Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where José Francisco Berrêdo is active.

Publication


Featured researches published by José Francisco Berrêdo.


Acta Amazonica | 2014

Chemical composition of phytoplankton from the estuaries of Eastern Amazonia

Maria do Perpétuo Socorro Progene Vilhena; Marcondes Lima da Costa; José Francisco Berrêdo; Rosildo Santos Paiva; Pryscila Denise Almeida

Phytoplankton is important bioindicator of chemical and biological modifications of natural ecosystems. The objective of this study was to determine the total chemical composition of the phytoplankton of the Para and Mocajuba estuaries on the eastern coast of the Amazon region in the Brazilian state of Para. The chemical composition of the surface water, bottom sediments (total sample and bioavailable fraction), and the phytoplankton were determined by inductively coupled plasma optical emission spectrometry. Phytoplankton contained high concentrations of Ca, P, Mn, Fe, Zn, Al, Ba, and Pb. The phytoplankton of the Mocajuba estuary is rich in Fe (2,967-84,750 µg g -1 ), while those from the Para is rich in Al (1,216-15,389 µgg -1 ), probably reflecting divergent anthropogenic inputs. Both samples indicated a high bioconcentration factor derived from both the water and the bioavailable fraction, reflecting the efficiency of these organisms in the concentration of metals.


Revista Virtual de Química | 2015

Chemical Composition of the Bragantino Estuary Mangrove Sediment (PA) - Brazil

Ivan Carlos C. Barbosa; Regina Celi Sarkis Müller; Cláudio Nahum Alves; José Francisco Berrêdo; Pedro Walfir Martins e Souza Filho

Geochemical and mineralogical characteristics of the mangrove sediments are inherited from source areas, continental and marine, through the contribution of particulate or ionic material brought by the currents. The objective of this study was geochemically to characterize the sediment of a mangrove forest in north estern Pará State (Brazil). The sediment showed a predominance of finer fraction (58% silt and clay) and high concentrations of minerals SiO2 and Al2O3. And the elements trace Pb, Mo, Ga, As, Rb, Cs, Ba, V, Ni, Co, Zn, Cu, Sc and Y showed the typical values found in the region. The mangrove area present chemical characteristics of a site that does not suffer from human disturbance. A more detailed study, taking into account the seasonal factor, would help in observing the behavior of the species.


Tropical Oceanography | 2012

Análise das variáveis físico-químicas das águas intersticiais dos sedimento do rio Sucuriju – Cabo Norte - Amapá

Diego de Arruda Xavier; Núbia Chaves Guerra; José Francisco Berrêdo; Odete Fátima Machado da Silveira

O rio Sucuriju esta localizado na regiao do Cabo Norte situado no extremo leste do Estado do Amapa, presente na faixa costeira caracterizada por uma planicie inundavel fluvio-marinha, composta por sedimentos Quaternarios e vegetacao do tipo de manguezal. O estudo tem como objetivos, descrever as condicoes fisico-quimicas intersticiais, quantificar a porcentagem de materia orgânica no sedimento e correlacionar com os parâmetros analisados ao longo do rio. Foram recuperados sete testemunhos da foz do rio ate a proximidade do Lago Piratuba. Os resultados de salinidade variaram de 3 proximo ao lago a 25 nas proximidades da foz; o pH entre 3,95 a 8,23; o potencial redox entre -244 mV a 224 mV e a porcentagem de materia orgânica entre 2,00% a 31,19%. As variacoes do regime pluviometrico e a sazonalidade climatica interferem na intensidade da cunha salina dentro do estuario, sendo a principal causadora nas modificacoes dos parâmetros fisicoquimicos e na concentracao do teor de materia orgânica presente no sedimento. Devido as variacoes verticais desses parâmetros pode-se distinguir duas zonas com caracteristicas distintas: a zona oxidante localizada proximo a foz do rio, apresenta maior salinidade (media de 13,2), pH levemente alcalino (media de 7,48) e potencial redox ligeiramente oxidante (media de -30,4 mV), demonstra area de maior influencia oceânica; e a zona redutora localizada a montante do rio, com valores de salinidade menores (media 9,6), pH levemente acidos (media 9,93) e potencial redox ligeiramente redutores (media -130,2), demonstrando area com maior influencia continental. Palavras chaves: testemunhos, salinidade, pH, potencial redox, materia orgânica.


Acta Amazonica | 2008

Efeitos das variações sazonais do clima tropical úmido sobre as águas e sedimentos de manguezais do estuário do rio Marapanim, costa nordeste do Estado do Pará

José Francisco Berrêdo; Marcondes Lima da Costa; Maria do Perpétuo Socorro Progene


Brazilian Journal of Geology | 2004

Mineralogical, geochemical and palynological studies of late holocene mangrove sediments from northeastern Pará state, Brazil

Marcondes Lima da Costa; Hermann Behling; José Francisco Berrêdo; Marciléia Silva do Carmo; Natalino Valente Moreira de Siqueira


Journal of South American Earth Sciences | 2010

Continental and marine contributions to formation of mangrove sediments in an Eastern Amazonian mudplain: The case of the Marapanim Estuary

Maria do Perpétuo Socorro Progene Vilhena; Marcondes Lima da Costa; José Francisco Berrêdo


Brazilian Journal of Geology | 2008

Mineralogia e geoquímica de sedimentos de manguezais da costa amazônica: o exemplo do estuário do rio Marapanim (Pará)

José Francisco Berrêdo; Marcondes Lima da Costa; Maria do Perpétuo Socorro Progene Vilhena; Josiana Torres dos Santos


Environmental Geochemistry and Health | 2013

Accumulation and transfer of Hg, As, Se, and other metals in the sediment-vegetation-crab-human food chain in the coastal zone of the northern Brazilian state of Pará (Amazonia)

Maria S. P. Vilhena; Marcondes L. Costa; José Francisco Berrêdo


Regional Studies in Marine Science | 2017

The sources and accumulation of sedimentary organic matter in two estuaries in the Brazilian Northern coast

Maria P.S.P. Vilhena; Marcondes Lima da Costa; José Francisco Berrêdo; Rosildo Santos Paiva; Marcelo Z. Moreira


BOLETIM DO MUSEU DE GEOCIÊNCIAS DA AMAZÔNIA | 2017

BIOTRANSFERÊNCIA DE ELEMENTOS QUÍMICOS NOS ORGANISMOS DOS MANGUEZAIS DE CURUÇÁ

Maria do Perpétuo Socorro Progene Vilhena; Marcondes Lima da Costa; José Francisco Berrêdo; Rosildo Santos Paiva

Collaboration


Dive into the José Francisco Berrêdo's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Diego de Arruda Xavier

Federal University of Pernambuco

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge