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Vertical patterns of ichthyoplankton at the interface between a temperate estuary and adjacent coastal waters: Seasonal relation to diel and tidal cycles

Primo, Ana Lígia; Azeiteiro, Ulisses M.; Marques, Sónia C.; Ré, Pedro; Pardal, M. A.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
56.11%
Vertical distribution and migration pattern of ichthyoplankton assemblage in the Mondego estuary were investigated in relation to diel and tidal cycle. Summer and winter communities were sampled, at surface and bottom, over a diel cycle during spring and neap tides at a fixed station at the mouth of the estuary. Summer presented higher larvae density mainly of Pomatoschistus spp., Gobius niger and Parablennius pilicornis. Main species in winter assemblages were Pomatoschistus spp. and Sardina pilchardus. There were no differences between depth stratums across diel or tide cycle. Nevertheless, main species larval densities showed significant periodic variation associated with tide (M2) and diel (K1) cycles presenting generally, higher density at night and around low tide. Conversely, vertical patterns observed could not be related with diel or tidal cycle. Tough, main species presented some extent of vertical migration. Vertical patterns observed appear to be related to seasonal stratification and river flow, increasing amplitude during periods of less stratification and lower water currents. Present study provides a better understanding of ichthyoplankton vertical movement patterns and of small scale dynamics at the interface of two coastal European systems.

Distribuição e abundância de larvas de Phosichtyidae e condições oceanográficas na região entre o cabo de São Tomé (RJ) e a ilha de São Sebastião (SP); Distribution and abundance of larval Phosichthyidae and oceanographic conditions in the region between São Tomé cape (RJ) and São Sebastião island (SP)

Goçalo, Cassia Gongora
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 12/09/2008 PT
Relevância na Pesquisa
56.11%
A distribuição horizontal e vertical das larvas de peixes mesopelágicos de Phosichthyidae foi descrita a partir de dados amostrados desde a superfície até 200 m de profundidade, e em 5 estratos na coluna de água. As coletas foram realizadas no verão e inverno de 2002, em radiais perpendiculares à costa Sudeste do Brasil, entre o cabo de São Tomé (RJ) e a ilha de São Sebastião (SP). A abundância das larvas (larvas.m²) foi estimada para o material amostrado pela rede Bongô (333 cm) e a densidade (larvas.m³) para a Multi Plankton Sampler (300 cm). No total foram coletadas 538 larvas de Phosichthyidae no verão e 146 no inverno. Duas espécies foram identificadas, Pollichthys mauli e Vinciguerria nimbaria, ambas apresentaram-se distribuídas, preferencialmente, na região oceânica da área de estudo com maiores densidades entre 60 e 80 m de profundidade, onde a temperatura e a salinidade foram superiores a 20°C e 36, respectivamente, estando diretamente relacionados à massa de Água Tropical, transportada pela Corrente do Brasil. Todas as fases de desenvolvimento larval foram capturadas, entretanto, a maioria das larvas estava em pós-flexão da notocorda. Em relação à variação diária, as larvas foram mais abundantes durante a noite.; Horizontal and vertical distribution of mesopelagic Phosichthyidae fish larvae was described based on data sampled collected from the surface up to 200 m depth...

Influência das massas de água sobre a distribuição das larvas de Myctophidae (Teleostei) e análise de aspectos biológicos de Myctophum affine na costa sudeste do Brasil (22ºS-25ºS); Distribution of Myctophidae (Teleostei) larvae under the influence of water masses and biological aspects of Myctophum affine in the southeast Brazilian waters (22°S-25°S)

Namiki, Claudia Akemi Pereira
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 06/08/2013 PT
Relevância na Pesquisa
56.2%
Com o objetivo de investigar a influência das massas de água sobre a distribuição horizontal e vertical das larvas de Myctophidae e de analisar a condição nutricional, o crescimento e a mortalidade de Myctophum affine, amostragens foram realizadas através de arrastos oblíquos (rede bongô) e estratificados (rede Multinet), em águas do sudeste brasileiro, desde a costa até o talude, entre cabo de São Tomé (RJ) e ilha de São Sebastião (SP). A intrusão da Água Central do Atlântico Sul diminuiu a extensão da Água Tropical (AT) sobre a plataforma. Como as larvas de Myctophidae foram associadas à AT, esse processo reduziu a ocorrência dessas larvas na plataforma. As espécies apresentaram diferentes padrões de distribuição vertical e horizontal, ressaltando a importância da identificação em nível taxonômico específico para a obtenção de um padrão de distribuição mais refinado. A análise histológica dos hepatócitos de Myctophum affine, a espécie mais abundante, evidenciou que a maioria das larvas estava em boa condição nutricional; apenas aquelas nos estágios menos avançados apresentavam sinais de inanição severa. Sua taxa de crescimento média (0,33 mm/dia) foi considerada intermediária entre os mictofídeos e a duração de seu período larval uma das menores. A taxa de mortalidade (11...

Padrão de distribuição vertical dos foraminíferos bentônicos vivos no talude continental do setor norte da Bacia de Campos, margem sudeste brasileira: resposta da fauna ao aporte de matéria orgânica; Living benthic foraminifera vertical distribution on the continental slope on the northern sector of the Campos Basin, Southeastern Brazilian margin: fauna response to organic matter input

Yamamoto, Naira Tieme
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 20/02/2014 PT
Relevância na Pesquisa
66.17%
Amostras de sedimento foram coletadas no talude superior e médio da Bacia de Campos para avaliar a quantidade e qualidade da matéria orgânica (MO) disponíveis no ambiente. A partir de dados geoquímicos, sedimentológicos (tamanho médio de grão e razão silte/argila), e microfaunísticos foi possível identificar diferenças no aporte de MO no talude. O talude superior apresentou valores maiores de conteúdo de carbono orgânico (COT) e lipídeos, elevados valores de densidade, baixos valores de diversidade, riqueza, equitatividade, ALD10, e perfil vertical com densidades maiores, predomínio de espécies epifaunais e/ou infaunais rasos, indicando ambiente com maior produtividade primária sobre maior influência de pulsos de fitodetrito, decorrente da influência do Vórtice de Vitória transportando nutrientes para o mar profundo. Já o talude médio, apresentou menores valores de COT, lipídeos e densidade, maiores valores de diversidade, riqueza, equitatividade, ALD10, predomínio de espécies aglutinantes, indicando condições com menor aporte de nutrientes lábeis. Pelos dados microfaunísticos obtidos, o modelo TROX não pode ser aplicado no talude da Bacia de Campos como avaliador de condições tróficas possivelmente pela não inclusão de fatores como disponibilidade de MO lábil...

Bromeliad architectural complexity and vertical distribution predict spider abundance and richness

Goncalves-Souza, Thiago; Almeida-Neto, Mario; Romero, Gustavo Q.
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica Formato: 476-484
ENG
Relevância na Pesquisa
56.08%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 06/59410-0; Habitat complexity is a main predictor of the distribution of arthropods on vegetation. However, it remains poorly known whether plant architecture and fine-scale spatial distribution affect the species richness and composition of associated arthropod guilds. In this study, we extensively sampled bromeliad species with a variety of rosette architectures in a megadiversity region. The aims were to investigate whether (i) possible differences in spider species composition among bromeliad species are related to the distinct architectures of the plants, and (ii) bromeliad architectural complexity (an intrinsic feature) and vertical distribution (an extrinsic feature) are good predictors of spider abundance and richness. Contrary to our expectations, spider species composition did not vary significantly among bromeliad species with different architectures. We found a positive effect of the mean number of leaves on spider abundance and species richness, but it occurred indirectly through spider abundance; factoring out the indirect effect revealed a negative effect of leaf number on species richness. Bromeliad species with wider vertical distributions harboured more spider species. Our results suggest that the dominance of a few spider species and reduced space for orb-web spiders to attach their webs are the main explanations for lower spider richness on bromeliad species with higher architectural complexity. Our findings highlight the importance of both intrinsic and extrinsic plant features as co-determinants of predator arthropod diversity.

Vertical distribution by demographic groups of ghost crab Ocypode quadrata (Crustacea: Brachyura)

Correa, Michele O. D. A.; Andrade, Luciana S.; Costa, Rogerio C.; Castilho, Antonio L.; Bertini, Giovana; Fransozo, Adilson
Fonte: De Gruyter Open Ltd Publicador: De Gruyter Open Ltd
Tipo: Artigo de Revista Científica Formato: 905-915
ENG
Relevância na Pesquisa
56.17%
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); The ghost crab Ocypode quadrata plays an important role in energy transfer between trophic levels, and has been widely used in evaluations of impacted environments. In order to provide data on the biology of this potential bioindicator species, the population structure and vertical distribution of individuals were studied on two beaches in southeastern Brazil. Each beach was divided into quadrants of 1000 m(2) with boundaries of upper, middle and lower levels in relation to the waterline. Collected monthly by active searching through one year, the specimens of O. quadrata were sexed, measured for carapace width, and returned to the beach. Of the total of 1904 specimens collected, the largest proportion (46.2%) were males, followed by 31.4% juveniles. The vertical distribution of the ghost crabs differed among age groups: males mostly occupied the middle and upper levels; adult females, ovigerous or not, were more abundant in the lower level; and juveniles were evenly distributed in all levels, with a slight tendency toward the middle. The sex ratio favored males in a few months of the year and in the larger size classes. The abundance of O. quadrata is limited by low temperatures...

Vertical distribution and trophic structure of the macrozooplankton in a shallow temperate estuary (Ria de Aveiro, Portugal)

Morgado, F. M.; Pastorinho, M. R.; Quintaneiro, C.; Re, P.
Fonte: Consejo Superior de Investigaciones Científicas Publicador: Consejo Superior de Investigaciones Científicas
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
56.07%
The zooplankton of the lower part of Canal de Mira (Ria de Aveiro) was sampled during one lunar month. The sampling programme consisted of nine 25 hour fixed-cycles, separated weekly. In each cycle, samples were collected every two hours at three depths (surface, mid-water and above the bottom) with a 500 µm mesh net. The overall effect of the tidal phase was analyzed, taking into account the day and depth of the vertical position of the organisms through a 3-way analysis of variance (ANOVA). The zooplankton densities were, in general, higher at the surface during the night and near the bottom during the day, mainly at spring tide. The variation in the number of species followed a similar pattern to that observed for abundance. Significant differences (p<0.01) between diel and tidal phases were observed. Interaction between phase of the day and depth was also significant (p<0.05), with higher organism densities observed during night periods near the bottom. From a trophic point of view the zooplankton community of Canal de Mira was mainly composed of carnivorous and omnivorous species. Carnivores were significantly more abundant around the new and full moon (p<0.001), the omnivores at the new moon (p<0.001) and the herbivores and detritivores at the first quarter of the moon cycles (p<0.001). The density of carnivores was significantly higher at the surface at night and near the bottom during the day (p<0.05). Significant differences in the abundance of omnivores were observed between phases of the day and between depths...

Composition, species richness and patterns of nycthemeral vertical distribution of planktonic cladocereans in a black water Amazonian lake

Ghidini,André Ricardo; Santos-Silva,Edinaldo Nelson dos
Fonte: Sociedade Brasileira de Carcinologia Publicador: Sociedade Brasileira de Carcinologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2011 EN
Relevância na Pesquisa
56.08%
The aim of this study was to identify patterns of vertical distribution of planktonic cladocerean populations throughout the diel cycle, during the low and high water periods, and its ecological implications for a black water Amazonian lake. Tupé Lake is a black water lake located near the Brazilian city of Manaus. A channel links the lake with the Negro River and its flood pulse. This study was performed in a low-water period (November 2005) and in a high-water period (June 2006). Samples were taken on a 24-hour cycle, every 4 hours and at each meter of the water column, using a Schindler-Patalas trap equipped with a 55µm size mesh. A total of 16 species were registered during the low water period, wherein Bosminopsis deitersi, Moina minuta, and Ceriodaphnia cornuta were the most abundant species. B. deitersi migrated to the bottom during the afternoon, while M. minuta, Moina reticulata, and Holopedium amazonicum remained at the bottom for the entire diel cycle. During the high-water period, a total of 18 species were observed, and B. deitersi, C. cornuta, and Diaphanosoma polyspina were the most abundant species. During both sampling periods, no pattern was detected for C. cornuta. Generally, vertical patterns of distribution were less evident in the high water period...

Vertical distribution of benthic marine organisms on rocky coasts of the Fernando de Noronha Archipelago (Brazil)

Eston,Verena Rapp de; Migotto,Alvaro Esteves; Oliveira Filho,Eurico Cabral de; Rodrigues,Sergio de Almeida; Freitas,Jose Carlos de
Fonte: Instituto Oceanográfico da Universidade de São Paulo Publicador: Instituto Oceanográfico da Universidade de São Paulo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/1986 EN
Relevância na Pesquisa
55.98%
Qualitative samples of flora and fauna were collected in several points, from the supralittoral fringe down to 30 m, using mainly aqualungs. Species distribution and abundance were determined along four transects, up to 200 m long, in selected places. Samples were taken from 25 x 25 cm quadrats positioned at fixed intervals along the transects down to a variable depth, depending on algal percentage cover and their substrate. The intertidal zone was populated essentially by molluscs. The subtidal was covered predominantly by macroalgae. Montastrea cavernosa, Siderastrea stellata and Mussismillia hispida were the only animal species with a significant percentage cover within the quadrats. Dictyopteris justii, D. plagiograma, Dictyota cervicornis, D. linearis, D. mertensii, Sargassum platycarpum, Sargassum sp, and Stypopodium zonale were the plants with the highest biomass and/or percentage cover, along with Amphiroa fragilissima, Caulerpa verticillata, and crustose corallines. The scarcity of sea urchins, along with the dominance of algae known to produce chemical feeding deterrents or to have a calcareous nature, points towards a strong pressure by predators, with fishes probably playing a key role in the maintenance of the structure of this subtidal community.

Arbuscular mycorrhizal fungi in saline soils: vertical distribution at different soil depth

Becerra,Alejandra; Bartoloni,Norberto; Cofré,Noelia; Soteras,Florencia; Cabello,Marta
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2014 EN
Relevância na Pesquisa
56.03%
Arbuscular mycorrhizal fungi (AMF) colonize land plants in every ecosystem, even extreme conditions such as saline soils. In the present work we report for the first time the mycorrhizal status and the vertical fungal distribution of AMF spores present in the rhizospheric soil samples of four species of Chenopodiaceae (Allenrolfea patagonica, Atriplex argentina, Heterostachys ritteriana and Suaeda divaricata) at five different depths in two saline of central Argentina. Roots showed medium, low or no colonization (0-50%). Nineteen morphologically distinctive AMF species were recovered. The number of AMF spores ranged between 3 and 1162 per 100 g dry soil, and AMF spore number decreased as depth increased at both sites. The highest spore number was recorded in the upper soil depth (0-10 cm) and in S. divaricata. Depending of the host plant, some AMF species sporulated mainly in the deep soil layers (Glomus magnicaule in Allenrolfea patagonica, Septoglomus aff. constrictum in Atriplex argentina), others mainly in the top layers (G. brohultti in Atriplex argentina and Septoglomus aff. constrictum in Allenrolfea patagonica). Although the low percentages of colonization or lack of it, our results show a moderate diversity of AMF associated to the species of Chenopodiaceae investigated in this study. The taxonomical diversity reveals that AMF are adapted to extreme environmental conditions from saline soils of central Argentina.

Effects of net cages on the vertical distribution of zooplankton in a semi-arid reservoir, northeastern Brazil

Freitas,Glécia Trinta de Paula; Crispim,Maria Cristina; Melo Júnior,Hênio do Nascimento de
Fonte: Associação Brasileira de Limnologia Publicador: Associação Brasileira de Limnologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2012 EN
Relevância na Pesquisa
66.17%
AIM: Carneiro reservoir is an aquatic environment used for net cage aquaculture activities, located in the semi-arid region of northeastern Brazil. Vertical distribution was evaluated in order to determine the effects of organic enrichment induced by aquaculture on zooplankton movements. METHODS: three replicate samples were collected during midday and midnight at each of three depths along the water column (i.e. surface: 0 m; middle: 2 m and bottom: 4 m) at two sites (near and far from the net cages). Samples were collected using a 3 L volume capacity Van Dorn bottle. The collected individuals were preserved in a 4% formaldehyde solution saturated with sugar and, later, identified and counted on a Sedgwick-Rafter chamber under a microscope, considering a minimum of 100 individuals per subsample. RESULTS: higher species richness and density were observed at the N station (nearby the net cages) compared to the F station (distant from the net cages). With few exceptions, Rotifer species did not exhibit typical vertical migration patterns, concentrating at bottom depths during daytime and at intermediate depths during nighttime. Brachionus dolabratus and Hexarthra mira were the only species to show reverse vertical migration at the N station...

Driving forces of the diel distribution of phytoplankton functional groups in a shallow tropical lake (Lake Monte Alegre, Southeast Brazil); Fatores direcionadores da distribuição nictemeral de grupos funcionais fitoplanctônicos de um lago brasileiro raso e tropical

RANGEL, LM.; SILVA, LHS.; ARCIFA, MS.; PERTICARRARI, A.
Fonte: Instituto Internacional de Ecologia Publicador: Instituto Internacional de Ecologia
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
56.2%
Phytoplankton vertical and diel dynamics in a small shallow lake (Lake Monte Alegre, Ribeirão Preto, state of São Paulo) were investigated in two climatological periods: July 2001 (cool-dry season) and March 2002 (warm-rainy season). Monte Alegre is a eutrophic reservoir, with a warm polymictic discontinuous circulation pattern. The lake was thermally stratified in both periods, although dissolved oxygen varied less in the cool-dry period. Phytoplankton biomass was higher in the warm-rainy season and the vertical distribution was stratified in both seasons. Flagellate groups (Lm, Y, W1 and W2) and functional groups typical of shallow eutrophic environments (J, X1 and Sn) were important throughout the study period. The lake's thermal pattern strongly influenced the vertical distribution of the phytoplankton community in both periods. Biomass, functional groups and size classes of phytoplankton also were determined by the presence of more efficient herbivores in the lake, especially during the cool-dry period when phytoplankton biomass decreased.; As dinâmicas vertical e nictemeral do fitoplâncton de um lago pequeno e raso (Lago Monte Alegre, Ribeirão Preto, SP) foram investigadas em dois períodos climatológicos: julho/2001 (estação fria-seca) e março/2002 (estação quente-chuvosa). O lago esteve estratificado termicamente nos dois períodos de estudo...

Driving forces of the diel distribution of phytoplankton functional groups in a shallow tropical lake (Lake Monte Alegre, Southeast Brazil)

Rangel,LM.; Silva,LHS.; Arcifa,MS.; Perticarrari,A.
Fonte: Instituto Internacional de Ecologia Publicador: Instituto Internacional de Ecologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2009 EN
Relevância na Pesquisa
56.11%
Phytoplankton vertical and diel dynamics in a small shallow lake (Lake Monte Alegre, Ribeirão Preto, state of São Paulo) were investigated in two climatological periods: July 2001 (cool-dry season) and March 2002 (warm-rainy season). Monte Alegre is a eutrophic reservoir, with a warm polymictic discontinuous circulation pattern. The lake was thermally stratified in both periods, although dissolved oxygen varied less in the cool-dry period. Phytoplankton biomass was higher in the warm-rainy season and the vertical distribution was stratified in both seasons. Flagellate groups (Lm, Y, W1 and W2) and functional groups typical of shallow eutrophic environments (J, X1 and Sn) were important throughout the study period. The lake's thermal pattern strongly influenced the vertical distribution of the phytoplankton community in both periods. Biomass, functional groups and size classes of phytoplankton also were determined by the presence of more efficient herbivores in the lake, especially during the cool-dry period when phytoplankton biomass decreased.

Vertical distribution of early developmental stages in two coexisting clupeoid species, Sardinella aurita and Engraulis encrasicolus

Sabatés, Ana; Zaragoza, Nuria; Grau, Claudia; Salat, Jordi
Fonte: Inter Research Publicador: Inter Research
Tipo: Artículo Formato: 484641 bytes; application/pdf
ENG
Relevância na Pesquisa
66.14%
12 pages, 8 figures, 4 tables.-- Full-text version available Open Access at: http://www.icm.csic.es/files/oce/almacen/papers/AR-2008-17.pdf; In recent years a northward expansion of Sardinella aurita has been reported in the western Mediterranean. Considering the coexistence of its larvae with those of the dominant species Engraulis encrasicolus, the present study was conducted to compare their vertical distributions in 2 areas off the Catalan coast with different vertical environmental conditions. During summer, the water column was stratified with a deep chlorophyll maximum (DCM) beneath the pycnocline. However, the southern area, under the influence of the Ebro River, was characterized by a secondary surface chlorophyll maximum. Vertical distribution of larval food, nauplii and copepodites showed good agreement with the high chlorophyll layers. In the earliest stages of development, larvae of both species remained in the upper levels. From 6 mm standard length on they developed a day/night migratory behaviour to search for food during the day (feeding period). Therefore, in the south, where the abundance of potential food in the upper layers was relatively high, larvae of both species remained in the upper levels during the day. However...

Chaetognath spatial distribution and how egg-carrying affects the vertical distribution of Sagitta tasmanica off southern Chile; Distribución espacial de los quetognatos y cómo la portación de huevos afecta la distribución vertical de Sagitta tasmanica en el sur de Chile

Villenas, Francisco; Palma, Sergio; Soto, Daniela
Fonte: Consejo Superior de Investigaciones Científicas (España) Publicador: Consejo Superior de Investigaciones Científicas (España)
Tipo: Artículo Formato: 1946509 bytes; application/pdf
ENG
Relevância na Pesquisa
66.19%
10 pages, 6 figures.; [EN] Six chaetognath species were determined, all for the first time, in the inner waters between Reloncaví Fjord and Boca del Guafo, Chile. Sagitta tasmanica (85.3%) and Eukrohnia hamata (5.8%) were dominant. Sagitta minima was collected for the first time in the southern channel and fjord region. The largest chaetognath aggregations were found around the Desertores Islands, which create a geographic barrier between two microbasins (north and south) with different oceanographic characteristics. S. decipiens was distributed mostly in the surface layer (0-50 m), whereas E. hamata, S. chilensis, S. minima, and S. enflata were found in deeper waters (50-200 m). The vertical distribution of S. tasmanica was homogeneous; mature, egg-carrying individuals were found at greater depths than those without eggs.; [ES] Se determinó la presencia de seis especies de quetognatos, todas ellas registradas por primera vez en aguas interiores comprendidas entre el fiordo Reloncaví y la boca del Guafo, Chile. Las especies dominantes fueron Sagitta tasmanica (85,3%) y Eukrohnia hamata (5,8%), mientras que S. minima se colectó por primera vez en el ecosistema de canales y fiordos australes. Las mayores agregaciones de quetognatos se determinaron alrededor de las islas Desertores...

Vertical distribution of benthic marine organisms on rocky coasts of the Fernando de Noronha archipelago (Brazil)

Eston, Verena Rapp de; Migotto, Alvaro Esteves; Oliveira Filho, Eurico Cabral de; Rodrigues, Sergio de Almeida; Freitas, Jose Carlos de
Fonte: Universidade de São Paulo. Instituto Oceanográfico Publicador: Universidade de São Paulo. Instituto Oceanográfico
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; Formato: application/pdf
Publicado em 01/01/1986 ENG
Relevância na Pesquisa
56.06%
Qualitative samples of flora and fauna were collected in several points, from the supralittoral fringe down to 30 m, using mainly aqualungs. Species distribution and abundance were determined along four transects, up to 200 m long, in selected places. Samples were taken from 25 x 25 cm quadrats positioned at fixed intervals along the transects down to a variable depth, depending on algal percentage cover and their substrate. The intertidal zone was populated essentially by molluscs. The subtidal was covered predominantly by macroalgae. Montastrea cavernosa, Siderastrea stellata and Mussismillia hispida were the only animal species with a significant percentage cover within the quadrats. Dictyopteris justii, D. plagiograma, Dictyota cervicornis, D. linearis, D. mertensii, Sargassum platycarpum, Sargassum sp, and Stypopodium zonale were the plants with the highest biomass and/or percentage cover, along with Amphiroa fragilissima, Caulerpa verticillata, and crustose corallines. The scarcity of sea urchins, along with the dominance of algae known to produce chemical feeding deterrents or to have a calcareous nature, points towards a strong pressure by predators, with fishes probably playing a key role in the maintenance of the structure of this subtidal community.

Distribuição vertical e sazonal de Anopheles (Kerteszia) em Ilha Comprida, SP; Vertical and seasonal distribution of Anopheles (Kerteszia) in Ilha Comprida, Southeastern Brazil

Ueno, Helene Mariko; Forattini, Oswaldo Paulo; Kakitani, Ina
Fonte: Universidade de São Paulo. Faculdade de Saúde Pública Publicador: Universidade de São Paulo. Faculdade de Saúde Pública
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf
Publicado em 01/04/2007 POR
Relevância na Pesquisa
56.14%
OBJETIVO: Anopheles bellator e An. cruzii são vetores da malária-bromélia, característicos de áreas preservadas. O objetivo do estudo foi analisar a distribuição sazonal e vertical desses anofelinos, visando contribuir para a avaliação do risco de transmissão desse agravo. MÉTODOS: No município de Ilha Comprida, SP, foram instaladas armadilhas luminosas tipo CDC iscadas com gelo seco, das 17 às 20h, a um, seis e 12m do solo, quinzenalmente, de setembro de 2001 a setembro de 2002. A relação da densidade desses anofelinos com o clima foi avaliada pelo coeficiente de Spearman e suas densidades entre os estratos foram comparadas pelo teste não paramétrico de Mann-Whitney. RESULTADOS: Do total de 55.226 mosquitos, 1.341 eram An. bellator (2,4% do total de Culicidae), sendo capturados 278 indivíduos próximo ao solo, 261 a seis metros e 802 na copa (12 m). Na mesma ordem, foram capturados 452, 1.032 e 4.420 adultos de An. cruzii, totalizando 5.904 mosquitos desta espécie (10,7%). Houve correlação positiva entre a densidade das duas espécies com a temperatura máxima, e entre An. bellator e amplitude térmica diária. As densidades das duas espécies foram maiores na copa. Nos três estratos, An. cruzii predominou sobre An. bellator. CONCLUSÕES: Confirmou-se o comportamento acrodendrófilo dessas espécies...

The vertical distribution and abundance of gastropods and bivalves from rocky beaches of Cuastecomate Bay, Jalisco. México

Esqueda,M. C; Ríos-Jara,E; Michel-Morfín,J. E; Landa-Jaime,V
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2000 EN
Relevância na Pesquisa
66.03%
The vertical distribution and abundance of conspicuous gastropod and bivalve species were studied at five rocky beaches in Cuastecomate Bay, Jalisco. Sampling was done from September, 1993 through March, 1994 with 0.75 m2 quadrants placed along replicate transect lines (10 m long) in the supralittoral and mesolittoral (upper, middle and lower intertidal) zones. A total of 6 643 mollusks were collected. Gastropods dominated the samples (6 272 individuals, 44 species); the bivalves were less abundant and diverse (371 individuals, five species). Seventeen species comprised 89.8% of all individuals collected. The gastropods Nodilittorina aspera and Nerita scabricosta were the most abundant with 637.8 and 71.43 individuals/m2, respectively. The most abundant bivalves were Brachidontes adamsianus and Chloromytilus palliopunctatus with 60.7 and 61.3 individuals/m2 respectively. The abundance of gastropods decreased from the supralittoral to the lower tidal zones while the number of species increased in the same direction. The number of species of bivalves also increased from the supralittoral to the lower intertidal zone; the abundance of individuals was higher at the middle intertidal zone. Affinities between groups of species among sampling stations were identified by computing Pearson’s correlation coefficient using abundance values (ind./m2) and Jaccard's dissimilarity index using species presence or absence in the lower intertidal zone. Affinity among stations was not dependent upon their vicinity but on the high dominance of few species...

Spatial and temporal variations of meiofaunal communities from the western sector of the Gulf of Batabanó, Cuba: III. Vertical distribution

Armenteros,M; Williams,J. P; Creagh,B; Capetillo,N
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2008 EN
Relevância na Pesquisa
66.17%
The vertical distribution of meiofauna within subtidal sediments was studied in four stations pertaining to mangrove or muddy flats habitats. In 2003, replicated samples were taken in dry (February) and wet (July) seasons at the Bacunagua Inlet, southwestern coast of Cuba. The abundance and number of meiofaunal taxa exhibited a vertical gradient possibly due to changes in the concentrations of oxygen and hydrogen sulphide, rather than food availability along this gradient. Nematodes are capable of distributing themselves throughout the whole sediment column due to their ability to tolerate reducing conditions; however depletion of communities along depth was evident. Their presence in deeper sediments (6 - 10 cm) suggests that certain species are adequately adapted to spend their entire life cycle in these harsh environments (where soluble tannins and decomposing organic matter predominate). Copepods showed a strong limitation to vertical distribution (concentrating in the top 2 cm), possibly in response to a sharp vertical decline in oxygenation within these organically enriched sediments. Rev. Biol. Trop. 56 (3): 1127-1134. Epub 2008 September 30.

Seasonal vertical distribution of fish larvae in the southern Gulf of Mexico

Espinosa-Fuentes,María de la Luz; Flores-Coto,César; Zavala-García,Faustino; Sanvicente-Añorve,Laura; Funes-Rodríguez,René
Fonte: UAM, Unidad Iztapalapa, Publicador: UAM, Unidad Iztapalapa,
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2013 EN
Relevância na Pesquisa
66.13%
Changes in the composition and abundance of fish larvae in the water column were analyzed throughout an annual cycle (1994-1995) in the southern Gulf of Mexico, in order to establish the difference between the habitat of the larvae and the effect of oceanographic events on larval vertical distribution. The study area comprised the continental shelf off Tabasco and Campeche in the southern Gulf of Mexico. Samples were collected at five water column levels: 0-6, 6-12, 12-18, 45-55 and 95-105 m. A total of 118 taxa were identified, 52 were dominant species, 33 were larvae of neritic parents and 19 were larvae of mesopelagic parents. The results indicate that the water column presented two layers above the 105 m depth: a surface layer (0-18 m) and a deep layer (45-105 m). The greatest density of larval species that inhabit neritic areas as adults was recorded in the surface layer (0-18 m), while larvae of which the parents inhabit mesopelagic areas were found in the deep layer (45-105 m). The mixing of the water column was the most important physical factor regarding the variation in the vertical distribution of the larvae of both groups, particularly in winter. However, the biology of each species and the habit to occupy a particular depth was the most important factor that determined their distribution in the water column.