Consulta: subjectFacets:"Amazon Basin"
Registros recuperados: 24
Data/hora: 09/06/2024 10:56:22

Morphometric variability in populations of Palaemonetes spp. (Crustacea, Decapoda, Palaemonidae) from the Peruvian and Brazilian Amazon Basin
Provedor de dados: 76
Autores: García-Dávila,Carmen Rosa; Magalhães,Célio; Guerrero,José Camilo Hurtado.
Morphometric variability among shrimp populations of the genus Palaemonetes Heller, 1869 from seven lakes (Huanayo and Urcococha, in Peru; Amanã, Mamirauá, Camaleão, Cristalino e Iruçanga, in Brasil) in the Amazon Basin, presumably belonging to Palaemonetes carteri Gordon, 1935 and Palaemonetes ivonicus Holthuis, 1950, were studied. The morphometric studies were carried out from the ratios obtained from the morphometric characters. Multivariated analysis (Principal Components Analysis-PCA, Discriminant Function Analysis and Cluster Analysis) were applied over the ratios. Intra- and interpopulation variations of the rostrum teeth, and the number of spines in the male appendix, were analyzed through descriptive statistics and bivariate analysis (Spearman...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Palaemonetes; Morphometry; Amazon Basin; Sibling species; Freshwater shrimp.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212005000300013

Four new combinations in Chomelia and Stenostomum (Rubiaceae, Guettardeae) from Central America, the Guianas and the Amazon Basin
Provedor de dados: 16
Autores: Delprete, P.G.; Achille, F.; Mouly, A.
According to current generic delimitations, supported by wood anatomy, palynology, and recent molecular phylogenies, Antirhea, traditionally treated as a Pantropical genus, is instead restricted to the Paleotropics. At the same time, the Neotropical species traditionally positioned in Antirhea should be positioned in Stenostomum. Following these definitions, Stenostomum is a genus with most of the species present in the Caribbean Region, and two species present in the Guianas, namely S. acreanum and S. guianensis, distributed throughout the Amazon Basin. In addition, according to these new generic delimitations, two species previously positioned in Guettarda and Antirhea need to be transferred to Chomelia, as C. triflora and C. ulei.
Tipo: Article / Letter to the editor
Palavras-chave: Amazon Basin; Chomelia; Floristics; French Guiana; Guettarda; Guettardeae; Guyana; Rubiaceae; South America; Stenostomum; Taxonomy.
Ano: 2010
URL: http://www.repository.naturalis.nl/record/525264

Hyperdominance in the Amazonian tree flora
Provedor de dados: 16
Autores: Steege, H. ter; Pitman, C.A.; Sabatier, D.; Baraloto, C.; Salomão, R.P.; Guevara, J.E.; Phillips, O.L.; Castilho, C.V.; Magnusson, W.E.; Mollino, J.-F.; Stevenson Diaz, P.R.; Costa , F.; Emilio, T.; Levis, C.; Schietti, J.; Souza, P.; Alonso, A.; Dallmeier, F.; Duque Montoya, A.J.; Fernandez Piedade, M.T.; Maas, P.; Araujo-Murakami, A.; Arroyo, L.; Gribel, R.; Fine, P.V.A.; Peres, C.A.; Toledo, M.; Aymard, G.A.; Baker, T.R.; Cerón, C.; Engel, J.; Petronelli, P.; Henkel, T.W.; Stropp, J.; Zartman, C.E.; Daly, D.; Neill, D.; Silveira, M.; Ríos Paredes, M.; Chave, J.; de Andrade Lima Filho, D.; Hoffman, B.; Møller Jørgensen, P.; Fuentes, A.; Schöngart, J.; Cornejo Valverde, F.; Di Fiore, A.; Jimenez, E.M.; Peñuela Mora, M.C.; Phillips, J.F.; Rivas, G.; Andel, T.R. van; Zent, E.L.; Hildebrand, P. von; Malhi, Y.; Prieto, A.; Rudas, A.; Ruschell, A.; Silva, N.; Vos, V.; Zent, S.; Oliveira, A.A.; Wang, O.; Cano Schutz, A.; Gonzales, T.; Trindade Nascimento, M.; Ramirez-Angulo, H.; Sierra, R.; Tirado , M.; Umaña Medina, M.N.; Heijden, G. van der; Vela, C.I.A.; Vilanova Torre, E.; Young, K.R.; Vriesendorp, C.; Baider, C.; Balslev, H.; Ferreira, C.; Mesones, I.; Torres-Lezama, A.; Urrego Giraldo, L.E.; Zagt, R.; Alexiades, M.N.; Monteagudo, A.; Hernandez, L.; Huamantupa-Chuquimaco, I.; Millikes, W.; Palacios Cuenca, W.; Pauletto, D.; Valderrama Sandoval, E.; Valenzuela Gamarra, L.; Dexter, K.G.; Feeley, K.; Lopez-Gonzalez, G.; Núñez Vargas, P.; Silman, M.R.; Montero, J.C.; Feldpausch, T.R.; Honorio Coronado, E.N.; Killeen, T.J.; Mostacedo, B.; Vasquez, R.; Assis, R.L.; Terborgh, J.; Wittmann, F.; Andrade, A.; Laurance, W.F.; Laurance, S.G.W.; Marimon, B.S.; Marimon , B.-H. Jr.; Célia Guimarães Vieira, I.; Leão Amaral, I.; Brienen, R.; Castellanos, H.; Cárdenas López, D.; Duivenvoorden, J.F.; Mogollón, H.F.; Dionízia de Almeida Matos, F.; Dávila, N.; García-Villacorta, R.
The vast extent of the Amazon Basin has historically restricted the study of its tree communities to the local and regional scales. Here, we provide empirical data on the commonness, rarity, and richness of lowland tree species across the entire Amazon Basin and Guiana Shield (Amazonia), collected in 1170 tree plots in all major forest types. Extrapolations suggest that Amazonia harbors roughly 16,000 tree species, of which just 227 (1.4%) account for half of all trees. Most of these are habitat specialists and only dominant in one or two regions of the basin. We discuss some implications of the finding that a small group of species—less diverse than the North American tree flora—accounts for half of the world’s most diverse tree community.
Tipo: Article / Letter to the editor
Palavras-chave: Hyperdominance; Amazonia; Amazon Basin; Guiana Shield; Trees; Commonness; Rarity; Richness; Tree species.
Ano: 2013
URL: http://www.repository.naturalis.nl/record/459385

Trichomycete fungi (Zygomycota) associated with mosquito larvae (Diptera: Culicidae) in natural and artificial habitats in Manaus, AM Brazil
Provedor de dados: 82
Autores: Pereira,Eleny da S.; Ferreira,Ruth L.M.; Hamada,Neusa; Lichtwardt,Robert W.
Fungal species of the class Trichomycete fungi (Zygomycota) are associated with the digestive tracts of Arthropoda. The relationships between these fungi and their hosts are still little understood: they may be commensal, beneficial or deleterious. Knowledge of the community structure of parasites/ pathogens and of the habitats of each species of Culicidae larvae can be important in studies that intend to use combined approaches to population control. Larvae of Culicidae and their associated trichomycete fungi were collected in Manaus County, AM, Brazil; sampling habitats included plants (natural habitat) and anthropic containers (artificial habitats). The total of 1,518 larvae were collected, 913 of which were in natural habitats and 605 were in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aquatic insect; Smittium culisetae; Breeding habitat; Larvae infection; Amazon Basin.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-566X2005000200022

Plasticity in the shape and growth pattern of asteriscus otolith of black prochilodus Prochilodus nigricans (Teleostei: Characiformes: Prochilodontidae) freshwater Neotropical migratory fish
Provedor de dados: 83
Autores: Costa,Rosa Maria Rodrigues da; Fabré,Nidia Noemí; Amadio,Sidinéia Aparecida; Tuset,Víctor Manuel.
ABSTRACT Using morphometric measurements and wavelets functions, the asterisci otoliths of curimatã, Prochilodus nigricans were analysed to identify the variation in shape and growth increment of individuals from Solimões, Japurá and Negro rivers of the Amazon basin, Brazil. The morphometric and morphological analyses did not reveal evidences of population segregation among rivers, but variations were found in the estimation of otolith growth increment. Also, the otolith shape showed a high variability between individuals, identifying four morphotypes. Morphotype 1 shows a more oval shape with a posterior zone clearly rounded; Morphotype 2 shows the posterior zone rounded, but the anterior end is more elongated; Morphotype 3 shows a completely different...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazon Basin; Growth increments; Morphotypes; Otolith shape; Phenotypes.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252018000400215

New species and records of Chimarra Stephens (Trichoptera, Philopotamidae) from Central Amazonia, Brazil
Provedor de dados: 92
Autores: Santos,Allan Paulo Moreira; Nessimian,Jorge Luiz.
Chimarra (Curgia) paucispina sp. nov., of the aurivittata group Flint, 1998 is described and illustrated from specimens collected in Amazonas State. The key to species of Chimarra (Curgia) Walker, 1860 presented by Flint was modified to include the new species. Chimarra (Chimarrita) chela Blahnik, 1997 and Chimarra (Curgia) jugescens Flint, 1998 are for first time reported for the Amazonas State. This is the first record of C. chela in Brazil.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazon Basin; Curgia; New species; Philopotamidae; Trichoptera.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0085-56262009000100006

A new species of Avima, the first record of Agoristenidae (Opiliones: Laniatores) from the state of Roraima, Brazil
Provedor de dados: 103
Autores: Porto,Willians; Colmenares,Pío A.
We describe Avima anitas sp. nov. based on material collected in the Brazilian state of Roraima, representing the first record of Agoristenidae in the State. The new species differs externally from other species of Avima by presenting­ one proximal tubercle on the mesal face of the male cheliceral segment II and a pair of dark spots partially covering mesotergal area III-IV. The genital differs from other species by the ventral small setae of the ventral plate, which are trifid instead of uniramous or bifid.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazon Basin; Harvestmen; Leiosteninae; Neotropical; Taxonomy.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702014000600009

A rapid assessment of the decapod fauna in the Rio Tahuamanu and Rio Manuripi Basins, with new records of shrimps and crabs for Bolivia (Crustacea, Decapoda, Palaemonidae, Sergestidae, Trichodactylidae)
Provedor de dados: 104
Autores: Magalhães,Célio.
Results of a decapad fauna survey canducted during the AquaRAP expeditian to Río Tahuamanu and Río Manuripi Basins, in the Departmentaf Panda, Balivia, in September, 1996 are presented. Ten species of shrimps and crabs, representing three families and six genera were faund. New recards for Balivia were Macrobrachium depressimanum Pereira, 1993, Macrobrachium brasiliense (Heller, 1862), Acetes paraguayensis Hansen, 1919, Sylviocarcinus devillei H. Milne-Edwards, 1853, Sylviocarcinus maldonadoensis (Pretzmann, 1978), and valdivia serrata White, 1847.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Balivia; Decapada; Diversity; Amazon Basin; Newrecord.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752002000400014

Amphibians and reptiles from Floresta Nacional de Pau-Rosa, Amazonas, Brazil: an important protected area at the heart of Amazonia
Provedor de dados: 36
Autores: FERREIRA,Gisele Cassundé; STURARO,Marcelo J.; PELOSO,Pedro L. Vieira.
ABSTRACT Amazonia harbors the largest and most diverse tropical forest in the world, but knowledge about the species diversity of the region is still far from ideal. Given this low level of faunal and floral knowledge, we present an annotated list of the species of amphibians and reptiles found in Floresta Nacional do Pau-Rosa (FNPR), along the Rio Paraconi, municipality of Maués, state of Amazonas, Brazil. Herpetofauna of the FNPR was sampled with pitfall traps, active search and occasional encounters from February 18 to March 28, 2009. A total of 270 specimens were collected, representing 39 species of amphibians and 24 species of reptiles. At least seven of the species collected at FNPR represented, at the time, unnamed taxa (four of which have now been...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazon Basin; Biodiversity; Checklist; Conservation; Herpetology.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672017000300259

A NEW SPECIES OF Rhacodiaptomus Kiefer, 1936, FROM THE BRAZILIAN AMAZON (CRUSTACEA:COPEPODA: CALANOIDA)
Provedor de dados: 36
Autores: SANTOS-SILVA,Edinaldo Nelson dos; ROBERTSON,Barbara.
A new species of Calanoid copepod, Rhacodiaptomus besti,is described from material collected in the Igarapé São Pedro, Rio Jamari, State of Rondônia, and Lago Amanã, Rio Japurá, State of Amazonas, in Western Amazonia. A detailed morphological analysis of the species was undertaken in order to provide a basis for future studies on inter and intrageneric relationships.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Calanoid copepod; Rhacodiaptomus; Amazon Basin; Brazil.
Ano: 1993
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59671993000100095

Agricultural land use and cover change in the Cerrado/Amazon ecotone: A case study of the upper Teles Pires River basin
Provedor de dados: 36
Autores: ZAIATZ,Ana Paula Sousa Rodrigues; ZOLIN,Cornélio Alberto; VENDRUSCULO,Laurimar Goncalves; LOPES,Tarcio Rocha; PAULINO,Janaina.
ABSTRACT The upper Teles Pires River basin is a key hydrological resource for the state of Mato Grosso, but has suffered rapid land use and cover change. The basin includes areas of Cerrado biome, as well as transitional areas between the Amazon and Cerrado vegetation types, with intensive large-scale agriculture widely-spread throughout the region. The objective of this study was to explore the spatial and temporal dynamics of land use and cover change from 1986 to 2014 in the upper Teles Pires basin using remote sensing and GIS techniques. TM (Thematic Mapper) and TIRS (Thermal Infrared Sensor) sensor images aboard the Landsat 5 and Landsat 8, respectively, were employed for supervised classification using the “Classification Workflow” in ENVI 5.0. To...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazon Basin; Remote sensing; GIS; Territorial management.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672018000200168

Chemical and physical attributes and calcium, magnesium, potassium, and phosphorus in the soil of murundu fields in Brazil
Provedor de dados: 36
Autores: SANTOS,Fernando André Silva; PIERANGELI,Maria Aparecida Pereira; SILVA,Fernando Luiz; SERAFIM,Milson Evaldo; SOUZA,Célia Alves de.
Fields of murundus (FM) are wetlands that provide numerous ecosystem services. The objectives of this study were to evaluate the chemical [organic carbon (OC), P, K+, Ca2+, Mg2+, Al3+ and H+Al] and physical [texture and bulk density (Bd)] soil attributes and calculate the organic matter (OM) and nutrient stock (P, Ca, Mg, and K) in soils of FM located in the Guapore River basin in Mato Grosso. Thirty-six sampling points were selected, and soil samples were collected from two environments: the murundu and plain area surrounding (PAS). At each sampling point, mini trenches of 0.5 × 0.5 × 0.4 m were opened and disturbed and undisturbed soil samples were collected at depths of 0-0.1, 0.1-0.2, and 0.2-0.4 m. In the Principal Component Analysis the variables...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazon Basin; Earthmound; Soil fertility; Wetland.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672015000200101

Provenance of heavy and clay minerals in bottom sediments of Green Lake, an Amazonian fluvial lake in Brazil
Provedor de dados: 36
Autores: MENDES,Anderson C.; DANTAS,Ângela B.; RIBEIRO,Anne Caroline S.; SANTOS,Livaldo O.; MENDES,Kamilla C.; MORAES,Dorsan dos Santos; ALMEIDA,Rodolfo M.
ABSTRACT Studies on provenance of minerals in Amazonian rivers focus mostly on suspended sediments, while processes that control bottom-sediment production and distribution are still little known. We determined the provenance of the bottom sediments of Green Lake, a micro-basin draining into the Tapajós River, in the eastern Brazilian Amazon. We used X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and, cathodoluminescence techniques to analyze clay, light and heavy minerals of 22 samples. The lake is L-shaped, with 5.5 m maximum depth, and predominance of mud over sand in the center. Quartz and feldspar were dominant in the light fraction, while zircon, tourmaline, kyanite, rutile, and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Alter do Chão Formation; Lacustrine sediment; Amazon Basin; Santarém; Mineral characterization.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672020000200159

Time-variations of equivalent water heights'from Grace Mission and in-situ river stages in the Amazon basin
Provedor de dados: 36
Autores: Almeida,Flavio Guilherme Vaz de; Calmant,Stephane; Seyler,Frédérique; Ramillien,Guillaume; Blitzkow,Denizar; Matos,Ana Cristina Cancoro; Silva,Joecila Santos.
Gravity Recovery and Climate Experiment (GRACE) mission is dedicated to measuring temporal variations of the Earth's gravity field. In this study, the Stokes coefficients made available by Groupe de Recherche en Géodésie Spatiale (GRGS) at a 10-day interval were converted into equivalent water height (EWH) for a ~4-year period in the Amazon basin (from July-2002 to May-2006). The seasonal amplitudes of EWH signal are the largest on the surface of Earth and reach ~ 1250mm at that basin's center. Error budget represents ~130 mm of EWH, including formal errors on Stokes coefficient, leakage errors (12 ~ 21 mm) and spectrum truncation (10 ~ 15 mm). Comparison between in situ river level time series measured at 233 ground-based hydrometric stations (HS) in the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Spatial geodesy; Hydrology; GRACE satellite; Amazon Basin.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672012000100015

New record of the fringed leaf frog, Cruziohyla craspedopus (Anura: Phyllomedusidae) extends its eastern range limit
Provedor de dados: 36
Autores: FRAGA,Rafael de; TORRALVO,Kelly.
ABSTRACT The fringed leaf frog, Cruziohyla craspedopus is rarely sampled in the Brazilian Amazon, probably due to low detection probability associated with its arboreal habit. The knowledge about the species’ distribution stems from successive additions of occasional occurrence records, which indicate that the species is widely distributed throughout Amazonia. We present new occurrence records to update the geographic range of the species, which is hereby extended 224 km to the northeast. We also present morphological data from collected specimens and discuss the updated range from the geographic and ecological points of view. We show that the range of the leaf frog crosses several main tributaries along the southern bank of the Amazonas River, although...
Tipo: Info:eu-repo/semantics/report
Palavras-chave: Amazon Basin; Detectability; Tapajós; Tree cover.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672019000300208

Revision of the genus Macrostomus Wiedemann (Diptera: Empididae: Empidinae): II. The pictipennis species-group
Provedor de dados: 36
Autores: Rafael,José Albertino; Cumming,Jeffrey M.
All species of Macrostomus Wiedemann allied with Macrostomus pictipennis (Bezzi), are treated in the pictipennis species-group. Three currently recognized species and four new species are included, namely M. cervicicauda Smith, M. cysticercus Smith, M. manauara, sp. nov. from Brazil (Amazonas and Pará states), M. pacaraima, sp. nov. from Brazil (Roraima, Amazonas and Pará states), M. pictipennis (Bezzi), M. smithi, sp. nov. from Guyana and Brazil (Roraima State) and M. utinga, sp. nov. from Brazil (Pará State). All primary types were examined and a key to species is presented.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazon Basin; Biogeography; Empididae; Macrostomus; Taxonomy.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672010000300023

Estimating of gross primary production in an Amazon-Cerrado transitional forest using MODIS and Landsat imagery
Provedor de dados: 42
Autores: DANELICHEN,VICTOR H.M.; BIUDES,MARCELO S.; VELASQUE,MAÍSA C.S.; MACHADO,NADJA G.; GOMES,RAPHAEL S.R.; VOURLITIS,GEORGE L.; NOGUEIRA,JOSÉ S.
The acceleration of the anthropogenic activity has increased the atmospheric carbon concentration, which causes changes in regional climate. The Gross Primary Production (GPP) is an important variable in the global carbon cycle studies, since it defines the atmospheric carbon extraction rate from terrestrial ecosystems. The objective of this study was to estimate the GPP of the Amazon-Cerrado Transitional Forest by the Vegetation Photosynthesis Model (VPM) using local meteorological data and remote sensing data from MODIS and Landsat 5 TM reflectance from 2005 to 2008. The GPP was estimated using Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) calculated by MODIS and Landsat 5 TM images. The GPP estimates were compared...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazon Basin; Cerrado; Carbon cycle; Climate change; Deforestation; Ecosystem function.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652015000401545

Genetic diversity and structuring in the arapaima (Osteoglossiformes, Osteoglossidae) population reveal differences between the Amazon and the Tocantins-Araguaia basins
Provedor de dados: 42
Autores: Nogueira,Fabrícia; Rêgo,Péricles S. do; Queiroz,Helder; Venere,Paulo; Varela,Eduardo S.; Sampaio,Iracilda; Schneider,Horacio; Araripe,Juliana.
Abstract  Arapaima is a widely-distributed fish of enormous economic importance in the Amazon region. In the present study, a total of 232 specimens were sampled, 121 from five sites in the Amazon basin and 111 from five sites in the Tocantins-Araguaia basin. The analyses investigated fragments of the Cytochrome b, Control Region, Cytochrome Oxidase I, NADH dehydrogenase subunit 2 and seven loci microsatellites. The analyses revealed the existence of two mitochondrial lineages within the general area, with no haplotypes shared between basins, and genetic variability significantly higher in the Amazon than in the Tocantins-Araguaia basin. Two divergent, but sympatric mitochondrial lineages were found in the Amazon basin, but only a single lineage in the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazon Basin; Tocantins-Araguaia Basin; Lineages; Structure population; Conservation.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652020000100703

Analysis of tectonic-controlled fluvial morphology and sedimentary processes of the western Amazon Basin: an approach using satellite images and digital elevation model
Provedor de dados: 42
Autores: Silva,Clauzionor L.; Morales,Norberto; Crósta,Alvaro P.; Costa,Solange S.; Jiménez-Rueda,Jairo R.
An investigation of the tectonic controls of the fluvial morphology and sedimentary processes of an area located southwest of Manaus in the Amazon Basin was conducted using orbital remote sensing data. In this region, low topographic gradients represent a major obstacle for morphotectonic analysis using conventional methods. The use of remote sensing data can contribute significantly to overcome this limitation. In this instance, remote sensing data comprised digital elevation model (DEM) acquired by the Shuttle Radar Topographic Mission (SRTM) and Landsat Thematic Mapper images. Advanced image processing techniques were employed for enhancing the topographic textures and providing a three-dimensional visualization, hence allowing interpretation of the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Morphotectonics; Morphostructural; Neotectonics; Amazon Basin.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652007000400010

Late quaternary dynamics in the Madeira river basin, southern Amazonia (Brazil), as revealed by paleomorphological analysis
Provedor de dados: 42
Autores: Hayakawa,Ericson H.; Rossetti,Dilce F.
Ancient drainage systems are being increasingly documented in the Amazon basin and their characterization is crucial for reconstructing fluvial evolution in this area. Fluvial morphologies, including elongate belts, are well preserved along the Madeira River. Digital Elevation Model from the Shuttle Radar Topography Mission favored the detection of these features even where they are covered by dense rainforest. These paleomorphologies are attributed to the shifting position of past tributaries of the Madeira River through avulsions. These radial paleodrainage networks produced fan-shaped morphologies that resemble distributary megafans. Distinguishing avulsive tributary systems from distributary megafans in the sedimentary record is challenging. Madeira´s...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Paleochannels; Amazon Basin; Madeira river; Remote sensing; Climate; Tectonics.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652015000100029

Species richness and composition of snake assemblages in poorly accessible areas in the Brazilian Amazonia
Provedor de dados: 49
Autores: Frazão,Luciana; Oliveira,Maria Ermelinda; Menin,Marcelo; Campos,Juliana; Almeida,Alexandre; Kaefer,Igor L.; Hrbek,Tomas.
Abstract: Snakes are a diverse group of terrestrial vertebrates of the order Squamata. Despite that, in the Amazonian biome, information about distribution and identification of snakes is limited when compared to other groups. Additionally, in Amazonia there is a sampling bias towards areas geographically close to urban centers and more densely populated areas. This in turn leads to false distribution gaps in poorly accessible areas of Amazonia. In this article we report the composition of snake assemblages in six areas of the Brazilian Amazonia, based on field sampling conducted over four years using standardized methods. We sampled 70 species from eight families: Typhlopidae (n=1), Leptotyphlopidae (n=1), Anillidae (n=1), Boidae (n=5), Colubridae (n=15),...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazon Basin; Brazil; Ophidia; Sampling methods; Squamata.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032020000100207

Trans-Amazon dispersal potential for Crotalus durissus during Pleistocene climate events
Provedor de dados: 49
Autores: Ingenloff,Kate; Peterson,A. Townsend.
Two disjunct distributional areas of Crotalus durissus(Neotropical rattlesnake) are in open habitats north and south of the Amazon Basin and are presently separated by humid rainforest habitats. We used ecological niche modeling to identify and investigate potential dispersal pathways for this species between the two areas during the late Pleistocene. Niches estimated for the two populations did not differ significantly. Our analyses indicated two possible, but a single most likely, potential routes of dispersal during the last glacial cycle. These results are important to understanding the history of Amazon Basin humid forest biotas, as they suggest agents of isolation among putative humid forest refugia in the form of dry forest and scrub, and associated...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ecological Niche Modeling; Amazon Basin; Biogeography; Forest Refugia; Last Glacial Maximum.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032015000200105

Nuclear-follower foraging associations among Characiformes fishes and Potamotrygonidae rays in clean waters environments of Teles Pires and Xingu rivers basins, Midwest Brazil
Provedor de dados: 49
Autores: Garrone Neto,Domingos; Carvalho,Lucélia Nobre.
During under and overwater observations were recorded nuclear-follower foraging associations among three species of characiform fishes - Chalceus epakros, Hemiodus semitaeniatus and Hemiodus unimaculatus - and a freshwater stingray species - Potamotrygon orbignyi - in the Teles Pires and Xingu rivers basins, Midwest Brazil. The teleost fishes were observed closely following the stingrays during the behavior of stirring the substrate to uncover invertebrates, which cause discrete sediment clouds. Apparently this sediment perturbation attracts the fishes that approached the foraging stingrays to feed on small preys and other food types exposed this way. This is a typical example of a commensal relationship in which one participant is benefited while the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Following behavior; Foraging habits; Interespecific interactions; Characidae; Hemiodontidae; Amazon Basin.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032011000400030

Screening for antimicrobial activity among bacteria isolated from the Amazon Basin
Provedor de dados: 58
Autores: Motta,Amanda S.; Cladera-Olivera,Florencia; Brandelli,Adriano.
Bacteria producing antimicrobial activity were identified among 86 isolates from aquatic environments of Brazilian Amazon Basin. Antimicrobial activity against at least one indicator strain was detected for 59 isolates (68.6%). Inhibitory activity was mostly against Gram-positive bacteria, such as Listeria monocytogenes and Bacillus cereus. The antimicrobial substances produced by 19 strains that showed higher inhibitory activity were partially characterized. These antimicrobial substances showed thermal resistance for up to 100°C and partial resistance to proteolytic treatment. Some antimicrobials were partially resistant to pronase E at 2 mg ml-1 or to treatment with trichloroacetic acid. Detection of antimicrobial activity on polyacrylamide gels...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antimicrobial activity; Listeria monocytogenes; Bacteriocins; Amazon Basin.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822004000300007