Jean Valentin - Academia.edu (original) (raw)
Papers by Jean Valentin
Ecotoxicology and environmental safety, Jan 5, 2018
The relationship between metal accumulation and feeding behavior of macrofauna species is a key c... more The relationship between metal accumulation and feeding behavior of macrofauna species is a key concept to understand the bioavailability of different metals in the marine environment. We examined and compared the concentrations of eight heavy metals (Cr, Zn, Pb, Ni, Cu, Cd, Co and V) in different feeding guilds of macrofauna species, from a data set including 68 sandy beaches along the Rio de Janeiro coast. For this purpose, macrofauna species were classified in five feeding guild categories: carnivorous, herbivorous, detritivorous, suspensivorous and filter feeders. The coast of Rio de Janeiro was divided into seven regions according to environmental characteristics and historical human activities. For each region, generalized linear models were adjusted to test for differences between feeding guild abundances. Redundancy Analysis was performed to explore the relationship among the feeding guilds composition and the environmental variables. We found high variability in abundance a...
Neotropical Ichthyology
The feeding ecology of five elasmobranch species was studied on the southern coast of Rio de Jane... more The feeding ecology of five elasmobranch species was studied on the southern coast of Rio de Janeiro, southwestern Atlantic Ocean. The specimens were caught with a trawl or bottom longline between January 2006 and August 2007. The diets of Psammobatis rutrum and Psammobatis extenta appeared to be basically carcino-benthophagous, with a very small niche width. Rioraja agassizii was basically carcino/ichthyo-benthophagous, also with a narrow niche, including teleost fish and shrimp, but in different proportions according to age and sex. Rhizoprionodon lalandii was ichthyophagous, not influenced by age or sex. The analyses of these species and Atlantoraja cyclophora indicated two trophic groups: one composed of the smaller rays, P. extenta and P. rutrum, which basically fed on small crustaceans, polychaetes and nematodes; and the other of R. lalandii and the larger rays R. agassizii and A. cyclophora, which preyed on teleost fish and brachyurans.
Environmental Pollution, 2016
We evaluated concentrations of eight heavy metals Cr, Zn, Pb, Ni, Cu, Cd, Co and V, in tissues of... more We evaluated concentrations of eight heavy metals Cr, Zn, Pb, Ni, Cu, Cd, Co and V, in tissues of representative macrofauna species from 68 sandy beaches from the coast of Rio de Janeiro state. The links between contamination levels and community descriptors such as diversity, evenness, density and biomass, were also investigated. Metal concentrations from macrofaunal tissues were compared to maximum permissible limits for human ingestion stipulated by the Brazilian regulatory agency (ANVISA). Generalized linear models (GLM's) were used to investigate the variability in macrofauna density, richness, eveness and biomass in the seven different regions. A non-metric multidimensional scaling analysis (n-MDS) was used to investigate the spatial pattern of heavy metal concentrations along the seven regions of Rio de Janeiro coast. Variation partitioning was applied to evaluate the variance in the community assemblage explained by the environmental variables and the heavy metal concentrations. Our data suggested high spatial variation in the concentration of heavy metals in macrofauna species from the beaches of Rio de Janeiro. This result highlighted a diffuse source of contamination along the coast. Most of the metals concentrations were under the limits established by ANVISA. The variability in community descriptors was related to morphodynamic variables, but not with metal contamination values, indicating the lack of direct relationships at the community level. Concentration levels of eight heavy metals in macrofauna species from 68 sandy beaches on Rio de Janeiro coast (Brazil) were spatially correlated with anthropogenic activities such as industrialization and urbanization.
Hydrobiologia, 2004
A bacterial dynamics study was conducted in the southwest Atlantic Ocean off the Brazilian coast ... more A bacterial dynamics study was conducted in the southwest Atlantic Ocean off the Brazilian coast from October to December 1998 with samples collected at the depth of chlorophyll a maximum. The bacteria were counted by flow cytometry with the SYTO13 DNA dye and bacterial activity was measured as carbon production by the uptake of 3 H-leucine. The samples were also analysed for basic hydrographical variables. Bacterial counts varied from 2.1 to 9.7 × 10 5 cells ml −1 and bacterial production varied from 4.6 to 126.6 ng C L −1 h −1. Spatial distribution of nitrate, chlorophyll a, bacterial abundance and bacterial activity showed areas of water fertilization in the oligotrophic Atlantic Ocean. Statistical analysis of data characterized the division of the area in two by latitude 19 • S. On the north fertilizations are related to river discharge and on the south to the input of nutrients from deep waters. Remobilisation of nutrients in those spots results among all in higher biological activity. However the relation between bacterial abundance and activity is top-down controlled characterizing most of the waters as oligotrophic. Eddies showed by bacterial data can probably sustain the fisheries resources for the whole area. The influence of gradients across eddies on biological activity and food chain structure should be an important question to be studied in oligotrophic oceans.
Ciencia E Cultura, Mar 1, 1987
Oecologia Brasiliensis, 1995
Oecologia Brasiliensis, 1999
Oceanologica Acta, 1980
Un traitement statistique par la méthode des composantes principales a été appliqué aux données d... more Un traitement statistique par la méthode des composantes principales a été appliqué aux données de plancton d'une station fixe située dans l'upwelling de Cabo Frio (Brésil). Les trois premières composantes expliquant 39 %de la variance totale du plancton ont fait l'objet d'une interprétation. Il s'agirait de: (1) l'alternance des masses d'eau au cours des phases successives de résurgence et subsidence; la communauté planctonique des eaux chaudes du Courant du Brésil et celle des eaux profondes sont mises en évidence par ce premier facteur, (2) la présence d'une thermocline, facteur favorable au démarrage des poussées algales, (3) l'influence du fond par remise en suspension des sédiments à la suite d'une forte turbulence ou de courants, donnant origine à une communauté algale composée d'espèces du microphytobenthos.
Revista Brasileira De Biologia, 1997
ABSTRACT RESUMO Organismos da macrofauna bentônica são utilizados como indicadores ambientais por... more ABSTRACT RESUMO Organismos da macrofauna bentônica são utilizados como indicadores ambientais por responderem a distúrbios naturais e antropogênicos. Este artigo tem como objetivo levantar informações sobre a macrofauna bentônica em estuários, manguezais e lagoas costeiras prioritárias para conservação no Brasil, comparar o conhecimento entre as regiões do país e direcionar futuros trabalhos. Foram encontrados 136 trabalhos publicados entre 1950 – 2010, realizados em 33 das 61 áreas prioritárias. As regiões mais estudadas são sudeste e sul, sendo que a Baía de Paranaguá e Lagoa dos Patos ABSTRACT Macrobenthic organisms are useful indicators of estuarine environmental status as they respond predictably to many kinds of natural and human-induced disturbances. The goal of the present review is to assess the state of knowledge about these communities on priority estuaries, mangroves and coastal lagoons considered as priorities for conservation in Brazil; to compare the knowledge among Brazilian regions, and to suggest the needs for further studies. We found 136 studies published during 1950-2010, at 33 of 61 priority areas. The most studied regions are southeast and south, Paranaguá Bay and Patos Lagoon concentrate the major number of publication in diverse subjects related to soft-bottoms macrobenthic communities. Community ecological aspects are the least studied subject, and development of further studies on this theme are crucial. Priority areas for conservation need immediate incentives to basic research, in special north and northeast regions. Mainly studies aiming to in-crease knowledge on local communities including taxonomic descriptions, community characterization and spatio-temporal dis-tribution of macrobenthic species. Considering the ecological and economic importance of estuarine systems, studies aiming the knowledge of the biodiversity should be increased to aid the implementation of monitoring, recovery and conservation programs.
Base de dados : REPIDISCA. Pesquisa : 153209 [Identificador único]. Referências encontradas : 1 [... more Base de dados : REPIDISCA. Pesquisa : 153209 [Identificador único]. Referências encontradas : 1 [refinar]. Mostrando: 1 .. 1 no formato [Detalhado]. página 1 de 1, 1 / 1, REPIDISCA, seleciona. para imprimir. Id: 153209. Autor: Valentin ...
Oecologia Brasiliensis, 1995
Frontiers in Microbiology, 2015
Guanabara Bay is the second largest bay in the coast of Brazil, with an area of 384 km 2. In its ... more Guanabara Bay is the second largest bay in the coast of Brazil, with an area of 384 km 2. In its surroundings live circa 16 million inhabitants, out of which 6 million live in Rio de Janeiro city, one of the largest cities of the country, and the host of the 2016 Olympic Games. Anthropogenic interference in Guanabara Bay area started early in the XVI century, but environmental impacts escalated from 1930, when this region underwent an industrialization process. Herein we present an overview of the current environmental and sanitary conditions of Guanabara Bay, a consequence of all these decades of impacts. We will focus on microbial communities, how they may affect higher trophic levels of the aquatic community and also human health. The anthropogenic impacts in the bay are flagged by heavy eutrophication and by the emergence of pathogenic microorganisms that are either carried by domestic and/or hospital waste (e.g., virus, KPC-producing bacteria, and fecal coliforms), or that proliferate in such conditions (e.g., vibrios). Antibiotic resistance genes are commonly found in metagenomes of Guanabara Bay planktonic microorganisms. Furthermore, eutrophication results in recurrent algal blooms, with signs of a shift toward flagellated, mixotrophic groups, including several potentially harmful species. A recent large-scale fish kill episode, and a long trend decrease in fish stocks also reflects the bay's degraded water quality. Although pollution of Guanabara Bay is not a recent problem, the hosting of the 2016 Olympic Games propelled the government to launch a series of plans to restore the bay's water quality. If all plans are fully implemented, the restoration of Guanabara Bay and its shores may be one of the best legacies of the Olympic Games in Rio de Janeiro.
... Louis MARTIN, Jean-Marie FLEXOR et Jean-Louis VALENTIN Résumé - Le phénomène ockanique pacifi... more ... Louis MARTIN, Jean-Marie FLEXOR et Jean-Louis VALENTIN Résumé - Le phénomène ockanique pacifique ... of the dominant swell have occurred along the coast of Espirito Santo State during ... au contraire, en automne et en hiver, elles sont chaudes (fig., u). Moreira da Silva [2 ...
RESUMO Organismos da macrofauna bentônica são utilizados como indicadores ambientais por responde... more RESUMO Organismos da macrofauna bentônica são utilizados como indicadores ambientais por responderem a distúrbios naturais e antropogênicos. Este artigo tem como objetivo levantar informações sobre a macrofauna bentônica em estuários, manguezais e lagoas costeiras prioritárias para conservação no Brasil, comparar o conhecimento entre as regiões do país e direcionar futuros trabalhos. Foram encontrados 136 trabalhos publicados entre 1950 – 2010, realizados em 33 das 61 áreas prioritárias. As regiões mais estudadas são sudeste e sul, sendo que a Baía de Paranaguá e Lagoa dos Patos ABSTRACT Macrobenthic organisms are useful indicators of estuarine environmental status as they respond predictably to many kinds of natural and human-induced disturbances. The goal of the present review is to assess the state of knowledge about these communities on priority estuaries, mangroves and coastal lagoons considered as priorities for conservation in Brazil; to compare the knowledge among Brazilian ...
Ecotoxicology and environmental safety, Jan 5, 2018
The relationship between metal accumulation and feeding behavior of macrofauna species is a key c... more The relationship between metal accumulation and feeding behavior of macrofauna species is a key concept to understand the bioavailability of different metals in the marine environment. We examined and compared the concentrations of eight heavy metals (Cr, Zn, Pb, Ni, Cu, Cd, Co and V) in different feeding guilds of macrofauna species, from a data set including 68 sandy beaches along the Rio de Janeiro coast. For this purpose, macrofauna species were classified in five feeding guild categories: carnivorous, herbivorous, detritivorous, suspensivorous and filter feeders. The coast of Rio de Janeiro was divided into seven regions according to environmental characteristics and historical human activities. For each region, generalized linear models were adjusted to test for differences between feeding guild abundances. Redundancy Analysis was performed to explore the relationship among the feeding guilds composition and the environmental variables. We found high variability in abundance a...
Neotropical Ichthyology
The feeding ecology of five elasmobranch species was studied on the southern coast of Rio de Jane... more The feeding ecology of five elasmobranch species was studied on the southern coast of Rio de Janeiro, southwestern Atlantic Ocean. The specimens were caught with a trawl or bottom longline between January 2006 and August 2007. The diets of Psammobatis rutrum and Psammobatis extenta appeared to be basically carcino-benthophagous, with a very small niche width. Rioraja agassizii was basically carcino/ichthyo-benthophagous, also with a narrow niche, including teleost fish and shrimp, but in different proportions according to age and sex. Rhizoprionodon lalandii was ichthyophagous, not influenced by age or sex. The analyses of these species and Atlantoraja cyclophora indicated two trophic groups: one composed of the smaller rays, P. extenta and P. rutrum, which basically fed on small crustaceans, polychaetes and nematodes; and the other of R. lalandii and the larger rays R. agassizii and A. cyclophora, which preyed on teleost fish and brachyurans.
Environmental Pollution, 2016
We evaluated concentrations of eight heavy metals Cr, Zn, Pb, Ni, Cu, Cd, Co and V, in tissues of... more We evaluated concentrations of eight heavy metals Cr, Zn, Pb, Ni, Cu, Cd, Co and V, in tissues of representative macrofauna species from 68 sandy beaches from the coast of Rio de Janeiro state. The links between contamination levels and community descriptors such as diversity, evenness, density and biomass, were also investigated. Metal concentrations from macrofaunal tissues were compared to maximum permissible limits for human ingestion stipulated by the Brazilian regulatory agency (ANVISA). Generalized linear models (GLM's) were used to investigate the variability in macrofauna density, richness, eveness and biomass in the seven different regions. A non-metric multidimensional scaling analysis (n-MDS) was used to investigate the spatial pattern of heavy metal concentrations along the seven regions of Rio de Janeiro coast. Variation partitioning was applied to evaluate the variance in the community assemblage explained by the environmental variables and the heavy metal concentrations. Our data suggested high spatial variation in the concentration of heavy metals in macrofauna species from the beaches of Rio de Janeiro. This result highlighted a diffuse source of contamination along the coast. Most of the metals concentrations were under the limits established by ANVISA. The variability in community descriptors was related to morphodynamic variables, but not with metal contamination values, indicating the lack of direct relationships at the community level. Concentration levels of eight heavy metals in macrofauna species from 68 sandy beaches on Rio de Janeiro coast (Brazil) were spatially correlated with anthropogenic activities such as industrialization and urbanization.
Hydrobiologia, 2004
A bacterial dynamics study was conducted in the southwest Atlantic Ocean off the Brazilian coast ... more A bacterial dynamics study was conducted in the southwest Atlantic Ocean off the Brazilian coast from October to December 1998 with samples collected at the depth of chlorophyll a maximum. The bacteria were counted by flow cytometry with the SYTO13 DNA dye and bacterial activity was measured as carbon production by the uptake of 3 H-leucine. The samples were also analysed for basic hydrographical variables. Bacterial counts varied from 2.1 to 9.7 × 10 5 cells ml −1 and bacterial production varied from 4.6 to 126.6 ng C L −1 h −1. Spatial distribution of nitrate, chlorophyll a, bacterial abundance and bacterial activity showed areas of water fertilization in the oligotrophic Atlantic Ocean. Statistical analysis of data characterized the division of the area in two by latitude 19 • S. On the north fertilizations are related to river discharge and on the south to the input of nutrients from deep waters. Remobilisation of nutrients in those spots results among all in higher biological activity. However the relation between bacterial abundance and activity is top-down controlled characterizing most of the waters as oligotrophic. Eddies showed by bacterial data can probably sustain the fisheries resources for the whole area. The influence of gradients across eddies on biological activity and food chain structure should be an important question to be studied in oligotrophic oceans.
Ciencia E Cultura, Mar 1, 1987
Oecologia Brasiliensis, 1995
Oecologia Brasiliensis, 1999
Oceanologica Acta, 1980
Un traitement statistique par la méthode des composantes principales a été appliqué aux données d... more Un traitement statistique par la méthode des composantes principales a été appliqué aux données de plancton d'une station fixe située dans l'upwelling de Cabo Frio (Brésil). Les trois premières composantes expliquant 39 %de la variance totale du plancton ont fait l'objet d'une interprétation. Il s'agirait de: (1) l'alternance des masses d'eau au cours des phases successives de résurgence et subsidence; la communauté planctonique des eaux chaudes du Courant du Brésil et celle des eaux profondes sont mises en évidence par ce premier facteur, (2) la présence d'une thermocline, facteur favorable au démarrage des poussées algales, (3) l'influence du fond par remise en suspension des sédiments à la suite d'une forte turbulence ou de courants, donnant origine à une communauté algale composée d'espèces du microphytobenthos.
Revista Brasileira De Biologia, 1997
ABSTRACT RESUMO Organismos da macrofauna bentônica são utilizados como indicadores ambientais por... more ABSTRACT RESUMO Organismos da macrofauna bentônica são utilizados como indicadores ambientais por responderem a distúrbios naturais e antropogênicos. Este artigo tem como objetivo levantar informações sobre a macrofauna bentônica em estuários, manguezais e lagoas costeiras prioritárias para conservação no Brasil, comparar o conhecimento entre as regiões do país e direcionar futuros trabalhos. Foram encontrados 136 trabalhos publicados entre 1950 – 2010, realizados em 33 das 61 áreas prioritárias. As regiões mais estudadas são sudeste e sul, sendo que a Baía de Paranaguá e Lagoa dos Patos ABSTRACT Macrobenthic organisms are useful indicators of estuarine environmental status as they respond predictably to many kinds of natural and human-induced disturbances. The goal of the present review is to assess the state of knowledge about these communities on priority estuaries, mangroves and coastal lagoons considered as priorities for conservation in Brazil; to compare the knowledge among Brazilian regions, and to suggest the needs for further studies. We found 136 studies published during 1950-2010, at 33 of 61 priority areas. The most studied regions are southeast and south, Paranaguá Bay and Patos Lagoon concentrate the major number of publication in diverse subjects related to soft-bottoms macrobenthic communities. Community ecological aspects are the least studied subject, and development of further studies on this theme are crucial. Priority areas for conservation need immediate incentives to basic research, in special north and northeast regions. Mainly studies aiming to in-crease knowledge on local communities including taxonomic descriptions, community characterization and spatio-temporal dis-tribution of macrobenthic species. Considering the ecological and economic importance of estuarine systems, studies aiming the knowledge of the biodiversity should be increased to aid the implementation of monitoring, recovery and conservation programs.
Base de dados : REPIDISCA. Pesquisa : 153209 [Identificador único]. Referências encontradas : 1 [... more Base de dados : REPIDISCA. Pesquisa : 153209 [Identificador único]. Referências encontradas : 1 [refinar]. Mostrando: 1 .. 1 no formato [Detalhado]. página 1 de 1, 1 / 1, REPIDISCA, seleciona. para imprimir. Id: 153209. Autor: Valentin ...
Oecologia Brasiliensis, 1995
Frontiers in Microbiology, 2015
Guanabara Bay is the second largest bay in the coast of Brazil, with an area of 384 km 2. In its ... more Guanabara Bay is the second largest bay in the coast of Brazil, with an area of 384 km 2. In its surroundings live circa 16 million inhabitants, out of which 6 million live in Rio de Janeiro city, one of the largest cities of the country, and the host of the 2016 Olympic Games. Anthropogenic interference in Guanabara Bay area started early in the XVI century, but environmental impacts escalated from 1930, when this region underwent an industrialization process. Herein we present an overview of the current environmental and sanitary conditions of Guanabara Bay, a consequence of all these decades of impacts. We will focus on microbial communities, how they may affect higher trophic levels of the aquatic community and also human health. The anthropogenic impacts in the bay are flagged by heavy eutrophication and by the emergence of pathogenic microorganisms that are either carried by domestic and/or hospital waste (e.g., virus, KPC-producing bacteria, and fecal coliforms), or that proliferate in such conditions (e.g., vibrios). Antibiotic resistance genes are commonly found in metagenomes of Guanabara Bay planktonic microorganisms. Furthermore, eutrophication results in recurrent algal blooms, with signs of a shift toward flagellated, mixotrophic groups, including several potentially harmful species. A recent large-scale fish kill episode, and a long trend decrease in fish stocks also reflects the bay's degraded water quality. Although pollution of Guanabara Bay is not a recent problem, the hosting of the 2016 Olympic Games propelled the government to launch a series of plans to restore the bay's water quality. If all plans are fully implemented, the restoration of Guanabara Bay and its shores may be one of the best legacies of the Olympic Games in Rio de Janeiro.
... Louis MARTIN, Jean-Marie FLEXOR et Jean-Louis VALENTIN Résumé - Le phénomène ockanique pacifi... more ... Louis MARTIN, Jean-Marie FLEXOR et Jean-Louis VALENTIN Résumé - Le phénomène ockanique pacifique ... of the dominant swell have occurred along the coast of Espirito Santo State during ... au contraire, en automne et en hiver, elles sont chaudes (fig., u). Moreira da Silva [2 ...
RESUMO Organismos da macrofauna bentônica são utilizados como indicadores ambientais por responde... more RESUMO Organismos da macrofauna bentônica são utilizados como indicadores ambientais por responderem a distúrbios naturais e antropogênicos. Este artigo tem como objetivo levantar informações sobre a macrofauna bentônica em estuários, manguezais e lagoas costeiras prioritárias para conservação no Brasil, comparar o conhecimento entre as regiões do país e direcionar futuros trabalhos. Foram encontrados 136 trabalhos publicados entre 1950 – 2010, realizados em 33 das 61 áreas prioritárias. As regiões mais estudadas são sudeste e sul, sendo que a Baía de Paranaguá e Lagoa dos Patos ABSTRACT Macrobenthic organisms are useful indicators of estuarine environmental status as they respond predictably to many kinds of natural and human-induced disturbances. The goal of the present review is to assess the state of knowledge about these communities on priority estuaries, mangroves and coastal lagoons considered as priorities for conservation in Brazil; to compare the knowledge among Brazilian ...