Distribuição de mercúrio em diferentes solos da Bacia do médio Rio Negro-AM: influência da matéria orgânica no ciclo biogeoquímico do mercúrio

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

Animais medicinais: conhecimento e uso entre as populações ribeirinhas do rio Negro, Amazonas, Brasil

O estudo tem por objetivo documentar o uso de animais na medicina caseira entre ribeirinhos do rio Negro, Amazonas, Brasil. Os dados foram coletados por meio de 92 entrevistas e de observações sobre o conhecimento e as práticas cotidianas de uso de animais medicinais. Cerca de 60 espécies animais são conhecidas com propósitos medicinais. O conhecimento é bem distribuído entre os sexos (homens e mulheres) e entre localidades (urbano e rural). O uso de animais medicinais está imerso em conceitos etiológicos e envolve uma complexa visão cosmológica do processo de cura. O êxodo rural e o acesso facilitado à medicina ocidental podem promover a perda dos conhecimentos tradicionais, o que pode ser mitigado através da valorização e da transmissão desses saberes às futuras gerações.

Entre tradições e modernidade: conhecimento ecológico local, conflitos de pesca e manejo pesqueiro no rio Negro, Brasil

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

Rediscovered after 77 years: Odontodiaptomus thomseni - a rare species of calanoid (Crustacea: Copepoda) from South America

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

Factors affecting Hg (II) adsorption in soils from the Rio Negro basin (Amazon)

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

Multi-method Study on Aquatic Humic Substances from the Rio Negro - Amazonas State/Brazil: Emphasis on Molecular-Size Classification of their Metal Contents

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

Comida de gente: preferências e tabus alimentares entre os ribeirinhos do Médio Rio Negro (Amazonas, Brasil)

No presente artigo, analiso os aspectos relacionados às escolhas e aversões alimentares entre as populações ribeirinhas assentadas no Rio Negro (Amazonas, Brasil). Foram entrevistadas 104 pessoas (57 homens e 47 mulheres) e observadas as práticas cotidianas quanto às preferências e restrições alimentares em 47 unidades domésticas. As escolhas alimentares são influenciadas por preferências individuais, fatores ecológicos, econômicos, sociais e culturais. Com relação ao sistema de tabus alimentares, os animais com caracteres híbridos ou difíceis de serem categorizados, como os peixes lisos e os animais de dieta generalista, são sujeitos a tabus. A sobreposição entre as diferentes correntes teóricas é utilizada para interpretar as variações estabelecidas entre as preferências e os tabus alimentares no Rio Negro.

Some constraints on the modeling using the uranium isotopes U-238 and U-234 for dating groundwaters from Guarany aquifer, South America

Groundwaters from the Guarany aquifer located at the South American continent and sampled at four wells with described geological sections in São Paulo State, Brazil, were chemically and isotopically analysed with two aims: to evaluate the quality of this important hydrological resource and to investigate the possibility of using the natural uranium isotopes U-234 and U-238 as a chronological tool, since the U-234/U-238 activity ratio and dissolved U content data in groundwater systems have generated models for dating purposes.

Results of the research cruises of FRV' Walther Herwig' to South America. LXXIV. Benthobatis kreffti n. sp (Chondrichthyes, Torpediniformes, Narcinidae), a new deep-water electric ray from off South Brazil and the third species of the genus.

Benthobatis kreffti n. sp. is described as the third species of this genus of blind deep-water electric rays, based on 150 specimens taken from the continental slope off South Brazil. The new species is the smallest within the genus (TL less than 300 mm) and is compared with both congeners, B. marcida from the north-western Atlantic and B. moresbyi from the northern Indian Ocean. B. kreffti is characterised beyond its small size mainly by plain dark colouration dorsally and a white underside, with dark margins of disc and pelvics, as well as by totally degenerated eyes almost no longer visible externally. The new species is diagnosed further by very low tooth counts of 9 to 13 rows and lack of folds, keels or ridges on sides of tail.

Doses from Rn-222, Ra-226, and Ra-228 in groundwater from Guarani aquifer, South America

Groundwater samples were analysed for Rn-222, Ra-226, and Ra-228 in Guarani aquifer spreading around I million kin 2 within four countries in South America, and it was found that their activity concentrations are lognormally distributed. Population-weighted average activity concentration for these radionuclides allowed to estimate a value: either slightly higher (0.13 mSv/year) than 0.1 mSv for the total effective dose or two times higher (0.21 mSv/year) than this limit, depending on the choice of the dose conversion factor. Such calculation adds useful information for the appropriate management of this transboundary aquifer that is socially and economically very important to about 15 million inhabitants living in Brazil, Argentina, Uruguay and Paraguay. (C) 2004 Elsevier Ltd. All rights reserved.

HOST-SPECIFICITY OF SEVERAL PSEUDACTEON (DIPTERA, PHORIDAE) PARASITES OF FIRE ANTS (HYMENOPTERA, FORMICIDAE) IN SOUTH-AMERICA

We tested the host specificity of several parasitic Pseudacteon scuttle flies in South America with 23 species of ants in 13 genera. None of these ant species attracted Pseudacteon parasites except Solenopsis saevissima (F. Smith) and to a lesser extent Solenopsis geminata (Fab.). This result is encouraging because it indicates that the Pseudacteon flies tested in this study would not pose an ecological danger to other ant genera if these flies were introduced into the United States as classical biological control agents of imported fire ants. This prediction of host specificity will, of course, need to be validated with potential hosts in the United States before these flies can be released.

Phylogenetic relationship of Sirodotia species (Batrachospermales, Rhodophyta) in North and South America

Sequence data from the RUBISCO large subunit (rbcL) plastid gene and nuclear small-subunit ribosomal DNA (SSU rDNA) were examined for five samples of Sirodotia delicatula from southeastern Brazil. Data from six North American samples previously identified as S. huillensis and S. suecica were also included in the analysis. Molecular data supported the continued recognition of these three species as separate entities, although one of the North American collections was misidentified. These results were shown to be congruent with morphology, chromosome number and geographic distribution. S. delicatula is more closely related to S. huillensis, both occurring in tropical-subtropical regions, than either to S. suecica with a temperate-boreal distribution. There was little rbcL variation within S. delicatula from Brazil and Costa Rica (the latter a collection previously identified as S. huillensis), with the six samples sequenced diverging from each other by 0-8 bp (0-0.67%). SSU rDNA data set did not provide sufficient resolution to infer phylogenetic relationships among the species of this group due to the low rates of variation (5 bp). Sirodotia was a well-supported clade (100% bootstrap or 1.00 a posteriori probability) based on rbcL sequences. Thus, the results confirm that Sirodotia is a monophyletic group within the Batrachospermales and we continue to recognize it at the generic level. The species S. delicatula, S. huillensis and S. suecica are morphologically and genetically distinct.