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Sample records for balbina amazonia central

  1. Inter-annual variation (1991-1993) of the substratum-leaf colonization dynamics for aquatic fauna in different habitats of the lake of the hydroelectric of Balbina, Amazon Central, Brazil; Variacao interanual (1991-1993) da dinamica de colonizacao de substrato-folha por fauna aquatica, em diferentes habitats do lago da Hidreletrica de Balbina, Amazonia Central, Amazonas- Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Vela-Pena, Gladys

    1996-07-01

    Experiments on fauna colonization of submersed vegetal substrate in different depths of water column were done to evaluate the benthic community structure in three habitats of the Balbina hydroelectric dam in 1991, 1992 and 1993. In these experiments substrate exposition periods of up to 60 and 75 days were done. The fauna associated to the standard substrate (Mabea caudata) belonged to seven phyla: Arthropoda, Coelenterata, Nematoda, Bryozoa, Annelida, Mollusca an Chordata. The most abundant and frequent families, during the studied period, were Naididae (Tubificida), Chydoridae (Cladocera) and Cenestheridae (Conchostraca), suggesting the persistence of these groups. In general, the pattern of colonization indicates some tendency to increase gradually with time of exposition of the substrate in the environment. Probably, the discontinuity of the tendencies is associated with the insects mobility and emergence. The initial colonization always was higher and quicker in the margin habitat, which indicates that the source of organisms is this habitat. This is due to better conditions of the environment such as availability of food and protection, associated with the submerged vegetation and wood. The community mean density during this study was 7, 312 ind/m{sup 2}. The density, the species richness index, and the diversity were correlated with abiotic variables such as pH, temperature, dissolved oxygen, habitat and depth. Also, the density was correlated with total carbon and ammonium. Species richness was correlated with total carbon, ammonium and water color. The density, diversity and species richness were proportionally inverse to depth of the habitats and total absence of organisms ago 10 meter of depth, different from what is found in bottom of natural environments. This fact was attributed to the high concentration of nutrients, such as ammonium and dissolved iron, to the existence of toxic gases such a sulphide, and to the conditions of hypoxia in the deep

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

    Science.gov (United States)

    Fearnside, Philip M.

    1989-07-01

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

  3. Feeding habits of giant otters Pteronura brasiliensis (Carnivora: Mustelidae in the Balbina hydroelectric reservoir, Central Brazilian Amazon

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    Márcia M. M. Cabral

    2010-02-01

    Full Text Available This study aimed to identify the diet of giant otters, Pteronura brasiliensis (Zimmermann, 1780 in the Balbina reservoir (01º55'S, 59º29'W, to compare it with literature data on the diet of giant otters from non-dammed areas, and to verify the effects of the seasonal changes in water levels on the feeding habits of Balbina otters. A total of 254 feces samples were collected and identified according to the lowest possible taxonomic level. Teleostei fish were present in 100% of the samples; two samples also presented monkey fur (n = 1 and sloth fur (n = 1, suggesting that the diet of P. brasiliensis, in the reservoir, is almost exclusively based on fish. Ten fish families were identified in our samples, six of which were exclusive to the Balbina Lake (not present in the diet of giant otters from non-dammed areas. These six fish families, however, were present in less than 3% of the samples. The fish families with highest representation in the diet of giant otters from non-dammed areas also appeared with higher frequencies in the Balbina Lake, suggesting that the otters have not changed their diet substantially after the implementation of the reservoir. During the high-water period, when the fish are dispersed into the flooded forest and are not very easy to catch, the otters seem to have an opportunistic feeding habit. By contrast, during the low-water period, when prey items are widely available and easier to catch in the reservoir, their feeding habits are more selective.

  4. Balbina's region sustainable development project

    International Nuclear Information System (INIS)

    Hargreaves, Paul

    1994-01-01

    This work presents a planning and administration of an environmental project proposal for Balbina's lake hydroelectric power station restoration. The socio-economic objectives are the hydro-forest bio production development which include fishery, specialized tourism, leisure, besides the processing of industrial raw materials

  5. Age of depositional and weathering events in Central Amazonia

    Science.gov (United States)

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

    2017-08-01

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

  6. Evapotranspiration of deforested areas in central and southwestern Amazonia

    NARCIS (Netherlands)

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

    2012-01-01

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

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

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    Hamada Neusa

    2003-01-01

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

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

    OpenAIRE

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

    2016-01-01

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

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

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    Leandro Talione Sabagh

    2012-02-01

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

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

    NARCIS (Netherlands)

    Martins, M.; Oliveira, M.E.

    1993-01-01

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

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

    Science.gov (United States)

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

    2010-02-01

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

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

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    Ricardo Antonio Marenco

    2015-04-01

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

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

    International Nuclear Information System (INIS)

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

    2012-01-01

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

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

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    RB. Querino

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

  15. Measuring local depletion of terrestrial game vertebrates by central-place hunters in rural Amazonia.

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    Mark I Abrahams

    Full Text Available The degree to which terrestrial vertebrate populations are depleted in tropical forests occupied by human communities has been the subject of an intense polarising debate that has important conservation implications. Conservation ecologists and practitioners are divided over the extent to which community-based subsistence offtake is compatible with ecologically functional populations of tropical forest game species. To quantify depletion envelopes of forest vertebrates around human communities, we deployed a total of 383 camera trap stations and 78 quantitative interviews to survey the peri-community areas controlled by 60 semi-subsistence communities over a combined area of over 3.2 million hectares in the Médio Juruá and Uatumã regions of Central-Western Brazilian Amazonia. Our results largely conform with prior evidence that hunting large-bodied vertebrates reduces wildlife populations near settlements, such that they are only found at a distance to settlements where they are hunted less frequently. Camera trap data suggest that a select few harvest-sensitive species, including lowland tapir, are either repelled or depleted by human communities. Nocturnal and cathemeral species were detected relatively more frequently in disturbed areas close to communities, but individual species did not necessarily shift their activity patterns. Group biomass of all species was depressed in the wider neighbourhood of urban areas rather than communities. Interview data suggest that species traits, especially group size and body mass, mediate these relationships. Large-bodied, large-group-living species are detected farther from communities as reported by experienced informants. Long-established communities in our study regions have not "emptied" the surrounding forest. Low human population density and low hunting offtake due to abundant sources of alternative aquatic protein, suggest that these communities represent a best-case scenario for sustainable

  16. Measuring local depletion of terrestrial game vertebrates by central-place hunters in rural Amazonia

    Science.gov (United States)

    Peres, Carlos A.; Costa, Hugo C. M.

    2017-01-01

    The degree to which terrestrial vertebrate populations are depleted in tropical forests occupied by human communities has been the subject of an intense polarising debate that has important conservation implications. Conservation ecologists and practitioners are divided over the extent to which community-based subsistence offtake is compatible with ecologically functional populations of tropical forest game species. To quantify depletion envelopes of forest vertebrates around human communities, we deployed a total of 383 camera trap stations and 78 quantitative interviews to survey the peri-community areas controlled by 60 semi-subsistence communities over a combined area of over 3.2 million hectares in the Médio Juruá and Uatumã regions of Central-Western Brazilian Amazonia. Our results largely conform with prior evidence that hunting large-bodied vertebrates reduces wildlife populations near settlements, such that they are only found at a distance to settlements where they are hunted less frequently. Camera trap data suggest that a select few harvest-sensitive species, including lowland tapir, are either repelled or depleted by human communities. Nocturnal and cathemeral species were detected relatively more frequently in disturbed areas close to communities, but individual species did not necessarily shift their activity patterns. Group biomass of all species was depressed in the wider neighbourhood of urban areas rather than communities. Interview data suggest that species traits, especially group size and body mass, mediate these relationships. Large-bodied, large-group-living species are detected farther from communities as reported by experienced informants. Long-established communities in our study regions have not “emptied” the surrounding forest. Low human population density and low hunting offtake due to abundant sources of alternative aquatic protein, suggest that these communities represent a best-case scenario for sustainable hunting of

  17. High genetic diversity among and within bitter manioc varieties cultivated in different soil types in Central Amazonia

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    Alessandro Alves-Pereira

    2017-04-01

    Full Text Available Abstract Although manioc is well adapted to nutrient-poor Oxisols of Amazonia, ethnobotanical observations show that bitter manioc is also frequently cultivated in the highly fertile soils of the floodplains and Amazonian dark earths (ADE along the middle Madeira River. Because different sets of varieties are grown in each soil type, and there are agronomic similarities between ADE and floodplain varieties, it was hypothesized that varieties grown in ADE and floodplain were more closely related to each other than either is to varieties grown in Oxisols. We tested this hypothesis evaluating the intra-varietal genetic diversity and the genetic relationships among manioc varieties commonly cultivated in Oxisols, ADE and floodplain soils. Genetic results did not agree with ethnobotanical expectation, since the relationships between varieties were variable and most individuals of varieties with the same vernacular name, but grown in ADE and floodplain, were distinct. Although the same vernacular name could not always be associated with genetic similarities, there is still a great amount of variation among the varieties. Many ecological and genetic processes may explain the high genetic diversity and differentiation found for bitter manioc varieties, but all contribute to the maintenance and amplification of genetic diversity within the manioc in Central Amazonia.

  18. Seasonality of isoprenoid emissions from a primary rainforest in central Amazonia

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    E. G. Alves

    2016-03-01

    Full Text Available Tropical rainforests are an important source of isoprenoid and other volatile organic compound (VOC emissions to the atmosphere. The seasonal variation of these compounds is however still poorly understood. In this study, vertical profiles of mixing ratios of isoprene, total monoterpenes and total sesquiterpenes, were measured within and above the canopy, in a primary rainforest in central Amazonia, using a proton transfer reaction – mass spectrometer (PTR-MS. Fluxes of these compounds from the canopy into the atmosphere were estimated from PTR-MS measurements by using an inverse Lagrangian transport model. Measurements were carried out continuously from September 2010 to January 2011, encompassing the dry and wet seasons. Mixing ratios were higher during the dry (isoprene – 2.68 ± 0.9 ppbv, total monoterpenes – 0.67 ± 0.3 ppbv; total sesquiterpenes – 0.09 ± 0.07 ppbv than the wet season (isoprene – 1.66 ± 0.9 ppbv, total monoterpenes – 0.47 ± 0.2 ppbv; total sesquiterpenes – 0.03 ± 0.02 ppbv for all compounds. Ambient air temperature and photosynthetically active radiation (PAR behaved similarly. Daytime isoprene and total monoterpene mixing ratios were highest within the canopy, rather than near the ground or above the canopy. By comparison, daytime total sesquiterpene mixing ratios were highest near the ground. Daytime fluxes varied significantly between seasons for all compounds. The maximums for isoprene (2.53 ± 0.5 µmol m−2 h−1 and total monoterpenes (1.77 ± 0.05 µmol m−2 h−1 were observed in the late dry season, whereas the maximum for total sesquiterpenes was found during the dry-to-wet transition season (0.77 ± 0.1 µmol m−2 h−1. These flux estimates suggest that the canopy is the main source of isoprenoids emitted into the atmosphere for all seasons. However, uncertainties in turbulence parameterization near the ground could affect estimates of fluxes that come from the ground. Leaf

  19. Seasonality of isoprenoid emissions from a primary rainforest in central Amazonia

    Science.gov (United States)

    Alves, Eliane G.; Jardine, Kolby; Tota, Julio; Jardine, Angela; Yãnez-Serrano, Ana Maria; Karl, Thomas; Tavares, Julia; Nelson, Bruce; Gu, Dasa; Stavrakou, Trissevgeni; Martin, Scot; Artaxo, Paulo; Manzi, Antonio; Guenther, Alex

    2016-03-01

    Tropical rainforests are an important source of isoprenoid and other volatile organic compound (VOC) emissions to the atmosphere. The seasonal variation of these compounds is however still poorly understood. In this study, vertical profiles of mixing ratios of isoprene, total monoterpenes and total sesquiterpenes, were measured within and above the canopy, in a primary rainforest in central Amazonia, using a proton transfer reaction - mass spectrometer (PTR-MS). Fluxes of these compounds from the canopy into the atmosphere were estimated from PTR-MS measurements by using an inverse Lagrangian transport model. Measurements were carried out continuously from September 2010 to January 2011, encompassing the dry and wet seasons. Mixing ratios were higher during the dry (isoprene - 2.68 ± 0.9 ppbv, total monoterpenes - 0.67 ± 0.3 ppbv; total sesquiterpenes - 0.09 ± 0.07 ppbv) than the wet season (isoprene - 1.66 ± 0.9 ppbv, total monoterpenes - 0.47 ± 0.2 ppbv; total sesquiterpenes - 0.03 ± 0.02 ppbv) for all compounds. Ambient air temperature and photosynthetically active radiation (PAR) behaved similarly. Daytime isoprene and total monoterpene mixing ratios were highest within the canopy, rather than near the ground or above the canopy. By comparison, daytime total sesquiterpene mixing ratios were highest near the ground. Daytime fluxes varied significantly between seasons for all compounds. The maximums for isoprene (2.53 ± 0.5 µmol m-2 h-1) and total monoterpenes (1.77 ± 0.05 µmol m-2 h-1) were observed in the late dry season, whereas the maximum for total sesquiterpenes was found during the dry-to-wet transition season (0.77 ± 0.1 µmol m-2 h-1). These flux estimates suggest that the canopy is the main source of isoprenoids emitted into the atmosphere for all seasons. However, uncertainties in turbulence parameterization near the ground could affect estimates of fluxes that come from the ground. Leaf phenology seemed to be an important driver of seasonal

  20. Convergent Adaptations: Bitter Manioc Cultivation Systems in Fertile Anthropogenic Dark Earths and Floodplain Soils in Central Amazonia

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    Fraser, James Angus; Alves-Pereira, Alessandro; Junqueira, André Braga; Peroni, Nivaldo; Clement, Charles Roland

    2012-01-01

    Shifting cultivation in the humid tropics is incredibly diverse, yet research tends to focus on one type: long-fallow shifting cultivation. While it is a typical adaptation to the highly-weathered nutrient-poor soils of the Amazonian terra firme, fertile environments in the region offer opportunities for agricultural intensification. We hypothesized that Amazonian people have developed divergent bitter manioc cultivation systems as adaptations to the properties of different soils. We compared bitter manioc cultivation in two nutrient-rich and two nutrient-poor soils, along the middle Madeira River in Central Amazonia. We interviewed 249 farmers in 6 localities, sampled their manioc fields, and carried out genetic analysis of bitter manioc landraces. While cultivation in the two richer soils at different localities was characterized by fast-maturing, low-starch manioc landraces, with shorter cropping periods and shorter fallows, the predominant manioc landraces in these soils were generally not genetically similar. Rather, predominant landraces in each of these two fertile soils have emerged from separate selective trajectories which produced landraces that converged for fast-maturing low-starch traits adapted to intensified swidden systems in fertile soils. This contrasts with the more extensive cultivation systems found in the two poorer soils at different localities, characterized by the prevalence of slow-maturing high-starch landraces, longer cropping periods and longer fallows, typical of previous studies. Farmers plant different assemblages of bitter manioc landraces in different soils and the most popular landraces were shown to exhibit significantly different yields when planted in different soils. Farmers have selected different sets of landraces with different perceived agronomic characteristics, along with different fallow lengths, as adaptations to the specific properties of each agroecological micro-environment. These findings open up new avenues for

  1. Convergent adaptations: bitter manioc cultivation systems in fertile anthropogenic dark earths and floodplain soils in Central Amazonia.

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    James Angus Fraser

    Full Text Available Shifting cultivation in the humid tropics is incredibly diverse, yet research tends to focus on one type: long-fallow shifting cultivation. While it is a typical adaptation to the highly-weathered nutrient-poor soils of the Amazonian terra firme, fertile environments in the region offer opportunities for agricultural intensification. We hypothesized that Amazonian people have developed divergent bitter manioc cultivation systems as adaptations to the properties of different soils. We compared bitter manioc cultivation in two nutrient-rich and two nutrient-poor soils, along the middle Madeira River in Central Amazonia. We interviewed 249 farmers in 6 localities, sampled their manioc fields, and carried out genetic analysis of bitter manioc landraces. While cultivation in the two richer soils at different localities was characterized by fast-maturing, low-starch manioc landraces, with shorter cropping periods and shorter fallows, the predominant manioc landraces in these soils were generally not genetically similar. Rather, predominant landraces in each of these two fertile soils have emerged from separate selective trajectories which produced landraces that converged for fast-maturing low-starch traits adapted to intensified swidden systems in fertile soils. This contrasts with the more extensive cultivation systems found in the two poorer soils at different localities, characterized by the prevalence of slow-maturing high-starch landraces, longer cropping periods and longer fallows, typical of previous studies. Farmers plant different assemblages of bitter manioc landraces in different soils and the most popular landraces were shown to exhibit significantly different yields when planted in different soils. Farmers have selected different sets of landraces with different perceived agronomic characteristics, along with different fallow lengths, as adaptations to the specific properties of each agroecological micro-environment. These findings open

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

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    Benchimol, Maíra; Peres, Carlos A

    2015-01-01

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

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

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    Maíra Benchimol

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

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

    Directory of Open Access Journals (Sweden)

    James A. Fraser

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

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

    Directory of Open Access Journals (Sweden)

    James A. Fraser

    2008-08-01

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

  6. DISTRIBUTION OF ORGANIC CARBON IN DIFFERENT SOIL FRACTIONS IN ECOSYSTEMS OF CENTRAL AMAZONIA

    Directory of Open Access Journals (Sweden)

    Jean Dalmo de Oliveira Marques

    2015-02-01

    Full Text Available Organic matter plays an important role in many soil properties, and for that reason it is necessary to identify management systems which maintain or increase its concentrations. The aim of the present study was to determine the quality and quantity of organic C in different compartments of the soil fraction in different Amazonian ecosystems. The soil organic matter (FSOM was fractionated and soil C stocks were estimated in primary forest (PF, pasture (P, secondary succession (SS and an agroforestry system (AFS. Samples were collected at the depths 0-5, 5-10, 10-20, 20-40, 40-60, 60-80, 80-100, 100-160, and 160-200 cm. Densimetric and particle size analysis methods were used for FSOM, obtaining the following fractions: FLF (free light fraction, IALF (intra-aggregate light fraction, F-sand (sand fraction, F-clay (clay fraction and F-silt (silt fraction. The 0-5 cm layer contains 60 % of soil C, which is associated with the FLF. The F-clay was responsible for 70 % of C retained in the 0-200 cm depth. There was a 12.7 g kg-1 C gain in the FLF from PF to SS, and a 4.4 g kg-1 C gain from PF to AFS, showing that SS and AFS areas recover soil organic C, constituting feasible C-recovery alternatives for degraded and intensively farmed soils in Amazonia. The greatest total stocks of carbon in soil fractions were, in decreasing order: (101.3 Mg ha-1 of C - AFS > (98.4 Mg ha-1 of C - FP > (92.9 Mg ha-1 of C - SS > (64.0 Mg ha-1 of C - P. The forms of land use in the Amazon influence C distribution in soil fractions, resulting in short- or long-term changes.

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

    Science.gov (United States)

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

    2003-01-01

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

  8. Sequential Management of Commercial Rosewood (Aniba rosaeodora Ducke Plantations in Central Amazonia: Seeking Sustainable Models for Essential Oil Production

    Directory of Open Access Journals (Sweden)

    Pedro Medrado Krainovic

    2017-11-01

    Full Text Available Rosewood (Aniba rosaeodora Ducke is an endangered tree that produces essential oil of high commercial value. However, technical-scientific knowledge about cultivation is scarce and studies are needed to examine the management viability. The current study evaluated rosewood aboveground biomass management, measuring the export of nutrients resulting from harvesting and testing sustainable management models. The crown of 36 rosewood trees were pruned and 108 trees cut at 50 cm above the soil in two regions in Central Amazonia. Post-harvest performance of sprouting shoots was evaluated and after, sprouting shoots were pruned so that the development of two, three and all shoots was permitted. Nutrient stock estimation was calculated as the product of mass and nutrient concentration, which allowed nutritional replacement to be estimated. The pruning facilitates regrowth by 40.11% of the initial mass while by cut regrow 1.45%. Chemical attributes of regrowth biomass differed significantly prior to management and regrowth had a significant correlation with the reserves in root tissues and with the pre -management status of the individual tree. Driving sprouts resulted in significantly larger growth increments and may provide a form of management that can viably be adopted. Biomass sequential management resulted in high nutrient exports and the amount of fertilizer needed for replenishment depended on the intensity and frequency of cropping. Compared with the cut of the tree, pruning the canopy reduces fertilizers that are required to replenish amount by 44%, decreasing to 26.37% in the second rotation. The generated knowledge contributes to this silvicultural practice as it becomes ecologically and economically viable.

  9. Papel trófico del microbial loop en un lago de inundación en la Amazonia Central

    Directory of Open Access Journals (Sweden)

    Pedro Caraballo Gracia

    2012-01-01

    Full Text Available Con el propósito de evaluar la participación de las bacterias heterotróficas en el flujo de carbono en la cadena trófica de un lago de inundación amazónico, colectas mensuales de estos microorganismos fueron realizadas durante el año hidrológico de diciembre de 2007 hasta noviembre de 2008, en las regiones litoral, pelágica y de macrófitas acuáticas del lago Catalão, en la Amazonia Central brasilera. Las bacterias fueron multiplicadas in vitro, usando como sustrato el carbono orgánico disuelto (COD del lago en cada una de las regiones estudiadas, para posterior análisis de la abundancia de isotopos estables de carbono y nitrógeno. Estos datos fueron confrontados con los valores de COD de los cuatro periodos limnológicos del lago (seca, inundación, llena y bajada de aguas. En general se encontró que la fuente principal de carbono de las bacterias heterotróficas fue aquella de origen C4, que presentó un aporte mínimo de 75%, en la medida en que el δ13C de las bacterias presentó valor medio de -17,72‰ ± 2,25. Confrontando ese valor, con el δ13C del zooplancton en el mismo período (-33,04‰±3,81 se concluye que el aporte de las bacterias heterotróficas al flujo de carbono hacia niveles tróficos superiores en el lago estudiado es mínimo.

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

    Science.gov (United States)

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

    2005-01-01

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

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

    Science.gov (United States)

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

    1999-07-01

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

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

    Directory of Open Access Journals (Sweden)

    S. S. de Sá

    2017-06-01

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

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

    Directory of Open Access Journals (Sweden)

    B. Wick

    2005-01-01

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

  14. Sedimentology and Palynostratigraphy of a Pliocene-Pleistocene (Piacenzian to Gelasian) deposit in the lower Negro River: Implications for the establishment of large rivers in Central Amazonia

    Science.gov (United States)

    Soares, Emílio Alberto Amaral; D'Apolito, Carlos; Jaramillo, Carlos; Harrington, Guy; Caputo, Mario Vicente; Barbosa, Rogério Oliveira; Bonora dos Santos, Eneas; Dino, Rodolfo; Gonçalves, Alexandra Dias

    2017-11-01

    The Amazonas fluvial system originates in the Andes and runs ca. 6700 km to the Atlantic Ocean, having as the main affluent the Negro River (second largest in water volume). The Amazonas transcontinental system has been dated to the late Miocene, but the timing of origin and evolutionary processes of its tributaries are still poorly understood. Negro River alluvial deposits have been dated to the middle to late Pleistocene. Recently, we studied a number of boreholes drilled for the building of a bridge at the lower course of the Negro River. A thin (centimetric) sedimentary deposit was found, laterally continuous for about 1800 m, unconformably overlaying middle Miocene strata and unconformably overlain by younger Quaternary deposits. This deposit consists predominantly of brownish-gray sandstones cemented by siderite and with subordinate mudstone and conglomerate beds. Palynological, granulometric, textural and mineralogical data suggest that the initial Negro River aggradation took place in the deep incised valley under anoxic conditions and subsequently along the floodplain, with efficient transport of mixed origin particles (Andean and Amazonic). Angiosperm leaves, wood and pollen are indicative of a tropical continental palaeoenvironment. A well preserved palynoflora that includes Alnipollenites verus, Grimsdalea magnaclavata and Paleosantalaceaepites cingulatus suggests a late Pliocene to early Pleistocene (Piacenzian to Gelasian) age for this unit, which was an age yet unrecorded in the Amazon Basin. These results indicate that by the late Pliocene-early Pleistocene, large scale river activity was occurring in Central Amazonia linking this region with the Andean headwaters, and therefore incompatible with Central Amazonia barriers like the Purus arch.

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

    Directory of Open Access Journals (Sweden)

    Haugaasen Torbjørn

    2006-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Ubaldo de Almeida Farias Junior

    2015-10-01

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

  17. Determinants of plant community assembly in a mosaic of landscape units in central Amazonia: ecological and phylogenetic perspectives.

    Directory of Open Access Journals (Sweden)

    María Natalia Umaña

    Full Text Available The Amazon harbours one of the richest ecosystems on Earth. Such diversity is likely to be promoted by plant specialization, associated with the occurrence of a mosaic of landscape units. Here, we integrate ecological and phylogenetic data at different spatial scales to assess the importance of habitat specialization in driving compositional and phylogenetic variation across the Amazonian forest. To do so, we evaluated patterns of floristic dissimilarity and phylogenetic turnover, habitat association and phylogenetic structure in three different landscape units occurring in terra firme (Hilly and Terrace and flooded forests (Igapó. We established two 1-ha tree plots in each of these landscape units at the Caparú Biological Station, SW Colombia, and measured edaphic, topographic and light variables. At large spatial scales, terra firme forests exhibited higher levels of species diversity and phylodiversity than flooded forests. These two types of forests showed conspicuous differences in species and phylogenetic composition, suggesting that environmental sorting due to flood is important, and can go beyond the species level. At a local level, landscape units showed floristic divergence, driven both by geographical distance and by edaphic specialization. In terms of phylogenetic structure, Igapó forests showed phylogenetic clustering, whereas Hilly and Terrace forests showed phylogenetic evenness. Within plots, however, local communities did not show any particular trend. Overall, our findings suggest that flooded forests, characterized by stressful environments, impose limits to species occurrence, whereas terra firme forests, more environmentally heterogeneous, are likely to provide a wider range of ecological conditions and therefore to bear higher diversity. Thus, Amazonia should be considered as a mosaic of landscape units, where the strength of habitat association depends upon their environmental properties.

  18. Determinants of Plant Community Assembly in a Mosaic of Landscape Units in Central Amazonia: Ecological and Phylogenetic Perspectives

    Science.gov (United States)

    Umaña, María Natalia; Norden, Natalia; Cano, Ángela; Stevenson, Pablo R.

    2012-01-01

    The Amazon harbours one of the richest ecosystems on Earth. Such diversity is likely to be promoted by plant specialization, associated with the occurrence of a mosaic of landscape units. Here, we integrate ecological and phylogenetic data at different spatial scales to assess the importance of habitat specialization in driving compositional and phylogenetic variation across the Amazonian forest. To do so, we evaluated patterns of floristic dissimilarity and phylogenetic turnover, habitat association and phylogenetic structure in three different landscape units occurring in terra firme (Hilly and Terrace) and flooded forests (Igapó). We established two 1-ha tree plots in each of these landscape units at the Caparú Biological Station, SW Colombia, and measured edaphic, topographic and light variables. At large spatial scales, terra firme forests exhibited higher levels of species diversity and phylodiversity than flooded forests. These two types of forests showed conspicuous differences in species and phylogenetic composition, suggesting that environmental sorting due to flood is important, and can go beyond the species level. At a local level, landscape units showed floristic divergence, driven both by geographical distance and by edaphic specialization. In terms of phylogenetic structure, Igapó forests showed phylogenetic clustering, whereas Hilly and Terrace forests showed phylogenetic evenness. Within plots, however, local communities did not show any particular trend. Overall, our findings suggest that flooded forests, characterized by stressful environments, impose limits to species occurrence, whereas terra firme forests, more environmentally heterogeneous, are likely to provide a wider range of ecological conditions and therefore to bear higher diversity. Thus, Amazonia should be considered as a mosaic of landscape units, where the strength of habitat association depends upon their environmental properties. PMID:23028844

  19. Late Holocene paleoenvironments of the floodplain of the Solimões River, Central Amazonia, based on the palynological record of Lake Cabaliana

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    Natália de Paula Sá

    Full Text Available ABSTRACT The core PD-67 of 160 cm depth was collected from the delta of Lake Cabaliana situated on the Solimões River. Seventeen samples were removed for palynological and sedimentological analysis and three for radiocarbon analysis. Two dry periods, both in the Late Holocene, were observed (2800-2550 cal yr BP, 1450-550 cal yr BP separated by a wetter phase (2550-1450 cal yr BP. In 2800-2550 cal yr BP, varzea forests of Alchornea, Symmeria, Cecropia, Alternanthera and Asteraceae were predominant. Beginning in 2,550-1450 cal yr BP, the varzea was characterized by pioneer elements, such as Cassia, Laetia, Mabea, Symmeria and Cecropia, and by the expansion of Poaceae, Cyperaceae, Sagittaria, Montrichardia and Asteraceae. In 1450-550 cal yr BP the succession of varzea continued with Pseudobombax, Laetia, Luehea/Lueheopsis and Ryanaea increasing simultaneously with the terra firme vegetation of Rutaceae, Sapotaceae, Styrax, Scleronema, Anthurium, Araceae, pteridophytes and Pariana. The successional dynamics at Lake Cabaliana indicated that the local varzea had become established recently, and is composed of a mosaic of different successional stages of vegetation influenced mainly by flood pulse and variation in rainfall. It is therefore possible to propose that the recent climate history of Central Amazonia reflects changes in rainfall patterns in the basin.

  20. Nodulation of legumes, nitrogenase activity of roots and occurrence of nitrogen-fixing Azospirillum spp. In representative soils of central Amazonia

    Energy Technology Data Exchange (ETDEWEB)

    Sylvester-Bradley, R; De Oliverira, L A; De Podesta Filho, J A; John, T V

    1980-12-01

    Leguminosae do not predominate in the Brazilian Amazon rain forest, although they are among the five best represented families. Plant roots from various soils were examined for the presence of nodules, acetylene-reducing activity and N/sub 2/-fixing Azospirillum spp. Abundant nodulation was found in black earth (''terra preta dos indios'') and in one case on sandy soil under campinarana vegetation along a tributary of the upper Rio Negro. In sandy latosol some nodules occurred in secondary forest and fewer in primary forest. Legumes in disturbed clayey or sandy latosol showed more frequent nodulation. Primary forest on alluvial (''varzea'') soil, and in Bahia coastal rain forest on sandy latosol and Erythrina glauca used for shading cacao plantations were abundantly nodulated. Acetylene reduction assays showed no, or very little, nitrogenase activity of roots from primary or secondary forest on clayey latosol near Manaus. Nodulated roots from secondary forest on sandy latosol showed acetylene-reducing activity. High rates of acetylene reduction were observed in nodulated roots of primary forest on alluvial ''varzea'' soil. Root samples showed ethylene absorption in controls without acetylene which might interfere with the results of acetylene reduction tests. The incidence of Azospirillum was also higher in black earth than the other soils examined, and in soils with higher pH. The hypothesis that Azospirillum is associated with Trema micantha roots was refuted. Roots and soils collected under cultivated grasses showed a higher incidence of Azospirillum when fertilized with phosphorus and lime. Results indicate that nitrogen fixation did occur in association with roots in some soils, but not with roots of primary or secondary forest on clayey latosol in the vicinity of Manaus, which is the most common soil in Central Amazonia. The possible reasons for this are discussed.

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

    Science.gov (United States)

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

    2006-11-01

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

  2. Leptoglossus lonchoides Allen (Heteroptera, Coreidae), causente de la caida de los frutos de Bactris gasipaes (Palmae) en la Amazonia central

    OpenAIRE

    Couturier, Guy; Clement, C.R.; Viana Filho, P.

    1991-01-01

    #Leptoglossus lonchoïdes$ Allen (Heteroptera Coreidae) provoque la chute des fruits de #Bactris gasipaes$ HBK (Palmae) en Amazonie centrale. Les plantations de "pejibaye", #B.gasipaes$, un palmier neotropical domestiqué, souffrent d'importantes chutes de jeunes fruits en Amazonie centrale (Manaus, Amazonas, Brésil), dues en partie, peut-être principalement, à la punaise #L. lonchoïdes$. Dans cet article, on évalue l'importance économique des dégâts et on décrit l'insecte. (Résumé d'auteur)...

  3. Shaded Relief with Height as Color, Lake Balbina, near Manaus, Brazil

    Science.gov (United States)

    2002-01-01

    These two images show exactly the same area, Lake Balbina near Manaus, Brazil. The image on the left was created using the best global topographic data set previously available, the U.S. Geological Survey's GTOPO30. In contrast, the much more detailed image on the right was generated with data from the Shuttle Radar Topography Mission, which collected enough measurements to map 80 percent of Earth's landmass at this level of precision.Lake Balbina is a man-made reservoir created to supply hydroelectric power to the city of Manaus, located 125 kilometers (77 miles) to the south. The reservoir is located on the Uatuma River and drains a 19,100-square-kilometer (7,340-square-mile) basin of mostly upland topography where the relief extends from 30 meters (98 feet) to 200 meters(650 feet) in elevation. The lake includes a cluster of approximately 1,500 islands separated by submerged, shallow valleys within a flooded water-surface area of 2,400 square kilometers (920 square miles). Prior to the dam closure on October 1, 1987, the annually averaged flow on thriver was about 450 cubic meters (16,000 cubic feet) per second. Water depths in the full reservoir average 7.4 meters (24 feet). Because the vegetation was not cleared before filling, the lake consists mostly of forest and inundated trunks of dead, leafless trees.For some parts of the globe, Shuttle Radar Topography Mission measurements are 30 times more precise than previously available topographical information, according to NASA scientists. Mission data will be a welcome resource for national and local governments, scientists, commercial enterprises, and members of the public alike. The applications are as diverse as earthquake and volcano studies, flood control, transportation, urban and regional planning, aviation, recreation, and communications. The data's military applications include mission planning and rehearsal, modeling, and simulation.This image combines two types of Shuttle Radar Topography Mission data

  4. CCN activity and organic hygroscopicity of aerosols downwind of an urban region in central Amazonia: seasonal and diel variations and impact of anthropogenic emissions

    Science.gov (United States)

    Thalman, Ryan; de Sá, Suzane S.; Palm, Brett B.; Barbosa, Henrique M. J.; Pöhlker, Mira L.; Lizabeth Alexander, M.; Brito, Joel; Carbone, Samara; Castillo, Paulo; Day, Douglas A.; Kuang, Chongai; Manzi, Antonio; Ng, Nga Lee; Sedlacek, Arthur J., III; Souza, Rodrigo; Springston, Stephen; Watson, Thomas; Pöhlker, Christopher; Pöschl, Ulrich; Andreae, Meinrat O.; Artaxo, Paulo; Jimenez, Jose L.; Martin, Scot T.; Wang, Jian

    2017-10-01

    During the Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) campaign, size-resolved cloud condensation nuclei (CCN) spectra were characterized at a research site (T3) 60 km downwind of the city of Manaus, Brazil, in central Amazonia for 1 year (12 March 2014 to 3 March 2015). Particle hygroscopicity (κCCN) and mixing state were derived from the size-resolved CCN spectra, and the hygroscopicity of the organic component of the aerosol (κorg) was then calculated from κCCN and concurrent chemical composition measurements. The annual average κCCN increased from 0.13 at 75 nm to 0.17 at 171 nm, and the increase was largely due to an increase in sulfate volume fraction. During both wet and dry seasons, κCCN, κorg, and particle composition under background conditions exhibited essentially no diel variations. The constant κorg of ˜ 0. 15 is consistent with the largely uniform and high O : C value (˜ 0. 8), indicating that the aerosols under background conditions are dominated by the aged regional aerosol particles consisting of highly oxygenated organic compounds. For air masses strongly influenced by urban pollution and/or local biomass burning, lower values of κorg and organic O : C atomic ratio were observed during night, due to accumulation of freshly emitted particles, dominated by primary organic aerosol (POA) with low hygroscopicity, within a shallow nocturnal boundary layer. The O : C, κorg, and κCCN increased from the early morning hours and peaked around noon, driven by the formation and aging of secondary organic aerosol (SOA) and dilution of POA emissions into a deeper boundary layer, while the development of the boundary layer, which leads to mixing with aged particles from the residual layer aloft, likely also contributed to the increases. The hygroscopicities associated with individual organic factors, derived from PMF (positive matrix factorization) analysis of AMS (aerosol mass spectrometry) spectra, were estimated through

  5. CCN activity and organic hygroscopicity of aerosols downwind of an urban region in central Amazonia: seasonal and diel variations and impact of anthropogenic emissions

    Directory of Open Access Journals (Sweden)

    R. Thalman

    2017-10-01

    Full Text Available During the Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5 campaign, size-resolved cloud condensation nuclei (CCN spectra were characterized at a research site (T3 60 km downwind of the city of Manaus, Brazil, in central Amazonia for 1 year (12 March 2014 to 3 March 2015. Particle hygroscopicity (κCCN and mixing state were derived from the size-resolved CCN spectra, and the hygroscopicity of the organic component of the aerosol (κorg was then calculated from κCCN and concurrent chemical composition measurements. The annual average κCCN increased from 0.13 at 75 nm to 0.17 at 171 nm, and the increase was largely due to an increase in sulfate volume fraction. During both wet and dry seasons, κCCN, κorg, and particle composition under background conditions exhibited essentially no diel variations. The constant κorg of ∼ 0. 15 is consistent with the largely uniform and high O : C value (∼ 0. 8, indicating that the aerosols under background conditions are dominated by the aged regional aerosol particles consisting of highly oxygenated organic compounds. For air masses strongly influenced by urban pollution and/or local biomass burning, lower values of κorg and organic O : C atomic ratio were observed during night, due to accumulation of freshly emitted particles, dominated by primary organic aerosol (POA with low hygroscopicity, within a shallow nocturnal boundary layer. The O : C, κorg, and κCCN increased from the early morning hours and peaked around noon, driven by the formation and aging of secondary organic aerosol (SOA and dilution of POA emissions into a deeper boundary layer, while the development of the boundary layer, which leads to mixing with aged particles from the residual layer aloft, likely also contributed to the increases. The hygroscopicities associated with individual organic factors, derived from PMF (positive matrix factorization analysis of AMS (aerosol mass

  6. Meteorological context of the onset and end of the rainy season in Central Amazonia during the GoAmazon2014/5

    Directory of Open Access Journals (Sweden)

    J. A. Marengo

    2017-06-01

    Full Text Available The onset and demise of the rainy season in Amazonia are assessed in this study using meteorological data from the GoAmazon experiment, with a focus on the 2014–2015 rainy season. In addition, global reanalyses are also used to identify changes in circulation leading to the establishment of the rainy season in the region. Our results show that the onset occurred in January 2015, 2–3 pentads later than normal, and the rainy season during the austral summer of 2015 contained several periods with consecutive dry days in both Manacapuru and Manaus, which are not common for the wet season, and resulted in below-normal precipitation. The onset of the rainy season has been strongly associated with changes in large-scale weather conditions in the region due to the effect of the Madden–Julian Oscillation (MJO. Regional thermodynamic indices and the height of the boundary layer did not present a significant difference between the onset and demise of the wet season of 2015. This suggests that local changes, such as those in the regional thermodynamic characteristics, may not have influenced its onset. Thus, variability of the large-scale circulation was responsible for regional convection and rainfall changes in Amazonia during the austral summer of 2014–2015.

  7. DO “DESCONTRUIR” PARA CONSTRUIR: TRANSFORMAÇÕES SOCIOAMBIENTAIS NO ENTORNO DA UHE DE BALBINA – PRESIDENTE FIGUEIREDO (AM – BRASIL./ “Desconstruct to construct”: socio-environmental transformation in surrounding Balbina Hydroeletric – Presidente Figueired

    Directory of Open Access Journals (Sweden)

    Rodrigo de Oliveira Félix

    2017-12-01

    Full Text Available A busca por desenvolvimento econômico e energético levou o governo federal brasileiro, em pleno período de ditadura militar, a avançar para o norte do país, onde se constatou um relevante potencial hidroelétrico presente na região. A UHE de Balbina-AM representa uma das várias intervenções políticas organizadas e implementadas como promessas de progresso para a Amazônia. Tal construção foi concebida sob diversas problemáticas, muitas das quais questionáveis até os dias de hoje, isso porque ocorreram modificações sociais, ambientais e econômicas no entorno do reservatório construído. Nesta pesquisa realizou-se um estudo onde foi possível demonstrar e analisar as transformações ocorridas no entorno do Reservatório da Usina Hidrelétrica de Balbina, tendo por finalidade entender como se organiza o atual espaço geográfico. Para a pesquisa foi utilizado o método geossistêmico usando como metodologia: as coletas de campo, imagens de satélite para elaboração de mapas, pesquisa bibliográfica e documental, além de visitas aos institutos que colaboraram com informações complementares. Através da pesquisa foi possível identificar as modificações na paisagem e o processo de desterritorialização dos Waimiri- atroaris ocasionados pela implementação do projeto da UHE de Balbina, além é claro no que diz respeito às novas formas de uso e ocupação do solo. Os resultados também demonstram que mesmo com os grandes impactos ocorridos pela construção e implantação da usina, a água do reservatório contribuiu para a formação de novas territorialidades ocasionando as transformações socioespaciais em seu entorno.

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

    Science.gov (United States)

    Jaquetti, Roberto K; Gonçalves, José Francisco C

    2017-01-01

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

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

    Directory of Open Access Journals (Sweden)

    ROBERTO K. JAQUETTI

    2017-08-01

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

  10. Downstream impacts of a Central Amazonian hydroelectric dam on tree growth and mortality in floodplain forests

    Science.gov (United States)

    Resende, A. F. D.; Silva, T. S. F.; Silva, J. D. S.; Piedade, M. T. F.; Streher, A. S.; Ferreira-Ferreira, J.; Schongart, J.

    2017-12-01

    The flood pulse of large Amazonian Rivers is characterized by predictable high- and low-water periods during the annual cycle, and is the main driving force in the floodplains regulating decomposition, nutrient cycles, productivity, life cycles and growth rhythms of floodplains' biota. Over at least 20 millions of years, tree species in these ecosystems developed complex adaptative mechanisms to tolerate flooding, such as the tree species Macrolobium acaciifolium (Fabaceae) and Eschweilera tenuifolia (Lecythidaceae) occupying the lower topographic positions in the floodplain forests along the oligothrophic black-water rivers. Tree growth occurs mainly during terrestrial phase, while during the aquatic phase the anoxic conditions result into a cambial dormancy and formation of annual tree rings. The hydroelectric dam Balbina which was installed in the Uatumã River (central Amazonia) during the 1980s altered significantly the flood pulse regime resulting into higher minimum and lower maximum annual water levels. The suppression of the terrestrial phase caused large-scale mortality of flood-adapted trees growing on the lower topographic positions, as evidenced by radiocarbon dating and cross-dating techniques (dendrochronology). In this study we estimated the extension of dead forests using high resolution ALOS/PALSAR radar images, for their detection along a fluvial distance of more than 280 km downstream of the power plant. Further we analyzed tree growth of 60 living individuals of E. tenuifolia by tree-ring analyses comparing the post- and pre-dam periods. We evaluated the impacts of the altered hydrological regime on tree growth considering ontogenetic effects and the fluvial distance of the trees to the dam. Since the Balbina power plant started operating the associated igapó forests lost about 11% of its cover. We found a significant reduction of tree growth of E. tenuifolia during the post-dam period as a consequence of the increasing aquatic phase duration

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

    Directory of Open Access Journals (Sweden)

    Arlem Nascimento de Oliveira

    2004-01-01

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

  12. Greenhouse gases study in Amazonia

    International Nuclear Information System (INIS)

    D'Amelio, Monica Tais Siqueira

    2006-01-01

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

  13. Reservoir stratification affects methylmercury levels in river water, plankton, and fish downstream from Balbina hydroelectric dam, Amazonas, Brazil.

    Science.gov (United States)

    Kasper, Daniele; Forsberg, Bruce R; Amaral, João H F; Leitão, Rafael P; Py-Daniel, Sarah S; Bastos, Wanderley R; Malm, Olaf

    2014-01-21

    The river downstream from a dam can be more contaminated by mercury than the reservoir itself. However, it is not clear how far the contamination occurs downstream. We investigated the seasonal variation of methylmercury levels in the Balbina reservoir and how they correlated with the levels encountered downstream from the dam. Water, plankton, and fishes were collected upstream and at sites between 0.5 and 250 km downstream from the dam during four expeditions in 2011 and 2012. Variations in thermal stratification of the reservoir influenced the methylmercury levels in the reservoir and in the river downstream. Uniform depth distributions of methylmercury and oxygen encountered in the poorly stratified reservoir during the rainy season collections coincided with uniformly low methylmercury levels along the river downstream from the dam. During dry season collections, the reservoir was strongly stratified, and anoxic hypolimnion water with high methylmercury levels was exported downstream. Methylmercury levels declined gradually to 200 km downstream. In general, the methylmercury levels in plankton and fishes downstream from the dam were higher than those upstream. Higher methylmercury levels observed 200-250 km downstream from the dam during flooding season campaigns may reflect the greater inflow from tributaries and flooding of natural wetlands that occurred at this time.

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

    Directory of Open Access Journals (Sweden)

    Carlos Elias Braga

    2011-12-01

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

  15. Pre-Columbian Earthworks in Coastal Amazonia

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    Stéphen Rostain

    2010-03-01

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

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

    Directory of Open Access Journals (Sweden)

    Roberto K. Jaquetti

    2016-04-01

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

  17. Eficiência no uso dos nutrientes por espécies pioneiras crescidas em pastagens degradadas na Amazônia central Nutrient use efficiency for pioneer species grown on abandoned pastures in central Amazonia

    Directory of Open Access Journals (Sweden)

    Carlos E. M. Silva

    2006-12-01

    colonizing species. The experiment conducted on a six year-old secondary forest, consisted of four treatments: control; phosphorus addition (P; phosphorus and lime addition (P+Cal; and phosphorus, lime and gypsum addition (P+Cal+G. Leaf gas exchange, soil and leaf nutrient concentration were determined eight months after the treatment application. There was a significant response by species to the addition of phosphorus and lime (P+Cal and P+Cal+G. The species, Bellucia grossularioides accumulated more N, P and Zn in the leaves, while Laetia procera accumulated more Ca and Mn. The species Vismia japurensis had higher nutrient use efficiency, as a function of the higher photosynthetic rates. Vismia japurensis presented lower P concentrations than Bellucia grossularioides, suggesting that is well adapted to environments low in nutrients, as this species often occurs in degraded areas in Amazonia.

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

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    Liana O. Anderson

    2012-05-01

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

  19. The environment and the hydroelectric in Amazonia

    International Nuclear Information System (INIS)

    La Rovere, E.L.

    1992-01-01

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

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

    DEFF Research Database (Denmark)

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

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

  1. Neutrons, radiation and archaeology: a multi analytical case study of incised rim tradition ceramics in Central Amazon; Neutrons, radiacao e arqueologia: estudo de caso multianalitico de ceramicas da tradicao borda incisa na Amazonia Central

    Energy Technology Data Exchange (ETDEWEB)

    Hazenfratz-Marks, Roberto

    2014-07-01

    This thesis is an interdisciplinary archaeometric study involving archaeological ceramic material from two large archaeological sites in Central Amazon, namely Lago Grande and Osvaldo, on the confluence region of Negro and Solimoes rivers. It was tested a hypothesis about the existence of an exchange network between the former inhabitants of those sites, focusing on material and/or technological exchange. That hypothesis has implications for archaeological theories of human occupation of the pre-colonial Central Amazon, which try to relativise the role of ecological difficulties of the tropical forest as a limiting factor for the emergence of social complexity in the region. The physical-chemical characterization of potsherds and clay samples near the sites was carried out by: instrumental neutron activation analysis (INAA) to determine the elemental chemical composition; electron paramagnetic resonance (EPR) to determine the firing temperature; X-ray diffraction (XRD) to determine the mineralogical composition; and dating by optically stimulated luminescence (OSL). Previous studies showed that Osvaldo and Lago Grande were occupied by people which produced pottery classified in the Manacapuru and Paredao phases, subclasses of the Incised Rim Tradition, around the 5-10th and 7-12th centuries BC, respectively. INAA results were analyzed by multivariate statistical methods, whereby two chemical groups of pottery were defined for each archaeological site. Significant variation in firing temperatures and mineralogical composition were not identified for such groups. By integration of the results with archaeological data, the superposition between pairs of chemical groups was interpreted as a correlate of an ancient exchange network, although it was not possible to define if it existed exclusively between Lago Grande and Osvaldo. On the contrary, it was suggested that Lago Grande participated in a more extensive exchange network by comparison of two chemical groups

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

    Directory of Open Access Journals (Sweden)

    Arlem Nascimento de Oliveira

    2005-09-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    D' Amelio, Monica Tais Siqueira

    2006-07-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    D' Amelio, Monica Tais Siqueira

    2006-07-01

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

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

    Directory of Open Access Journals (Sweden)

    N. O. Aguiar

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

  6. The domestication of Amazonia before European conquest.

    Science.gov (United States)

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

    2015-08-07

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

  7. Miocene freshwater Mollusca from western Brazilian Amazonia

    NARCIS (Netherlands)

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

    2006-01-01

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

  8. Lizards of Brazilian Amazonia (Reptilia: Squamata)

    NARCIS (Netherlands)

    Avila-Pires, T.C.S.

    1995-01-01

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

  9. Geographic pattern of genetic diversity in natural populations of Rosewood (Aniba rosaeodora, in the Central Amazonia Padrão geográfico de diversidade genética em populações naturais de Pau-rosa (Aniba rosaeodora, na Amazônia Central

    Directory of Open Access Journals (Sweden)

    Ronaldo Pereira Santos

    2008-01-01

    Full Text Available Rosewood (Aniba rosaeodora Ducke, Lauraceae is an Amazonian evergreen tree and a source of the purest linalool, the main component of its essential oil, which is very valuable in the international perfumery market. After decades of over-exploitation it is currently considered as threatened. We evaluated the genetic diversity and its distribution in four populations in Central Amazonia. Thirty-five reliable RAPD markers were generated, of which 32 were polymorphic (91.4%. Variation was higher within the populations (76.5%; p O Pau-rosa (Aniba rosaeodora Ducke, Lauraceae é uma árvore amazônica fonte do mais puro linalol, o qual é o principal componente do seu óleo essencial e muito valioso no mercado internacional de perfumaria. Após várias décadas de intensa exploração, a espécie foi levada à categoria de ameaçada de extinção. Quatro populações naturais distribuídas na bacia Amazônia Central foram avaliadas quanto ao nível e a distribuição da diversidade genética. Trinta e cinco marcadores RAPD reprodutíveis foram gerados, dos quais 32 foram polimórficos (91,4%. A diversidade foi maior dentro das populações (76,5%; p < 0,0001 e a distribuição geográfica contribuiu para a diferenciação entre as populações (23,4%; p < 0,0001. A AMOVA indicou que pode haver uma influência parcial do Rio Amazonas no fluxo gênico (3,3%; p < 0,0001, mas foram identificadas evidências de fluxo gênico atravessando o rio. Houve diferenças significativas nas freqüências dos marcadores (p < 0,05 e o fluxo gênico estimado foi relativamente baixo (Nm = 2,02. A correlação entre a distância genética e o fluxo gênico foi de - 0,95 (p = 0,06 e para a distância geográfica e o fluxo gênico foi de - 0,78 (p = 0,12. Houve um padrão geográfico de variabilidade ao longo do eixo Leste - Oeste, influenciado também pelo Rio Amazonas, o que sugere que o rio poderia funcionar como uma barreira para o fluxo gênico. Apesar de amea

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

    Directory of Open Access Journals (Sweden)

    Quézia Ribeiro Fonseca

    2008-06-01

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

  11. Abundance of two Dendrocincla woodcreepers (aves: Dendrocolaptidae in relation to forest structure in Central Amazonia O uso do habitat por duas espécies de arapaçus Dendrocincla (aves: Dendrocolaptidae em relação a estrutura da floresta na Amazônia Central

    Directory of Open Access Journals (Sweden)

    Renato Cintra

    2006-01-01

    Full Text Available Few studies have been conducted to verify how the structure of the forest affects the occurence and abundance of neotropical birds. Our research was undertaken between January 2002 and July 2004 at the Reserva Ducke, near Manaus (02º55',03º01'S; 59º53',59º59'W in central Amazonia, to verify how the forest structure affects the occurrence and abundance of two bird species: the Plain-brown Woodcreeper Dendrocincla fuliginosa and the White-chinned Woodcreeper Dendrocincla merula. Bird species occurrence was recorded using lines of 20 mist-nets (one sample unit, along 51 1-km transects distributed along 9 pararel 8 km trails covering an area of 6400 ha. Along these transects, we placed 50 x 50m plots where we recorded forest structure components (tree abundance, canopy openness, leaf litter, standing dead trees, logs, proximity to streams, and altitude. We then related these variables to bird occurence and abundance using multiple logistic and multiple linear regression models, respectively. We found that D. fuliginosa frequently used plateau areas; being more abundant in areas with more trees. On the other hand, D. merula occurred more frequently and was more abundant in areas with low tree abundance. Our results suggest that although both species overlap in the reserve (both were recorded in at least 68% of the sampled sites, they differ in the way they use the forest microhabitats. Therefore, local variation in the forest structure may contribute to the coexistence of congeneric species and may help to maintain local alpha diversity.Em florestas neotropicais, poucos estudos tem sido conduzidos para verificar como a estrutura da floresta afeta o uso desse ambiente por aves. Este estudo foi realizado entre Janeiro de 2002 e Julho de 2004 na Reserva Ducke próximo a Manaus (02º55',03º01'S; 59º53',59º59'W, para verificar como a estrutura da floresta afeta a ocorrência e abundância de duas espécies de aves: o Arapaçu-pardo, Dendrocincla

  12. Small farmers and deforestation in Amazonia

    Science.gov (United States)

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

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

  13. Neogene climate evolution in Amazonia and the Brazilian Northeast

    NARCIS (Netherlands)

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

    2014-01-01

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

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

    Science.gov (United States)

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

    2015-03-01

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

  15. Within-canopy sesquiterpene ozonolysis in Amazonia

    Science.gov (United States)

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

    2011-10-01

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

  16. On the Relationship of Rainfall and Temperature across Amazonia

    Science.gov (United States)

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

    2017-12-01

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

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

    Science.gov (United States)

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

    2004-01-01

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

  18. Biogeochemistry and ecology of terrestrial ecosystems of Amazonia

    Science.gov (United States)

    Malhi, Yadvinder; Davidson, Eric A.

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

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

    Science.gov (United States)

    Ribeiro-Júnior, Marco A; Amaral, Silvana

    2017-05-22

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

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

    Science.gov (United States)

    Armenteras, Dolors; Retana, Javier

    2012-01-01

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

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

    Directory of Open Access Journals (Sweden)

    James L Crainey

    2016-01-01

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

  2. Astrocaryum (palmae in Amazonia a preliminary treatment

    Directory of Open Access Journals (Sweden)

    1992-01-01

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

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

    Science.gov (United States)

    Ribeiro-Júnior, Marco A; Amaral, Silvana

    2016-12-09

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

  4. Paleoclimates of Amazonia: An ice-age view

    NARCIS (Netherlands)

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

    2014-01-01

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

  5. Molluscan radiations and landscape evolution in Miocene Amazonia

    NARCIS (Netherlands)

    Wesselingh, F.P.

    2008-01-01

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

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

    Science.gov (United States)

    Lima, Carlos H. R.; AghaKouchak, Amir

    2017-12-01

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

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

    NARCIS (Netherlands)

    Hoorn, C.; Vonhof, H.B.

    2006-01-01

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

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

    Directory of Open Access Journals (Sweden)

    SALINAS NELSON

    2007-12-01

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

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

    Directory of Open Access Journals (Sweden)

    1992-01-01

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

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

    Science.gov (United States)

    Ribeiro-Júnior, Marco A

    2015-07-08

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

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

    Science.gov (United States)

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

    2017-12-01

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

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

    NARCIS (Netherlands)

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

    2000-01-01

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

  13. Soil water storage in an upland forest after selective logging in Central Amazonia Armazenamento de água no solo após extração seletiva de madeira em floresta de terra firme na Amazônia Central

    Directory of Open Access Journals (Sweden)

    S. J. F. Ferreira

    2004-02-01

    Full Text Available Soil water storage of Central Amazonian soil profiles in upland forest plots subjected to selective logging (in average, 8 trees or 34, 3 m³ of timber per hectare were removed was measured in four layers, down to a depth of 70 cm. The study lasted 27-months and was divided in two phases: measurements were carried out nearly every week during the first 15 months; in the following year, five intensive periods of measurements were performed. Five damage levels were compared: (a control (undisturbed forest plot; (b centre of the clearing/gap; (c edge of the gap; (d edge of the remaining forest; and (e remaining forest. The lowest values for water storage were found in the control (296 ± 19.1 mm, while the highest were observed (333 ± 25.8 mm in the centre of the gap, during the dry period. In the older gaps (7.5-8.5 year old, soil water storage was similar to the remaining and the control forest, indicating a recovery of hydric soil properties to nearly the levels prior to selective logging.Foi medido o armazenamento de água em perfis de solo de 0-70 cm, divididos em quatro camadas em parcelas de floresta de terra firme na Amazônia Central, submetidas à extração seletiva de madeira, tendo sido retiradas, em média, 8 árvores por hectare ou 34 m³ de madeira. O estudo foi realizado num período de 27 meses em duas fases: na primeira, as medidas foram, na sua maioria, semanais, num período de 15 meses. Na segunda, as medidas foram feitas em cinco períodos intensivos. Foram comparados cinco tratamentos: (a controle (floresta intacta, (b centro da clareira, (c borda da clareira, (d borda da floresta remanescente e (e floresta remanescente. Os valores mais baixos de armazenamento de água no solo (296 ± 19,1 mm foram encontrados no controle, enquanto os mais altos foram medidos no centro da clareira (333 ± 25,8 mm, no período seco. Nas clareiras mais antigas (7,5-8,5 anos de idade, os armazenamentos de água no solo foram similares aos da

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

    OpenAIRE

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

    2015-01-01

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

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

    International Nuclear Information System (INIS)

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

    1991-01-01

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

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

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    Rodolfo Burgos de Luna

    2017-10-01

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

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

    Science.gov (United States)

    Morton, Douglas

    2010-01-01

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

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

    Science.gov (United States)

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

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

  19. Karyological analysis of Proechimys cuvieri and Proechimys guyannensis (Rodentia, Echimyidae from central Amazon

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Faresin e Silva

    2012-01-01

    Full Text Available The aim was to characterize the karyotype of rodents of the genus Proechimys from three localities in the central Brazilian Amazon, in the search for new markers that might shed light on our understanding of the taxonomy and evolutionary history of this taxon. Two karyotypes were found, viz., 2n = 28, FN = 46 in individuals from the NRSP (Cuieiras River and REMAN (Manaus, and 2n = 46, FN = 50 in individuals from the Balbina Hydroelectric Plant. While individuals with the karyotype with 2n = 28 chromosomes were morphologically associated with Proechimys cuvieri, their karyotype shared similarities with those of the same diploid number in two other regions. Although three karyotypes are described for Proechimys cuvieri, no geographic distribution pattern that defined a cline could be identified. Based on the morphological examination of voucher specimens and additional results from molecular analysis, the karyotype with 2n = 46 and FN = 50 could be associated with P. guyannensis.

  20. Karyological analysis of Proechimys cuvieri and Proechimys guyannensis (Rodentia, Echimyidae) from central Amazon.

    Science.gov (United States)

    E Silva, Carlos Eduardo Faresin; Eler, Eduardo Schmidt; da Silva, Maria Nazareth F; Feldberg, Eliana

    2012-01-01

    The aim was to characterize the karyotype of rodents of the genus Proechimys from three localities in the central Brazilian Amazon, in the search for new markers that might shed light on our understanding of the taxonomy and evolutionary history of this taxon. Two karyotypes were found, viz., 2n = 28, FN = 46 in individuals from the NRSP (Cuieiras River) and REMAN (Manaus), and 2n = 46, FN = 50 in individuals from the Balbina Hydroelectric Plant. While individuals with the karyotype with 2n = 28 chromosomes were morphologically associated with Proechimys cuvieri, their karyotype shared similarities with those of the same diploid number in two other regions. Although three karyotypes are described for Proechimys cuvieri, no geographic distribution pattern that defined a cline could be identified. Based on the morphological examination of voucher specimens and additional results from molecular analysis, the karyotype with 2n = 46 and FN = 50 could be associated with P. guyannensis.

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

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    Giraldo Cañas Diego

    1998-11-01

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

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

    Science.gov (United States)

    Wilkinson, Justin

    2014-01-01

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

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

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    ECHENIQUE RICARDO O.

    2004-06-01

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

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

    Science.gov (United States)

    Winkelman, Michael

    2005-06-01

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

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

    Science.gov (United States)

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

    2018-01-25

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

  6. USOS DE LAS PALMAS EN LA AMAZONIA COLOMBIANA

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    LAURA MESA

    2013-12-01

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

  7. Marine intervals in Neogene fluvial deposits of western Amazonia

    Science.gov (United States)

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

    2014-05-01

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

  8. Climate Impacts of Deforestation/Land-Use Changes in Central South America in the PRECIS Regional Climate Model: Mean Precipitation and Temperature Response to Present and Future Deforestation Scenarios

    OpenAIRE

    Pablo O. Canziani; Gerardo Carbajal Benitez

    2012-01-01

    Deforestation/land-use changes are major drivers of regional climate change in central South America, impacting upon Amazonia and Gran Chaco ecoregions. Most experimental and modeling studies have focused on the resulting perturbations within Amazonia. Using the Regional Climate Model PRECIS, driven by ERA-40 reanalysis and ECHAM4 Baseline model for the period 1961–2000 (40-year runs), potential effects of deforestation/land-use changes in these and other neighboring ecoregions are evaluated....

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

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    Ana Paula Paes dos Santos

    2014-12-01

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

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

    Directory of Open Access Journals (Sweden)

    S. R. Kolusu

    2015-11-01

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

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

    NARCIS (Netherlands)

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

    2009-01-01

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

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

    Science.gov (United States)

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

    2004-01-01

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

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

    NARCIS (Netherlands)

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

    2004-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-05-01

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

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

    NARCIS (Netherlands)

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

    2010-01-01

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

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

    NARCIS (Netherlands)

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

    2016-01-01

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

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

    NARCIS (Netherlands)

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

    2006-01-01

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

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

    NARCIS (Netherlands)

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

    2016-01-01

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

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

    NARCIS (Netherlands)

    Monsch, KA

    1998-01-01

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

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

    NARCIS (Netherlands)

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

    2010-01-01

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

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

    NARCIS (Netherlands)

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

    2012-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Phil Riris

    2013-02-01

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

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

    Data.gov (United States)

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

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

    Science.gov (United States)

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

    2009-04-01

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

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

    Science.gov (United States)

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

    2014-12-01

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

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

    Science.gov (United States)

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

    2017-08-01

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

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

    Science.gov (United States)

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

    2012-07-01

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

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

    Directory of Open Access Journals (Sweden)

    C. A. O. Vieira

    2012-07-01

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

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

    Science.gov (United States)

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

    2017-03-01

    subvisible cirrus clouds a bimodal distribution with a secondary peak at about 44 sr was found suggesting a mixed composition. A dependence of the lidar ratio with cloud temperature (altitude) was not found, indicating that the clouds are vertically well mixed. The frequency of occurrence of cirrus clouds classified as subvisible (τ 0. 3). Hence, in central Amazonia not only a high frequency of cirrus clouds occurs, but also a large fraction of subvisible cirrus clouds. This high frequency of subvisible cirrus clouds may contaminate aerosol optical depth measured by sun photometers and satellite sensors to an unknown extent.

  10. Territorio y Poder: La reivindicación territorial de los indígenas de la amazonia boliviana

    Directory of Open Access Journals (Sweden)

    Gabriela Canedo Vásquez

    2011-07-01

    Full Text Available El artículo pretende mostrar la centralidad que tiene el territorio y la demanda territorial para los grupos indígenas de la amazonia boliviana. El territorio tiene un papel importante en la reproducción cultural y en la organización política. La investigación se llevó a cabo en la provincia Mojos del departamento del Beni, y muestra que el manejo territorial itinerante y la percepción del territorio que tenían los grupos indígenas se ha transformado a partir del marco estatal –concretamente desde la ley INRA–. Hoy en día los indígenas demandan títulos de propiedad de los espacios ocupados, ante el avasallamiento de los blancos/karayanas. Es así que aquella concepción ilimitada del territorio, propio de los pueblos panindios, se ha transformado, pues en la actualidad los indígenas perciben un territorio limitado, cercado por propiedades privadas. Sin embargo, el territorio al convertirse en una de las demandas centrales de la organización indígena, es el elemento que les permite posicionarse políticamente en un escenario local y nacional.

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

    Directory of Open Access Journals (Sweden)

    Ruben Valbuena

    2008-04-01

    Full Text Available La gran región septentrional de Brasil, la Amazonia, que por varios siglos ha representado un enorme vacío y una potencial fuente de riqueza, ha sido objeto durante el último medio siglo de un acelerado proceso de ocupación y puesta en explotación de forma intensiva. Una dinámica de apropiación apreciable, especialmente, en las tres últimas décadas, cuando la materialización de la red terrestre que ha articulado la margen derecha del gran río facilitó la incursión de los recursos humanos y financieros en el hinterland amazónico.Una red que ha reestructurado el espacio regional, al que daba sentido la malla fluvial y la débil red de lugares, configurada por los núcleos de población surgidos en las orillas de los cauces. Santarém, una ciudad histórica con una localización estratégica entre los dos mayores centros urbanos amazónicos, ha sido palco de enormes transformaciones desde la construcción de las carreteras, pues ligada mediante la Cuibá-Santarém al Centro Oeste de Brasil y a través de la Transamazônica al Nordeste brasileño y a la Amazonia Occidental ha pasado a desempeñar un importante papel como nexo articulador en la región Norte. Al mismo tiempo, se erige como el principal asentamiento humano de esta vasta región central, dirigiendo un proceso emergente de construcción regional.La grande région septentrionale du Brésil, l'Amazonie, qui durant plusieurs siècles n’a représenté qu’un énorme vide et une source de richesse potentielle, a fait l'objet pendant le dernier demi-siècle d'un processus accéléré d’occupation et d’une mise en exploitation intensive. Une forte dynamique d'appropriation a facilité l'incursion de nouvelles ressources humaines et financières dans l’hinterland amazonien, spécialement au cours des trois dernières décennies, quand la réalisation d’un réseau terrestre a articulé la rive droite de la grande rivière.Ce réseau a restructuré l'espace r

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

    Science.gov (United States)

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

    2008-05-01

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

  13. Anthropogenic Emissions Change the Amount and Composition of Organic PM1 in Amazonia

    Science.gov (United States)

    de Sá, S. S.; Palm, B. B.; Campuzano Jost, P.; Day, D. A.; Hu, W.; Isaacman-VanWertz, G. A.; Yee, L.; Wernis, R. A.; Thalman, R.; Brito, J.; Carbone, S.; Artaxo, P.; Goldstein, A. H.; Manzi, A. O.; Souza, R. A. F. D.; Wang, J.; Alexander, M. L. L.; Jimenez, J. L.; Martin, S. T.

    2017-12-01

    The Amazon forest, while one of the few regions on the globe where pristine conditions may still prevail, has experienced rapid changes due to increasing urbanization in the past decades. Manaus, a Brazilian city of 2-million people in the central Amazon basin, releases a pollution plume over the forest, potentially affecting the production pathways of particulate matter (PM) in the region. As part of GoAmazon2014/5, a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) and a suite of other gas and particle-phase instruments were deployed at the T3 research site, 70 km downwind of Manaus, during the wet and dry seasons. Through a combination of meteorology, emissions, and chemistry, the T3 site was affected by a mixture of biogenic emissions from the tropical rainforest, urban outflow from the Manaus metropolitan area and biomass burning plumes. Results from the T3 site are presented in the context of measurements at T0a/T0t and T2, sites representing predominantly clean and polluted conditions, respectively. The organic component consistently represented on average 70-80% of the PM1 mass concentration across sites and seasons, and constitutes the focus of this work. Positive matrix factorization (PMF) analysis was applied to the time series of organic mass spectra. The resulting factors, which included the so-called IEPOX-SOA, MO-OOA, LO-OOA, BBOA, Fac91 and HOA, provide information on the relative contributions of different sources and pathways to organic PM production. In addition, Fuzzy c-means clustering was applied to the time series of pollution indicators, including concentrations of NOy, total particle number, ozone and sulfate, in order to better understand the convoluted influences of different processes and airmass origin to each point in time. Through combination of the PMF and Fuzzy c-means analyses, insights are drawn about the relative composition of organic PM1 at varying degrees of influence of biogenic and anthropogenic

  14. Mayaro virus infection in amazonia: a multimodel inference approach to risk factor assessment.

    Directory of Open Access Journals (Sweden)

    Fernando Abad-Franch

    Full Text Available BACKGROUND: Arboviral diseases are major global public health threats. Yet, our understanding of infection risk factors is, with a few exceptions, considerably limited. A crucial shortcoming is the widespread use of analytical methods generally not suited for observational data--particularly null hypothesis-testing (NHT and step-wise regression (SWR. Using Mayaro virus (MAYV as a case study, here we compare information theory-based multimodel inference (MMI with conventional analyses for arboviral infection risk factor assessment. METHODOLOGY/PRINCIPAL FINDINGS: A cross-sectional survey of anti-MAYV antibodies revealed 44% prevalence (n = 270 subjects in a central Amazon rural settlement. NHT suggested that residents of village-like household clusters and those using closed toilet/latrines were at higher risk, while living in non-village-like areas, using bednets, and owning fowl, pigs or dogs were protective. The "minimum adequate" SWR model retained only residence area and bednet use. Using MMI, we identified relevant covariates, quantified their relative importance, and estimated effect-sizes (β ± SE on which to base inference. Residence area (β(Village  =  2.93 ± 0.41; β(Upland = -0.56 ± 0.33, β(Riverbanks  =  -2.37 ± 0.55 and bednet use (β = -0.95 ± 0.28 were the most important factors, followed by crop-plot ownership (β  =  0.39 ± 0.22 and regular use of a closed toilet/latrine (β = 0.19 ± 0.13; domestic animals had insignificant protective effects and were relatively unimportant. The SWR model ranked fifth among the 128 models in the final MMI set. CONCLUSIONS/SIGNIFICANCE: Our analyses illustrate how MMI can enhance inference on infection risk factors when compared with NHT or SWR. MMI indicates that forest crop-plot workers are likely exposed to typical MAYV cycles maintained by diurnal, forest dwelling vectors; however, MAYV might also be circulating in nocturnal, domestic-peridomestic cycles

  15. Regional N2O fluxes in Amazonia derived from aircraft vertical profiles

    Science.gov (United States)

    D'Amelio, M. T. S.; Gatti, L. V.; Miller, J. B.; Tans, P.

    2009-11-01

    Nitrous oxide (N2O) is the third most important anthropogenic greenhouse gas. Globally, the main sources of N2O are nitrification and denitrification in soils. About two thirds of the soil emissions occur in the tropics and approximately 20% originate in wet rainforest ecosystems, like the Amazon forest. The work presented here involves aircraft vertical profiles of N2O from the surface to 4 km over two sites in the Eastern and Central Amazon: Tapajós National Forest (SAN) and Cuieiras Biologic Reserve (MAN), and the estimation of N2O fluxes for regions upwind of these sites. To our knowledge, these regional scale N2O measurements in Amazonia are unique and represent a new approach to looking regional scale emissions. The fluxes upwind of MAN exhibited little seasonality, and the annual mean was 2.1±1.0 mg N2O m-2 day-1, higher than that for fluxes upwind of SAN, which averaged 1.5±1.6 mg N2O m-2 day-1. The higher rainfall around the MAN site could explain the higher N2O emissions, as a result of increased soil moisture accelerating microbial nitrification and denitrification processes. For fluxes from the coast to SAN seasonality is present for all years, with high fluxes in the months of March through May, and in November through December. The first peak of N2O flux is strongly associated with the wet season. The second peak of high N2O flux recorded at SAN occurs during the dry season and can not be easily explained. However, about half of the dry season profiles exhibit significant correlations with CO, indicating a larger than expected source of N2O from biomass burning. The average CO:N2O ratio for all profiles sampled during the dry season is 94±77 mol CO:mol N2O and suggests a larger biomass burning contribution to the global N2O budget than previously reported.

  16. Secondary organic aerosol formation from ambient air in an oxidation flow reactor in central Amazonia

    Science.gov (United States)

    Palm, Brett B.; de Sá, Suzane S.; Day, Douglas A.; Campuzano-Jost, Pedro; Hu, Weiwei; Seco, Roger; Sjostedt, Steven J.; Park, Jeong-Hoo; Guenther, Alex B.; Kim, Saewung; Brito, Joel; Wurm, Florian; Artaxo, Paulo; Thalman, Ryan; Wang, Jian; Yee, Lindsay D.; Wernis, Rebecca; Isaacman-VanWertz, Gabriel; Goldstein, Allen H.; Liu, Yingjun; Springston, Stephen R.; Souza, Rodrigo; Newburn, Matt K.; Lizabeth Alexander, M.; Martin, Scot T.; Jimenez, Jose L.

    2018-01-01

    Secondary organic aerosol (SOA) formation from ambient air was studied using an oxidation flow reactor (OFR) coupled to an aerosol mass spectrometer (AMS) during both the wet and dry seasons at the Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) field campaign. Measurements were made at two sites downwind of the city of Manaus, Brazil. Ambient air was oxidized in the OFR using variable concentrations of either OH or O3, over ranges from hours to days (O3) or weeks (OH) of equivalent atmospheric aging. The amount of SOA formed in the OFR ranged from 0 to as much as 10 µg m-3, depending on the amount of SOA precursor gases in ambient air. Typically, more SOA was formed during nighttime than daytime, and more from OH than from O3 oxidation. SOA yields of individual organic precursors under OFR conditions were measured by standard addition into ambient air and were confirmed to be consistent with published environmental chamber-derived SOA yields. Positive matrix factorization of organic aerosol (OA) after OH oxidation showed formation of typical oxidized OA factors and a loss of primary OA factors as OH aging increased. After OH oxidation in the OFR, the hygroscopicity of the OA increased with increasing elemental O : C up to O : C ˜ 1.0, and then decreased as O : C increased further. Possible reasons for this decrease are discussed. The measured SOA formation was compared to the amount predicted from the concentrations of measured ambient SOA precursors and their SOA yields. While measured ambient precursors were sufficient to explain the amount of SOA formed from O3, they could only explain 10-50 % of the SOA formed from OH. This is consistent with previous OFR studies, which showed that typically unmeasured semivolatile and intermediate volatility gases (that tend to lack C = C bonds) are present in ambient air and can explain such additional SOA formation. To investigate the sources of the unmeasured SOA-forming gases during this campaign, multilinear regression analysis was performed between measured SOA formation and the concentration of gas-phase tracers representing different precursor sources. The majority of SOA-forming gases present during both seasons were of biogenic origin. Urban sources also contributed substantially in both seasons, while biomass burning sources were more important during the dry season. This study enables a better understanding of SOA formation in environments with diverse emission sources.

  17. Density, size and distribution of stomata in 35 rainforest trees species in Central Amazonia

    OpenAIRE

    Miguel Angelo Branco Camargo; Ricardo Antonio Marenco

    2011-01-01

    Stomata are turgor-operated valves that control water loss and CO2 uptake during photosynthesis, and thereby water relation and plant biomass accumulation is closely related to stomatal functioning. The aims of this work were to document how stomata are distributed on the leaf surface and to determine if there is any significant variation in stomatal characteristics among Amazonian tree species, and finally to study the relationship between stomatal density (S D) and tree height. Thirty five ...

  18. Density, size and distribution of stomata in 35 rainforest tree species in Central Amazonia

    OpenAIRE

    Camargo, Miguel Angelo Branco; Marenco, Ricardo Antonio

    2011-01-01

    Stomata are turgor-operated valves that control water loss and CO2 uptake during photosynthesis, and thereby water relation and plant biomass accumulation is closely related to stomatal functioning. The aims of this work were to document how stomata are distributed on the leaf surface and to determine if there is any significant variation in stomatal characteristics among Amazonian tree species, and finally to study the relationship between stomatal density (S D) and tree height. Thirty five ...

  19. Soil Co2 efflux in central Amazonia: Environmental and methodological effects

    NARCIS (Netherlands)

    Zanchi, F.B.; Waterloo, M.J.; Kruijt, B.; Kesselmeier, J.; Luizao, F.J.; Manzi, A.O.; Dolman, A.J.

    2012-01-01

    Soil respiration plays a significant role in the carbon cycle of Amazonian rainforests. Measurements of soil respiration have only been carried out in few places in the Amazon. This study investigated the effects of the method of ring insertion in the soil as well as of rainfall and spatial

  20. Preliminary Compositional Evidence of Provenance of Ceramics from Hatahara Archaeological Site, Central Amazonia

    Directory of Open Access Journals (Sweden)

    K. P. Nunes

    2013-01-01

    Full Text Available One hundred twenty four ceramic fragments and six clay samples from the Hatahara archaeological site in Amazonas state, Brazil, were analyzed using instrumental neutron activation analysis, INAA, to determine the concentration of twenty chemical elements: Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Nd, Rb, Sc, Ta, Tb, Th, U, Yb, and Zn. The dataset was submitted to multivariate statistical analysis. The classification was done by cluster analysis and discriminant analysis. The results demonstrated the occurrence of four different groups of ceramics, which represent three archaeological phases: Paredão, Manacapuru, and Guarita. This data is consistent with previous traditional petrographic examination of the ceramic samples. Based on probability measures, the great majority of the ceramics are considered to be local in origin.

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

    NARCIS (Netherlands)

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

    2015-01-01

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

  2. Floristic composition and community structure of epiphytic angiosperms in a terra firme forest in central Amazonia

    Directory of Open Access Journals (Sweden)

    Mariana Victória Irume

    2013-06-01

    Full Text Available This survey aimed to describe the floristic composition and structure of the epiphytic community occurring in a terra firme forest in the city of Coari, Brazil, in the Amazon region. Data collection was performed with a 1.5 ha plot method, with which upland, slope and lowland habitats were sampled. All angiosperm epiphytes and their host plants (diameter at breast height > 10 cm were sampled. We recorded 3.528 individuals in 13 families, 48 genera and 164 species. Araceae was the most prevalent family with regard to the importance value and stood out in all related parameters, followed by Bromeliaceae, Cyclanthaceae and Orchidaceae. The species with the highest epiphytic importance values were Guzmania lingulata (L. Mez. and Philodendron linnaei Kunth. The predominant life form was hemiepiphytic. Estimated floristic diversity was 3.2 (H'. The studied epiphytic community was distributed among 727 host plants belonging to 40 families, 123 genera and 324 species. One individual of Guarea convergens T.D. Penn. was the host with the highest richness and abundance of epiphytes. Stems/trunks of host plants were the most colonized segments, and the most favorable habitat for epiphytism was the lowlands, where 84.1% of species and 48.2% of epiphytic specimens were observed.

  3. Historical human footprint on modern tree species composition in the Purus-Madeira interfluve, central Amazonia.

    Directory of Open Access Journals (Sweden)

    Carolina Levis

    Full Text Available BACKGROUND: Native Amazonian populations managed forest resources in numerous ways, often creating oligarchic forests dominated by useful trees. The scale and spatial distribution of forest modification beyond pre-Columbian settlements is still unknown, although recent studies propose that human impact away from rivers was minimal. We tested the hypothesis that past human management of the useful tree community decreases with distance from rivers. METHODOLOGY/PRINCIPAL FINDINGS: In six sites, we inventoried trees and palms with DBH≥10 cm and collected soil for charcoal analysis; we also mapped archaeological evidence around the sites. To quantify forest manipulation, we measured the relative abundance, richness and basal area of useful trees and palms. We found a strong negative exponential relationship between forest manipulation and distance to large rivers. Plots located from 10 to 20 km from a main river had 20-40% useful arboreal species, plots between 20 and 40 km had 12-23%, plots more than 40 km had less than 15%. Soil charcoal abundance was high in the two sites closest to secondary rivers, suggesting past agricultural practices. The shortest distance between archaeological evidence and plots was found in sites near rivers. CONCLUSIONS/SIGNIFICANCE: These results strongly suggest that past forest manipulation was not limited to the pre-Columbian settlements along major rivers, but extended over interfluvial areas considered to be primary forest today. The sustainable use of Amazonian forests will be most effective if it considers the degree of past landscape domestication, as human-modified landscapes concentrate useful plants for human sustainable use and management today.

  4. Temporal variation in black-caiman-nest predation in varzea of central Brazilian amazonia.

    Science.gov (United States)

    Torralvo, Kelly; Botero-Arias, Robinson; Magnusson, William E

    2017-01-01

    On the Amazon floodplain, the main predators of black caiman (Melanosuchus niger) eggs are jaguars (Panthera onca), tegu lizards (Tupinambis teguixim), capuchin monkeys (Sapajus macrocephalus) and humans (Homo sapiens). In this study, we investigated the relationship between predator attacks on nests and incubation period, and evaluated the influence of initial predation on subsequent predation in the Mamirauá Sustainable Development Reserve. We also evaluated the influence of presence of females near the nests and manipulation of nests on the occurrence of attacks. We compared results from data obtained with camera traps and vestiges left by predators on estimates of rates of predation by different predators. Egg predation was recorded in 32% of the 658 black caiman nests monitored during two years. Our results suggest that the probability of predation on black caiman eggs is relatively constant throughout the incubation period and that predation on eggs was lower when adults, presumably females, were present. Careful opening of nests and handling of eggs did not increase the number of attacks on black caiman nests. Nest opening by a predator appeared to increase the chances of a subsequent attack because most of the attacks on nests occurred soon after a predator first opened the nest. However, attacks by another species of predator do not appear to be necessary to initiate attacks by any other species of predator. Results based on camera traps and vestiges differed, but use of vestiges was adequate for identifying the principal predators on eggs in black caiman nests and, in many circumstances, the vestiges may be better for estimating predation by humans. In this study, opening nests and handling eggs did not increase the number of attacks on black caiman nests.

  5. Temporal variation in black-caiman-nest predation in varzea of central Brazilian amazonia.

    Directory of Open Access Journals (Sweden)

    Kelly Torralvo

    Full Text Available On the Amazon floodplain, the main predators of black caiman (Melanosuchus niger eggs are jaguars (Panthera onca, tegu lizards (Tupinambis teguixim, capuchin monkeys (Sapajus macrocephalus and humans (Homo sapiens. In this study, we investigated the relationship between predator attacks on nests and incubation period, and evaluated the influence of initial predation on subsequent predation in the Mamirauá Sustainable Development Reserve. We also evaluated the influence of presence of females near the nests and manipulation of nests on the occurrence of attacks. We compared results from data obtained with camera traps and vestiges left by predators on estimates of rates of predation by different predators. Egg predation was recorded in 32% of the 658 black caiman nests monitored during two years. Our results suggest that the probability of predation on black caiman eggs is relatively constant throughout the incubation period and that predation on eggs was lower when adults, presumably females, were present. Careful opening of nests and handling of eggs did not increase the number of attacks on black caiman nests. Nest opening by a predator appeared to increase the chances of a subsequent attack because most of the attacks on nests occurred soon after a predator first opened the nest. However, attacks by another species of predator do not appear to be necessary to initiate attacks by any other species of predator. Results based on camera traps and vestiges differed, but use of vestiges was adequate for identifying the principal predators on eggs in black caiman nests and, in many circumstances, the vestiges may be better for estimating predation by humans. In this study, opening nests and handling eggs did not increase the number of attacks on black caiman nests.

  6. PEDO-TRANSFER FUNCTIONS FOR ESTIMATING SOIL BULK DENSITY IN CENTRAL AMAZONIA

    Directory of Open Access Journals (Sweden)

    Henrique Seixas Barros

    2015-04-01

    Full Text Available Under field conditions in the Amazon forest, soil bulk density is difficult to measure. Rigorous methodological criteria must be applied to obtain reliable inventories of C stocks and soil nutrients, making this process expensive and sometimes unfeasible. This study aimed to generate models to estimate soil bulk density based on parameters that can be easily and reliably measured in the field and that are available in many soil-related inventories. Stepwise regression models to predict bulk density were developed using data on soil C content, clay content and pH in water from 140 permanent plots in terra firme (upland forests near Manaus, Amazonas State, Brazil. The model results were interpreted according to the coefficient of determination (R2 and Akaike information criterion (AIC and were validated with a dataset consisting of 125 plots different from those used to generate the models. The model with best performance in estimating soil bulk density under the conditions of this study included clay content and pH in water as independent variables and had R2 = 0.73 and AIC = -250.29. The performance of this model for predicting soil density was compared with that of models from the literature. The results showed that the locally calibrated equation was the most accurate for estimating soil bulk density for upland forests in the Manaus region.

  7. Secondary organic aerosol formation from ambient air in an oxidation flow reactor in central Amazonia

    Directory of Open Access Journals (Sweden)

    B. B. Palm

    2018-01-01

    Full Text Available Secondary organic aerosol (SOA formation from ambient air was studied using an oxidation flow reactor (OFR coupled to an aerosol mass spectrometer (AMS during both the wet and dry seasons at the Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5 field campaign. Measurements were made at two sites downwind of the city of Manaus, Brazil. Ambient air was oxidized in the OFR using variable concentrations of either OH or O3, over ranges from hours to days (O3 or weeks (OH of equivalent atmospheric aging. The amount of SOA formed in the OFR ranged from 0 to as much as 10 µg m−3, depending on the amount of SOA precursor gases in ambient air. Typically, more SOA was formed during nighttime than daytime, and more from OH than from O3 oxidation. SOA yields of individual organic precursors under OFR conditions were measured by standard addition into ambient air and were confirmed to be consistent with published environmental chamber-derived SOA yields. Positive matrix factorization of organic aerosol (OA after OH oxidation showed formation of typical oxidized OA factors and a loss of primary OA factors as OH aging increased. After OH oxidation in the OFR, the hygroscopicity of the OA increased with increasing elemental O : C up to O : C ∼ 1.0, and then decreased as O : C increased further. Possible reasons for this decrease are discussed. The measured SOA formation was compared to the amount predicted from the concentrations of measured ambient SOA precursors and their SOA yields. While measured ambient precursors were sufficient to explain the amount of SOA formed from O3, they could only explain 10–50 % of the SOA formed from OH. This is consistent with previous OFR studies, which showed that typically unmeasured semivolatile and intermediate volatility gases (that tend to lack C = C bonds are present in ambient air and can explain such additional SOA formation. To investigate the sources of the unmeasured SOA-forming gases during this campaign, multilinear regression analysis was performed between measured SOA formation and the concentration of gas-phase tracers representing different precursor sources. The majority of SOA-forming gases present during both seasons were of biogenic origin. Urban sources also contributed substantially in both seasons, while biomass burning sources were more important during the dry season. This study enables a better understanding of SOA formation in environments with diverse emission sources.

  8. Growth, leaf and stomatal traits of crabwood (Carapa guianensis Aubl. in central Amazonia

    Directory of Open Access Journals (Sweden)

    Miguel Angelo Branco Camargo

    2012-02-01

    Full Text Available Crabwood (Carapa guianensis Aubl. is a fast growing tree species with many uses among Amazonian local communities. The main objective of this study was to assess the effect of seasonal rainfall pattern on growth rates, and seasonal and diurnal changes in leaf gas exchange and leaf water potential (ΨL in crabwood. To assess the effect of rainfall seasonality on growth and physiological leaf traits an experiment was conducted in Manaus, AM (03º 05' 30" S, 59º 59' 35" S. In this experiment, six 6-m tall plants were used to assess photosynthetic traits and ΨL. In a second experiment the effect of growth irradiance on stomatal density (S D, size (S S and leaf thickness was assessed in 0.8-m tall saplings. Stomatal conductance (g s and light-saturated photosynthesis (Amax were higher in the wet season, and between 09:00 and 15:00 h. However, no effect of rainfall seasonality was found on ΨL and potential photosynthesis (CO2-saturated. ΨL declined from -0.3 MPa early in the morning to -0.75 MPa after midday. It increased in the afternoon but did not reach full recovery at sunset. Growth rates of crabwood were high, and similar in both seasons (2 mm month-1. Leaf thickness and S D were 19% and 47% higher in sun than in shade plants, whereas the opposite was true for S S. We conclude that ΨL greatly affects carbon assimilation of crabwood by reducing g s at noon, although this effect is not reflected on growth rates indicating that other factors offset the effect of g s on Amax.

  9. Damage of camu-camu (Myrciaria dubia) fruits by Conotrachelus dubiae (Coleoptera: curculionidae) in Central Amazonia

    OpenAIRE

    Ferreira, Sidney Alberto do Nascimento; Gentil, Daniel Felipe de Oliveira; Silva, Neliton Marques da

    2003-01-01

    No Brasil, a ocorrência de Conotrachelus dubiae O'Brien, 1995 (Coleoptera: Curculionidae) em camu-camu [Myrciaria dubia (H.B.K.) McVaugh, Myrtaceae] tinha sido constatada somente em populações naturais. Relata-se sua ocorrência em um cultivo experimental, onde se avaliou os danos de C. dubiae em frutos de camu-camu, em diferentes graus de amadurecimento, entre 1999 e 2003. Os danos causados pela larva aumentaram com o amadurecimento dos frutos, havendo maior comprometimento da polpa do fruto ...

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

    Directory of Open Access Journals (Sweden)

    Julissa Roncal

    2014-05-01

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

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

    Directory of Open Access Journals (Sweden)

    Thiago Vasconcelos dos Santos

    2014-04-01

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

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

    OpenAIRE

    Philip M. Fearnside

    2008-01-01

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

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

    Science.gov (United States)

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

    2003-01-01

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

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

    OpenAIRE

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

    2004-01-01

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

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

    Science.gov (United States)

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

    2008-05-27

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

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

    Science.gov (United States)

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

    2013-06-22

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

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

    Science.gov (United States)

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

    2010-04-27

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

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

    Science.gov (United States)

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

    2014-07-22

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

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

    Science.gov (United States)

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

    2011-12-01

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

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

    Directory of Open Access Journals (Sweden)

    Flávio Bezerra Barros

    2009-06-01

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

  1. Kinship and Social Behavior of Lowland Tapirs (Tapirus terrestris) in a Central Amazon Landscape

    Science.gov (United States)

    Pinho, Gabriela M.; Gonçalves da Silva, Anders; Hrbek, Tomas; Venticinque, Eduardo M.; Farias, Izeni P.

    2014-01-01

    We tested the hypothesis that tapirs tolerate individuals from adjacent and overlapping home ranges if they are related. We obtained genetic data from fecal samples collected in the Balbina reservoir landscape, central Amazon. Samples were genotyped at 14 microsatellite loci, of which five produced high quality informative genotypes. Based on an analysis of 32 individuals, we inferred a single panmictic population with high levels of heterozygosity. Kinship analysis identified 10 pairs of full siblings or parent-offspring, 10 pairs of half siblings and 25 unrelated pairs. In 10 cases, the related individuals were situated on opposite margins of the reservoir, suggesting that tapirs are capable of crossing the main river, even after damming. The polygamous model was the most likely mating system for Tapirus terrestris. Moran's I index of allele sharing between pairs of individuals geographically close (3 km). Confirming this result, the related individuals were not geographically closer than unrelated ones (W = 188.5; p = 0.339). Thus, we found no evidence of a preference for being close to relatives and observed a tendency for dispersal. The small importance of relatedness in determining spatial distribution of individuals is unusual in mammals, but not unheard of. Finally, non-invasive sampling allowed efficient access to the genetic data, despite the warm and humid climate of the Amazon, which accelerates DNA degradation. PMID:24671057

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

    Science.gov (United States)

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

    2002-01-01

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

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

    NARCIS (Netherlands)

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

    2013-01-01

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

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

    NARCIS (Netherlands)

    Garavello, Julio Cesar; Santos, dos Geraldo Mendes

    1992-01-01

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

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

    Directory of Open Access Journals (Sweden)

    C. Buendía

    2018-01-01

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

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

    Science.gov (United States)

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

    2013-06-05

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

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Science.gov (United States)

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

    2016-06-24

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

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

    Science.gov (United States)

    Suarez, L.; Kruijt, B.

    2007-05-01

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

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

    Science.gov (United States)

    Rastogi, D.; Baidya Roy, S.

    2011-12-01

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

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

    Directory of Open Access Journals (Sweden)

    N. Galia Selaya

    2017-06-01

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

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

    Science.gov (United States)

    Nepstad, Daniel C.

    1997-01-01

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

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

    Science.gov (United States)

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

    2017-12-01

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

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

    International Nuclear Information System (INIS)

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

    1991-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Sérgio Luiz Bessa Luz

    2014-07-01

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

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

    Science.gov (United States)

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

    2017-12-31

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

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

    Science.gov (United States)

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

    2018-01-01

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

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

    Science.gov (United States)

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

    2017-10-01

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

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

    Science.gov (United States)

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

    2015-02-01

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

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

    Directory of Open Access Journals (Sweden)

    Miquéias Ferrão

    2017-10-01

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

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

    Directory of Open Access Journals (Sweden)

    Madelin Rodríguez Rensoli

    2017-08-01

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

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

    Directory of Open Access Journals (Sweden)

    Eric Atlas Davidson

    2008-12-01

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

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

    Science.gov (United States)

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

    2013-06-05

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

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

    Science.gov (United States)

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

    2014-10-01

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

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

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

    2008-05-27

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

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

    Directory of Open Access Journals (Sweden)

    Condamine Fabien L

    2012-06-01

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

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

    Science.gov (United States)

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

    2012-06-12

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

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

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

    2011-12-01

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

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

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    U. Rummel

    2007-10-01

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

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

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

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    Marengo, J. A.

    2015-12-01

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

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

    Science.gov (United States)

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

    2014-01-01

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

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

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

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

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

    Directory of Open Access Journals (Sweden)

    Fabíola Poletto

    2005-12-01

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

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

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    Jorge Iván Sánchez-Botero

    2010-12-01

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

  15. Changes in the physico-chemical properties of Amazonian aerosols from background conditions due to urban impacts in Central Amazonia.

    Science.gov (United States)

    Artaxo, P.; Barbosa, H. M.; Brito, J.; Carbone, S.; Fiorese, C.; Andre, B.; Rizzo, L. V.; Ditas, F.; Pöhlker, C.; Pöhlker, M. L.; Saturno, J.; Holanda, B. A.; Wang, J.; Souza, R. A. F. D.; Machado, L.; Andreae, M. O.; Martin, S. T.

    2016-12-01

    The GoAmazon 2014/15 experiment (Observations and Modeling of the Green Ocean Amazon) was a great opportunity to study how urbanization can change aerosol properties under pristine conditions in a tropical rain forest. The experiment took place from January 2014 to December 2015 in the vicinity of Manaus, Brazil, where several sampling stations were operated. Natural biogenic aerosol properties were studied in 3 sampling stations upwind of Manaus (ATTO (T0a), ZF2 (T0z) and EMBRAPA (T0e)). Urban impacted aerosols were analysed in two downwind sampling stations at Tiwa (T2) and Manacapuru (T3). Properties analysed were size distribution, scattering and absorption, composition, vertical profiles and others. Remote sensing measurements were done using AERONET and MODIS, while extensive ground based measurements were done in all sampling stations. Remote sensing measurements shows important changes in aerosol optical depth (AOD), especially in the aerosol absorption component. It was also observed a reduction in cloud droplet size downwind of Manaus for liquid phase clouds. Changes in particle number and size were also very significant, that reflected in changes in the aerosol radiative forcing (RF) before and after Manaus plume. In the dry season, an average RF of -24 w/m² was observed upwind, while -17 w/m² was observed downwind, due to large scale biomass burning aerosols. Single scattering albedo (SSA) at 550 nm changed from a high value of 0.96 upwind to 0.84 downwind due to the increase in absorbing aerosols in the wet season. In the dry season, SSA at 550nm changed from 0.95 to 0.87. Aerosol composition showed a large dominance of organic aerosols for all sites, accounting for 65-75% of PM1 non refractory aerosol. Most of these were secondary organic aerosol (SOA), with very low sulfate and nitrate concentrations. The influence of the Manaus plume on aerosol properties was more intense during the wet season, because in the dry season a significant amount of large scale biomass burning aerosol was observed for all GoAmazon 2014/15 sites.

  16. The igapó of the Negro River in central Amazonia: Linking late-successional inundation forest with fluvial geomorphology

    Science.gov (United States)

    Montero, Juan Carlos; Latrubesse, Edgardo M.

    2013-10-01

    Despite important progress on Amazonian floodplain research, the flooded forest of the Negro River "igapó" has been little investigated. In particular, no study has previously focused the linkage between fluvial geomorphology and the floristic variation across the course of the river. In this paper we describe and interpret relations between igapó forest, fluvial geomorphology and the spatial evolution of the igapó forest through the Holocene. Therefore, we investigate the effect of geomorphological units of the floodplain and channel patterns on tree diversity, composition and structural parameters of the late-successional igapó forest. Our results show that sites sharing almost identical flooding regime, exhibit variable tree assemblages, species richness and structural parameters such as basal area, tree density and tree heights, indicating a trend in which the geomorphologic styles seem to partially control the organization of igapó's tree communities. This can be also explained by the high variability of well-developed geomorphologic units in short distances and concentrated in small areas. In this dynamic the inputs from the species pool of tributary rivers play a crucial role, but also the depositional and erosional processes associated with the evolution of the floodplain during the Holocene may control floristic and structural components of the igapó forests. These results suggest that a comprehensive approach integrating floristic and geomorphologic methods is needed to understand the distribution of the complex vegetation patterns in complex floodplains such as the igapó of the Negro River. This combination of approaches may introduce a better comprehension of the temporal and spatial evolutionary analysis and a logic rationale to understand the vegetation distribution and variability in function of major landforms, soil distributions and hydrology. Thus, by integrating the past into macroecological analyses will sharpen our understanding of the underlying forces for contemporary floristic patterns along the inundation forests of the Negro River.

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

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    Mariana Gomes Germano

    2012-05-01

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

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

    Science.gov (United States)

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

    2009-12-01

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

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

    Science.gov (United States)

    Schneider, Maurício; Peres, Carlos A

    2015-01-01

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

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

    Science.gov (United States)

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

    2011-11-01

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

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

    Science.gov (United States)

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

    2016-02-01

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

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

    Science.gov (United States)

    Darskaia, N F; Malygin, V M

    1996-01-01

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

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

    Directory of Open Access Journals (Sweden)

    R. Poccard Chapuis

    2007-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Risto Kalliola

    2011-01-01

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

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

    Directory of Open Access Journals (Sweden)

    DARCILÉA F. CASTRO

    2013-03-01

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

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

    International Nuclear Information System (INIS)

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

    2014-01-01

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

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

    International Nuclear Information System (INIS)

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

    2011-01-01

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

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

    International Nuclear Information System (INIS)

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

    2011-01-01

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

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

    Science.gov (United States)

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

    2015-01-01

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

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

    International Nuclear Information System (INIS)

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

    2017-01-01

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

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

    Directory of Open Access Journals (Sweden)

    José Ignacio Ruiz-Sanz

    2012-05-01

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

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

    Science.gov (United States)

    2015-01-01

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

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Mark A Higgins

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

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

    Directory of Open Access Journals (Sweden)

    Christine Padoch

    2008-12-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-11-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-07-15

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

  18. Partnership inside Governance Spaces: the case of the Municipal Development Forum of Igarapé-Açú, Pará, Amazonia

    Directory of Open Access Journals (Sweden)

    Mário Vasconcellos Sobrinho

    Full Text Available Abstract This paper discusses how partnership between local organisations and Government inside governance spaces affects local development. The aim is to raise some critical issues about the concept of partnership and about partnership effectively for municipal development. Thus, the article uses partnership as its central theory. Specifically, it explores to what extent partnership is an effective strategy for local development in areas of historical conflict between local Government and local organisations in Pará State, Brazilian Amazonia. It focuses particularly on the municipality of Igarapé-Açú, located in north-east of Pará State. Igarapé-Açú was chosen because it is a singular case of local organisations and Government partnership since 2008 when a governance space was created to carry out a partnership process called Municipal Development Forum (MDF. Methodologically, the case study was carried out from a qualitative analysis with data gathered from documents and semi-structured interviews with key-informants. The paper shows that the great challenge to build partnerships between local Government and local organisations is not in these actors capacity to represent the state and civil society in a governance forum, but in their capacity to change the local institutional environment to enable this forum to propose changes in terms of rural development. The paper shows that institutional change does not happen rapidly; changes depend on a particular historical context. In conclusion, the case of Igarapé-Açú shows that in an environment where there is great political conflict much time is needed to create links between the rural actors.

  19. Fenologia de Cornops aquaticum (Orthoptera: Acrididae associado a Eichhornia crassipes (Pontederiaceae em um Lago de Várzea na Amazônia Central, Brasil

    Directory of Open Access Journals (Sweden)

    Carlos Elias BRAGA

    2011-01-01

    Full Text Available La tucura Neotropical, Cornops aquaticum (Bruner, vive asociada a las macrófitas de la familia Pontederiaceae, de las cuales se alimenta. En los lagos de la Amazonia Central, Eichhornia crassipes (Mart. Solms (camalote o aguape constituye la planta huésped más importante de esta tucura. El objetivo de este trabajo fue estudiar la fenología de los adultos y las ninfas de C. aquaticum en los camalotales de E. crassipes, en relación al régimen hidrológico de la Amazonia Central. Los muestreos se realizaron entre los meses de abril de 2006 a agosto de 2007, en el Lago Camaleón (03o17’05”S 60o11’11”O en la Várzea de la Amazonia Central. Los individuos fueron capturados desde una embarcación a motor, utilizando una red entomológica de 70 cm de diámetro. Durante este estudio, se capturaron un total de 850 ejemplares (296 adultos y 554 ninfas. Se observó que la abundancia y la biomasa de los adultos y de las ninfas de C. aquaticum, así como la planta huésped, están estrechamente relacionados con la oscilación estacional del nivel del río (pulso de inundación.

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

    Directory of Open Access Journals (Sweden)

    Charles R Clement

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

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

    Science.gov (United States)

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

    2009-01-01

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

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

    International Nuclear Information System (INIS)

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

    2005-01-01

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

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

    OpenAIRE

    Francisco Azuero; Jorge Armando Rodríguez

    2016-01-01

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

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

    OpenAIRE

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

    2008-01-01

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

  5. Microsatellite data suggest significant population structure and differentiation within the malaria vector Anopheles darlingi in Central and South America

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    Achee Nicole L

    2008-03-01

    Full Text Available Abstract Background Anopheles darlingi is the most important malaria vector in the Neotropics. An understanding of A. darlingi's population structure and contemporary gene flow patterns is necessary if vector populations are to be successfully controlled. We assessed population genetic structure and levels of differentiation based on 1,376 samples from 31 localities throughout the Peruvian and Brazilian Amazon and Central America using 5–8 microsatellite loci. Results We found high levels of polymorphism for all of the Amazonian populations (mean RS = 7.62, mean HO = 0.742, and low levels for the Belize and Guatemalan populations (mean RS = 4.3, mean HO = 0.457. The Bayesian clustering analysis revealed five population clusters: northeastern Amazonian Brazil, southeastern and central Amazonian Brazil, western and central Amazonian Brazil, Peruvian Amazon, and the Central American populations. Within Central America there was low non-significant differentiation, except for between the populations separated by the Maya Mountains. Within Amazonia there was a moderate level of significant differentiation attributed to isolation by distance. Within Peru there was no significant population structure and low differentiation, and some evidence of a population expansion. The pairwise estimates of genetic differentiation between Central America and Amazonian populations were all very high and highly significant (FST = 0.1859 – 0.3901, P DA and FST distance-based trees illustrated the main division to be between Central America and Amazonia. Conclusion We detected a large amount of population structure in Amazonia, with three population clusters within Brazil and one including the Peru populations. The considerable differences in Ne among the populations may have contributed to the observed genetic differentiation. All of the data suggest that the primary division within A. darlingi corresponds to two white gene genotypes between Amazonia (genotype 1

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

    Science.gov (United States)

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

    2013-05-01

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

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

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    Renata S. Leão

    2013-05-01

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

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

    Science.gov (United States)

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

    2017-12-01

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

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

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    A. J. Dolman

    1999-08-01

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

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

    Science.gov (United States)

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

    This chapter constitutes an updated review of long-term climate variability and change in the Amazon region, based on observational data spanning more than 50 years of records and on climate-change modeling studies. We start with the early experiments on Amazon deforestation in the late 1970s, and the evolution of these experiments to the latest studies on greenhouse gases emission scenarios and land use changes until the end of the twenty-first century. The "Amazon dieback" simulated by the HadCM3 model occurs after a "tipping point" of CO2 concentration and warming. Experiments on Amazon deforestation and change of climate suggest that once a critical deforestation threshold (or tipping point) of 40-50% forest loss is reached in eastern Amazonia, climate would change in a way which is dangerous for the remaining forest. This may favor a collapse of the tropical forest, with a substitution of the forest by savanna-type vegetation. The concept of "dangerous climate change," as a climate change, which induces positive feedback, which accelerate the change, is strongly linked to the occurrence of tipping points, and it can be explained as the presence of feedback between climate change and the carbon cycle, particularly involving a weakening of the current terrestrial carbon sink and a possible reversal from a sink (as in present climate) to a source by the year 2050. We must, therefore, currently consider the drying simulated by the Hadley Centre model(s) as having a finite probability under global warming, with a potentially enormous impact, but with some degree of uncertainty.

  11. Increased Wildfire Risk Driven by Climate and Development Interactions in the Bolivian Chiquitania, Southern Amazonia.

    Science.gov (United States)

    Devisscher, Tahia; Anderson, Liana O; Aragão, Luiz E O C; Galván, Luis; Malhi, Yadvinder

    2016-01-01

    Wildfires are becoming increasingly dominant in tropical landscapes due to reinforcing feedbacks between land cover change and more severe dry conditions. This study focused on the Bolivian Chiquitania, a region located at the southern edge of Amazonia. The extensive, unique and well-conserved tropical dry forest in this region is susceptible to wildfires due to a marked seasonality. We used a novel approach to assess fire risk at the regional level driven by different development trajectories interacting with changing climatic conditions. Possible future risk scenarios were simulated using maximum entropy modelling with presence-only data, combining land cover, anthropogenic and climatic variables. We found that important determinants of fire risk in the region are distance to roads, recent deforestation and density of human settlements. Severely dry conditions alone increased the area of high fire risk by 69%, affecting all categories of land use and land cover. Interactions between extreme dry conditions and rapid frontier expansion further increased fire risk, resulting in potential biomass loss of 2.44±0.8 Tg in high risk area, about 1.8 times higher than the estimates for the 2010 drought. These interactions showed particularly high fire risk in land used for 'extensive cattle ranching', 'agro-silvopastoral use' and 'intensive cattle ranching and agriculture'. These findings have serious implications for subsistence activities and the economy in the Chiquitania, which greatly depend on the forestry, agriculture and livestock sectors. Results are particularly concerning if considering the current development policies promoting frontier expansion. Departmental protected areas inhibited wildfires when strategically established in areas of high risk, even under drought conditions. However, further research is needed to assess their effectiveness accounting for more specific contextual factors. This novel and simple modelling approach can inform fire and land

  12. Increased Wildfire Risk Driven by Climate and Development Interactions in the Bolivian Chiquitania, Southern Amazonia.

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    Tahia Devisscher

    Full Text Available Wildfires are becoming increasingly dominant in tropical landscapes due to reinforcing feedbacks between land cover change and more severe dry conditions. This study focused on the Bolivian Chiquitania, a region located at the southern edge of Amazonia. The extensive, unique and well-conserved tropical dry forest in this region is susceptible to wildfires due to a marked seasonality. We used a novel approach to assess fire risk at the regional level driven by different development trajectories interacting with changing climatic conditions. Possible future risk scenarios were simulated using maximum entropy modelling with presence-only data, combining land cover, anthropogenic and climatic variables. We found that important determinants of fire risk in the region are distance to roads, recent deforestation and density of human settlements. Severely dry conditions alone increased the area of high fire risk by 69%, affecting all categories of land use and land cover. Interactions between extreme dry conditions and rapid frontier expansion further increased fire risk, resulting in potential biomass loss of 2.44±0.8 Tg in high risk area, about 1.8 times higher than the estimates for the 2010 drought. These interactions showed particularly high fire risk in land used for 'extensive cattle ranching', 'agro-silvopastoral use' and 'intensive cattle ranching and agriculture'. These findings have serious implications for subsistence activities and the economy in the Chiquitania, which greatly depend on the forestry, agriculture and livestock sectors. Results are particularly concerning if considering the current development policies promoting frontier expansion. Departmental protected areas inhibited wildfires when strategically established in areas of high risk, even under drought conditions. However, further research is needed to assess their effectiveness accounting for more specific contextual factors. This novel and simple modelling approach can

  13. The costs of evaluating species densities and composition of snakes to assess development impacts in amazonia.

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    Rafael de Fraga

    Full Text Available Studies leading to decision-making for environmental licensing often fail to provide accurate estimates of diversity. Measures of snake diversity are regularly obtained to assess development impacts in the rainforests of the Amazon Basin, but this taxonomic group may be subject to poor detection probabilities. Recently, the Brazilian government tried to standardize sampling designs by the implementation of a system (RAPELD to quantify biological diversity using spatially-standardized sampling units. Consistency in sampling design allows the detection probabilities to be compared among taxa, and sampling effort and associated cost to be evaluated. The cost effectiveness of detecting snakes has received no attention in Amazonia. Here we tested the effects of reducing sampling effort on estimates of species densities and assemblage composition. We identified snakes in seven plot systems, each standardised with 14 plots. The 250 m long centre line of each plot followed an altitudinal contour. Surveys were repeated four times in each plot and detection probabilities were estimated for the 41 species encountered. Reducing the number of observations, or the size of the sampling modules, caused significant loss of information on species densities and local patterns of variation in assemblage composition. We estimated the cost to find a snake as $ 120 U.S., but general linear models indicated the possibility of identifying differences in assemblage composition for half the overall survey costs. Decisions to reduce sampling effort depend on the importance of lost information to target-issues, and may not be the preferred option if there is the potential for identifying individual snake species requiring specific conservation actions. However, in most studies of human disturbance on species assemblages, it is likely to be more cost-effective to focus on other groups of organisms with higher detection probabilities.

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

    Directory of Open Access Journals (Sweden)

    A. J. Dolman

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

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

  15. Las palmas entre los grupos cazadores-recolectores de la Amazonia Colombiana

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    Morcote Ríos Gaspar

    1998-06-01

    Full Text Available We compare past and present systems of management of palms in the Colombian Amazon, based on archaeological studies of preceramic groups in the middle Caquetá region and ethnographic research on the nomadic Nukak people, who inhabit northeastern Guaviare department. Astrocaryum aculeatum, Attalea maripe, Mauritia flexuosa, Oenocarpus bataua, Oenocarpus bacaba y Oenocarpus mapora, have been used from the early Holocene through the present time. Among these, Oenocarpus bataua has remained the most important food species. We conclude that one of the mananging strategies of the tropical rain forest is the simultaneous improvement of ecological units, especially in the tertiary sedimentary plains, and that such management probably has a long history in the region.Se presenta una comparación sobre el manejo de las palmas en la Amazonia Colombiana, basado en los resultados de un estudio arqueológico de grupos precerámicos en la región del Medio Caquetá y uno etnográfico del pueblo nómada Nukak que habita la zona nororiental del departamento del Guaviare. Se encontró que Astrocaryum aculeatum, A ttalea maripa, Mauritia flexuosa, Oenocarpus bataua, Oenocarpus bacaba y Oenocarpus mapora son algunas de las palmas usadas desde el Holoceno temprano hasta el presente. Entre estas Oenocarpus bataua es la especie más importante como fuente de alimento. Así mismo, se concluye que una de las estrategias de manejo en el bosque húmedo tropical es el aprovechamiento simultáneo de diferentes unidades ecológicas, con predominio del plano sedimentario terciario. Es probable que este tipo de manejo tenga en la región una larga historia.

  16. A 6900-year history of landscape modification by humans in lowland Amazonia

    Science.gov (United States)

    Bush, M. B.; Correa-Metrio, A.; McMichael, C. H.; Sully, S.; Shadik, C. R.; Valencia, B. G.; Guilderson, T.; Steinitz-Kannan, M.; Overpeck, J. T.

    2016-06-01

    A sedimentary record from the Peruvian Amazon provided evidence of climate and vegetation change for the last 6900 years. Piston cores collected from the center of Lake Sauce, a 20 m deep lake at 600 m elevation, were 19.7 m in length. The fossil pollen record showed a continuously forested catchment within the period of the record, although substantial changes in forest composition were apparent. Fossil charcoal, found throughout the record, was probably associated with humans setting fires. Two fires, at c. 6700 cal BP and 4270 cal BP, appear to have been stand-replacing events possibly associated with megadroughts. The fire event at 4270 cal BP followed a drought that caused lowered lake levels for several centuries. The successional trajectories of forest recovery following these large fires were prolonged by smaller fire events. Fossil pollen of Zea mays (cultivated maize) provided evidence of agricultural activity at the site since c. 6320 cal BP. About 5150 years ago, the lake deepened and started to deposit laminated sediments. Maize agriculture reached a peak of intensity between c. 3380 and 700 cal BP. Fossil diatom data provided a proxy for lake nutrient status and productivity, both of which peaked during the period of maize cultivation. A marked change in land use was evident after c. 700 cal BP when maize agriculture was apparently abandoned at this site. Iriartea, a hyperdominant of riparian settings in western Amazonia, increased in abundance within the last 1100 years, but declined markedly at c. 1070 cal BP and again between c. 80 and -10 cal BP.

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

    NARCIS (Netherlands)

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

    2006-01-01

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

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

    Science.gov (United States)

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

    2015-01-01

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

  19. Co-Evolution and Bio-Social Construction: The Kichwa Agroforestry Systems (Chakras in the Ecuadorian Amazonia

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    Daniel Coq-Huelva

    2017-10-01

    Full Text Available Polycultured agrarian systems in Ecuadorian Amazonia (also called chakras or swollen gardens are characterised by a market-oriented crop for the generation of monetary income, for example, cocoa, other agricultural products (e.g., banana and cassava, and livestock for family farm consumption. Moreover, a chakra is an outstanding example of agroforestry production, in which ecological, social and economic elements co-evolve from a set of close and strong connections. In this context, the conservation and transformation of their biological subsystems can be understood as the result of complex interactions between anthropogenic and non-anthropogenic factors. In turn, such interactions are essential to provide food and monetary income to the indigenous community. Relevant agency capabilities exist that could cause an agroforestry system to take a different path of co-evolution, that is, towards greater or lesser sustainability associated with different levels of complexity. In conclusion, chakras have key ecological features that can mitigate the impact of human population growth in Amazonia. Additionally, chakras have their own processes of social self-regulation which enhance the possibilities of adaptation of Kichwa communities to changing environmental conditions, being essential elements in local food sovereignty, equitable gender relations and the respect of ancestral wisdom.

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

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    Ruiz-Peinado Alonso, José Luis

    2010-08-01

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

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

  1. Fauna de coleópteros aquáticos (insect: coleoptera na Amazônia central, Brasil Aquatic Beetlefauna (insecta: coleoptera in Central Amazonia, Brazil

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    Cesar João Benetti

    2003-12-01

    Full Text Available Foram coletados 888 exemplares de Coleoptera aquáticos nos municípios de Manaus, Manacapuru e Presidente Figueiredo (AM, de fevereiro de 2000 a agosto de 2002, distribuídos em 12 famílias, 50 gêneros e 88 espécies ou morfoespécies. Novas ocorrências para o Brasil, incluem as seguintes espécies de Dytiscidae: Hydrodessus robinae, H. surinamensis, Hypodessus frustrator, Neobidessus confusus, N. spangleri e N. woodruffi. Os gêneros Agaporomorphus (Dytiscidae e Pronoterus (Noteridae são registrados pela primeira vez para o estado do Amazonas, assim como as espécies: P. punctipennis e Suphisellus nigrinus (Noteridae; Agaporomorphus grandisinuatus, Bidessonotus tibialis, Derovatellus lentus,Desmopachria nitida, Hydaticus xanthomelas, Laccophilus tarsalis, Liodessus affinis e Megadytes laevigatus (Dytiscidae. A família Dytiscidae foi a que apresentou maior riqueza, com 34 espécies, seguida de Hydrophilidae, com 20 e Noteridae, com 12 espécies. Os gêneros com maior número de espécies foram Gyretes (Gyrinidae e Suphisellus (Noteridae com 6 espécies, Copelatus (Dytiscidae e Tropisternus (Hydrophilidae, com 5 espécies.In this work, 888 specimens of aquatic Coleoptera were collected in Manaus, Manacapuru and Presidente Figueiredo counties (AM, distributed in 12 families, 50 genera and 88 species or morphospecies. New occurrences in Brasil include the following species of Dytiscidae: Hydrodessus robinae, H. surinamensis, Hypodessus frustrator, Neobidessus confusus, N. spangleri and N. woodruffi. The genera Agaporomorphus (Dytiscidae and Pronoterus (Noteridae were reported for the first time in the State of Amazonas, as well as the species P. punctipennis and Suphisellus nigrinus (Noteridae; Agaporomorphus grandisinuatus, Bidessonotus tibialis, Derovatellus lentus,Desmopachria nitida, Hydaticus xanthomelas, Laccophilus tarsalis, Liodessus affinis and Megadytes laevigatus (Dytiscidae. The family Dytiscidae presented the highest richness, with 34 species, followed by Hydrophilidae, with 20 and Noteridae, with 12 espécies. The genera with greatest number of species were Gyretes (Gyrinidae and Suphisellus (Noteridae with 6 species, Copelatus (Dytiscidae and Tropisternus (Hydrophilidae with 5 species.

  2. Size distribution and hygroscopic properties of aerosol particles from dry-season biomass burning in Amazonia

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    J. Rissler

    2006-01-01

    Full Text Available Aerosol particle number size distributions and hygroscopic properties were measured at a pasture site in the southwestern Amazon region (Rondonia. The measurements were performed 11 September-14 November 2002 as part of LBA-SMOCC (Large scale Biosphere atmosphere experiment in Amazonia - SMOke aerosols, Clouds, rainfall and Climate, and cover the later part of the dry season (with heavy biomass burning, a transition period, and the onset of the wet period. Particle number size distributions were measured with a DMPS (Differential Mobility Particle Sizer, 3-850nm and an APS (Aerodynamic Particle Sizer, extending the distributions up to 3.3 µm in diameter. An H-TDMA (Hygroscopic Tandem Differential Mobility Analyzer measured the hygroscopic diameter growth factors (Gf at 90% relative humidity (RH, for particles with dry diameters (dp between 20-440 nm, and at several occasions RH scans (30-90% RH were performed for 165nm particles. These data provide the most extensive characterization of Amazonian biomass burning aerosol, with respect to particle number size distributions and hygroscopic properties, presented until now. The evolution of the convective boundary layer over the course of the day causes a distinct diel variation in the aerosol physical properties, which was used to get information about the properties of the aerosol at higher altitudes. The number size distributions averaged over the three defined time periods showed three modes; a nucleation mode with geometrical median diameters (GMD of ~12 nm, an Aitken mode (GMD=61-92 nm and an accumulation mode (GMD=128-190 nm. The two larger modes were shifted towards larger GMD with increasing influence from biomass burning. The hygroscopic growth at 90% RH revealed a somewhat external mixture with two groups of particles; here denoted nearly hydrophobic (Gf~1.09 for 100 nm particles and moderately hygroscopic (Gf~1.26. While the hygroscopic growth factors were surprisingly similar over the

  3. Hair mercury (signature of fish consumption) and cardiovascular risk in Munduruku and Kayabi Indians of Amazonia.

    Science.gov (United States)

    Dórea, José G; de Souza, Jurandir R; Rodrigues, Patricia; Ferrari, Iris; Barbosa, Antonio C

    2005-02-01

    Fish is an important natural resource in the diet of inhabitants of the Amazon rain forest and a marker of its consumption (hair Hg) was used to compare selected cardiovascular risk parameters between tribes of Eastern Amazonia. Three Munduruku (Terra Preta, Kaburua, Cururu) villages and one Kayabi village at the banks of head rivers (Tapajos, Tropas, Kabitutu, Cururu, Curuzinho, Teles Pires) of the Tapajos Basin were studied in relation to fish Hg concentrations, mercury in hair (fish consumption) and erythrocytes, body mass index (height/weight, kg/cm2), and blood pressure. The mean fish Hg concentrations were higher in predatory (578.6 ng/g) than in nonpredatory species (52.8 ng/g). Overall only 26% of fish Hg concentrations were above 500 ng/g, and only 11% were above 1000 ng/g. There was no systematic trend in fish Hg concentrations from rivers with a history of gold-mining activities. The biomarker of fish consumption (hair Hg) was significantly associated with erythrocyte-Hg (r=0.5181; P=0.0001) and was significantly higher in Kayabi (12.7 microg/g) than in the Munduruku (3.4 microg/g). Biomarker-assessed fish consumption rate was higher in the Kayabi (110 g/day) than in the Munduruku villages (30 g/day). Although no significant differences in body mass index (BMI) were observed between tribes, there was a trend of lower increase in blood pressure with age among the higher fish consumers (Kayabi). Summary clinical evaluation did not detect neurologic complaints compatible with Hg intoxication (paraparesis, numbness, tremor, balancing failure), but endemic tropical diseases such as clinical history of malaria showed a high prevalence (55.4%). Fish is an abundant natural resource, important in the Indian diet, that has been historically consumed without perceived problems and can easily be traced through hair Hg. The exposure to freshwater fish monomethyl mercury is less of an issue than endemic infectious diseases such as malaria and lack of basic medical

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

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    Philip M. Fearnside

    2008-06-01

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

  5. Trabajo y relaciones laborales en los enclaves minero-metalúrgicos de la Amazonia

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    Josep Pont Vidal

    2008-04-01

    Full Text Available Abstract:  Labour and labour relations in the enclaves of metallurgical mining in the AmazonThis article is based upon an empirical study of  life and labour conditions in the metallurgical  mining enclaves of the eastern Amazon region.  From the perspective of civil society (associations  of workers, labour conditions are analysed according to interviews with workers and their  family members given outside the work sphere.  Using the method based on ‘grounded theory’, and specifically on the qualitative analysis of  theorization, a scheme of two levels has been  made: the ‘situational activity’ and the ‘subjectivization of the activity’. The first level, the ‘situational activity’, is centred in the sphere of the  organizations of workers and their perceptions  and strategies for action. The second level, the  ‘subjective of the activity’, addresses the subjective interpretations adopted by workers and their  families. Resumen:Este escrito se basa en un estudio empírico de las  condiciones de vida y relaciones laborales en los  enclaves minero-metalúrgicos de la Amazonia  oriental. En él se analizan las condiciones laborales desde la perspectiva de la sociedad civil (asociaciones de trabajadores, recurriendo para ello a  entrevistas con trabajadores y sus familias fuera  del ambiente de trabajo. A partir del método basado en la teorización anclada, y específicamente  en el denominado análisis cualitativo de teorización, se ha confeccionado un esquema de dos  niveles: la ‘actividad situacional’, y la ‘subjetivización de la actividad’. El primer nivel -la ‘actividad situacional’- se centra en la esfera de las  organizaciones de trabajadores y sus ideas y estrategias de acción. El segundo nivel -la ‘subjetivización de la actividad’- trata las interpretaciones  subjetivas adoptadas por los trabajadores y sus  familias.

  6. [Distribution patterns of canopy and understory tree species at local scale in a Tierra Firme forest, the Colombian Amazonia].

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    Barreto-Silva, Juan Sebastian; López, Dairon Cárdenas; Montoya, Alvaro Javier Duque

    2014-03-01

    The effect of environmental variation on the structure of tree communities in tropical forests is still under debate. There is evidence that in landscapes like Tierra Firme forest, where the environmental gradient decreases at a local level, the effect of soil on the distribution patterns of plant species is minimal, happens to be random or is due to biological processes. In contrast, in studies with different kinds of plants from tropical forests, a greater effect on floristic composition of varying soil and topography has been reported. To assess this, the current study was carried out in a permanent plot of ten hectares in the Amacayacu National Park, Colombian Amazonia. To run the analysis, floristic and environmental variations were obtained according to tree species abundance categories and growth forms. In order to quantify the role played by both environmental filtering and dispersal limitation, the variation of the spatial configuration was included. We used Detrended Correspondence Analysis and Canonical Correspondence Analysis, followed by a variation partitioning, to analyze the species distribution patterns. The spatial template was evaluated using the Principal Coordinates of Neighbor Matrix method. We recorded 14 074 individuals from 1 053 species and 80 families. The most abundant families were Myristicaceae, Moraceae, Meliaceae, Arecaceae and Lecythidaceae, coinciding with other studies from Northwest Amazonia. Beta diversity was relatively low within the plot. Soils were very poor, had high aluminum concentration and were predominantly clayey. The floristic differences explained along the ten hectares plot were mainly associated to biological processes, such as dispersal limitation. The largest proportion of community variation in our dataset was unexplained by either environmental or spatial data. In conclusion, these results support random processes as the major drivers of the spatial variation of tree species at a local scale on Tierra Firme

  7. Biodiversidad en espacios productivos y los aspectos sociales de las comunidades ribereñas de la Amazonia Occidental

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    Williane Maria de Oliveira Martins

    2014-03-01

    Full Text Available Los sistemas agrícolas ribereño representan una alternativa de producción sustentable para las comunidades tradicionales de la Amazonia, especialmente en cuanto a la diversidad de productos y la generación de ingresos. Por lo tanto, teniendo en cuenta las funciones ecológicas y sociales el propósito de este estudio fue analizar las áreas productivas y aspectos etnosociais de las comunidades ribereñas de la lejano Amazonia Occidental, Acre, Brasil. La recolección de datos se realizó a través de entrevistas participativas, formales e inductivo después de un cuestionario semi-estructurado. Toda la información recogida se transfiere a una base de datos electrónica, que sistematizado y procesado. Los sistemas agrícolas en estas comunidades son los cultivos y quintales. Los cultivos tienen una especie agrodiversidad en la misma zona, el producto principal es el cultivo de la yuca. Los quintales tienen arreglos espaciales de especies frutales, medicinales y sobre todo los cultivos de hortalizas. Así, tanto los astilleros como los claros son responsables de la sostenibilidad de las familias ribereñas de esta comunidad, sirviendo de subsistencia y asistencia económica.Por otra parte, se trata de ser una alternativa adaptada a las condiciones de los ecosistemas agrícolas llanura de inundación en la región.

  8. Vegetation and hydrology changes in Eastern Amazonia inferred from a pollen record

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    Mauro B. de Toledo

    2008-03-01

    Full Text Available Pollen, charcoal, and C14 analyses were performed on a sediment core obtained from Lake Tapera (Amapá to provide the palaeoenvironmental history of this part of Amazonia. A multivariate analysis technique, Detrended Correspondence Analysis, was applied to the pollen data to improve visualization of sample distribution and similarity. A sedimentary hiatus lasting 5,500 years was identified in the Lake Tapera. Because the timing of the hiatus overlapped with the highest Holocene sea-level, which would have increased the local water table preventing the lake from drying out, it is clear that sea-level was not important in maintaining the lake level. Lake Tapera probably depended on riverine flood waters, and the sedimentary gap was caused by reduced Amazon River discharge, due to an extremely dry period in the Andes (8,000-5,000 years BP, when precipitation levels markedly decreased. The lack of Andean pollen (river transported in the record after this event supports this interpretation. The pollen analysis shows that when sedimentation resumed in 1,620 cal. years BP, the vegetation around the lake was changed from forest into savanna. This record demonstrates the need to improve our understanding of climate changes and their associated impacts on vegetation dynamics.Análises de pólen, carvões e datações C foram conduzidas em um testemunho coletado no lago Tapera (Amapá com o objetivo de interpretar a história paleoambiental desta parte da Amazônia. Uma das técnicas de análises multivariadas, Análise de Correspondência Destendenciada (DCA, foi utilizada a fim de melhor visualizar a distribuição e similaridade das amostras. Foi identificado um hiato sedimentar com duração de 5.500 anos no lago Tapera. Como o hiato ocorreu simultaneamente ao nível do mar mais alto do Holoceno, o que deveria ter aumentado o lençol freático, impedindo assim o lago de secar, é evidente que variações do nível do mar não foram importantes na

  9. First typology of cacao (Theobroma cacao L.) systems in Colombian Amazonia, based on tree species richness, canopy structure and light availability.

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    Suárez Salazar, Juan Carlos; Ngo Bieng, Marie Ange; Melgarejo, Luz Marina; Di Rienzo, Julio A; Casanoves, Fernando

    2018-01-01

    We present a typology of cacao agroforest systems in Colombian Amazonia. These systems had yet to be described in the literature, especially their potential in terms of biodiversity conservation. The systems studied are located in a post-conflict area, and a deforestation front in Colombian Amazonia. Cacao cropping systems are of key importance in Colombia: cacao plays a prime role in post conflict resolution, as cacao is a legal crop to replace illegal crops; cacao agroforests are expected to be a sustainable practice, promoting forest-friendly land use. We worked in 50 x 2000 m2 agroforest plots, in Colombian Amazonia. A cluster analysis was used to build a typology based on 28 variables characterised in each plot, and related to diversity, composition, spatial structure and light availability for the cacao trees. We included variables related to light availability to evaluate the amount of transmitted radiation to the cacao trees in each type, and its suitability for cacao ecophysiological development. We identified 4 types of cacao agroforests based on differences concerning tree species diversity and the impact of canopy spatial structure on light availability for the cacao trees in the understorey. We found 127 tree species in the dataset, with some exclusive species in each type. We also found that 3 out of the 4 types identified displayed an erosion of tree species diversity. This reduction in shade tree species may have been linked to the desire to reduce shade, but we also found that all the types described were compatible with good ecophysiological development of the cacao trees. Cacao agroforest systems may actually be achieving biodiversity conservation goals in Colombian Amazonia. One challenging prospect will be to monitor and encourage the conservation of tree species diversity in cacao agroforest systems during the development of these cropping systems, as a form of forest-friendly management enhancing sustainable peace building in Colombia.

  10. First typology of cacao (Theobroma cacao L.) systems in Colombian Amazonia, based on tree species richness, canopy structure and light availability

    Science.gov (United States)

    Suárez Salazar, Juan Carlos; Melgarejo, Luz Marina; Di Rienzo, Julio A.; Casanoves, Fernando

    2018-01-01

    Aim and background We present a typology of cacao agroforest systems in Colombian Amazonia. These systems had yet to be described in the literature, especially their potential in terms of biodiversity conservation. The systems studied are located in a post-conflict area, and a deforestation front in Colombian Amazonia. Cacao cropping systems are of key importance in Colombia: cacao plays a prime role in post conflict resolution, as cacao is a legal crop to replace illegal crops; cacao agroforests are expected to be a sustainable practice, promoting forest-friendly land use. Material and methods We worked in 50 x 2000 m2 agroforest plots, in Colombian Amazonia. A cluster analysis was used to build a typology based on 28 variables characterised in each plot, and related to diversity, composition, spatial structure and light availability for the cacao trees. We included variables related to light availability to evaluate the amount of transmitted radiation to the cacao trees in each type, and its suitability for cacao ecophysiological development. Main results We identified 4 types of cacao agroforests based on differences concerning tree species diversity and the impact of canopy spatial structure on light availability for the cacao trees in the understorey. We found 127 tree species in the dataset, with some exclusive species in each type. We also found that 3 out of the 4 types identified displayed an erosion of tree species diversity. This reduction in shade tree species may have been linked to the desire to reduce shade, but we also found that all the types described were compatible with good ecophysiological development of the cacao trees. Main conclusions and prospects Cacao agroforest systems may actually be achieving biodiversity conservation goals in Colombian Amazonia. One challenging prospect will be to monitor and encourage the conservation of tree species diversity in cacao agroforest systems during the development of these cropping systems, as a form of

  11. First typology of cacao (Theobroma cacao L. systems in Colombian Amazonia, based on tree species richness, canopy structure and light availability.

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    Juan Carlos Suárez Salazar

    Full Text Available We present a typology of cacao agroforest systems in Colombian Amazonia. These systems had yet to be described in the literature, especially their potential in terms of biodiversity conservation. The systems studied are located in a post-conflict area, and a deforestation front in Colombian Amazonia. Cacao cropping systems are of key importance in Colombia: cacao plays a prime role in post conflict resolution, as cacao is a legal crop to replace illegal crops; cacao agroforests are expected to be a sustainable practice, promoting forest-friendly land use.We worked in 50 x 2000 m2 agroforest plots, in Colombian Amazonia. A cluster analysis was used to build a typology based on 28 variables characterised in each plot, and related to diversity, composition, spatial structure and light availability for the cacao trees. We included variables related to light availability to evaluate the amount of transmitted radiation to the cacao trees in each type, and its suitability for cacao ecophysiological development.We identified 4 types of cacao agroforests based on differences concerning tree species diversity and the impact of canopy spatial structure on light availability for the cacao trees in the understorey. We found 127 tree species in the dataset, with some exclusive species in each type. We also found that 3 out of the 4 types identified displayed an erosion of tree species diversity. This reduction in shade tree species may have been linked to the desire to reduce shade, but we also found that all the types described were compatible with good ecophysiological development of the cacao trees.Cacao agroforest systems may actually be achieving biodiversity conservation goals in Colombian Amazonia. One challenging prospect will be to monitor and encourage the conservation of tree species diversity in cacao agroforest systems during the development of these cropping systems, as a form of forest-friendly management enhancing sustainable peace building in

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

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    Tiago Magalhães da Silva Freitas

    2011-01-01

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

  13. Neotropics provide insights into the emergence of New World monkeys: New dental evidence from the late Oligocene of Peruvian Amazonia.

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    Marivaux, Laurent; Adnet, Sylvain; Altamirano-Sierra, Ali J; Boivin, Myriam; Pujos, François; Ramdarshan, Anusha; Salas-Gismondi, Rodolfo; Tejada-Lara, Julia V; Antoine, Pierre-Olivier

    2016-08-01

    Recent field efforts in Peruvian Amazonia (Contamana area, Loreto Department) have resulted in the discovery of a late Oligocene (ca. 26.5 Ma; Chambira Formation) fossil primate-bearing locality (CTA-61). In this paper, we analyze the primate material consisting of two isolated upper molars, the peculiar morphology of which allows us to describe a new medium-sized platyrrhine monkey: Canaanimico amazonensis gen. et sp. nov. In addition to the recent discovery of Perupithecus ucayaliensis, a primitive anthropoid taxon of African affinities from the alleged latest Eocene Santa Rosa locality (Peruvian Amazonia), the discovery of Canaanimico adds to the evidence that primates were well-established in the Amazonian Basin during the Paleogene. Our phylogenetic results based on dental evidence show that none of the early Miocene Patagonian taxa (Homunculus, Carlocebus, Soriacebus, Mazzonicebus, Dolichocebus, Tremacebus, and Chilecebus), the late Oligocene Bolivian Branisella, or the Peruvian Canaanimico, is nested within a crown platyrrhine clade. All these early taxa are closely related and considered here as stem Platyrrhini. Canaanimico is nested within the Patagonian Soriacebinae, and closely related to Soriacebus, thereby extending back the soriacebine lineage to 26.5 Ma. Given the limited dental evidence, it is difficult to assess if Canaanimico was engaged in a form of pitheciine-like seed predation as is observed in Soriacebus and Mazzonicebus, but dental microwear patterns recorded on one upper molar indicate that Canaanimico was possibly a fruit and hard-object eater. If Panamacebus, a recently discovered stem cebine from the early Miocene of Panama, indicates that the crown platyrrhine radiation was already well underway by the earliest Miocene, Canaanimico indicates in turn that the "homunculid" radiation (as a part of the stem radiation) was well underway by the late Oligocene. These new data suggest that the stem radiation likely occurred in the Neotropics

  14. CRECIMIENTO DEL MAÍZ EN VERTISOLES CON ALTO ALUMINIO EN LA BAIXADA MARANHENSE PRE-AMAZONIA, BRASIL

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    Alessandro Costa da Silva

    2014-01-01

    Full Text Available Crecimiento del maíz en vertisoles con alto aluminio en la Baixada Maranhense pre-Amazonia, Brasil. El objetivo de este trabajo fue evaluar el crecimiento del maíz en suelos con alto contenido de aluminio. Se midió el efecto del Al3+ en raíces y la cantidad de materia seca (raíz, hoja y tallo de maíz. Se efectuó la caracterización físico-química de cuatro muestras de suelo con alto aluminio colectadas del horizonte Ap, en tres municipios de la región conocida como Baixada Maranhense (Pre-Amazonia, Brasil: Santa Rita (SR, Arari (AR y Vitoria do Mearim (VM y un testigo colectado en el municipio de São Luís, Área del Núcleo de Tecnología Rural (T. El estudio, ejecutado en 2009, se llevó a cabo en invernadero y se utilizó 2 dm3 de suelo por maceta. Asimismo las muestras fueron divididas en muestras con y sin fertilización. La variación en la longitud de la raíz y de materia seca de las hojas difirió significativamente entre tratados con y sin fertilizante, excepto en la muestra de la localidad T. La producción de materia seca de raíz, tallo y hoja fue mayor en todos los suelos cuando se fertilizó. El suelo testigo también superó a todos los demás en cuanto a producción de materia seca en la raíz, posiblemente como resultado de una menor cantidad de Al3+ (1,2 cmolc/dm3 en comparación con los suelos SR, AR y VM (6,8; 8,0 y 7,0 cmolc/dm3 respectivamente. Se concluye la fertilización reduce el efecto detrimental del aluminio en la producción de maíz en la Baixada Maranhense.

  15. Farmers’ Perceptions on the Agricultural use of Human Urine in the Central Amazon

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    Patrícia Müller

    2017-01-01

    Full Text Available The Urine Diverting Dry Toilet (UDDT provides a technological alternative for the challenging environments found in Amazonia, and has the advantage of not consuming water. To verify its viability, however, it is necessary to understand user behavior in relation to the use of the toilet’s byproducts. The objective of the present study was to evaluate farmer’s perceptions of the use of human urine as a fertilizer for agricultural crops in the Central Amazon. We interviewed 73 smallholder farmers from a rural village in Tefé County and in the municipal farmers market of Tefé. It was verified that 12% of farmers have knowledge of the use of human urine in agriculture, and that more than a third consider it possible to use urine in their gardens and fields. However, more than half did not consider the possibility of using urine, manifesting concerns about crop development and doubts regarding the efficacy of its use as a fertilizer. The informants believed that crops watered with urine would be adequate for human consumption. It is possible to conclude that human urine has the potential to be used in agriculture in the study region and we understand that dry toilets should not be taken as the only alternative for sanitation in Amazonia.

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

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

    2017-11-01

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

  17. Alluvial plain dynamics and human occupation in SW Amazonia during the Holocene: A paleosol-based reconstruction

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    Lombardo, Umberto; Rodrigues, Leonor; Veit, Heinz

    2018-01-01

    The present study reconstructs Holocene fluvial dynamics in the southern Amazonian foreland basin through the analysis of 36 stratigraphic profiles taken along a 300 km long transect across the Llanos de Moxos (LM), in the Bolivian Amazon. Based on 50 radiocarbon ages from paleosols intercalated with fluvial sediments, the most important changes in floodplain dynamics on a millennial scale are reconstructed and the links between pre-Columbian cultural processes and environmental change in the region explored. Results show that the frequency of river avulsions and crevasses, as inferred from the number and age of the cored paleosols, is stable from 8k cal. yrs BP to 4k cal. yrs BP and increases significantly from 4k to 2k cal. yrs BP, following the strengthening of el Niño/la Niña cycle and an increase in average precipitation. Fluvial activity then decreases and reaches its minimum after 2k cal BP. A comparison between the stratigraphic record and the archaeological record shows a match between periods of landscape stability in SW Amazonia (low river activity) and periods of pre-Columbian human occupation. The first Amazonians lived in the LM until 4k yrs. BP, when an abrupt increase in the frequency of river avulsions and crevasses forced the abandonment of the region. After two thousand years of archaeological hiatus, which matches the period of highest river activity in the region, agriculturists reoccupied the Bolivian Amazon.

  18. A Spatial Probit Econometric Model of Land Change: The Case of Infrastructure Development in Western Amazonia, Peru

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    Arima, E. Y.

    2016-01-01

    Tropical forests are now at the center stage of climate mitigation policies worldwide given their roles as sources of carbon emissions resulting from deforestation and forest degradation. Although the international community has created mechanisms such as REDD+ to reduce those emissions, developing tropical countries continue to invest in infrastructure development in an effort to spur economic growth. Construction of roads in particular is known to be an important driver of deforestation. This article simulates the impact of road construction on deforestation in Western Amazonia, Peru, and quantifies the amount of carbon emissions associated with projected deforestation. To accomplish this objective, the article adopts a Bayesian probit land change model in which spatial dependencies are defined between regions or groups of pixels instead of between individual pixels, thereby reducing computational requirements. It also compares and contrasts the patterns of deforestation predicted by both spatial and non-spatial probit models. The spatial model replicates complex patterns of deforestation whereas the non-spatial model fails to do so. In terms of policy, both models suggest that road construction will increase deforestation by a modest amount, between 200–300 km2. This translates into aboveground carbon emissions of 1.36 and 1.85 x 106 tons. However, recent introduction of palm oil in the region serves as a cautionary example that the models may be underestimating the impact of roads. PMID:27010739

  19. Diversity and abundance of primates and their threats in the interfluvium of the Napo and Putumayo rivers, Peruvian Amazonia

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    Rolando Aquino

    2016-12-01

    Full Text Available Within the northeastern Peruvian Amazonia remain areas with scarce information on primates, one of them being the interfluvium between the Napo and Putumayo rivers. This lack of information motivated us to conduct a study to determine the diversity and abundance of primates within the area, as well as to identify the threats, which inhibit these primate species populations. For this purpose, we conducted transect censuses in three sampling sites in October 2007, September 2013 and November 2014. In 1040 km of transect walks we observed 308 groups of nine primate species, the most common being Leontocebus nigricollis (109 groups and the rarest being Alouatta seniculus (16 groups. Smaller groups of Lagothrix lagothricha lagothricha (8-11 individuals and A. seniculus (3-5 individuals were observed in Tamboryacu, a majorly disturbed sampling site. Likewise, the lowest population densities estimated for L. l. lagothricha and A. seniculus corresponded to this same sampling site with 3.8 indiv. /km2 and 1.6 indiv. /km2, respectively, while for the remaining species there were no major differences among the sampling sites. Among the activities, hunting and logging are the predominant threats responsible for the scarce populations of A. seniculus and l. l. lagothricha, mainly in the Napo River Basin.

  20. A Spatial Probit Econometric Model of Land Change: The Case of Infrastructure Development in Western Amazonia, Peru.

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    E Y Arima

    Full Text Available Tropical forests are now at the center stage of climate mitigation policies worldwide given their roles as sources of carbon emissions resulting from deforestation and forest degradation. Although the international community has created mechanisms such as REDD+ to reduce those emissions, developing tropical countries continue to invest in infrastructure development in an effort to spur economic growth. Construction of roads in particular is known to be an important driver of deforestation. This article simulates the impact of road construction on deforestation in Western Amazonia, Peru, and quantifies the amount of carbon emissions associated with projected deforestation. To accomplish this objective, the article adopts a Bayesian probit land change model in which spatial dependencies are defined between regions or groups of pixels instead of between individual pixels, thereby reducing computational requirements. It also compares and contrasts the patterns of deforestation predicted by both spatial and non-spatial probit models. The spatial model replicates complex patterns of deforestation whereas the non-spatial model fails to do so. In terms of policy, both models suggest that road construction will increase deforestation by a modest amount, between 200-300 km2. This translates into aboveground carbon emissions of 1.36 and 1.85 x 106 tons. However, recent introduction of palm oil in the region serves as a cautionary example that the models may be underestimating the impact of roads.

  1. Reproducing the organic matter model of anthropogenic dark earth of Amazonia and testing the ecotoxicity of functionalized charcoal compounds

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    Carolina Rodrigues Linhares

    2012-05-01

    Full Text Available The objective of this work was to obtain organic compounds similar to the ones found in the organic matter of anthropogenic dark earth of Amazonia (ADE using a chemical functionalization procedure on activated charcoal, as well as to determine their ecotoxicity. Based on the study of the organic matter from ADE, an organic model was proposed and an attempt to reproduce it was described. Activated charcoal was oxidized with the use of sodium hypochlorite at different concentrations. Nuclear magnetic resonance was performed to verify if the spectra of the obtained products were similar to the ones of humic acids from ADE. The similarity between spectra indicated that the obtained products were polycondensed aromatic structures with carboxyl groups: a soil amendment that can contribute to soil fertility and to its sustainable use. An ecotoxicological test with Daphnia similis was performed on the more soluble fraction (fulvic acids of the produced soil amendment. Aryl chloride was formed during the synthesis of the organic compounds from activated charcoal functionalization and partially removed through a purification process. However, it is probable that some aryl chloride remained in the final product, since the ecotoxicological test indicated that the chemical functionalized soil amendment is moderately toxic.

  2. A Spatial Probit Econometric Model of Land Change: The Case of Infrastructure Development in Western Amazonia, Peru.

    Science.gov (United States)

    Arima, E Y

    2016-01-01

    Tropical forests are now at the center stage of climate mitigation policies worldwide given their roles as sources of carbon emissions resulting from deforestation and forest degradation. Although the international community has created mechanisms such as REDD+ to reduce those emissions, developing tropical countries continue to invest in infrastructure development in an effort to spur economic growth. Construction of roads in particular is known to be an important driver of deforestation. This article simulates the impact of road construction on deforestation in Western Amazonia, Peru, and quantifies the amount of carbon emissions associated with projected deforestation. To accomplish this objective, the article adopts a Bayesian probit land change model in which spatial dependencies are defined between regions or groups of pixels instead of between individual pixels, thereby reducing computational requirements. It also compares and contrasts the patterns of deforestation predicted by both spatial and non-spatial probit models. The spatial model replicates complex patterns of deforestation whereas the non-spatial model fails to do so. In terms of policy, both models suggest that road construction will increase deforestation by a modest amount, between 200-300 km2. This translates into aboveground carbon emissions of 1.36 and 1.85 x 106 tons. However, recent introduction of palm oil in the region serves as a cautionary example that the models may be underestimating the impact of roads.

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

    Directory of Open Access Journals (Sweden)

    Almeyda Zambrano Angelica

    2010-01-01

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

  4. Climate impacts of deforestation/land-use changes in Central South America in the PRECIS regional climate model: mean precipitation and temperature response to present and future deforestation scenarios.

    Science.gov (United States)

    Canziani, Pablo O; Carbajal Benitez, Gerardo

    2012-01-01

    Deforestation/land-use changes are major drivers of regional climate change in central South America, impacting upon Amazonia and Gran Chaco ecoregions. Most experimental and modeling studies have focused on the resulting perturbations within Amazonia. Using the Regional Climate Model PRECIS, driven by ERA-40 reanalysis and ECHAM4 Baseline model for the period 1961-2000 (40-year runs), potential effects of deforestation/land-use changes in these and other neighboring ecoregions are evaluated. Current 2002 and estimated 2030 land-use scenarios are used to assess PRECIS's response during 1960-2000. ERA-40 and ECHAM4 Baseline driven runs yield similar results. Precipitation changes for 2002 and 2030 land-use scenarios, while significant within deforested areas, do not result in significant regional changes. For temperature significant changes are found within deforested areas and beyond, with major temperature enhancements during winter and spring. Given the current climate, primary effects of deforestation/land-use changes remain mostly confined to the tropical latitudes of Gran Chaco, and Amazonia.

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

    Science.gov (United States)

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

    2013-08-01

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

  6. Central Chile

    Science.gov (United States)

    2002-01-01

    The beginning of spring in central Chile looked like this to SeaWiFS. The snow-covered Andes mark the country's eastern border, and phytoplankton blooms and river sediment plumes fill the waters off its west coast. A large eddy due west of Concepcion is highlighted by the phytoplankton it contains.

  7. Afrique Centrale

    African Journals Online (AJOL)

    PR BOKO

    (Afrique Centrale) : peuplement de protozoaires ciliés et macro invertébrés ... Le lac d'Obili est un écosystème aquatique situé en plein cœur de Yaoundé en ...... électrique des eaux est assez stable, autour de 200 ; ce qui suppose que la ...

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

    Science.gov (United States)

    Nogueira, Anna Andressa Evangelista; Nogueira, Afonso César Rodrigues

    2017-12-01

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

  9. Protocol for isolation of Moniliophthora roreri (Cif and Par Evans et al. from cacao fruits cv. `National' in the Ecuadorian Amazonia

    Directory of Open Access Journals (Sweden)

    Karina Carrera-Sánchez

    2014-07-01

    Full Text Available Moniliophthora roreri is a pathogen of cocoa (Theobroma cacao L. that causes high economic losses in Ecuador. This paper is intended to present a protocol for the isolation of the pathogen from cocoa fruits cv. `National', showing signs and symptoms of disease. The fruits were collected on farms of Napo (Ecuador. By wet chamber, it was able to induce profusely, sporulation on the surface of selected lesions. The isolations were performed from conidia directly located on the surface of fruits with brown powdery appearance. Isolation procedures and suggested of possible applications are presented.   Key words: amazonia, basidiomycetes, fungi, moniliasis, Theobroma cacao L.

  10. Dental remains of cebid platyrrhines from the earliest late Miocene of Western Amazonia, Peru: Macroevolutionary implications on the extant capuchin and marmoset lineages.

    Science.gov (United States)

    Marivaux, Laurent; Adnet, Sylvain; Altamirano-Sierra, Ali J; Pujos, François; Ramdarshan, Anusha; Salas-Gismondi, Rodolfo; Tejada-Lara, Julia V; Antoine, Pierre-Olivier

    2016-11-01

    Undoubted fossil Cebidae have so far been primarily documented from the late middle Miocene of Colombia, the late Miocene of Brazilian Amazonia, the early Miocene of Peruvian Amazonia, and very recently from the earliest Miocene of Panama. The evolutionary history of cebids is far from being well-documented, with notably a complete blank in the record of callitrichine stem lineages until and after the late middle Miocene (Laventan SALMA). Further documenting their evolutionary history is therefore of primary importance. Recent field efforts in Peruvian Amazonia (Contamana area, Loreto Department) have allowed for the discovery of an early late Miocene (ca. 11 Ma; Mayoan SALMA) fossil primate-bearing locality (CTA-43; Pebas Formation). In this study, we analyze the primate material, which consists of five isolated teeth documenting two distinct Cebidae: Cebus sp., a medium-sized capuchin (Cebinae), and Cebuella sp., a tiny marmoset (Callitrichinae). Although limited, this new fossil material of platyrrhines contributes to documenting the post-Laventan evolutionary history of cebids, and besides testifies to the earliest occurrences of the modern Cebuella and Cebus/Sapajus lineages in the Neotropics. Regarding the evolutionary history of callitrichine marmosets, the discovery of an 11 Ma-old fossil representative of the modern Cebuella pushes back by at least 6 Ma the age of the Mico/Cebuella divergence currently proposed by molecular biologists (i.e., ca. 4.5 Ma). This also extends back to > 11 Ma BP the divergence between Callithrix and the common ancestor (CA) of Mico/Cebuella, as well as the divergence between the CA of marmosets and Callimico (Goeldi's callitrichine). This discovery from Peruvian Amazonia implies a deep evolutionary root of the Cebuella lineage in the northwestern part of South America (the modern western Amazon basin), slightly before the recession of the Pebas mega-wetland system (PMWS), ca. 10.5 Ma, and well-before the subsequent

  11. Estimación de la oferta de frutos en el gradiente vertical de un bosque del medio Caquetá, Amazonia colombiana

    OpenAIRE

    Nicolás Castaño Arbleda; Julio Betancur Betancur

    2004-01-01

    Durante el año 2001 se estimó la oferta de frutos en un bosque de tierra firme de la Amazonia colombiana. Se muestrearon siete parcelas de 50 x 50 m cada una (1,75 ha), en las que se censaron todos los individuos fructificados. En total se encontraron 1.154 individuos en fruto, correspondientes a 196 especies y 57 familias. En cada ciclo de muestreo  se produjeron en promedio 15.212 frutos/ha y 16,1 kg/ha de peso seco de la cosecha. Para estimar la fructificación de cada especie y familia se ...

  12. Europa central

    Directory of Open Access Journals (Sweden)

    Karel BARTOSEK

    2010-02-01

    Full Text Available La investigación francesa continúa interesándose por Europa Central. Desde luego, hay límites a este interés en el ambiente general de mi nueva patria: en la ignorancia, producto del largo desinterés de Francia por este espacio después de la Segunda Guerra Mundial, y en el comportamiento y la reflexión de la clase política y de los medios de comunicación (una anécdota para ilustrar este ambiente: durante la preparación de nuestro coloquio «Refugiados e inmigrantes de Europa Central en el movimiento antifascista y la Resistencia en Francia, 1933-1945», celebrado en París en octubre de 1986, el problema de la definición fue planteado concreta y «prácticamente». ¡Y hubo entonces un historiador eminente, para quién Alemania no formaría parte de Europa Central!.

  13. Chagas disease and globalization of the Amazon La enfermedad de Chagas y la globalización de la Amazonia

    Directory of Open Access Journals (Sweden)

    Roberto Briceño-León

    2007-01-01

    Full Text Available The increasing number of autochthonous cases of Chagas disease in the Amazon since the 1970s has led to fear that the disease may become a new public health problem in the region. This transformation in the disease's epidemiological pattern in the Amazon can be explained by environmental and social changes in the last 30 years. The current article draws on the sociological theory of perverse effects to explain these changes as the unwanted result of the shift from the "inward" development model prevailing until the 1970s to the "outward" model that we know as globalization, oriented by industrial forces and international trade. The current article highlights the implementation of five new patterns in agriculture, cattle-raising, mining, lumbering, and urban occupation that have generated changes in the environment and the traditional indigenous habitat and have led to migratory flows, deforestation, sedentary living, the presence of domestic animals, and changes in the habitat that facilitate colonization of human dwellings by vectors and the domestic and work-related transmission of the disease. The expansion of Chagas disease is thus a perverse effect of the globalization process in the Amazon.El incremento de casos autóctonos de la enfermedad de Chagas en la Amazonia a partir de los años setenta hace temer que pueda convertirse en un novedoso problema de salud pública en la región. Este cambio del patrón epidemiológico de la enfermedad en la región amazónica debe ser explicado por las transformaciones ambientales y sociales que han ocurrido en los pasados treinta años. Este artículo utiliza la teoría sociológica de los efectos perversos para explicar esos cambios como el resultado indeseado del cambio de modelo de desarrollo "hacia adentro", que había existido hasta los años setenta, por otro "hacia fuera" que está orientado por las fuerzas de la producción y el comercio internacional que conocemos como globalización. El art

  14. Landscape dynamics in northwestern Amazonia: an assessment of pastures, fire and illicit crops as drivers of tropical deforestation.

    Science.gov (United States)

    Armenteras, Dolors; Rodríguez, Nelly; Retana, Javier

    2013-01-01

    Many studies have identified drivers of deforestation throughout the tropics and, in most cases, have recognised differences in the level of threat. However, only a few have also looked at the temporal and spatial dynamics by which those drivers act, which is critical for assessing the conservation of biodiversity as well as for landscape planning. In this study, we analyse land cover change between 2000 and 2009 in north-western Colombian Amazonia to identify the interactions between the use of fire, cultivation of illicit crops and establishment of pastures, and their impacts on the loss of forest in the region. Yearly analyses were undertaken at randomly selected sample areas to quantify the average areas of transition of land cover types under different landscape compositions: forest-dominated mosaics, pasture mosaics, fire mosaics, and illicit crop mosaics. Our results indicate that despite the fact that forest areas were well-preserved, deforestation occurred at a low annual rate (0.06%). Conversion to pasture was the main factor responsible for forest loss (the area of pastures tripled within forest mosaics over 8 years), and this process was independent of the landscape matrix in which the forests were located. In fire mosaics, burning is a common tool for forest clearing and conversion to pasture. Thus, forests in fire mosaics were highly disturbed and frequently transformed from primary to secondary forests. The use of fire for illicit cropping was not detected, partly due to the small size of common illicit crops. Forest regeneration from pastures and secondary vegetation was observed in areas with large amounts of natural forest. Overall, assuming the continuation of the observed pasture conversion trend and the use of forest fire, we suggest that our results should be incorporated into a spatially explicit and integrated decision support tool to target and focus land-planning activities and policies.

  15. Desmatamento na Amazônia: dinâmica, impactos e controle Deforestation in Amazonia: dynamics, impacts and control

    Directory of Open Access Journals (Sweden)

    Philip M. Fearnside

    2006-01-01

    Full Text Available O desmatamento na Amazônia procede a um alto ritmo por várias razões, muitas das quais dependem de decisões do governo. O desmatamento leva à perda de serviços ambientais, que têm um valor maior que os usos pouco sustentáveis que substituem a floresta. Estes serviços incluem a manutenção da biodiversidade, da ciclagem de água e dos estoques de carbono que evitam o agravamento do efeito estufa. Retroalimentações entre as mudanças climáticas e a floresta, por meio de processos tais como os incêndios florestais, a mortalidade de árvores por seca e calor e a liberação de estoques de carbono no solo, representam ameaças para o clima, a floresta e a população brasileira. Eventos recentes indicam que o desmatamento pode ser controlado, tendo a vontade política, pois os processos subjacentes dependem de decisões humanas.Deforestation in Amazonia proceeds at a rapid rate for various reasons, many of which depend on government decisions. Deforestation causes losses of environmental services that are more valuable than the short-lived uses that replace the forest. These services include maintenance of biodiversity, of water cycling and of the stocks of carbon that avoid further intensification of the greenhouse effect. Feedbacks between climatic changes and the forest through such processes as forest fires, tree mortality from drought and heat and the release of carbon stocks in the soil represent dangers for the climate, the forest and the Brazilian population. Recent events indicate that deforestation can be controlled, given the political will, because the underlying processes depend on human decisions.

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

    Science.gov (United States)

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

    2015-10-01

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

  17. Activity budget, diet, and use of space by two groups of squirrel monkeys (Saimiri sciureus) in eastern Amazonia.

    Science.gov (United States)

    Pinheiro, Tatyana; Ferrari, Stephen F; Lopes, Maria Aparecida

    2013-07-01

    Squirrel monkeys (Saimiri spp.) are widely distributed in the Amazon basin. This study describes the ecological and behavioral patterns of two social groups of S. sciureus in forests adjacent to the Tucuruí hydroelectric reservoir in eastern Amazonia, including range size, activity budgets, and composition of the diet. The groups were monitored at Base 4 (group B4) and Germoplasma Island (group GI). Quantitative behavioral data were collected using instantaneous scan sampling to record behavior, substrate use, and height. Home ranges were delimited using a GPS to determine group position after each 50 m of movement. Home ranges were 75.0 ha for group B4 (39 members) and 77.5 ha for group GI (32 members). The use of vertical strata was well defined, with a marked preference for the middle and lower levels of the canopy. The activity budgets of both groups were typical of those of other squirrel monkeys and were dominated by foraging (B4 = 48.7 %; GI = 49.6 %), moving (both groups 28.9 %), and feeding (B4 = 14.6 %; GI = 12.4 %). Resting was rare (B4 = 3.5 %; GI = 2.6 %) and less common than social behavior (B4 = 4.3 %; GI = 6.4 %). The diet of both groups was dominated by plant material (B4 = 70.7 % of feeding records; GI = 71.4 %), which is in contrast with the more insectivorous diets recorded for Saimiri at other sites. Group GI spent more time foraging during the dry season, whereas group B4 spent more time in the rainy season when the consumption of fruit increased (significantly, in the case of group GI). The less insectivorous diet of these groups may be due to a number of factors, including the unique habitat configuration at the site and reduced hydrological stress due to the proximity of the reservoir.

  18. Late Quaternary sedimentary dynamics in Western Amazonia: Implications for the origin of open vegetation/forest contrasts

    Science.gov (United States)

    Rossetti, D. F.; Bertani, T. C.; Zani, H.; Cremon, E. H.; Hayakawa, E. H.

    2012-12-01

    This work investigated the evolution of sedimentary environments during the latest Quaternary and their influence on the paradoxical occurrence of open vegetation patches in sharp contact with the Amazonian forest. The approach integrated pre-existing geological and floristic data from lowlands in the Brazilian Amazonia, with remote sensing imagery including multispectral optical images (TM, ETM+, and ASTER), Phased Array L-band Synthetic Aperture Radar (PALSAR), InSAR C-band SRTM-DEMs, and high resolution images obtained from Google Earth™. The detection of an abundance of paleomorphologies provided evidence of a scenario in which constant environmental shifts were linked to the evolution of fluvial and megafan depositional systems. In all studied areas, the open vegetation patches are not random, but associated with sedimentary deposits representative of environments either deactivated during the Holocene or presently in the process of deactivation. Sedimentary evolution would have determined the distribution of wetlands and terra firme in many areas of the Amazonian lowlands, and would have a major impact on the development of open vegetated patches within the modern rainforest. Subsiding areas were filled up with megafan deposits, and many fluvial tributaries were rearranged on the landscape. The close relationship between vegetation and the physical environment suggests that sedimentary history related to the evolution of depositional settings during the latest Quaternary played a major role in the distribution of flooded and non-flooded areas of the Amazonian lowlands, with a direct impact on the distribution of modern floristic patterns. As the depositional sites were abandoned and their sedimentary deposits were exposed to the surface, they became sites suitable for vegetation growth, first of herbaceous species and then of forest. Although climate fluctuations might have been involved, fault reactivation appears to have been the main cause of changes in

  19. High-resolution mitochondrial DNA analysis sheds light on human diversity, cultural interactions, and population mobility in Northwestern Amazonia.

    Science.gov (United States)

    Arias, Leonardo; Barbieri, Chiara; Barreto, Guillermo; Stoneking, Mark; Pakendorf, Brigitte

    2018-02-01

    Northwestern Amazonia (NWA) is a center of high linguistic and cultural diversity. Several language families and linguistic isolates occur in this region, as well as different subsistence patterns, with some groups being foragers and others agriculturalists. In addition, speakers of Eastern Tukanoan languages are known for practicing linguistic exogamy, a marriage system in which partners are taken from different language groups. In this study, we use high-resolution mitochondrial DNA sequencing to investigate the impact of this linguistic and cultural diversity on the genetic relationships and population structure of NWA groups. We collected saliva samples from individuals representing 40 different NWA ethnolinguistic groups and sequenced 439 complete mitochondrial genomes to an average coverage of 1,030×. The mtDNA data revealed that NWA populations have high genetic diversity with extensive sharing of haplotypes among groups. Moreover, groups who practice linguistic exogamy have higher genetic diversity, while the foraging Nukak have lower genetic diversity. We also find that rivers play a more important role than either geography or language affiliation in structuring the genetic relationships of populations. Contrary to the view of NWA as a pristine area inhabited by small human populations living in isolation, our data support a view of high diversity and contact among different ethnolinguistic groups, with movement along rivers probably facilitating this contact. Additionally, we provide evidence for the impact of cultural practices, such as linguistic exogamy, on patterns of genetic variation. Overall, this study provides new data and insights into a remote and little-studied region of the world. © 2017 Wiley Periodicals, Inc.

  20. central t

    Directory of Open Access Journals (Sweden)

    Manuel R. Piña Monarrez

    2007-01-01

    Full Text Available Dado que la Regresión Ridge (RR, es una estimación sesgada que parte de la solución de la regresión de Mínimos Cuadrados (MC, es vital establecer las condiciones para las que la distribución central t de Student que se utiliza en la prueba de hipótesis en MC, sea también aplicable a la regresión RR. La prueba de este importante resultado se presenta en este artículo.

  1. Central sleep apnea

    Science.gov (United States)

    Sleep apnea - central; Obesity - central sleep apnea; Cheyne-Stokes - central sleep apnea; Heart failure - central sleep apnea ... Central sleep apnea results when the brain temporarily stops sending signals to the muscles that control breathing. The condition ...

  2. Aspectos agronómicos sobre el cultivo del arazá (eugenia stipitata me vaugh Frutal promisorio de la amazonia colombiana

    Directory of Open Access Journals (Sweden)

    Quevedo Garcia Enrique

    1995-06-01

    Full Text Available

    En este trabajo se presenta un estudio del manejo agronómico del cultivo del arazá (Eugenia slipitata Mc. Vaugh en la Amazonia colombiana y una revisión del manejo del arazá en la Amazonia del Brasil y Perú. Se concluye que esta es una especie en vía de domesticación que puede ser cultivada en otras regiones de Colombia y que podría ser un sustituto para los cultivos ilícitos. Si somos hábiles en logra establecer el cultivo del arazá. En reglones con características ecológicas adecuadas para esta especie en corto tiempo, obtendremos un fruto para el consumo humano y su usa extensivo en Colombia.

  3. Abundancia de actinomicetes y micorrizas arbusculares en paisajes fragmentados de la Amazonia colombiana

    Directory of Open Access Journals (Sweden)

    Cardona Gladys I. Cardona

    2005-12-01

    ="Subtle Emphasis" />

    Se evalúo la abundancia de actinomicetes y hongos Micorriza Arbuscular (MA en suelos bajo coberturas de bosque y pasto, en una zona de colonización de la Amazonia colombiana con tres grados de transformación antrópica. Se realizó una estratificación espacial de la fragmentación del paisaje de tierra firme, en cercanías de San Jos

  4. Food resource partitioning in a fish community of the central Amazon floodplain

    Directory of Open Access Journals (Sweden)

    Bernard de Mérona

    Full Text Available Diets of most of fish species inhabiting a floodplain lake in central Amazonia were studied over a two years and half period. Based on the percentage of relative occurrence of 11 major food categories a classification of species in 11 feeding guilds is proposed. Many species were found to be specialized feeders. Fish, detritus and insects were the most important food resources supporting the fish community in both seasons, but the proportions of fruits, invertebrates and fish were reduced during the low water season. At the community level mean diet overlap between species was low, suggesting efficient resource partitioning within the community. However mean overlap between unspecialized feeders was high. Based on the 23 most abundant species belonging to the different feeding guilds, there was no difference in mean overlap between seasons. Whereas individual species exhibited diet changes between high water and low water seasons, there was no general pattern of seasonal change within feeding guilds.

  5. Effect of isodillapiole on the expression of the insecticide resistance genes GSTE7 and CYP6N12 in Aedes aegypti from central Amazonia.

    Science.gov (United States)

    Lima, V S; Pinto, A C; Rafael, M S

    2015-12-11

    The yellow fever mosquito Aedes (Stegomyia) aegypti is the main vector of dengue arbovirus and other arboviruses. Dengue prevention measures for the control of A. aegypti involve mainly the use of synthetic insecticides. The constant use of insecticides has caused resistance in this mosquito. Alternative studies on plant extracts and their products have been conducted with the aim of controlling the spread of the mosquito. Dillapiole is a compound found in essential oils of the plant Piper aduncum (Piperaceae) which has been effective as a biopesticide against A. aegypti. Isodillapiole is a semisynthetic substance obtained by the isomerization of dillapiole. In the present study, isodillapiole was evaluated for its potential to induce differential expression of insecticide resistance genes (GSTE7 and CYP6N12) in 3rd instar larvae of A. aegypti. These larvae were exposed to this compound at two concentrations (20 and 40 μg/mL) for 4 h during four generations (G1, G2, G3, and G4). Quantitative RT-PCR was used to assess the expression of GSTE7 and CYP6N12 genes. GSTE7 and CYP6N12 relative expression levels were higher at 20 than at 40 μg/mL and varied among generations. The decrease in GSTE7 and CYP6N12 expression levels at the highest isodillapiole concentration suggests that larvae may have suffered from metabolic stress, revealing a potential alternative product in the control of A. aegypti.

  6. Tree species effects on soil properties and greenhouse gas fluxes in East-central Amazonia: comparison between monoculture and diverse forest

    Science.gov (United States)

    J. Van Haren; R.C. de Oliveira, Jr.; P.T. Beldini; P.B. de Camargo; M. Keller; S. Saleska

    2013-01-01

    Tropical plantations are considered a viable option to sequester carbon on abandoned agricultural lands, but implications of tree species selection for overall greenhouse gas budgets on plantations have been little studied. During three wet seasons, we investigated the influence of nine tree species on soil pH, temperature (ST), bulk density (BD), moisture content...

  7. Soil water storage and groundwater behaviour in a catenary sequence beneath forest in central Amazonia: I. Comparisons between plateau, slope and valley floor

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    M. G. Hodnett

    1997-01-01

    Full Text Available Soil water storage was monitored in three landscape elements in the forest (plateau, slope and valley floor over a 3 year period to identify differences in sub-surface hydrological response. Under the plateau and slope, the changes of storage were very similar and there was no indication of surface runoff on the slope. The mean maximum seasonal storage change was 156 mm in the 2 m profile but it was clear that, in the dry season, the forest was able to take up water from below 3.6 m. Soil water availability was low. Soil water storage changes in the valley were dominated by the behaviour of a shallow water table which, in normal years, varied between 0.1 m below the surface at the end of the wet season and 0.8 m at the end of the dry season. Soil water storage changes were small because root uptake was largely replenished by groundwater flow towards the stream. The groundwater behaviour is controlled mainly by the deep drainage from beneath the plateau and slope areas. The groundwater gradient beneath the slope indicated that recharge beneath the plateau and slope commences only after the soil water deficits from the previous dry season have been replenished. Following a wet season with little recharge, the water table fell, ceasing to influence the valley soil water storage, and the stream dried up. The plateau and slope, a zone of very high porosity between 0.4 and 1.1 m, underlain by a less conductive layer, is a probable route for interflow during, and for a few hours after, heavy and prolonged rainfall.

  8. Rehabilitation of a bauxite tailing substrate in Central Amazonia: The effect of litter and seed addition on flood-prone forest restoration.

    NARCIS (Netherlands)

    Dias, A.; Bozelli, R.L.; Darigo, R.M.; Esteves, F. de A.; Santos, H.F. dos; Figueredo-Barros, M.P.; Nunes, M.F.Q.S.; Roland, F.; Zamith, L.R.; Scarano, F.R.

    2012-01-01

    Impacts of mining activity can be particularly difficult to remediate in wetland ecosystems subject to inundation pulses due to the reduced length of the plant growing season. We used a factorial experiment to test whether litter and seed addition could be used to increase the efficiency of

  9. Central hypothyroidism

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    Vishal Gupta

    2011-01-01

    Full Text Available Central hypothyroidism is defined as hypothyroidism due to insufficient stimulation by thyroid stimulating hormone (TSH of an otherwise normal thyroid gland. It has an estimated prevalence of approximately 1 in 80,000 to 1 in 120,000. It can be secondary hypothyroidism (pituitary or tertiary hypothyroidism (hypothalamus in origin. In children, it is usually caused by craniopharyngiomas or previous cranial irradiation for brain tumors or hematological malignancies. In adults, it is usually due to pituitary macroadenomas, pituitary surgeries or post-irradiation. Fatigue and peripheral edema are the most specific clinical features. Diagnosis is established by the presence of normal to low-normal TSH on the background of low-normal thyroid hormones, confirmed by the thyrotropin releasing hormone stimulation test. Therapy includes use of levothyroxine titrated to improvement in symptomology and keeping free T4 in the upper limit of normal reference range.

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

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    G. Penido

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

  11. Decay of interspecific avian flock networks along a disturbance gradient in Amazonia

    Science.gov (United States)

    Mokross, Karl; Ryder, Thomas B.; Côrtes, Marina Corrêa; Wolfe, Jared D.; Stouffer, Philip C

    2014-01-01

    Our understanding of how anthropogenic habitat change shapes species interactions is in its infancy. This is in large part because analytical approaches such as network theory have only recently been applied to characterize complex community dynamics. Network models are a powerful tool for quantifying how ecological interactions are affected by habitat modification because they provide metrics that quantify community structure and function. Here, we examine how large-scale habitat alteration has affected ecological interactions among mixed-species flocking birds in Amazonian rainforest. These flocks provide a model system for investigating how habitat heterogeneity influences non-trophic interactions and the subsequent social structure of forest-dependent mixed-species bird flocks. We analyse 21 flock interaction networks throughout a mosaic of primary forest, fragments of varying sizes and secondary forest (SF) at the Biological Dynamics of Forest Fragments Project in central Amazonian Brazil. Habitat type had a strong effect on network structure at the levels of both species and flock. Frequency of associations among species, as summarized by weighted degree, declined with increasing levels of forest fragmentation and SF. At the flock level, clustering coefficients and overall attendance positively correlated with mean vegetation height, indicating a strong effect of habitat structure on flock cohesion and stability. Prior research has shown that trophic interactions are often resilient to large-scale changes in habitat structure because species are ecologically redundant. By contrast, our results suggest that behavioural interactions and the structure of non-trophic networks are highly sensitive to environmental change. Thus, a more nuanced, system-by-system approach may be needed when thinking about the resiliency of ecological networks. PMID:24335983

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

    Science.gov (United States)

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

    2015-05-01

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

  13. Crecimiento del maíz en vertisoles con alto aluminio en la Baixada Maranhense pre-Amazonia, Brasil.

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    Alessandro Costa-da Silva

    2014-07-01

    Full Text Available El objetivo de este trabajo fue evaluar el crecimiento del maíz en suelos con alto contenido de aluminio. Se midió el efecto del Al3+ en raíces y la cantidad de materia seca (raíz, hoja y tallo de maíz. Se efectuó la caracterización físico-química de cuatro muestras de suelo con alto aluminio colectadas del horizonte Ap, en tres municipios de la región conocida como Baixada Maranhense (Pre-Amazonia, Brasil: Santa Rita (SR, Arari (AR y Vitoria do Mearim (VM y un testigo colectado en el municipio de São Luís, Área del Núcleo de Tecnología Rural (T. El estudio, ejecutado en 2009, se llevó a cabo en invernadero y se utilizó 2 dm3 de suelo por maceta. Asimismo las muestras fueron divididas en muestras con y sin fertilización. La variación en la longitud de la raíz y de materia seca de las hojas difirió significativamente entre tratados con y sin fertilizante, excepto en la muestra de la localidad T. La producción de materia seca de raíz, tallo y hoja fue mayor en todos los suelos cuando se fertilizó. El suelo testigo también superó a todos los demás en cuanto a producción de materia seca en la raíz, posiblemente como resultado de una menor cantidad de Al3+ (1,2 cmolc/dm3 en comparación con los suelos SR, AR y VM (6,8; 8,0 y 7,0 cmolc/dm3 respectivamente. Se concluye la fertilización reduce el efecto detrimental del aluminio en la producción de maíz en la Baixada Maranhense.

  14. Treating leishmaniasis in Amazonia: A review of ethnomedicinal concepts and pharmaco-chemical analysis of traditional treatments to inspire modern phytotherapies.

    Science.gov (United States)

    Odonne, Guillaume; Houël, Emeline; Bourdy, Geneviève; Stien, Didier

    2017-03-06

    Cutaneous and mucocutaneous leishmaniasis are neglected tropical diseases that occur in all intertropical regions of the world. Amazonian populations have developed an abundant knowledge of the disease and its remedies. Therefore, we undertook to review traditional antileishmanial plants in Amazonia and have developed new tools to analyze this somewhat dispersed information. A literature review of traditional remedies for cutaneous/mucocutaneous leishmaniasis in the Amazon was conducted and the data obtained was used to calculate distribution indexes designed to highlight the most relevant uses in Amazonia. The cultural distribution index represents the distribution rate of a given taxon among different cultural groups and was calculated as the ratio of the number of groups using the taxon to the total number of groups cited. The geographical distribution index allowed us to quantify spatial distribution of a taxon's uses in Amazonia and was calculated geometrically by measuring the average distance between the points where uses have been reported and the barycenter of those points. The general distribution index was defined as an arithmetic combination of the previous two and provides information on both cultural and spatial criteria. 475 use reports, concerning 291 botanical species belonging to 83 families have been gathered depicted from 29 sources. Uses concern 34 cultural groups. While the use of some taxa appears to be Pan-Amazonian, some others are clearly restricted to small geographical regions. Particular attention has been paid to the recipes and beliefs surrounding treatments. Topical application of the remedies dominated the other means of administration and this deserves particular attention as the main treatments against Neotropical leishmaniasis are painful systemic injections. The data set was analyzed using the previously defined distribution indexes and the most relevant taxa were further discussed from a phytochemical and pharmacological point

  15. Notes on the insect fauna on two species of astrocaryum (palmae, cocoeae, bactridinae in peruvian amazonia, with emphasis on potential pests of cultivated palms

    Directory of Open Access Journals (Sweden)

    1992-01-01

    Full Text Available NOTES SUR LA FAUNE ENTOMOLOGIQUE DE DEUX ESPÈCES D'ASTROCARYUM (PALMAE, COCOEAE, BACTRIDINAE DE L'AMAZONIE PÉRUVIENNE, ET MISE EN ÉVIDENCE DE RAVAGEURS POTENTIELS DES PALMIERS CULTIVÉS. La faune entomologique des palmiers Astrocaryum chanta et Astrocaryum carnosum a été étudiée dans deux sites différents de l'Amazonie péruvienne : région de Jenaro Herrera sur le bas Ucayali pour la première espèce, et région d'Uchiza sur le haut Huallaga pour la seconde. Cette faune est extrêmement diversifiée. Elle comprend de nombreuses espèces d'insectes connues comme ravageurs des palmiers cultivés, ainsi que d'autres espèces de phytophages dont les plantes hôtes n'étaient pas encore connues. De nombreuses autres espèces d'insectes, prédateurs ou de niveau trophique mal défini, font aussi partie de la biocénose des palmiers étudiés. Astrocaryum chanta et Astrocaryum carnosum sont considérés comme foyers d'infestation en ravageurs pour les plantations industrielles de palmiers en Amazonie péruvienne. NOTAS SOBRE LA FAUNA DE INSECTOS DE DOS ESPECIES DE ASTROCARYUM (PALMAE, COCOEAE, BACTRIDINAE EN LA AMAZONIA PERUANA, CON ÉNFASIS EN LAS PLAGAS POTENCIALES DE LAS PALMERAS CULTIVADAS. La fauna de insectos de las palmas Astrocaryum chonta y Astrocaryum carnosum se ha estudiado en dos lugares diferentes de la Amazonia peruana: en la región de Jenaro Herrera, bajo Ucayali para la primera especie, y en la región de Uchiza, alto Huallaga para la segunda. Esta fauna es extremadamente diversificada. Incluye numerosas especies de insectos conocidos como depredadores de las palmas cultivadas, así como otras especies de fitófagos cuyas plantas hospedantes aún no eran conocidas. Numerosas especies de otros insectos, depredadores o de un nivel trófico mal definido, forman parte también de la biocenosis de las palmas estudiadas. Astrocaryum chonta y Astrocaryum carnosum son considerados como focos de infestación de depredadores para las

  16. VILLAGE’S HERDS: INVESTIGATING THE INTRODUCTION OF DOMESTIC ANIMALS AND PATTERNS OF ANIMAL HUSBANDRY AMONG INDIGENOUS PEOPLES IN AMAZONIA (RONDÔNIA

    Directory of Open Access Journals (Sweden)

    Felipe Ferreira Vander Velden

    2011-06-01

    Full Text Available This paper discuss the introduction of European domestic animals in indigenous villages in the Amazon, with particular stress on groups in Rondonia, specially the Karitiana, a Tupi-Arikém-speaking people that lives in the north of that state. In what concerns the history of Brazilian territorial conquest, marked by the ‘frentes pastoris’’ great narrative, and the present expansion – material and also ideological – of husbandry throughout Amazonia, this article points to many questions about the position of these animals – above all cattle – in indigenous peoples’ symbolical and material universes. Suggests new investigative possibilities, that inquires not only implemented experiences with animal husbandry in indigenous villages, but also desires and projects designed to future implementations.

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

    Science.gov (United States)

    Brown, I.

    2002-12-01

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

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

    Science.gov (United States)

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

    2017-12-01

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

  19. ESTRUCTURA POBLACIONAL DE LA PALMA IRIARTEA DELTOIDEA, EN UN BOSQUE DE TIERRA FIRME DE LA AMAZONIA COLOMBIANA

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    Gonzalez Roy

    2012-06-01

    Full Text Available El objetivo de esta investigación fue caracterizar la densidad y la estructura poblacional de la palma bombona Iriartea deltoidea en un bosque de tierra firme de la zona sur del Parque Nacional Natural Amacayacu, en la Amazonia Colombiana. En seis parcelas de 1 ha y 90 transectos de 50 x 1 m, se censaron todos los individuos de la especie. Para cada individuo, se registró la altura del tallo, el estado morfológico de las hojas (i.e. hojas enteras, hojas divididas, forma de las pinnas, la formación de raíz fúlcrea, la altura del cono de la raíz y el estado fenol��gico (brácteas, inflorescencias e infrutescencias. Se encontraron 2819 individuos (376±58 ind/ha que se agruparon en tres grandes categorías de edad significativamente diferentes (e.g. plántulas, juveniles y adultos. La gran categoría Plántulas se caracterizó por individuos con hojas no divididas, sin formación de raíces fúlcreas y comprendió el 96.6% de los individuos muestreados. Esta se subdividió en seis categorías de plántulas estadísticamente significativas dadas por cambios en la altura, número y morfología de las hojas. La gran categoría Juvenil consistió en individuos con hojas divididas en pinnas, formación de raíces fúlcreas con altura de cono radicular menor a 1 m, sin estructuras reproductivas y con 1.5% (42 de los individuos totales. Esta se subdividió en dos categorías de juveniles (I y II. La categoría Adultos incluyó todos los individuos con hojas divididas en pinnas, formación de raíces fúlcreas con altura del cono radicular mayor a 1 m y con presencia de estructuras reproductivas. Estos correspondieron al 1.9% (54 de los individuos y se subdividieron en dos categorías: Adultos I y Adultos II, dadas principalmente por diferencias significativas en la altura. La densidad de la población presentó una distribución típica de poblaciones naturales de plantas tropicales, siguiendo un modelo de Poisson en donde abundan individuos de

  20. Numerical analysis of palynological data from Neogene fluvial sediments as evidence for rainforest dynamics in western Amazonia

    Science.gov (United States)

    Salamanca, Sonia; van Manen, Milan; Hoorn, Carina

    2014-05-01

    Deep-time records that give an insight into the composition and dynamics of the ancestral Amazon rain forest are rare. Yet to understand the modern biodiversity patterns it is important to untangle the long-term evolution of this forest. Sampling Neogene strata requires drilling operations or complex fieldwork along the rivers where outcrops generally are small. In the nineties an exceptionally good exposure of fluvial sediments of early Miocene age (17.7-16.1 Ma) was documented near the island of Mariñame (Caquetá River, Colombian Amazonia) (Hoorn, 1994). This 60 m sediment succession consists of quartz-rich sands with a circa 10 m black, sandy clay intercalation. Palynomorphs are well preserved in these organic-rich clays and palynological analysis indicated high pollen diversity and changes in composition following changes in the sedimentary environment and water composition (see van Soelen et al., this session). A numerical analysis in R (2013) of the existing data, using a number of multivariate and other statistical techniques now shows a gradient of change in the composition of the Miocene palynological assemblages. Non-metric-multidimensional scaling using distance matrixes (Oksanen, 2012) and their visualizations in correlograms (Friendly, 2002) indicate that the regional (palm) swamp forests of Mauritiides franciscoi (Mauritia), frequently found together with other palms such as Psilamonocolpites amazonicus (Euterpe?) and Psilamonocolpites rinconii, were affected by a marine incursion. The latter is suggested by the change of composition and the presence of estuarine elements such as Zonocostites ramonae (Rhizophora), foraminifer linings and dinoflagellate cysts, which became common during the marine event. In the older part of the section, and at the top, Rhoipites guianensis (Sterculiaceae/Tiliaceae) is quite abundant, in contrast with the relatively low abundance of M. franciscoi. The numerical analysis allowed us to: a) group the pollen data into 3

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

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    E. T. Sena

    2013-02-01

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

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

  2. El mercurio en la amazonia boliviana : sintesis del conocimiento sobre la contaminacion por mercurio en aguas, sedimentos y peces del rio Beni y sus tributarios, impactos sobre las poblaciones riberenas; C 010057498

    OpenAIRE

    Maurice Bourgoin, Laurence; Quiroga, I. (collab.); Alanoca, L. (collab.); Flores, L. (collab.); Chincheros, J. (collab.)

    2001-01-01

    La contaminacion por mercurio de los rios constituye un problema cada vez mas preocupante en toda la cuenca amazonica. Este mercurio tiene origenes naturales como las emisiones volcanicas o termales, la disolucion de algunas rocas o la erosion de los suelos que, en esta zona del mundo, presentan concentraciones en metales pesados muy elevadas. El mercurio puede provenir tambien de las actividades de explotacion auriferas, cada vez mas numerosas en la Amazonia, region afectada por la "fiebre d...

  3. Use of AFLPS to distinguish landraces of pejibaye (Bactris gasipaes in brazilian Amazonia Uso de AFLPS para discriminar raças primitivas de pupunha (Bactris gasipaes na Amazônia brasileira

    Directory of Open Access Journals (Sweden)

    Charles R. Clement

    2002-12-01

    Full Text Available Although the first inhabitants of western Amazonia domesticated pejibaye (Bactris gasipaes Kunth, Palmae or peach palm for its fruits, today it is widely planted for its heart-of-palm. Like other domesticates, pejibaye presents a complex hierarchy of landraces developed before the conquest of the Americas. The existence of three landraces (Pará, Solimões, Putumayo was proposed along the Amazonas and Solimões Rivers, Brazil, based on morphological characteristics. There are some questions remaining about the intermediate landrace being an artifact of the morphometric analysis. AFLPs were used to evaluate the relationships among samples of these putative landraces. DNA was extracted from 99 plants representing 13 populations maintained in the Pejibaye Germplasm Bank, Manaus, AM; six primer combinations generated 245 markers via PCR, which were scored in an ABI Prism 310 sequencer and analyzed with GeneScan Software; Jaccard similarities were estimated and a dendrogram was generated with UPGMA. Two groups of plants were observed in the dendrogram instead of three, and were similar at 0.795. Each group contained two subgroups, similar at 0.815. One group (n=41 contained 73% Pará landrace plants, with one subgroup (n=22 containing 91% Pará, and the other (n=19 containing 53% Pará. The other group (n=58 contained 53% Solimões and 40% Putumayo landrace plants, with one subgroup (n=21 containing 52% Solimões and 43% Putumayo, and the other (n=35 containing 57% Solimões and 37% Putumayo. The first group confirmed the Pará landrace. The second group suggested that the Solimões landrace does not exist, but that the Putumayo landrace extends along the Solimões River to Central Amazonia.Os primeiros povos da Amazônia ocidental domesticaram a pupunha (Bactris gasipaes Kunth, Palmae por seu fruto, embora hoje seja muito plantada por seu palmito. Como outros cultivos domesticados, a pupunha apresenta uma hierarquia complexa de raças primitivas

  4. New Allometric Equations to Support Sustainable Plantation Management of Rosewood (Aniba rosaeodora Ducke in the Central Amazon

    Directory of Open Access Journals (Sweden)

    Pedro Krainovic

    2017-09-01

    Full Text Available Rosewood (Aniba rosaeodora Ducke is an endangered Amazonian tree species which produces one of the most valuable essential oils in the world. The species is used in silvicultural systems which are seen as a means to reducing the pressure of exploitation of natural rosewood populations. There are no specific equations for rosewood plantations, and therefore generalized equations are inappropriate for the species in commercial systems. This study presents allometric equations from 144 trees sampled in different rosewood plantations of Central Amazonia. The equations generated were compared with an equation used in forest management to estimate wood volume and another one recommended by law for rosewood biomass. The equation suggested by current legislation underestimates the actual values by more than 70% making the viable use of this equation impossible in commercial plantations. The equations generated to estimate the volume and biomass serve as an alternative to the need to develop specific equations for each area and age of the plant. The generic equation for the species is consistent for fresh mass management, with a generalized R2 of 0.80 and an underestimation of 0.33%. The equation for crown fresh mass estimation presented a generalized R2 of 0.32 and an underestimation of 0.24%. The underestimation of the mass production by rosewood plantations represents a serious impediment to this forest activity. The allometric equations developed are highly applicable under different conditions and management options and should be suggested by the legal provisions regulating rosewood-related activity in Central Amazonia.

  5. Central Nervous System Vasculitis

    Science.gov (United States)

    ... of Vasculitis / Central Nervous System (CNS) Vasculitis Central Nervous System (CNS) Vasculitis Swap out your current Facebook Profile ... Facebook personal page. Replace with this image. Central nervous system (CNS) vasculitis is inflammation of blood vessel walls ...

  6. Uso de florestas secundárias por aves de sub-bosque em uma paisagem fragmentada na Amazônia central Use of secondary forests by understory birds in a fragmented landscape in central Amazonia

    Directory of Open Access Journals (Sweden)

    João Vitor Campos e Silva

    2012-03-01

    Full Text Available Na Amazônia, as taxas de desmatamento crescem desde 1991 e as previsões não são otimistas quanto à desaceleração desse processo. A devastação da floresta é acompanhada de uma expansão de florestas secundárias (FS que se estabelecem nas áreas abandonadas. A tendência é um aumento de florestas secundárias, resultando num mosaico de floresta contínua e fragmentos separados por uma matriz de FS. Nesse cenário, autores acreditam que a Amazônia pode passar por um processo massivo de extinção de espécies. Por outro lado, a previsão de um processo massivo de extinção pode ser equivocada, pois muitas espécies florestais poderiam sobreviver nas florestas secundárias. Para avaliar o valor das florestas secundárias para espécies florestais amostramos por oito meses com redes de neblina uma capoeira (FS em regeneração e uma floresta primária (FP de uma paisagem fragmentada. Algumas espécies não foram capturadas na capoeira e aparentemente evitam esse tipo de hábitat. No entanto, a maioria das espécies do grupo focal não apresentou diferença na sobrevivência aparente entre os ambientes, o que nos indica que estão habitando a capoeira e a floresta primária da mesma forma. Na realidade amazônica, onde grande parte da matriz é composta por floresta secundária, a matriz tem valor para conservação e deve ser analisada como um elemento dinâmico que não apenas permite a movimentação de indivíduos, mas também serve de hábitat para muitas espécies de floresta primária. Mas ressaltamos que é fundamental a preservação de áreas de floresta primária que servirão de fonte às florestas secundárias adjacentes.Rates of deforestation in the Brazilian Amazon have increased since 1991 and forecasts are not optimistic about the slowing of this process. Some authors believe that the Amazon may be experiencing a massive process of species extinction. However, the deforestation is accompanied by the expansion of secondary forests that are established in the abandoned areas. The trend is an increase in secondary forests cover, resulting in a mosaic of primary forest (FP and fragments separated by an array of secondary forests (FS. In this scenario, the prediction of a massive extinction could be wrong if many species could survive in the secondary forests. To assess the importance of FS for the understory birds we sampled areas in regeneration and a continuous forest of a fragmented landscape. We conducted mist netting (24 nets/day for six consecutive days/month, for 8 months (May-November in 2009. Some forest species as do not seem to be adapted to the secondary forest environment and their occurrences are restricted to continuous forest environments. But most focal species showed no significant difference in apparent survival rates between the enviroments, suggesting that these species inhabit the secondary forest and the primary forest similarly. Because most of the matrix in fragmented landscapes are composed by secondary forests, such results highlights the conservation value that these habitats present in the long term. Thus, FS should be regarded as dynamic matrix that not only allows the movement of individuals but also function as habitat for many species typical of FP.

  7. Bees visitors of three species of Clusia (Clusiaceae flowers in Central Amazonia Abelhas visitantes de flores de três espécies de Clusia (Clusiacea na Amazônia Central

    Directory of Open Access Journals (Sweden)

    Ana Claudia Kaminski

    2006-01-01

    Full Text Available Observations on bees visitors to three species of Clusia (Clusiaceae flowers in the Reserva Adolpho Ducke, Manaus, Amazonas, Brazil were made during three two-week periods. The three species of Clusia, namely C. grandiflora, C. panapanari and C. insignis, presented variations regarding the species of bee visitors. A total of 23 bee species visited the three species of Clusia. The Euglossini and Meliponinae bees were the most frequent visitors of the Clusia flowers. Bee collecting behavior of floral resources is described.Durante seis semanas foram realizadas observações das abelhas visitantes de flores de três espécies de Clusia (Clusiaceae, na Reserva Florestal Adolpho Ducke, em Manaus. As três espécies de Clusia: C. grandiflora Splitg., C. panapanari (Aubl. e C. insignis Mart. apresentaram diferenças com relação às visitas de espécies de abelhas, tendo sido visitadas por 23 espécies. Abelhas Euglossini e Meliponinae foram os visitantes mais freqüentes em flores de Clusia. O comportamento de coleta de recursos florais é descrito.

  8. Reproductive biology of Davilla kunthii A. St-Hil. (Dilleniaceae in Central Amazonia Biologia reprodutiva de Davilla kunthii A. St-Hil. (Dilleniaceae na Amazônia Central

    Directory of Open Access Journals (Sweden)

    André Rodrigo Rech

    2011-06-01

    Full Text Available This survey aimed at describing the interactions of floral visitors and Davilla kunthii A. St.-Hil. as well as characteristics of its reproductive biology in Itacoatiara, state of Amazonas, Brazil. Tests of the breeding system were performed. The guild of visitors was described according to richness, abundance, relative frequency and constancy. The breeding system tests indicated that D. kunthii is self-compatible. The pollination system was characterized as generalist, with 39 visitor species, from three different orders. Bees were the main group of pollinators, thus some behavioural aspects were described. Th e period of highest foraging activity was between 7 and 10 am. Some species presented agonistic and monopolistic behaviour. Given the behaviour and destructive potential, the Curculionidae seem to have a greater impact as seed predators than pollinators.Este trabalho descreve as relações entre visitantes florais e Davilla kunthii A. St.-Hil., bem como características de sua biologia reprodutiva em Itacoatiara (Amazonas. Foram realizados os testes referentes ao estudo do sistema reprodutivo. A guilda de visitantes foi caracterizada quanto à riqueza, abundância, frequência relativa e constância. Os testes para sistema reprodutivo indicaram que D. kunthii possui auto-compatibilidade. O mecanismo de polinização configurou-se como generalista com 39 espécies de visitantes florais, provenientes de três diferentes ordens. Abelhas corresponderam ao principal grupo de polinizadores, desta forma, alguns aspectos comportamentais foram descritos. O horário de maior forrageamento ocorreu entre 7 e 10 horas. Algumas espécies apresentaram interações agonísticas e comportamento monopolizador da fonte de alimento. Dado o comportamento e o potencial destrutivo, embora possa ocasionalmente atuar como polinizadores, Curculionidae parecem possuir maior impacto como predadores de sementes.

  9. Biologia de Centris Fabricius (Hymenoptera, Anthophoridae, Centridini em matas contínuas e fragmentos na Amazônia Central Biology of Centris Fabricius (Hymenoptera, Anthophoridae, Centridini in continuous forest and fragments in Central Amazonia

    Directory of Open Access Journals (Sweden)

    Elder F. Morato

    1999-01-01

    Full Text Available A study of four tree-hole nesting bee species of Centris Fabricius, 1804 was conducted between July, 1988 and June, 1990 in isolated and continuous "terra firme" forests at Manaus region. Nests were obtained from wood trap-nests of different diameters and consisted of a linear series of brood cells. Centris dichrootricha (Moure, 1945 and C. terminata Smith, 1874 were the most abundant species. Centris terminata nested principally in gaps and continuous forest and C. dichrootricha in cleared areas and small fragments of forest. More nests were obtained in trap-nests placed at 8 and 15 m height above ground. Nesting activity was more pronounced in the wet season between August and January. Natural enemies are the beetle Tetraonyx Latreille, 1805 and the bees Coelioxys Latreille, 1809, Mesocheira Lepeletier & Serville, 1825 and Mesoplia Lepeletier, 1841. Nest architecture of Centris spp. are described.

  10. Danos de Conotrachelus dubiae (Coleoptera: curculionidae em frutos de camu-camu (Myrciaria dubia na Amazônia Central Damage of camu-camu (Myrciaria dubia fruits by Conotrachelus dubiae (Coleoptera: curculionidae in Central Amazonia

    Directory of Open Access Journals (Sweden)

    Sidney Alberto do Nascimento Ferreira

    2003-12-01

    Full Text Available No Brasil, a ocorrência de Conotrachelus dubiae O'Brien, 1995 (Coleoptera: Curculionidae em camu-camu [Myrciaria dubia (H.B.K. McVaugh, Myrtaceae] tinha sido constatada somente em populações naturais. Relata-se sua ocorrência em um cultivo experimental, onde se avaliou os danos de C. dubiae em frutos de camu-camu, em diferentes graus de amadurecimento, entre 1999 e 2003. Os danos causados pela larva aumentaram com o amadurecimento dos frutos, havendo maior comprometimento da polpa do fruto (30 a 90% do que das sementes (7%. A incidência desse inseto pode implicar em perdas quantitativas significativas na produção de camu-camu.In Brazil, the occurrence of Conotrachelus dubiae O'Brien, 1995 (Coleoptera: Curculionidae in camu-camu [Myrciaria dubia (H.B.K. McVaugh, Myrtaceae] had only been verified in natural populations. This report describes its occurrence in an experimental cultivation, where damage of camu-camu fruits by C. dubiae at different ripening stages was evaluated between 1999 and 2003. The damage caused by the larva increased with the degree of ripening of the fruits, with greater damage of fruit pulp (30 to 90% than to seeds (7%. The incidence of this insect may cause significant quantitative losses in the camu-camu production.

  11. Acción gubernamental e institucionalismo en la Amazonia brasileña. El conflicto entorno a las infraestructuras hidroeléctricas

    Directory of Open Access Journals (Sweden)

    Josep Pont Vidal

    2010-01-01

    Full Text Available Este escrito es el fruto de la investigación basada en el conflicto social originado por el proyecto de construcción de la hidroeléctrica de Belo Monte en el río Xingu (estado de Pará, Amazonia oriental y del diagnóstico del "Plano de Desarrollo Regional Sostenible de la Región de Xingú". Se parte de un marco analítico conceptual más amplio que combina los postulados de la corriente sociológica del Nuevo Institucionalismo y la teoría de la acción de Jürgen Habermas. A partir del análisis de la acción instrumental y estratégica de los actores políticos, sociales y económicos de esta región caracterizada de periférica, se establecen una serie de variables.

  12. Zebragryllus Desutter-Grandcolas & Cadena-Casteñada, n.gen. a new Gryllinae genus from Eastern and Western Amazonia, South America (Orthoptera, Grylloidea, Gryllidae).

    Science.gov (United States)

    Desutter-Grandcolas, Laure; Cadena-Castañeda, Oscar J; Jaiswara, Ranjana; Anso, Jeremy

    2014-02-24

    We describe a new genus of grylline cricket, Zebragryllus Desutter-Grandcolas & Cadena-Casteñada n. gen., from the Neotropical Region, using characters of morphology and male genitalia; genitalic characters clearly show that Zebragryllus n. gen. is closely related to Anurogryllus Saussure, 1878. Six species are described as new to science, originax">ting from western (Peru, Colombia) and eastern (French Guiana) Amazonia: Zebragryllus fuscus Desutter-Grandcolas, n. sp., Z. guianensis Desutter-Grandcolas, n. sp., Z. intermedius Desutter-Grandcolas, n. sp., Zebragryllus nauta Desutter-Grandcolas, n. sp., Zebragryllus nouragui Desutter-Grandcolas, n. sp., and Zebragryllus wittoto Desutter-Grandcolas and Cadena-Casteñada, n. sp., type species of the genus. They are characterized by their size, coloration (shining black, most often with white patterns of coloration, hence the genus name), and male and female genitalia. The calling songs of Z. guianensis Desutter-Grandcolas, n. sp., Z. intermedius Desutter-Grandcolas, n. sp., Z. nouragui Desutter-Grandcolas, n. sp., and Z. wittoto Desutter-Grandcolas and Cadena-Casteñada, n. sp. are described. An identification key is proposed for both males and females.

  13. Productos del mercado artesanal en la ciudad de Leticia (Amazonia colombiana elaborados con especies de bosques de Mauritia flexuosa L.f.

    Directory of Open Access Journals (Sweden)

    Sandra Lorena Franco Arango

    2015-06-01

    Full Text Available Los productos forestales no maderables (PFNMs han tomado fuerza como alternativa para la conservación de ecosistemas y la generación de ingresos económicos en las poblaciones asociadas. Se presenta un mayor interés sobre los productos que provienen de bosques oligárquicos (poco diversos y con alta densidad relativa, especialmente los dominados por palmas, como por ejemplo los bosques de Mauritia flexuosa (aguajales, cananguchales o buritizales. En el mercado artesanal de Leticia (Amazonia colombiana se identificaron 68 productos provenientes de nueve especies de plantas del canaguchal, teniendo las palmas (Astrocaryum chambira, Euterpe precatoria, M. flexuosa, Oenocarpus bataua y Socratea exorrhiza el mayor potencial comercial. Los productos más frecuentes fueron las mochilas de fibras de A. chambira (chambira y los precios de venta más altos correspondieron a las esculturas de Brosimum rubescens (palo de sangre. No existen estadísticas oficiales de este mercado, ni entes del Estado que regulen y orienten la producción y comercialización de los productos que se extraen del bosque. No obstante, los PFNMs representan una alternativa para diversificar las oportunidades productivas de los pobladores de la región.

  14. Description and phylogenetic relationships of a new genus and two new species of lizards from Brazilian Amazonia, with nomenclatural comments on the taxonomy of Gymnophthalmidae (Reptilia: Squamata).

    Science.gov (United States)

    Colli, Guarino R; Hoogmoed, Marinus S; Cannatella, David C; Cassimiro, José; Gomes, Jerriane Oliveira; Ghellere, José Mário; Gomes, Jerriane Oliveira; Ghellere, José Mário; Nunes, Pedro M Sales; Pellegrino, Kátia C M; Salerno, Patricia; Souza, Sergio Marques De; Rodrigues, Miguel Trefaut

    2015-08-18

    We describe a new genus and two new species of gymnophthalmid lizards based on specimens collected from Brazilian Amazonia, mostly in the "arc of deforestation". The new genus is easily distinguished from other Gymnophthalmidae by having very wide, smooth, and imbricate nuchals, arranged in two longitudinal and 6-10 transverse rows from nape to brachium level, followed by much narrower, strongly keeled, lanceolate, and mucronate scales. It also differs from all other Gymnophthalmidae, except Iphisa, by the presence of two longitudinal rows of ventrals. The new genus differs from Iphisa by having two pairs of enlarged chinshields (one in Iphisa); posterior dorsal scales lanceolate, strongly keeled and not arranged in longitudinal rows (dorsals broad, smooth and forming two longitudinal rows), and lateral scales keeled (smooth). Maximum parsimony, maximum likelihood, and Bayesian phylogenetic analyses based on morphological and molecular data indicate the new species form a clade that is most closely related to Iphisa. We also address several nomenclatural issues and present a revised classification of Gymnophthalmidae.

  15. Diagnóstico actitudinal hacia la conservación ambiental en estudiantes de la Universidad Nacional de la Amazonia Peruana

    Directory of Open Access Journals (Sweden)

    Herman Guimet

    2013-12-01

    Full Text Available Estudio descriptivo no experimental, que tuvo como objetivo principal, encontrar las diferencias en las actitudes hacia la conservación ambiental entre los estudiantes de la Facultad de Ingeniería Química de la Universidad Nacional de la Amazonia Peruana; según el nivel de estudios, sexo, edad cronológica y el lugar de residencia; la población estuvo conformada por 189 estudiantes y se trabajó con una muestra de 111 estudiantes; la técnica utilizada para recolección de datos fue la encuesta, utilizando como instrumento la escala tipo Likert; los resultados mostraron que en la variable nivel de estudios los estudiantes del III nivel ocuparon el primer lugar, mostrando mejores actitudes y último lugar lo ocupó el V nivel; con respecto a la variable sexo, se encontraron diferencias a favor del sexo masculino; en la variable edad cronológica puede decirse que las actitudes de los estudiantes mayores  ocuparon el primer lugar, seguido de los más jóvenes y finalizando con los estudiantes  del grupo intermedio; así mismo se hallaron diferencias actitudinales entre los estudiantes de los cuatro distrito, como lugar de residencia. La variable nivel de estudios, parece no tener un papel distintivo en las actitudes hacia la conservación ambiental.

  16. Repeat-Pass Multi-Temporal Interferometric SAR Coherence Variations with Amazon Floodplain and Lake Habitats

    Science.gov (United States)

    Jung, H.; Alsdorf, D.

    2006-12-01

    Monitoring discharge in the main channels of rivers and upland tributaries as well as storage changes in floodplain lakes is necessary for understanding flooding hazards, methane production, sediment transport, and nutrient exchange. Interferometric processing of synthetic aperture radar (SAR) data may enable hydrologists to detect environmental and ecological changes in hydrological systems over space and time. An aim of our experiments is to characterize interferometric SAR coherence variations that occur in Amazon aquatic habitats. We analyze coherence variations in JERS-1 data at three central Amazon sites; Lake Balbina, the Cabaliana floodplain, and the confluence of the Purus and Amazon rivers. Because radar pulse interactions with inundated vegetation typically follow a double-bounce travel path which returns energy to the antenna, coherence will vary with vegetation type, physical baseline, and temporal baseline. Balbina's vegetation consists mostly of forest and inundated trunks of dead, leafless trees as opposed to Cabaliana and Amazon- Purus (dominated by flooded forests), thus it serves to isolate the vegetation signal. Coherence variations with baselines were determined from 253 interferograms at Balbina, 210 at Calbaliana, and 153 at Purus. The average temporal and perpendicular baselines (mean std.) are 574 394 days and 1708 1159 m at Balbina, 637 435 days and 1381 981 m at Cabaliana, and 587 425 days and 1430 964 m at Purus. Balbina has a stronger coherence than either Cabaliana or Amazon-Purus. With results of Mann-Whitney statistical tests, Balbina has a difference between terre-firme and flooded coherence values plotted with perpendicular baseline but Cabaliana and Amazon-Purus do not show this difference. Balbina has a linearly decreasing trend in coherence plotted with temporal baseline whereas Cabaliana and Amazon-Purus have a steep drop-off, non- linear change. A strong annual periodicity is evident on power spectrums of the coherence values

  17. The importance of hydraulic architecture to the distribution patterns of trees in a central Amazonian forest.

    Science.gov (United States)

    Cosme, Luiza H M; Schietti, Juliana; Costa, Flávia R C; Oliveira, Rafael S

    2017-07-01

    Species distributions and assemblage composition may be the result of trait selection through environmental filters. Here, we ask whether filtering of species at the local scale could be attributed to their hydraulic architectural traits, revealing the basis of hydrological microhabitat partitioning in a Central Amazonian forest. We analyzed the hydraulic characteristics at tissue (anatomical traits, wood specific gravity (WSG)), organ (leaf area, specific leaf area (SLA), leaf area : sapwood area ratio) and whole-plant (height) levels for 28 pairs of congeneric species from 14 genera restricted to either valleys or plateaus of a terra-firme forest in Central Amazonia. On plateaus, species had higher WSG, but lower mean vessel area, mean vessel hydraulic diameter, sapwood area and SLA than in valleys; traits commonly associated with hydraulic safety. Mean vessel hydraulic diameter and mean vessel area increased with height for both habitats, but leaf area and leaf area : sapwood area ratio investments with tree height declined in valley vs plateau species. [Correction added after online publication 29 March 2017: the preceding sentence has been reworded.] Two strategies for either efficiency or safety were detected, based on vessel size or allocation to sapwood. In conclusion, contrasting hydrological conditions act as environmental filters, generating differences in species composition at the local scale. This has important implications for the prediction of species distributions under future climate change scenarios. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  18. Observations of central stars

    International Nuclear Information System (INIS)

    Lutz, J.H.

    1978-01-01

    Difficulties occurring in the observation of central stars of planetary nebulae are reviewed with emphasis on spectral classifications and population types, and temperature determination. Binary and peculiar central stars are discussed. (U.M.G.)

  19. Gangs in Central America

    National Research Council Canada - National Science Library

    Ribando, Clare

    2005-01-01

    ... activities of Central American gangs. Citizens in several Central American countries have identified crime and gang violence among the top issues of popular concern, and Honduras and El Salvador have recently enacted tough anti-gang legislation...

  20. NIDDK Central Repository

    Data.gov (United States)

    U.S. Department of Health & Human Services — The NIDDK Central Repository stores biosamples, genetic and other data collected in designated NIDDK-funded clinical studies. The purpose of the NIDDK Central...

  1. Is banking supervision central to central banking?

    OpenAIRE

    Joe Peek; Eric S. Rosengren; Geoffrey M. B. Tootell

    1997-01-01

    Whether central banks should play an active role in bank supervision and regulation is being debated both in the United States and abroad. While the Bank of England has recently been stripped of its supervisory responsibilities and several proposals in the United States have advocated removing bank supervision from the Federal Reserve System, other countries are considering enhancing central bank involvement in this area. Many of the arguments for and against these proposals hinge on the effe...

  2. Pueblos de tradición nómada de la Amazonia y la Orinoquía: Aprendizajes y proyecciones para afrontar el futuro. Memorias de un encuentro

    OpenAIRE

    2010-01-01

    Recopilación de las memorias del “Encuentro de pueblos de tradición nómada de la Amazonia y la Orinoquía. Aprendizajes y proyecciones para afrontar el futuro, realizado en San José del Guaviare (Departamento del Guaviare, Colombia), los días 2 y 3 de julio de 2009. Dicho Encuentro fue organizado y convocado por la Alcaldía de San José del Guaviare, la Defensoría del Pueblo seccional Guaviare, el Sistema de Naciones Unidas en Colombia, a través de ACNUR, OACNUDH, OCHA y PNUD, y la Universidad ...

  3. Auditoría social en empresa brasileña transnacional del sector pecuario que actúa en Amazonia legal. (Axe II, Symposium 5) : Estudio de caso.

    OpenAIRE

    De Menezes Costa, Gislane; De L. Pinel, Maria,

    2010-01-01

    La ganadería es una actividad que utiliza gran cantidad de recursos escasos, ocupa mayor extensión de tierras en el mundo y contribuye considerablemente para el aumento del calentamiento global. Brasil, posee el mayor rebaño comercial del mundo, la crianza de ganado, se desloca cada vez más para la Amazonía Legal, generando deforestación además de profundos impactos ambientales y laborales. La opción por la empresa AmaOzonio, que actua en el sector frigorífico en Amazonia Legal, se justifica,...

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

    Science.gov (United States)

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

    1995-12-01

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

  5. Influence of Superparameterization and a Higher-Order Turbulence Closure on Rainfall Bias Over Amazonia in Community Atmosphere Model Version 5: How Parameterization Changes Rainfall

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Kai [Jackson School of Geosciences, University of Texas at Austin, Austin TX USA; Fu, Rong [Jackson School of Geosciences, University of Texas at Austin, Austin TX USA; Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles CA USA; Shaikh, Muhammad J. [Jackson School of Geosciences, University of Texas at Austin, Austin TX USA; Ghan, Steven [Pacific Northwest National Laboratory, Richland WA USA; Wang, Minghuai [Institute for Climate and Global Change Research and School of Atmospheric Sciences, Nanjing University, Nanjing China; Collaborative Innovation Center of Climate Change, Nanjing China; Leung, L. Ruby [Pacific Northwest National Laboratory, Richland WA USA; Dickinson, Robert E. [Jackson School of Geosciences, University of Texas at Austin, Austin TX USA; Marengo, Jose [Centro Nacional de Monitoramento e Alertas aos Desastres Naturais, São Jose dos Campos Brazil

    2017-09-21

    We evaluate the Community Atmosphere Model Version 5 (CAM5) with a higher-order turbulence closure scheme, named Cloud Layers Unified By Binomials (CLUBB), and a Multiscale Modeling Framework (MMF) with two different microphysics configurations to investigate their influences on rainfall simulations over Southern Amazonia. The two different microphysics configurations in MMF are the one-moment cloud microphysics without aerosol treatment (SAM1MOM) and two-moment cloud microphysics coupled with aerosol treatment (SAM2MOM). Results show that both MMF-SAM2MOM and CLUBB effectively reduce the low biases of rainfall, mainly during the wet season. The CLUBB reduces low biases of humidity in the lower troposphere with further reduced shallow clouds. The latter enables more surface solar flux, leading to stronger convection and more rainfall. MMF, especially MMF-SAM2MOM, unstablizes the atmosphere with more moisture and higher atmospheric temperatures in the atmospheric boundary layer, allowing the growth of more extreme convection and further generating more deep convection. MMF-SAM2MOM significantly increases rainfall in the afternoon, but it does not reduce the early bias of the diurnal rainfall peak; LUBB, on the other hand, delays the afternoon peak time and produces more precipitation in the early morning, due to more realistic gradual transition between shallow and deep convection. MMF appears to be able to realistically capture the observed increase of relative humidity prior to deep convection, especially with its two-moment configuration. In contrast, in CAM5 and CAM5 with CLUBB, occurrence of deep convection in these models appears to be a result of stronger heating rather than higher relative humidity.

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

    Directory of Open Access Journals (Sweden)

    Cardona Gladys

    2008-12-01

    Full Text Available

    Capsicum sp. es una especie nativa de América de gran importancia por su diversidad de usos. La Amazonia colombiana es considerada uno de los centros de origen y alberga una gran riqueza de morfoespecies. A pesar de su importancia para el crecimiento y supervivencia de plantas bajo condiciones limitantes de nutrientes, son escasos los trabajos relacionados con la dinámica de los hongos formadores de micorriza arbuscular (HFMA en Capsicum. Se estudió la ocurrencia de HFMA, a partir de colecta de rizósferas y raíces de ají en diferentes rutas. La colonización se evaluó por medio de la metodología de Phillips y Hayman (1970, con modificaciones de Sieverding (1983. El aislamiento y cuantificación de esporas por la técnica de Gerdeman y Nicolson (1963, modificada por Sieverding (1983. La asignación de géneros se realizó a partir de la descripción morfológica de esporas. Todas las plántulas de ají muestreadas presentaron asociaciones con HFMA. Características químicas del suelo, presencia de otras especies vegetales en chagras, fuente de colecta y especies del género Capsicum incidieron en una alta o baja alta ocurrencia de la simbiosis micorrícica. Se identificaron nueve morfotipos de endomicorrizas; Glomus sp. fue el de mayor ocurrencia.

  7. Los pueblos indígenas de la Amazonia Peruana y el uso político de los medios de comunicación

    Directory of Open Access Journals (Sweden)

    Oscar ESPINOSA

    2009-11-01

    Full Text Available RESUMEN: Este artículo trata sobre el uso político de los medios de comunicación (radio, televisión e Internet por parte de los pueblos indígenas de la Amazonia Peruana. En particular, analiza la utilización que el pueblo Shipibo ha hecho de la radio en el proceso de construcción de su identidad étnica y en la creación de sus organizaciones políticas representativas; el tipo de vinculación de los pueblos Ashaninka y Aguaruna, el estado y la televisión sobre todo en la redefinición del concepto de identidad nacional en el contexto de diferentes conflictos armados, y finalmente, se presenta el uso de Internet por el pueblo Ashaninka.El objetivo principal del articulo es mostrar como el empleo de los medios de comunicación permite a las comunidades indígenas hacerse más visibles y actuar políticamente en distintos espacios públicos.ABSTRACT: This article deals with the political use of the means of communication (radio, tv, Internet by the indigenous peoples of the Peruvian Amazonas. In particular, it analyzes the use made by the Shipibo people of the radio in the construction of their ethnic identity and the creation of representative political organization; the links among the Ashaninka and Aguaruna peoples, the state and the tv in the redefinition of the national identity in the context of armed conflicts, and finally, it presents the use of Internet by Ashaninka people.This article aims at showing that the use of mass media allows indigenous groups to become more visible and to act in different political scenarios.

  8. Patrones de distribución de especies arbóreas de dosel y sotobosque a escala local en bosques de tierra firme, Amazonia colombiana

    Directory of Open Access Journals (Sweden)

    Juan Sebastian Barreto-Silva

    2014-03-01

    Full Text Available El efecto de la variación ambiental en la estructura de las comunidades arbóreas en bosques tropicales, aún se debate. En paisajes como los bosques de tierra firme, donde el gradiente ambiental disminuye, el efecto de los suelos sobre los patrones de distribución de especies es mínimo. En contraste, un mayor efecto de la variación edáfica y topográfica sobre la composición florística, se ha reportado en estudios con diferentes tipos de plantas en bosques tropicales. Este estudio se realizó en diez hectáreas de una parcela permanente. Se evaluó el efecto de la variación ambiental y la configuración espacial sobre los patrones florísticos de las especies arbóreas a escala local, según el estado de desarrollo y categorías de abundancia relativa. Se registraron 14 074 individuos de 1 053 especies y 80 familias. Los suelos son ácidos, presentan altas concentraciones de Aluminio y son predominantemente arcillosos. La diversidad beta fue baja. Las diferencias florísticas explicadas fueron asociadas con procesos biológicos espacialmente estructurados, particularmente, con la limitación en dispersión. Aunque, la mayor parte de la variación no fue explicada por las variables consideradas. Estos resultados sugieren que procesos aleatorios son determinantes esenciales de la variación florística en bosques de tierra firme de la amazonia.

  9. Local perceptions as a guide for the sustainable management of natural resources: empirical evidence from a small-scale society in Bolivian Amazonia

    Directory of Open Access Journals (Sweden)

    Álvaro Fernández-Llamazares

    2016-03-01

    Full Text Available Research on natural resource management suggests that local perceptions form the basis upon which many small-scale societies monitor availability and change in the stock of common-pool natural resources. In contrast, this literature debates whether local perceptions can be effective in guiding the sustainable management of natural resources. With empirical evidence on this matter still highly limited, we explored the role of local perceptions as drivers of harvesting and management behavior in a small-scale society in Bolivian Amazonia. We conducted structured interviews to capture local perceptions of availability and change in the stock of thatch palm (Geonoma deversa among the Tsimane', an indigenous society of foragers-horticulturalists (n = 296 adults in 13 villages. We analyzed whether perceptions of availability match estimates of abundance obtained from ecological data and whether differences in perception help to explain harvesting behavior and local management of thatch palm. Perceptions of availability of G. deversa are highly contingent upon the social, economic, and cultural conditions within which the Tsimane' have experienced changes in the availability of the resource, thus giving a better reflection of the historical, rather than of the ecological, dimensions of the changes undergone. Although local perceptions might fall short in precision when scrutinized from an ecological standpoint, their importance in informing sustainable management should not be underestimated. Our findings show that most of the harvesting and management actions that the Tsimane' undertake are, at least partially, shaped by their local perceptions. This paper contributes to the broader literature on natural resource management by providing empirical evidence of the critical role of local perceptions in promoting collective responses for the sustainable management of natural resources.

  10. Central Laboratories Services

    Data.gov (United States)

    Federal Laboratory Consortium — The TVA Central Laboratories Services is a comprehensive technical support center, offering you a complete range of scientific, engineering, and technical services....

  11. Central Pain Syndrome

    Science.gov (United States)

    ... such as neurontin (gabapentin) can be useful. Lowering stress levels appears to reduce pain. View Full Treatment Information Definition Central pain syndrome is a neurological condition caused ...

  12. Central Diabetes Insipidus, Central Hypothyroidism, Renal Tubular ...

    African Journals Online (AJOL)

    readmitted to the hospital because of jaundice and failure to thrive, for which he was investigated and diagnosed to have central congenital hypothyroidism. Shortly thereafter, he was admitted to our institute with a history of vomiting, decreased oral intake, polyuria, and dehydration having lasted 5 days. He was investigated ...

  13. Optimal Central Bank Transparency

    NARCIS (Netherlands)

    van der Cruijsen, C.A.B.; Eijffinger, S.C.W.; Hoogduin, L.H.

    2008-01-01

    Should central banks increase their degree of transparency any further? We show that there is likely to be an optimal intermediate degree of central bank transparency. Up to this optimum more transparency is desirable: it improves the quality of private sector inflation forecasts. But beyond the

  14. Optimal central bank transparency

    NARCIS (Netherlands)

    van der Cruijsen, C.A.B.; Eijffinger, S.C.W.; Hoogduin, L.

    2008-01-01

    Should central banks increase their degree of transparency any further? We show that there is likely to be an optimal intermediate degree of central bank transparency. Up to this optimum more transparency is desirable: it improves the quality of private sector inflation forecasts. But beyond the

  15. Optimal central bank transparency

    NARCIS (Netherlands)

    van der Cruijsen, C.A.B.; Eijffinger, S.C.W.; Hoogduin, L.H.

    2010-01-01

    Should central banks increase their degree of transparency any further? We show that there is likely to be an optimal intermediate degree of central bank transparency. Up to this optimum more transparency is desirable: it improves the quality of private sector inflation forecasts. But beyond the

  16. Idiopathic central diabetes Insipidus.

    Science.gov (United States)

    Grace, Mary; Balachandran, Venu; Menon, Sooraj

    2011-10-01

    Idiopathic central diabetes insipidus (CDI) is a rare disorder characterized clinically by polyuria and polydipsia, and an abnormal urinary concentration without any identified etiology. We report a case of central diabetes insipidus in a 60-year-old lady in the absence of secondary causes like trauma, infection, and infiltrative disorders of brain.

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

    Science.gov (United States)

    Silva, H P; Padez, C

    2006-01-01

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

  18. Using Riverboat-Mounted Eddy Covariance for Direct Measurements of Air-water Gas Exchange in Amazonia

    Science.gov (United States)

    Miller, S. D.; Freitas, H.; Read, E.; Goulden, M. L.; Rocha, H.

    2007-12-01

    Gas evasion from Amazonian rivers and lakes to the atmosphere has been estimated to play an important role in the regional budget of carbon dioxide (Richey et al., 2002) and the global budget of methane (Melack et al., 2004). These flux estimates were calculated by combining remote sensing estimates of inundation area with water-side concentration gradients and gas transfer rates (piston velocities) estimated primarily from floating chamber measurements (footprint ~1 m2). The uncertainty in these fluxes was large, attributed primarily to uncertainty in the gas exchange parameterization. Direct measurements of the gas exchange coefficient are needed to improve the parameterizations in these environments, and therefore reduce the uncertainty in fluxes. The micrometeorological technique of eddy covariance is attractive since it is a direct measurement of gas exchange that samples over a much larger area than floating chambers, and is amenable to use from a moving platform. We present eddy covariance carbon dioxide exchange measurements made using a small riverboat in rivers and lakes in the central Amazon near Santarem, Para, Brazil. Water-side carbon dioxide concentration was measured in situ, and the gas exchange coefficient was calculated. We found the piston velocity at a site on the Amazon River to be similar to existing ocean-based parameterizations, whereas the piston velocity at a site on the Tapajos River was roughly a factor 5 higher. We hypothesize that the enhanced gas exchange at the Tapajos site was due to a shallow upwind fetch. Our results demonstrate the feasibility of boat-based eddy covariance on these rivers, and also the utility of a mobile platform to investigate spatial variability of gas exchange.

  19. Central Diffraction in ALICE

    CERN Document Server

    Schicker, R

    2012-01-01

    The ALICE experiment at the Large Hadron Collider (LHC) at CERN consists of a central barrel, a muon spectrometer and of additional detectors for trigger and event classification purposes. The low transverse momentum threshold of the central barrel gives ALICE a unique opportunity to study the low mass sector of central production at the LHC. I will report on first analysis results of meson production in double gap events in minimum-bias proton-proton collisions at sqrt{s} = 7 TeV, and will describe a dedicated double gap trigger for future data taking.

  20. Inferences of Present and Past Changes at Isolated Enclaves and Matrix of Savannas by Carbon Isotopes in a Transitional Forest-Savanna Area in Northern Amazonia

    Science.gov (United States)

    Couto-Santos, F. R.; Luizao, F. J.; Camargo, P. B.

    2013-12-01

    The evolutionary history of savannas influenced by short term climate cycles, during the Quaternary Period, could prompt variations in forest cover often related to movements of the forest-savanna boundary. In this study we investigated current and past changes in the structure of vegetation and the origins of savannas of different natures in a biogeographically and climatic transitional forest-savanna area in northern Amazonia. Variations in the isotopic composition of soil organic matter (δ13C) from surface soils (0-10 cm) along forest-savanna boundaries, detected by a sigmoidal non-linear function, were used to identify current changes in vegetation, while past changes were inferred by discontinuities in the evolution of δ13C with soil depth using piecewise regression associated with radiocarbon dating (14C). By comparing small isolated savanna enclaves inside a strictly protected nature reserve (ESEC Maracá) with its outskirts unprotected continuous savanna matrix, we found that origins and the patterns of dynamics were distinct between these areas and did not respond in the same way to climate change and fire events, either in the last decades or during the Holocene. The stability of the present boundaries of the surrounding savanna matrix reflects the resilience of the transitional forests under a recent intensified fire regime and favorable climate, while the deep forest soil isotopic signal indicated a forest shrinkage of at least 70 m occurring since its origin in early Holocene until 780 years BP associated with a climate drier than the current one. Contrarily, the protected enclaves inside ESEC Maracá, remained stable since the middle Holocene, suggesting a non-anthropogenic origin related to soil edaphic conditions, but with recent dynamics of advancing forest by 8 m century-1 favored by current climate and lacking fire events. A detailed understanding of the origins of savannas of distinct natures and the way they are affected by climate and fire

  1. Rainfall partitioning and related hydrochemical fluxes in a diverse and in a mono specific (Phenakospermum guyannense) secondary vegetation stand in eastern Amazonia.

    Science.gov (United States)

    Hölscher, D; Sá, T D A; Möller, R F; Denich, M; Fölster, H

    1998-04-01

    Rainfall partitioning into throughfall and stemflow was studied in a diverse and in a mono specific stand of secondary vegetation in Eastern Amazonia. The nutrient concentrations in the water were analysed in order to quantify the related hydrochemical fluxes. Secondary vegetation forms the fallow in the local shifting cultivation system and is usually dominated by shrubs and trees. Phenakospermum guyannense (Strelitziaceae), a banana-like herb, is one of the predominant non-woody species. The study was conducted during an 18-month period in a 2.5-year-old relatively species-rich stand and a 10-year-old stand dominated by P. guyannense. In a year with 1956 mm of rainfall 65% (1281 mm) of this quantity reached the soil as throughfall in the diverse stand and 38% (743 mm) in the mono specific stand. Stemflow was estimated to be 23% and 41% respectively. P. guyannense and Banara guianensis (Flacourtiaceae), a tree species, were causing these high funnelling effects. In the young diverse stand B. guianensis had a stemflow of more than 200 l year -1 and P. guyannense had a median flux of 77 l year -1 per pseudostem. In the older stand the taller plants of P.␣guyannense collected 644 l year -1 per pseudostem on the median. The reason for these high values could be the banana-like growth form of P. guyannense and the crown morphology of B. guianensis, which has inclined branches. The low proportion of throughfall and the high stemflow values differ from all previous studies in Amazonian primary forests. The proximity to the Atlantic Ocean strongly influenced the nutrient fluxes via rainfall at our study site. This becomes obvious from the high Na and Cl fluxes with rainfall (19.7 kg Na ha -1 year -1 , 37.2 kg Cl ha -1 year -1 ) which were approximately equal to the Na and Cl fluxes with the sum of throughfall and stemflow for both stands. K fluxes in throughfall and stemflow in both stands were higher than in rainfall by a factor of 8. The high K

  2. Remote Sensing of Leaf Area Index from LiDAR Height Percentile Metrics and Comparison with MODIS Product in a Selectively Logged Tropical Forest Area in Eastern Amazonia

    Directory of Open Access Journals (Sweden)

    Yonghua Qu

    2018-06-01

    Full Text Available Leaf area index (LAI is an important parameter to describe the capacity of forests to intercept light and thus affects the microclimate and photosynthetic capacity of canopies. In general, tropical forests have a higher leaf area index and it is a challenge to estimate LAI in a forest with a very dense canopy. In this study, it is assumed that the traditional Light Detection and Ranging (LiDAR-derived fractional vegetation cover (fCover has weak relationship with leaf area index in a dense forest. We propose a partial least squares (PLS regression model using the height percentile metrics derived from airborne LiDAR data to estimate the LAI of a dense forest. Ground inventory and airborne LiDAR data collected in a selectively logged tropical forest area in Eastern Amazonia are used to map LAI from the plot level to the landscape scale. The results indicate that the fCover, derived from the first return or the last return, has no significant correlations with the ground-based LAI. The PLS model evaluated by the leave-one-out validation shows that the estimated LAI is significantly correlated with the ground-based LAI with an R2 of 0.58 and a root mean square error (RMSE of 1.13. A data comparison indicates that the Moderate Resolution Imaging Spectrometer (MODIS LAI underestimates the landscape-level LAI by about 22%. The MODIS quality control data show that in the selected tile, the cloud state is not the primary factor affecting the MODIS LAI performance; rather, the LAI from the main radiative transfer (RT algorithm contributes much to the underestimation of the LAI in the tropical forest. In addition, the results show that the LiDAR-based LAI has a better response to the logging activities than the MODIS-based LAI, and that the leaf area reduction caused by logging is about 13%. In contrast, the MODIS-based LAI exhibits no apparent spatial correlation with the LiDAR-based LAI. It is suggested that the main algorithm of MODIS should be

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

    Science.gov (United States)

    Santos, G. L. P.

    2015-12-01

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

  4. "Central Station" Londonis

    Index Scriptorium Estoniae

    2000-01-01

    Londoni galeriis Milch seitsme läti, leedu ja eesti kunstniku projekt "Central Station". Kuraatorid Lisa Panting, Sally Tallant. Eestist osalevad Hanno Soans (Catarina Campinoga koostöös valminud video), Kiwa, Kai Kaljo

  5. The central noradrenergic system

    African Journals Online (AJOL)

    2006-07-27

    Jul 27, 2006 ... recognition of a direct influence of the central noradrenergic system on peripheral ... influences on cerebral function and behavior it is impossible to imagine ... stimuli and to speed-up information processing.4. The influence of ...

  6. Central Asian Republic Info

    Data.gov (United States)

    US Agency for International Development — CAR Info is designed and managed by the Central Asian Republic Mission to fill in the knowledge and reporting gaps in existing agency systems for that Mission. It...

  7. Outsourcing central banking

    DEFF Research Database (Denmark)

    Khoury, Sarkis Joseph; Wihlborg, Clas

    2005-01-01

    The literature on Currency Boards (CB) stops at the water edge in terms of dealing with the totality of the functions of a central bank. Monetary policy, and banking supervisioncan be "outsourced" in an open economy with substantial foreign direct investment (FDI)in the banking sector if political...... nationalism does not trump economic rationality. An orthodox CB renders the central banking function redundant in terms of interest rate and exchange rate determination. FDI in banking could perform the same role for the supervisory function of central banks. We use the case of Estonia to illustrate...... the feasibility of, and constraints on, outsourcing of central bank functions. A brief discussion of the Argentinian experience is used for contrast.Key words: Currency Board, Foreign Banks, Supervision, Regional Integration,outsourcing....

  8. Central nervous system resuscitation

    DEFF Research Database (Denmark)

    McIntosh, T K; Garde, E; Saatman, K E

    1997-01-01

    Traumatic injury to the central nervous system induces delayed neuronal death, which may be mediated by acute and chronic neurochemical changes. Experimental identification of these injury mechanisms and elucidation of the neurochemical cascade following trauma may provide enhanced opportunities...

  9. Central nervous system

    Science.gov (United States)

    The central nervous system is composed of the brain and spinal cord. Your brain and spinal cord serve as the main "processing center" for your entire nervous system. They control all the workings of your body.

  10. Central Pontine Myelinolysis

    Science.gov (United States)

    ... Clinical Trials Organizations Publications Definition Central pontine myelinolysis (CPM) is a neurological disorder that most frequently occurs ... Experts estimate that 10 percent of those with CPM will also have areas of EPM. The initial ...

  11. Central banks: Paradise lost

    OpenAIRE

    Issing, Otmar

    2012-01-01

    The focus of the paper is to analyze how the concept behind central bank policy developed over time and how the recent financial crisis and its consequences will have an influence. While the principles of the institutional arrangement for central banks (independence, clear mandate, prohibition of monetary financing) are relevant as ever, pre- crisis consensus strategies of monetary policy have been revealed as flawed. The close monitoring of money and credit developments, a key lesson to be d...

  12. Global warming in Amazonia: impacts and Mitigation Aquecimento Global na Amazônia: impactos e Mitigação

    Directory of Open Access Journals (Sweden)

    Philip Martin Fearnside

    2009-01-01

    Full Text Available Global warming has potentially catastrophic impacts in Amazonia, while at the same time maintenance of the Amazon forest offers one of the most valuable and cost-effective options for mitigating climate change. We know that the El Niño phenomenon, caused by temperature oscillations of surface water in the Pacific, has serious impacts in Amazonia, causing droughts and forest fires (as in 1997-1998. Temperature oscillations in the Atlantic also provoke severe droughts (as in 2005. We also know that Amazonian trees die both from fires and from water stress under hot, dry conditions. In addition, water recycled through the forest provides rainfall that maintains climatic conditions appropriate for tropical forest, especially in the dry season. What we need to know quickly, through intensified research, includes progress in representing El Niño and the Atlantic oscillations in climatic models, representation of biotic feedbacks in models used for decision-making about global warming, and narrowing the range of estimating climate sensitivity to reduce uncertainty about the probability of very severe impacts. Items that need to be negotiated include the definition of "dangerous" climate change, with the corresponding maximum levels of greenhouse gases in the atmosphere. Mitigation of global warming must include maintaining the Amazon forest, which has benefits for combating global warming from two separate roles: cutting the flow the emissions of carbon each year from the rapid pace of deforestation, and avoiding emission of the stock of carbon in the remaining forest that can be released by various ways, including climate change itself. Barriers to rewarding forest maintenance include the need for financial rewards for both of these roles. Other needs are for continued reduction of uncertainty regarding emissions and deforestation processes, as well as agreement on the basis of carbon accounting. As one of the countries most subject to impacts of

  13. Variación florística de especies arbóreas a escala local en un bosque de tierra firme en la Amazonia colombiana Floristic variation of canopy tree species at a local scale on tierra firme forests in colombian Amazonia

    Directory of Open Access Journals (Sweden)

    Juan Sebastian Barreto Silva

    2010-03-01

    Full Text Available El presente estudio se llevó a cabo en cinco hectáreas de una parcela permanente establecida en el Parque Nacional Amacayacu, Amazonia colombiana. En éste, se evaluó el efecto de la variación ambiental y la configuración espacial sobre los patrones florísticos de las especies arbóreas (DAP>10 cm a escala local en un bosque de tierra firme. Se estudió la variación florística y ambiental en cuadrantes de 20x20 m. Adicionalmente, se consideraron diferentes categorías de abundancia (total, alta, media y baja. Se utilizó el Análisis de Correspondencia Linealizado y el Análisis de Correspondencia Canónica, seguido de una partición de la variación, para cuantificar la magnitud a la cual el ambiente y la limitación en dispersión determinan la variación florística. La fracción espacial, representando procesos de autocorrelación como la limitación en dispersión, se analizó mediante dos métodos: Asumiendo un polinomio de tercer grado y por el método de Coordenadas Principales de Matrices Vecinas (PCNM. La diversidad beta de la parcela fue baja. El PCNM aparece como el método de análisis más apropiado para estudios a esta escala. Las diferencias florísticas explicadas a lo largo de la parcela de 5-ha fueron principalmente asociadas con procesos biológicos como la limitación en dispersión. La mayor parte de la variación florística, no obstante, no fue explicada por las variables ambientales o espaciales consideradas. En conclusión, estos resultados sugieren que procesos aleatorios son determinantes esenciales de la variación espacial de las especies arbóreas a escala local en tierra firme en los bosques en el Parque Nacional Amacayacu.This study was carried out in a 5-ha permanent plot established in the Amacayacu National Park, Colombian Amazonia. We assessed the extent at which floristic patterns of tree species were determined by either the environmental variation or the spatial configuration in tierra firme

  14. CENTRAL PLATEAU REMEDIATION

    International Nuclear Information System (INIS)

    ROMINE, L.D.

    2006-01-01

    A systematic approach to closure planning is being implemented at the Hanford Site's Central Plateau to help achieve the goal of closure by the year 2035. The overall objective of Central Plateau remediation is to protect human health and the environment from the significant quantity of contaminated material that resulted from decades of plutonium production in support of the nation's defense. This goal will be achieved either by removing contaminants or placing the residual contaminated materials in a secure configuration that minimizes further migration to the groundwater and reduces the potential for inadvertent intrusion into contaminated sites. The approach to Central Plateau cleanup used three key concepts--closure zones, closure elements, and closure process steps--to create an organized picture of actions required to complete remediation. These actions were merged with logic ties, constraints, and required resources to produce an integrated time-phased schedule and cost profile for Central Plateau closure. Programmatic risks associated with implementation of Central Plateau closure were identified and analyzed. Actions to mitigate the most significant risks are underway while high priority remediation projects continue to make progress

  15. The Naive Central Banker

    Directory of Open Access Journals (Sweden)

    Marcelo de Carvalho Griebeler

    2015-09-01

    Full Text Available There has been in some countries a trend of assigning other functions to central banks besides price stability. The most suggested function to be added to monetary authority’s obligations is to pursue economic growth or full employment. In this paper we characterize the behavior and analyse the optimal monetary policy of, what we call, a naive central banker. We describe the naive behavior as one that does face the inflation-unemployment trade-off, but it tries to minimize both variables simultaneously. Our findings, both under discretion and commitment, indicate that the naive central banker delivers lower expected inflation and inflation variance than the benchmark behavior whenever the economy is rigid enough. However, the degree of conservativeness also affects this result, such that the less conservative the naive policymaker, the more rigidity is necessary.

  16. Colloquium on Central Asia

    International Nuclear Information System (INIS)

    2005-01-01

    This colloquium on Azerbaijan was organized by the direction of international relations of the French Senate and the French center of foreign trade (CFCE). This document gathers the interventions of the participants and the debates with the audience following these interventions. The topics treated concern: - the present day political-economical situation of Central Asia countries (problem of borders, relations with Russia and China); - the economies of Central Asia countries: short term problems and medium-term perspectives; - the relations with the European Union (political, economical, trade and investments, perspectives); - the European energy stakes of Caspian sea (oil and gas reserves, development of hydrocarbon resources, exploitation and transport constraints, stakes for Europe and France); - TotalFinaElf company in Central Asia (Kazakhstan, Azerbaijan, enclavement problem); - the economical impacts of the TRACECA pathway (Transport Corridor Europe Caucasus Asia). (J.S.)

  17. Central Station Design Options

    DEFF Research Database (Denmark)

    2011-01-01

    . The work identifies the architecture, sizing and siting of prospective Central Stations in Denmark, which can be located at shopping centers, large car parking lots or gas stations. Central Stations are planned to be integrated in the Danish distribution grid. The Danish island of Bornholm, where a high...... overloading, more reference points might be necessary to represent various transformer loading levels. The subject of safety in Central Station is also addressed. A number of safety rules based on European standards apply to AC charging equipment up to 44 kW. The connection interlock and the automatic de......-energization are identified as fundamental requirements for safety in such a charging station. The connection interlock is a solution which ensures that no power is applied to the DC cable when the EV connector is not connected. The automatic de-energization device ensures that whenever a strain on the cable is detected, e...

  18. The central nervous system

    International Nuclear Information System (INIS)

    Holmes, R.A.

    1984-01-01

    The first section presents a comprehensive evaluation of radionuclide imaging of the central nervous system and provides a comparison of the detection accuracies of radionuclide imaging (RNI) and XCT in certain lesions, realizing that the XCT results may vary when radiocontrast or newer generation XCT scanners are used. Although conventional radionuclide imaging of the central nervous system has experienced no significant changes over the last 7 years except for mild refinements, a new section has been added on positron emission tomography (PET). Most positron radiopharmaceuticals passively cross the intact blood-brain barrier, and their localization has catalyzed renewed interest in our ability to metabolically study and obtain images of the central nervous system. The section on radionuclide cisternography has been rewritten to reflect present day practice and the wider application of XCT in describing conditions affecting the ventricular system

  19. Potential for seed bank formation of two weed species from Brazilian Amazonia Potencial para a formação de banco de sementes de duas espécies de plantas daninhas da Amazônia brasileira

    Directory of Open Access Journals (Sweden)

    Moacyr B. Dias-Filho

    1999-08-01

    Full Text Available The potential for seed bank formation of two perennial weed species, Ipomoea asarifolia (Desr. Roem. & Schult. (Convolvulaceae and Stachytarpheta cayennensis (Rich. M. Vahl (Verbenaceae, both common in Amazonia , was evaluated in a degraded pasture area in eastern Brazilian Amazonia . Seeds were enclosed in nylon mesh packets and placed at the soil surface or buried at 5 or 10 cm deep. The number of viable seeds was recorded at 6, 10, 14 and 18 months after burial. Results showed that S. cayennensis has the ability to form persistent soil seed bank, while I. asarifolia seeds do not build up in the soil seed bank. For S. cayennensis and, to some extent, for I. asarifolia, seed survival was highest at greater burial depths.O potencial para a formação de banco de sementes de duas espécies perenes de plantas daninhas, Ipomoea asarifolia (Desr. Roem. & Schult. (Convolvulaceae e Stachytarpheta cayennensis (Rich. M. Vahl (Verbenaceae, ambas comuns na Amazônia, foi avaliado em uma área de pastagem degradada na Amazônia oriental brasileira. As sementes foram inseridas em envelopes de tela de nylon e colocadas na superfície do solo ou enterradas a cinco ou 10 cm de profundidade. O número de sementes viáveis foi avaliado aos 6, 12, 14 e 18 meses após o início do ensaio. Os resultados mostraram que S. cayennensis tem o potencial para formar banco de sementes persistente, enquanto que as sementes de I. asarifolia não apresentam esse potencial. Em S. cayennensis e, de certo modo, em I. asarifolia, a sobrevivência de sementes foi maior nas maiores profundidades.

  20. Atmospheres of central stars

    International Nuclear Information System (INIS)

    Hummer, D.G.

    1978-01-01

    The author presents a brief summary of atmospheric models that are of possible relevance to the central stars of planetary nebulae, and then discusses the extent to which these models accord with the observations of both nebulae and central stars. Particular attention is given to the significance of the very high Zanstra temperature implied by the nebulae He II lambda 4686 A line, and to the discrepancy between the Zanstra He II temperature and the considerably lower temperatures suggested by the appearance of the visual spectrum for some of these objects. (Auth.)

  1. Central Bank independence

    Directory of Open Access Journals (Sweden)

    Vasile DEDU

    2012-08-01

    Full Text Available In this paper we present the key aspects regarding central bank’s independence. Most economists consider that the factor which positively influences the efficiency of monetary policy measures is the high independence of the central bank. We determined that the National Bank of Romania (NBR has a high degree of independence. NBR has both goal and instrument independence. We also consider that the hike of NBR’s independence played an important role in the significant disinflation process, as headline inflation dropped inside the targeted band of 3% ± 1 percentage point recently.

  2. Several Centuries of Centrality

    OpenAIRE

    Dana L. Roth

    2015-01-01

    As Carolyn Bertozzi mentioned in her inaugural editorial, the relationship of “Central Science” to “Chemistry” became popularized over 40 years ago with the publication of the first edition of Brown and LeMay’s Chemistry: The Central Science, now in its 13th edition. Yet as late as 2003, Prof. Sason Shaik at The Hebrew University claimed “popularization of chemistry remains scant.” He goes on to share [his] “own experience of popularizing chemistry by delivering the following universal messag...

  3. Central Venous Access

    International Nuclear Information System (INIS)

    Ganeshan, Arul; Warakaulle, Dinuke R.; Uberoi, Raman

    2007-01-01

    Central venous access plays an important role in the management of an ever-increasing population of patients ranging from those that are critically ill to patients with difficult clinical access. Interventional radiologists are key in delivering this service and should be familiar with the wide range of techniques and catheters now available to them. A comprehensive description of these catheters with regard to indications, technical aspects of catheterization, success rates, and associated early and late complications, as well as a review of various published guidelines on central venous catheter insertion are given in this article

  4. Centralized mouse repositories.

    Science.gov (United States)

    Donahue, Leah Rae; Hrabe de Angelis, Martin; Hagn, Michael; Franklin, Craig; Lloyd, K C Kent; Magnuson, Terry; McKerlie, Colin; Nakagata, Naomi; Obata, Yuichi; Read, Stuart; Wurst, Wolfgang; Hörlein, Andreas; Davisson, Muriel T

    2012-10-01

    Because the mouse is used so widely for biomedical research and the number of mouse models being generated is increasing rapidly, centralized repositories are essential if the valuable mouse strains and models that have been developed are to be securely preserved and fully exploited. Ensuring the ongoing availability of these mouse strains preserves the investment made in creating and characterizing them and creates a global resource of enormous value. The establishment of centralized mouse repositories around the world for distributing and archiving these resources has provided critical access to and preservation of these strains. This article describes the common and specialized activities provided by major mouse repositories around the world.

  5. Effects of dam-induced landscape fragmentation on amazonian ant-plant mutualistic networks.

    Science.gov (United States)

    Emer, Carine; Venticinque, Eduardo Martins; Fonseca, Carlos Roberto

    2013-08-01

    Mutualistic networks are critical to biological diversity maintenance; however, their structures and functionality may be threatened by a swiftly changing world. In the Amazon, the increasing number of dams poses a large threat to biological diversity because they greatly alter and fragment the surrounding landscape. Tight coevolutionary interactions typical of tropical forests, such as the ant-myrmecophyte mutualism, where the myrmecophyte plants provide domatia nesting space to their symbiotic ants, may be jeopardized by the landscape changes caused by dams. We analyzed 31 ant-myrmecophyte mutualistic networks in undisturbed and disturbed sites surrounding Balbina, the largest Central Amazonian dam. We tested how ant-myrmecophyte networks differ among dam-induced islands, lake edges, and undisturbed forests in terms of species richness, composition, structure, and robustness (number of species remaining in the network after partner extinctions). We also tested how landscape configuration in terms of area, isolation, shape, and neighborhood alters the structure of the ant-myrmecophyte networks on islands. Ant-myrmecophytic networks were highly compartmentalized in undisturbed forests, and the compartments had few strongly connected mutualistic partners. In contrast, networks at lake edges and on islands were not compartmentalized and were negatively affected by island area and isolation in terms of species richness, density, and composition. Habitat loss and fragmentation led to coextinction cascades that contributed to the elimination of entire ant-plant compartments. Furthermore, many myrmecophytic plants in disturbed sites lost their mutualistic ant partners or were colonized by opportunistic, nonspecialized ants. Robustness of ant-myrmecophyte networks on islands was lower than robustness near lake edges and in undisturbed forest and was particularly susceptible to the extinction of plants. Beyond the immediate habitat loss caused by the building of large dams

  6. Imaginaire acoustique et apprentissage d’une ontologie animiste Acoustic imagination and the learning of an animistic ontologyThe case of the Quechua of Peruvian Amazonia

    Directory of Open Access Journals (Sweden)

    Andréa-Luz Gutierrez Choquevilca

    2010-09-01

    Full Text Available Cet article examine le rôle de l’imitation sonore au sein des pratiques et des représentations de la chasse et de la maladie chez les Quechua d’Amazonie (Pastaza, Pérou. L’analyse se fonde sur un ensemble de récits qui mettent en scène une interaction avec les « maîtres du gibier » dans un contexte ordinaire ou rituel. Partant de la description des techniques de chasse au leurre, l’auteur montre la pertinence d’un mode de communication fondé sur la simulation sonore au sein des interactions contrôlées et incontrôlées avec les entités tutélaires du gibier (récits d’initiation cynégétique ou biographies de rencontre d’esprit. Après avoir montré la cohérence de ce schéma dans la sphère de la praxis cynégétique, l’auteur explore un cas de maladie infantile shinkurana, dans lequel l’usage du « masque sonore » et les mécanismes de « voix citées » jouent un rôle clef dans le processus d’attribution d’une « agentivit�� » aux entités pathogènes. L’article analyse ainsi le phénomène de l’imitation sonore comme une stratégie perceptive et cognitive efficace, massivement mobilisée dans un contexte d’apprentissage et de validation des représentations animistes.This article examines the role of sound imitation in the practice and representation of hunting and sickness among the Quechua of Amazonia (Pastaza, Peru. The analysis is based on a set of stories that presents an interaction with “masters of game” in an ordinary or ritual context. Beginning with a description of lure hunting techniques, the author shows the relevance of a communication mode based on sound simulation in controlled and uncontrolled interactions with entities protective of game (stories of hunting initiation or accounts of spirit encounters. After having demonstrated the consistency of this pattern in the sphere of hunting praxis, the author explores a case of infant sickness shinkurana, in which

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

    Directory of Open Access Journals (Sweden)

    Carlos Machado de Freitas

    2009-06-01

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

  8. Anaplasma marginale infection in cattle from south-western Amazonia Infecção por Anaplasma marginale em bovinos na Amazônia Sul Ocidental, Brasil

    Directory of Open Access Journals (Sweden)

    Luciana Gatto Brito

    2010-03-01

    Full Text Available The present study provides the first epidemiological data regarding infection by Anaplasma marginale in cattle reared in south-western Brazilian Amazonia. One simple procedure was adapted for the extraction of DNA from blood clots collected in seven microregions of Rondônia State and two mesoregions of Acre State. PCR method was used to asses the frequency of A. marginale infections in 4 to12-month-old cattle. The cattle infection was investigated by polymerase chain reaction (PCR using the specific primer "msp5" for A. marginale. The DNA amplifications revealed that the mean frequency of A. marginale infection was 98.6% (1,627/1,650 in samples from Rondonia, and 92.87% (208/225 in samples from Acre. The high frequency of A. marginale infections in 4 to 12-month-old cattle indicate a situation of enzootic stability in the studied areas and are comparable to those detected by immunodiagnosis in different endemic regions in Brazil. The DNA extraction of clotted blood method described here can be used for epidemiological studies on anaplasmosis and other bovine hemoparasites.O presente estudo fornece os primeiros dados epidemiológicos relativos a infecção por Anaplasma marginale em bovinos criados na Amazônia Sul Ocidental brasileira. Foi adaptado um procedimento simples para a extração de DNA a partir de coágulos sanguíneos coletados em sete microrregiões do estado de Rondônia e duas mesoregiões do estado do Acre. A técnica da reação em cadeia da polimerase (PCR foi aplicada para avaliar a freqüência da infecção por A. marginale em bovinos com idade entre 4 e 12 meses. Após a extração do DNA de cada amostra, a infecção nos bovinos foi investigada pela amplificação do gene "msp5" de A. marginale. As técnicas de amplificação do DNA revelaram que a freqüência de infecção por A. marginale foi de 98,6% (1.627/1.650 nas amostras provenientes de Rondônia e de 92,87% (208/225 nas amostras do Acre. A alta freqüência da

  9. Centralized vs. de-centralized multinationals and taxes

    OpenAIRE

    Nielsen, Søren Bo; Raimondos-Møller, Pascalis; Schjelderup, Guttorm

    2005-01-01

    The paper examines how country tax differences affect a multinational enterprise's choice to centralize or de-centralize its decision structure. Within a simple model that emphasizes the multiple conflicting roles of transfer prices in MNEs – here, as a strategic pre-commitment device and a tax manipulation instrument –, we show that (de-)centralized decisions are more profitable when tax differentials are (small) large. Keywords: Centralized vs. de-centralized decisions, taxes, MNEs. ...

  10. Central Dogma Goes Digital.

    Science.gov (United States)

    Lin, Yihan; Elowitz, Michael B

    2016-03-17

    In this issue of Molecular Cell, Tay and colleagues (Albayrak et al., 2016) describe a new technique to digitally quantify the numbers of protein and mRNA in the same mammalian cell, providing a new way to look at the central dogma of molecular biology. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Channeling the Central Dogma.

    Science.gov (United States)

    Calabrese, Ronald L

    2014-05-21

    How do neurons and networks achieve their characteristic electrical activity, regulate this activity homeostatically, and yet show population variability in expression? In this issue of Neuron, O'Leary et al. (2014) address some of these thorny questions in this theoretical analysis that starts with the Central Dogma. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. CMS Central Hadron Calorimeter

    OpenAIRE

    Budd, Howard S.

    2001-01-01

    We present a description of the CMS central hadron calorimeter. We describe the production of the 1996 CMS hadron testbeam module. We show the results of the quality control tests of the testbeam module. We present some results of the 1995 CMS hadron testbeam.

  13. Ecodesign in Central America

    NARCIS (Netherlands)

    Crul, M.R.M.

    2003-01-01

    This PhD thesis describes and analyses the change process started by the Ecodesign project in Central America, executed between 1998 and 2002. The project started using the concept and praxis developed in Europe. Nine ecodesign projects were performed in industry, and ecodesign was introduced to

  14. NCEP Central Operations

    Science.gov (United States)

    ) NCO Organizational Chart NOAA's Weather and Climate Operational Supercomputing System is known as Climate Climate Prediction Climate Archives Weather Safety Storm Ready NOAA Central Library Photo Library NCO's MISSION * Execute the NCEP operational model suite - Create climate, weather, ocean, space and

  15. Central oxygen pipeline failure

    African Journals Online (AJOL)

    surgical intensive care unit (ICU), with two patients on full ventilation and ... uncertainty around the cause of the failure and the restoration, .... soon as its level also falls below three tons. Should ... (properly checked and closed prior to each anaesthetic). ... in use at the time of the central oxygen pipeline failure at Tygerberg.

  16. Central American Climatology

    Science.gov (United States)

    1985-04-01

    Central America, as where mean temperatures are relatively warm throughout the year de- so spite seasonal rainfall changes. 75 Elevation, solar angle...November 1982 Control Hidalgo Anos.1952-1963, Republica de Nicaragua, Ministerio de Formento Y O0.PP, Comision Nacional de Energia . Craig, Richard A., The

  17. Extractive reserves in Brazilian Amazonia

    Energy Technology Data Exchange (ETDEWEB)

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

    1989-06-01

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

  18. Andean settlers rush for Amazonia.

    Science.gov (United States)

    Serra-vega, J

    1990-01-01

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

  19. Desarrollo sostenible de la amazonia

    Directory of Open Access Journals (Sweden)

    Zuluaga Luis

    1991-12-01

    Full Text Available De la CUENCA AMAZONICA que tiene una extensión de 725.014.300 hectáreas, Colombia participa con 5.5% , es decir con 39.875.334 hectáreas. Así mismo dicha área es el 34.90%del total de Colombia y constituye la región natural
    más extensa del país. La Amazonía Colombiana está ubicada en la cabecera de varios de los afluentes más caudalosos del gran río Amazonas, la cuenca hidrográfica más amplia del mundo y por lo tanto, es de interés para la conservación de
    las partes bajas. Geográficamente comprende los Departamentos del Caquetá, Putumayo, Vaupés, Amazonas y la división de aguas de Guaviare y Guainía. La Amazonía intervenida con base el cálculos de 1980, era el 10% del área o sea 3.987.533 hectáreas. Alrededor del 80% de
    la superficie deforestada hasta 1980 en la Amazonía ha sido dedicada a pastizales.

  20. Centrality and Creativity:

    DEFF Research Database (Denmark)

    Andersen, Kristina Vaarst; Lorenzen, Mark

    2009-01-01

    To provide new insights into urban hierarchy, this article brings together one of economic geography’s oldest and most well-established notions with one of its newest and most disputed notions: Christäller’s centrality and Florida’s creative class. Using a novel original database, the article...... compares the distribution of the general population and the creative class across 444 city regions in 8 European countries. It finds that the two groups are both distributed according to the rank-size rule, but exhibit different distinct phases with different slopes. The article argues that the two...... distributions are different because market thresholds for creative services and jobs are lower than thresholds for less specialized services and jobs. The article hence concludes that centrality exerts a strong influence upon urban hierarchies of creativity and that the study of creative urban city hierarchies...

  1. Central American Flying Weather

    Science.gov (United States)

    1985-12-01

    CEILING; VISIBILITY; WIND, PRECIPITATIDNc’--." HAZE, SMOKE, TEMPORALE ; MOUNTAIN WAVE; MILITARY METEOROLOGY. 4k- / ’A. bstract; Asummary of~ing weather...1 The " Temporale " ....................................1 Mountain Waves ......................I...............1 Severe Thunderstorms...charts. The for any part of Central America lies in having: Tactical Pilota.e Chart series , produced by the Df -.nse Mapping Agency, is * A good, basic

  2. The European Central Bank

    OpenAIRE

    Binder, Michael; Wieland, Volker

    2006-01-01

    The establishment of the ECB and with it the launch of the euro has arguably been a unique endeavor in economic history, representing an important experiment in central banking. This note aims to summarize some of the main lessons learned from this experiment and sketch some of the prospects for the ECB. It is written for "The New Palgrave Dictionary of Economics", 2nd edition. JEL Classification: E52, E58

  3. FNAL central email systems

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Jack; Lilianstrom, Al; Pasetes, Ray; Hill, Kevin; /Fermilab

    2004-10-01

    The FNAL Email System is the primary point of entry for email destined for an employee or user at Fermilab. This centrally supported system is designed for reliability and availability. It uses multiple layers of protection to help ensure that: (1) SPAM messages are tagged properly; (2) All mail is inspected for viruses; and (3) Valid mail gets delivered. This system employs numerous redundant subsystems to accomplish these tasks.

  4. Centrally Banked Cryptocurrencies

    OpenAIRE

    Danezis, George; Meiklejohn, Sarah

    2015-01-01

    Current cryptocurrencies, starting with Bitcoin, build a decentralized blockchain-based transaction ledger, maintained through proofs-of-work that also generate a monetary supply. Such decentralization has benefits, such as independence from national political control, but also significant limitations in terms of scalability and computational cost. We introduce RSCoin, a cryptocurrency framework in which central banks maintain complete control over the monetary supply, but rely on a distribut...

  5. Centrally Banked Cryptocurrencies

    OpenAIRE

    Danezis, G.; Meiklejohn, S.

    2016-01-01

    Current cryptocurrencies, starting with Bitcoin, build a decentralized blockchain-based transaction ledger, maintained through proofs-of-work that also serve to generate a monetary supply. Such decentralization has benefits, such as independence from national political control, but also significant limitations in terms of computational costs and scalability. We introduce RSCoin, a cryptocurrency framework in which central banks maintain complete control over the monetary supply, but rely on...

  6. Centralized vs decentralized contests

    OpenAIRE

    Beviá, Carmen; Corchón, Luis C.

    2015-01-01

    We compare two contests, decentralized in which there are several independent contests with non overlapping contestants and centralized in which all contestants fight for a unique prize which is the sum of all prizes in the small contests. We study the relationship between payoffs and efforts between these two contests. The first author acknowledges financial support from ECO2008-04756 (Grupo Consolidado-C), SGR2014-515 and PROMETEO/2013/037. The second author acknowledges financial suppor...

  7. Arbuscular mycorrhizal fungal communities along a pedo-hydrological gradient in a Central Amazonian terra firme forest.

    Science.gov (United States)

    de Oliveira Freitas, Rejane; Buscardo, Erika; Nagy, Laszlo; dos Santos Maciel, Alex Bruno; Carrenho, Rosilaine; Luizão, Regina C C

    2014-01-01

    Little attention has been paid to plant mutualistic interactions in the Amazon rainforest, and the general pattern of occurrence and diversity of arbuscular mycorrhizal fungi (AMF) in these ecosystems is largely unknown. This study investigated AMF communities through their spores in soil in a 'terra firme forest' in Central Amazonia. The contribution played by abiotic factors and plant host species identity in regulating the composition, abundance and diversity of such communities along a topographic gradient with different soils and hydrology was also evaluated. Forty-one spore morphotypes were observed with species belonging to the genera Glomus and Acaulospora, representing 44 % of the total taxa. Soil texture and moisture, together with host identity, were predominant factors responsible for shaping AMF communities along the pedo-hydrological gradient. However, the variability within AMF communities was largely associated with shifts in the relative abundance of spores rather than changes in species composition, confirming that common AMF species are widely distributed in plant communities and all plants recruited into the forest are likely to be exposed to the dominant sporulating AMF species.

  8. Contribution to the geologic evolution from the Eastern part of Central Amazonia Province by Rb-Sr geochronology from the Carajas Mineral Province and the Sao Felix do Xingu region, Para State

    International Nuclear Information System (INIS)

    Pereira, Edilea Dutra.

    1992-01-01

    This work deals with a Rb/Sr geochronological study carried on granitoids and granulites of the Carajas Mineral Province (Rio Maria, Serra dos Gradaus and Serra do Pium regions) and Sao Felix do Xingu regions. The Manelao and Ourilandia granitoids of the Sao Felix do Xingu region are associated with the greenstone terrains of the Tucuma Group, and yield an age of 2749 ± 24 Ma with an initial ratio of 0.07028 ± 19, and 2677 ± 50 Ma with an initial ratio of 0.07016 ± 22, respectively. In the Rio Maria region, an age of 2541 ± 74 Ma with an initial ratio of 0.7104 ± 343 was obtained on the Mata Surrao Granite located near the Marajoara Village. This age confirms an archaean monzogranitic magmatism in this region. In the Gradaus area, the Cumaru Granodiorite give an mineral age of 2577 ± 27 Ma similar to the age obtained by whole rock method. Finally, Rb/Sr ages were obtained from granulitic rocks of the Pium Complex located at the Serra do Pium and near the Catete River. Samples of the Serra do Pium yielded ages of 2325 ± 71 Ma (whole rock) and 1857 ± 48 (minerals). Samples from the Catete River area give a whole rock age of 2018 ± 25 Ma with an initial ratio of 0.7039 ± 25. These data show that the Rb/Sr system in these granulitic rocks suffered changes during the Early Proterozoic times. The geochronological data here obtained confirm promptly an Archaean evolution in the studied regions, besides give rise the discussion about the problem related to the Transamazonian Event inside them. (author). 92 refs., 32 figs., 10 tabs

  9. Centralized versus distributed propulsion

    Science.gov (United States)

    Clark, J. P.

    1982-01-01

    The functions and requirements of auxiliary propulsion systems are reviewed. None of the three major tasks (attitude control, stationkeeping, and shape control) can be performed by a collection of thrusters at a single central location. If a centralized system is defined as a collection of separated clusters, made up of the minimum number of propulsion units, then such a system can provide attitude control and stationkeeping for most vehicles. A distributed propulsion system is characterized by more numerous propulsion units in a regularly distributed arrangement. Various proposed large space systems are reviewed and it is concluded that centralized auxiliary propulsion is best suited to vehicles with a relatively rigid core. These vehicles may carry a number of flexible or movable appendages. A second group, consisting of one or more large flexible flat plates, may need distributed propulsion for shape control. There is a third group, consisting of vehicles built up from multiple shuttle launches, which may be forced into a distributed system because of the need to add additional propulsion units as the vehicles grow. The effects of distributed propulsion on a beam-like structure were examined. The deflection of the structure under both translational and rotational thrusts is shown as a function of the number of equally spaced thrusters. When two thrusters only are used it is shown that location is an important parameter. The possibility of using distributed propulsion to achieve minimum overall system weight is also examined. Finally, an examination of the active damping by distributed propulsion is described.

  10. Solar thermal central receivers

    International Nuclear Information System (INIS)

    Vant-Hull, L.L.

    1993-01-01

    Market issues, environmental impact, and technology issues related to the Solar Central Receiver concept are addressed. The rationale for selection of the preferred configuration and working fluid are presented as the result of a joint utility-industry analysis. A $30 million conversion of Solar One to an external molten salt receiver would provide the intermediate step to a commercial demonstration plant. The first plant in this series could produce electricity at 11.2 cents/kWhr and the seventh at 8.2 cents/kWhr, completely competitive with projected costs of new utility plants in 1992

  11. Central osteosclerosis with trichothiodystrophy

    Energy Technology Data Exchange (ETDEWEB)

    Wakeling, Emma L.; Brady, Angela F. [North West Thames Regional Genetics Service, Kennedy-Galton Centre, Level 8 V, North West London Hospitals NHS Trust, Watford Road, HAI 3UJ, Harrow, Middlesex (United Kingdom); Cruwys, Michele [Department of Paediatrics, Hillingdon Hospital, Hillingdon, Middlesex (United Kingdom); Suri, Mohnish [Clinical Genetics Service, City Hospital, Nottingham (United Kingdom); Aylett, Sarah E. [Neurosciences Unit, Great Ormond Street Hospital for Children NHS Trust, London (United Kingdom); Hall, Christine [Department of Radiology, Great Ormond Street Hospital for Children NHS Trust, London (United Kingdom)

    2004-07-01

    Trichothiodystrophy (TTD) is a rare, autosomal recessive, multisystem disorder associated with defects in nucleotide excision repair. We report a 7-year-old boy with TTD due to mutation in the XPD gene. The patient has classic features of this condition, including brittle, sulphur-deficient hair, ichthyosis, growth retardation and developmental delay. In addition, he has radiological evidence of progressive central osteosclerosis. Although similar radiological findings have previously been reported in a small number of patients, this association is not widely recognised. We review the radiological findings in this and other similar cases and discuss the natural history of these bony changes. (orig.)

  12. Central nervous system tumors

    International Nuclear Information System (INIS)

    Curran, W.J. Jr.

    1991-01-01

    Intrinsic tumors of the central nervous system (CNS) pose a particularly challenging problem to practicing oncologists. These tumors rarely metastasize outside the CNS, yet even histologically benign tumors can be life-threatening due to their local invasiveness and strategic location. The surrounding normal tissues of the nervous system is often incapable of full functional regeneration, therefore prohibiting aggressive attempts to use either complete surgical resection or high doses of irradiation. Despite these limitations, notable achievements have recently been recorded in the management of these tumors

  13. Decentralized central heating

    Energy Technology Data Exchange (ETDEWEB)

    Savic, S.; Hudjera, A.

    1994-08-04

    The decentralized central heating is essentially based on new technical solutions for an independent heating unit, which allows up to 20% collectible energy savings and up to 15% savings in built-in-material. These savings are already made possible by the fact that the elements described under point A are thus eliminated from the classical heating. The thus superfluous made elements are replaced by new technical solutions described under point B - technical problem - and point E - patent claim. The technical solutions described in detail under point B and point E form together a technical unit and are essential parts of the invention protected by the patent. (author)

  14. Central Hypothyroidism in Miniature Schnauzers

    NARCIS (Netherlands)

    Voorbij, Annemarie M W Y; Leegwater, Peter A J; Buijtels, Jenny J C W M; Daminet, Sylvie; Kooistra, Hans S

    2016-01-01

    BACKGROUND: Primary hypothyroidism is a common endocrinopathy in dogs. In contrast, central hypothyroidism is rare in this species. OBJECTIVES: The objective of this article is to describe the occurrence and clinical presentation of central hypothyroidism in Miniature Schnauzers. Additionally, the

  15. Central Banking after the Crisis

    OpenAIRE

    Frederick S. Mishkin

    2013-01-01

    This paper explores where central banking is heading after the recent financial crisis. First it discusses the central bank consensus before the crisis and then outlines the key facts learned from the crisis that require changes in the way central banks conduct their business. Finally, it discusses four main areas in which central banks are altering their policy frameworks: 1) the interaction between monetary and financial stability policies, 2) nonconventional monetary policy, 3) risk manage...

  16. Central ignition scenarios for TFTR

    International Nuclear Information System (INIS)

    Zweben, S.J.; Redi, M.H.; Bateman, G.

    1986-03-01

    The possibility of obtaining ignition in TFTR by means of very centrally peaked density profiles is examined. It is shown that local central alpha heating can be made to exceed local central energy losses (''central ignition'') under global conditions for which Q greater than or equal to 1. Time dependent 1-D transport simulations show that the normal global ignition requirements are substantially relaxed for plasmas with peaked density profiles. 18 refs., 18 figs

  17. The central Iowa project.

    Science.gov (United States)

    Allen, H M

    1994-10-01

    This project developed and tested a population-based survey, the HS Form, to examine health and health care in the Central Iowa community. Data from this new collection of proven sets of items were used to compare competing health plans, doctor offices, hospitals, and to develop preliminary norms of the community's insured, in two areas: system performance and health burden. The results showed that the survey: (1) was both feasible and efficient in delivering a comprehensive and generic assessment of consumers and patients; (2) revealed consistent, noteworthy differences between plans and between providers across both sets of criteria; and (3) indicated that there is substantial room for improvement in Central Iowa's health care delivery system from the public's perspective. Recommendations for next steps include: (1) following through on the June 1993 community forum (held to discuss the project's methods and results with local decision makers); (2) broadening the evaluation design to increase sample representativeness; and (3) implementing a pre/post approach to measure changes in plan and provider performance.

  18. Alpha current flow betweenness centrality

    NARCIS (Netherlands)

    Avrachenkov, K.; Litvak, Nelli; Medyanikov, V.; Sokol, M.

    2013-01-01

    A class of centrality measures called betweenness centralities reflects degree of participation of edges or nodes in communication between different parts of the network. The original shortest-path betweenness centrality is based on counting shortest paths which go through a node or an edge. One of

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-07-01

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

  20. Reflexões sobre água de abastecimento e saúde pública: um estudo de caso na Amazônia brasileira Considerations about water supply and public health: a case study in the Brazilian Amazonia

    Directory of Open Access Journals (Sweden)

    Leandro Luiz Giatti

    2007-04-01

    Full Text Available Embora a Amazônia ostente grandioso patrimônio ambiental e abundância de recursos hídricos, é na região Norte do Brasil, contida neste notável bioma, que se verificam os piores índices de acesso a serviços de saneamento e respectivos indicadores de saúde pública. Por meio de estudo de caso efetuado na cidade de São Gabriel da Cachoeira, localizada à noroeste do Estado do Amazonas, com aproximadamente 18.000 habitantes e substancial parcela de população indígena, verificou-se a complexidade de fatores relacionados ao provimento de água e à melhoria da saúde pública para núcleos urbanos da Amazônia. A ausência de políticas concisas, as peculiaridades ambientais, as dificuldades logísticas e financeiras somam-se a questões socioculturais, a aspectos migratórios e a processo de urbanização desordenada, associada a impactos ambientais. Para melhoria da saúde pública nessas circunstâncias torna-se necessária uma abordagem interdisciplinar, que possibilite a gestão dos recursos hídricos, a implementação de saneamento básico e, não obstante, a promoção de adesão dos habitantes.Even though Amazonia displays magnificent environmental heritage and abundance of water resources, it is exactly in the Brazilian northern region, contained in this remarkable biome, that the worst indices of access to sanitation services and respective public health indicators are found. A case study carried out in the town of São Gabriel da Cachoeira, located to the northwest in the State of Amazonas, with nearly 18,000 inhabitants, a large portion of whom are Indians, revealed a complexity of factors related to water supply and public health improvement for urban centers in Amazonia. Lack of proper policies, environmental peculiarities, logistic and financial difficulties, are added to socio-cultural matters, migratory processes, and unorganized urbanization associated with environmental impacts. In order to improve the public health

  1. Orden monetario y bancos centrales Monetary order and Central Banks

    Directory of Open Access Journals (Sweden)

    Aglietta Michel

    1996-06-01

    Full Text Available Con el enfoque evolucionista e institucionalista de la economía de las convenciones francesa, este trabajo analiza el surgimiento histórico de la banca central y la creación institucional del 'arte de la banca central'. El artículo estudia los modelos formales del orden monetario, la banca libre y la banca central, y analiza los eventos históricos que llevaron a que el Banco de Inglaterra inventara el arte de manejar los bancos centrales en conjunción con el aprendizaje colectivo e institucional que lo hizo posible. Aglietta muestra que la banca central no es una creación del Estado sino una creación institucional endógena al sistema de mercado.With the evolutionist and institutionalist focus of the economics of the French conventions, this paper analyzes the historical rise of the central bank and the institutional creation of the 'art of the central bank'. The article studies formal models of the monetary order, free banking and the central bank, and analyzes the historie events that led to the Bank of England inventing the art of managing the central banks, in conjunction with the collective and institutional learning that made it possible. Aglietta shows that the central bank is not a creation of the State, but rather aninstitutional creation endogenous to the market system.

  2. Adult central nervous system

    International Nuclear Information System (INIS)

    Sutton, M.L.

    1985-01-01

    Historically, the adult central nervous system (CNS) was regarded as relatively immune to the effects of ionising radiation, and the recognition of the CNS as a radio-vulnerable structure occurred later than was the case for many other tissues. Increasingly precise knowledge of the time-dose-volume relationships for CNS tolerance has had two important consequences: (1) it has permitted the avoidance of catastrophic and usually lethal late effects in the brain and spinal cord when these tissues are unavoidably irradiated during the treatment of adjacent non-CNS tumours, and (2) it has encouraged referral for irradiation of certain technically benign lesions which, although compatible with prolonged survival, represent a continuing threat to the patient - for example arteriovenous malformations, pituitary adenomas, and some meningiomas. Many of these can now be controlled for very long periods following radiation doses consistent with the long-term functional integrity of the CNS

  3. UA2 central calorimeter

    CERN Multimedia

    The UA2 central calorimeter measured the energy of individual particles created in proton-antiproton collisions. Accurate calibration allowed the W and Z masses to be measured with a precision of about 1%. The calorimeter had 24 slices like this one, each weighing 4 tons. The slices were arranged like orange segments around the collision point. Incoming particles produced showers of secondary particles in the layers of heavy material. These showers passed through the layers of plastic scintillator, generating light which was taken by light guides (green) to the data collection electronics. The amount of light was proportional to the energy of the original particle. The inner 23 cm of lead and plastic sandwiches measured electrons and photons; the outer 80 cm of iron and plastic sandwiches measured strongly interacting hadrons. The detector was calibrated by injecting light through optical fibres or by placing a radioactive source in the tube on the bottom edge.

  4. CENTRAL EUROPE: Austron

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    For many of the countries of Central and Eastern Europe access to international research centres such as CERN, the European Space Agency (ESA), the Institut Laue-Langevin (ILL) or to national centres such as the Rutherford Appleton Laboratory in the UK or DESY in Germany, is hindered by the absence of intermediate research institutions. Since mid-1990 this question has been studied by an 'Austron' Study Group set up under the auspices of the Austrian Academy of Sciences and which cooperates with the so-called 'Pentagonal' initiative of Austria, Czechoslovakia, Hungary, Italy and Yugoslavia to promote cooperation in the area, with which Poland is now associated

  5. Central Accountability System (CLAS)

    International Nuclear Information System (INIS)

    Hairston, L.A.

    1991-01-01

    The Central Accountability System (CLAS) is a high level accountability system that consolidates data from the site's 39 material balance areas (MBA) for reporting to Westinghouse Savannah River Company (WSRC) management, Department of Energy (DOE) and the Nuclear Materials Management and Safeguards System (NMMSS) in Oak Ridge, TN. Development of the system began in 1989 and became operational in April, 1991. The CLAS system enhances data accuracy and accountability records, resulting in increased productivity and time and cost savings. This paper reports that the system is in compliance with DOE Orders and meets NMMSS reporting requirements. WSRC management is provided with the overall status of the site's nuclear material inventory. CLAS gives WSRC a leading edge in accounting technology and enhances good accounting practices

  6. Central America's shrinking forests.

    Science.gov (United States)

    1992-01-01

    This news brief reports that 66% of deforestation in Central America has happened in the past 40 years, based on World Conservation Union (WCU) data. Deforestation is expected to continue. The population of Central America and Mexico grew by 28% between 1977 and 1987. Growth is decreasing but remains high at 2.5% in all countries of the region except Panama. 29 million was the regional population in 1990; the projection is for 63 million by 2025. Population is migrating to urban centers. Forests declined by 13% and croplands increased from 4% to 13% of total land area and pasture land from 2% to 37%. There was an increase in unproductive land from 145 to 24%, i.e., 50% of El Salvador's land had soil degradation as does 30% of Guatemala's. In addition to deforestation and soil degradation, there has been soil erosion leading to sedimentation buildup near dam sites and in rivers, which diminishes hydroelectric power capability. Silting also affects groundwater resources, which impact on a safe drinking water supply. Population growth results in increased demand for fuelwood, urban land, and agricultural land. New techniques practiced widely are needed in order to meet the region's needs or demands. Slowing population growth buys time for adjusting to the necessary changes needed for sustaining the region's population. WCU urges conservation organizations to raise awareness about the role population plays in environmental degradation, and to support efforts to reduce birth rates. Women's status needs to be improved through income-generating projects, for instance, and cooperation is needed between conservation groups and organizations involved with improving maternal and child health.

  7. Central control of thermogenesis.

    Science.gov (United States)

    Clapham, John C

    2012-07-01

    In mammals and birds, conservation of body heat at around 37 °C is vital to life. Thermogenesis is the production of this heat which can be obligatory, as in basal metabolic rate, or it can be facultative such as the response to cold. A complex regulatory system has evolved which senses environmental or core temperature and integrates this information in hypothalamic regions such as the preoptic area and dorsomedial hypothalamus. These areas then send the appropriate signals to generate and conserve heat (or dissipate it). In this review, the importance of the sympathetic nervous system is discussed in relation to its role in basal metabolic rate and adaptive thermogenesis with a particular emphasis to human obesity. The efferent sympathetic pathway does not uniformly act on all tissues; different tissues can receive different levels of sympathetic drive at the same time. This is an important concept in the discussion of the pharmacotherapy of obesity. Despite decades of work the medicine chest contains only one pill for the long term treatment of obesity, orlistat, a lipase inhibitor that prevents the absorption of lipid from the gut and is itself not systemically absorbed. The central controlling system for thermogenesis has many potential intervention points. Several drugs, previously marketed, awaiting approval or in the earlier stages of development may have a thermogenic effect via activation of the sympathetic nervous system at some point in the thermoregulatory circuit and are discussed in this review. If the balance is weighted to the "wrong" side there is the burden of increased cardiovascular risk while a shift to the "right" side, if possible, will afford a thermogenic benefit that is conducive to weight loss maintenance. This article is part of a Special Issue entitled 'Central Control Food Intake' Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Estudos etnoictiológicos sobre o pirarucu Arapaima gigas na Amazônia Central Ethnoictiology studies on Pirarucu (Arapaima mock-ups in Central Amazon

    Directory of Open Access Journals (Sweden)

    Liane Galvão de Lima

    2012-09-01

    among commercial fishermen and coastal urban dwellers are subsistence aspects of type of power and size of fishing recruitment. We conclude that fishermen of central Amazonia have necessary knowledge that allow participatory management of bass, and a deep knowledge in behavioral, biological and ecological processes of this kind, so you can actually contribute to the participation of management in local fisheries.

  9. La deserción estudiantil en el programa de ingeniería de sistemas de la Universidad de la Amazonia (2012-I - 2015-I: una lectura institucional y antropológica del asunto

    Directory of Open Access Journals (Sweden)

    Verenice S

    2017-05-01

    Full Text Available Las políticas para el fortalecimiento de la educación superior, usualmente han estado dirigidas a aumentar la capacidad de cobertura de cada uno de los programas académicos, lo que se ha venido logrando paulatinamente. Sin embargo, la situación parece no ser tan ventajosa cuando se mantiene de manera constante los altos niveles de deserción estudiantil, siendo preocupante no tener claridades alrededor de las causales y así tomar decisiones que desencadenen en estrategias de mejora y atención a la problemática.  La presente investigación tomando como estudio de caso el Programa de Ingeniería de Sistemas de la Universidad de la Amazonia, hizo un abordaje de tipo mixto empleando técnicas como arqueo de archivo, encuestas, observación estructurada y entrevistas, aplicadas a los desertores hizo una lectura sobre las causales de su abandono en el Programa. Al respecto, encontró que aunque como en los diferentes estudios de deserción aparecen factores como la dificultad económica o esta no era mi carrera, la situación es mucho más compleja y está relacionada con la vocación y el imaginario de vida que tienen los estudiantes.

  10. SECURITY THREATS IN CENTRAL ASIA

    Directory of Open Access Journals (Sweden)

    Çağla Gül Yesevi

    2013-07-01

    Full Text Available This study will analyze main security threats in Central Asia. It is obvious thatsince the end of Cold War, there have been many security threats in Central Asiaas internal weakness of Central Asian states, terrorism, transnational crime,economic insecurity, environmental issues, drug trafficking, ethnic violence,regional instability. This study will propose thatwith increasing interdependence,states need each other to solve these global security problems. In that sense,regional and sub-regional cooperation between Central Asian states and with otherregional actors has been witnessed. It is clear that the withdrawal of NATO fromAfghanistan will destabilize Central Asia. This study will investigate overallsecurity situation in Central Asia and affects andcontributions of regionalorganizations to Eurasian security

  11. Mexico and Central America.

    Science.gov (United States)

    Bronfman, M

    1998-01-01

    This article reviews the literature on migration and HIV/AIDS in Mexico and Central America, including Belize, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, and Panama. Most migrants travel to the US through Mexico. US-Mexico trade agreements created opportunities for increased risk of HIV transmission. The research literature focuses on Mexico. Most countries, with the exception of Belize and Costa Rica, are sending countries. Human rights of migrants are violated in transit and at destination. Migration policies determine migration processes. The Mexican-born population in the US is about 3% of US population and 8% of Mexico's population. About 22% arrived during 1992-97, and about 500,000 are naturalized US citizens. An additional 11 million have a Mexican ethnic background. Mexican migrants are usually economically active men who had jobs before leaving and were urban people who settled in California, Texas, Illinois, and Arizona. Most Mexican migrants enter illegally. Many return to Mexico. The main paths of HIV transmission are homosexual, heterosexual, and IV-drug-injecting persons. Latino migrants frequently use prostitutes, adopt new sexual practices including anal penetration among men, greater diversity of sexual partners, and use of injectable drugs.

  12. CENTRAL EUROPE: Role models

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1993-12-15

    Hungary is one of the newcomers to the CERN fold, having joined in 1992. The country's contributions are naturally in line with its slender resources and are not as immediately visible as those of the major Western European Member States. However the approach used and its consequent successes provide a good role model for a smaller nation in an international research environment. This was reflected on 24 September at a meeting of the European Committee for Future Accelerators (ECFA) convened in Budapest, continuing an ECFA tradition of holding meetings in national centres to learn more about the physics programmes of different countries. This tradition started with visits to major West European Centres, but last year ECFA held a meeting in Warsaw, its first in a central European country. By far the largest Hungarian population centre, Budapest is also a hub for national research in this sector, with university centres and the KFKI Research Institute for Particle and Nuclear Physics of the National Academy of Sciences. However important research work is also carried out in the eastern city of Debrecen. Hungarians look back to the classic investigations of Eotvos early this century as the starting point of their national tradition in fundamental physics. (In the mid-80s, these experiments briefly came back into vogue when there was a suggestion of an additional 'fifth force' contribution to nuclear masses.)

  13. CENTRAL EUROPE: Role models

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Hungary is one of the newcomers to the CERN fold, having joined in 1992. The country's contributions are naturally in line with its slender resources and are not as immediately visible as those of the major Western European Member States. However the approach used and its consequent successes provide a good role model for a smaller nation in an international research environment. This was reflected on 24 September at a meeting of the European Committee for Future Accelerators (ECFA) convened in Budapest, continuing an ECFA tradition of holding meetings in national centres to learn more about the physics programmes of different countries. This tradition started with visits to major West European Centres, but last year ECFA held a meeting in Warsaw, its first in a central European country. By far the largest Hungarian population centre, Budapest is also a hub for national research in this sector, with university centres and the KFKI Research Institute for Particle and Nuclear Physics of the National Academy of Sciences. However important research work is also carried out in the eastern city of Debrecen. Hungarians look back to the classic investigations of Eotvos early this century as the starting point of their national tradition in fundamental physics. (In the mid-80s, these experiments briefly came back into vogue when there was a suggestion of an additional 'fifth force' contribution to nuclear masses.)

  14. Big Data and central banks

    OpenAIRE

    David Bholat

    2015-01-01

    This commentary recaps a Centre for Central Banking Studies event held at the Bank of England on 2–3 July 2014. The article covers three main points. First, it situates the Centre for Central Banking Studies event within the context of the Bank’s Strategic Plan and initiatives. Second, it summarises and reflects on major themes from the event. Third, the article links central banks’ emerging interest in Big Data approaches with their broader uptake by other economic agents.

  15. Centralized vs. De-centralized Multinationals and Taxes

    DEFF Research Database (Denmark)

    Nielsen, Søren Bo; Raimondos-Møller, Pascalis; Schjelderup, Guttorm

    2005-01-01

    The paper examines how country tax differences affect a multinational enterprise's choice to centralize or de-centralize its decision structure. Within a simple model that emphasizes the multiple conflicting roles of transfer prices in MNEs - here, as a strategic pre-commitment device and a tax...

  16. The Regional Centrality of Vietnam’s Central Highlands

    DEFF Research Database (Denmark)

    Salemink, Oscar

    2018-01-01

    strategic value turned it into a battleground among various Vietnamese parties, France, and the United States. It was here that the outcome of the Indochina wars was determined, but at a terrible price for the local population. After the adoption of economic reforms in reunified Vietnam the Central......Vietnam’s Central Highlands—or Tây Nguyên—area is usually described as remote, backward, and primitive, but this region has played a central role in the history of the surrounding states and the wider East and Southeast Asia region. Far from isolated, the Central Highlands engaged in trade...... various rivalrous polities now known as Vietnam, Champa, Cambodia, Laos, and Thailand, the area occupied a strategic position in the wider mainland Southeast Asia region. With the emergence of a unified, neo-Confucianist Vietnamese state the region lost its centrality until the late colonial era, when its...

  17. Central nervous system tumors

    International Nuclear Information System (INIS)

    Gavin, P.R.; Fike, J.R.; Hoopes, P.J.

    1995-01-01

    Central nervous system (CNS) tumors are relatively common in veterinary medicine, with most diagnoses occurring in the canine and feline species. Numerous tumor types from various cells or origins have been identified with the most common tumors being meningiomas and glial cell tumors. Radiation therapy is often used as an aid to control the clinical signs associated with these neoplasms. In general, these tumors have a very low metastatic potential, such that local control offers substantial benefit. Experience in veterinary radiation oncology would indicate that many patients benefit from radiation treatment. Current practice indicates the need for computed tomography or magnetic resonance imaging studies. These highly beneficial studies are used for diagnosis, treatment planning, and to monitor treatment response. Improvements in treatment planning and radiation delivered to the tumor, while sparing the normal tissues, should improve local control and decrease potential radiation related problems to the CNS. When possible, multiple fractions of 3 Gy or less should be used. The tolerance dose to the normal tissue with this fractionation schedule is 50 to 55 Gy. The most common and serious complications of radiation for CNS tumors is delayed radiation myelopathy and necrosis. Medical management of the patient during radiation therapy requires careful attention to anesthetic protocols, and medications to reduce intracranial pressure that is often elevated in these patients. Canine brain tumors have served as an experimental model to test numerous new treatments. Increased availability of advanced imaging modalities has spawned increased detection of these neoplasms. Early detection of these tumors with appropriate aggressive therapy should prove beneficial to many patients

  18. Dublin South Central (DSC)

    LENUS (Irish Health Repository)

    O'Gorman, Clodagh S M

    2010-12-01

    Children who appear healthy, even if they have one or more recognized cardiovascular risk factors, do not generally have outcomes of cardiovascular or other vascular disease during childhood. Historically, pediatric medicine has not aggressively screened for or treated cardiovascular risk factors in otherwise healthy children. However, studies such as the P-Day Study (Pathobiological Determinants of Atherosclerosis in Youth), and the Bogalusa Heart Study, indicate that healthy children at remarkably young ages can have evidence of significant atherosclerosis. With the increasing prevalence of pediatric obesity, can we expect more health problems related to the consequences of pediatric dyslipidemia, hypertriglyceridemia, and atherosclerosis in the future? For many years, medications have been available and used in adult populations to treat dyslipidemia. In recent years, reports of short-term safety of some of these medications in children have been published. However, none of these studies have detailed long-term follow-up, and therefore none have described potential late side-effects of early cholesterol-lowering therapy, or potential benefits in terms of reduction of or delay in cardiovascular or other vascular end-points. In 2007, the American Heart Association published a scientific statement on the use of cholesterol-lowering therapy in pediatric patients. In this review paper, we discuss some of the current literature on cholesterol-lowering therapy in children, including the statins that are currently available for use in children, and some of the cautions with using these and other cholesterol-lowering medications. A central tenet of this review is that medications are not a substitute for dietary and lifestyle interventions, and that even in children on cholesterol-lowering medications, physicians should take every opportunity to encourage children and their parents to make healthy diet and lifestyle choices.

  19. Central African Republic.

    Science.gov (United States)

    1989-11-01

    The Central African Republic contains 242,000 square miles, which rolling terrain almost 2000 feet above sea level. The climate is tropical, and it has a population of 2.8 million people with a 2.5% growth rate. There are more than 80 ethnic groups including Baya 34%, Banda 28%, Sara 10%, Mandja 9%, Mboum 9%, and M'Baka 7%. The religions are traditional African 35%, protestant 25%, Roman Catholic 25%, and Muslim 15%, and the languages are French and Sangho. The infant mortality rate is 143/1000, with expectancy at 49 years and a 40% literacy rate. The work force of 1 million is 70% agricultural, industry 6% and commerce and service 6% and government 3%. The government consists of a president assisted by cabinet ministers and a single party. Natural resources include diamonds, uranium, timber, gold, and oil, and major industries are beverages, textiles, and soap. Agricultural products feature coffee, cotton, peanuts, tobacco, food crops and livestock. Most of the population live in rural areas and most of the 80 ethnic groups have their own language. This is one of the world's least developed countries, with a per capita income of $375/year. The main problems with development are the poor transportation infrastructure, and the weak internal and international marketing systems. The US and various international organizations have aided in agriculture development, health programs, and family planning. US investment is mainly in diamond and gold mining, and although oil drilling has been successful it is not economically feasible at current prices.

  20. Geometric origin of central charges

    International Nuclear Information System (INIS)

    Lukierski, J.; Rytel, L.

    1981-05-01

    The complete set of N(N-1) central charge generators for D=4 N-extended super Poincare algebra is obtained by suitable contraction of OSp (2N; 4) superalgebra. The superspace realizations of the spinorial generators with central charges are derived. The conjugate set of N(N-1) additional bosonic superspace coordinates is introduced in an unique and geometric way. (author)

  1. Biogeography of squirrel monkeys (genus Saimiri): South-central Amazon origin and rapid pan-Amazonian diversification of a lowland primate.

    Science.gov (United States)

    Lynch Alfaro, Jessica W; Boubli, Jean P; Paim, Fernanda P; Ribas, Camila C; Silva, Maria Nazareth F da; Messias, Mariluce R; Röhe, Fabio; Mercês, Michelle P; Silva Júnior, José S; Silva, Claudia R; Pinho, Gabriela M; Koshkarian, Gohar; Nguyen, Mai T T; Harada, Maria L; Rabelo, Rafael M; Queiroz, Helder L; Alfaro, Michael E; Farias, Izeni P

    2015-01-01

    The squirrel monkey, Saimiri, is a pan-Amazonian Pleistocene radiation. We use statistical phylogeographic methods to create a mitochondrial DNA-based timetree for 118 squirrel monkey samples across 68 localities spanning all Amazonian centers of endemism, with the aim of better understanding (1) the effects of rivers as barriers to dispersal and distribution; (2) the area of origin for modern Saimiri; (3) whether ancestral Saimiri was a lowland lake-affiliated or an upland forest taxa; and (4) the effects of Pleistocene climate fluctuation on speciation. We also use our topology to help resolve current controversies in Saimiri taxonomy and species relationships. The Rondônia and Inambari centers in the southern Amazon were recovered as the most likely areas of origin for Saimiri. The Amazon River proved a strong barrier to dispersal, and squirrel monkey expansion and diversification was rapid, with all speciation events estimated to occur between 1.4 and 0.6Ma, predating the last three glacial maxima and eliminating climate extremes as the main driver of squirrel monkey speciation. Saimiri expansion was concentrated first in central and western Amazonia, which according to the "Young Amazon" hypothesis was just becoming available as floodplain habitat with the draining of the Amazon Lake. Squirrel monkeys also expanded and diversified east, both north and south of the Amazon, coincident with the formation of new rivers. This evolutionary history is most consistent with a Young Amazon Flooded Forest Taxa model, suggesting Saimiri has always maintained a lowland wetlands niche and was able to greatly expand its range with the transition from a lacustrine to a riverine system in Amazonia. Saimiri vanzolinii was recovered as the sister group to one clade of Saimiri ustus, discordant with the traditional Gothic vs. Roman morphological division of squirrel monkeys. We also found paraphyly within each of the currently recognized species: S. sciureus, S. ustus, and S

  2. Controlling centrality in complex networks

    Science.gov (United States)

    Nicosia, V.; Criado, R.; Romance, M.; Russo, G.; Latora, V.

    2012-01-01

    Spectral centrality measures allow to identify influential individuals in social groups, to rank Web pages by popularity, and even to determine the impact of scientific researches. The centrality score of a node within a network crucially depends on the entire pattern of connections, so that the usual approach is to compute node centralities once the network structure is assigned. We face here with the inverse problem, that is, we study how to modify the centrality scores of the nodes by acting on the structure of a given network. We show that there exist particular subsets of nodes, called controlling sets, which can assign any prescribed set of centrality values to all the nodes of a graph, by cooperatively tuning the weights of their out-going links. We found that many large networks from the real world have surprisingly small controlling sets, containing even less than 5 – 10% of the nodes. PMID:22355732

  3. Central presbycusis: an emerging view.

    Science.gov (United States)

    Gates, George A

    2012-07-01

    Age-related dysfunction of the central auditory system (central presbycusis) is common but rarely looked for by those who provide aural rehabilitation. Patients who complain of difficulty hearing in noise--the key symptom of central presbycusis--are generally disadvantaged with conventional rehabilitation. This symptom should be documented with commercially available speech-in-noise tests, which use materials that are uncomplicated to administer. Those patients who perform poorly on such tests should have a customized rehabilitation program aimed at optimizing their remaining communication abilities. Otolaryngologists who provide auditory rehabilitation may wish to consider expanding their practices to meet the communication needs of older patients with central presbycusis. Central presbycusis is an emerging area for basic and clinical research in auditory neurotology, particularly in the relation of cognitive dysfunction to impaired auditory processing.

  4. Central control of body temperature.

    Science.gov (United States)

    Morrison, Shaun F

    2016-01-01

    Central neural circuits orchestrate the behavioral and autonomic repertoire that maintains body temperature during environmental temperature challenges and alters body temperature during the inflammatory response and behavioral states and in response to declining energy homeostasis. This review summarizes the central nervous system circuit mechanisms controlling the principal thermoeffectors for body temperature regulation: cutaneous vasoconstriction regulating heat loss and shivering and brown adipose tissue for thermogenesis. The activation of these thermoeffectors is regulated by parallel but distinct efferent pathways within the central nervous system that share a common peripheral thermal sensory input. The model for the neural circuit mechanism underlying central thermoregulatory control provides a useful platform for further understanding of the functional organization of central thermoregulation, for elucidating the hypothalamic circuitry and neurotransmitters involved in body temperature regulation, and for the discovery of novel therapeutic approaches to modulating body temperature and energy homeostasis.

  5. Population genetics of Manihot esculenta ssp. flabellifolia gives insight into past distribution of xeric vegetation in a postulated forest refugium area in northern Amazonia.

    Science.gov (United States)

    Duputié, Anne; Delêtre, Marc; De Granville, Jean-Jacques; McKey, Doyle

    2009-07-01

    The Guianas have often been proposed as a forest refugium; however, this view has received little testing. Studies of population genetics of forest taxa suggest that the central part of French Guiana remained forested, while the southern part (currently forested) may have harboured more open vegetation. Insights into the population structure of species restricted to non-forested habitats can help test this hypothesis. Using six microsatellite loci, we investigated the population genetics of French Guianan accessions of Manihot esculenta ssp. flabellifolia, a taxon restricted to coastal savannas and to rocky outcrops in the densely forested inland. Coastal populations were highly differentiated from one another, and our data suggest a recent colonization of these savannas by M. esculenta ssp. flabellifolia in a west-to-east process. Coastal populations were strongly differentiated from inselberg populations, consistent with an ancient separation of these two groups, with no or low subsequent gene flow. This supports the hypothesis that the central part of the region may have remained forested since the Last Glacial Maximum, impeding the establishment of Manihot. Contrary to coastal populations, inselberg Manihot populations were strikingly homogeneous at a broad spatial scale. This suggests they were connected until recently, either by a large continuous savanna area or by smaller, temporary disturbed areas shifting in space.

  6. [Central diabetes insipidus: diagnostic difficulties].

    Science.gov (United States)

    Matoussi, N; Aissa, K; Fitouri, Z; Hajji, M; Makni, S; Bellagha, I; Ben Becher, S

    2008-06-01

    Central diabetes insipidus is rare in children. Characteristic features include polyuria and polydipsia due to arginine vasopressin deficiency. The differential diagnosis of polyuric states may be difficult. Etiologic diagnosis of central diabetes insipidus may be an equally difficult task. To specify the difficulties encountered in the diagnosis of central diabetes insipidus and to point out features of the etiologic work-up and of long-term follow-up of children with idiopathic central diabetes insipidus. A retrospective study of 12 children admitted with a polyuria/polydipsia syndrome to the pediatric - consultation and emergency unit of the children's hospital of Tunis between 1988 and 2005. Children with acquired nephrogenic central diabetes insipidus were excluded. Fourteen-hour fluid restriction test and/or desmopressin test were used without plasma vasopressin measurement. Eight patients were classified as having central diabetes insipidus, which was severe in seven children and partial in one girl. One patient was classified as having primary polydipsia. The diagnosis remains unclear in three patients. The etiological work-up in eight patients with central diabetes insipidus enabled the identification of Langerhan's-cell histiocytosis in two patients and neurosurgical trauma in one. The cause was considered idiopathic in five patients. The median follow-up of the five patients with idiopathic central diabetes insipidus was five years two months plus or minus six years seven months (range five months, 14.5 years). During this follow-up, neither brain magnetic resonance imaging scans findings nor anterior pituitary function have changed. Fluid restriction and desmopressin tests did not enable an accurate distinction between partial diabetes insipidus and primary polydipsia. Regular surveillance is warranted in patients with idiopathic central diabetes insipidus to identify potential etiologies.

  7. Centralized digital control of accelerators

    International Nuclear Information System (INIS)

    Melen, R.E.

    1983-09-01

    In contrasting the title of this paper with a second paper to be presented at this conference entitled Distributed Digital Control of Accelerators, a potential reader might be led to believe that this paper will focus on systems whose computing intelligence is centered in one or more computers in a centralized location. Instead, this paper will describe the architectural evolution of SLAC's computer based accelerator control systems with respect to the distribution of their intelligence. However, the use of the word centralized in the title is appropriate because these systems are based on the use of centralized large and computationally powerful processors that are typically supported by networks of smaller distributed processors

  8. Central European gas market perspectives

    International Nuclear Information System (INIS)

    Vanous, Jan

    1999-01-01

    This presentation deals with (1) Definition of the Central European market, (2) Factors driving up consumption of natural gas in Central and Eastern Europe, (3) Role of natural gas in regional energy consumption, (4) Position of natural gas in individual country markets, (5) Future sources of imported natural gas into the region. The Central European market are the eleven countries Albania, Bulgaria, Croatia, Czech Republic, Hungary, Macedonia, Poland, Romania, Serbia and Montenegro, Slovakia, and Slovenia, with a total population of 121 million. This market is comparable to combined France and Italy in terms of population, but only 30% of its size in terms of GDP

  9. Big Data and central banks

    Directory of Open Access Journals (Sweden)

    David Bholat

    2015-04-01

    Full Text Available This commentary recaps a Centre for Central Banking Studies event held at the Bank of England on 2–3 July 2014. The article covers three main points. First, it situates the Centre for Central Banking Studies event within the context of the Bank’s Strategic Plan and initiatives. Second, it summarises and reflects on major themes from the event. Third, the article links central banks’ emerging interest in Big Data approaches with their broader uptake by other economic agents.

  10. Produção de serrapilheira no Cerrado e Floresta de Transição Amazônia-Cerrado do Centro-Oeste Brasileiro Litterfall production in the Brazilian mid-western Amazonia-Cerrado transition forest

    Directory of Open Access Journals (Sweden)

    Carlos José da Silva

    2007-01-01

    Full Text Available O presente trabalho teve como objetivo verificar a variação da produção de serrapilheira de diferentes biomas: Cerrado (com as fitofisionomias Cerrado sensu stricto e Cerradão e Floresta de Transição Amazônia-Cerrado, em clima tropical. Para a determinação da produção de serrapilheira foram utilizados coletores de tela em náilon. Dados micrometereológicos foram coletados nas áreas de estudo. A produção de serrapilheira nos dois biomas mostrou acentuada sazonalidade, com as maiores produções ocorrendo durante a estação seca e menor durante a estação chuvosa. A maior produção de serrapilheira ocorreu na Floresta de Transição, seguida do bioma Cerrado. A fração de folhas foi mais representativa do que as frações de galhos, flores, frutos em ambas as áreas estudadas.The objective of the present work was to verify the variation of litterfall production of different biomass: a cerrado ("savanna" with vegetation types Cerrado sensu stricto ("orchard-like vegetation" and Cerradão ("woodland-like vegetation" and Amazonia-Cerrado transition forest in a tropical climate. To determine the litterfall production, we used nylon screen traps. Micrometereologic data was collected in both areas of study. The litterfall in two biomass revealed themselves as seasonal, with the highest productions occurring during the dry season and the lowest during the wet. The biggest litterfall occurred in the Transition Forest, followed by the Cerrado biome. Leaf fraction was more representative than twigs, flowers, fruits in both areas studied.

  11. Demographic tensions in Central America.

    Science.gov (United States)

    1986-08-01

    This discussion of Central America focuses on the rapid growth of its population, its stagnating economy, and those countries that are socioeconomically advanced. Between 1950-85 the population of Central America tripled, from 9.1 million to 26. 4 million, due to marked mortality declines and the absence of off-setting fertility declines. The distribution of Central Americas's growing populations sets its population growth apart from that of other developing regions. Currently, almost half of all Central Americans live in cities. Although the average growth rate for Central American countries has fallen and is expected to drop further, the decline does not counterbalance the effect of the absolute rise in population numbers. The average annual growth rate of more than 3% annually in the 1960s fell to about 2.6% in recent years, but this decline is due primarily to socioeconomically advanced Costa Rica and Panama. Central America's age structure further complicates the population crisis. About 43% of Central Americans are under the age of 15. When the increasingly larger young population group enters it reproductive years, the potential for future growth (albeit the falling rate of population increase) is unparalleled. UN population projections show the region's population at 40 million by the year 2000. The 1973 oil crisis began a downward spiral for the buoyant post World War II Central American economy. Between 1950-79, real per capita income growth in Central America doubled, with Central American economies growing an average of 5.3% annually. By the early 1980s, overseas markets of the trade-dependent countries of Central America had dried up due to protectionism abroad and slumping basic commodity prices. These and other factors plunged Central America into its current economic malaise of falling real per capita income, rising unemployment, curtailed export led economic growth, and a rising cost of living. In general, economic growth in Central America

  12. The Central Trigger Processor (CTP)

    CERN Multimedia

    Franchini, Matteo

    2016-01-01

    The Central Trigger Processor (CTP) receives trigger information from the calorimeter and muon trigger processors, as well as from other sources of trigger. It makes the Level-1 decision (L1A) based on a trigger menu.

  13. Central Exclusive Production at LHCb

    CERN Document Server

    INSPIRE-00106463

    2015-01-01

    Central Exclusive Production is a unique QCD process in which particles are produced via colourless propagators. Several results have been obtained at LHCb for the production of single charmonia, pairs of charmonia, and single bottomonia.

  14. Hepatostomy for central hepatic hematomas

    International Nuclear Information System (INIS)

    Gewertz, B.L.; Olsen, W.R.

    1975-01-01

    Two patients with central hepatic hematomas are presented. Hepatostomy tube drainage provided prompt healing of the cavities without complications. The technique is presented as a safe and effective alternative to hepatic resection without compromising the established principles of management

  15. Payments and Central Bank Policy

    DEFF Research Database (Denmark)

    Korsgaard, Søren

    This thesis consists of three chapters. The rst, "Paying for Payments", examines the role of interchange fees in payment card networks. The second, "Bank Liquidity and the Interbank Market" (co-authored with Mikael Reimer Jensen), investigates how banks' liquidity holdings at the central bank a ect...... outcomes in the money market. The third, "Collateralized Lending and Central Bank Collateral Policy", considers the emergence of credit constraints under collateralized lending, and how central banks use collateral policy to mitigate these constraints. While the chapters can be read independently......, they share common themes. Each chapter is concerned with payments in one way or another, each is concerned with the e ciency of market outcomes, and, to the extent that there is scope for improving these outcomes, each discusses the appropriate role for policy, in particular central bank policy....

  16. CENTRAL PLATEAU REMEDIATION OPTIMIZATION STUDY

    Energy Technology Data Exchange (ETDEWEB)

    BERGMAN, T. B.; STEFANSKI, L. D.; SEELEY, P. N.; ZINSLI, L. C.; CUSACK, L. J.

    2012-09-19

    THE CENTRAL PLATEAU REMEDIATION OPTIMIZATION STUDY WAS CONDUCTED TO DEVELOP AN OPTIMAL SEQUENCE OF REMEDIATION ACTIVITIES IMPLEMENTING THE CERCLA DECISION ON THE CENTRAL PLATEAU. THE STUDY DEFINES A SEQUENCE OF ACTIVITIES THAT RESULT IN AN EFFECTIVE USE OF RESOURCES FROM A STRATEGIC PERSPECTIVE WHEN CONSIDERING EQUIPMENT PROCUREMENT AND STAGING, WORKFORCE MOBILIZATION/DEMOBILIZATION, WORKFORCE LEVELING, WORKFORCE SKILL-MIX, AND OTHER REMEDIATION/DISPOSITION PROJECT EXECUTION PARAMETERS.

  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. Ethnomethodology as an emic guide to cultural systems: the case of the insects and the Kayapó Indians of Amazonia

    Directory of Open Access Journals (Sweden)

    Darrell A. Posey

    1982-01-01

    Full Text Available This paper is an attempt to briefly summarize the taxonomic features of the folk entomological classification system of the Kayapó Indians of Central Brazil. The folk system shows a correlation with scientific taxonomies, especially at levels of Class, Order and Family. Several morphological continua os "sequences" are evident and within these are found additional sub-groupings called "complexes". Of particular interest is the sequence labeled "ñy", which is analogous to the scientific Orders of Isoptera and Hymenoptera. Patterns for these groupings reflect important social and cultural values and are indicative of the significance of social insects (bees, ants, wasps and termites in the Kayapó belief system. It is suggested that taxonomic systems are guides to culturally significant domains and point to underlying social and cultural patterns. These patterns are reified by mythology and oral tradition, being encoded as recurring symbolic forms with natural prototypes. Thus an ethnomethodology to determine folk classification systems offers an emic approach to the investigation of cultures and reveals the inter-relationships between cognitive systems, mythology, ceremony, and natural symbols.

  19. Environmental impacts of thermal generation in the largest city of the Brazilian Amazon; Impactos ambientais da geracao termeletrica na maior cidade da Amazonia brasileira

    Energy Technology Data Exchange (ETDEWEB)

    Coelho, Ilsa Maria Valois; Cartaxo, Elizabeth Ferreira [Universidade Federal do Amazonas (NIEMA/UFAM), Manaus, AM (Brazil). Nucleo Interdisciplinar de Energia Meio Ambiente e Agua

    2010-07-01

    The developing process of the Manaus city is questioned from the authors' concern about the built environment and 'destroyed' by the diversity of human actions. Reflecting on the impacts of greenhouse gases in the atmosphere of the city of Manaus by thermoelectric plants, the main source of electricity in the state, the focus of this study is the urban atmosphere where physical and chemical phenomena accelerate the effects of pollution. It is based on two works: A) monitoring of emissions of gaseous pollutants emitted by Power Plant (UTE) Maua from the emission source. This is a project - 'Reducing Emissions of Gaseous Pollutants in Central Steam Power Plants' - conducted by the Interdisciplinary Center for Energy, Environment and Water of the Federal University of Amazonas (UFAM) approved by the Research and Development Program of the Concessionaire local power. B) the result of a Master thesis submitted to UFAM, 'Mapping the distribution of nitrogen dioxide in the city of Manaus' (MARINHO, 2007). This research has made an assessment of levels of distribution of NO{sup 2} in twenty points distributed in a strategic way, demonstrating that the minimum values were found in a region with little urban influence. The analysis of these two works subsidizes a preliminary research in analytical chemistry and attempts to demonstrate the need to advance the search for methods and techniques more consistent. This is an important step toward a policy of environmental management of atmospheric air that will complement future studies of air pollution in the capital of Amazonas. (author)

  20. Chapter 1. Central nervous system

    International Nuclear Information System (INIS)

    Planiol, T.; Veyre, A.; Plagne, R.

    1975-01-01

    The present situation with regard to explorations of the central nervous system by radioactive compounds is reviewed. For the sake of clarity the brain and cerebrospinal fluid examinations are described separately, with emphasis nevertheless on their complementarity. The tracers used in each of these examinations are listed, together with the criteria governing their choice. The different techniques employed are described. Scintigraphy is presented apart from gamma-angio-encephalography since it is not possible with rectilinear scintigraphs to observe the circulatory phase. The results are interpreted by an analysis of normal and pathological aspects of the different stages of the central nervous system [fr

  1. Situación de salud y nutrición de niños indígenas y niños no indígenas de la Amazonia peruana

    Directory of Open Access Journals (Sweden)

    Adrián Díaz

    2015-07-01

    Full Text Available OBJETIVO: Evaluar el estado nutricional de los menores de 5 años, indígenas y no indígenas, de dos provincias de la Amazonia peruana. MÉTODOS: Estudio descriptivo y transversal representativo de familias con niños menores de cinco años residentes en las provincias de Bagua y Condorcanqui en Perú. El estudio incluyó entrevista a la madre o cuidador del(os niño(s, evaluación antropométrica, hemoglobina en sangre capilar, búsqueda de parásitos intestinales en los niños menores de 5 años, acceso a los servicios de salud, antecedentes de infecciones respiratorias agudas y enfermedades diarreicas agudas, condición socioeconómica y consumo de sal inadecuadamente yodada. Mediante métodos lineares generalizados se identificaron los determinantes de la desnutrición crónica y anemia infantil en cada población de estudio. RESULTADOS: Se evaluaron 986 familias y 1 372 niños. La prevalencia de desnutrición crónica fue mayor en la población indígena respecto de la no indígena (56,2% versus 21,9%, igual que la anemia (51,3% versus 40,9%. Los determinantes de la desnutrición crónica fueron diferentes en ambas poblaciones. En indígenas, prevaleció la edad mayor a 36 meses (OR 2,21; IC95% 1,61-3, 04 y vivienda inadecuada (OR 2,9; IC95% 1,19-7,11, mientras que en los no indígenas, la pobreza extrema (OR 2,31; IC95% 1,50 - 3,55 y el parto institucional (OR 3,1; IC95% 2,00-4,83. CONCLUSIONES: Existen marcadas brechas entre la población indígena y la población no indígena respecto de las condiciones de vida, acceso a servicios de salud y estado nutricional de menores de 5 años. Se requiere asignar particular atención a la población indígena a fin de adecuar las modalidades de entrega de los programas y servicios que ofrece el Estado en dichos contextos.

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

    Directory of Open Access Journals (Sweden)

    Reinaldo Imbrozio Barbosa

    2005-06-01

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

  3. Educated Cities and Regional Centralization

    DEFF Research Database (Denmark)

    Eriksen, Jesper

    centralization where the shares of students rose significantly more in urban municipalities than non-urban municipalities. The highest shares of students as well as fastest increases were seen in the municipalities of the four largest cities, Copenhagen, Århus, Odense, and Aalborg. At the national level...

  4. Fire management in central America

    Science.gov (United States)

    Andrea L. Koonce; Armando González-Cabán

    1992-01-01

    Information on fire management operations in Central America is scant. To evaluate the known level of fire occurrence in seven countries in that area, fire management officers were asked to provide information on their fire control organizations and on any available fire statistics. The seven countries surveyed were Guatemala, Belize, Honduras, El Salvador, Nicaragua,...

  5. Central amygdala, stress and adaption

    NARCIS (Netherlands)

    Roozendaal, Benno

    1992-01-01

    In this thesis the results were presented of studies that were designed to provide more insight in the role of the central nucleus of the amygdala (CEA) in the adaptation to environmental demands. The experiments were performed in several situations, in which rats react either directly to aversive

  6. Central African Journal of Medicine

    African Journals Online (AJOL)

    The Central African Journal of Medicine is a quarterly refereed general medical journal which seeks to promote the practice and science of medicine in Africa. Emphasis is placed on general medical topics, reflecting common and important conditions in the region. The journal also covers related medical fields. Submissions ...

  7. Shared breastfeeding in central Africa

    NARCIS (Netherlands)

    Ramharter, Michael; Chai, Sanders K.; Adegnika, Ayola A.; Klöpfer, Anna; Längin, Matthias; Agnandji, Selidji T.; Oyakhirome, Sunny; Schwarz, Norbert G.; Grobusch, Martin P.; Issifou, Saadon; Kremsner, Peter G.

    2004-01-01

    In this study, shared breastfeeding is described asa novel risk factor for vertical HIV transmission. This cross-sectional survey conducted in the central African country Gabon found that 40% of lactating mothers also breastfed other children than their own, and as many children were additionally

  8. Music Libraries: Centralization versus Decentralization.

    Science.gov (United States)

    Kuyper-Rushing, Lois

    2002-01-01

    Considers the decision that branch libraries, music libraries in particular, have struggled with concerning a centralized location in the main library versus a decentralized collection. Reports on a study of the Association of Research Libraries that investigated the location of music libraries, motivation for the location, degrees offered,…

  9. Central New York's New Workforce

    Science.gov (United States)

    Center for an Urban Future, 2009

    2009-01-01

    Conducted in late 2008 in partnership with the Greater Syracuse Chamber of Commerce and the Mohawk Valley Chamber of Commerce, this is the largest survey ever taken of Central New York businesses regarding the English language skills of the area workforce. The online survey was emailed to several hundred local businesses; 126 responses were…

  10. Central index of dose information

    International Nuclear Information System (INIS)

    1991-01-01

    The Central Index of Dose Information (CIDI) is a national database of occupational exposure to radiation operated by the NRPB as agent for the Health and Safety Executive. It receives summarised information on the radiation doses to classified persons in Great Britain annually from Approved Dosimetry Services. This document is the first annual CIDI summary of the data, giving statistics for 1986. (UK)

  11. Copycats of the Central Himalayas

    NARCIS (Netherlands)

    P.A. Arora (Payal)

    2009-01-01

    textabstractThis case study highlights practices of a rarely documented group of neo-users of the Internet or newbies from Central Himalayas, serving as a catalyst for delving deeply into the act of ‘plagiarism’ in online learning By looking at such ‘learning’ practices away from schools, namely

  12. Central Libraries in Uncertain Times.

    Science.gov (United States)

    Kenney, Brian J.

    2001-01-01

    Discusses security and safety issues for public libraries, especially high-profile central facilities, in light of the September 11 terrorist attacks. Highlights include inspecting bags as patrons enter as well as exit; the need for security guidelines for any type of disaster or emergency; building design; and the importance of communication.…

  13. Composição florística de trechos florestais na borda sul-amazônica Floristic composition of forest patches in Southern Amazonia

    Directory of Open Access Journals (Sweden)

    Natália Macedo Ivanauskas

    2004-09-01

    Full Text Available Este estudo apresenta a composição florística de trechos de uma faixa de vegetação de transição existente na região centro-leste do Estado de Mato Grosso, mais precisamente no município de Gaúcha do Norte (13° 10'S e 53° 15' O, onde dá-se o contato entre a Floresta Ombrófila e a Floresta Estacional. O levantamento florístico foi realizado em março de 1999 e bimestralmente a partir de agosto de 1999 até março de 2001, em excursões com duração média de 5 dias, por meio de caminhadas na borda e no interior de florestas, sendo coletadas fanerógamas em fase reprodutiva. Também foram incluídas amostras vegetativas de espécies arbustivo-arbóreas, que não floresceram ou frutificaram durante o período de amostragem, amostradas em 3ha destinados ao levantamento fitossociológico. O levantamento florístico resultou em 72 famílias, 168 gêneros e 268 espécies. Do total de espécies, 66% apresentaram hábito arbóreo e 18% foram lianas. As ervas e arbustos praticamente restringiram-se às áreas de borda ou clareiras, somando 13%. Já a flora epifítica mostrou-se pouco expressiva (1%, quando comparada ao restante da Amazônia, em conseqüência do clima regional mais seco. Hemiepífitas, parasitas e palmeiras constituíram o percentual restante. Constatou-se que 39 espécies amostradas em Gaúcha do Norte ainda não haviam sido depositadas em herbários que mantém coleções representativas da flora matogrossense, enfatizando a carência de coletas nas áreas florestais do Estado.This paper shows the floristic composition of forest patches in a zone of transition vegetation which exists in the central-east region of Mato Grosso state, more specifically in the municipality of Gaúcha do Norte (13° 10'S and 53° 15' W where it connects the tropical rain-forest and the seasonal forest. The floristic survey was performed in March 1999 and bisemesterly from August 1999 to March 2001 (during excursions of an average of five days

  14. Duração do ciclo de vida de Cornops aquaticum (Bruner, 1906 (Orthoptera: Acrididae: Leptysminae e aspectos de seu comportamento alimentar na Amazônia central Life cycle of Cornops aquaticum (Bruner, 1906 (Orthoptera: Acrididae: Leptysminae and aspects of its food behavior at Central Amazonia

    Directory of Open Access Journals (Sweden)

    Maria de Fátima Vieira

    2003-12-01

    Full Text Available O gafanhoto Cornops aquaticum (Bruner, 1906 (Orthoptera: Acrididae: Leptysminae completa seu ciclo de vida em Eichhornia (Pontederiaceae. Em experimentos ao ar livre, durante o período da enchente, foi verificado que a cópula pode durar entre 40 a 120 minutos. Cada postura tem em média 13,4 ovos (+/- 3,2 e o período de incubação durou 34,1 dias (+/- 1,97. A duração média do desenvolvimento de ovo a adulto foi de 156,2 dias, sendo 34,1 do estágio de ovo, 53,4 do estágio ninfal e 68,7 do estágio adulto. Alimentou-se de 6 espécies de macrófitas aquáticas dentre as 13 oferecidas. Ninfas (N e Adultos (A sobreviveram mais dias em Pistia stratiotes (N = 43 % até 30 dias e A =1 % até 27 dias e Pontederia sp. (N = 85 % e A = 40 % até 24 dias que em Limnobium sp. (N =13% e A =10 % até 12 dias, Ludwigia sp. (N =3 % até 24 dias e A =15 % até 9 dias, Azolla sp. (N =35 % até 9 dias e A =15 % até 12 dias e Paspalum repens (N =3 % até 21 dias e A =5 % até 24 dias.Life cycle of the grasshopper Cornops aquaticum (Bruner, 1906 (Orthoptera: Acrididae: Leptysminae is dependent on Eichhornia (Pontederiaceae. Experiments were carried outdoors during receding water, the Mating last for about 40 and 120 minutes. The ootheca has an average of 13.4 (+/- 3.2 eggs. Incubation lasted for 34.1 days (+/- 1.97. Mean durations of total development from egg to adult was 156.2 days, being 34.1 in the egg stage, 53.4 in the ninphal stage, and 68.7 in the adult stage. Nymphs (N and adults (A accepted only six aquatic macrophytes out of 13 species offered during 30 days; survived more time in Pistia stratiotes (N = 43 %, 30 days and A = 1 %, 27 days and Pontederia sp. (N = 85 % and A = 40 % until 24 days than Limnobium sp. (N =13% and A =10 % until 12 dias, Ludwigia sp. (N =3 %, 24 days and A =15 %, 9 days Azolla sp. (N =35 %, 9 days and A =15 %, 12 days and Paspalum repens (N =3 %, 21 days and A =5 %, 24 days.

  15. Biologia e ecologia de Anthodioctes moratoi Urban (Hymenoptera, Megachilidae, Anthidiini em matas contínuas e fragmentos na Amazônia Central, Brasil Biology and ecology of Anthodioctes moratoi Urban (Hymenoptera, Megachilidae, Anthidiini in continuous forests and forest fragments in Central Amazonia, Brazil

    Directory of Open Access Journals (Sweden)

    Elder Ferreira Morato

    2001-09-01

    Full Text Available Anthodioctes moratoi Urban, 1999 was described based on specimens collected in tlhe state of Amazonas during a study of the ecology of trap-nesting bees and wasps. Sampling was done between 1988 and 1990 north of Manaus, in areas of the "Forest Fragment Biological Dynamics Project". Wooden trap-nests were set in different heights inside continuous forests, forest fragments of different sizes, natural gaps inside continuous forest, and in cleared areas between forest fragments. A total of 61 nests were collected from which 33 males and 46 females emerged. The majority of nests was collected in continuous forests, at 15 m height, in holes 4.8 mm in diameter. No nest was collected in cleared areas. There was no correlation, neither between number of nests and monthly precipitation, nor between the monthly number of nests constructed in the two consecutive years. No nest was constructed between January and June 1989. Overall, this coincided with the period of least activity of other trap-nesting bees in the studied areas. The nests consisted of a linear series of brood cells with walls made of resinous material mixed with small wood chips. The average length of the provisioned cell was 13,4 mm. Half of this length was occupied by a pollen mass. The number of provisioned cells varied between two and nine. In 52% of the nests there was brood mortality in at least one cell. The phorid fly Phalacrotophora (Omapanta sp. was the only nest associate, emerged, from just one cell.

  16. Effects of change in primary forest cover on armadillo (Cingulata, Mammalia burrow use in the Central Amazon Efectos del cambio en la cobertura de bosque primario sobre el uso de las madrigueras por los armadillos (Cingulata, Mammalia en la Amazonia Central

    Directory of Open Access Journals (Sweden)

    María Clara Arteaga

    2012-03-01

    Full Text Available Transformation of primary forest to other vegetation types alters the availability and distribution of resources, and thus affects their use by species that inhabit the forest. Although armadillos are important earthmover mammals in the Amazon forest, and their burrows play an important physical and ecological role in the ecosystem, the impact of loss of primary forest cover on these organisms has been poorly understood. In order to evaluate the effects of change in the primary forest cover on burrow use by armadillos, we performed 2 censuses in 33 plots within 12 sites of different vegetation cover characteristics, and recorded burrow density and current use. A total of 109 armadillo burrows were found; the sites with higher percentages of primary forest cover showed a larger number of active burrows, although burrow density and the probability of establishing new burrows remained unaffected by this variable. Our results show that areas with higher quantities of primary forest habitat show more intense use by armadillos, probably due to the permanence time of individuals. These findings suggest that the viability of armadillo populations, as well as the role that these animals play within the ecosystem, may be affected in disturbed areas.La transformación del bosque primario a otro tipo de vegetación cambia la disponibilidad y distribución de los recursos, afectando su uso por especies que habitan el bosque. Los armadillos son el principal grupo de mamíferos escavadores del Amazonas y sus madrigueras cumplen un papel físico y ecológico en el ecosistema. Sin embargo, no se conoce el impacto de la pérdida del bosque sobre estos organismos. Con el fin de evaluar el efecto de los cambios en la cobertura de bosque primario sobre el uso de sus madrigueras, realizamos 2 censos en 33 parcelas dentro de 12 localidades con diferentes coberturas vegetales y reportamos la densidad y el estado de uso de las madrigueras. Encontramos 109 madrigueras y observamos un mayor número de éstas activas en áreas con mayor cobertura de bosque primario. Entre tanto, la densidad y la probabilidad de fundar nuevas madrigueras no se vio afectada por el tipo de cobertura forestal. Nuestros resultados indican que áreas con mayor cobertura de bosque primario exhiben un uso más intenso por armadillos, probablemente por una mayor permanencia de los individuos. Esto sugiere que la viabilidad de las poblaciones de armadillos y el papel que desempeñan en el ecosistema, puede verse afectado en áreas con hábitat modificado.

  17. Uso de água subterrânea em sistema de abastecimento público de comunidades na várzea da Amazônia central The use of groundwater in public water supply system of floodplain communities in the central Amazonia

    Directory of Open Access Journals (Sweden)

    Rainier Pedraça de Azevedo

    2006-01-01

    Full Text Available O paradoxo das águas marca as populações amazônicas que habitam as várzeas. Se na cheia as águas abundam, na seca escasseiam, chegando desfalcar os ribeirinhos seja pela insuficiência e/ou por condições impróprias para consumo. Esse trabalho descreve o aproveitamento do manancial subterrâneo para abastecimento público, através de poço tubular construído na comunidade de várzea de Santo Antônio, no município de Urucará, Estado do Amazonas. O estudo demonstrou a ocorrência de variações nas características físico-químicas da água do poço durante um ciclo das de superfície da região, principalmente a elevação do teor de ferro total no período de cheia máxima, sendo esse um indicativo de falha no processo construtivo do poço, uma vez que a água subterrânea local apresenta condições satisfatórias para o consumo humano. O aproveitamento do manancial subterrâneo em sistemas de abastecimento de água em comunidades de várzea na Amazônia é tecnicamente viável, entretanto, carece de obras de captação corretas, visando a conservação da qualidade da água desse rico ecossistema.The Amazonian populations that live in the floodplains are marked by a water paradox. If in the flood season water is plentiful, during the drought period water is scarce, either not having enough for the people's needs or it is inappropriate for human consumption. This paper describes the use of groundwater for public water supply system through a tubular well built in Santo Antonio floodplain community, in the district of Urucará, Amazonas State. The study has shown the occurrence of variations in the water quality of the well during the cycle of the superficial water, mainly an increase in the level of iron. This indicates a fault in the building process of the well, given that the local groundwater has good quality for consumption. The use of groundwater in public supply system in the floodplain communities in the Amazon is technically feasible. However it needs proper well construction techniques in order to preserve the quality of the groundwater of that rich ecosystem.

  18. An evaluation eMergetics of Itacoatiara's city in the central Amazon, their plywood, and cultivated plain of basin of Madeira's river; Uma avaliacao eMergetica da cidade de Itacoatiara na Amazonia Central, sua industria de compensado e laminado e a varzea da bacia do rio Madeira

    Energy Technology Data Exchange (ETDEWEB)

    Comar, Vito

    1994-12-01

    The plywood production system of Itacoatiara's industry and the wooden extraction impact of cultivated plain of basin of Madeira's river are presented. The incorporated energy flows - eMergy are evaluated by the models mathematical simulation, which applies to specific indices derivation aiming at the comparison with other similar processes. Itacoatiara's city was going analyzed regarding the industry load energetics and of others urban components.

  19. An evaluation eMergetics of Itacoatiara's city in the central Amazon, their plywood, and cultivated plain of basin of Madeira's river; Uma avaliacao eMergetica da cidade de Itacoatiara na Amazonia Central, sua industria de compensado e laminado e a varzea da bacia do rio Madeira

    Energy Technology Data Exchange (ETDEWEB)

    Comar, Vito

    1994-12-01

    The plywood production system of Itacoatiara's industry and the wooden extraction impact of cultivated plain of basin of Madeira's river are presented. The incorporated energy flows - eMergy are evaluated by the models mathematical simulation, which applies to specific indices derivation aiming at the comparison with other similar processes. Itacoatiara's city was going analyzed regarding the industry load energetics and of others urban components.

  20. Efeito dos óleos vegetais de andiroba (Carapa sp. e Copaíba (Copaifera sp. sobre forídeo, pragas de colméias, (Diptera: Phoridae na Amazônia Central Effect of andiroba (Carapa sp. and copaiba's (Copaifera sp. vegetable oils on phorides, hives's prague (Diptera: Phoridae in Central Amazonia

    Directory of Open Access Journals (Sweden)

    Delci da Costa Brito Freire

    2006-01-01

    Full Text Available O conhecimento de substâncias repelentes para forídeos é um passo importante para a meliponicultura brasileira, pois esses insetos podem causar sérios danos às colméias de abelhas nativas. Os óleos de copaíba e andiroba, naturalmente encontrados na região amazônica, são muito utilizados pelos povos tradicionais da região como repelentes de insetos. Foi observado o efeito de dois óleos vegetais (andiroba e copaíba sobre a postura de ovos por fêmeas de forídeos em condições de laboratório. A postura das fêmeas foi realizada preferencialmente no substrato pólen e diferiu estatisticamente dos substratos contendo óleo de andiroba ou copaíba, nos quais houve considerável diminuição (até nenhuma postura, e do substrato contendo mel. Esses óleos são uma boa alternativa no controle preventivo e curativo dessa praga em colônias de Meliponineos, devido ao seu efeito repelente, ao baixo custo e disponibilidade na Região Amazônica.The knowlegment of repellants substances to phoride flies is an important step to the Brazilian stinglessbee beekeeping due to the serious damage to the native bee hives they can do. The copaiba and andiroba oils, found commonly in the Amazon region, are very employed by the traditional people as insects' repellants. We observed the effect of these oils over the phoride's laying in laboratory conditions. The female phoride's eggs occurred preferentially in the pollen substrate and statistically differed from those containing andiroba and copaiba oils, which was strongly reduced (until none eggs were laid, and from the substrate containing honey. These oils showed to be quite good alternative for this plague's preventive and curative control in stingless bee hives due to its repellant effect, low cost, and availability to get it in the region.

  1. Efeito da colheita seletiva de madeira sobre algumas características físicas de um latossolo amarelo sob floresta na Amazônia Central Effect of selective logging on some physical characteristics of a yellow latosol under rainforest in Central Amazonia State

    Directory of Open Access Journals (Sweden)

    Walane Maria Pereira de Mello-Ivo

    2006-10-01

    Full Text Available A colheita seletiva de madeira pode vir a ser uma forma sustentável de uso da terra para ecossistemas florestais da Amazônia, uma vez que permite a manutenção de parte considerável da biomassa florestal, diminuindo, assim, a perturbação nas áreas exploradas. Neste sentido, o presente estudo teve como objetivo avaliar o efeito da exploração seletiva de madeira sobre as características físicas de um Latossolo Amarelo. A área de estudo localiza-se a cerca de 80 km ao norte de Manaus e a vegetação é do tipo Floresta Ombrófila Densa. O número de árvores retiradas com um trator de esteiras D6, por arraste, em 1993, variou de sete a dez árvores/ha (DAP > 55 cm. O delineamento experimental foi do tipo blocos ao acaso, com três repetições. Seis tratamentos foram avaliados, equivalendo às seguintes classes de perturbação identificadas na área: trilha de trator, centro de clareira, borda da clareira/floresta, borda da floresta/clareira, floresta remanescente e floresta-controle. A colheita seletiva de madeira provocou modificações nas características físicas do solo, principalmente nas trilhas de trator, e representou, em média, 13,8 % da área total explorada. Os valores de densidade do solo e resistência à penetração foram maiores para o solo sob estas áreas, enquanto a macroporosidade e o volume de água disponível para as plantas apresentaram-se menores do que nas demais classes de perturbação. Estas classes foram menos afetadas, não se estabelecendo diferenças significativas para as características físicas do solo entre estas e a floresta-controle, indicando, assim, a colheita seletiva como uma prática de menor impacto para o solo dos ecossistemas florestais da Amazônia.Selective logging may become a form of sustainable use of Amazon forest ecosystems since most part of the forest biomass is maintained and the impacts on the exploited area are lower than in comparison to those under other land uses. The objective of this study was to evaluate the effects of selective logging on some soil physical characteristics. The study area lies about 80 km north of Manaus and the vegetation is a humid tropical rainforest. Seven to ten trees/ha (DAP > 55 cm were felled and removed by a D6 bulldozer, in 1993. Six disturbance classes were defined in the logged plots, with three replicates each: tractor track, center of clearing, edge of clearing, edge of forest, remaining forest and control forest. Soil under tractor tracks represented 13.8 % of the exploited area, and showed higher values of bulk density, and penetration resistance, and lower macroporosity and available water for plants than the other disturbance classes. The other classes were less affected and no significant differences were observed between their soil properties and the control forest, indicating selective logging as a practice that causes less impact on soils of Amazon forest ecosystems.

  2. Efetividade de rizóbios e caracterização fenotípica dos isolados que nodulam feijão-caupi em solos da Amazônia Central Effectiveness and phenotypic characterization of cowpea rhizobia isolated from central Amazonian soils

    Directory of Open Access Journals (Sweden)

    Aloísio Freitas Chagas Junior

    2009-09-01

    Full Text Available O feijão-caupi (Vigna unguiculata é uma cultura importante na Amazônia Central, mas os rizóbios associados a essa leguminosa são poucos estudados. O objetivo deste estudo foi avaliar a efetividade e caracterizar fenotipicamente os isolados de rizóbio que nodulam feijão-caupi na região. As populações de rizóbio de Novo Ayrão proporcionaram as maiores produções de matéria seca da parte aérea e total, raiz, número de nódulos e peso dos nódulos secos nas plantas de feijão-caupi; porém, não diferiram do tratamento testemunha com N. Com base nos critérios fenotípicos avaliados, foi possível identificar uma ampla diversidade de populações de rizóbios contidos nos solos da Amazônia.Cowpea (Vigna unguiculata is an important legume cultivated in central Amazonia, but its rhizobia have been little studied. The present study aimed to evaluate the effectiveness and to characterize phenotypically the population of indigenous rhizobia that infect cowpea in the region. The rhizobia population from Novo Ayrão soils provided the highest shoot, root and total dry matter yields, number of nodules and nodule dry weights in cowpea plants; however, they were not different from those found for the control treatment with N. Based on phenotypic criteria, it was possible to identify a wide diversity of populations of rhizobia contained in Amazonian soils.

  3. Central and eastern European activities

    International Nuclear Information System (INIS)

    Rea, J.L.

    1993-01-01

    The Florida State University/Technical University of Budapest environmental research center, Center for Hungarian/American Environmental Research, Studies and Exchanges (CHAERSE), provides a resource base for information and technologies that is used to address near- and long-term environmental problems within the Department of Energy (DOE) complex and in Central and Eastern Europe. The CHAERSE is used as a technology transfer conduit for environmental restoration and waste management (ER/WM) problems and solutions. The International Technology Exchange Division (ITED) used the CHAERSE as one source of information for the identification of international ER/WM technologies being developed in Central and Eastern Europe. This was accomplished by matching high-priority problems in that region to high-priority problems in the DOE Complex; conducting symposia, meetings and workshops with international environmental experts; and identifying innovative technologies

  4. A centralized audio presentation manager

    Energy Technology Data Exchange (ETDEWEB)

    Papp, A.L. III; Blattner, M.M.

    1994-05-16

    The centralized audio presentation manager addresses the problems which occur when multiple programs running simultaneously attempt to use the audio output of a computer system. Time dependence of sound means that certain auditory messages must be scheduled simultaneously, which can lead to perceptual problems due to psychoacoustic phenomena. Furthermore, the combination of speech and nonspeech audio is examined; each presents its own problems of perceptibility in an acoustic environment composed of multiple auditory streams. The centralized audio presentation manager receives abstract parameterized message requests from the currently running programs, and attempts to create and present a sonic representation in the most perceptible manner through the use of a theoretically and empirically designed rule set.

  5. A Randomized Central Limit Theorem

    International Nuclear Information System (INIS)

    Eliazar, Iddo; Klafter, Joseph

    2010-01-01

    The Central Limit Theorem (CLT), one of the most elemental pillars of Probability Theory and Statistical Physics, asserts that: the universal probability law of large aggregates of independent and identically distributed random summands with zero mean and finite variance, scaled by the square root of the aggregate-size (√(n)), is Gaussian. The scaling scheme of the CLT is deterministic and uniform - scaling all aggregate-summands by the common and deterministic factor √(n). This Letter considers scaling schemes which are stochastic and non-uniform, and presents a 'Randomized Central Limit Theorem' (RCLT): we establish a class of random scaling schemes which yields universal probability laws of large aggregates of independent and identically distributed random summands. The RCLT universal probability laws, in turn, are the one-sided and the symmetric Levy laws.

  6. Centrality in earthquake multiplex networks

    Science.gov (United States)

    Lotfi, Nastaran; Darooneh, Amir Hossein; Rodrigues, Francisco A.

    2018-06-01

    Seismic time series has been mapped as a complex network, where a geographical region is divided into square cells that represent the nodes and connections are defined according to the sequence of earthquakes. In this paper, we map a seismic time series to a temporal network, described by a multiplex network, and characterize the evolution of the network structure in terms of the eigenvector centrality measure. We generalize previous works that considered the single layer representation of earthquake networks. Our results suggest that the multiplex representation captures better earthquake activity than methods based on single layer networks. We also verify that the regions with highest seismological activities in Iran and California can be identified from the network centrality analysis. The temporal modeling of seismic data provided here may open new possibilities for a better comprehension of the physics of earthquakes.

  7. Perihelium shifts in central potentials

    International Nuclear Information System (INIS)

    Amorim, A.E.A.; Ferreira, P.L.

    1987-01-01

    Motivated by the rigorous results on level ordering for arbitrary central potentials recently derived in the literature a classical treatment of the perihelium shifts is presented, based on the consideration of those orbits which lie in the vicinity of a circular orbit. The role played by the Laplacian of the potential is emphasized. By the same approach Bertrand's theorem is also discussed, in connection with Arnold's proof. (Author) [pt

  8. Information from the central stores

    CERN Multimedia

    GS Department

    2010-01-01

    All items sold in the CERN shop (Bldg. 33) are now available in the central stores (Bldg. 73) and can be purchased on-line via EDH “Material Request” or at the “Emergency Desk” of the stores on the ground floor of Bldg. 73. These items are visible in the CERN catalogue under the “SCEM” codes beginning with 92. Department of General Infrastructure Services (GS) GS-SEM Group

  9. Central Exclusive Production at LHCb

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00392425

    2017-01-01

    The LHCb detector, with its excellent momentum resolution and flexible trigger strategy, is ideally suited for measuring particles produced exclusively. In addition, a new system of forward shower counters has been installed upstream and downstream of the detector, and has been used to facilitate studies of Central Exclusive Production. Such measurements of integrated and differential cross-section in both Run 1 and Run 2 of the LHC, are summarised here.

  10. Volcanic hazards in Central America

    Science.gov (United States)

    Rose, William I.; Bluth, Gregg J.S.; Carr, Michael J.; Ewert, John W.; Patino, Lina C.; Vallance, James W.

    2006-01-01

    This volume is a sampling of current scientific work about volcanoes in Central America with specific application to hazards. The papers reflect a variety of international and interdisciplinary collaborations and employ new methods. The book will be of interest to a broad cross section of scientists, especially volcanologists. The volume also will interest students who aspire to work in the field of volcano hazards mitigation or who may want to work in one of Earth’s most volcanically active areas.

  11. Barter Economies and Centralized Merchants

    OpenAIRE

    Jose Noguera

    2000-01-01

    The main goal of this essay is to analyze the emergence of a barter economy, and the rise of centralized merchants and a barter redistribution system out of a primitive barter system. The environment is a spatial general equilibrium model where exchange is costly. Since exchange becomes more complicated as the scope of the economy increases, we prove that, after the economy reaches a critical size, the cost of trade expansion surpasses its benefits. This imposes limitations on the scope of th...

  12. Seismotectonic model of Central Europe

    International Nuclear Information System (INIS)

    Prochazkova, D.; Roth, Z.

    1994-01-01

    Earthquakes belong to natural disasters which are associated with tectonic processes in the interior of the Earth. They are extremely devastating in populated areas; they cause human losses and damage personal estates and the environment. To mitigate the potential effects of earthquakes it is necessary that relief and mitigation structures operate following an earthquake, but it is also essential to stimulate and enhance preparedness and prevention. Prevention includes the development of scenarios of potential earthquakes, hazard mapping, formulation of regulations, etc. Preparedness includes the installation and operation of warning systems, establishing communication networks to operate before, during, and after earthquakes. As nuclear technology belongs to high-risk technologies with regard to human health and the environment and its hazard substantially increases in consequence of earthquakes, in the siting of a nuclear plant engineering solutions are generally available to mitigate the potential vibratory effects through design. For the choice of a suitable engineering solution, reliable data must be processed by reliable techniques. The IAEA safety guide of the safety series No. 50-SG-S1(Rev. 1) specifies the demands on data and on their processing and also on the regional seismotectonic model. With a view of this the regional seismotectonic model of Central Europe was created. The paper presents regional geological characteristics of Central Europe and a chronological model of neotectonic movements in Central Europe with specification of neotectonic regional units and their present movements. Moreover, it contains earthquake characteristics for Central Europe and the specification of seismogenic movements. It was found that the genesis of local regions with occurrence of the strongest earthquakes is connected with several movement trends in the last 5 Ma. Six more or less tectonically separate regional units were revealed. The earthquake epicenters often

  13. MR findings of central nerocytoma

    International Nuclear Information System (INIS)

    Lee, Chang Hoon; Kim, Dong Ik; Lee, Byung Hee; Kim, Myung Soon

    1997-01-01

    Central neurocytoma is a reae neuronal differentiated intraventricular tomor of young adults. The purpose of this study was to evaluate the characteristic MR appearance of central neurocytoma. We retrospectively reviewed MR images of 12 patients with central neurocytoma, confirmed by ultrastructural and immunohistochemical study. We analyzed patient age, and on all sequences, tumor location, extension into the third ventricle, involvement of brain parenchyma, cyst, hemorrhage, vascular signal void and signal intensity ; and egree of Gd-enhancement was examined on MR images, pattern of calcification on CT, and neovascularity, tumor staining on angiography. Age distribution was wide ranging from 26 to 64 years ; the most frequent age group was the fourth decade (five patients). All tumors except one (in the third ventricle) were located in the lateral ventricle and most were seen in the region of the foramen of Monro (10 cases). Tumors showed extension into the third ventricle and involvement of parenchyma in three cases. The internal architecture of the tumor was heterogenous and consisted of cysts (83%), hemorrhage (25%) and vascular signal void (25%). The solid portion of the tumor showed variable signal intensity on T1-weighted images and iso or high signal intensity on T2- and proton density-weighted images. On MR imaging, mild to moderate heterogenous Gd-enhancement was seen in ten cases (83%), and on CT, a spotted, amorphous, nodular pattern of calcifications was seen in seven cases (63%). On angiography, neovasevlarity and tumor staining was seen in three cases (100%). The typical location of the lateral and third ventricles and MR imaging characteristics including variable signal intensity and heterogenous internal architecture are helpful in the diagnosis of central neurocytoma in young adults

  14. Central nervous system mesenchymal chondrosarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Salvati, M.; Frati, A.; Piccirilli, M.; Agrillo, A.; Brogna, C.; Occhiogrosso, G.; Giangaspero, F. [INM Neuromed IRCCS, Pozzilli (Italy). Dept. of Neurosurgery; Caroli, E. [Policlinico S. Andrea, Rome (Italy). Dept. of Neurological Sciences, Neurosurgery

    2005-06-15

    Central nervous system mesenchymal chondrosarcomas are rare malignant tumors that constitute a separate entity from the classical chondrosarcoma and myxoid variant. Clinical behaviour of central nervous system chondrosarcomas is still unknown. We describe two rare examples of intracranial mesenchymal chondrosarcoma with a review of the literature, in an attempt to clarify the clinical characteristics, prognosis and treatment of choice of these unusual tumors. Among the 55 reported cases, 23 had postoperative radiotherapy. Although there is no statistical significance according to the Log-Rank test (p=0.7), the patients treated with radiation therapy seem to have a better chance of survival. Patients who had adjuvant chemotherapy (only 5) showed survival times similar to those patients who had none. Although clinical behaviour of central nervous system chondrosarcomas remains to be defined, data from our series as well as literature show that radical removal is the best therapeutic choice. In addition, patients treated with postoperative radiotherapy seem to show a trend toward increased survival.

  15. Central nervous system mesenchymal chondrosarcoma

    International Nuclear Information System (INIS)

    Salvati, M.; Frati, A.; Piccirilli, M.; Agrillo, A.; Brogna, C.; Occhiogrosso, G.; Giangaspero, F.; Caroli, E.

    2005-01-01

    Central nervous system mesenchymal chondrosarcomas are rare malignant tumors that constitute a separate entity from the classical chondrosarcoma and myxoid variant. Clinical behaviour of central nervous system chondrosarcomas is still unknown. We describe two rare examples of intracranial mesenchymal chondrosarcoma with a review of the literature, in an attempt to clarify the clinical characteristics, prognosis and treatment of choice of these unusual tumors. Among the 55 reported cases, 23 had postoperative radiotherapy. Although there is no statistical significance according to the Log-Rank test (p=0.7), the patients treated with radiation therapy seem to have a better chance of survival. Patients who had adjuvant chemotherapy (only 5) showed survival times similar to those patients who had none. Although clinical behaviour of central nervous system chondrosarcomas remains to be defined, data from our series as well as literature show that radical removal is the best therapeutic choice. In addition, patients treated with postoperative radiotherapy seem to show a trend toward increased survival

  16. MR appearance of central neurocytoma

    International Nuclear Information System (INIS)

    Chang, K.H.; Han, M.H.; Kim, D.G.; Chi, J.G.; Suh, D.C.; Kim, S.J.; Cha, S.H.; Han, M.C.

    1993-01-01

    To provide a detailed description of the MR appearances of central neurocytoma, MR images of 13 patients with central neurocytoma were retrospectively reviewed and compared with CT examinations. The histology was confirmed by ultrastructural and immunohistochemical studies. In 12 patients the tumors were histologically benign and located in the anterior part of the lateral ventricle, 6 of which extended to the 3rd ventricle. There was one case of a histologically malignant variant involving the thalamus and lateral ventricle. The tumors were primarily solid, but contained cysts (85%, 11/13), calcifications (69%, 9/13), and signal void from tumor vessels (62%, 8/13), frequently producing heterogeneous signal intensity on both T1- and T2-weighted images. Most of the solid portion appeared isointense or slightly hyperintense relative to the cerebral cortex on all MR pulse sequences. Calcifications were iso- or hypointense on MR, making them difficult to characterize with MR alone. Intratumoral hemorrhage was seen in 2 patients on MR but not on CT. Contrast enhancement was variable in degree and pattern. Coronal and sagittal MR images were valuable in evaluating the tumor extent and origin site, and in planning the surgical approach. It is concluded that MR imaging appears to be more useful than CT in the overall evaluation of central neurocytoma, even though calcification is better characterized with CT. (orig.)

  17. Concept of the central clip

    DEFF Research Database (Denmark)

    Alegria-Barrero, Eduardo; Chan, Pak Hei; Foin, Nicolas

    2014-01-01

    AIMS: Percutaneous edge-to-edge mitral valve repair with the MitraClip(®) was shown to be a safe and feasible alternative compared to conventional surgical mitral valve repair. We analyse the concept of the central clip and the predictors for the need of more than one MitraClip(®) in our high.......8±10.7 years (30 males, 13 females; mean logistic EuroSCORE 24.1±11, mean LVEF 47.5±18.5%; mean±SD) were treated. Median follow-up was 385 days (104-630; Q1-Q3). Device implantation success was 93%. All patients were treated following the central clip concept: 52.5% of MR was degenerative in aetiology and 47....... The presence of a restricted posterior mitral valve leaflet (PML) was inversely correlated with the need for more than one clip (p=0.02). A cut-off value of ≥7.5 mm for vena contracta predicted the need for a second clip (sensitivity 83%, specificity 90%, p=0.01). CONCLUSIONS: The central MitraClip(®) concept...

  18. Centralized digital control of accelerators

    International Nuclear Information System (INIS)

    Melen, R.E.

    1984-01-01

    Upon careful examination of the architecture of SLAC's computer control systems, it becomes evident that the distribution of the systems' intelligence generally falls into tree-like layers. The first layer typically consists of a central computer complex incorporating one or more relatively large and powerful processors. The more modern systems use state-of-the-art 32-bit processors with several megabytes of RAM and several hundreds of megabytes of disk memory. Further, they support extensive user-friendly operating systems and program development facilities. The second layer typically consists of several smaller processors which are downloaded from the central complex and whose primary task is to provide data acquisition and distribution. The more modern systems are 16-bit processors with several hundred kilobytes of RAM and no disk memory. The third layer typically consists of several tens or hundreds of micro-processors, each dedicated to a single device. The micro-processors for these ''dedicated intelligent controllers'' are small and inexpensive and typically require less than 32 kilobytes of RAM or EPROM memory. Their hardware may be general purpose in nature or may be built into the architecture of the device itself. Figure 5 illustrates several of the relevant features of each of these layers. This paper serves to illustrate that SLAC is commited to the centralized digital control of its accelerators

  19. AAPT Diagnostic Criteria for Central Neuropathic Pain

    DEFF Research Database (Denmark)

    Widerstrom-Noga, Eva; Loeser, John D.; Jensen, Troels Staehelin

    2017-01-01

    Central neuropathic pain, which is pain caused by a lesion or disease of the central somatosensory nervous system, is a serious consequence of spinal cord injury, stroke, multiple sclerosis, and other conditions affecting the central nervous system. A collaborative effort between the Analgesic....... This article focuses on central neuropathic pain associated with spinal cord injury, stroke, and multiple sclerosis, but the AAPT framework can be extended to central pain due to other causes such as traumatic brain injury. The classification of central neuropathic pain is organized according to the AAPT...

  20. Crustal structure of Central Sicily

    Science.gov (United States)

    Giustiniani, Michela; Tinivella, Umberta; Nicolich, Rinaldo

    2018-01-01

    We processed crustal seismic profile SIRIPRO, acquired across Central Sicily. To improve the seismic image we utilized the wave equation datuming technique, a process of upward or downward continuation of the wave-field between two arbitrarily shaped surfaces. Wave equation datuming was applied to move shots and receivers to a given datum plane, removing time shifts related to topography and to near-surface velocity variations. The datuming procedure largely contributed to attenuate ground roll, enhance higher frequencies, increase resolution and improve the signal/noise ratio. Processed data allow recognizing geometries of crust structures differentiating seismic facies and offering a direct image of ongoing tectonic setting within variable lithologies characterizing the crust of Central Sicily. Migrated sections underline distinctive features of Hyblean Plateau foreland and above all a crustal thinning towards the Caltanissetta trough, to the contact with a likely deep Permo-Triassic rifted basin or rather a zone of a continent to oceanic transition. Inhomogeneity and fragmentation of Sicily crust, with a distinct separation of Central Sicily basin from western and eastern blocks, appear to have guided the tectonic transport inside the Caltanissetta crustal scale syncline and the accumulation of allochthonous terrains with south and north-verging thrusts. Major tectonic stack operated on the construction of a wide anticline of the Maghrebian chain in northern Sicily. Sequential south-verging imbrications of deep elements forming the anticline core denote a crust wedge indenting foreland structures. Deformation processes involved multiple detachment planes down to decoupling levels located near crust/mantle transition, supporting a presence of high-density lenses beneath the chain, interrelated to a southwards push of Tyrrhenian mantle and asthenosphere.

  1. 5. Regional focus: Central Europe

    International Nuclear Information System (INIS)

    Livernash, R.; Levy, B.S.; Hertzman, C.

    1992-01-01

    The industrial regions of Central Europe are so choked by pollution that the health of children is impaired and the lives of adults shortened. The paper discusses this situation under the following headings: industrial development and energy efficiency; dependence on coal; the extent of the damage (atmospheric pollution: low stacks, auto emissions; water pollution (agricultural sources); forest and soil damage; transboundary pollution); managing market forces (impact of higher prices, managing growth: the case of motor vehicles); looking for least-cost solutions (coping with coal, adjusting the fuel mix, energy conservation); developing effective laws and regulations

  2. Neurocitoma no sistema nervoso central

    Directory of Open Access Journals (Sweden)

    José Torquato Severo

    1973-03-01

    Full Text Available É relatado o caso de uma paciente com 6 anos de idade, hospitalizada com síndrome de hipertensão intracraniana. Após o exame neuro-radiológico que evidenciou processo expansivo frontal direito, a paciente foi submetida à cirurgia, durante a qual ocorreu o óbito. O exame histo-patológico do material retirado durante o ato operatório, permitiu o diagnóstico de neurocitoma, tumor raro no sistema nervoso central.

  3. Biomass energy in Central America

    Energy Technology Data Exchange (ETDEWEB)

    Blanco, J M [Biomass Users` Network, Regional Office for Central America and the Caribbean, San Jose (Costa Rica)

    1995-12-01

    The objective of this paper is to introduce the concept of biomass to energy issues and opportunities in Central America. In this region, made up of seven countries (Belize, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua and Panama), the biomass sector has the potential to play a crucial role in alleviating the environmental and development predicaments faced by all economies of the region. This paper assesses the available biomass resources at the regional and country levels and gives an overview of the current utilization of biomass fuels. It also describes the overall context in which the biomass-to-energy initiatives are immersed. At the regional level, biomass energy consumption accounts for more than 50% of total energy consumption. In regard to the utilization of biomass for energy purposes, it is clear that Central America faces a critical juncture at two levels, both mainly in rural areas: in the productive sector and at the household level. The absence of sustainable development policies and practices has jeopardized the availability of biomass fuels, particularly wood. Firewood is an important source of energy for rural industries such as coffee processing, which is one of the largest productive activities in the region. This paper comments on some of the most successful technological innovations already in place in the region, for instance, the rapid development of co-generation projects by the sugar cane industry, especially in El Salvador and Guatemala, the substitution of coffee husks for firewood in coffee processing plants in Costa Rica and El Salvador and the sustainable use of pine forests for co-generation in Honduras. Only one out of every two inhabitants in Central America now has access to electricity from the public grid. Biomass fuels, mainly firewood but also, to a lesser extent, other crop residues such as corn stalks, are the main source of energy for cooking and heating by most of the population. (It is foreseen that by the end

  4. Central precocious puberty in girls

    International Nuclear Information System (INIS)

    Argyropoulou, M.; Malandry, F.; Perignon, F.; Brunelle, F.; Brauner, R.; Rappaport, R.

    1990-01-01

    The treatment of central precocious puberty (CPP) in girls depends on its etiology and evolution, the latter based on the degree of accelerated bone maturation. The goal of this paper is to assess the diagnostic value of MR imaging in studying CPP in girls. Thirty-four girls with CPP were studied with MR imaging. Pituitary gland height (PGH) was measured on a sagittal midline image and compared with normal measurements. Correlations among clinical presentation, PGH, estradiol levels, and LH/FSH ratio were evaluated

  5. Biomass energy in Central America

    International Nuclear Information System (INIS)

    Blanco, J.M.

    1995-01-01

    The objective of this paper is to introduce the concept of biomass to energy issues and opportunities in Central America. In this region, made up of seven countries (Belize, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua and Panama), the biomass sector has the potential to play a crucial role in alleviating the environmental and development predicaments faced by all economies of the region. This paper assesses the available biomass resources at the regional and country levels and gives an overview of the current utilization of biomass fuels. It also describes the overall context in which the biomass-to-energy initiatives are immersed. At the regional level, biomass energy consumption accounts for more than 50% of total energy consumption. In regard to the utilization of biomass for energy purposes, it is clear that Central America faces a critical juncture at two levels, both mainly in rural areas: in the productive sector and at the household level. The absence of sustainable development policies and practices has jeopardized the availability of biomass fuels, particularly wood. Firewood is an important source of energy for rural industries such as coffee processing, which is one of the largest productive activities in the region. This paper comments on some of the most successful technological innovations already in place in the region, for instance, the rapid development of co-generation projects by the sugar cane industry, especially in El Salvador and Guatemala, the substitution of coffee husks for firewood in coffee processing plants in Costa Rica and El Salvador and the sustainable use of pine forests for co-generation in Honduras. Only one out of every two inhabitants in Central America now has access to electricity from the public grid. Biomass fuels, mainly firewood but also, to a lesser extent, other crop residues such as corn stalks, are the main source of energy for cooking and heating by most of the population. (It is foreseen that by the end

  6. Vulnerability in north- central Vietnam

    DEFF Research Database (Denmark)

    Casse, Thorkil; Milhøj, Anders; Nguyen, Thao Phuong

    2015-01-01

    This article examines changes in livelihood strategies in response to flooding. It does so on the basis of a household survey which was undertaken in three provinces in north central Vietnam. All households in the survey were regularly affected by flooding, but only poor households experience a l...... the impact of flooding in the provinces. The article ends by looking at the vulnerability-resilience debate concluding that the poorer households could enter a vulnerability loop, unless new strategies to cope with natural hazards are suggested....

  7. Central collisions of heavy ions

    International Nuclear Information System (INIS)

    Fung, Sun-yiu.

    1991-10-01

    This report describes the activities of the Heavy Ion Physics Group at the University of California, Riverside from October 1, 1990 to September 30, 1991. During this period, our program focuses on particle production at AGS energies, and correlation studies at the Bevalac in nucleus central collisions. We participated in the preparation of letters of intent for two RHIC experiments -- the OASIS proposal and the Di-Muon proposal -- and worked on two RHIC R ampersand D efforts -- a silicon strip detector project and a muon-identifier project. A small fraction of time was also devoted to physics programs outside the realm of heavy ion reactions by several individuals

  8. Dinâmica da mobilização de elementos em solos da Amazônia submetidos à inundação Dinamics of elements in soils from Amazonia after controlled inundation

    Directory of Open Access Journals (Sweden)

    Hedinaldo Narciso Lima

    2005-09-01

    Full Text Available Parte significativa de solos da Amazônia permanece saturada ou inundada por períodos que podem variar de alguns dias a vários meses, em decorrência de enchentes ou deficiência de drenagem em algumas áreas, resultando em alterações químicas, físicas e biológicas nos solos. Este trabalho foi conduzido com o objetivo de avaliar a dinâmica da mobilização de Al, Ca, Fe, K, Mg, Mn, Na, Si e P em solos da Amazônia submetidos a inundação. Amostras de vários solos foram submetidas à inundação durante seis meses. Alíquotas da solução foram coletadas periodicamente durante o tempo de inundação e determinaram-se os teores dos diversos elementos em solução. A inundação influenciou a cinética dos elementos, com aumento da mobilização dos mesmos, principalmente, nas primeiras semanas. Os teores de Fe em solução foram mais elevados para os solos mais ricos em Fe amorfo. Em amostras com baixos teores de Fe amorfo e baixo conteúdo de matéria orgânica, os teores de Fe em solução foram muito reduzidos. O teor de P em solução foi influenciado por todas as formas de P. O P ligado ao Fe foi a forma que maior influência exerceu sobre o teor de P solúvel. Os teores dos cátions Ca, Mg, K e Na, em solução, foram diretamente influenciados por seus respectivos teores trocáveis, bem como pela cinética do Fe e do Mn.Significant part of Amazonia soils stays partially or completely waterlogged for varying periods of days to months, as result of widespread inundation or drainage deficiency in some areas, causing changes in chemical, physical and biological properties. In this work, we aimed to evaluate the dynamics of mobilization of Al, Ca, Fe, K, Mg, Mn, Na, Si, P in soils subjected to controlled six months inundation. Soil solution aliquots were collected periodically during the inundation period, determining all elements in solution. The inundation influenced the kinetics of elements, increasing their mobilization, notably in

  9. The European Central Bank and the Eurosystem

    OpenAIRE

    Carol C. Bertaut

    2002-01-01

    The Eurosystem comprises the European Central Bank at its center as well as the national central banks of the twelve countries currently participating in monetary union. The European Central Bank was established in July 1998, six months before the beginning of Stage Three of economic and monetary union. Although decisions regarding monetary policy are made centrally by the Governing Council of the Eurosystem, the operational aspects of monetary policy-including open market operations, adminis...

  10. RELATION BETWEEN ISLAMIC BANK AND CENTRAL BANK

    OpenAIRE

    PAKSOY, H. Mustafa; ABAROSS, Nour

    2015-01-01

    This study deals with the nature of Islamic banks and their features, and requirements of these features in terms of control tools and methods appropriate with the particularity of their business and their relation with the traditional central bank. At the same time aims to view the relationship between Islamic bank and central bank. To explain this relation the researcher started to explain what is the central bank, objectives of central bank, and characteristics, what is Islamic bank and ob...

  11. Accountability of central banks: aspects and quantification

    Directory of Open Access Journals (Sweden)

    J. DE HAAN

    1999-06-01

    Full Text Available The work examines the relationship between central bank independence and accountability. The authors do this by using an indicator for central bank accountability based on the laws of 16 central banks. Central bank accountability is identified as having three distinct features, namely, the explicit definition and ranking of the objectives of monetary policy, the transparency of the actual monetary policy, and the final responsibility to monetary policy.

  12. Distributed trace using central performance counter memory

    Science.gov (United States)

    Satterfield, David L.; Sexton, James C.

    2013-01-22

    A plurality of processing cores, are central storage unit having at least memory connected in a daisy chain manner, forming a daisy chain ring layout on an integrated chip. At least one of the plurality of processing cores places trace data on the daisy chain connection for transmitting the trace data to the central storage unit, and the central storage unit detects the trace data and stores the trace data in the memory co-located in with the central storage unit.

  13. Occupational health in Central America.

    Science.gov (United States)

    Wesseling, Catharina; Aragón, Aurora; Morgado, Hugo; Elgstrand, Kaj; Hogstedt, Christer; Partanen, Timo

    2002-01-01

    The 12.4 million economically active population (EAP) of the seven Central American countries includes a large informal sector. Social security covers only 14-60%. No surveillance of occupational safety and health (OSH) hazards or accidents exists. Extrapolating the incidence of occupational accidents among insured Costa Rican workers to the Central American EAP yields two million accidents yearly, still a gross underestimate. Occupational diseases are underreported, misdiagnosed, and not recognized as such. A number of regional OSH programs aim at modernization of the labor administrations and address the formal sector, in particular textile maquila, in connection with free trade agreements. The weak role of the ministries of health is expected to strengthen under the Pan American Health Organization OSH program. Employers largely influence new policies. Workers' influence on OSH policies has been weak, with only about 10% unionization rate and scarce resources and OSH knowledge. Informal workers, however, are getting organized. OSH research is underdeveloped and not linked to policy making. Construction, agriculture, and general un/underemployment are considered priorities for intervention. The informal sector needs to be included in national and regional OSH policies. Regional collaboration and international development support are of strategic importance to achieve sustainable improvement in OSH.

  14. Central Equatorial Pacific Experiment (CEPEX)

    Energy Technology Data Exchange (ETDEWEB)

    1993-01-01

    The Earth's climate has varied significantly in the past, yet climate records reveal that in the tropics, sea surface temperatures seem to have been remarkably stable, varying by less than a few degrees Celsius over geologic time. Today, the large warm pool of the western Pacific shows similar characteristics. Its surface temperature always exceeds 27[degree]C, but never 31[degree]C. Heightened interest in this observation has been stimulated by questions of global climate change and the exploration of stabilizing climate feedback processes. Efforts to understand the observed weak sensitivity of tropical sea surface temperatures to climate forcing has led to a number of competing ideas about the nature of this apparent thermostat. Although there remains disagreement on the processes that regulate tropical sea surface temperature, most agree that further progress in resolving these differences requires comprehensive field observations of three-dimensional water vapor concentrations, solar and infrared radiative fluxes, surface fluxes of heat and water vapor, and cloud microphysical properties. This document describes the Central Equatorial Pacific Experiment (CEPEX) plan to collect such observations over the central equatorial Pacific Ocean during March of 1993.

  15. Central and forward tracking collaboration

    International Nuclear Information System (INIS)

    Foster, R.; Hanson, G.; Luehring, F.; Luo, X.; Martin, B.; Ogren, H.; Rust, D.R.; Wente, E.; Adrian, B.; Alexander, D.; Ells, F.; Erdos, E.; Ford, W.T.; Johnson, D.; Lohner, M.; Rankin, P.; Schultz, G.; Newcomer, F.M.; Van Berg, R.; Williams, H.H.; Arai, Y.; Hess, D.; Kadyk, J.A.; Palounek, A.P.T.; Wise, J.; Chapman, J.W.; Dunn, A.; Edwards, M.; Hiddleston, J.W.; Payne, B.T.; Amery, C.A.; Bailey, J.M.; Dainton, J.B.; Gabathuler, E.; Maxfield, S.J.; Morton, J.M.; Muir, A.; Patel, G.D.; Sanders, P.; Raine, C.; Saxon, D.H.; Hackworth, D.T.; Swensrud, R.L.; Newfield, S.; Sadler, C.; Va'vra, J.

    1991-01-01

    The goal of this subsystem R ampersand D project is to carry out a detailed study and design of a complete wire chamber tracking system covering pseudorapidity |η| ≤ 2.5 in a solenoidal detector for the SSC. Most of our group are now part of the Solenoidal Detector Collaboration (SDC), so the work has evolved into developing a tracking system conceptual design for the SDC detector. The design discussed in this report uses straw tube drift chambers for the central tracking region. Because of the high rates in the SSC environment, a small cell design is needed for wire chambers in the central region. Straw tubes as small cells offer many advantages because the sense wire is enclosed in a continuous cathode, and the wire tension due to the sense wire only can be supported without a massive structure. The straw tubes are grouped together to form superlayers in order to provide local track segments. The superlayers are composed of modules consisting of about two hundred straw tubes enclosed in a carbon fiber composite shell. Straw tubes have been used in previous experiments for small vertex drift chambers. However, they have never before been used for a large tracking system

  16. Central bank independence and inflation revisited

    NARCIS (Netherlands)

    Klomp, Jeroen; de Haan, Jakob

    We re-examine the relationship between central bank independence (CBI), proxied by the central bank governor's turnover rate and an indicator based on central bank laws in place, and inflation using a random coefficient model with the Hildreth-Houck estimator for more than 100 countries in the

  17. Central bank independence and inflation revisited

    NARCIS (Netherlands)

    Klomp, J.G.; Haan, de J.

    2010-01-01

    We re-examine the relationship between central bank independence (CBI), proxied by the central bank governor's turnover rate and an indicator based on central bank laws in place, and inflation using a random coefficient model with the Hildreth-Houck estimator for more than 100 countries in the

  18. "Christofest" New Yorgi Central Parkis / Rael Artel

    Index Scriptorium Estoniae

    Artel, Rael, 1980-

    2004-01-01

    12. II 2005. a. avatakse Christo ja Jeanne-Claude'i keskkonnainstallatsioon "The Gates" New Yorgi Central Parkis. Paralleelselt toimub Metropolitan Muuseumis näitus "Christo and Jeanne-Claude : The Gates, Central Park, New York", kus eksponeeritakse Central Parki installatsiooni ettevalmistavaid materjale: joonistusi, diagramme, fotosid jne

  19. Accountability of Central Banks : Aspects and Quantification

    NARCIS (Netherlands)

    de Haan, J.; Amtenbrink, F.; Eijffinger, S.C.W.

    1998-01-01

    This paper starts with a discussion of the various aspects of accountability of central banks. On the basis of this discussion we construct an indicator for accountability for 16 central banks, including the European Central Bank. It is shown that the degree of accountability differs considerably

  20. Natural and drought scenarios in an east central Amazon forest: Fidelity of the Community Land Model 3.5 with three biogeochemical models

    Science.gov (United States)

    Sakaguchi, Koichi; Zeng, Xubin; Christoffersen, Bradley J.; Restrepo-Coupe, Natalia; Saleska, Scott R.; Brando, Paulo M.

    2011-03-01

    Recent development of general circulation models involves biogeochemical cycles: flows of carbon and other chemical species that circulate through the Earth system. Such models are valuable tools for future projections of climate, but still bear large uncertainties in the model simulations. One of the regions with especially high uncertainty is the Amazon forest where large-scale dieback associated with the changing climate is predicted by several models. In order to better understand the capability and weakness of global-scale land-biogeochemical models in simulating a tropical ecosystem under the present day as well as significantly drier climates, we analyzed the off-line simulations for an east central Amazon forest by the Community Land Model version 3.5 of the National Center for Atmospheric Research and its three independent biogeochemical submodels (CASA', CN, and DGVM). Intense field measurements carried out under Large Scale Biosphere-Atmosphere Experiment in Amazonia, including forest response to drought from a throughfall exclusion experiment, are utilized to evaluate the whole spectrum of biogeophysical and biogeochemical aspects of the models. Our analysis shows reasonable correspondence in momentum and energy turbulent fluxes, but it highlights three processes that are not in agreement with observations: (1) inconsistent seasonality in carbon fluxes, (2) biased biomass size and allocation, and (3) overestimation of vegetation stress to short-term drought but underestimation of biomass loss from long-term drought. Without resolving these issues the modeled feedbacks from the biosphere in future climate projections would be questionable. We suggest possible directions for model improvements and also emphasize the necessity of more studies using a variety of in situ data for both driving and evaluating land-biogeochemical models.