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Ferruccio Maltagliati - One of the best experts on this subject based on the ideXlab platform.
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biodiversity and adaptive mechanisms in brackish water fauna
Marine Pollution Bulletin, 2000Co-Authors: Giuseppe Cognetti, Ferruccio MaltagliatiAbstract:A comparative analysis of estuaries, lagoons and coastal ponds focusing on population differentiation, and community structure is necessary to correctly address the issue of brackish water biology. Although the different biotopes all present similar features of environmental unpredictability and the common presence of the hypohalobic contingent (artenminimum), they each have their own characteristics, due to the evolution of peculiar balances in their relation to the sea on the one hand and inland waters on the other. In addition to euryhaline Species, locally adapted populations of Stenohaline Species typical of marine habitats, as well as some recently introduced Species, are also found. These Species have given rise to euryhaline populations, reaching their maximum development in an optimal site. This situation occurs between basins with essentially similar ecological features and probably depends both on the different degree of adaptability of many Species to a specific environmental parameter and the type of biocoenoses adjacent to the brackish basin. These populations possess genotypes allowing adaptation to brackish waters, which have resulted in the differentiation, through selection, of individuals capable of fine-grained perception of environmental unpredictability. Experimental works demonstrated the existence of genetically differentiated populations, or, ultimately, sibling Species complexes, in several brackish Species with broad geographical distribution and belonging to a wide range of taxonomic groups. The conceptions regarding the uniformity of brackish elements and the doubts concerning the existence of a specific brackish fauna come from the fact that attention generally focuses on Species in the traditional meaning of the term, that is to say at the macrosystematic level. Comparative analyses of very fine morpho-physiological changes and genetic analyses result in a rather different picture, leading to the conclusion that in brackish waters a given Species of marine origin often consists of many different forms at various levels of differentiation.
Giuseppe Cognetti - One of the best experts on this subject based on the ideXlab platform.
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biodiversity and adaptive mechanisms in brackish water fauna
Marine Pollution Bulletin, 2000Co-Authors: Giuseppe Cognetti, Ferruccio MaltagliatiAbstract:A comparative analysis of estuaries, lagoons and coastal ponds focusing on population differentiation, and community structure is necessary to correctly address the issue of brackish water biology. Although the different biotopes all present similar features of environmental unpredictability and the common presence of the hypohalobic contingent (artenminimum), they each have their own characteristics, due to the evolution of peculiar balances in their relation to the sea on the one hand and inland waters on the other. In addition to euryhaline Species, locally adapted populations of Stenohaline Species typical of marine habitats, as well as some recently introduced Species, are also found. These Species have given rise to euryhaline populations, reaching their maximum development in an optimal site. This situation occurs between basins with essentially similar ecological features and probably depends both on the different degree of adaptability of many Species to a specific environmental parameter and the type of biocoenoses adjacent to the brackish basin. These populations possess genotypes allowing adaptation to brackish waters, which have resulted in the differentiation, through selection, of individuals capable of fine-grained perception of environmental unpredictability. Experimental works demonstrated the existence of genetically differentiated populations, or, ultimately, sibling Species complexes, in several brackish Species with broad geographical distribution and belonging to a wide range of taxonomic groups. The conceptions regarding the uniformity of brackish elements and the doubts concerning the existence of a specific brackish fauna come from the fact that attention generally focuses on Species in the traditional meaning of the term, that is to say at the macrosystematic level. Comparative analyses of very fine morpho-physiological changes and genetic analyses result in a rather different picture, leading to the conclusion that in brackish waters a given Species of marine origin often consists of many different forms at various levels of differentiation.
Fernandes, Luiz F. Loureiro - One of the best experts on this subject based on the ideXlab platform.
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INTERANNUAL VARIABILITY IN TROPICAL ESTUARINE COPEPOD ASSEMBLAGES OFF NORTHEASTERN BRAZIL
CRUSTACEAN SOC, 2011Co-Authors: Magris, Rafael A., Pereira, Juliano B., Fernandes, Luiz F. LoureiroAbstract:We studied copepod assemblage variability among years, seasons, and tidal states in the Mucuri River estuary (Bahia State, Brazil). Zooplankton samples were collected seasonally through five years (2002-2006) at three sampling stations, one of which was sampled over a complete tidal cycle (two ebb and two flood tides). Temperature, salinity, river flux, and rainfall data were collected. Winter and summer represented dry and wet seasons, respectively. Copepod abundances ranged from 40 to 63% of the total zooplankton assemblage and comprised 46 taxa, among which, common estuarine Species such as Temora turbinata (first record for the studied area), Parvocalanus crassirostris, Acartia lilljeborgi, Oithona hebes were the most abundant (euryhaline Species). Interannual and seasonal variations were most marked in Stenohaline Species, e.g.. Notodiaptomus sp. and Thermocyclops minutus; density variations of euryhaline Species, which made up the majority of the abundant taxa, were most closely related to tides. Diversity and richness also followed an intertidal pattern of variation
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INTERANNUAL VARIABILITY IN TROPICAL ESTUARINE COPEPOD ASSEMBLAGES OFF NORTHEASTERN BRAZIL
CRUSTACEAN SOC, 2011Co-Authors: Magris, Rafael A., Pereira, Juliano B., Fernandes, Luiz F. LoureiroAbstract:We studied copepod assemblage variability among years, seasons, and tidal states in the Mucuri River estuary (Bahia State, Brazil). Zooplankton samples were collected seasonally through five years (2002-2006) at three sampling stations, one of which was sampled over a complete tidal cycle (two ebb and two flood tides). Temperature, salinity, river flux, and rainfall data were collected. Winter and summer represented dry and wet seasons, respectively. Copepod abundances ranged from 40 to 63% of the total zooplankton assemblage and comprised 46 taxa, among which, common estuarine Species such as Temora turbinata (first record for the studied area), Parvocalanus crassirostris, Acartia lilljeborgi, Oithona hebes were the most abundant (euryhaline Species). Interannual and seasonal variations were most marked in Stenohaline Species, e.g.. Notodiaptomus sp. and Thermocyclops minutus; density variations of euryhaline Species, which made up the majority of the abundant taxa, were most closely related to tides. Diversity and richness also followed an intertidal pattern of variation.Zooplankton Laboratory at the Federal University of Espirito Sant
Frederico P. Brandini - One of the best experts on this subject based on the ideXlab platform.
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Composição, abundância e distribuição espacial do zooplâncton no complexo estuarino de Paranaguá durante o inverno de 1993 e o verão de 1994 Zooplankton composition, abundance and spatial distribution in the estuarine complex of Paranaguá during winter 1993 and summer 1994
Universidade de São Paulo, 1998Co-Authors: Rubens M. Lopes, Rosinei Do Vale, Frederico P. BrandiniAbstract:A estrutura das associações zooplanctônicas do complexo estuarino de Paranaguá foi estudada no inverno de 1993 e no verão de 1994. Copépodes dos gêneros Acartia, Paracalanus, Parvocalanus, Temora, Pseudodiaptomus, Oithona e Euterpina foram dominantes, atingindo até cerca de 90% da densidade total. A única espécie que ocorreu preferencialmente em salinidades inferiores a 15 foi o calanóide Pseudodiaptomus richardi, que representa o principal componente do holoplncton nos setores oligohalinos. Acartia tonsa e Oithona oswaldocruzi predominaram nos trechos intermediários, associadas a outras espécies estuarino-marinhas que suportam maiores variações de salinidade, como Acartia lilljeborgi, Pseudodiaptomus acutus e Oithona hebes. Espécies marinho-eurihalinas como Temora turbinata, Paraca/anus quasimodo, Oithona simplex e Euterpina acutifrons ocorreram em salinidades tão baixas quanto 15, mas foram mais abundantes na área externa influenciada pela água costeira. Várias espécies marinho-estenohalinas, associadas principalmente às águas quentes da Corrente do Brasil, foram registradas no setor euhalino. Outros grupos zooplanctônicos numericamente importantes foram os tintinineos, apendiculárias, cladóceros e alguns representantes do meroplncton, como as larvas de poliquetas e decápodes. Os máximos de abundncia do zooplncton (até cerca de 82000 org.m-3) ocorreram nos setores intermediários, em salinidades variando entre 15 e 30, coincidindo aproximadamente com o padrão de distribuição da biomassa fitoplanctônica.Zooplankton community structure was investigated in the estuarine complex of Paranaguá (Southern Brazil) during July 1993 (winter) and February-March 1994 (summer). Copepods belonging to the genera Acartia, Paracalanus, Parvocalanus, Pseudodiaptomus, Temora, Oithona and Euterpina dominated the zooplankton associations, attaining up to 90% of total densities. Pseudodiaptomus richardi was the dominant estuarine copepod in oligohaline stretches with salinities below 15. Estuarine marine Species such as Acartia tonsa, Oithona hebes and Oithona oswaldocruzi reached high densities in salinities ranging from 17 to 25. Other abundant estuarine marine Species including Acartia lilljeborgi and Pseudodiaptomus acutus occurred in a broader salinity range. Marine euryhaline copepods were found in salinities as low as 15, but were usually more abundant in areas under the influence of coastal waters. Several marine Stenohaline Species associated with the warm waters of the Brazil Current were recorded in the euhaline areas. Other important zooplanktonic groups in this estuarine complex were tintinnids, appendicularians, cladocerans and meroplanktonic larvae of polychaetes and decapods. Density maxima (up to 82400 org.m-³) were found in the intermediate stretches - in salinities varying from 15 to 30 - corresponding approximately to the distributional pattern of phytoplankton biomass
Brandini, Frederico P. - One of the best experts on this subject based on the ideXlab platform.
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Composição, abundância e distribuição espacial do zooplâncton no complexo estuarino de Paranaguá durante o inverno de 1993 e o verão de 1994
Universidade de São Paulo. Instituto Oceanográfico, 1998Co-Authors: Lopes, Rubens M., Rosinei Do Vale, Brandini, Frederico P.Abstract:Zooplankton community structure was investigated in the estuarine complex of Paranaguá (Southern Brazil) during July 1993 (winter) and February-March 1994 (summer). Copepods belonging to the genera Acartia, Paracalanus, Parvocalanus, Pseudodiaptomus, Temora, Oithona and Euterpina dominated the zooplankton associations, attaining up to 90% of total densities. Pseudodiaptomus richardi was the dominant estuarine copepod in oligohaline stretches with salinities below 15. Estuarine marine Species such as Acartia tonsa, Oithona hebes and Oithona oswaldocruzi reached high densities in salinities ranging from 17 to 25. Other abundant estuarine marine Species including Acartia lilljeborgi and Pseudodiaptomus acutus occurred in a broader salinity range. Marine euryhaline copepods were found in salinities as low as 15, but were usually more abundant in areas under the influence of coastal waters. Several marine Stenohaline Species associated with the warm waters of the Brazil Current were recorded in the euhaline areas. Other important zooplanktonic groups in this estuarine complex were tintinnids, appendicularians, cladocerans and meroplanktonic larvae of polychaetes and decapods. Density maxima (up to 82400 org.m-³) were found in the intermediate stretches - in salinities varying from 15 to 30 - corresponding approximately to the distributional pattern of phytoplankton biomass.A estrutura das associações zooplanctônicas do complexo estuarino de Paranaguá foi estudada no inverno de 1993 e no verão de 1994. Copépodes dos gêneros Acartia, Paracalanus, Parvocalanus, Temora, Pseudodiaptomus, Oithona e Euterpina foram dominantes, atingindo até cerca de 90% da densidade total. A única espécie que ocorreu preferencialmente em salinidades inferiores a 15 foi o calanóide Pseudodiaptomus richardi, que representa o principal componente do holoplncton nos setores oligohalinos. Acartia tonsa e Oithona oswaldocruzi predominaram nos trechos intermediários, associadas a outras espécies estuarino-marinhas que suportam maiores variações de salinidade, como Acartia lilljeborgi, Pseudodiaptomus acutus e Oithona hebes. Espécies marinho-eurihalinas como Temora turbinata, Paraca/anus quasimodo, Oithona simplex e Euterpina acutifrons ocorreram em salinidades tão baixas quanto 15, mas foram mais abundantes na área externa influenciada pela água costeira. Várias espécies marinho-estenohalinas, associadas principalmente às águas quentes da Corrente do Brasil, foram registradas no setor euhalino. Outros grupos zooplanctônicos numericamente importantes foram os tintinineos, apendiculárias, cladóceros e alguns representantes do meroplncton, como as larvas de poliquetas e decápodes. Os máximos de abundncia do zooplncton (até cerca de 82000 org.m-3) ocorreram nos setores intermediários, em salinidades variando entre 15 e 30, coincidindo aproximadamente com o padrão de distribuição da biomassa fitoplanctônica