French Guiana across Amazonia to Bolivia and Peru, with at least seven mitochondrial clades recognized (average divergence of 7.7% Kimura 2-parameter distance). Sequence from the holotype is, however, only weakly divergent from those of recent samples from French Guiana. Moreover, the holotype clusters with greater that 99% posterior probability with samples from this part of Amazonia in a discriminant analysis based on 22 cranial and dental measurements. Thus, we suggest that the holotype was originally obtained in eastern Amazonia north of the Amazon River, most likely in the Brazilian state of Amapá. Despite the high level of sequence diversity and marked morphological differences in size across the range of M. hispidus, we continue to regard this assemblage as a single species until additional samples and analyses suggest otherwise.

  12. Sediment source, turbidity maximum, and implications for mud exchange between channel and mangroves in an Amazonian estuary

    Science.gov (United States)

    Asp, Nils Edvin; Gomes, Vando José Costa; Ogston, Andrea; Borges, José Carlos Corrêa; Nittrouer, Charles Albert

    2016-02-01

    The tide-dominated eastern sector of the Brazilian Amazonian coast includes large mangrove areas and several estuaries, including the estuary associated with the Urumajó River. There, the dynamics of suspended sediments and delivery mechanisms for mud to the tidal flats and mangroves are complex and were investigated in this study. Four longitudinal measuring campaigns were carried out, encompassing spring/neap tides and dry/rainy seasons. During spring tides, water levels were measured simultaneously at 5 points along the estuary. Currents, salinity, and suspended sediment concentrations (SSCs) were measured over the tidal cycle in a cross section at the middle sector of the estuary. Results show a marked turbidity maximum zone (TMZ) during the rainy season, with a 4-km upstream displacement from neap to spring tide. During dry season, the TMZ was conspicuous only during neap tide and dislocated about 5 km upstream and was substantially less apparent in comparison to that observed during rainy season. The results show that mud is being concentrated in the channel associated with the TMZ especially during the rainy season. At this time, a substantial amount of the mud is washed out from mangroves to the estuarine channel and hydrodynamic/salinity conditions for TMZ formation are optimal. As expected, transport to the mangrove flats is most effective during spring tide and substantially reduced at neap tide, when mangroves are not being flooded. During the dry season, mud is resuspended from the bed in the TMZ sector and is a source of sediment delivered to the tidal flats and mangroves. The seasonal variation of the sediments on the seabed is in agreement with the variation of suspended sediments as well.

  13. Late Pleistocene echimyid rodents (Rodentia, Hystricognathi) from northern Brazil.

    Science.gov (United States)

    Ferreira, Thais M F; Olivares, Adriana Itati; Kerber, Leonardo; Dutra, Rodrigo P; Avilla, Leonardo S

    2016-06-07

    Echimyidae (spiny rats, tree rats and the coypu) is the most diverse family of extant South American hystricognath rodents (caviomorphs). Today, they live in tropical forests (Amazonian, coastal and Andean forests), occasionally in more open xeric habitats in the Cerrado and Caatinga of northern South America, and open areas across the southern portion of the continent (Myocastor). The Quaternary fossil record of this family remains poorly studied. Here, we describe the fossil echimyids found in karst deposits from southern Tocantins, northern Brazil. The analyzed specimens are assigned to Thrichomys sp., Makalata cf. didelphoides and Proechimys sp. This is the first time that a fossil of Makalata is reported. The Pleistocene record of echimyids from this area is represented by fragmentary remains, which hinders their determination at specific levels. The data reported here contributes to the understanding of the ancient diversity of rodents of this region, evidenced until now in other groups, such as the artiodactyls, cingulates, carnivores, marsupials, and squamate reptiles.

  14. Amazonian vegetable oils and fats: fast typification and quality control via triacylglycerol (TAG) profiles from dry matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry fingerprinting.

    Science.gov (United States)

    Saraiva, Sérgio A; Cabral, Elaine C; Eberlin, Marcos N; Catharino, Rodrigo R

    2009-05-27

    Amazonian oils and fats display unique triacylglycerol (TAG) profiles and, because of their economic importance as renewable raw materials and use by the cosmetic and food industries, are often subject to adulteration and forgery. Representative samples of these oils (andiroba, Brazil nut, buriti, and passion fruit) and fats (cupuaçu, murumuru, and ucuúba) were characterized without pre-separation or derivatization via dry (solvent-free) matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Characteristic profiles of TAG were obtained for each oil and fat. Dry MALDI-TOF MS provides typification and direct and detailed information, via TAG profiles, of their variable combinations of fatty acids. A database from spectra could be developed and may be used for their fast and reliable typification, application screening, and quality control.

  15. Drought tolerance as predicted by leaf water potential at turgor loss point varies strongly across species within an Amazonian forest

    OpenAIRE

    2015-01-01

    1. Amazonian droughts are predicted to become increasingly frequent and intense, and the vulnerability of Amazonian trees has become increasingly documented. However, little is known about the physiological mechanisms and the diversity of drought tolerance of tropical trees due to the lack of quantitative measurements. 2. Leaf water potential at wilting or turgor loss point (pi(tlp)) is a determinant of the tolerance of leaves to drought stress and contributes to plant-level physiological...

  16. 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.

  17. Macroalgas de riachos da Serra da Prata, leste do Estado do Paraná, Sul do Brasil Stream macroalgae from Serra da Prata, eastern Paraná State, Southern Brazil

    Directory of Open Access Journals (Sweden)

    Cleto Kaveski Peres

    2008-06-01

    Full Text Available Estudos florísticos das comunidades de macroalgas lóticas no Brasil são quase que exclusivamente baseadas em material do Estado de São Paulo. Informações sobre macroalgas de riachos são escassos no Estado do Paraná. Neste contexto, o presente trabalho teve como objetivo realizar o levantamento florístico das comunidades de macroalgas de riachos da Serra da Prata, uma área bem preservada e protegida de Floresta Ombrófila Densa. As amostras foram realizadas em 14 segmentos de riachos. O levantamento resultou na identificação de 19 táxons (15 infragenéricos, três genéricos e uma fase do ciclo de vida de Batrachospermum spp., distribuídos em quatro divisões. Cyanophyta foi a divisão com maior número de representantes (58% das espécies e Microcoleus subtorulosus Gomont ex Gomont foi a espécie mais bem distribuída. A maioria dos táxons encontrados (53% são primeiros registros no Estado do Paraná, ao passo que alguns outros são considerados de ocorrência rara em riachos brasileiros. Estes resultados reforçam a importância e a necessidade de mais estudos florísticos e taxonômicos para que se amplie o conhecimento sobre a biodiversidade das comunidades de macroalgas de riacho no Brasil.Studies of stream macroalgal communities in Brazil are almost exclusively based on data from São Paulo state. There are no extensive studies concerning stream macroalgae in Paraná state. In this context, the main objective of this study was to survey the flora of stream macroalgal communities in the Serra da Prata, a well-preserved and protected area of dense Atlantic rain forest. Sampling was carried out in 14 stream segments. The survey resulted in the identification of 19 taxa (15 infrageneric, three generic and one life cycle stage of Batrachospermum spp., distributed in four divisions. Cyanophyta was the division with the highest number of taxa (58% of the species and Microcoleus subtorulosus Gomont ex Gomont was the most widespread

  18. Lymphatic filariasis in Brazil: epidemiological situation and outlook for elimination

    Directory of Open Access Journals (Sweden)

    Fontes Gilberto

    2012-11-01

    Full Text Available Abstract Since the World Health Assembly’s (Resolution WHA 50.29, 1997 call for the elimination of lymphatic filariasis by the year 2020, most of the endemic countries identified have established programmes to meet this objective. In 1997, a National Lymphatic Filariasis Elimination Plan was drawn up by the Ministry of Health of Brazil, creating local programs for the elimination of Bancroftian filariasis in areas with active transmission. Based on a comprehensive bibliographic search for available studies and reports of filariasis epidemiology in Brazil, current status of this parasitic infection and the outlook for its elimination in the country were analysed. From 1951 to 1958 a nationwide epidemiological study conducted in Brazil confirmed autochthonous transmission of Bancroftian filariasis in 11 cities of the country. Control measures led to a decline in parasite rates, and in the 1980s only the cities of Belém in the Amazonian region (Northern region and Recife (Northeastern region were considered to be endemic. In the 1990s, foci of active transmission of LF were also described in the cities of Maceió, Olinda, Jaboatão dos Guararapes, and Paulista, all in the Northeastern coast of Brazil. Data provide evidence for the absence of microfilaremic subjects and infected mosquitoes in Belém, Salvador and Maceió in the past few years, attesting to the effectiveness of the measures adopted in these cities. Currently, lymphatic filariasis is a public health problem in Brazil only in four cities of the metropolitan Recife region (Northeastern coast. Efforts are being concentrated in these areas, with a view to eliminating the disease in the country.

  19. A new species of nectar-feeding bat, genus Lonchophylla, from the Caatinga of Brazil (Chiroptera, Phyllostomidae).

    Science.gov (United States)

    Moratelli, Ricardo; Dias, Daniela

    2015-01-01

    We describe Lonchophyllainexpectata sp. n. from the Caatinga of Brazil. This new species can be distinguished from all known species of Lonchophylla that occur in Brazil by dental traits, cranial size, and fur colour. Specimens of Lonchophyllainexpectata have been misidentified as Lonchophyllamordax; but Lonchophyllainexpectata is a pale-venter species, similar in external appearance to Lonchophylladekeyseri. We have found Lonchophyllainexpectata in the Caatinga of North-eastern Brazil; Lonchophyllamordax along the eastern border of the Caatinga and in the Atlantic Forest-Caatinga ecotone in North-eastern Brazil; and Lonchophylladekeyseri in the Cerrado of Mid-western Brazil, in the Brazilian Cerrado-Caatinga ecotone, and as far west as the Cerrado of Bolivia.

  20. Arctiinae (Lepidoptera, Arctiidae ocorrentes em uma área de pastagem na Amazônia Oriental em Altamira, Pará, Brasil Arctiinae (Lepidoptera, Arctiidae occurring in a pasture area in eastern Amazon in Altamira, Pará, Brazil

    Directory of Open Access Journals (Sweden)

    Márcia Cristina Delfina

    2013-03-01

    Full Text Available O presente estudo avaliou a fauna de Arctiinae numa área de pastagem na Amazônia Oriental em Altamira-Pará, por meio de armadilha luminosa, com duas capturas mensais noturnas a cada fase da lua nova, no período de dezembro de 2008 a novembro de 2010. Foram avaliados os seguintes parâmetros: riqueza, abundância, dominância, constância, índices de diversidade e uniformidade de Shannon (H' e E' e Brillouin (H e E, dominância de Berger-Parker (BP. As estimativas de riqueza foram feitas através dos procedimentos não paramétricos, "Bootstrap", "Chao1", "Chao2", "Jackknife1", "Jackknife2", e "Michaelis-Mentem". Foram capturados 910 exemplares pertencentes a 85 espécies de Arctiinae. Os valores dos parâmetros analisados para o período total foram: H'= 2,58, E'= 0,581, H= 2,45, E= 0,576 e BP= 0,433. Para os anos, tanto a riqueza quanto a abundância foi maior em 2009-2010. A diversidade e uniformidade de Shannon e Brillouin foram maiores para o ano de 2008-2009. Os estimadores previram um aumento entre 18,8% e 85,9 % na riqueza de espécies.This study evaluated the Arctiinae fauna of a pasture area in Altamira, Pará, eastern Amazon, using light traps. The moths were captured at every new moon phase, two nights per phase, from December 2008 to November 2010. We evaluated the following parameters: richness, abundance, dominance, constancy, diversity indexes and evenness (Shannon H' and E'; Brillouin H and E, and Berger-Parker dominance (BP. Richness estimates were made by nonparametric procedures: Bootstrap, Chao1, Chao2, Jackknife1, Jackknife2 and Michaelis-Mentem. We captured a total of 910 specimens belonging to 85 species of Arctiinae. Values of parameters for the total period were: H' = 2.58, E' = 0.581, H = 2.45, E = 0.576 and BP = 0.433. Both richness and abundance were higher in 2009-2010, while diversity and Shannon and Brillouin evenness were higher for the year 2008-2009. Estimators predicted an increase between 18.8% to 85

  1. Patterns of energy allocation to reproduction in three Amazonian fish species

    Directory of Open Access Journals (Sweden)

    Rodrigo N. dos Santos

    Full Text Available The study considered the influence of the hydrological cycle and gonadal development on the accumulation and use of energy in three fish species from an Amazonian flooded area. Fishes were sampled over a 24 hour period at monthly intervals between July 2004 and June 2005 using gillnets of different mesh sizes. Body cavity fat and gonadosomatic indices were determined, as well as energy content of gonads and muscles. Amongst the studied species, different means of energy allocation for reproduction were found: Acestrorhynchus falcirostris allocate energy from body cavity fat to its gonads; Pygocentrus nattereri uses mainly energy accumulated in the muscles for the process of gonadal maturation; and Hoplosternum littorale uses energy accumulated in their muscles and body cavity fat for reproductive processes. It is quite clear that the flood pulse regulates the gain and use of the energy reserves in fishes from the Amazonian floodplain.

  2. Phenolic constituents and antioxidant activity of geopropolis from two species of amazonian stingless bees

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Ellen Cristina Costa da; Muniz, Magno Perea; Nunomura, Rita de Cassia Saraiva, E-mail: ellensilva@yahoo.com.br [Departamento de Quimica, Instituto de Ciencias Exatas, Universidade Federal do Amazonas, Manaus, AM (Brazil); Nunomura, Sergio Massayoshi [Departamento de Produtos Naturais, Instituto Nacional de Pesquisas da Amazonia, Manaus, AM (Brazil); Zilse, Gislene Almeida Carvalho [Departamento de Biodiversidade, Instituto Nacional de Pesquisas da Amazonia, Manaus, AM (Brazil)

    2013-09-01

    We investigated the phenolic constituents and antioxidant activity of geopropolis from two species of stingless Amazonian bees, Melipona interrupta and Melipona seminigra. The chemical investigation of geopropolis from Melipona interrupta led to the isolation of 5,7,4'-trihydroxyflavonone, 3,5,6,7,4'-pentahydroxyflavonol, naringenine-4'-O-{beta}-D-glucopyranoside and myricetin-3-O-{beta}-D-glucopyranoside. Their structures were assigned based on spectroscopic analyses, including two-dimensional NMR techniques. Antioxidant activity of methanol and ethanol extracts of M. interrupta and M. seminigra were measured using the 1,2-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging assay. This is also the first work reporting the chemical investigation of stingless bee species from the Amazonian region. (author)

  3. Mercury pollution in the upper Beni River, Amazonian Basin: Bolivia

    Energy Technology Data Exchange (ETDEWEB)

    Maurice-Bourgoin, L. [ORSTOM, French Scientific Research Inst. for Development by Cooperation, La Paz (Bolivia); Quiroga, Irma [Univ. Mayor de San Andres, La Paz (Bolivia). Chemical Research Inst.; Guyot, J.L. [ORSTOM, French Scientific Research Inst. for Development by Cooperation, Brasilia, DF (Brazil); Malm, O. [Univ. Federal do Rio de Janeiro, RJ (Brazil). Inst. de Biofisica

    1999-06-01

    Mercury contamination caused by the amalgamation of gold in small-scale gold mining is an environmental problem of increasing concern, particularly in tropical regions like the Amazon, where a new boom of such gold mining started in the 1970s. In Brazil, research into these problems has been carried out for many years, but there is no available data for Bolivia. The present paper surveys mercury contamination of a Bolivian river system in the Amazon drainage basin, measured in water, fish, and human hair. High concentrations in fish and human hair from consumers of carnivorous fish species are reported. The potential health risk from fish consumption was evident in people living downstream of gold-mining activities, but not in the mining population itself 24 refs, 3 figs, 2 tabs

  4. Pipes's distribution by helicopter in Amazonian forest

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Gilberto R.; Machado, Otto L.M.; Gomes, Antonio E. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2009-12-19

    The innumerable logistical problems encountered during the implementation of the gas pipeline Urucu - Coari - Manaus, located in the Amazon forest, connecting the Base Operations Geologist Pedro de Moura in Urucu to the refinery Isaac Sabba - Reman, in the city of Manaus, contributed considerably for PETROBRAS to seek non conventional solutions in the construction and assembly of pipelines in our country. Among these solutions, there is the technique of distributing pipes through cargo helicopters. The need for the usage of this technique, innovative in Brazil, comes from the lack and/or insufficiency of land access from Solimoes River to the gas pipeline main route, and the large quantities of flooded areas and/or flood plain, and also the type of soil, that together with the high index of rainfall in the region, makes the soil fully inappropriate to the traffic of heavy equipment. (author)

  5. Greenhouse gas emissions from Brazil’s Amazonian hydroelectric dams

    Science.gov (United States)

    Fearnside, Philip M.

    2016-01-01

    Tropical dams are often falsely portrayed as ‘clean’ emissions-free energy sources. The letter by de Faria et al (2015 Environ. Res. Lett. 10 124019) adds to evidence questioning this myth. Calculations are made for 18 dams that are planned or under construction in Brazilian Amazonia and show that emissions from storage hydroelectric dams would exceed those from electricity generation based on fossil fuels. Fossil fuels need not be the alternative, because Brazil has vast potential for wind and solar power as well as opportunities for energy conservation. Because dam-building is rapidly shifting to humid tropical areas, where emissions are higher than in other climatic zones, the impact of these emissions needs to be given proper weight in energy-policy decisions.

  6. Did the martian outflow channels mostly form during the Amazonian Period?

    Science.gov (United States)

    Rodriguez, J. Alexis P.; Platz, Thomas; Gulick, Virginia; Baker, Victor R.; Fairén, Alberto G.; Kargel, Jeffrey; Yan, Jianguo; Miyamoto, Hideaki; Glines, Natalie

    2015-09-01

    Simud, Tiu, and Ares Valles comprise some of the largest outflow channels on Mars. Their excavation has been attributed variously to (or a combination of) erosion by catastrophic floods, glaciers, and debris flows. Numerous investigations indicate that they formed largely during the Late Hesperian (3.61-3.37 Ga). However, these studies mostly equate the ages of the outflow channel floors to those of the flows that generated mesoscale (several hundred meters to a few kilometers) bedforms within them. To improve the statistical accuracy in the age determinations of these flow events, we have used recently acquired high-resolution image and topographic data to map and date portions of Simud, Tiu and Ares Valles, which are extensively marked by these bedforms. Our results, which remove the statistical effects of older and younger outflow channel floor surfaces on the generation of modeled ages, reveal evidence for major outflow channel discharges occurring during the Early (3.37-1.23 Ga) and Middle (1.23-0.328 Ga) Amazonian, with activity significantly peaking during the Middle Amazonian stages. We also find that during the documented stages of Middle Amazonian discharges, the floor of Tiu Valles underwent widespread collapse, resulting in chaotic terrain formation. In addition, we present evidence showing that following the outflow channel discharges, collapse within northern Simud Valles generated another chaotic terrain. This younger chaos region likely represents the latest stage of large-scale outflow channel resurfacing within the study area. Our findings imply that in southern circum-Chryse the martian hydrosphere experienced large-scale drainage during the Amazonian, which likely led to periodic inundation and sedimentation within the northern plains.

  7. Population dynamics of the yellow piranha Serrasalmus spilopleura Kner, 1858 (Characidae, Serrasalminae) in Amazonian floodplain lakes

    OpenAIRE

    Fabricio Barros Sousa; Luiza Prestes; Maria Gercilia Mota Soares

    2013-01-01

    Fish is the main source of protein in the Amazon and fishing is one of the most important sources of income for the Amazonian population. Serrasalmus spilopleura is a species that have been increasingly consumed by riverside communities, although it is only occasionally commercialized at regional markets. Therefore, this work sought to generate information about the population biology of S. spilopleura captured in floodplain lakes, jaiteua and Sao Lourenco, in Manacapuru, Amazonas State. The ...

  8. Ritualistic use of the holly Ilex guayusa by Amazonian Jívaro Indians.

    Science.gov (United States)

    Lewis, W H; Kennelly, E J; Bass, G N; Wedner, H J; Elvin-Lewis, M P; Fast, D

    1991-01-01

    In Amazonian Peru and Ecuador leaf decoctions of the rainforest holly Ilex guayusa with high caffeine concentrations are used as a morning stimulant. After daily ingestion, ritualistic vomiting by male Achuar Indians, better known as Jívaros, reduces excessive caffeine intake, so that blood levels of caffeine and biotransformed dimethylxanthines do not cause undesirable CNS and other effects. Emesis is learned and apparently not due to emetic compounds.

  9. Wood decomposition in Amazonian hydropower reservoirs: An additional source of greenhouse gases

    Science.gov (United States)

    Abril, Gwenaël; Parize, Marcelo; Pérez, Marcela A. P.; Filizola, Naziano

    2013-07-01

    Amazonian hydroelectric reservoirs produce abundant carbon dioxide and methane from large quantities of flooded biomass that decompose anaerobically underwater. Emissions are extreme the first years after impounding and progressively decrease with time. To date, only water-to-air fluxes have been considered in these estimates. Here, we investigate in two Amazonian reservoirs (Balbina and Petit Saut) the fate of above water standing dead trees, by combining a qualitative analysis of wood state and density through time and a quantitative analysis of the biomass initially flooded. Dead wood was much more decomposed in the Balbina reservoir 23 years after flooding than in the Petit Saut reservoir 10 years after flooding. Termites apparently played a major role in wood decomposition, occurring mainly above water, and resulting in a complete conversion of this carbon biomass into CO2 and CH4 at a timescale much shorter than reservoir operation. The analysis of pre-impounding wood biomass reveals that above-water decomposition in Amazonian reservoirs is a large, previously unrecognized source of carbon emissions to the atmosphere, representing 26-45% of the total reservoir flux integrated over 100 years. Accounting for both below- and above-water fluxes, we could estimate that each km2 of Amazonian forest converted to reservoir would emit over 140 Gg CO2-eq in 100 years. Hydropower plants in the Amazon should thus generate 0.25-0.4 MW h per km2 flooded area to produce lower greenhouse gas emissions than gas power plants. They also have the disadvantage to emit most of their greenhouse gases the earliest years of operation.

  10. Antifungal Resistance and Virulence Among Candida spp. from Captive Amazonian manatees and West Indian Manatees: Potential Impacts on Animal and Environmental Health.

    Science.gov (United States)

    Sidrim, José Júlio Costa; Carvalho, Vitor Luz; de Souza Collares Maia Castelo-Branco, Débora; Brilhante, Raimunda Sâmia Nogueira; de Melo Guedes, Gláucia Morgana; Barbosa, Giovanna Riello; Lazzarini, Stella Maris; Oliveira, Daniella Carvalho Ribeiro; de Meirelles, Ana Carolina Oliveira; Attademo, Fernanda Löffler Niemeyer; da Bôaviagem Freire, Augusto Carlos; de Aquino Pereira-Neto, Waldemiro; de Aguiar Cordeiro, Rossana; Moreira, José Luciano Bezerra; Rocha, Marcos Fábio Gadelha

    2016-06-01

    This work aimed at evaluating the antifungal susceptibility and production of virulence factors by Candida spp. isolated from sirenians in Brazil. The isolates (n = 105) were recovered from the natural cavities of Amazonian and West Indian manatees and were tested for the susceptibility to amphotericin B, itraconazole, and fluconazole and for the production of phospholipases, proteases, and biofilm. The minimum inhibitory concentrations (MICs) for amphotericin B ranged from 0.03 to 1 µg/mL, and no resistant isolates were detected. Itraconazole and fluconazole MICs ranged from 0.03 to 16 µg/mL and from 0.125 to 64 µg/mL, respectively, and 35.2% (37/105) of the isolates were resistant to at least one of these azole drugs. Concerning the production of virulence factors, phospholipase activity was observed in 67.6% (71/105) of the isolates, while protease activity and biofilm production were detected in 50.5% (53/105) and 32.4% (34/105) of the isolates, respectively. Since the natural cavities of manatees are colonized by resistant and virulent strains of Candida spp., these animals can act as sources of resistance and virulence genes for the environment, conspecifics and other animal species, demonstrating the potential environmental impacts associated with their release back into their natural habitat.

  11. Trypanosomes of non-human primates from the National Centre of Primates, Ananindeua, State of Pará, Brazil

    Directory of Open Access Journals (Sweden)

    Ziccardi Mariangela

    2000-01-01

    Full Text Available Trypanosome infections were sought in 46 non-human primates captured principally in Amazonian Brazil. Twenty-two (47.8% were infected with four Trypanosoma species: T. cruzi, T. minasense, T. devei and T. rangeli. These preliminary results confirmed the high prevalence and diversity of natural infections with trypanosomes in primates from Brazilian Amazon and were the first formal record of simian infections with trypanosomes in the State of Acre. The presence of T. cruzi-like and T. rangeli-like parasites are recorded in four new hosts.

  12. Nematofauna associada à cultura do quiabo na região leste de Minas Gerais The influence of parasitic nematodes on okra crop in eastern Minas Gerais State, Brazil

    Directory of Open Access Journals (Sweden)

    Rosângela D'Arc de Lima Oliveira

    2007-03-01

    of these nematodes attacking okra have already been reported in Brazil, and some of them can cause plant death. The correct identification of Meloidogyne species and, or races infecting okra roots is mandatory for choosing appropriate control measures. To determine the occurrence and distribution of Meloidogyne spp. and other nematodes in the area of the East of MG, 70 soil and root samples coming from 14 municipalities were appraised for morphological and isoenzymatic characteristics. Among the populations of Meloidogyne spp., M. incognita (Esterase phenotypes I1 and I2 prevailed and were followed by M. javanica (phenotypes J2 and J3 and M. arenaria (phenotypes A2. The species M. mayaguensis was confirmed by the phenotypes: esterase (M2, malate dehydrogenase (N3, superoxide dismutase (N2 and glutamate oxaloacetate transaminase (N3. This is the first report of the M. mayaguensis occurrence in MG. Other nematodes associated with the okra plants were Aphelenchus sp., Criconemella sp., Helicotylenchus spp., Pratylenchus brachyurus and P. coffeae, Rotylenchulus reniformis, Rotylenchus sp., Tylenchus sp. and Tylenchorhynchus sp.

  13. Avaliação de técnica de tomaticultura em gramado (TEG na amazônia oriental Evaluation of TEG (grassland tomato cropping technique in Eastern Amazon, Brazil

    Directory of Open Access Journals (Sweden)

    Simon S. Cheng

    2002-06-01

    Full Text Available No Brasil, o tomateiro é cultivado principalmente em época de baixa precipitação e temperaturas amenas como as regiões Sudeste, Nordeste e Centro Oeste. Na Amazônia Oriental, uma região tropical úmida de baixa altitude, com temperatura elevada, a cultura do tomateiro enfrenta muitas dificuldades. A baixa produtividade e a mortalidade das plantas têm reduzido o número de produtores desta hortaliça, com a produção local de tomate inferior a 0,1% do volume comercializado anualmente. A técnica de Tomaticultura Em Gramado (TEG foi concebida em 1997 e aperfeiçoada em 1998, para solucionar os problemas da tomaticultura sob clima quente e chuvoso da Amazônia, usando dois principais mecanismos: 1. Campo gramado para controlar a proliferação de doenças, pragas, plantas invasoras, erosão e lixiviação de nutrientes. 2. Queima de descarte de madeira na área de cultivo para eliminar a grama e reduzir a acidez e pobreza do solo. O presente trabalho apresenta resultados preliminares de tomaticultura sob essa nova técnica, com avaliação de produtividade, ciclo da planta e peso médio do fruto. A nova técnica de cultivo permitiu a produtividade de 5,6 ± 0,2 kg por planta, sendo o período de colheita de 60 a 80 dias. A TEG demonstrou ser uma alternativa promissora para o sistema de produção de tomate na região quente e chuvosa, usando a gramínea como protetora e limpadora do solo.In Brazil, tomatoes are cultivated principally in seasons with low precipitation and cool temperature such as in regions of Southeast, Northeast and Central west. In East Amazon, a humid tropical region of low altitude with high temperature, tomato cropping faces many difficulties. Low yield and plant mortality had reduced the number of tomato growers, with annual local production less than 0.1% of total volume commercialized. The grassland tomato cropping technique (TEG was elaborated in 1997 and improved in 1998 to solve the problems of tomato production

  14. Extremely long-distance seed dispersal by an overfished Amazonian frugivore.

    Science.gov (United States)

    Anderson, Jill T; Nuttle, Tim; Saldaña Rojas, Joe S; Pendergast, Thomas H; Flecker, Alexander S

    2011-11-22

    Throughout Amazonia, overfishing has decimated populations of fruit-eating fishes, especially the large-bodied characid, Colossoma macropomum. During lengthy annual floods, frugivorous fishes enter vast Amazonian floodplains, consume massive quantities of fallen fruits and egest viable seeds. Many tree and liana species are clearly specialized for icthyochory, and seed dispersal by fish may be crucial for the maintenance of Amazonian wetland forests. Unlike frugivorous mammals and birds, little is known about seed dispersal effectiveness of fishes. Extensive mobility of frugivorous fish could result in extremely effective, multi-directional, long-distance seed dispersal. Over three annual flood seasons, we tracked fine-scale movement patterns and habitat use of wild Colossoma, and seed retention in the digestive tracts of captive individuals. Our mechanistic model predicts that Colossoma disperses seeds extremely long distances to favourable habitats. Modelled mean dispersal distances of 337-552 m and maximum of 5495 m are among the longest ever reported. At least 5 per cent of seeds are predicted to disperse 1700-2110 m, farther than dispersal by almost all other frugivores reported in the literature. Additionally, seed dispersal distances increased with fish size, but overfishing has biased Colossoma populations to smaller individuals. Thus, overexploitation probably disrupts an ancient coevolutionary relationship between Colossoma and Amazonian plants.

  15. Estimating the global conservation status of more than 15,000 Amazonian tree species

    Science.gov (United States)

    ter Steege, Hans; Pitman, Nigel C. A.; Killeen, Timothy J.; Laurance, William F.; Peres, Carlos A.; Guevara, Juan Ernesto; Salomão, Rafael P.; Castilho, Carolina V.; Amaral, Iêda Leão; de Almeida Matos, Francisca Dionízia; de Souza Coelho, Luiz; Magnusson, William E.; Phillips, Oliver L.; de Andrade Lima Filho, Diogenes; de Jesus Veiga Carim, Marcelo; Irume, Mariana Victória; Martins, Maria Pires; Molino, Jean-François; Sabatier, Daniel; Wittmann, Florian; López, Dairon Cárdenas; da Silva Guimarães, José Renan; Mendoza, Abel Monteagudo; Vargas, Percy Núñez; Manzatto, Angelo Gilberto; Reis, Neidiane Farias Costa; Terborgh, John; Casula, Katia Regina; Montero, Juan Carlos; Feldpausch, Ted R.; Honorio Coronado, Euridice N.; Montoya, Alvaro Javier Duque; Zartman, Charles Eugene; Mostacedo, Bonifacio; Vasquez, Rodolfo; Assis, Rafael L.; Medeiros, Marcelo Brilhante; Simon, Marcelo Fragomeni; Andrade, Ana; Camargo, José Luís; Laurance, Susan G. W.; Nascimento, Henrique Eduardo Mendonça; Marimon, Beatriz S.; Marimon, Ben-Hur; Costa, Flávia; Targhetta, Natalia; Vieira, Ima Célia Guimarães; Brienen, Roel; Castellanos, Hernán; Duivenvoorden, Joost F.; Mogollón, Hugo F.; Piedade, Maria Teresa Fernandez; Aymard C., Gerardo A.; Comiskey, James A.; Damasco, Gabriel; Dávila, Nállarett; García-Villacorta, Roosevelt; Diaz, Pablo Roberto Stevenson; Vincentini, Alberto; Emilio, Thaise; Levis, Carolina; Schietti, Juliana; Souza, Priscila; Alonso, Alfonso; Dallmeier, Francisco; Ferreira, Leandro Valle; Neill, David; Araujo-Murakami, Alejandro; Arroyo, Luzmila; Carvalho, Fernanda Antunes; Souza, Fernanda Coelho; do Amaral, Dário Dantas; Gribel, Rogerio; Luize, Bruno Garcia; Pansonato, Marcelo Petrati; Venticinque, Eduardo; Fine, Paul; Toledo, Marisol; Baraloto, Chris; Cerón, Carlos; Engel, Julien; Henkel, Terry W.; Jimenez, Eliana M.; Maas, Paul; Mora, Maria Cristina Peñuela; Petronelli, Pascal; Revilla, Juan David Cardenas; Silveira, Marcos; Stropp, Juliana; Thomas-Caesar, Raquel; Baker, Tim R.; Daly, Doug; Paredes, Marcos Ríos; da Silva, Naara Ferreira; Fuentes, Alfredo; Jørgensen, Peter Møller; Schöngart, Jochen; Silman, Miles R.; Arboleda, Nicolás Castaño; Cintra, Bruno Barçante Ladvocat; Valverde, Fernando Cornejo; Di Fiore, Anthony; Phillips, Juan Fernando; van Andel, Tinde R.; von Hildebrand, Patricio; Barbosa, Edelcilio Marques; de Matos Bonates, Luiz Carlos; de Castro, Deborah; de Sousa Farias, Emanuelle; Gonzales, Therany; Guillaumet, Jean-Louis; Hoffman, Bruce; Malhi, Yadvinder; de Andrade Miranda, Ires Paula; Prieto, Adriana; Rudas, Agustín; Ruschell, Ademir R.; Silva, Natalino; Vela, César I. A.; Vos, Vincent A.; Zent, Eglée L.; Zent, Stanford; Cano, Angela; Nascimento, Marcelo Trindade; Oliveira, Alexandre A.; Ramirez-Angulo, Hirma; Ramos, José Ferreira; Sierra, Rodrigo; Tirado, Milton; Medina, Maria Natalia Umaña; van der Heijden, Geertje; Torre, Emilio Vilanova; Vriesendorp, Corine; Wang, Ophelia; Young, Kenneth R.; Baider, Claudia; Balslev, Henrik; de Castro, Natalia; Farfan-Rios, William; Ferreira, Cid; Mendoza, Casimiro; Mesones, Italo; Torres-Lezama, Armando; Giraldo, Ligia Estela Urrego; Villarroel, Daniel; Zagt, Roderick; Alexiades, Miguel N.; Garcia-Cabrera, Karina; Hernandez, Lionel; Huamantupa-Chuquimaco, Isau; Milliken, William; Cuenca, Walter Palacios; Pansini, Susamar; Pauletto, Daniela; Arevalo, Freddy Ramirez; Sampaio, Adeilza Felipe; Valderrama Sandoval, Elvis H.; Gamarra, Luis Valenzuela

    2015-01-01

    Estimates of extinction risk for Amazonian plant and animal species are rare and not often incorporated into land-use policy and conservation planning. We overlay spatial distribution models with historical and projected deforestation to show that at least 36% and up to 57% of all Amazonian tree species are likely to qualify as globally threatened under International Union for Conservation of Nature (IUCN) Red List criteria. If confirmed, these results would increase the number of threatened plant species on Earth by 22%. We show that the trends observed in Amazonia apply to trees throughout the tropics, and we predict that most of the world’s >40,000 tropical tree species now qualify as globally threatened. A gap analysis suggests that existing Amazonian protected areas and indigenous territories will protect viable populations of most threatened species if these areas suffer no further degradation, highlighting the key roles that protected areas, indigenous peoples, and improved governance can play in preventing large-scale extinctions in the tropics in this century. PMID:26702442

  16. Geology and insolation-driven climatic history of Amazonian north polar materials on Mars.

    Science.gov (United States)

    Tanaka, Kenneth L

    2005-10-13

    Mariner 9 and Viking spacecraft images revealed that the polar regions of Mars, like those of Earth, record the planet's climate history. However, fundamental uncertainties regarding the materials, features, ages and processes constituting the geologic record remained. Recently acquired Mars Orbiter Laser Altimeter data and Mars Orbiter Camera high-resolution images from the Mars Global Surveyor spacecraft and moderately high-resolution Thermal Emission Imaging System visible images from the Mars Odyssey spacecraft permit more comprehensive geologic and climatic analyses. Here I map and show the history of geologic materials and features in the north polar region that span the Amazonian period (approximately 3.0 Gyr ago to present). Erosion and redeposition of putative circumpolar mud volcano deposits (formed by eruption of liquefied, fine-grained material) led to the formation of an Early Amazonian polar plateau consisting of dark layered materials. Crater ejecta superposed on pedestals indicate that a thin mantle was present during most of the Amazonian, suggesting generally higher obliquity and insolation conditions at the poles than at present. Brighter polar layered deposits rest unconformably on the dark layers and formed mainly during lower obliquity over the past 4-5 Myr (ref. 20). Finally, the uppermost layers post-date the latest downtrend in obliquity <20,000 years ago.

  17. Commonness of Amazonian palm (Arecaceae) species: Cross-scale links and potential determinants

    Science.gov (United States)

    Kristiansen, Thea; Svenning, Jens-Christian; Grández, César; Salo, Jukka; Balslev, Henrik

    2009-07-01

    The mechanisms that cause variation in commonness (abundances and range sizes) of species remain debated in ecology, and a repeatedly observed pattern is the positive relation between local abundances and larger scale range sizes. We used the Amazonian palm species (Arecaceae) to investigate the dependence between and potential determinants of commonness across three (local, landscape, continental) spatial scales. Commonness at the smaller scales (local abundance, landscape frequency) was estimated using data from 57 transects (5 × 500 m) in primary, non-inundated ( terra firme) rainforest in a western Amazonian landscape, while commonness at the largest scale (continental range size) was estimated from digitized distribution maps. Landscape frequency was positively related to both local abundance and continental range size, which, however, were not related to each other. Landscape frequency was positively related to topographic niche breadth. Stem height correlated with continental range size and was the only species life-history trait related to any commonness measure. Distance from the study area to a species' range centre did not influence any of the commonness measures. The factors determining commonness in the Amazonian palm flora appear to be scale-dependent, with the unrelated local scale abundance and continental range size probably being controlled by different driving factors. Interestingly, commonness at the intermediate, landscape scale seems linked to both the smaller and the larger scale. Our results point towards topographic niche breadth at the smaller scales and stem height, possibly reflecting species' dispersal potential, at the continental scale as important determinants of commonness.

  18. Siliceous spicules enhance fracture-resistance and stiffness of pre-colonial Amazonian ceramics

    Science.gov (United States)

    Natalio, Filipe; Corrales, Tomas P.; Wanka, Stephanie; Zaslansky, Paul; Kappl, Michael; Lima, Helena Pinto; Butt, Hans-Jürgen; Tremel, Wolfgang

    2015-08-01

    Pottery was a traditional art and technology form in pre-colonial Amazonian civilizations, widely used for cultural expression objects, utensils and as cooking vessels. Abundance and workability of clay made it an excellent choice. However, inferior mechanical properties constrained their functionality and durability. The inclusion of reinforcement particles is a possible route to improve its resistance to mechanical and thermal damage. The Amazonian civilizations incorporated freshwater tree sponge spicules (cauixí) into the clay presumably to prevent shrinkage and crack propagation during drying, firing and cooking. Here we show that isolated siliceous spicules are almost defect-free glass fibres with exceptional mechanical stability. After firing, the spicule Young’s modulus increases (from 28 ± 5 GPa to 46 ± 8 GPa) inferring a toughness increment. Laboratory-fabricated ceramic models containing different inclusions (sand, glass-fibres, sponge spicules) show that mutually-oriented siliceous spicule inclusions prevent shrinkage and crack propagation leading to high stiffness clays (E = 836 ± 3 MPa). Pre-colonial amazonian potters were the first civilization known to employ biological materials to generate composite materials with enhanced fracture resistance and high stiffness in the history of mankind.

  19. Estimating the global conservation status of more than 15,000 Amazonian tree species.

    Science.gov (United States)

    Ter Steege, Hans; Pitman, Nigel C A; Killeen, Timothy J; Laurance, William F; Peres, Carlos A; Guevara, Juan Ernesto; Salomão, Rafael P; Castilho, Carolina V; Amaral, Iêda Leão; de Almeida Matos, Francisca Dionízia; de Souza Coelho, Luiz; Magnusson, William E; Phillips, Oliver L; de Andrade Lima Filho, Diogenes; de Jesus Veiga Carim, Marcelo; Irume, Mariana Victória; Martins, Maria Pires; Molino, Jean-François; Sabatier, Daniel; Wittmann, Florian; López, Dairon Cárdenas; da Silva Guimarães, José Renan; Mendoza, Abel Monteagudo; Vargas, Percy Núñez; Manzatto, Angelo Gilberto; Reis, Neidiane Farias Costa; Terborgh, John; Casula, Katia Regina; Montero, Juan Carlos; Feldpausch, Ted R; Honorio Coronado, Euridice N; Montoya, Alvaro Javier Duque; Zartman, Charles Eugene; Mostacedo, Bonifacio; Vasquez, Rodolfo; Assis, Rafael L; Medeiros, Marcelo Brilhante; Simon, Marcelo Fragomeni; Andrade, Ana; Camargo, José Luís; Laurance, Susan G W; Nascimento, Henrique Eduardo Mendonça; Marimon, Beatriz S; Marimon, Ben-Hur; Costa, Flávia; Targhetta, Natalia; Vieira, Ima Célia Guimarães; Brienen, Roel; Castellanos, Hernán; Duivenvoorden, Joost F; Mogollón, Hugo F; Piedade, Maria Teresa Fernandez; Aymard C, Gerardo A; Comiskey, James A; Damasco, Gabriel; Dávila, Nállarett; García-Villacorta, Roosevelt; Diaz, Pablo Roberto Stevenson; Vincentini, Alberto; Emilio, Thaise; Levis, Carolina; Schietti, Juliana; Souza, Priscila; Alonso, Alfonso; Dallmeier, Francisco; Ferreira, Leandro Valle; Neill, David; Araujo-Murakami, Alejandro; Arroyo, Luzmila; Carvalho, Fernanda Antunes; Souza, Fernanda Coelho; do Amaral, Dário Dantas; Gribel, Rogerio; Luize, Bruno Garcia; Pansonato, Marcelo Petrati; Venticinque, Eduardo; Fine, Paul; Toledo, Marisol; Baraloto, Chris; Cerón, Carlos; Engel, Julien; Henkel, Terry W; Jimenez, Eliana M; Maas, Paul; Mora, Maria Cristina Peñuela; Petronelli, Pascal; Revilla, Juan David Cardenas; Silveira, Marcos; Stropp, Juliana; Thomas-Caesar, Raquel; Baker, Tim R; Daly, Doug; Paredes, Marcos Ríos; da Silva, Naara Ferreira; Fuentes, Alfredo; Jørgensen, Peter Møller; Schöngart, Jochen; Silman, Miles R; Arboleda, Nicolás Castaño; Cintra, Bruno Barçante Ladvocat; Valverde, Fernando Cornejo; Di Fiore, Anthony; Phillips, Juan Fernando; van Andel, Tinde R; von Hildebrand, Patricio; Barbosa, Edelcilio Marques; de Matos Bonates, Luiz Carlos; de Castro, Deborah; de Sousa Farias, Emanuelle; Gonzales, Therany; Guillaumet, Jean-Louis; Hoffman, Bruce; Malhi, Yadvinder; de Andrade Miranda, Ires Paula; Prieto, Adriana; Rudas, Agustín; Ruschell, Ademir R; Silva, Natalino; Vela, César I A; Vos, Vincent A; Zent, Eglée L; Zent, Stanford; Cano, Angela; Nascimento, Marcelo Trindade; Oliveira, Alexandre A; Ramirez-Angulo, Hirma; Ramos, José Ferreira; Sierra, Rodrigo; Tirado, Milton; Medina, Maria Natalia Umaña; van der Heijden, Geertje; Torre, Emilio Vilanova; Vriesendorp, Corine; Wang, Ophelia; Young, Kenneth R; Baider, Claudia; Balslev, Henrik; de Castro, Natalia; Farfan-Rios, William; Ferreira, Cid; Mendoza, Casimiro; Mesones, Italo; Torres-Lezama, Armando; Giraldo, Ligia Estela Urrego; Villarroel, Daniel; Zagt, Roderick; Alexiades, Miguel N; Garcia-Cabrera, Karina; Hernandez, Lionel; Huamantupa-Chuquimaco, Isau; Milliken, William; Cuenca, Walter Palacios; Pansini, Susamar; Pauletto, Daniela; Arevalo, Freddy Ramirez; Sampaio, Adeilza Felipe; Valderrama Sandoval, Elvis H; Gamarra, Luis Valenzuela

    2015-11-01

    Estimates of extinction risk for Amazonian plant and animal species are rare and not often incorporated into land-use policy and conservation planning. We overlay spatial distribution models with historical and projected deforestation to show that at least 36% and up to 57% of all Amazonian tree species are likely to qualify as globally threatened under International Union for Conservation of Nature (IUCN) Red List criteria. If confirmed, these results would increase the number of threatened plant species on Earth by 22%. We show that the trends observed in Amazonia apply to trees throughout the tropics, and we predict that most of the world's >40,000 tropical tree species now qualify as globally threatened. A gap analysis suggests that existing Amazonian protected areas and indigenous territories will protect viable populations of most threatened species if these areas suffer no further degradation, highlighting the key roles that protected areas, indigenous peoples, and improved governance can play in preventing large-scale extinctions in the tropics in this century.

  20. Serosurvey for tick-borne diseases in dogs from the Eastern Amazon, Brazil Pesquisa Sorológica por doenças transmitidas por carrapatos em cães da Amazônia oriental, Brasil

    Directory of Open Access Journals (Sweden)

    Mariana Granziera Spolidorio

    Full Text Available Canine ehrlichiosis and babesiosis are the most prevalent tick-borne diseases in Brazilian dogs. Few studies have focused attention in surveying tick-borne diseases in the Brazilian Amazon region. A total of 129 blood samples were collected from dogs living in the Brazilian eastern Amazon. Seventy-two samples from dogs from rural areas of 19 municipalities and 57 samples from urban stray dogs from Santarém municipality were collected. Serum samples were submitted to Indirect Immunofluorescence Assay (IFA with antigens of Babesia canis vogeli, Ehrlichia canis, and six Rickettsia species. The frequency of dogs containing anti-B. canis vogeli, anti-E. canis, and anti-Rickettsia spp. antibodies was 42.6%, 16.2%, and 31.7%, respectively. Anti-B. canis vogeli antibodies were detected in 59.6% of the urban dogs, and in 29.1% of the rural dogs (P Ehrliquiose canina e babesiose canina são as doenças parasitárias transmitidas por carrapatos de maior prevalência em cães do Brasil. Poucos estudos pesquisaram doenças transmitidas por carrapatos na região da Amazônia brasileira. Um total de 129 amostras de sangue foram colhidas de cães da Amazônia oriental brasileira. Setenta e dois cães eram de áreas rurais de 19 municípios do Estado do Pará, e 57 amostras foram colhidas de cães errantes vadios da área urbana do município de Santarém-PA. As amostras de soro foram submetidas ao ensaio de imunofluorescência indireta, com antígenos de Babesia canis vogeli, Ehrlichia canis, e seis espécies de Rickettsia. A frequência de cães com anticorpos anti-B. canis vogeli, anti-E. canis, e anti-Rickettsia spp. foi de 42,6%, 16,2% e 31,7%, respectivamente. Anticorpos anti-B. canis vogeli foram detectados em 59,6% dos cães urbanos, e em 29,1% dos cães rurais (P < 0.05. Para E. canis, a soroprevalência foi parecida entre os cães urbanos (15,7% e rurais (16,6%. Para Rickettsia spp., cães rurais apresentaram prevalência (P < 0.05 significativamente

  1. Colour forms of Amazonian cichlid fish represent reproductively isolated species.

    Science.gov (United States)

    Ready, J S; Sampaio, I; Schneider, H; Vinson, C; Dos Santos, T; Turner, G F

    2006-07-01

    Laboratory mate choice experiments have confirmed species status for cichlid fish in the African Great Lakes that differ in colour and little else. Colour differences between allopatric populations of the South American cichlid genus Apistogramma are known for many species, yet the status of such populations has not been previously tested. Analysis of the genetic relationships and mate choice characteristics of populations previously described as Apistogramma caetei from eastern Amazonia indicates genetic differentiation into at least three allopatric lineages, which also show strong prezygotic isolation through female mate choice, confirming them as Biological species. If future studies confirm that this result is indicative of a general trend, the species richness of the South American cichlid fishes may presently be seriously underestimated.

  2. Tectonic evolution of the southern margin of the Amazonian craton in the late Mesoproterozoic based on field relationships and zircon U-Pb geochronology

    Directory of Open Access Journals (Sweden)

    GILMAR J. RIZZOTTO

    2014-03-01

    Full Text Available New U-Pb zircon geochronological data integrated with field relationships and an airborne geophysical survey suggest that the Nova Brasilândia and Aguapeí belts are part of the same monocyclic, metaigneous and metasedimentary belt formed in the late Mesoproterozoic (1150 Ma-1110 Ma. This geological history is very similar to the within-plate origin of the Sunsás belt, in eastern Bolivia. Thus, we propose that the Nova Brasilândia, Aguapeí and Sunsás belts represent a unique geotectonic unit (here termed the Western Amazon belt that became amalgamated at the end of the Mesoproterozoic and originated through the reactivation of a paleo-suture (Guaporé suture zone in an intracontinental rift environment. Therefore, its geological history involves a short, complete Wilson cycle of ca. 40 Ma. Globally, this tectonic evolution may be related with the final breakup of the supercontinent Columbia. Mafic rocks and trondhjemites in the northernmost portion of the belt yielded U-Pb zircon ages ca. 1110 Ma, which dates the high-grade metamorphism and the closure of the rift. This indicates that the breakup of supercontinent Columbia was followed in short sequence by the assembly of supercontinent Rodinia at ca. 1.1-1.0 Ga and that the Western Amazon belt was formed during the accretion of the Arequipa-Antofalla basement to the Amazonian craton.

  3. Life history and environment of Cecropia latiloba in Amazonian floodplains

    Directory of Open Access Journals (Sweden)

    Pia Parolin

    2002-06-01

    Full Text Available Cecropia latiloba can be considered to be one of the most efficient colonizers of open areas in the nutrient-rich whitewater floodplains of the Amazon river. Its main strategy to be successful is the high tolerance towards waterlogging and submergence, and the fast vertical growth and reiteration capacity. This, and the tolerance of high irradiation and sediment deposition allow C. latiloba to form large monospecific stands on open sites, and thus the first closed canopy which represents the initial phase of a successional sequence which leads to highly diverse forests. This tree is extremely well adapted to the adverse growth conditions in Amazonian floodplains with prolongued periods of flooding and seedling submergence. The species occurs on the lowest levels in the flooding gradient. Although it belongs to the most often cited species under aspects of taxonomy, species distribution and general descriptions of the ecosystem, little has been published about its ecology. In the present paper the ecological, physiological and phenological characteristics of C. latiloba are described. It is an evergreen species which constantly produces new leaves. With flooding, leaf production is reduced but new leaves are flushed also with prolongued flooding. The peak of flowering and fruiting are in the flooded period. When mature, the fruits are dispersed mainly by water and fish. Seed germination occurs, without dormancy, within 5-13 days after water retreat. In the 7 months before the first flooded period seedlings reach 1 m of height, and height growth increases until a height of 15-20 m is achieved. Photosynthetic assimilation is high, with values of up to 21 mmol CO2m-2s-1 . C. latiloba is a very flood tolerant species, and waterlogged seedlings continuously produce new leaves and adventitiuos rootsCecropia latiloba puede ser considerada una de las especies colonizadoras más eficientes de áreas abiertas en las llanuras inundadas de agua dulce, rica

  4. Energetic planning in isolated Amazonian communities using geographical information system; Planejamento energetico em regioes isoladas da Amazonia utilizando sistemas de informacoes geograficas

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Arthur [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Programa de Pos-Graduacao de Engenharia Eletrica; Rocha, Brigida R.P.; Monteiro, Jose H.A.; Gaspar, Gabriella C.M. [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Dept. de Engenharia Eletrica e de Computacao; Aarao Junior, Raimundo N.N. [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Dept. de Engenharia Mecanica

    2004-07-01

    This paper proposes a system of electric planning in isolated Amazonian communities. For those communities, we propose the use of decentralized systems of electric energy with biomass as fuel. We also propose a computer system of electric planning with geographical information systems for its facilities of integrating geographical information, so useful in an Amazonian context. (author)

  5. The Eastern Partnership

    DEFF Research Database (Denmark)

    Nielsen, Kristian L.; Vilson, Maili

    2014-01-01

    When the EU launched the Eastern Partnership (EaP) in 2009, it did so with much rhetoric about projecting its soft power into Eastern Europe. Yet today, the EU's soft power project seems to have stalled, with developments in the region being less than favourable. This article argues that the EaP ...

  6. Eastern Europe's Silicon Rush

    Science.gov (United States)

    Woodard, Colin

    2007-01-01

    This article presents how the fast expansion of information technology industry in eastern Slovakia is putting a strain on its labor supply. Suddenly, computer-science graduates have become one of the former Eastern Bloc's greatest assets, attracting multinational technology companies hungry for skilled programmers, technicians, and engineers.…

  7. False Shades of Green: The Case of Brazilian Amazonian Hydropower

    Directory of Open Access Journals (Sweden)

    James Randall Kahn

    2014-09-01

    Full Text Available The Federal Government of Brazil has ambitious plans to build a system of 58 additional hydroelectric dams in the Brazilian Amazon, with Hundreds of additional dams planned for other countries in the watershed. Although hydropower is often billed as clean energy, we argue that the environmental impacts of this project are likely to be large, and will result in substantial loss of biodiversity, as well as changes in the flows of ecological services. Moreover, the projects will generate significant greenhouse gas emissions from deforestation and decay of organic matter in the reservoirs. These emissions are equivalent to the five years of emissions that would be generated by gas powered plants of equivalent capacity. In addition, we examine the economic benefits of the hydropower in comparison to new alternatives, such as photovoltaic energy and wind power. We find that current costs of hydropower exceed alternatives, and the costs of costs of these alternatives are likely to fall substantially below those of hydropower, while the environmental damages from the dams will be extensive and irreversible.

  8. Diploid Male Production of Two Amazonian Melipona Bees (Hymenoptera: Apidae

    Directory of Open Access Journals (Sweden)

    Izaura Bezerra Francini

    2012-01-01

    Full Text Available The diploid male has already been recorded for Melipona Illger, and herein, in Melipona seminigra merrillae Cockerell and Melipona interrupta manaosensis Schwarz. This paper was carried out at the Instituto Nacional de Pesquisas da Amazônia (INPA, Manaus, AM, Brazil. We produced and monitored 31 new colonies of M. s. merrillae and 32 new colonies of M. i. manaosensis. We sampled 2,995 pupae of M. s. merrillae and 2,020 of M. i. manaosensis. In colonies with a 1 : 1 sex ratio, male diploidy was confirmed by cytogenetic analysis and workers’ behavior. We estimated 16 sex-determining alleles in M. s. merrillae and 22 in M. i. manaosensis. In colonies of M. i. manaosensis in a 1 : 1 sex ratio, workers killed the males and the queen that produced them soon after they emerged, as predicted. This behavior was not registered for M. s. merrillae, and sex ratios did not stay 1 : 1, indicating polyandry for this species.

  9. The relative role of Amazonian and non-Amazonian fires in building up the aerosol optical depth in South America: A five year study (2005-2009)

    Science.gov (United States)

    Castro Videla, Fernando; Barnaba, Francesca; Angelini, Federico; Cremades, Pablo; Gobbi, Gian Paolo

    2013-03-01

    In South America (SA) biomass burning is the major source of atmospheric aerosols. Fires are mostly registered in the dry season (July-November) and are mainly concentrated in the Amazonia and Cerrado regions. Nonetheless, the growing systematic employment of fires for land clearing and pasture maintenance across the SA continent is introducing other, potentially significant, sources of BB aerosols. This study investigates the relative contributions of different SA biomass burning regions in building up the continental aerosol load. To this purpose, the SA continent is divided into four biomass burning source regions and their impact on the aerosol optical depth (AOD) is evaluated in eight different SA target domains. The dataset used includes multi-year (2005-2009) satellite observations of both aerosol and fires and model-based atmospheric trajectories. The methodology followed couples fire counts and atmospheric transport through the definition of a specific quantity, referred to as ‘fire weighted residence time’ (FWRT), which is used to assess the contribution of the four identified fire source regions to the continental aerosol load. Results show that local fires play an important role in building up the regional aerosols load all over SA. Nevertheless, in some regions, contribution of BB aerosols transported from outside their boundaries is comparable to the local one. The major ‘smoke exporter’ regions are found to be the eastern Brazil and the Amazonia-Cerrado regions. In the dry season, due to the typical continental circulation pattern, the first is estimated to contribute to half of the AOD in Northern Amazonia, Southern Amazonia and Cerrado regions, while over 30% of the AOD in Paraguay and North Argentina derives from the Amazonia-Cerrado fires. Due to the presence of the inter-tropical convergence zone, which decouples wind circulation of the two hemispheres, regions north of the Equator (Venezuela, Guyana, Suriname) are found to receive

  10. Idiosyncratic responses of Amazonian birds to primary forest disturbance.

    Science.gov (United States)

    Moura, Nárgila G; Lees, Alexander C; Aleixo, Alexandre; Barlow, Jos; Berenguer, Erika; Ferreira, Joice; Mac Nally, Ralph; Thomson, James R; Gardner, Toby A

    2016-03-01

    As humans continue to alter tropical landscapes across the world, it is important to understand what environmental factors help determine the persistence of biodiversity in modified ecosystems. Studies on well-known taxonomic groups can offer critical insights as to the fate of biodiversity in these modified systems. Here we investigated species-specific responses of 44 forest-associated bird species with different behavioural traits to forest disturbance in 171 transects distributed across 31 landscapes in two regions of the eastern Brazilian Amazon. We investigated patterns of species occurrence in primary forests varyingly disturbed by selective-logging and fire and examined the relative importance of local, landscape and historical environmental variables in determining species occurrences. Within undisturbed and disturbed primary forest transects, we found that distance to forest edge and the biomass of large trees were the most important predictors driving the occurrence of individual species. However, we also found considerable variation in species responses to different environmental variables as well as inter-regional variation in the responses of the same species to the same environmental variables. We advocate the utility of using species-level analyses to complement community-wide responses in order to uncover highly variable and species-specific responses to environmental change that remain so poorly understood.

  11. Historical and potential future impacts of extreme hydrological events on the Amazonian floodplain hydrology and inundation dynamics

    Science.gov (United States)

    Macedo, M.; Panday, P. K.; Coe, M. T.; Lefebvre, P.; Castello, L.

    2015-12-01

    The Amazonian floodplains and wetlands cover one fifth of the basin and are highly productive promoting diverse biological communities and sustaining human populations with fisheries. Seasonal inundation of the floodplains fluctuates in response to drought or extreme rainfall as observed in the recent droughts of 2005 and 2010 where river levels dropped to among the lowest recorded. We model and evaluate the historical (1940-2010) and projected future (2010-2100) impacts of droughts and floods on the floodplain hydrology and inundation dynamics in the central Amazon using the Integrated Biosphere Simulator (IBIS) and the Terrestrial Hydrology Model and Biogeochemistry (THMB). Simulated discharge correlates well with observed discharges for tributaries originating in Brazil but underestimates basins draining regions in the non-Brazilian Amazon (Solimões, Japuŕa, Madeira, and Negro) by greater than 30%. A volume bias-correction from the simulated and observed runoff was used to correct the input precipitation across the major tributaries of the Amazon basin that drain the Andes. Simulated hydrological parameters (discharge, inundated area and river height) using corrected precipitation has a strong correlation with field measured discharge at gauging stations, surface water extent data (Global Inundation Extent from Multi-Satellites (GIEMS) and NASA Earth System Data Records (ESDRs) for inundation), and satellite radar altimetry (TOPEX/POSEIDON altimeter data for 1992-1998 and ENVISAT data for 2002-2010). We also used an ensemble of model outputs participating in the IPCC AR5 to drive two sets of simulations with and without carbon dioxide fertilization for the 2006-2100 period, and evaluated the potential scale and variability of future changes in discharge and inundation dynamics due to the influences of climate change and vegetation response to carbon dioxide fertilization. Preliminary modeled results for future scenarios using Representative Concentration

  12. Biochemical Education in Brazil.

    Science.gov (United States)

    Vella, F.

    1988-01-01

    Described are discussions held concerning the problems of biochemical education in Brazil at a meeting of the Sociedade Brazileira de Bioquimica in April 1988. Also discussed are other visits that were made to universities in Brazil. Three major recommendations to improve the state of biochemistry education in Brazil are presented. (CW)

  13. Biochemical Education in Brazil.

    Science.gov (United States)

    Vella, F.

    1988-01-01

    Described are discussions held concerning the problems of biochemical education in Brazil at a meeting of the Sociedade Brazileira de Bioquimica in April 1988. Also discussed are other visits that were made to universities in Brazil. Three major recommendations to improve the state of biochemistry education in Brazil are presented. (CW)

  14. Isotopic analysis of Bothrops atrox in Amazonian forest

    Science.gov (United States)

    Martinez, M. G.; Silva, A. M.; Chalkidis, H.; de Oliveira Júnior, R. C.; Camargo, P. B.

    2012-12-01

    The poisoning of snakes is considered a public health problem, especially in populations from rural areas of tropical and subtropical countries. In Brazil, the 26,000 snakebites, 90% are of the genus Bothrops, and Bothrops atrox species predominant in the Amazon region including all the Brazilian Amazon. Research shows that using stable isotopes, we can verify the isotopic composition of tissues of animals that depend mainly on food, water ingested and inhaled gases. For this study, samples taken from Bothrops atrox (B. atrox), in forest using pitfall traps and fall ("Pitt-fall traps with drift fence"). The analyzes were performed by mass spectrometry, where the analytical error is 0.3‰ for carbon and 0.5‰ to nitrogen. The results of the forest animals are significantly different from results of animal vivarium. The average values of the tissues and venoms of snakes of the forest for carbon-13 and nitrogen-15 are: δ13C = -24.68‰ and δ15N = 14.22‰ and mean values of tissue and poisons snakes vivarium (Instituto Butantan) to carbon-13 and nitrogen-15 are δ13C = -20.47‰ and δ15N = 8.36‰, with a significantly different due to different sources of food animals. Based on all results isotopic δ13C and δ15N, we can suggest that changes as the power of the serpent, (nature and captivity), changes occur in relation to diet and environment as the means of the isotopic data are quite distinct, showing that these changes can also cause metabolic changes in the body of the animal itself and the different periods of turnover of each tissue analyzed.

  15. Processes influencing rainfall features in the Amazonian region

    Science.gov (United States)

    Gerken, T.; Chamecki, M.; Fuentes, J. D.; Katul, G. G.; Fitzjarrald, D. R.; Manzi, A. O.; Nascimento dos Santos, R. M.; von Randow, C.; Stoy, P. C.; Tota, J.; Trowbridge, A.; Schumacher, C.; Machado, L.

    2014-12-01

    The Amazon is globally unique as it experiences the deepest atmospheric convection with important teleconnections to other parts of the Earth's climate system. In the Amazon Basin a large fraction of the local evapotranspiration is recycled through the formation of deep convective precipitating storms. Deep convection occurs due to moist thermodynamic conditions associated with elevated amounts of convective available potential energy. Aerosols invigorate the formation of convective storms in the Amazon via their unique concentrations, physical size, and chemical composition to activate into cloud condensation nuclei (CCN), but important aspects of aerosol/precipitation feedbacks remain unresolved. During the wet season, low atmospheric aerosol concentrations prevail in the pristine tropical air masses. These conditions have led to the Green Ocean hypothesis, which compares the clean tropical air to maritime air-masses and emphasizes biosphere-atmosphere feedbacks, to explain the features of the convective-type rainfall events in the Amazon. Field studies have been designed to investigate these relationships and the development of mesoscale convective systems through the Green Ocean Amazon project and the GOAmazon Boundary Layer Experiment. From March to October 2014 a field experiment was conducted at the Cuieiras Biological Reserve (2°51' S, 54°58' W), 80 km north of the city of Manaus, Brazil. This investigation spans the biological, chemical, and physical conditions influencing emissions and reactions of precursors (biogenic and anthropogenic volatile organic compounds, VOCs), formation of aerosols and CCNs and transport out of the ABL, and their role in cloud formation and precipitation triggers. In this presentation we will show results on the magnitude turbulent fluxes of latent and sensible heat, CCN concentrations, and rain droplet size distribution for both the wet and dry season. Such influencing factors on precipitation, will be contrasted with the

  16. Paleo-Mesoproterozoic arc-accretion along the southwestern margin of the Amazonian craton: The Juruena accretionary orogen and possible implications for Columbia supercontinent

    Science.gov (United States)

    Scandolara, J. E.; Correa, R. T.; Fuck, R. A.; Souza, V. S.; Rodrigues, J. B.; Ribeiro, P. S. E.; Frasca, A. A. S.; Saboia, A. M.; Lacerda Filho, J. V.

    2017-01-01

    The southwestern portion of the Amazonian craton, between the Ventuari-Tapajós province and the Andean chain, has been ascribed to a succession of orogenic events from 1.81 to 0.95 Ga, culminating with widespread anorogenic magmatism. Southwestward of the Serra do Cachimbo graben occurs the Juruena accretionary orogenic belt (ca. 1.81-1.51 Ga), previously included in the Rio Negro-Juruena and Rondonian/San Ignácio geocronological provinces or Rondônia-Juruena geologic province. The Juruena orogen proposed here includes the Jamari and Juruena tectonostratigraphic terranes, products of convergence which culminated in the soft collision of the Paraguá protocraton and the Tapajós-Parima arc system (Tapajós Province) ca. 1.69-1.63 Ga ago. Geophysical, geochemical, petrological and geochronological data and systematic geological mapping suggest that the convergent event resulted in a single orogenic system with two continental margin arcs, namely the Jamari and Juruena arcs. Modern geological and tectonic approaches, combined with aerogeophysics data, enable to interpreting this wide region of the Amazonian craton as a Paleoproterozoic orogen with well defined petrotectonic units and tectonoestructural framework. The Juruena orogen is an E-W trending belt, about 1100 km long and 350 km wide, inflecting to NW-SE, in Mato Grosso, Amazonas and Rondonia, Brazil. The general direction of the belt, its inflections and internal geometric and kinematic aspects of its macrostructures do not corroborate the general NW-SE trend of the originally proposed geocronological provinces. The Juruena accretionary orogen has been the site of repeated reactivation with renewed basin formation, magmatism and orogeny during the Mesoproterozoic and the early Neoproterozoic. U-Pb and whole-rock Sm-Nd ages, Ar-Ar and Rb-Sr mineral ages suggest that the older high grade tectonometamorphic events in the Juruena accretionary orogen took place between 1.69 and 1.63 Ga, defining the metamorphic

  17. Contribution of the institutions in the Northern region of Brazil to the development of plant cultivars and their impact on agriculture

    Directory of Open Access Journals (Sweden)

    Aparecida das Graças Claret de Souza

    2012-12-01

    Full Text Available This paper describes the development of breeding programs in northern Brazil and their main impacts on agriculture. Their contribution to the breeding of the species palm oil, acai fruit, cacao, cupuaçu, guarana, tomato, camu-camu, cocona, peach palm, and rubber was laid out in detail. Advances in breeding programs of institutions such as Embrapa, Ceplac, Inpa, and Universities require investments in infrastructure and in human and financial resources to ensure continuity and efficiency in economic, social and environmental gains. The improvement of native species, the main focus of the breeding programs of the institutions in the Northern region of Brazil, is a form of exploiting the Amazonian biodiversity for the benefit of society. Therefore, policies to foster research institutions should be a subject of deliberation and action of the scientific and technological community in Brazil.

  18. Systematics and biogeography of the Neotropical genus Mabuya, with special emphasis on the Amazonian skink Mabuya nigropunctata (Reptilia, Scincidae).

    Science.gov (United States)

    Miralles, A; Carranza, S

    2010-03-01

    Phylogenetic analyses using up to 1532 base pairs (bp) of mitochondrial DNA from 106 specimens of Neotropical Mabuya, including 18 of the 19 recognized South American and Mesoamerican species, indicate that most species of the genus are monophyletic, including M. nigropunctata that had previously been reported to be paraphyletic. The present results shows that this species includes three highly divergent and largely allopatric lineages restricted to occidental, meridional, and oriental Amazonia. Our dataset demonstrates that previous claims regarding the paraphyletic status of M. nigropunctata and the phylogenetic relationships within this species complex based on the analysis of three mitochondrial and four nuclear genes (approx. 5000bp) were erroneous and resulted from two contaminated cytochrome b sequences. The phylogenetic results indicate that diversification in the Neotropical genus Mabuya started approximately in the Middle Miocene (15.5-13.4Ma). The divergence dates estimated for the Mabuya nigropunctata species complex suggest that the major cladogenetic events that produced the three main groups (occidental (oriental+meridional)) occurred during the Late Miocene. These estimations show that diversification within the M. nigropunctata species complex was not triggered by the climatic changes that occurred during the Pleistocene, as has been suggested by several authors. Rather, our data support the hypothesis that the late tertiary (essentially Miocene epoch) was a period that played a very important role in the generation of biological diversity in the Amazonian forests. Speciation between Mabuyacarvalhoi, endemic to the coastal mountain range of Venezuela, and M. croizati, restricted to the Guiana Shield, occurred during the Middle Miocene and may have been as the result of a vicariant event produced by the formation of the present day Orinoco river drainage basin and the consequent appearance of the Llanos del Orinoco, which acted as a barrier to

  19. Elements of metacommunity structure in Amazonian Zygoptera among streams under different spatial scales and environmental conditions.

    Science.gov (United States)

    Brasil, Leandro Schlemmer; Vieira, Thiago Bernardi; de Oliveira-Junior, José Max Barbosa; Dias-Silva, Karina; Juen, Leandro

    2017-05-01

    An important aspect of conservation is to understand the founding elements and characteristics of metacommunities in natural environments, and the consequences of anthropogenic disturbance on these patterns. In natural Amazonian environments, the interfluves of the major rivers play an important role in the formation of areas of endemism through the historical isolation of species and the speciation process. We evaluated elements of metacommunity structure for Zygoptera (Insecta: Odonata) sampled in 93 Amazonian streams distributed in two distinct biogeographic regions (areas of endemism). Of sampled streams, 43 were considered to have experienced negligible anthropogenic impacts, and 50 were considered impacted by anthropogenic activities. Our hypothesis was that preserved ("negligible impact") streams would present a Clementsian pattern, forming clusters of distinct species, reflecting the biogeographic pattern of the two regions, and that anthropogenic streams would present random patterns of metacommunity, due to the loss of more sensitive species and dominance of more tolerant species, which have higher dispersal ability and environmental tolerance. In negligible impact streams, the Clementsian pattern reflected a strong biogeographic pattern, which we discuss considering the areas of endemism of Amazonian rivers. As for communities in human-impacted streams, a biotic homogenization was evident, in which rare species were suppressed and the most common species had become hyper-dominant. Understanding the mechanisms that trigger changes in metacommunities is an important issue for conservation, because they can help create mitigation measures for the impacts of anthropogenic activities on biological communities, and so should be expanded to studies using other taxonomic groups in both tropical and temperate systems, and, wherever possible, at multiple spatial scales.

  20. Fish are central in the diet of Amazonian riparians: should we worry about their mercury concentrations?

    Science.gov (United States)

    Dorea, Jose G

    2003-07-01

    The Amazon rain forest extends over an area of 7.8x10(6)km(2) in nine countries. It harbors a diverse human population distributed in dense cities and isolated communities with extreme levels of infrastructure. Amazonian forest people, either autochthons or frontier riparians (ribeirinhos) living in isolated areas, share the same environment for survival and nutritional status. The peculiarities of the hydrological cycle determine disease patterns, agricultural conditions, and food availability. Feeding strategies depend heavily on cassava products and fish. These two foods carry toxic substances such as linamarin (naturally present in cassava) and monomethyl mercury (MMHg) (bioconcentrated in fish flesh) that cause neurotoxic diseases in other parts of the world but not in Amazonia, where neurotoxic cases of food origin are rare and not related to these staples. While cassava detoxification processes may partly explain its safe consumption, the Hg concentrations in Amazonian fish are within traditionally safe limits for this population and contribute to an important metabolic interaction with cassava. The gold rush of the 1970s and 1980s brought large-scale environmental disruption and physical destruction of ecosystems at impact points, along with a heavy discharge of metallic Hg. The discharged Hg has not yet impacted on MMHg concentrations in fish or in hair of fish consumers. Hair Hg concentration, used as a biomarker of fish consumption, indicates that the Amazonian riparians are acquiring an excellent source of protein carrying important nutrients, the lack of which could aggravate their existing health problems. Therefore, in a scenario of insufficient health services and an unhealthy environment, food habits based on fish consumption are part of a successful survival strategy and recommendations for changes are not yet justifiable.

  1. The role of tectonics and climate in the late Quaternary evolution of a northern Amazonian River

    Science.gov (United States)

    Cremon, Édipo Henrique; Rossetti, Dilce de Fátima; Sawakuchi, André de Oliveira; Cohen, Marcelo Cancela Lisboa

    2016-10-01

    The Amazon basin has most of the largest rivers of the world. However, works focusing the geological evolution of the trunk river or its tributaries have been only partly approached. The Branco River constitutes one of the main northern Amazonian tributaries. A previous work proposed that, before flowing southward into the Negro-Amazon Rivers, the Branco River had a southwest to northeast course into the Caribbean Sea. The present work aimed to establish if the proposed change in the course of this river is supported by morphological and sedimentological data. Other goals were to discuss the factors influencing river development and establish its evolution over time within the chronological framework provided by radiocarbon and optically stimulated luminescence dating. The work considered the entire course of the Branco River downstream of the Precambrian Guiana Shield, where the river presumably did not exist in ancient times. The river valley is incised into fluvial sedimentary units displaying ages between 100 and 250 ky old, which record active and abandoned channels, crevasse splay/levees, and point bars. The sedimentary deposits in the valley include two alluvial plain units as old as 18.7 ky and which intersects a Late Pleistocene residual megafan. These characteristics suggest that a long segment of the Branco River was established only a few thousand years ago. Together with several structural anomalies, these data are consistent with a mega-capture at the middle reach of this river due to tectonic reactivation in the Late Pleistocene. This integrated approach can be applied to other Amazonian tributaries to unravel how and when the Amazonian drainage basin became established.

  2. Endocrine monitoring of the ovarian cycle in captive female Amazonian manatees (Trichechus inunguis).

    Science.gov (United States)

    Amaral, Rodrigo S; Rosas, Fernando C W; da Silva, Vera M F; Nichi, Marcilio; Oliveira, Claudio A

    2013-11-01

    The Amazonian manatee (Trichechus inunguis; Mammalia: Sirenia), a threatened aquatic mammal endemic to the Amazon basin, is the only sirenian that lives exclusively in fresh water. Information about the reproductive endocrinology of the Amazonian manatee is scarce; therefore, the aim of this study was to monitor salivary progesterone and estradiol patterns during the ovarian cycle in T. inunguis. Salivary samples were collected daily during a 12-week period of two consecutive years from two captive adult females. The salivary estradiol and progesterone were measured by enzyme immunoassay. The results were analyzed in an iterative process of excluding values that were higher than the mean plus 2 standard deviations until the basal values were determined. The interval between two peaks of salivary estradiol followed by a rise of progesterone was considered as one complete cycle for the calculation of the cycle length. We observed only three complete cycles in all samples analyzed. The cycle length ranged from 42 to 48 days (mean of 44.67 days). We also observed two distinct salivary estradiol peaks during all cycles analyzed, with the first peak occurring before the rise in salivary progesterone and the second occurred followed by a return to basal progesterone levels. This is the first in-depth study of the ovarian cycle in Amazonian manatees. Our results demonstrate that salivary samples can be a useful tool in the endocrine monitoring of this species and suggest that T. inunguis shows a peculiar hormonal pattern during the ovarian cycle, a finding that may have physiological and ecological significance in the reproductive strategy of these animals.

  3. Investigation of host candidate malaria-associated risk/protective SNPs in a Brazilian Amazonian population.

    Directory of Open Access Journals (Sweden)

    Simone da Silva Santos

    Full Text Available The Brazilian Amazon is a hypo-endemic malaria region with nearly 300,000 cases each year. A variety of genetic polymorphisms, particularly in erythrocyte receptors and immune response related genes, have been described to be associated with susceptibility and resistance to malaria. In order to identify polymorphisms that might be associated with malaria clinical outcomes in a Brazilian Amazonian population, sixty-four human single nucleotide polymorphisms in 37 genes were analyzed using a Sequenom massARRAY iPLEX platform. A total of 648 individuals from two malaria endemic areas were studied, including 535 malaria cases (113 individuals with clinical mild malaria, 122 individuals with asymptomatic infection and 300 individuals with history of previous mild malaria and 113 health controls with no history of malaria. The data revealed significant associations (p<0.003 between one SNP in the IL10 gene (rs1800896 and one SNP in the TLR4 gene (rs4986790 with reduced risk for clinical malaria, one SNP in the IRF1 gene (rs2706384 with increased risk for clinical malaria, one SNP in the LTA gene (rs909253 with protection from clinical malaria and one SNP in the TNF gene (RS1800750 associated with susceptibility to clinical malaria. Also, a new association was found between a SNP in the CTL4 gene (rs2242665, located at the major histocompatibility complex III region, and reduced risk for clinical malaria. This study represents the first association study from an Amazonian population involving a large number of host genetic polymorphisms with susceptibility or resistance to Plasmodium infection and malaria outcomes. Further studies should include a larger number of individuals, refined parameters and a fine-scale map obtained through DNA sequencing to increase the knowledge of the Amazonian population genetic diversity.

  4. Amazonian-aged fluvial system and associated ice-related features in Terra Cimmeria, Mars

    Science.gov (United States)

    Adeli, Solmaz; Hauber, Ernst; Kleinhans, Maarten; Le Deit, Laetitia; Platz, Thomas; Fawdon, Peter; Jaumann, Ralf

    2016-10-01

    The Martian climate throughout the Amazonian is widely believed to have been cold and hyper-arid, very similar to the current conditions. However, ubiquitous evidence of aqueous and glacial activity has been recently reported, including channels that can be tens to hundreds of kilometres long, alluvial and fluvial deposits, ice-rich mantles, and glacial and periglacial landforms. Here we study a ∼340 km-long fluvial system located in the Terra Cimmeria region, in the southern mid-latitudes of Mars. The fluvial system is composed of an upstream catchment system with narrow glaciofluvial valleys and remnants of ice-rich deposits. We observe depositional features including fan-shaped deposits, and erosional features such as scour marks and streamlined islands. At the downstream section of this fluvial system is an outflow channel named Kārūn Valles, which displays a unique braided alluvial fan and terminates on the floor of the Ariadnes Colles basin. Our observations point to surface runoff of ice/snow melt as the water source for this fluvial activity. According to our crater size-frequency distribution analysis the entire fluvial system formed during early to middle Amazonian, between ∼ 1.8-0.2+0.2 Ga to 510-40+40 Ma. Hydraulic modelling indicates that the Kārūn Valles and consequently the alluvial fan formation took place in geologically short-term event(s). We conclude that liquid water was present in Terra Cimmeria during the early to middle Amazonian, and that Mars during that time may have undergone several episodic glacial-related events.

  5. The mammary glands of the Amazonian manatee, Trichechus inunguis (Mammalia: Sirenia): morphological characteristics and microscopic anatomy.

    Science.gov (United States)

    Rodrigues, Fernanda Rosa; da Silva, Vera Maria Ferreira; Barcellos, José Fernando Marques

    2014-08-01

    The mammaries from carcasses of two female Amazonian manatees were examined. Trichechus inunguis possesses two axillary mammaries beneath the pectoral fins, one on each side of the body. Each papilla mammae has a small hole on its apex--the ostium papillare. The mammaries are covered by a stratified squamous keratinized epithelium. The epithelium of the mammary ducts became thinner more deeply in the tissue and varied from stratified to simple cuboidal. There was no evidence of glandular activity or secretion into the ducts of the mammary glands.

  6. Noninvasive monitoring of androgens in male Amazonian manatee (Trichechus inunguis): biologic validation.

    Science.gov (United States)

    Amaral, Rodrigo de Souza; Rosas, Fernando Cesar Weber; Viau, Priscila; d'Affonsêca Neto, José Anselmo; da Silva, Vera Maria Ferreira; de Oliveira, Cláudio Alvarenga

    2009-09-01

    The Amazonian manatee (Trichechus inunguis) is endemic in the Amazonian basin and is the only exclusively fresh water sirenian. Historically hunted on a large scale, this species is now considered endangered, and studies on the reproductive physiology are critical for the improvement of reproductive management of captive and wild populations of manatees. The aim of this study was to verify the viability of androgen measurement in saliva, lacrimal, urine, and fecal samples of the Amazonian manatee by conducting a hormone challenge. Two adult male manatees (A-1 and A-2) were submitted to an experimentation protocol of 12 day (D1 to D10). On D0, the animals received an intramuscular injection of gonadotropin-releasing hormone (GnRH)-analogue. Salivary, lacrimal, urinary, and fecal samples were collected daily (between 0800 hours and 0900 hours) and frozen at -20 degrees C until assayed. Fecal samples were lyophilized, extracted with 80% methanol, and diluted in buffer before the radioimmunoassay (RIA). Urine samples underwent acid hydrolysis and were diluted in depleted bovine serum. Salivary and lacrimal samples were assayed without the extraction step. Hormonal assays were conducted with a commercial testosterone RIA kit. An androgen peak (> median + 2 interquartile range [IQR]) was observed in all matrices of both animals, although it was less prominent in the lacrimal samples of A-2. However, the fecal androgen peak (A-1 peak = 293.78 ng/g dry feces, median [IQR] = 143.58 [32.38] ng/g dry feces; A-2 peak = 686.72 ng/g dry feces, median [IQR] = 243.82 [193.16] ng/g dry feces) occurred later than urinary (A-1 peak = 648.16 ng/mg creatinine [Cr], median [IQR] = 23.88 [30.44] ng/mg Cr; A-2 peak = 370.44 ng/mg Cr, median [IQR] = 113.87 [117.73] ng/mg Cr) and salivary (A-1 peak = 678.89 pg/ml, median [IQR] = 103.69 [119.86] pg/ml; A-2 peak = 733.71 pg/ml, median [IQR] = 262.92 [211.44] pg/ml) androgen peaks. These intervals appear to be correlated with the long digesta

  7. Eastern Equine Encephalitis

    Science.gov (United States)

    ... bite of an infected mosquito. Eastern equine encephalitis (EEE) is a rare illness in humans, and only ... EEEV have no apparent illness. Severe cases of EEE (involving encephalitis, an inflammation of the brain) begin ...

  8. Media, State and Society in Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Julián Durazo Herrmann

    2016-08-01

    Full Text Available In this paper, I seek to assess the role of the media in ongoing subnational democratization processes from a State-in-society perspective. I use the case of Bahia, a state in North-Eastern Brazil, to assess ownership and social access to the media, the media’s autonomy from both the State and social actors as well as how conflicts between public interest and private profit are solved. We will thus understand the role of subnational media in sustaining pluralism and in providing independent sources of information, two critical dimensions of democracy.

  9. Urban agriculture in Santarém, Pará, Brazil: diversity and circulation of cultivated plants in urban homegardens

    Directory of Open Access Journals (Sweden)

    Antoinette WinklerPrins

    Full Text Available Urban agriculture, including urban homegardens, is vital for urban survival of many people in various cities around the world, including those in the Amazon region of Brazil. These spaces, through daily praxis, become important for incidental agrodiversity conservation as food plants are cultivated and their plant material circulated. Utilizing data from a year-long intensive qualitative study of 25 rural-urban migrant households, this article considers the diversity of plant material in urban homegardens in the Amazonian city of Santarém, Pará, Brazil. The purpose of the study was to understand the social systems that maintain cultivated plant diversity in homegardens. Our objectives in this article are twofold: a to demonstrate that plant agrodiversity in homegardens persists in a setting which is located 'at the market'; and b to document the ways in which flows of plant material help maintain this agrodiversity.

  10. A new troglomorphic species of Harmonicon (Araneae, Mygalomorphae, Dipluridae) from Pará, Brazil, with notes on the genus

    Science.gov (United States)

    Pedroso, Denis Rafael; Baptista, Renner Luiz Cerqueira

    2014-01-01

    Abstract A new species of Harmonicon F. O. Pickard-Cambridge, 1896 (Araneae, Dipluridae) is described, from a medium-sized lateritic cave in Parauapebas, Pará, Brazil. The male holotype and only specimen known of H. cerberus sp. n. was found near the entrance of Pequiá cave. This taxon is the fourth species described and the southernmost record for the genus. The new species displays some troglomorphic characteristics, such as reduction and merging of the posterior median and both pairs of lateral eyes and pale yellow to light brown coloration. Both characters are diagnostic when compared to the normal separated eyes and reddish to dark brown of other Harmonicon species. Other diagnostic characteristics are isolated, long, rigid setae distal to the lyra and the shape of the copulatory bulb. This is the second troglomorphic mygalomorph species from Brazil and the first from the Amazonian region. PMID:24715775

  11. DMFT index and oral mucosal lesions associated with HIV infection: cross-sectional study in Porto Velho, Amazonian region - Brazil

    Directory of Open Access Journals (Sweden)

    Rodrigo Queiroz Aleixo

    Full Text Available We evaluated the DMFT (decayed, missing and filled teeth index and the prevalence of candidiasis, linear gingival erythema, oral hairy leukoplakia, herpes simplex, aphthous ulcers, Kaposi's sarcoma and lymphoma, as well as the association with TCD4 count, viral load (VL and antiretroviral therapy (ART in 140 HIV-infected adult individuals. A standardized examination to determine the DMFT index and the presence of oral lesions was conducted. Demographic data, TCD4 count and use of ART were obtained from medical records. A high number of decayed teeth detected among patients undergoing ART resulted in a mean DMFT of 16.9 teeth. It was observed that 24.2% of the individuals had at least one oral lesion. Candidiasis was the most frequent lesion and was associated with the TCD4 count. Oral hairy leukoplakia was associated with an increased VL. Regular use of ART was inversely associated with the occurrence of lesions. Overall, the studied population showed low prevalence of oral lesions and high DMFT index. The use of ART seems to reduce the occurrence of these lesions. Higher TCD4 count and a lower VL were associated with an improved oral health status in HIV + individuals

  12. Cross-sectional study defines difference in malaria morbidity in two Yanomami communities on Amazonian boundary between Brazil and Venezuela

    Directory of Open Access Journals (Sweden)

    Teodardo José Marcano

    2004-06-01

    Full Text Available It is well established that immunity to malaria is short-lived and is maintained by the continuous contact with the parasite. We now show that the stable transmission of malaria in Yanomami Amerindian communities maintains a degree of immunity in the exposed population capable to reduce prevalence and morbidity of malaria. We examined 508 Yanomami Amerindians living along Orinoco (407 and Mucajaí (101 rivers, on the Venezuelan and Brazilian Amazon region, respectively. At Orinoco villages, malaria was hyperendemic and presented stable transmission, while at Mucajaí villages it was mesoendemic and showed unstable transmission. The frequency of Plasmodium vivax and P. falciparum was roughly comparable in Venezuelan and Brazilian communities. Malaria presented different profiles at Orinoco and Mucajaí villages. In the former communities, malaria showed a lower prevalence (16% x 40.6%, particularly among those over 10 years old (5.2% x 34.8%, a higher frequency of asymptomatic cases (38.5% x 4.9%, and a lower frequency of cases of severe malaria (9.2% x 36.5%. Orinoco villagers also showed a higher reactivity of the immune system, measured by the frequency of splenomegaly (72.4% x 29.7% and by the splenic index (71.4% over level 1 x 28.6, and higher prevalence (91.1% x 72.1% and mean titer (1243 x 62 of antiplasmodial IgG antibodies, as well as a higher prevalence (77.4% x 24.7% and mean titer (120 x 35 of antiplasmodial IgM antibodies. Our findings show that in isolated Yanomami communities the stability of malaria transmission, and the consequent continuous activation of the immune system of the exposed population, leads to the reduction of malaria prevalence and morbidity.

  13. DMFT index and oral mucosal lesions associated with HIV infection: cross-sectional study in Porto Velho, Amazonian region - Brazil

    Directory of Open Access Journals (Sweden)

    Rodrigo Queiroz Aleixo

    2010-10-01

    Full Text Available We evaluated the DMFT (decayed, missing and filled teeth index and the prevalence of candidiasis, linear gingival erythema, oral hairy leukoplakia, herpes simplex, aphthous ulcers, Kaposi's sarcoma and lymphoma, as well as the association with TCD4 count, viral load (VL and antiretroviral therapy (ART in 140 HIV-infected adult individuals. A standardized examination to determine the DMFT index and the presence of oral lesions was conducted. Demographic data, TCD4 count and use of ART were obtained from medical records. A high number of decayed teeth detected among patients undergoing ART resulted in a mean DMFT of 16.9 teeth. It was observed that 24.2% of the individuals had at least one oral lesion. Candidiasis was the most frequent lesion and was associated with the TCD4 count. Oral hairy leukoplakia was associated with an increased VL. Regular use of ART was inversely associated with the occurrence of lesions. Overall, the studied population showed low prevalence of oral lesions and high DMFT index. The use of ART seems to reduce the occurrence of these lesions. Higher TCD4 count and a lower VL were associated with an improved oral health status in HIV + individuals

  14. Endoparasites infecting the semiaquatic coral snake Micrurus surinamensis (Squamata: Elapidae) in the southern Amazonian region, Mato Grosso state, Brazil.

    Science.gov (United States)

    Ávila, R W; Morais, D H; Anjos, L A; Almeida, W O; Silva, R J

    2013-08-01

    A parasitological survey was conducted in specimens of the semiaquatic coral snake Micrurus surinamensis, a poorly known South American elapid. Four specimens collected at the southern Amazon region in the Brazilian state of Mato Grosso were analyzed for endoparasites. Three parasite species were recovered from the snake hosts: the pentastomid Sebekia oxycephala, the nematode Physaloptera sp. and the trematode Opisthogonimus lecithonotus. This represents new locality and host record for S. oxycephala and O. lecithonotus.

  15. Endoparasites infecting the semiaquatic coral snake Micrurus surinamensis (Squamata: Elapidae in the southern amazonian region, Mato Grosso state, Brazil

    Directory of Open Access Journals (Sweden)

    RW. Ávila

    Full Text Available A parasitological survey was conducted in specimens of the semiaquatic coral snake Micrurus surinamensis, a poorly known South American elapid. Four specimens collected at the southern Amazon region in the Brazilian state of Mato Grosso were analyzed for endoparasites. Three parasite species were recovered from the snake hosts: the pentastomid Sebekia oxycephala, the nematode Physaloptera sp. and the trematode Opisthogonimus lecithonotus. This represents new locality and host record for S. oxycephala and O. lecithonotus.

  16. Minor components in oils obtained from Amazonian palm fruits

    Directory of Open Access Journals (Sweden)

    Santos, M. F.G.

    2013-12-01

    Full Text Available This study deals with the characterization of minor compounds in oils obtained from the mesocarp of fruits of the main palm species from the State of Amapá, Brazil, i.e. bacaba (Oenocarpus bacaba, buriti (Mauritia flexuosa, inajá (Maximiliana maripa, pupunha (Bactris gasipaes and tucumã (Astrocaryum vulgare. The concentration of minor glyceridic compounds, i.e. dimeric triacylglycerols (TAG, the oxidized TAG and diacylglycerols (DAG related to oil quality, and the compounds of unsaponifiable matter, i.e. hydrocarbons, aliphatic alcohols, sterols and tocopherols have been determined. The results indicate that the extracted oils had good initial quality, with DAG as the major glyceridic compound. The contents of hydrocarbons (50-734 mg·kg–1 and aliphatic alcohols (80-490 mg·kg–1 were highly variable with inajá oil containing the highest contents. In the case of tocopherols, buriti (1567 mg·kg–1 and tucumã (483 mg·kg–1 oils had the highest contents and the presence of significant amounts of tocotrienols was only detected in inajá oil. Finally, high concentrations of sterols were found in all the samples, particularly in the oils from pupunha (4456 mg·kg–1 and tucumã (2708 mg·kg–1, with β-sitosterol being the major sterol in all the samples with percentages between 65 and 83%.El objetivo de este estudio fue la caracterización de los componentes menores presentes en los aceites obtenidos del mesocarpio de frutos de especies de bacaba (Oenocarpus bacaba, buriti (Mauritia flexuosa, inajá (Maximiliana maripa, pupuña (Bactris gasipaes y tucumá (Astrocaryum vulgare, de importante producción en el Estado de Amapá, Brasil. Se determinaron las dos principales fracciones presentes en los aceites. Por una parte, los compuestos menores derivados de los componentes mayoritarios o triglicéridos (TAG: dímeros de TAG, TAG oxidados y diglicéridos (DAG relacionados con la calidad de los aceites y, por otra, los principales grupos

  17. Disease concepts and treatment by tribal healers of an Amazonian forest culture

    Directory of Open Access Journals (Sweden)

    Plotkin Mark J

    2009-10-01

    Full Text Available Abstract Background The extensive medicinal plant knowledge of Amazonian tribal peoples is widely recognized in the scientific literature and celebrated in popular lore. Despite this broad interest, the ethnomedical systems and knowledge of disease which guide indigenous utilization of botanical diversity for healing remain poorly characterized and understood. No study, to our knowledge, has attempted to directly examine patterns of actual disease recognition and treatment by healers of an Amazonian indigenous culture. Methods The establishment of traditional medicine clinics, operated and directed by elder tribal shamans in two remote Trio villages of the Suriname rainforest, presented a unique investigational opportunity. Quantitative analysis of clinic records from both villages permitted examination of diseases treated over a continuous period of four years. Cross-cultural comparative translations were articulated of recorded disease conditions through ethnographic interviews of elder Trio shamans and a comprehensive atlas of indigenous anatomical nomenclature was developed. Results 20,337 patient visits within the period 2000 to 2004 were analyzed. 75 disease conditions and 127 anatomical terms are presented. Trio concepts of disease and medical practices are broadly examined within the present and historical state of their culture. Conclusion The findings of this investigation support the presence of a comprehensive and highly formalized ethnomedical institution within Trio culture with attendant health policy and conservation implications.

  18. Young organic matter as a source of carbon dioxide outgassing from Amazonian rivers

    Energy Technology Data Exchange (ETDEWEB)

    Mayorga, E; Aufdenkampe, A K; Masiello, C A; Krusche, A V; Hedges, J I; Quay, P D; Richey, J E; Brown, T A

    2005-06-23

    Rivers are generally supersaturated with respect to carbon dioxide, resulting in large gas evasion fluxes that can be a significant component of regional net carbon budgets. Amazonian rivers were recently shown to outgas more than ten times the amount of carbon exported to the ocean in the form of total organic carbon or dissolved inorganic carbon. High carbon dioxide concentrations in rivers originate largely from in situ respiration of organic carbon, but little agreement exists about the sources or turnover times of this carbon. Here we present results of an extensive survey of the carbon isotope composition ({sup 13}C and {sup 14}C) of dissolved inorganic carbon and three size-fractions of organic carbon across the Amazonian river system. We find that respiration of contemporary organic matter (less than 5 years old) originating on land and near rivers is the dominant source of excess carbon dioxide that drives outgassing in mid-size to large rivers, although we find that bulk organic carbon fractions transported by these rivers range from tens to thousands of years in age. We therefore suggest that a small, rapidly cycling pool of organic carbon is responsible for the large carbon fluxes from land to water to atmosphere in the humid tropics.

  19. Enzymes of energy metabolism in hatchlings of amazonian freshwater turtles (Testudines, Podocnemididae).

    Science.gov (United States)

    Duncan, W P; Marcon, J L

    2009-05-01

    The metabolic profiles of selected tissues were analyzed in hatchlings of the Amazonian freshwater turtles Podocnemis expansa, P. unifilis and P. sextuberculata. Metabolic design in these species was judged based on the key enzymes of energy metabolism, with special emphasis on carbohydrate, lipid, amino acid and ketone body metabolism. All species showed a high glycolytic potential in all sampled tissues. Based on low levels of hexokinase, glycogen may be an important fuel for these species. The high lactate dehydrogenase activity in the liver may play a significant role in carbohydrate catabolism, possibly during diving. Oxidative metabolism in P. sextuberculata appears to be designed for the use of lipids, amino acids and ketone bodies. The maximal activities of 3-hydroxyacyl-CoA dehydrogenase, malate dehydrogenase, glutamine dehydrogenase, alanine aminotransferase and succinyl-CoA keto transferase display high aerobic potential, especially in muscle and liver tissues of this species. Although amino acids and ketone bodies may be important fuels for oxidative metabolism, carbohydrates and lipids are the major fuels used by P. expansa and P. unifilis. Our results are consistent with the food habits and lifestyle of Amazonian freshwater turtles. The metabolic design, based on enzyme activities, suggests that hatchlings of P. unifilis and P. expansa are predominately herbivorous, whereas P. sextuberculata rely on a mixed diet of animal matter and vegetation.

  20. Seed odor mediates an obligate ant-plant mutualism in Amazonian rainforests.

    Science.gov (United States)

    Youngsteadt, Elsa; Nojima, Satoshi; Häberlein, Christopher; Schulz, Stefan; Schal, Coby

    2008-03-25

    Seed dispersal mutualisms are essential for the survival of diverse plant species and communities worldwide. Among invertebrates, only ants have a major role in seed dispersal, and thousands of plant species produce seeds specialized for ant dispersal in "diffuse" multispecies interactions. An outstanding but poorly understood ant-seed mutualism occurs in the Amazonian rainforest, where arboreal ants collect seeds of several epiphyte species and cultivate them in nutrient-rich nests, forming abundant and conspicuous hanging gardens known as ant-gardens (AGs). AG ants and plants are dominant members of lowland Amazonian ecosystems, and their interaction is both specific and obligate, but the means by which ants locate, recognize, and accept their mutualist seeds while rejecting other seeds is unknown. Here we address the chemical and behavioral basis of the AG interaction. We show that workers of the AG ant Camponotus femoratus are attracted to odorants emanating from seeds of the AG plant Peperomia macrostachya, and that chemical cues also elicit seed-carrying behavior. We identify five compounds from P. macrostachya seeds that, as a blend, attract C. femoratus workers. This report of attractive odorants from ant-dispersed seeds illustrates the intimacy and complexity of the AG mutualism and begins to illuminate the chemical basis of this important and enigmatic interaction.

  1. Scale dependence of the simulated impact of Amazonian deforestation on regional climate

    Science.gov (United States)

    Pitman, A. J.; Lorenz, R.

    2016-09-01

    Using a global climate model, Amazonian deforestation experiments are conducted perturbing 1, 9, 25, 81 and 121 grid points, each with 5 ensemble members. All experiments show warming and drying over Amazonia. The impact of deforestation on temperature, averaged either over the affected area or a wider area, decreases by a factor of two as the scale of the perturbation increases from 1 to 121 grid points. This is associated with changes in the surface energy balance and consequential impacts on the atmosphere above the regions deforested. For precipitation, as the scale of deforestation increases from 9 to 121 grid points, the reduction in rainfall over the perturbed area decreases from ˜1.5 to ˜1 mm d-1. However, if the surrounding area is considered and large deforestation perturbations made, compensatory increases in precipitation occur such that there is little net change. This is largely associated with changes in horizontal advection of moisture. Disagreements between climate model experiments on how Amazonian deforestation affects precipitation and temperature are, at least in part, due to the spatial scale of the region deforested, differences in the areas used to calculate averages and whether areas surrounding deforestation are included in the overall averages.

  2. Seasonal variation in urinary and salivary reproductive hormone levels in Amazonian manatees (Trichechus inunguis).

    Science.gov (United States)

    Amaral, Rodrigo S; Rosas, Fernando C W; da Silva, Vera M F; Graham, Laura H; Viau, Priscila; Nichi, Marcilio; Oliveira, Claudio A

    2015-09-01

    The Amazonian manatee (Trichechus inunguis) is a threatened aquatic mammal endemic to the Amazon basin. The aim of this study was to evaluate the urinary and salivary reproductive hormone levels of captive Amazonian manatees collected during two seasons of the year. Salivary samples from four males and urinary and salivary samples from three females were collected during two seasons (March-June and September-November) over two consecutive years. Salivary testosterone in males was measured by radioimmunoassay and reproductive hormones in females (salivary progesterone and oestradiol and urinary progestogens, oestrogens and luteinising hormone) were measured by enzyme immunoassay. The data were analysed in a 2×2 factorial design, where the factors were year and season. There was no effect of year or season for salivary testosterone. All female hormones showed a seasonal effect (higher hormone levels during March-June than September-November) or an interaction between year and season (Pmanatees; however, apparently only females exhibit reproductive quiescence during the non-breeding season. Further long-term studies are necessary to elucidate which environmental parameters are related to reproductive seasonality in T. inunguis and how this species responds physiologically to those stimuli.

  3. The discovery of the Amazonian tree flora with an updated checklist of all known tree taxa

    Science.gov (United States)

    Ter Steege, Hans; Vaessen, Rens W.; Cárdenas-López, Dairon; Sabatier, Daniel; Antonelli, Alexandre; de Oliveira, Sylvia Mota; Pitman, Nigel C. A.; Jørgensen, Peter Møller; Salomão, Rafael P.

    2016-07-01

    Amazonia is the most biodiverse rainforest on Earth, and the debate over how many tree species grow there remains contentious. Here we provide a checklist of all tree species collected to date, and describe spatial and temporal trends in data accumulation. We report 530,025 unique collections of trees in Amazonia, dating between 1707 and 2015, for a total of 11,676 species in 1225 genera and 140 families. These figures support recent estimates of 16,000 total Amazonian tree species based on ecological plot data from the Amazonian Tree Diversity Network. Botanical collection in Amazonia is characterized by three major peaks, centred around 1840, 1920, and 1980, which are associated with flora projects and the establishment of inventory plots. Most collections were made in the 20th century. The number of collections has increased exponentially, but shows a slowdown in the last two decades. We find that a species’ range size is a better predictor of the number of times it has been collected than the species’ estimated basin-wide population size. Finding, describing, and documenting the distribution of the remaining species will require coordinated efforts at under-collected sites.

  4. Do soil fertilization and forest canopy foliage affect the growth and photosynthesis of Amazonian saplings?

    Directory of Open Access Journals (Sweden)

    Nilvanda dos Santos Magalhães

    2014-02-01

    Full Text Available Most Amazonian soils are highly weathered and poor in nutrients. Therefore, photosynthesis and plant growth should positively respond to the addition of mineral nutrients. Surprisingly, no study has been carried out in situ in the central Amazon to address this issue for juvenile trees. The objective of this study was to determine how photosynthetic rates and growth of tree saplings respond to the addition of mineral nutrients, to the variation in leaf area index of the forest canopy, and to changes in soil water content associated with rainfall seasonality. We assessed the effect of adding a slow-release fertilizer. We determined plant growth from 2010 to 2012 and gas exchange in the wet and dry season of 2012. Rainfall seasonality led to variations in soil water content, but it did not affect sapling growth or leaf gas exchange parameters. Although soil amendment increased phosphorus content by 60 %, neither plant growth nor the photosynthetic parameters were influenced by the addition of mineral nutrients. However, photosynthetic rates and growth of saplings decreased as the forest canopy became denser. Even when Amazonian soils are poor in nutrients, photosynthesis and sapling growth are more responsive to slight variations in light availability in the forest understory than to the availability of nutrients. Therefore, the response of saplings to future increases in atmospheric [CO2] will not be limited by the availability of mineral nutrients in the soil.

  5. Hydrological pulse regulating the bacterial heterotrophic metabolism between Amazonian mainstems and floodplain lakes

    Directory of Open Access Journals (Sweden)

    Luciana Oliveira Vidal

    2015-09-01

    Full Text Available We evaluated in situ rates of bacterial carbon processing in Amazonian floodplain lakes and mainstems, during both high and low water phases (p < 0.05. Our results showed that Bacterial Production (BP was lower and more variable than Bacterial Respiration (BR, determined as total respiration. Bacterial Carbon Demand (BCD was mostly accounted by BR and presented the same pattern that BR in both water phases. Bacterial growth efficiency showed a wide range (0.2–23% and low mean value of 3 and 6 %, (in high and low water respectively suggesting that dissolved organic carbon (DOC was mostly allocated to catabolic metabolism. However, BGE was regulated by BP in low water phase. Consequently, changes in BGE showed the same pattern that BP. In addition, the hydrological pulse effects on mainstems and floodplains lakes connectivity were found for BP and BGE in low water. Multiple correlation analyses revealed that indexes of organic matter quality (chlorophyll-a, N stable isotopes and C/N ratios were the strongest seasonal drivers of bacterial carbon metabolism. Our work indicated that: (1 the bacterial metabolism was mostly driven by respiration in Amazonian aquatic ecosystems resulting in low BGE in either high and low water phase; (2 the hydrological pulse regulated

  6. Disease concepts and treatment by tribal healers of an Amazonian forest culture.

    Science.gov (United States)

    Herndon, Christopher N; Uiterloo, Melvin; Uremaru, Amasina; Plotkin, Mark J; Emanuels-Smith, Gwendolyn; Jitan, Jeetendra

    2009-10-12

    The extensive medicinal plant knowledge of Amazonian tribal peoples is widely recognized in the scientific literature and celebrated in popular lore. Despite this broad interest, the ethnomedical systems and knowledge of disease which guide indigenous utilization of botanical diversity for healing remain poorly characterized and understood. No study, to our knowledge, has attempted to directly examine patterns of actual disease recognition and treatment by healers of an Amazonian indigenous culture. The establishment of traditional medicine clinics, operated and directed by elder tribal shamans in two remote Trio villages of the Suriname rainforest, presented a unique investigational opportunity. Quantitative analysis of clinic records from both villages permitted examination of diseases treated over a continuous period of four years. Cross-cultural comparative translations were articulated of recorded disease conditions through ethnographic interviews of elder Trio shamans and a comprehensive atlas of indigenous anatomical nomenclature was developed. 20,337 patient visits within the period 2000 to 2004 were analyzed. 75 disease conditions and 127 anatomical terms are presented. Trio concepts of disease and medical practices are broadly examined within the present and historical state of their culture. The findings of this investigation support the presence of a comprehensive and highly formalized ethnomedical institution within Trio culture with attendant health policy and conservation implications.

  7. Enzymes of energy metabolism in hatchlings of amazonian freshwater turtles (Testudines, Podocnemididae

    Directory of Open Access Journals (Sweden)

    WP. Duncan

    Full Text Available The metabolic profiles of selected tissues were analyzed in hatchlings of the Amazonian freshwater turtles Podocnemis expansa, P. unifilis and P. sextuberculata. Metabolic design in these species was judged based on the key enzymes of energy metabolism, with special emphasis on carbohydrate, lipid, amino acid and ketone body metabolism. All species showed a high glycolytic potential in all sampled tissues. Based on low levels of hexokinase, glycogen may be an important fuel for these species. The high lactate dehydrogenase activity in the liver may play a significant role in carbohydrate catabolism, possibly during diving. Oxidative metabolism in P. sextuberculata appears to be designed for the use of lipids, amino acids and ketone bodies. The maximal activities of 3-hydroxyacyl-CoA dehydrogenase, malate dehydrogenase, glutamine dehydrogenase, alanine aminotransferase and succinyl-CoA keto transferase display high aerobic potential, especially in muscle and liver tissues of this species. Although amino acids and ketone bodies may be important fuels for oxidative metabolism, carbohydrates and lipids are the major fuels used by P. expansa and P. unifilis. Our results are consistent with the food habits and lifestyle of Amazonian freshwater turtles. The metabolic design, based on enzyme activities, suggests that hatchlings of P. unifilis and P. expansa are predominately herbivorous, whereas P. sextuberculata rely on a mixed diet of animal matter and vegetation.

  8. Measurements of soil respiration and simple models dependent on moisture and temperature for an Amazonian southwest tropical forest

    NARCIS (Netherlands)

    Zanchi, F.B.; Rocha, Da H.R.; Freitas, De H.C.; Kruijt, B.; Waterloo, M.J.; Manzi, A.O.

    2009-01-01

    Soil respiration plays a significant role in the carbon cycle of Amazonian tropical forests, although in situ measurements have only been poorly reported and the dependence of soil moisture and soil temperature also weakly understood. This work investigates the temporal variability of soil respirati

  9. Heterogeneous effects of market integration on subadult body size and nutritional status among the Shuar of Amazonian Ecuador

    Science.gov (United States)

    Urlacher, Samuel S.; Liebert, Melissa A.; Snodgrass, J. Josh; Blackwell, Aaron D.; Cepon-Robins, Tara J.; Gildner, Theresa E.; Madimenos, Felicia C.; Amir, Dorsa; Bribiescas, Richard G.; Sugiyama, Lawrence S.

    2016-01-01

    Background Market integration (MI) – increasing production for and consumption from a market-based economy – is drastically altering traditional ways of life and environmental conditions among indigenous Amazonian peoples. The effects of MI on the biology and health of Amazonian children and adolescents, however, remain unclear. Aim This study examines the impact of MI on subadult body size and nutritional status at the population, regional, and household levels among the Shuar of Amazonian Ecuador. Subjects and Methods Anthropometric data were collected between 2005 and 2014 from 2,164 Shuar (age 2-19 years) living in two geographic regions differing in general degree of MI. High-resolution household economic, lifestyle, and dietary data were collected from a subsample of 631 participants. Analyses were performed to investigate relationships between body size and year of data collection, region, and specific aspects of household MI. Results Results from temporal and regional analyses suggest that MI has a significant and overall positive impact on Shuar body size and nutritional status. However, household-level results exhibit nuanced and heterogeneous specific effects of MI underlying these overarching relationships. Conclusion This study provides novel insight into the complex socio-ecological pathways linking MI, physical growth, and health among the Shuar and other indigenous Amazonian populations. PMID:27230632

  10. 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)

  11. Petrogenesis of the igneous Mucajaí AMG complex, northern Amazonian craton — Geochemical, U-Pb geochronological, and Nd-Hf-O isotopic constraints

    Science.gov (United States)

    Heinonen, A. P.; Fraga, L. M.; Rämö, O. T.; Dall'Agnol, R.; Mänttäri, I.; Andersen, T.

    2012-10-01

    The ca. 1525 Ma igneous Mucajaí anorthosite-monzonite-granite (AMG) complex in northern Brazil is a rare manifestation of Mesoproterozoic intraplate magmatism in the northern Amazonian Craton. The complex comprises a two-phase rapakivi granite batholith with subordinate quartz-fayalite monzonites and syenites and the closely associated Repartimento anorthosite. Zircon U-Pb (ID-TIMS) geochronology reveals that the anorthosite (1526 ± 2 Ma), monzonite (1526 ± 2 Ma), and the main-phase biotite-hornblende granite (1527 ± 2 Ma) of the complex intruded the Paleoproterozoic (~ 1.94 Ga) country rocks simultaneously at ~ 1526 Ma and that the more evolved biotite granite is marginally younger at 1519 ± 2 Ma. Intraplate magmatism in the Mucajaí region was relatively short-lived and lasted 12 million years (1529-1517 Ma) at maximum. The Nd (whole-rock, ID-TIMS; ɛNd from - 1.9 to - 2.8), Hf (zircon, LAM-ICP-MS; ɛHf from - 2.0 to - 3.1), and O (zircon, SIMS; δ18O from 6.1 to 7.0‰) isotopic compositions of the studied rocks are fairly uniform but still reveal a small degree of isotopic heterogeneity in the Paleoproterozoic crust enclosing the complex. The small isotopic differences observed in the two types of rapakivi granites (biotite-hornblende granite and biotite granite) may result either from an isotopically heterogeneous lower crustal source or, more likely, from contamination of the granitic magma derived from a lower crustal source during prolonged residence at upper crustal levels.

  12. Geology, petrology, U-Pb (SHRIMP) geochronology of the Morrinhos granite - Paragua terrane, SW Amazonian craton: implications for the magmatic evolution of the San Ignacio orogeny

    Energy Technology Data Exchange (ETDEWEB)

    Franca, Ohana; Ruiz, Amarildo Salina; Sousa, Maria Zelia Aguiar de, E-mail: ohana.geo@gmail.com, E-mail: asruiz@gmail.com, E-mail: mzaguiar@terra.com.br [Universidade Federal de Mato Grosso (UFMT), Cuiaba, MT (Brazil). Instituto de Ciencias Exatas e da Terra. Dept. de Geologia Geral; Batata, Maria Elisa Froes, E-mail: elisabatata@bol.com.br [Universidade Federal de Mato Grosso (UFMT), Cuiaba, MT (Brazil). Grupo de Pesquisa em Evolucao Crustal e Tectonica; Lafon, Jean-Michel [Universidade Federal do Para (GEOCIAM/UFPA), Belem, PR (Brazil). Inst. Nacional de Cencia e Tecnologia de Geociencias da Amazonia

    2014-09-15

    Morrinhos granite is a batholith body that is slightly elongated in the NNW direction and approximately 1,140 km{sup 2} long; it is located in the municipality of Vila Bela da Santissima Trindade of the state of Mato Grosso, Brazil, in the Paragua Terrane, Rondonian-San Ignacio Province, in the SW portion of the Amazonian Craton. This intrusion displays a compositional variation from tonalite to monzogranite, has a medium to coarse inequigranular texture and is locally porphyritic; biotite is the predominant mafic in one of the facies, and hornblende is predominant in the other, with both metamorphosed into the green schist facies. The studied rocks characterize an intermediate to acidic sequence that was formed by a subalkaline magmatism; the series is alkali-calcic to metaluminous to slightly peraluminous, and the rocks evolved through fractioned crystallization mechanisms. The structural data show two deformation phases represented by penetrative foliation (S{sub 1}) and open folds (D{sub 2}), and both phases were most likely related to the San Ignacio Orogeny. The geochronological (U-Pb SHRIMP) and isotopic (Sm-Nd) investigations of these rocks indicated a crystallization age of 1350±12Ma, T{sub DM} of approximately 1.77 Ga and εNd{sub (1.35}) with a negative value of -2.57, suggesting that their generation was related to a partial melting process of a Paleoproterozoic (Statherian) continental crust. The results herein indicate that the Morrinhos granite was generated in a continental magmatic arc in a late- to post-orogenic stage of the San Ignacio Orogeny, and it can be recognized as belonging to the Pensamiento Intrusive Suite. (author)

  13. The Effect of Aerosol-Cloud-Vegetation Interactions and Intraseasonal Meteorological Variability on Warm Cloud Development during the Amazonian Biomass Burning Season

    Science.gov (United States)

    Ten Hoeve, J. E.; Remer, L. A.; Jacobson, M. Z.

    2009-12-01

    The effect of aerosols on the hydrological cycle remains one of the largest uncertainties in our climate system. Biomass burning, from both deforestation and annual agricultural burning, is the largest anthropogenic source of these aerosols in the Southern Hemisphere. Biomass burning aerosols have competing effects on clouds: Depending on the level of aerosol loading and the background cloud characteristics, biomass burning aerosols have been shown in observational studies to invigorate or inhibit cloud formation and/or growth through microphysical and absorptive pathways, respectively. Many of these previous studies have employed all days during the Amazonian burning season months of August through October to formulate aerosol-cloud correlations, assuming relatively constant meteorological conditions exist throughout these months. This study investigates how intraseasonal trends of precipitable water vapor and aerosol loading between August and October impact these aerosol-cloud correlations. Other factors affecting aerosol-cloud relationships, such as atmospheric stability, are also investigated. This study is focused on a small 3 degree NE x 4 degree WE region in Rondonia, Brazil that encompasses extensive, contiguous areas of both forested and deforested land. High resolution aerosol, cloud, water vapor, and atmospheric profile data from the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra and Aqua satellites, as well as aerosol and water vapor data from the Aerosol Robotic Network (AERONET), are used collectively to explore the effect of aerosols on water vapor loading and warm cloud development over the Amazon. The difference in aerosol effects on the local hydrological cycle over forested and deforested areas is also examined. This final exercise provides insight into the relationship between aerosols, land-atmosphere processes, and warm clouds.

  14. Root niche separation can explain avoidance of seasonal drought stress and vulnerability of overstory trees to extended drought in a mature Amazonian forest

    Science.gov (United States)

    Ivanov, Valeriy Y.; Hutyra, Lucy R.; Wofsy, Steven C.; Munger, J. William; Saleska, Scott R.; de Oliveira, Raimundo C., Jr.; de Camargo, Plínio B.

    2012-12-01

    Large areas of Amazonian evergreen forest experience seasonal droughts extending for three or more months, yet show maximum rates of photosynthesis and evapotranspiration during dry intervals. This apparent resilience is belied by disproportionate mortality of the large trees in manipulations that reduce wet season rainfall, occurring after 2-3 years of treatment. The goal of this study is to characterize the mechanisms that produce these contrasting ecosystem responses. A mechanistic model is developed based on the ecohydrological framework of TIN (Triangulated Irregular Network)-based Real Time Integrated Basin Simulator + Vegetation Generator for Interactive Evolution (tRIBS+VEGGIE). The model is used to test the roles of deep roots and soil capillary flux to provide water to the forest during the dry season. Also examined is the importance of "root niche separation," in which roots of overstory trees extend to depth, where during the dry season they use water stored from wet season precipitation, while roots of understory trees are concentrated in shallow layers that access dry season precipitation directly. Observational data from the Tapajós National Forest, Brazil, were used as meteorological forcing and provided comprehensive observational constraints on the model. Results strongly suggest that deep roots with root niche separation adaptations explain both the observed resilience during seasonal drought and the vulnerability of canopy-dominant trees to extended deficits of wet season rainfall. These mechanisms appear to provide an adaptive strategy that enhances productivity of the largest trees in the face of their disproportionate heat loads and water demand in the dry season. A sensitivity analysis exploring how wet season rainfall affects the stability of the rainforest system is presented.

  15. Phylogenetic relationships of Amazonian anole lizards (Dactyloa): taxonomic implications, new insights about phenotypic evolution and the timing of diversification.

    Science.gov (United States)

    Prates, Ivan; Rodrigues, Miguel Trefaut; Melo-Sampaio, Paulo Roberto; Carnaval, Ana Carolina

    2015-01-01

    The ecology and evolution of Caribbean anoles are well described, yet little is known about mainland anole species. Lack of phylogenetic information limits our knowledge about species boundaries, morphological evolution, and the biogeography of anoles in South America. To help fill this gap, we provide an updated molecular phylogeny of the Dactyloa (Dactyloidae), with emphasis on the punctata species group. By sampling understudied Amazonian taxa, we (i) assess the phylogenetic placement of the 'odd anole', D. dissimilis; (ii) infer the relationships of the proboscis-bearing D. phyllorhina, testing the hypothesis of independent nasal appendage evolution within the anole radiation; and (iii) examine genetic and dewlap color variation in D. punctata and D. philopunctata. Combining multiple nuclear loci with a review of the fossil record, we also (iv) estimate divergence times within the pleurodont iguanian clade of lizards, including Amazonian representatives of Dactyloa and Norops (Dactyloidae) and of Polychrus (Polychrotidae). We recover the five Dactyloa clades previously referred to as the aequatorialis, heteroderma, latifrons, punctata and roquet species groups, as well as a sixth clade composed of D. dissimilis and the non-Amazonian D. neblinina and D. calimae. We find D. phyllorhina to be nested within the punctata group, suggesting independent evolution of the anole proboscis. We consistently recover D. philopunctata nested within D. punctata, and report limited genetic divergence between distinct dewlap phenotypes. The most recent common ancestor of Dactyloa, Anolis and Norops dates back to the Eocene. Most Amazonian taxa within both Dactyloa and Norops diverged in the Miocene, but some diversification events were as old as the late Eocene and late Oligocene. Amazonian Polychrus diverged in the Pliocene. Our findings have broad implications for anole biogeography, disputing recent suggestions that modern dactyloid genera were present in the Caribbean region

  16. Eastern Pacific Ocean Conference

    Science.gov (United States)

    The promotion of interaction among investigators of all oceanographic disciplines studying the eastern Pacific Ocean was the goal of the 1990 Eastern Pacific Ocean Conference (EPOC), held October 17-19 on the snow-covered slopes of Mt. Hood, Oreg. Thirty oceanographers representing all disciplines attended.Dick Barber, Duke University Marine Lab, Beaufort, N.C., chaired a session on the eastern equatorial Pacific Ocean, emphasizing issues related to biological activity. Steve Ramp of the Naval Postgraduate School in Montery, Calif., chaired a session on recent results from northern and central California experiments. On October 19, following an early morning earthquake, a business meeting and discussions regarding a collaboration in future experiments were held.

  17. Climatic Impact of the Bølling-Allerød over Eastern South America

    Science.gov (United States)

    Amorim Catunda, M. C.; Chiessi, C. M.; Strikis, N. M.; Mulitza, S.; Cruz, F. W., Sr.; Vuille, M. F.

    2015-12-01

    The last deglaciation was marked by large scale and rapid changes in rainfall over the tropics. Previous studies have correlated pulses of increased terrigenous input off semi arid northeastern South America with abrupt cold events in the high latitudes of the Northern Hemisphere. However, deglacial climate changes in other areas of South America are still not resolved. Here we reconstruct deglacial (23-11.5 cal ka BP) continental conditions over eastern Brazil based on (i) Ti/Ca of a radiocarbon dated marine sediment core as a proxy for Doce River (draining eastern Brazil) terrigenous input, and (ii) δ18O of a suite of U-Th dated stalagmites from eastern Brazil. Our marine core was recovered from 1100 m water depth on the tropical Brazilian continental slope, while our stalagmites come from Lapa Sem Fim cave. Both the Doce River and Lapa Sem Fim cave are located in the highly populated and economically active eastern Brazil, where most of the rainfall is related to the activity of the South America Monsoon System (SAMS). The Ti/Ca record is relatively stable showing high proportions of Ti in relationship to Ca throughout the deglacial, with a major excursion towards lower values indicating a decrease in terrigenous input synchronous to the Bølling-Allerød. Interestingly, speleothem δ18O also record this major excursion as less negative values. Together, our results suggest a major decrease in precipitation likely related to a weakening of the SAMS. We further compared our results with the output of the SYNTRACE run of CCSM3 fully coupled climate model with transient forcing for the last deglaciation. Geochemical records and model output show a very good coupling and suggest that the eastern Brazil experienced the driest period of the whole last deglaciation during the Bølling-Allerød and this dry spell was indeed related to a decreased SAMS intensity.

  18. Composição florística e a conservação de floresta secundárias na serra da Cantareira, São Paulo, Brasil. Floristic composition and conservation of old secondary Forest in the serra Cantareira in São Paulo, South-Eastern Brazil.

    Directory of Open Access Journals (Sweden)

    Frederico Alexandre Roccia Dal Pozzo ARZOLLA

    2011-06-01

    study was to describe the floristic composition of a stand of an old secondary forest in the Cantareira State Park in São Paulo, south-eastern Brazil. A total of approximately 11km of trail along the old and new power line routes were sampled between 2006 and 2010. A total of 179 species belonging to 54 families and 127 genera were identified in the floristic survey, with the richest families being Fabaceae (19 species, Myrtaceae (18, Lauraceae (16 and Rubiaceae (15 and the richest genera Ocotea and Myrcia (6, Eugenia (5 and Maytenus, Mollinedia and Nectandra with four species each. Ten of these species are considered threatened, four of them in the São Paulo state list and six in the IUCN list. One of these, Mollinedia oligotricha, was considered to be probably extinct. The floristic similarity with other forest remnants in the São Paulo Metropolitan Region and surrounding areas ranged from 11% to 38%. Threats to existing areas are discussed, together with possible conservation strategies.

  19. Variation in stem mortality rates determines patterns of above-ground biomass in Amazonian forests: implications for dynamic global vegetation models

    NARCIS (Netherlands)

    Johnson, Michelle O.; Galbraith, David; Gloor, Manuel; Deurwaerder, De Hannes; Guimberteau, Matthieu; Rammig, Anja; Thonicke, Kirsten; Verbeeck, Hans; Randow, Von Celso; Monteagudo, Abel; Phillips, Oliver L.; Brienen, Roel J.W.; Feldpausch, Ted R.; Lopez Gonzalez, Gabriela; Fauset, Sophie; Quesada, Carlos A.; Christoffersen, Bradley; Ciais, Philippe; Sampaio, Gilvan; Kruijt, Bart; Meir, Patrick; Moorcroft, Paul; Zhang, Ke; Alvarez-Davila, Esteban; Alves De Oliveira, Atila; Amaral, Ieda; Andrade, Ana; Aragao, Luiz E.O.C.; Araujo-Murakami, Alejandro; Arets, Eric J.M.M.; Arroyo, Luzmila; Aymard, Gerardo A.; Baraloto, Christopher; Barroso, Jocely; Bonal, Damien; Boot, Rene; Camargo, Jose; Chave, Jerome; Cogollo, Alvaro; Cornejo Valverde, Fernando; Lola Da Costa, Antonio C.; Fiore, Di Anthony; Ferreira, Leandro; Higuchi, Niro; Honorio, Euridice N.; Killeen, Tim J.; Laurance, Susan G.; Laurance, William F.; Licona, Juan; Lovejoy, Thomas; Malhi, Yadvinder; Marimon, Bia; Marimon, Ben Hur; Matos, Darley C.L.; Mendoza, Casimiro; Neill, David A.; Pardo, Guido; Peña-Claros, Marielos; Pitman, Nigel C.A.; Poorter, Lourens; Prieto, Adriana; Ramirez-Angulo, Hirma; Roopsind, Anand; Rudas, Agustin; Salomao, Rafael P.; Silveira, Marcos; Stropp, Juliana; Steege, Ter Hans; Terborgh, John; Thomas, Raquel; Toledo, Marisol; Torres-Lezama, Armando; Heijden, van der Geertje M.F.; Vasquez, Rodolfo; Guimarães Vieira, Ima Cèlia; Vilanova, Emilio; Vos, Vincent A.; Baker, Timothy R.

    2016-01-01

    Understanding the processes that determine aboveground biomass (AGB) in Amazonian forests is important for predicting the sensitivity of these ecosystems to environmental change and for designing and evaluating dynamic global vegetation models (DGVMs). AGB is determined by inputs from woody

  20. Cryptic patterns of diversification of a widespread Amazonian woodcreeper species complex (Aves: Dendrocolaptidae) inferred from multilocus phylogenetic analysis: implications for historical biogeography and taxonomy.

    Science.gov (United States)

    Sousa-Neves, Tiago; Aleixo, Alexandre; Sequeira, Fernando

    2013-09-01

    Inferring evolutionary relationships between recently diverged taxa is still challenging, especially taking into account the likely occurrence of incomplete lineage sorting and/or introgression. The Xiphorhynchus pardalotus/ocellatus species complex includes between two to three polytypic species and eight to nine subspecies distributed throughout most of lowland Amazonia and the foothills of the eastern Andes. To understand its historical diversification and address the main unsettled issues of phylogenetic relationships and taxonomy, we apply several approaches using data from two mitochondrial (Cyt b and ND2) and three nuclear genes (β-fibint7, CPZint3 and CRYAAint1) for all described species and most subspecies of this complex. We compared single gene trees with a multilocus concatenated tree and Bayesian species tree inferred under a coalescent framework ((*)BEAST). Our results showed a general pattern of incongruence among gene trees and multilocus trees. Despite of this, the coalescent-based species tree analysis supports the sister-taxa relationship of X. ocellatus and X. chunchotambo, while X. pardalotus comes out as the basal taxon. With exception of the last, our results revealed within both X. ocellatus and X. chunchotambo high levels of genetic differentiation (p-distances 0.5-5.5%) with well-supported lineages. Our phylogenetic analyses showed several incongruences with current subspecies taxonomy, revealing that X. o. ocellatus is paraphyletic relative to X. o. perplexus, and the currently recognized subspecies X. c. napensis corresponds to two distinct evolutionary lineages, which are not supported as sister-lineages. In addition, the deep level of genetic divergence between X. o. beauperthuysii and the extant subspecies of X. ocellatus is more consistent with species-level differences found in this complex. Divergence time estimates were consistent with a historical scenario of intense population subdivision and speciation during the Early

  1. Aqueous Alteration at a Delta in Eastern Libya Montes

    Science.gov (United States)

    Bishop, Janice L.; Tirsch, Daniela; Tornabene, Livio L.; Seelos, Frank P.; Erkeling, Gino; Hiesinger, Harald; Jaumann, Ralf

    2015-04-01

    Libya Montes hosts ancient Noachian basalt altered by hydrothermal action from the Isidis impact, olivine- and pyroxene-bearing lavas from the Syrtis volcanic outflows, multiple craters that have excavated these geologic units, and numerous Hesperian-Amazonian-aged fluvial features that carved channels across the surface and may have transported material downward towards Isidis. Mineralogical analyses of a delta region in Eastern Libya Montes using recently available MTR3 CRISM images have revealed the presence of carbonate in additional to Al-, Fe-, and Mg-bearing phyllosilicates. We are investigating the origins of these aqueous components through stratigraphical and morphological analyses. We hypothesize that the carbonate and Fe/Mg-phyllosilicates are alteration products of the ancient basalt and that the Al-smectite formed as a result of the delta and more recent lacustrine or fluvial processes. The Al-smectite spectral features are most consistent with beidellite, which forms at elevated temperatures compared to montmorillonite. We seek to determine if the beidellite likely formed in warm delta waters or if it may have formed via burial diagenesis and was then excavated by the delta. Newly developed CRISM parameters are being utilized for analysis of the MTR3 versions of CRISM images FRT0000B0CB and FRT0001E2F2 in the fan and delta region of eastern Libya Montes. The MTR3 images feature joined short-wavelength and long-wavelength images and improved spectral signals through new atmospheric separation and noise removal techniques. This enables better detection of spectral signatures from small outcrops of aqueous components. We have placed these new CRISM mineral maps over HRSC stereo images to evaluate the stratigraphy of the aqueous components in relation to the ancient basalt and Syrtis lavas as in previous analyses of the central Libya Montes region. Coordinated CRISM-HiRISE views are expected to provide insights into the morphologies of the aqueous units

  2. Two hundred years of local avian extinctions in eastern Amazonia.

    Science.gov (United States)

    Moura, Nárgila G; Lees, Alexander C; Aleixo, Alexandre; Barlow, Jos; Dantas, Sidnei M; Ferreira, Joice; Lima, Maria de Fátima C; Gardner, Toby A

    2014-10-01

    Local, regional, and global extinctions caused by habitat loss, degradation, and fragmentation have been widely reported for the tropics. The patterns and drivers of this loss of species are now increasingly well known in Amazonia, but there remains a significant gap in understanding of long-term trends in species persistence and extinction in anthropogenic landscapes. Such a historical perspective is critical for understanding the status and trends of extant biodiversity as well as for identifying priorities to halt further losses. Using extensive historical data sets of specimen records and results of contemporary surveys, we searched for evidence of local extinctions of a terra firma rainforest avifauna over 200 years in a 2500 km(2) eastern Amazonian region around the Brazilian city of Belém. This region has the longest history of ornithological fieldwork in the entire Amazon basin and lies in the highly threatened Belém Centre of Endemism. We also compared our historically inferred extinction events with extensive data on species occurrences in a sample of catchments in a nearby municipality (Paragominas) that encompass a gradient of past forest loss. We found evidence for the possible extinction of 47 species (14% of the regional species pool) that were unreported from 1980 to 2013 (80% last recorded between 1900 and 1980). Seventeen species appear on the International Union for Conservation of Nature Red List, and many of these are large-bodied. The species lost from the region immediately around Belém are similar to those which are currently restricted to well-forested catchments in Paragominas. Although we anticipate the future rediscovery or recolonization of some species inferred to be extinct by our calculations, we also expect that there are likely to be additional local extinctions, not reported here, given the ongoing loss and degradation of remaining areas of native vegetation across eastern Amazonia.

  3. Abelhas-sem-ferrão amazônicas defendem meliponários contra saques de outras abelhas Amazonian stingless bees protect meliponaries against robber bees

    Directory of Open Access Journals (Sweden)

    André Rodrigo Rech

    2013-09-01

    Full Text Available Entre as abelhas eussociais, dois gêneros apresentam estratégia de vida cleptobiótica, obtendo recursos alimentares de ninhos de outras abelhas ao invés de coletá-los em flores. Entre as espécies atacadas existe um gradiente de suscetibilidade ao roubo variando desde espécies vulneráveis até altamente resistentes. Neste trabalho nós descrevemos um ataque de Lestrimelitta rufipes a um ninho de Scaptotrigona sp. em um meliponário na Amazônia central (Amazonas, Brazil. O ninho atacado foi transferido para um meliponário com espécies resistentes (Duckeola ghilianii e Melipona fulva e as interações foram descritas. As abelhas resistentes contra-atacaram e afugentaram as ladras protegendo o ninho de Scaptotrigona sp.. A presença de comportamento defensivo em gêneros não proximamente relacionados sugere que ele tenha evoluído mais de uma vez entre os Meliponini. Considerando o comportamento descrito, sugerimos a criação de espécies nativas resistentes em meliponários de regiões onde elas forem nativas, devido ao potencial que elas tem na proteção.Among eusocial bees, two genera evolved a cleptobiotic life strategy, stealing food resources from other bee nest instead of collecting it from flowers. Under natural conditions there is a gradient of strategies against robbing, from more susceptible to highly resistant species. In this work, we describe one attack of the robber bee Lestrimelitta rufipes to a nest of Scaptotrigona sp. in the Amazon Rain Forest (Amazonas, Brazil. The attacked nest was introduced in a beekeeping area with bees already known to be resistant to cleptobiosis. The resident bees (Duckeola ghilianii and Melipona fulva counter-attacked the robber bees and successfully protect the Scaptotrigona sp. nest. The presence of the defensive behaviour in unrelated genera suggests it evolved many times in social bees. Based on the protective behaviour described here, we suggest that in order to reduce the damage caused

  4. A new species of Tmesiphantes (Araneae, Theraphosidae from the state of Pará, Brazil

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    Hector M. O. Gonzalez-Filho

    2014-06-01

    Full Text Available A new species of Tmesiphantes Simon, 1892, T. aridai sp. nov., is described and illustrated based on three males and three females collected at the Floresta Nacional do Tapajós, Santarém, state of Pará, Brazil. Males can be distinguished from T. perp Guadanucci & Silva, 2012 by the palpal bulb with an inconspicous tegular basal projection, but presenting a very slender embolus with shorter keels not extending to the tip, and from T. nubilus Simon, 1892 by the tibial apophysis with two similarly sized branches, the prolateral one with a strong spine on the retrolateral margin. Females resemble T. nubilus by the aspect of the seminal receptacle but the constriction near the apex is less evident and apex shape is irregular. The new species represents the first record of Tmesiphantes from the Amazonian region, bringing the total number of species to eight.

  5. Do Hydroelectric Dams Mitigate Global Warming? The Case of Brazil's Curuna Dam

    Energy Technology Data Exchange (ETDEWEB)

    Fearnside, P.M. [National Institute for Research in the Amazon (INPA), C.P. 478, 69011-970 Manaus, Amazonas (Brazil)

    2005-10-15

    Hydroelectric dams in tropical forest areas emit greenhouse gases, as illustrated by the Curuna dam in the Amazonian portion of Brazil. Emissions include carbon dioxide from decay of the above-water portions of trees that are left standing in the reservoir and methane from soft vegetation that decays under anaerobic conditions on the bottom of the reservoir, especially macrophytes (water weeds) and vegetation that grows in the drawdown zone and is flooded when the reservoir water level rises. Some methane is released from the reservoir surface through bubbling and diffusion, but larger amounts are released from water passing through the turbines and spillway. Methane concentration in the water increases with depth, and the turbines and spillway draw water from sufficient depth to have substantial methane content. In 1990 (13 years after filling), the Curuna Dam emitted 3.6 times more greenhouse gases than would have been emitted by generating the same amount of electricity from oil.

  6. State, socioenvironmental conflict and violence in the Amazon border of Brazil, Colombia and Perú

    Directory of Open Access Journals (Sweden)

    Carlos Gilberto Zárate Botía

    2017-07-01

    Full Text Available The Amazonian border region of Brazil, Colombia and Peru has been place or stage to extraction, trade and transport of a wide variety of forest and aquatic resources, including those associated with activities considered illegal like drug or some types of mining. Aditionally the borders have also been converted in areas of conflict, violence and insecurity, and these, at the same time, are produced and exacerbated by state and institutional weakness of the three states, trying substitute it increasing the military presence, with little and contested results, on the one hand, by different public policies or the existence of rules and laws also different and incompatible. In a historical and current perspective, the article shows the relationship between the state, extractive economies of natural resources and conflict in the brazilian, colombian and peruvian amazon border, taking into account the limitations and possibilities of agreements recently signed between the government Colombian Juan Manuel Santos and FARC guerrillas.

  7. Contemporary Guarani Shamanisms: “Traditional Medicine” and Discourses of Native Identity in Brazil

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    E J Langdon

    2012-09-01

    Full Text Available The psychoactive substance known as ayahuasca has long been identified with Amazonian shamanism and traditional medicine. Over the last two decades its use has spread outside this region to urban populations in different parts of the world. This paper examines the adoption of the ritual use of the beverage by the Guarani Indians along the southern coast of Brazil. We argue that this process is related to the growing politics of identity of Brazilian indigenous peoples as well as to public policies that promote cultural diversity. In the case analyzed here, the adoption of ayahuasca is articulated with an ongoing cultural revitalization in activities related to shamanism, health and education and with the specific desires and actions of the leading family in one Guarani village.

  8. Above- and below-ground net primary productivity across ten Amazonian forests on contrasting soils

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    L. E. O. C. Aragão

    2009-12-01

    Full Text Available The net primary productivity (NPP of tropical forests is one of the most important and least quantified components of the global carbon cycle. Most relevant studies have focused particularly on the quantification of the above-ground coarse wood productivity, and little is known about the carbon fluxes involved in other elements of the NPP, the partitioning of total NPP between its above- and below-ground components and the main environmental drivers of these patterns. In this study we quantify the above- and below-ground NPP of ten Amazonian forests to address two questions: (1 How do Amazonian forests allocate productivity among its above- and below-ground components? (2 How do soil and leaf nutrient status and soil texture affect the productivity of Amazonian forests? Using a standardized methodology to measure the major elements of productivity, we show that NPP varies between 9.3±1.3 Mg C ha−1 yr−1 (mean±standard error, at a white sand plot, and 17.0±1.4 Mg C ha−1 yr−1 at a very fertile Terra Preta site, with an overall average of 12.8±0.9 Mg C ha−1 yr−1. The studied forests allocate on average 64±3% and 36±3% of the total NPP to the above- and below-ground components, respectively. The ratio of above-ground and below-ground NPP is almost invariant with total NPP. Litterfall and fine root production both increase with total NPP, while stem production shows no overall trend. Total NPP tends to increase with soil phosphorus and leaf nitrogen status. However, allocation of NPP to below-ground shows no relationship to soil fertility, but appears to decrease with the increase of soil clay content.

  9. Above- and below-ground net primary productivity across ten Amazonian forests on contrasting soils

    Directory of Open Access Journals (Sweden)

    L. E. O. C. Aragão

    2009-02-01

    Full Text Available The net primary productivity (NPP of tropical forests is one of the most important and least quantified components of the global carbon cycle. Most relevant studies have focused particularly on the quantification of the above-ground coarse wood productivity, and little is known about the carbon fluxes involved in other elements of the NPP, the partitioning of total NPP between its above- and below-ground components and the main environmental drivers of these patterns. In this study we quantify the above- and below-ground NPP of ten Amazonian forests to address two questions: (1 How do Amazonian forests allocate productivity among its above- and below-ground components? (2 How do soil and leaf nutrient status and soil texture affect the productivity of Amazonian forests? Using a standardized methodology to measure the major elements of productivity, we show that NPP varies between 9.3±1.3 Mg C ha−1 yr−1 (mean±standard error, at a white sand plot, and 17.0±1.4 Mg C ha−1 yr−1 at a very fertile Terra Preta site, with an overall average of 12.8±0.9 Mg C ha−1 yr−1. The studied forests allocate on average 64±3% and 36±3% of the total NPP to the above- and below-ground components, respectively. The ratio of above-ground and below-ground NPP is almost invariant with total NPP. Litterfall and fine root production both increase with total NPP, while stem production shows no overall trend. Total NPP tends to increase with soil phosphorus and leaf nitrogen status. However, allocation of NPP to below-ground shows no relationship to soil fertility, but appears to decrease with the increase of soil clay content.

  10. Epidemiological aspects of astrovirus and coronavirus in poults in the South Eastern Region of Brazil Aspectos epidemiológicos associados à prevalência de Astrovirus e Coronavirus em lotes de perus da Região Sudeste do Brasil

    Directory of Open Access Journals (Sweden)

    S.E.L. da Silva

    2009-06-01

    Full Text Available A survey of Turkey Coronavirus (TCoV and Astrovirus (TAstV-2 prevalence was carried out from February to December during 2006 year in semiarid region of Brazil, from a turkey producer area, localized in South Eastern of Brazil. To asses the risk factor related to clinical material, climatic condition and type of RT-PCR applied, cloacal swabs (CS, faeces, sera, bursa of Fabricius (BF, thymus (TH and spleen (SP and ileum-caeca region were collected from 30-day-old poults suffering of enteritis episode characterized as poult enteritis mortality syndrome (PEMS. The PEMS clinical features were characterized by watery to foamy faeces, light brown-yellow in colour and low mortality rate. Meteorological data (rainfall and relative humidity observed during along the study presented monthly average temperature ranging from 39.3 and 31.2ºC, precipitation in rainy season from 40 to 270.3 mm/month, and no rain during dry season. Simplex RT-PCR gave odds ratio (OR values suggesting that ileum-caeca region is at higher chance (OR=1.9; p=0.9741 to have both viral RNA than faeces (OR=1.5; p=0.7319. However, multiplex RT-PCR showed 3.98 (p=0.89982 more chance to give positive results in faeces than CS at dry season. The major risk factors seem to be low rate of humidity and high temperatures at winter, probably responsible for spread, easily, the TCoV and TAstv-2 among the flocks. The positive results of both virus suggested that they can play an important role in enteric disorders, associated to low humidity and high temperatures frequently found in tropical countries.O presente estudo foi conduzido para avaliar a prevalência do Coronavirus dos perus (TCoV e Astrovirus tipo 2 (TAstV-2 entre os meses de Fevereiro a Dezembro de 2006, em uma região produtora localizada no semi-árido a Sudeste do Brasil. Os principais fatores de risco associado a prevalência foram material clínico analisado, condições climáticas e tipo de técnica molecular empregada. Os

  11. DISCOVERING BEIJING Eastern Promise

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Dongcheng District, literally meaning eastern city, covers Beijing’s downtown area to the northeast of the central axis of old Beijing. The district has a total area of 25 square km and a population of 600,000. With a large number of cultural and historical sites and tourist attractions,

  12. Eastern Spruce Dwarf Mistletoe

    Science.gov (United States)

    F. Baker; Joseph O' Brien; R. Mathiasen; Mike Ostry

    2006-01-01

    Eastern spruce dwarf mistletoe (Arceuthobium pusillum) is a parasitic flowering plant that causes the most serious disease of black spruce (Picea mariana) throughout its range. The parasite occurs in the Canadian provinces of Saskatchewan, Manitoba, Ontario, Quebec, New Brunswick, Nova Scotia, Prince Edward Island, and Newfoundland; in the Lake States of Minnesota,...

  13. Eastern Frequency Response Study

    Energy Technology Data Exchange (ETDEWEB)

    Miller, N.W.; Shao, M.; Pajic, S.; D' Aquila, R.

    2013-05-01

    This study was specifically designed to investigate the frequency response of the Eastern Interconnection that results from large loss-of-generation events of the type targeted by the North American Electric Reliability Corp. Standard BAL-003 Frequency Response and Frequency Bias Setting (NERC 2012a), under possible future system conditions with high levels of wind generation.

  14. Carbon recovery dynamics following disturbance by selective logging in Amazonian forests.

    Science.gov (United States)

    Piponiot, Camille; Sist, Plinio; Mazzei, Lucas; Peña-Claros, Marielos; Putz, Francis E; Rutishauser, Ervan; Shenkin, Alexander; Ascarrunz, Nataly; de Azevedo, Celso P; Baraloto, Christopher; França, Mabiane; Guedes, Marcelino; Honorio Coronado, Eurídice N; d'Oliveira, Marcus Vn; Ruschel, Ademir R; da Silva, Kátia E; Doff Sotta, Eleneide; de Souza, Cintia R; Vidal, Edson; West, Thales Ap; Hérault, Bruno

    2016-12-20

    When 2 Mha of Amazonian forests are disturbed by selective logging each year, more than 90 Tg of carbon (C) is emitted to the atmosphere. Emissions are then counterbalanced by forest regrowth. With an original modelling approach, calibrated on a network of 133 permanent forest plots (175 ha total) across Amazonia, we link regional differences in climate, soil and initial biomass with survivors' and recruits' C fluxes to provide Amazon-wide predictions of post-logging C recovery. We show that net aboveground C recovery over 10 years is higher in the Guiana Shield and in the west (21 ±3 Mg C ha-1) than in the south (12 ±3 Mg C ha-1) where environmental stress is high (low rainfall, high seasonality). We highlight the key role of survivors in the forest regrowth and elaborate a comprehensive map of post-disturbance C recovery potential in Amazonia.

  15. Bioactive properties of Tynanthus panurensis (Bureau) Sanwith bark extract, the Amazonian "clavo huasca".

    Science.gov (United States)

    Morales, Lidia; Acero, Nuria; Galán, Antonio; Perez-García, Carmen; Alguacil, Luis Fernando; Muñoz-Mingarro, Dolores

    2011-09-01

    Tynanthus panurensis (Bureau) Sanwith (Bignoniaceae) is a liana vine used in traditional Amazonian medicine as a tonic and energizer as well as a treatment for rheumatism. These traditional indications prompted this study of the antioxidant and anti-inflammatory activities of T. panurensis bark extract (ETP). Phytochemical analysis of ETP showed the presence of saponins and a high concentration of phenols and flavonoids. A battery of in vitro tests revealed that the extract has free radical-scavenging antioxidant properties and reduces microsomal lipid peroxidation, uric acid synthesis, and tumor necrosis factor-α production. The anti-inflammatory properties of ETP were further confirmed in vivo in a rat carrageenan edema model, in which the extract exhibited a potent activity. These results support the idea that T. panurensis bark extract could be beneficial for treating inflammation and are in agreement with one of the main traditional uses of this plant.

  16. Securitization, alterity, and the state Human (in)security on an Amazonian frontier.

    Science.gov (United States)

    Brightman, Marc; Grotti, Vanessa

    2014-12-01

    Focusing on the region surrounding the Maroni River, which forms the border between Suriname and French Guiana, we examine how relations between different state and non-state social groups are articulated in terms of security. The region is characterised by multiple "borders" and frontiers of various kinds, the state boundary having the features of an interface or contact zone. Several key collectivities meet in this border zone: native Amazonians, tribal Maroon peoples, migrant Brazilian gold prospectors, and metropolitan French state functionaries. We explore the relationships between these different sets of actors and describe how their mutual encounters center on discourses of human and state security, thus challenging the commonly held view of the region as a stateless zone and showing that the "human security" of citizens from the perspective of the state may compete with locally salient ideas or experiences of well-being.

  17. Qualitative assessment of visuospatial errors in mercury-exposed Amazonian children

    DEFF Research Database (Denmark)

    Chevrier, Cécile; Sullivan, Kimberly; White, Roberta F.;

    2009-01-01

    In order to better define the effects of methylmercury (MeHg) exposure on neurodevelopment, qualitative error types observed in the responses of exposed children to the Stanford-Binet Copying Test were categorized and quantified using raw data from two studies of 395 Amazonian children aged 7...... with adjustment for confounders. In the combined data set, mercury exposure was negatively associated with scores on the drawing task: a score reduction of 1.2 (s.e., 0.3) points was observed in the children with a hair-mercury concentration above 10 μg/g compared to those with a hair level below 1 μg....../g; this effect appeared to be stronger in the younger children. Risk of committing one or more errors of rotation, simplification or perseveration in the drawings increased with hair-mercury concentration in both cultural settings, providing convergent evidence of specific types of MeHg-related neurocognitive...

  18. Potential application in biocatalysis of mycelium-bound lipases from Amazonian fungi

    Energy Technology Data Exchange (ETDEWEB)

    Zanotto, Sandra P.; Romano, Israel P.; Lisboa, Lilian U.S.; Duvoisin Junior, Sergio; Lima, Fabiana A.; Silva, Soraya F.; Alburquerque, Patricia M. [Universidade Federal do Amazonas (UFAM), Manaus, AM (Brazil). Programa em Biotecnologia e Recursos Naturais da Amazonia. Lab. de Biorganica; Martins, Mayra K. [Centro de Biotecnologia do Amazonas, Manaus, AM (Brazil)

    2009-07-01

    In this study, 212 fungi were isolated from Amazon region plants, aiming to obtain mycelium bound-lipase-producing biocatalysts. These isolates were submitted to hydrolytic and synthetic activity assays. When submitted to the tributyrine substrate test, 87% of the isolates showed hydrolytic activity. Of these, 30% showed good growth in lipase inducing liquid media and were submitted to evaluation of synthetic activity in esterification and transesterification reactions in organic solvents. The nine fungi which had the best synthetic activity were evaluated in the (R, S)-2-octanol resolution reaction, in order to verify the enantioselectivity of mycelium-bound lipases. The isolate UEA{sub 1}15 was the most versatile biocatalyst, showing good performance in esterification reactions (conversion > 90%) and good ability for the resolution of (R, S)-2-octanol (ees 29%; eep 99%; c 22%; E > 200). Thus, this study has demonstrated the great potential of the Amazonian fungi as lipase suppliers for biocatalysts.(author)

  19. Elemental mercury in the atmosphere of a tropical Amazonian forest (French Guiana)

    Energy Technology Data Exchange (ETDEWEB)

    Amouroux, D.; Wasserman, J.C.Tessier, E.; Donard, O.F.X. [Univ. de Pau et des Pays de l`Adour, Pau (France). Lab. de Chimie Analytique Bio-Inorganique et Environnement

    1999-09-01

    Gaseous atmospheric mercury was investigated at two sites of a tropical Amazonian forest (French Guiana) in the Petit Inini River basin and the Petit Saut Lake in June, 1998. Gaseous atmospheric mercury was identified as elemental mercury (Hg{sup 0}). Diurnal variation of atmospheric Hg{sup 0} in both studied aquatic environments were significantly correlated with air temperature and anticorrelated with relative humidity. Average Hg{sup 0} concentrations were higher above the Petit Inini River that the Petit Saut Lake. Background Hg{sup 0} concentrations in the Petit Inini River basin were higher than those observed in remote environments. These data suggest that gold mining activity (i.e., Petit Inini River basin) may influence mercury mobilization in tropical forest ecosystems and that atmospheric transfer is a major pathway for mercury cycling in these environments.

  20. Phylogenetic origins of local-scale diversity patterns and the causes of Amazonian megadiversity.

    Science.gov (United States)

    Wiens, John J; Pyron, R Alexander; Moen, Daniel S

    2011-07-01

    What explains the striking variation in local species richness across the globe and the remarkable diversity of rainforest sites in Amazonia? Here, we apply a novel phylogenetic approach to these questions, using treefrogs (Hylidae) as a model system. Hylids show dramatic variation in local richness globally and incredible local diversity in Amazonia. We find that variation in local richness is not explained primarily by climatic factors, rates of diversification (speciation and extinction) nor morphological variation. Instead, local richness patterns are explained predominantly by the timing of colonization of each region, and Amazonian megadiversity is linked to the long-term sympatry of multiple clades in that region. Our results also suggest intriguing interactions between clade diversification, trait evolution and the accumulation of local richness. Specifically, sympatry between clades seems to slow diversification and trait evolution, but prevents neither the accumulation of local richness over time nor the co-occurrence of similar species.

  1. A decade of malaria during pregnancy in Brazil: what has been done concerning prevention and management

    Directory of Open Access Journals (Sweden)

    Paola Marchesini

    2014-08-01

    Full Text Available In Brazil, malaria remains a disease of major epidemiological importance because of the high number of cases in the Amazonian Region. Plasmodium spp infections during pregnancy are a significant public health problem with substantial risks for the pregnant woman, the foetus and the newborn child. In Brazil, the control of malaria during pregnancy is primarily achieved by prompt and effective treatment of the acute episodes. Thus, to assure rapid diagnosis and treatment for pregnant women with malaria, one of the recommended strategy for low transmission areas by World Health Organization and as part of a strategy by the Ministry of Health, the National Malaria Control Program has focused on integrative measures with woman and reproductive health. Here, we discuss the approach for the prevention and management of malaria during pregnancy in Brazil over the last 10 years (2003-2012 using morbidity data from Malaria Health Information System. Improving the efficiency and quality of healthcare and education and the consolidation of prevention programmes will be challenges in the control of malaria during pregnancy in the next decade.

  2. A decade of malaria during pregnancy in Brazil: what has been done concerning prevention and management.

    Science.gov (United States)

    Marchesini, Paola; Costa, Fabio Trindade Maranhão; Marinho, Claudio Romero Farias

    2014-08-01

    In Brazil, malaria remains a disease of major epidemiological importance because of the high number of cases in the Amazonian Region. Plasmodium spp infections during pregnancy are a significant public health problem with substantial risks for the pregnant woman, the foetus and the newborn child. In Brazil, the control of malaria during pregnancy is primarily achieved by prompt and effective treatment of the acute episodes. Thus, to assure rapid diagnosis and treatment for pregnant women with malaria, one of the recommended strategy for low transmission areas by World Health Organization and as part of a strategy by the Ministry of Health, the National Malaria Control Program has focused on integrative measures with woman and reproductive health. Here, we discuss the approach for the prevention and management of malaria during pregnancy in Brazil over the last 10 years (2003-2012) using morbidity data from Malaria Health Information System. Improving the efficiency and quality of healthcare and education and the consolidation of prevention programmes will be challenges in the control of malaria during pregnancy in the next decade.

  3. Late Quaternary vegetational and climate dynamics in northeastern Brazil, inferences from marine core GeoB 3104-1

    Science.gov (United States)

    Behling, Hermann; W. Arz, Helge; Pätzold, Jürgen; Wefer, Gerold

    2000-06-01

    Late Quaternary paleoenvironments from northeastern (NE) Brazil have been studied by pollen analysis of marine sediment. The studied core GeoB 3104-1 (3°40' S, 37°43' W, 767 m b.s.l.) from the upper continental slope off NE Brazil is 517 cm long and >42,000 14C yr BP old. Chronological control was obtained by 12 radiocarbon (AMS) dates from individuals of the foraminiferal species Globigerinoides sacculifer. Modern pollen analogs were received from 15 river, lake and forest soil surface samples from NE Brazil. Marine pollen dates indicate the predominance of semi-arid caatinga vegetation in NE Brazil during the recorded period between >42,000 and 8500 14C yr BP. The increased fluvial input of terrigenous material, with high concentrations of pollen and specially fern spores, into the marine deposits, about 40,000, 33,000 and 24,000 14C yr BP and between 15,500 and 11,800 14C yr BP, indicate short-term periods of strong rainfall on the NE Brazilian continent. The expansion of mountain, floodplain and gallery forests characterize the interval between 15,500 and 11,800 14C yr BP as the wettest recorded period in NE Brazil, which allowed floristic exchanges between Atlantic rain forest and Amazonian rain forest, and vice versa. The paleodata from core GeoB 3104-1 confirm the, in general, dry pre-Last Glacial Maximum (LGM) and LGM conditions and the change to wet Lateglacial environments in tropical South America. The annual movement of the intertropical convergence zone over NE Brazil, the strong influence of the Antarctic cold fronts and changes of the high-pressure cell over the southern Atlantic, may explain the very wet Lateglacial period in NE Brazil. The documented NE Brazilian short-term signals correlate with the documented Dansgaard-Oeschger cycles and Heinrich events from the northern Hemisphere and suggest strong teleconnections.

  4. Recent (Late Amazonian) enhanced backweathering rates on Mars: Paracratering evidence from gully alcoves

    Science.gov (United States)

    de Haas, Tjalling; Conway, Susan; Krautblatter, Michael

    2016-04-01

    Mars is believed to have been exposed to low planet-wide weathering and denudation since the Noachian period (˜4.1 - 3.7 Ga). However, the widespread occurrence of alcoves at the rim of pristine impact craters suggests locally enhanced recent backweathering rates. Here we derive Late Amazonian backweathering rates from the alcoves of 10 young equatorial and mid-latitude craters, ranging in age from 0.2 to 45 Ma. The enhanced Late Amazonian Martian backweathering rates (10-4 - 10-1 mm yr-1) are approximately one order of magnitude higher than previously reported erosion rates, and are similar to terrestrial rates inferred from Meteor crater and various Arctic and Alpine rock faces, when corrected for age. Alcoves on initially highly fractured and oversteepened crater rims following impact show enhanced backweathering rates that decline over at least 101 - 102 Myr as the crater wall stabilizes. This 'paracratering' backweathering decline with time is analogous to the paraglacial effect observed in rock slopes after deglaciation, but the relaxation time scale of 101 - 102 Myr compared to 10 kyr of the Milankovitch-controlled interglacial duration questions whether a paraglacial steady state is reached on Earth. The backweathering rates on the gullied pole-facing alcoves of the studied mid-latitude craters are much higher (˜2 - 60 times) than those on slopes with other azimuths and those in equatorial craters. The enhanced backweathering rates on gullied crater slopes may result from liquid water acting as a catalyst for backweathering. The decrease in backweathering rates over time might explain the similar size of gullies in young (craters, as alcove growth and sediment supply decrease to low background rates over time.

  5. The role of Amazonian anthropogenic soils in shifting cultivation: learning from farmers' rationales

    Directory of Open Access Journals (Sweden)

    André B. Junqueira

    2016-03-01

    Full Text Available We evaluated farmers' rationales to understand their decision making in relation to the use of fertile anthropogenic soils, i.e., Amazonian dark earths (ADE, and for dealing with changes in shifting cultivation in Central Amazonia. We analyzed qualitative information from 196 interviews with farmers in 21 riverine villages along the Madeira River. In order to decide about crop management options to attain their livelihood objectives, farmers rely on an integrated and dynamic understanding of their biophysical and social environment. Farmers associate fallow development with higher crop yields and lower weed pressure, but ADE is always associated with high yields and high weeding requirements. Amazonian dark earths are also seen as an opportunity to grow different crops and/or grow crops in more intensified management systems. However, farmers often maintain simultaneously intensive swiddens on ADE and extensive swiddens on nonanthropogenic soils. Farmers acknowledge numerous changes in their socioeconomic environment that affect their shifting cultivation systems, particularly their growing interaction with market economies and the incorporation of modern agricultural practices. Farmers considered that shifting cultivation systems on ADE tend to be more prone to changes leading to intensification, and we identified cases, e.g., swiddens used for watermelon cultivation, in which market demand led to overintensification and resulted in ADE degradation. This shows that increasing intensification can be a potential threat to ADE and can undermine the importance of these soils for agricultural production, for the conservation of agrobiodiversity, and for local livelihoods. Given that farmers have an integrated knowledge of their context and respond to socioeconomic and agro-ecological changes in their environment, we argue that understanding farmers' knowledge and rationales is crucial to identify sustainable pathways for the future of ADE and of

  6. A Molecular Survey of the Diversity of Microbial Communities in Different Amazonian Agricultural Model Systems

    Directory of Open Access Journals (Sweden)

    Acácio A. Navarrete

    2010-05-01

    Full Text Available The processes of land conversion and agricultural intensification are a significant cause of biodiversity loss, with consequent negative effects both on the environment and the sustainability of food production.The anthrosols associated with pre-Colombian settlements in the Amazonian region are examples of how anthropogenic activities may sustain the native populations against harsh tropical environments for human establishment, even without a previous intentionality of anthropic soil formation. In a case study (Model I—“Slash-and-Burn” the community structures detected by automated ribosomal intergenic spacer analysis (ARISA revealed that soil archaeal, bacterial and fungal communities are heterogeneous and each capable of responding differently to environmental characteristics. ARISA data evidenced considerable difference in structure existing between microbial communities in forest and agricultural soils. In a second study (Model II—“Anthropogenic Soil”, the bacterial community structures revealed by terminal restriction fragment length polymorphism (T-RFLP differed among an Amazonian Dark Earth (ADE, black carbon (BC and its adjacent non-anthropogenic oxisoil. The bacterial 16S rRNA gene (OTU richness estimated by pyrosequencing was higher in ADE than BC. The most abundant bacterial phyla in ADE soils and BC were Proteobacteria—24% ADE, 15% BC; Acidobacteria—10% ADE, 21% BC; Actinobacteria—7% ADE, 12% BC; Verrucomicrobia, 8% ADE; 9% BC; Firmicutes—3% ADE, 8% BC. Overall, unclassified bacteria corresponded to 36% ADE, and 26% BC. Regardless of current land uses, our data suggest that soil microbial community structures may be strongly influenced by the historical soil management and that anthrosols in Amazonia, of anthropogenic origins, in addition to their capacity of enhancing crop yields, may also improve microbial diversity, with the support of the black carbon, which may sustain a particular and unique habitat for the

  7. Evaluation of directional normalization methods for Landsat TM/ETM+ over primary Amazonian lowland forests

    Science.gov (United States)

    Van doninck, Jasper; Tuomisto, Hanna

    2017-06-01

    Biodiversity mapping in extensive tropical forest areas poses a major challenge for the interpretation of Landsat images, because floristically clearly distinct forest types may show little difference in reflectance. In such cases, the effects of the bidirectional reflection distribution function (BRDF) can be sufficiently strong to cause erroneous image interpretation and classification. Since the opening of the Landsat archive in 2008, several BRDF normalization methods for Landsat have been developed. The simplest of these consist of an empirical view angle normalization, whereas more complex approaches apply the semi-empirical Ross-Li BRDF model and the MODIS MCD43-series of products to normalize directional Landsat reflectance to standard view and solar angles. Here we quantify the effect of surface anisotropy on Landsat TM/ETM+ images over old-growth Amazonian forests, and evaluate five angular normalization approaches. Even for the narrow swath of the Landsat sensors, we observed directional effects in all spectral bands. Those normalization methods that are based on removing the surface reflectance gradient as observed in each image were adequate to normalize TM/ETM+ imagery to nadir viewing, but were less suitable for multitemporal analysis when the solar vector varied strongly among images. Approaches based on the MODIS BRDF model parameters successfully reduced directional effects in the visible bands, but removed only half of the systematic errors in the infrared bands. The best results were obtained when the semi-empirical BRDF model was calibrated using pairs of Landsat observation. This method produces a single set of BRDF parameters, which can then be used to operationally normalize Landsat TM/ETM+ imagery over Amazonian forests to nadir viewing and a standard solar configuration.

  8. Development of a biocompatible magnetic nanofluid by incorporating SPIONs in Amazonian oils

    Science.gov (United States)

    Gaspar, André S.; Wagner, Friedrich E.; Amaral, Vítor S.; Costa Lima, Sofia A.; Khomchenko, Vladimir A.; Santos, Judes G.; Costa, Benilde F. O.; Durães, Luísa

    2017-02-01

    Higher quality magnetic nanoparticles are needed for use as magnetic nanoprobe in medical imaging techniques and cancer therapy. Moreover, the phytochemistry benefits of some Amazonian essential oils have sparked great interest for medical treatments. In this work, a magnetic nanoprobe was developed, allying the biocompatibility and superparamagnetism of iron oxide nanoparticles (SPIONs) with benefits associated with Amazonian oils from Copaiba and Andiroba trees. SPIONs were obtained by two thermal decomposition procedures and different amounts of precursors (iron acetylacetonates). Their characterization was accomplished by Fourier transform infrared spectroscopy, thermogravimetric analysis, transmission electron microscopy (TEM), X-ray diffraction (XRD), Mössbauer spectroscopy and magnetization. The obtained nanoparticles composition and magnetic properties were not affected by the relative proportion of iron(II) and iron(III) in the precursor system. However, when changing the reducing and stabilizing agents the coating layer shows different compositions/relative weight - the more promising SPIONs have a coating mainly composed by oleylamine and an iron oxide:coating wt% ratio of 55:45. Nanoparticles size distributions were very narrow and centred in the average size of 6-7 nm. Cellular assays confirmed the biocompatibility of SPIONs and their effective internalization in human colon cancer cells. Mössbauer/XRD results indicated maghemite as their main iron oxide phase, but traces of magnetite proved to be present. Magnetization saturations of 57 emu/g at 5 K and 42 emu/g at 300 K were achieved. With incorporation of SPIONs into Copaiba and Andiroba essential oils, these values show a 4-fold decrease, but the supermagnetic behaviour is preserved providing the effective formation of a nanofluid.

  9. Brazil : Eradicating Child Labor in Brazil

    OpenAIRE

    World Bank

    2001-01-01

    The report reviews evidence of child labor in Brazil, and the Government's efforts to eradicate its worst forms, by examining background assessments of ongoing programs for its prevention. It seeks to identify promising strategies, addressing the needs of highly vulnerable children in urban areas, engaged in activities such as drug commerce, prostitution, or other dangerous activities. One...

  10. Plant parasitic nematodes from Bahia State, Brazil: The genus Xiphinema Cobb, 1913 (Dorylaimoidea)

    NARCIS (Netherlands)

    Loof, P.A.A.; Sharma, R.D.

    1979-01-01

    A review is given of the Xiphinema species occurring in the south-eastern part of Bahia, Brazil. Nine species were found, two of which are new: X. dimidiatum with mammillate tail, females are pseudomonodelphic; and X. paritaliae, differing from X. italiae chiefly by larger size, not expanded lip reg

  11. Frequency of human leukocyte antigen (hla in patients with malaria and in the general population of Humaitá county, Amazonas state, Brazil

    Directory of Open Access Journals (Sweden)

    Domingos Alves Meira

    1987-09-01

    Full Text Available In August 1983,85 inhabitants of the municipality of Humaitá, Amazonas State, Brazil were studied to determine the prevalence of antigens to HLA-A, -B, -C and DR. Thirty-eight were sick with malaria due to Plasmodium falciparum. All subjects were examined for splenomegaly, blood parasitaemia and antibodies to malaria. They constituted three groups: 1 25 subjects native to the Amazon region who had never had malaria; 2 38 Amazonian subjects who had malaria in the past or currently had an infection; 3 22 patients with malaria who had acquired the infection in the Amazon Region but came from other regions of Brazil. Blood was taken from each person, the lymphocytes were separated and typed by the test of microlymphocytotoxicity. There was a high frequency of antigens that could not be identified in the groups studied which suggests the existence of a homozygote or phenotype not identified in the population. There was a high frequency of the phenotype Ag(W24 (44.7% in group 2 when compared with group 1 (32% or group 3 (9%. Also the individuals in group 2 showed an elevated frequency of antigen DR(480% when compared with group 1 (36.6% or group 3 (16.6%. These observations suggest the possibility of a genetic susceptibility to malaria among Amazonian residents and indicate a necessity for more extensive studies of the frequency of HLA antigens among inhabitants of this endemic malarial zone.

  12. Multiple micronutrients in powder delivered through primary health care reduce iron and vitamin A deficiencies in young Amazonian children.

    Science.gov (United States)

    Oliveira, Cristieli Sm; Sampaio, Patrícia; Muniz, Pascoal T; Cardoso, Marly A

    2016-11-01

    We evaluated the effect of home fortification with multiple micronutrient powder (MNP) on anaemia and micronutrient status of young Amazonian children. A pragmatic controlled trial was performed. A control group (CG) of children aged 11-14 months was recruited in the routine of primary health-care centres for assessing anaemia and micronutrient status. At the same time, an intervention group (IG) of infants aged 6-8 months was recruited in the same health centres to receive MNP daily in complementary feeding for 2 months. The IG children were assessed 4-6 months after enrolment (n 112) when they had reached the age of the CG participants (n 128) for comparisons. Primary health centres in Rio Branco city, Brazilian Amazon. A total of 240 children ageddeficiency (VAD; serum retinol complementary feeding delivered through primary health care was effective in reducing iron and vitamin A deficiencies among young Amazonian children.

  13. Workplan for Catalyzing Collaboration with Amazonian Universities in the Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA)

    Science.gov (United States)

    Brown, I. Foster; Moreira, Adriana

    1997-01-01

    Success of the Large-Scale Biosphere-Atmospheric Experiment in Amazonia (LBA) program depends on several critical factors, the most important being the effective participation of Amazonian researchers and institutions. Without host-county counterparts, particularly in Amazonia, many important studies cannot he undertaken due either to lack of qualified persons or to legal constraints. No less important, the acceptance of the LBA program in Amazonia is also dependent on what LBA can do for improving the scientific expertise in Amazonia. Gaining the active investment of Amazonian scientists in a comprehensive research program is not a trivial task. Potential collaborators are few, particularly where much of the research was to be originally focused - the southern arc of Brazilian Amazonia. The mid-term goals of the LBA Committee on Training and Education are to increase the number of collaborators and to demonstrate that LBA will be of benefit to the region.

  14. "Apu Ollantay": Inca Theatre as an example of the modes of interaction between the Incas and Western Amazonian societies

    Directory of Open Access Journals (Sweden)

    Cristiana Bertazoni

    Full Text Available The article looks closely at the Quechua play "Apu Ollantay" in order to better understand the relationships of power that the Incas established with the Amazonian corner of their empire, known in Inca terms as Antisuyu. It is argued that the drama "Apu Ollantay" functioned as a social and political device in order to enhance Inca imperial magnitude and project an image of a magnanimous ruler.

  15. Parasitism of the isopod Artystone trysibia in the fish Chaetostoma dermorhynchum from the Tena River (Amazonian region, Ecuador).

    Science.gov (United States)

    Junoy, Juan

    2016-01-01

    The isopod Artystone trysibia Schioedte, 1866 is described by using a collection of specimens that were found parasitizing loricariid fish Chaetostoma dermorhynchum Boulenger, 1887 in the Tena River (Napo province, Ecuador, Amazonian region). Additionally to freshly collected specimens, complementary data of the parasite was obtained from preserved fishes at Ecuadorian museums. This is the first record of A. trysibia in Ecuador, and the most upstream location for the species. The new host fish, Chaetostoma dermorhynchum, is used locally as food.

  16. Understory Bird Communities in Amazonian Rainforest Fragments: Species Turnover through 25 Years Post-Isolation in Recovering Landscapes

    OpenAIRE

    Stouffer, Philip C.; Johnson, Erik I.; Bierregaard, Richard O.; Thomas E Lovejoy

    2011-01-01

    Inferences about species loss following habitat conversion are typically drawn from short-term surveys, which cannot reconstruct long-term temporal dynamics of extinction and colonization. A long-term view can be critical, however, to determine the stability of communities within fragments. Likewise, landscape dynamics must be considered, as second growth structure and overall forest cover contribute to processes in fragments. Here we examine bird communities in 11 Amazonian rainforest fragme...

  17. Late Pleistocene echimyid rodents (Rodentia, Hystricognathi from northern Brazil

    Directory of Open Access Journals (Sweden)

    THAIS M.F. FERREIRA

    2016-06-01

    Full Text Available ABSTRACT Echimyidae (spiny rats, tree rats and the coypu is the most diverse family of extant South American hystricognath rodents (caviomorphs. Today, they live in tropical forests (Amazonian, coastal and Andean forests, occasionally in more open xeric habitats in the Cerrado and Caatinga of northern South America, and open areas across the southern portion of the continent (Myocastor. The Quaternary fossil record of this family remains poorly studied. Here, we describe the fossil echimyids found in karst deposits from southern Tocantins, northern Brazil. The analyzed specimens are assigned to Thrichomys sp., Makalata cf. didelphoides and Proechimys sp. This is the first time that a fossil of Makalata is reported. The Pleistocene record of echimyids from this area is represented by fragmentary remains, which hinders their determination at specific levels. The data reported here contributes to the understanding of the ancient diversity of rodents of this region, evidenced until now in other groups, such as the artiodactyls, cingulates, carnivores, marsupials, and squamate reptiles.

  18. Spathaspora brasiliensis sp. nov., Spathaspora suhii sp. nov., Spathaspora roraimanensis sp. nov. and Spathaspora xylofermentans sp. nov., four novel (D)-xylose-fermenting yeast species from Brazilian Amazonian forest.

    Science.gov (United States)

    Cadete, Raquel M; Melo, Monaliza A; Zilli, Jerri E; Vital, Marcos J S; Mouro, Adriane; Prompt, Alice H; Gomes, Fátima C O; Stambuk, Boris U; Lachance, Marc-André; Rosa, Carlos A

    2013-02-01

    Four new D-xylose fermenting yeast species of the clade Spathaspora were recovered from rotting-wood samples in a region of Amazonian forest, Northern Brazil. Three species produced unconjugated asci with a single elongated ascospore with curved ends. These species are described as Spathaspora brasiliensis, Spathaspora suhii and Spathaspora roraimanensis. Two isolates of an asexually reproducing species belonging to the Spathaspora clade were also obtained and they are described as Spathaspora xylofermentans. All these species are able to ferment D-xylose during aerobic batch growth in rich YP (1 % yeast extract, 2 % peptone and 2 % D-xylose) medium, albeit with differing efficiencies. The type strains are Spathaspora brasiliensis sp. nov UFMG-HMD19.3 (=CBMAI 1425=CBS 12679), Spathaspora suhii sp. nov. UFMG-XMD16.2 (=CBMAI 1426=CBS 12680), Spathaspora roraimanensis sp. nov. UFMG-XMD23.2 (CBMAI 1427=CBS 12681) and Spathaspora xylofermentans sp. nov. UFMG-HMD23.3 (=CBMAI 1428=CBS 12682).

  19. Audiology in Brazil.

    Science.gov (United States)

    Bevilacqua, Maria Cecilia; Novaes, Beatriz Caiuby; Morata, Thais C

    2008-02-01

    The profession of audiology took root in Brazil nearly a half a century ago and has since blossomed into a flourishing, well-developed field. Currently, audiologists in Brazil work at private institutions, including private medical practices and dedicated speech and hearing clinics. They are also employed in a wide array of public institutions, including community clinics, elementary schools, colleges, and universities. In both the private sector and health clinics, audiologists perform diagnostic evaluations of auditory and vestibular disorders, select and fit hearing aids, and provide aural rehabilitation. At the public level, they assist with workers' health programs, dispense hearing aids, and aural rehabilitation. There is always room to grow, however, and the future of audiology in Brazil holds both challenges and opportunity. The following article will sketch the development of audiology training and practice in Brazil, provide a picture of how the field stands today, and summarize the unique challenges which the profession faces in this large and diverse nation.

  20. Paleotsunamis in Eastern Taiwan

    Science.gov (United States)

    Yen, Jiun-Yee; Yu, Neng-Ti; Hirakawa, Kazuomi; Chyi, Shyh-Jeng; Huang, Shao-Yi

    2017-04-01

    Although Taiwan is located in the active collision zone between Eurasian and the Philippine Sea plate with very high seismicity in and surrounding the island, and supposedly highly susceptible to tsunami hazard. However, there is no record of tsunami hazard in the past one hundred years, and only very few historical records show some possible extreme event occurred. Therefore study of tsunami was scarce in Taiwan. Although historical records do show possible tsunami events, the records were too sparse and incomplete to confidently reconstruct the paleotsunami events. In the past few years, numerical simulations based on possible tsunami-genic zones near Taiwan show that the island could be affected by the correctly directed tsunami. Nevertheless, there is no detail, scientific research of paleotsunami records yet in Taiwan. Our field survey in eastern Taiwan (facing the western Pacific Ocean) along the coast uncovered several outcrops contain gravels embedded in well-developed soil layers. The rounded meta-sandstone gravels are clearly beach-origin and were brought to their current location upon extreme wave events, which is composed of either volcanic-clastic deposits from nearby hills or organic soil layers formed locally. Our investigation indicates that there are at least 3 events in the northern half of eastern Taiwan and at least 2 events in southern part of eastern Taiwan. Although these outcrops are next to the shoreline and Taiwan is susceptible from typhoons, these gravels could be farther away from the beach at the time of their deposition due to current high retreat rate of the sea cliff. Further investigations are needed to delineate possible sources of tsunamis that caused the deposits.

  1. An Amazonian rainforest and its fragments as a laboratory of global change.

    Science.gov (United States)

    Laurance, William F; Camargo, José L C; Fearnside, Philip M; Lovejoy, Thomas E; Williamson, G Bruce; Mesquita, Rita C G; Meyer, Christoph F J; Bobrowiec, Paulo E D; Laurance, Susan G W

    2017-05-30

    We synthesize findings from one of the world's largest and longest-running experimental investigations, the Biological Dynamics of Forest Fragments Project (BDFFP). Spanning an area of ∼1000 km(2) in central Amazonia, the BDFFP was initially designed to evaluate the effects of fragment area on rainforest biodiversity and ecological processes. However, over its 38-year history to date the project has far transcended its original mission, and now focuses more broadly on landscape dynamics, forest regeneration, regional- and global-change phenomena, and their potential interactions and implications for Amazonian forest conservation. The project has yielded a wealth of insights into the ecological and environmental changes in fragmented forests. For instance, many rainforest species are naturally rare and hence are either missing entirely from many fragments or so sparsely represented as to have little chance of long-term survival. Additionally, edge effects are a prominent driver of fragment dynamics, strongly affecting forest microclimate, tree mortality, carbon storage and a diversity of fauna. Even within our controlled study area, the landscape has been highly dynamic: for example, the matrix of vegetation surrounding fragments has changed markedly over time, succeeding from large cattle pastures or forest clearcuts to secondary regrowth forest. This, in turn, has influenced the dynamics of plant and animal communities and their trajectories of change over time. In general, fauna and flora have responded differently to fragmentation: the most locally extinction-prone animal species are those that have both large area requirements and low tolerance of the modified habitats surrounding fragments, whereas the most vulnerable plants are those that respond poorly to edge effects or chronic forest disturbances, and that rely on vulnerable animals for seed dispersal or pollination. Relative to intact forests, most fragments are hyperdynamic, with unstable or

  2. The Amazonian Floodplains, an ecotype with challenging questions on volatile organic compound (VOC) emissions

    Science.gov (United States)

    Kesselmeier, J.

    2012-12-01

    Volatile organic compound (VOC) emissions are affected by a variety of biotic and abiotic factors such as light intensity, temperature, CO2 and drought. Another factor usually overlooked but very important for the tropical rainforest in Amazonia is regular flooding. According to recent estimates, the total Amazonian floodplain area easily ranges up to 700,000 km^2, including whitewater river floodplains (várzea) blackwater regions (igapó) and further clearwater regions. Regarding the total Amazonian wetlands the area sums up to more than 2.000.000 km^2, i.e. 30% of Amazonia. To survive the flooding periods causing anoxic conditions for the root system of up to several months, vegetation has developed several morphological, anatomical and physiological strategies. One is to switch over the root metabolism to fermentation, thus producing ethanol as one of the main products. Ethanol is a toxic metabolite which is transported into the leaves by the transpiration stream. From there it can either be directly emitted into the atmosphere, or can be re-metabolized to acetaldehyde and/or acetate. All of these compounds are volatile enough to be partly released into the atmosphere. We observed emissions of ethanol, acetaldehyde and acetic acid under root anoxia. Furthermore, plant stress induced by flooding also affected leaf primary physiological processes as well as other VOC emissions such as the release of isoprenoids and other volatiles. For example, Hevea spruceana could be identified as a monoterpene emitting tree species behaving differently upon anoxia depending on the origin, with increasing emissions of the species from igapó and decreasing with the corresponding species from várzea. Contrasting such short term inundations, studies of VOC emissions under long term conditions (2-3 months) did not confirm the ethanol/acetaldehyde emissions, whereas emissions of other VOC species decreased considerably. These results demonstrate that the transfer of our knowledge

  3. Wood Polymer Composites Technology Supporting the Recovery and Protection of Tropical Forests: The Amazonian Phoenix Project

    Directory of Open Access Journals (Sweden)

    Antonio D. Nobre

    2009-12-01

    Full Text Available The Amazon Rain Forest has attracted worldwide attention due its large scale services to climate and also due to the green house gas emissions arising from deforestation. Contributing to the later and detrimental to the former, timber logging in the region has very low efficiency (only 16% in the production chain. Such timber extraction, often referred to as selective logging, has been claimed as a sustainable extractive industry, because the forest is said to restore itself through regenerative growth. But forest regeneration in the Amazon occurs naturally only in a very limited scale, resulting that large scale, low efficiency logging poses a big treat to the functional integrity of the biome, supplying to the market only a fraction of what it could if done differently. So, instead of extracting big centennial logs from the forests, the Amazonian Phoenix project proposes that large expanses of degraded lands be reforested using pioneer plants species from the forest itself. These plants have the capacity to heal gaps in the canopy, being able to grow and produce woody biomass in very extreme conditions. The idea is to mimic the regenerative dynamics of the natural ecosystem in short cycle agrosilvicultural production areas, utilizing a variety of technologies to transform raw fibers from these fast growth native plants into a variety of materials with high aggregated value. This communication presents the research on natural fibers by the Polymeric Composites Group within the Amazonian Phoenix Project. Sustainable technologies employing materials with good and responsible ecological footprints are important and necessary stimulus for a change in the destructive economical activities present in the Amazon frontiers. The relatively well established wood polymer composites technology, for example, is a good candidate solution. Two research and development fields are proposed: the first one considers production systems with simple and cheap

  4. Diverse Early Life-History Strategies in Migratory Amazonian Catfish: Implications for Conservation and Management.

    Directory of Open Access Journals (Sweden)

    Jens C Hegg

    Full Text Available Animal migrations provide important ecological functions and can allow for increased biodiversity through habitat and niche diversification. However, aquatic migrations in general, and those of the world's largest fish in particular, are imperiled worldwide and are often poorly understood. Several species of large Amazonian catfish carry out some of the longest freshwater fish migrations in the world, travelling from the Amazon River estuary to the Andes foothills. These species are important apex predators in the main stem rivers of the Amazon Basin and make up the region's largest fishery. They are also the only species to utilize the entire Amazon Basin to complete their life cycle. Studies indicate both that the fisheries may be declining due to overfishing, and that the proposed and completed dams in their upstream range threaten spawning migrations. Despite this, surprisingly little is known about the details of these species' migrations, or their life history. Otolith microchemistry has been an effective method for quantifying and reconstructing fish migrations worldwide across multiple spatial scales and may provide a powerful tool to understand the movements of Amazonian migratory catfish. Our objective was to describe the migratory behaviors of the three most populous and commercially important migratory catfish species, Dourada (Brachyplatystoma rousseauxii, Piramutaba (Brachyplatystoma vaillantii, and Piraíba (Brachyplatystoma filamentosum. We collected fish from the mouth of the Amazon River and the Central Amazon and used strontium isotope signatures ((87Sr/(86Sr recorded in their otoliths to determine the location of early rearing and subsequent. Fish location was determined through discriminant function classification, using water chemistry data from the literature as a training set. Where water chemistry data was unavailable, we successfully in predicted (87Sr/(86Sr isotope values using a regression-based approach that related

  5. Provenance of late Oligocene to quaternary sediments of the Ecuadorian Amazonian foreland basin as inferred from major and trace element geochemistry and Nd-Sr isotopic composition

    Science.gov (United States)

    Roddaz, Martin; Christophoul, Frédéric; Burgos Zambrano, José David; Soula, Jean-Claude; Baby, Patrice

    2012-08-01

    Oligocene to Quaternary deposits from the Oriente Amazonian foreland basin (Ecuador and Peru) were analyzed for major and trace element geochemistry (46 and 32 samples respectively) and Nd-Sr isotopic systematics (n = 10). Chemical Index of Alteration values lower than those of other Amazonian foreland basin sediments and scattering along the AK join in the A-CN-K diagram indicate that the Oriente foreland basin has been continuously fed by poorly to moderately weathered sediments having an overall Andesitic composition since the Oligocene. Chemical ratios such as Cr/Th and Th/Sc as well as Eu anomaly and Nd-Sr isotopic compositions indicate that most of the analyzed sediments contained a greater proportion of volcanic arc rock material than the other Amazonian foreland basin sediments. When compared with the older sediments The Quaternary sediments are characterized by a greater contribution of the volcanic arc source. The composition of the sediments deposited in the Ecuadorian Amazonian foreland basin is mainly controlled by geodynamic processes. We suspect the Late Pliocene-Pleistocene subduction of the Carnegie ridge to be responsible for the back arc volcanism feeding the Amazonian foreland with more basic materials. Input of young Ecuadorian volcanic rocks may explain the difference in Sr and Nd isotopic ratios of suspended sediments between the Solimoes and the Madeira rivers.

  6. Using biometry to elucidate eddy flux observations of net ecosystem carbon exchange: evidence for episodic disturbance as the cause of net carbon loss from an old-growth Amazonian rainforest

    Science.gov (United States)

    Saleska, S. R.; Wofsy, S. C.; Rice, A. H.; Hutyra, L.; Pyle, E. H.; Camargo, P. B.; Portilho, K.; Marques, D. F.

    2002-12-01

    Net ecosystem exchange (NEE) of CO2, measured by eddy-covariance in a central Amazonian old-growth forest, showed ecosystem C loss of 0.5 to 2 MgC/ha/yr (see Wofsy et al invited presentation). This is in contrast to other published eddy flux studies of Amazonian C-balance most of which have reported significant uptake. In order to independently test eddy flux results, and elucidate the underlying forest vegetation dynamics driving this net loss, we surveyed trees and coarse woody debris in 20 ha of the eddy flux tower footprint (in the Tapaj¢s National Forest, km 67, near Santarém, Par , Brazil, 54d 58'W, 2d 51'S). Net flux to live wood biomass, estimated by resurvey after two years, was 1.49 +/- 0.58 Mg C/ha/yr, the net result of high growth rate (3.28 +/- 0.23 Mg C/ha/yr from a mean bole increment of 0.18 cm), recruitment of new trees (0.61 +/- 0.02 Mg C/ha/yr), and high mortality (-2.4 +/- 0.51 Mg C/ha/yr due to stem mortality of 1.8 percent/yr). The measured net gain in live wood biomass was exceeded, however, by estimated net loss (flux to CWD = -1.7 to -5.0 Mg C/ha/yr) from the large stock of CWD, resulting in an overall estimated flux to aboveground live and dead wood of -0.2 to -3.9 Mg C/ha/yr, a loss consistent with eddy flux. Three observations suggest that an episode of high mortality (possibly caused by El Ni¤o Southern Oscillation events of the 1990s) preceded study initiation and resulted in the current observations of carbon loss: (i) the stock of CWD is large, (ii) all of the net gain in live biomass is due to small-tree growth and recruitment, and (iii) the distribution of stem density was piecewise log-linear with a notable steeper slope for trees less than 40 cm DBH. This scenario confirms predictions that large variations in carbon balance may be expected in even old growth forest, and suggests that climatically-induced disturbance events may mask the relatively small effects on carbon uptake predicted from rising atmospheric carbon dioxide.

  7. Zika: Why Brazil, Why Now

    Science.gov (United States)

    ... medlineplus.gov/news/fullstory_160251.html Zika: Why Brazil, Why Now Several factors -- including economics, climate and ... 5, 2016 THURSDAY, Aug. 4, 2016 (HealthDay News) -- Brazil, by a wide margin, has been the country ...

  8. Analyzing the Effect of Intraseasonal Meteorological Variability and Land Cover on Aerosol-Cloud Interactions During the Amazonian Biomass Burning Season

    Science.gov (United States)

    TenHoeve, J. E.; Remer, L. A.; Jacobson, M. Z.

    2010-01-01

    High resolution aerosol, cloud, water vapor, and atmospheric profile data from the Moderate Resolution Imaging Spectroradiometer (MODIS) are utilized to examine the impact of aerosols on clouds during the Amazonian biomass burning season in Rondnia, Brazil. It is found that increasing background column water vapor (CWV) throughout this transition season between the Amazon dry and wet seasons exerts a strong effect on cloud properties. As a result, aerosol-cloud correlations should be stratified by column water vapor to achieve a more accurate assessment of the effect of aerosols on clouds. Previous studies ignored the systematic changes to meteorological factors during the transition season, leading to possible misinterpretation of their results. Cloud fraction is shown generally to increase with aerosol optical depth (AOD) for both low and high values of column water vapor, whereas the relationship between cloud optical depth (COD) and AOD exhibits a different relationship. COD increases with AOD until AOD approx. 0.25 due to the first indirect (microphysical) effect. At higher values of AOD, COD is found to decrease with increasing AOD, which may be due to: (1) the inhibition of cloud development by absorbing aerosols (radiative effect) and/or (2) a retrieval artifact in which the measured reflectance in the visible is less than expected from a cloud top either from the darkening of clouds through the addition of carbonaceous biomass burning aerosols or subpixel dark surface contamination in the measured cloud reflectance. If (1) is a contributing mechanism, as we suspect, then a linear relationship between the indirect effect and increasing AOD, assumed in a majority of GCMs, is inaccurate since these models do not include treatment of aerosol absorption in and around clouds. The effect of aerosols on both column water vapor and clouds over varying land surface types is also analyzed. The study finds that the difference in column water vapor between forest and

  9. Corporate Governance Country Assessment : Brazil

    OpenAIRE

    World Bank

    2005-01-01

    This report assesses Brazil's corporate governance policy framework. It highlights recent improvements in corporate governance regulation, makes policy recommendations, and provides investors with a benchmark against which to measure corporate governance in Brazil. It is an update of the 2005 corporate governance Report on the Observance of Standards and Codes (ROSC). Brazil's experience o...

  10. [A better Brazil].

    Science.gov (United States)

    Lesser, Jeffrey

    2014-01-01

    Many countries in the Americas describe themselves as "nations of immigrants." In the United States, the myth of the "promised land" suggests that foreigners better themselves upon arrival because the nation is intrinsically great. In Brazil, however, the relationship between immigration and national identity is different. Many intellectuals, politicians, and cultural and economic leaders saw (and see) immigrants as improving an imperfect nation that has been tainted by the history of Portuguese colonialism and African slavery. As a result, immigrants were often hailed as saviors because they modified and improved Brazil, not because they were improved by Brazil. This "improvement" took place through absorption, mixture and with the use of increasingly flexible racial and ethnic categories.

  11. Regeneration of five commercially-valuable tree species after experimental logging in an Amazonian forest

    Directory of Open Access Journals (Sweden)

    Lima Albertina Pimentel

    2002-01-01

    Full Text Available This study investigated the regeneration variation of five commercially valuable tree species in relation to different intensities of felling in fourteen 4-ha plots in an area under experimental forest management. This experiment was carried out in a typical Amazonian tropical forest sample on "terra-firme," in Manaus (AM. Plots were logged 7 and 8 years (1987 and 1988, or 3 years (1993 before the study. All trees with height greater than 2 m, and diameter at breast height (DBH smaller than 10 cm were measured. Only Aniba hostmanniana, Ocotea aciphylla, Licaria pachycarpa, Eschweilera coriacea and Goupia glabra were sufficiently common for individual analyses. These species have high timber values in the local market. Eight years after logging, the species responded differently to logging intensities. The numbers of individuals of Goupia glabra and Aniba hostmanniana were positively related to the intensity of logging, while Ocotea aciphylla, Licaria pachycarpa, and Eschweilera coriacea showed no statistically significant response. In the most recently (1993 logged areas, Goupia glabra and Aniba hostmanniana had higher numbers of individuals than the control plots.

  12. Avian Communities in the Amazonian Cangas Vegetation: Biogeographic Affinities, Components of Beta-Diversity and Conservation.

    Science.gov (United States)

    Borges, Sérgio H; Santos, Marcos P D; Soares, Leonardo M S; Silva, Antonita S DA

    2017-08-14

    The Amazonian cangas is a vegetation type distributed as patches of open vegetation embedded in a matrix of tropical forest and that grows over iron-rich soils in the Serra dos Carajás region. To characterize cangas avifauna, we surveyed birds in eight patches varying from 43 to 1,366 hectares. Cangas avifauna has compositional affinities with savannas widespread throughout the Amazon and other biomes, and we estimate that more than 200 bird species occurs in this habitat. Species composition was relatively homogeneous, and the similarity among cangas patches was the dominant component of the beta-diversity. Bird communities in cangas patches exhibited statistically significant nested structure in respect to species richness and patch size. In contrast, the nested site arrangement was not affected by the isolation of patches. Number of species and composition are moderately affected by the area of cangas patches but not by its degree of isolation. To conserve this unique habitat are necessary a strict protection of carefully chosen patches of cangas and an investigation of the conservation value of secondary vegetation recovered by the mining companies.

  13. Beings of a Feather: Learning About the Lives of Birds with Amazonian Peoples

    Directory of Open Access Journals (Sweden)

    Kevin Jernigan

    2016-12-01

    Full Text Available This article is a memoir of the author's fieldwork experiences studying traditional knowledge of bird species in the Peruvian Amazon. It describes his growth as a researcher, in light of the practical and methodological challenges of carrying out this kind of work. It also relates how the author's thinking has evolved on questions of current theoretical interest in ethnobiology. The first section outlines how the author came to be interested in this topic while pursuing an ethnobotanical dissertation project. Next, the discussion follows his work with the indigenous Aguaruna and Iquito peoples, learning about and documenting their understandings of the nesting, foraging and reproductive behavior of local avian species. On one hand, he found that local people provided details of these behaviors that match, in many ways, the counts of academic ornithologists. However, local interpretations of why these behaviors take place are often framed by some very different assumptions. The author uses Victor Toledo's tripartite framework of kosmos (overarching belief systems, corpus (cognitive categories, and praxis (set of practices to discuss similarities and differences in Aguaruna, Iquito, and academic ornithology. He also discusses his progression of views on the topic of perspectivism and eventual preference for a theoretical framework favoring a polyontological approach to understanding Amazonian ethnoecology.

  14. Social isolation and aggressiveness in the Amazonian juvenile fish Astronotus ocellat