The purpose of this study was to determine the distributions and abundances of microzooplankton across a front in the Irish Sea, and to test the hypothesis that the structure which develops within the microzooplankton community is the result of the interactions within the communities. Eight sites were sampled on May 1-2, 1989 along a transect from Liverpool Bay, England to Dundalk Bay, Ireland. The transect crossed both the Liverpool Bay and western Irish Sea fronts; sites were positioned with respect to water type (e.g., coastal, thermally mixed, thermally stratified) . Five sites were sampled by double Longhurst-Hardy Plankton Recorder (LHPR) to determine micro- and macrozooplankton distributions and to identify relationships between these distributions and hydrodynamic and biotic forcing. Microzooplankton samples were microscopically enumerated, and the abundance data processed by Correspondence Analysis to determine interrelationships among the taxa. Variability in depth-averaged microzooplankton distributions along the transect can be explained largely by the hydrodynamic processes associated with the thermal and density structure of the region. The microzooplankton in the coastal and central channel waters were distinct; the Liverpool Bay and western Irish Sea front apparently act as boundaries between microzooplankton assemblages. The vertical distributions of the microzooplankton at each site appear to be affected by biological interactions between taxa (e.g ., predation). Correspondence Analysis also identified a sub-surface microzooplankton assemblage off the north coast of Anglesey not associated with strong temperature or density gradients, but which was taxonomically distinct from microzooplankton assemblages at the other locations. A similarity between the microzooplankton assemblages in the surface stratified waters of the western Irish Sea front and the Irish coast (48 km west) was also detected. This suggests the possibility that microzooplankton along the Irish coast have been advected offshore in the coastal waters.

Submitted by Caroline Falcao (caroline.rfalcao@ufpe.br) on 2017-05-22T16:43:23Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Magalhães, G.M.O. Tese versão final.pdf: 1681761 bytes, checksum: 993b74d48394c8fed037a308d0cd9586 (MD5) / Made available in DSpace on 2017-05-22T16:43:23Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Magalhães, G.M.O. Tese versão final.pdf: 1681761 bytes, checksum: 993b74d48394c8fed037a308d0cd9586 (MD5) Previous issue date: 2014 / A presente tese teve como objetivo geral conhecer como a produtividade de Copepoda é afetada pelo grau de poluição em estuários. Para a estimativa da produtividade de Copepoda foram usadas regressões comprimento-peso para as principais espécies de Copepoda e foram utilizadas equações disponíveis na literatura para conversão de sua biomassa em produtividade secundária. Para acessar a massa d’água dominante foram obtidos dados de temperatura e salinidade e para obter informações sobre o grau de poluição foram medidos o oxigênio dissolvido e a clorofila-a. As amostras foram coletadas em uma estação fixa na Bacia do Pina, em marés de sizígia e quadratura com redes de plâncton com 64 e 200 μm de abertura de malha, através de arrastos horizontais superficiais. Foi também coletado sedimento para o cultivo em laboratório de cistos de resistência inseridos no mesmo, e importantes para uma possível recolonização de ambientes após períodos adversos, representando fonte potencial para o recrutamento de náuplios na coluna d’água. As maiores profundidades ocorreram durante as preamares de sizígia, com máximo de 2,50 m. A temperatura da água apresentou valores variando entre 26 e 31° C e a salinidade entre 26 e 37, evidenciando estuário variando de polihalino a euhalino. O oxigênio dissolvido indicou área poluída na baixa-mar com cerca de 40% de saturação, sendo esta poluição reduzida durante as preamares quando chega a mais de 100% de saturação. A clorofila-a apresentou altas concentrações com maiores valores médios na maré de quadratura (20 mL.L-1 ) em relação a sizígia (6 mL.L-1 ). O zooplâncton esteve representado por 44 taxa pertencentes aos clados Rotifera, Ciliophora, Foraminífera, Cnidaria, Mollusca, Bryozoa, Annelida, Arthropoda, Chaetognatha e Chordata. Copepoda destacou-se com 18 espécies, entre as quais foram frequentes e abundantes nas duas frações estudadas Oithona oswaldocruzi, O. hebes, Dioithona oculata, Parvocalanus crassirostris, Acartia lilljeborgi, Temora turbinata e Euterpina acutifrons. Este grupo caracteriza os estuários tropicais brasileiros. A densidade média mínima de Copepoda foi de 3420 ± 1906 ind.m-3 na maré de sizígia na fração do mesozooplâncton e o máximo foi de 80528 ± 51246 ind.m-3 na maré de quadratura na fração do microzooplâncton. Em termos gerais, a densidade de Copepoda na fração do microzooplâncton foi mais de 10 vezes a quantidade da fração do mesozooplâncton; na maré de quadratura, essa fração foi cerca de 3 vezes mais densa do que a encontrada na sizígia e cerca de 1,5 vezes mais que na fração do mesozooplâncton. Para as estimativas de produção foram consideradas: Oithona oswaldocruzi, O. hebes, D. oculata, Acartia lilljeborgi e Parvocalanus crassirostris, que juntas totalizaram mais de 60% de toda comunidade. Em termos de produção total, as taxas mais altas ocorreram durante a quadratura (10,07 mgC m -3 dia-1 , para a comunidade do microzooplâncton; e 6,1 mgC m -3 dia-1 , para o mesozooplâncton). Embora esse ecossistema estuarino apresente alto grau de poluição nas baixamares de quadratura, a mesma é amenizada pela grande penetração do fluxo marinho, apresentando o ambiente uma melhor qualidade nas preamares de sizígia. As taxas mais elevadas de produção no período de maior poluição mostram a grande resiliência das espécies estudadas de Copepoda aos impactos antropogênicos, contudo quando comparado a estuários similares observou-se, que a produção é reduzida pela forte poluição. / The present thesis aims to assess how the productivity of Copepods is affected by the degree of pollution in estuaries. For the estimation of productivity of Copepoda it was used length-weight regressions for the main species of Copepoda and equations available in the literature were used for conversion of biomass in secondary productivity. To access the dominant water mass it was measured temperature and salinity; and to access the pollution degree it was measured the dissolved oxygen and chlorophyll-a. The samples were collected in a fixed station in the Bacia do Pina in spring and neap tides using plankton nets with 64 and 200 μm mesh size, through horizontal surface hauls. It was also collected sediment for cultivation of resistance cysts in laboratory, important for testing a possible recolonization after adverse periods, representing the cysts potential source for the recruitment of nauplii in the water column. The greater depths occurred during spring high tides, with maximum of 2.50 m. The water temperature presented values varying between 26 and 31oC and salinity from 26 to 37, characterizing the estuary with a polihaline to euhaline regime. Dissolved oxygen indicated polluted area at low tide with about 40% of saturation, this pollution being reduced during the high tides when O2 attain more than 100% saturation. Chlorophyll-a presented high concentrations, with higher average values during neap tide (20 mL L-1 ) in relation to spring tide (6 mL L-1 ). The zooplankton was represented by 44 taxa belonging to clades Rotifera, Ciliophora, Foraminifera, Cnidaria, Mollusca, Bryozoa, Annelida, Arthropoda, Chaetognatha and Chordata. Copepoda outranked with 18 species, among them were frequent and abundant in the two net fractions studied Oithona oswaldocruzi, O. hebes, Dioithona oculata, Parvocalanus crassirostris, Acartia lilljeborgi, Temora turbinata and Euterpina acutifrons. This group characterizes the Brazilian tropical estuaries. The average minimum density of Copepods was 3420 ± 1906 ind.m-3 at spring tide in mesozooplankton fraction, and the maximum was 80528 ± 51246 ind.m-3 at neap tide in the microzooplankton net fraction. In general, the density of Copepoda in the fraction of microzooplankton was more than 10 times the amount of the fraction of the mesozooplankton; and neap tide was about 3 times more dense than spring tide for the fraction of the microzooplankton and about 1.5 times the amount of the fraction of the mesozooplankton. For production estimates were considered: Oithona oswaldocruzi, O. hebes, D. oculata, Acartia lilljeborgi and Parvocalanus crassirostris which together totaled more than 60% of the whole community. In terms of total production, the highest rates occurred during the neap tide (10.07 mgC m -3 dia-1 to the copepods in the microzooplankton, and 6.1 mgC m -3 dia-1 to the mesozooplankton fraction). Although this estuarine ecosystem present high degree of pollution during neap low tides, this pollution is ameliorated by the large penetration of the marine flow presented the environment a better quality during spring high tide. The higher production in the period of greatest pollution shows the great resilience of these Copepoda to anthropogenic impacts, however this production when compared to others similar estuaries has been reduced by pollution.

No description available.

A global increase in atmospheric CO2 and temperature is assumed to affect the marine ecosystems in numerous ways, e.g. by altering ocean circulation patterns and changing nutrient regimes. The changes are expected to impact heavily on both phytoplankton communities as well as the rest of the marine food-web. Based on previous experimental studies that have investigated the impacts of varied algae food-quality on zooplankton, this quantitative study hypothesizes that (i) the tested microzooplankton species Brachionus plicatilis (rotifer) and Euplotes sp. (ciliate) will show high population growth rates (g) when fed with Nannochloropsis sp. grown under nutrient replete conditions, (ii) that the species will show a population growth rate close to zero when fed with algae grown on phosphorous-deficient media and (iii) that microzooplankton will be negatively affected by the algae grown in nitrogen-deficient media. The study thus aims to investigate how changes in the balance of energy and several chemical elements in ecological interactions, ecological stoichiometry, affect the growth rates of algal grazers. The results show that food-independent factors had a large impact on growth rates and resulted in unexpected, deviating trends. However, as the growth rates for B. plicatilis fed with phosphorous-deficient algae were lower than those of B. plicatilis fed with nitrogen-deficient algae, there is some support for the / <p>The paper was written within the research-area of marine biology.</p>

A mesocosm experiment with four triplicated treatments (control, clear carbon, pigment and dissolved organic matter) was carried out to investigate the effects of light (by pigment addition) and carbon (C) on phytoplankton communities and on the grazing pressure of microzooplankton on phytoplankton in the Baltic Sea. Phytoplankton concentration and species composition were determined by using an inverted microscope following the Utermöhl method. In order to measure differences in phyto-zooplankton trophic interactions between treatments, a dilution experiment was performed at the end of the mesocosm experiment. Surprisingly, the results show that light attenuation was beneficial to phytoplankton production while carbon enrichment had negative effects on phytoplankton production, the highest phytoplankton production was in the low light treatment and lowest phytoplankton production was in the clear C treatment. Cyanobacteria were the most dominant group, representing over 95% of the phytoplankton community. Diatoms were the least dominant group, representing less than 5% of the phytoplankton community. Microzooplankton grazing pressure was affected by light attenuation and C enrichment. Grazing pressure was highest on cyanobacteria in the clear C treatment, but chrysophytes experienced low grazing pressure and had high growth rates in the Control treatment where microzooplankton fed selectively on chrysophytes. The least abundant group, diatoms, decreased although they experienced no grazing pressure in the Control and clear C treatments. This experiment resulted in two surprising findings. First, increased light intensity reduced phytoplankton biomass, especially in the clear C treatment, and second, cyanobacteria constituted an important food source for microzooplankton grazers. This study adds to the increasing evidence that light effects can be counterintuitive and that cyanobacteria are not necessarily grazing resistant and can meditate nutrient transport to higher trophic levels.

Zooplankton were sampled on a monthly basis at the Bermuda Atlantic Time-series Study (BATS) site from January 1995 to December 1999. Samples were collected using a 1-m², 200 µm mesh net. The net sampled the water column in an oblique manner from the surface to a mean depth of 200 m. One day and one night tow from each cruise was examined microscopically to determine the community structure of the non-calanoid copepods. In addition, a three year set of nighttime samples were examined taken by 0.5-m², 20 and 35 µm mesh nets (1995-1996 and 1997, respectively) towed obliquely to 150 m. The dominant orders in terms of overall abundance were the Cyclopoida and Poecilostomatoida. The cyclopoid genus, Oithona, was most abundant followed by the Poecilostomatoid family, Oncaeidae, and the genera Farranula and Corycaeus. Harpacticoids, although common, were about an order of magnitude less abundant and were dominated by Macrosetella gracilis. Representatives of the Mormonilloida and Siphonostomatoida also were frequently encountered, although in much lower numbers. Overall, pronounced seasonal signals were noted; highest abundances occurred during spring and lowest during winter. However, abundance of some groups peaked either in the fall or winter, with lowest abundance in spring or summer. Miraciid copepods are estimated to consume an overall average of 359 µg C m-2 d-1 and regenerate 55 µg N m-2 d-1 derived from Trichodesmium at BATS. Highest grazing and regeneration rates were found in late summer through fall and early winter and lowest in spring and early summer. The ecological consequences of miraciid copepod feeding on Trichodesmium are discussed. The 20-35 µm net samples revealed an astonishing abundance of non-copepod species, some totally missed and others woefully under-sampled by the 200 µm net. At least four species of oncaeid copepods and the harpacticoid copepod Microsetella norvegica were found in abundances that were more than an order of magnitude higher than the corresponding numbers of non-calanoid copepods sampled by the 200 µm net. The role of all non-calanoid copepods, from both net systems, in C and N dynamics at BATS is analyzed and discussed along with the sex-ratios of most identified species.

Foram estudadas a composição e a distribuição da abundância e da biomassa de grupos do microzooplâncton na plataforma e no talude da Bacia de Campos localizados na região sudeste da margem continental do Brasil, compreendida entre Vitória (20,5°S) e Cabo Frio (24°S). Foram coletadas amostras de microzooplâncton com rede Multinet de 64 ?m por meio de arrastos horizontais em cinco estratos de profundidade (do superficial ao batipelagial até 2300 m) e em dois períodos: período um (P1) março-abril/2009 e período dois (P2) agosto-setembro/2009. A abundância total variou de 1 a 56918 org./m³ no P1 e de 80 a 206732 org./m³ no P2, enquanto a biomassa total variou entre 2x10-5 e 2 mg/m³ no P1 e de 6x10-6 a 5 mg/m³ no P2. Os grupos taxonômicos mais frequentes (> 50% Frequência realtiva) no P1 foram Radiolaria, Tintinnina, Foraminifera, náuplios de Copepoda, Cyclopoida, Calanoida, Gastropoda, Pteropoda e Bivalvia. Já no P2 foram: Acantharia, Radiolaria, Tintinnina, Foraminifera, náuplios de Copepoda, Cyclopoida, Calanoida, Harpacticoida, Gastropoda, Bivalvia e Polychaeta. Os náuplios de Copepoda dominaram nasuperfície, com 65% de abundância relativa no P1 e P2, ao passo que organismos do protozooplâncton, como Radiolaria, Tintinnina e Foraminifera, foram os mais abundantes em águas profundas. Houve diferenças na abundância e na biomassa em resposta às variações ambientais, espaciais e sazonais na Água Tropical (AT-1 m) e Água Central do Atlântico Sul (ACAS-250 m). Estas variações podem estar relacionadas à ascenção de águas profundas ricas em nutrientes da ACAS até a zona eufótica, o que leva ao aumento de produtividade e ao aumento da produção primária em domínios neríticos da região, associado à frequente ocorrência de vórtices ciclônicos associados à Corrente do Brasil. Porém, nos estratos mais profundos (Água Intermediária Antártica (AIA-800 m), Água Circumpolar Superior (ACS-1200 m) e Água Profunda do Atlântico Norte (APAN-2300 m)), notou-se homogeneidade horizontal do microzooplâncton, associada à maior estabilidade termohalina. No entanto, vale ressaltar que os altos valores de Radiolaria nas águas profundas poderiam estar condicionados às características físicas e químicas da ACS. Neste trabalho foi possível concluir que a abundância e a biomassa do microzooplâncton foram maiores na camada superficial e na ACAS, devido as flutuações de temperatura e salinidade. Notou-se também uma variabilidade entre os períodos de coleta. A temperatura foi a variável que mais influenciou as concentrações de organismos, em contraste, a baixa flutuação da salinidade na Bacia de Campos não influenciou significativamente os grupos do microzooplâncton. Os dados da AIA, ACS e APAN obtidos neste trabalho são fundamentais para o conhecimento do ambiente meso e batipelagial ao longo do Brasil. Finalmente, a FlowCAM, utilizada para a análise semiautomática das amostras, foi uma ferramenta útil para a contagem e obtenção de informações morfométricas sobre o microzooplâncton. / The composition and the distribution of numerical abundance and biomass of microzooplankton groups were sutudied in the Campos Basin located southeastern Brazil, between Victoria (20.5°S) and Frio Cape (24°S). Microzooplankton samples were collected with horizontal hauls using a Multinet (64 ?m) in five depth layers (surface up to 2300m bathypelagial zone) and in two seasonal periods: Period one (P1) May, April - 2009 and Period two (P2) August, September - 2009 (HABITATS CENPES / PETROBRAS). The total abundance ranged from 1 to 57 Org/m³ during the P1 and from 80 to 207 Org/m³ during the P2. Total biomass ranged from 2x10-5 to 2 mg/m³ during the P1, and from 6x10-6 to 5 mg/m³ during the P2. Most frequent taxonomic groups (> 50% relative frequency) in P1 were Radiolaria, Tintinnina, Foraminifera, Copepod nauplii, Cyclopoida, Calanoida, Gastropoda, Pteropoda, and Bivalvia. In P2, the most frequent taxonomic groups were Acantharia, Radiolaria, Tintinnina, Foraminifera, Copepod nauplii, Cyclopoida, Calanoida, Harpacticoida, Gastropoda, Bivalvia, and Polychaeta. Copepod nauplii dominated the surface samples, with 65% of relative abundance during both periods; Radiolaria, Tintinnina and Foraminifera dominated the deep water samples. There were differences in the abundance and biomass in response to environmental, spatial and seasonal variationsn the Tropical Water (TW-1 m) and in the South Central Atlantic Water (SCAW-250 m), These variations may related tothe rise of nutrient-rich deep waters of the SCAW to the euphotic zone, which leads to the increase of the productivity and the increase of the primary production in neritic areas, linking it to the frequent occurrence of cyclonic vortices associated with Brazil Current. In the deepest layers Antarctic Intermediate Water (AAIW-800 m), Upper Circumpolar Water (UCW-1200 m) and North Atlantic Deep Water (NADW-2300 m) it was noted a horizontal homogeneity of the microzooplankton associated with thermohaline stability. However, it is noteworthy that the high values of Radiolaria in deep water could be conditioned by the physical and chemical characteristics of the UCW. It was possible to conclude thatthe abundance and biomass of microzooplankton were higher in the surface layer and SCAW, f due to climatic fluctuations of temperature and salinity.. The temperature was the variable that most influenced the concentrations of organisms; in contrast, the low salinity fluctuations in the Campos Basin had no significant influence on the groups of microzooplankton. The data from AAIW, UCW, and NADW obtained in this work are fundamental for the understanding of the mesopelagical and bathypelagical zones in the Brazilian oceanic waters. Finally the FlowCAM used for semi-automatic analysis of samples was a useful tool for counting and obtaining information about the morphometric microzooplankton.

Foram estudadas a composição e a distribuição da abundância e da biomassa de grupos do microzooplâncton na plataforma e no talude da Bacia de Campos localizados na região sudeste da margem continental do Brasil, compreendida entre Vitória (20,5°S) e Cabo Frio (24°S). Foram coletadas amostras de microzooplâncton com rede Multinet de 64 ?m por meio de arrastos horizontais em cinco estratos de profundidade (do superficial ao batipelagial até 2300 m) e em dois períodos: período um (P1) março-abril/2009 e período dois (P2) agosto-setembro/2009. A abundância total variou de 1 a 56918 org./m³ no P1 e de 80 a 206732 org./m³ no P2, enquanto a biomassa total variou entre 2x10-5 e 2 mg/m³ no P1 e de 6x10-6 a 5 mg/m³ no P2. Os grupos taxonômicos mais frequentes (> 50% Frequência realtiva) no P1 foram Radiolaria, Tintinnina, Foraminifera, náuplios de Copepoda, Cyclopoida, Calanoida, Gastropoda, Pteropoda e Bivalvia. Já no P2 foram: Acantharia, Radiolaria, Tintinnina, Foraminifera, náuplios de Copepoda, Cyclopoida, Calanoida, Harpacticoida, Gastropoda, Bivalvia e Polychaeta. Os náuplios de Copepoda dominaram nasuperfície, com 65% de abundância relativa no P1 e P2, ao passo que organismos do protozooplâncton, como Radiolaria, Tintinnina e Foraminifera, foram os mais abundantes em águas profundas. Houve diferenças na abundância e na biomassa em resposta às variações ambientais, espaciais e sazonais na Água Tropical (AT-1 m) e Água Central do Atlântico Sul (ACAS-250 m). Estas variações podem estar relacionadas à ascenção de águas profundas ricas em nutrientes da ACAS até a zona eufótica, o que leva ao aumento de produtividade e ao aumento da produção primária em domínios neríticos da região, associado à frequente ocorrência de vórtices ciclônicos associados à Corrente do Brasil. Porém, nos estratos mais profundos (Água Intermediária Antártica (AIA-800 m), Água Circumpolar Superior (ACS-1200 m) e Água Profunda do Atlântico Norte (APAN-2300 m)), notou-se homogeneidade horizontal do microzooplâncton, associada à maior estabilidade termohalina. No entanto, vale ressaltar que os altos valores de Radiolaria nas águas profundas poderiam estar condicionados às características físicas e químicas da ACS. Neste trabalho foi possível concluir que a abundância e a biomassa do microzooplâncton foram maiores na camada superficial e na ACAS, devido as flutuações de temperatura e salinidade. Notou-se também uma variabilidade entre os períodos de coleta. A temperatura foi a variável que mais influenciou as concentrações de organismos, em contraste, a baixa flutuação da salinidade na Bacia de Campos não influenciou significativamente os grupos do microzooplâncton. Os dados da AIA, ACS e APAN obtidos neste trabalho são fundamentais para o conhecimento do ambiente meso e batipelagial ao longo do Brasil. Finalmente, a FlowCAM, utilizada para a análise semiautomática das amostras, foi uma ferramenta útil para a contagem e obtenção de informações morfométricas sobre o microzooplâncton. / The composition and the distribution of numerical abundance and biomass of microzooplankton groups were sutudied in the Campos Basin located southeastern Brazil, between Victoria (20.5°S) and Frio Cape (24°S). Microzooplankton samples were collected with horizontal hauls using a Multinet (64 ?m) in five depth layers (surface up to 2300m bathypelagial zone) and in two seasonal periods: Period one (P1) May, April - 2009 and Period two (P2) August, September - 2009 (HABITATS CENPES / PETROBRAS). The total abundance ranged from 1 to 57 Org/m³ during the P1 and from 80 to 207 Org/m³ during the P2. Total biomass ranged from 2x10-5 to 2 mg/m³ during the P1, and from 6x10-6 to 5 mg/m³ during the P2. Most frequent taxonomic groups (> 50% relative frequency) in P1 were Radiolaria, Tintinnina, Foraminifera, Copepod nauplii, Cyclopoida, Calanoida, Gastropoda, Pteropoda, and Bivalvia. In P2, the most frequent taxonomic groups were Acantharia, Radiolaria, Tintinnina, Foraminifera, Copepod nauplii, Cyclopoida, Calanoida, Harpacticoida, Gastropoda, Bivalvia, and Polychaeta. Copepod nauplii dominated the surface samples, with 65% of relative abundance during both periods; Radiolaria, Tintinnina and Foraminifera dominated the deep water samples. There were differences in the abundance and biomass in response to environmental, spatial and seasonal variationsn the Tropical Water (TW-1 m) and in the South Central Atlantic Water (SCAW-250 m), These variations may related tothe rise of nutrient-rich deep waters of the SCAW to the euphotic zone, which leads to the increase of the productivity and the increase of the primary production in neritic areas, linking it to the frequent occurrence of cyclonic vortices associated with Brazil Current. In the deepest layers Antarctic Intermediate Water (AAIW-800 m), Upper Circumpolar Water (UCW-1200 m) and North Atlantic Deep Water (NADW-2300 m) it was noted a horizontal homogeneity of the microzooplankton associated with thermohaline stability. However, it is noteworthy that the high values of Radiolaria in deep water could be conditioned by the physical and chemical characteristics of the UCW. It was possible to conclude thatthe abundance and biomass of microzooplankton were higher in the surface layer and SCAW, f due to climatic fluctuations of temperature and salinity.. The temperature was the variable that most influenced the concentrations of organisms; in contrast, the low salinity fluctuations in the Campos Basin had no significant influence on the groups of microzooplankton. The data from AAIW, UCW, and NADW obtained in this work are fundamental for the understanding of the mesopelagical and bathypelagical zones in the Brazilian oceanic waters. Finally the FlowCAM used for semi-automatic analysis of samples was a useful tool for counting and obtaining information about the morphometric microzooplankton.

Submitted by Caroline Falcao (caroline.rfalcao@ufpe.br) on 2017-05-25T17:38:36Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Figueiredo, L. Dissertação.pdf: 2326085 bytes, checksum: f701ac448a676622b5e8d0f8bd978613 (MD5) / Made available in DSpace on 2017-05-25T17:38:36Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Figueiredo, L. Dissertação.pdf: 2326085 bytes, checksum: f701ac448a676622b5e8d0f8bd978613 (MD5) Previous issue date: 2014-02-07 / Este estudo teve como objetivo analisar a dinâmica da comunidade e da produção secundária dos Copepoda do microzooplâncton dos recifes costeiros de Tamandaré, PE, para entender as variações sazonais e nictemerais, e relativas as fases lunares e os principais processos que influenciam essa comunidade. Amostras foram coletadas através de arrastos horizontais com rede de plâncton (65μm de abertura de malha) durante o período chuvoso (Julho-Agosto 2010) e seco (Novembro-Dezembro 2010), nos horários diurno e noturno e durante cada fase lunar. Cinqüenta e oito taxa foram identificados. Copepoda com 23 espécies dominou e compôs aproximadamente 50% da comunidade durante o período seco. As espécies mais abundantes foram Euterpina acutifrons, Parvocalanus crassirostris e Oithona hebes. Os maiores valores de densidade foram registrados durante o período seco (10711.19 ± 7131.47 ind.*m-3 ). Embora que foram observadas maiores diferenças quantitativas entre os horários de coleta e as fases lunares, diferenças qualitativas foram observadas. A produção foi considerada baixa e refletiu os padrões da densidade, estando mais elevada no período seco (P. crassirostris 101,62 ± 159,03 μg C m-3 dia-1 ; E. acutifrons 75,75 ± 82,77 μg C m-3 dia-1 ; Oithona hebes 24,77 ± 19,43 μg C m-3 dia-1 ). Não foi observada diferença nos valores de produção entre as fases lunares. Entre os horários, as diferenças estiveram restritas apenas a E. acutifrons. De forma geral pôde-se observar a forte influência sazonal sobre a composição da comunidade do microzooplâncton e produção dos Copepoda do sistema recifal de Tamandaré, no qual a grande ocorrência de espécies estuarinas e costeiras ressalta a interação entre o sistema recifal e os estuários próximos. / This study aimed to analyze the dynamics of the microzooplankton community of the coastal reefs of Tamandaré, PE, to understand the seasonal and diel variations in relation to lunar phases and the main processes influencing the community. Samples were collected by horizontal hauls with a plankton net (65μm mesh size) in the rainy (July-August 2010) and dry (November-December 2010) seasons, during daytime and at night, and during every lunar phase. Fifty-eight taxa were identified. Copepoda, with 23 species, dominated and comprised nearly 50% of the community during the dry season. The most abundant species were Euterpina acutifrons and Parvocalanus crassirostris. Higher densities were registered during the dry season (10711.19 ± 7131.47 ind.*m-3 ). Although major quantitative differences were not observed between collection times and lunar phases, qualitative differences were observed. The secondary production was considered low, and followed the density pattern, being higher during the dry season (P. crassirostris 101,62 ± 159,03 μg C m-3 dia-1 ; E. acutifrons 75,75 ± 82,77 μg C m-3 dia-1 ; Oithona hebes 24,77 ± 19,43 μg C m-3 dia-1 ). Differences between the lunar phases were absent, and differences between the daytime and nighttime were restricted to E. acutifrons. The overall results showed the strong seasonality influence over the copepods community, both in terms of composition and production. The dominance of estuarine and coastal species indicates the connection between the reef system and adjacent estuaries.

O objetivo desta tese foi o estudo da variabilidade temporal, crescimento e produção do zooplâncton metazoário, com ênfase sobre estágios imaturos de copépodes, na região costeira de Ubatuba (SP, Brasil). Para tal, a comunidade zooplanctônica foi estudada durante as estações de verão e inverno em regime de dias alternados, para os anos de 2009 a 2011, através de coletas realizadas com redes de malha de 20 e 100 m. Índices ecológicos como densidade, diversidade e equitabilidade foram calculados. Os estágios imaturos de copépodes foram submetidos a experimentos de coortes artificiais em quatro classes de tamanho (50-80, 80-100, 100-150 e 150-200 m) para a determinação das taxas de crescimento de 14 táxons em diferentes estágios de desenvolvimento. A biomassa foi estimada através de equações de regressão comprimento-peso para o posterior cálculo da produção secundária. A incidência e possíveis efeitos de um protista alveolado parasita (Ellobiopsis sp.) sobre o crescimento de copépodes hospedeiros, com ênfase sobre a família Paracalanidae, também foi avaliada. A comunidade de copépodes esteve representada por 66 espécies e caracterizada por valores relativamente altos de diversidade e equitabilidade em relação aos demais trabalhos na plataforma interna da região sudeste do país. Os copépodes foram o grupo dominante, sendo que estágios naupliares foram os mais comuns para a rede de 20 m, enquanto que copepoditos juvenis dominaram para a rede de 100 m. A densidade do zooplâncton foi altamente variável, sendo os maiores valores registrados para o inverno de 2011 para a malha de 20 m (33.160 ± 23.136 org. m-3) e os menores para o inverno de 2009 para a malha de 100 m (5.393 ± 2.264 org. m-3). As famílias dominantes de copépodes foram Oithonidae, Oncaeidae, Paracalanidae e Acartiidae, sendo a primeira dominante também em termos de biomassa. Os estágios juvenis dos copépodes representaram uma biomassa entre 1,06 a 3,47 mg C m-3 para o inverno de 2010 e verão de 2009 respectivamente. Taxas de crescimento foram obtidas para sete táxons de Calanoida (0,41 ± 0,21 d-1), cinco de Cyclopoida (0,27 ± 0,17 d-1) e dois de Harpacticoida (0,31 ± 0,16 d-1). Os valores de crescimento foram semelhantes entre as diferentes classes de tamanho e as estações do ano, mas foram substancialmente diferentes entre as ordens, sendo geralmente maiores para os Calanoida. A produção média estimada para os estágios imaturos dos táxons dominantes de copépodes foi igual a 0,45 mg C m-3, valor conservativo por não contemplar as espécies de menor densidade e frequência. O crescimento de copépodes da família Paracalanidae, principalmente Parvocalanus crassirostris, foi afetado pelo protista parasita Ellobiopsis sp., uma vez que as fêmeas adultas infectadas foram significativamente menores do que as normais. Cerca de 5% das fêmeas da espécie estiveram infectadas pelo parasita, que provavelmente afeta o crescimento somático e reprodutivo de P. crassirostris, com efeitos ainda desconhecidos em termos de biomassa e produção. As taxas calculadas de crescimento e a produção são semelhantes às de outros trabalhos em regiões tropicais. A abordagem experimental através de coortes artificiais forneceu os primeiros resultados sobre o crescimento de estágios juvenis de copépodes para uma região subtropical do Atlântico Sul Ocidental e demonstrou que a concentração da clorofila-a não foi um fator limitante. Este é um dos poucos trabalhos a disponibilizar dados de crescimento, biomassa e produção de tais estágios em ecossistemas marinhos tropicais e que padroniza o método de coortes artificiais para obtenção do crescimento / This thesis aimed to evaluate the temporal variability of the metazoan zooplankton density, growth, and production, with emphasis on copepod immature stages in the coastal area of Ubatuba (São Paulo, Brazil). The zooplankton community was studied during summer and winter from 2009 to 2011, by means of sampling with 20 and 100 m mesh-sized nets. Ecological indexes such as density, diversity and evenness were calculated. Growth rates for 14 taxa of copepod juvenile stages were determined by the artificial cohort method, in four size classes and different developmental stages (50-80, 80-100, 100-150 and 150-200 m). Biomass was estimated by the use of length-weight regressions followed by secondary production estimates. The incidence and possible effects of the alveolate parasite Ellobiopsis sp. on the growth of the copepod hosts was also investigated, with emphasis on the Paracalanidae family. The copepod assemblage was represented by 66 species and displayed relatively high diversity and evenness, in comparison to other studies in the inner shelf of the Brazilian southeastern coast. Copepod was the dominant group; nauplii in the 20 m net, and juvenile copepodids in the 100 m net. The zooplankton density was highly variable: the highest densities occurred during winter 2011 in the 20 m samples (33,160 ± 23,136 org. m-3) and the lowest for the winter 2009 in the 100 m samples (5,393 ± 2,264 org. m-3). The dominant copepod families were Oithonidae, Oncaeidae, Paracalanidae and Acartiidae, the former being the main taxa in terms of biomass as well. Juvenile copepod biomass varied between 1.06 and 3.47 mg C m-3 in the winter 2010 and summer 2009, respectively. Growth rates were recorded for seven Calanoida (0.41 ± 0.21 d-1), five Cyclopoida (0.27 ± 0.17 d-1) and two Harpacticoida (0.31 ± 0.16 d-1) taxa. Growth values were similar between the different size classes, seasons and years, but were substantially different between copepod orders (higher rates for the Calanoida). The mean production for all immature copepod stages was 0.45 mg C m-3, a conservative value, since rare species were not accounted for. The growth of the Paracalanidae copepod Parvocalanus crassirostris, was affected by the parasite protist Ellobiopsis sp., since infected adult females were significantly smaller than normal individuals. About 5% of adult females were infected by the parasite, which probably reduced somatic and reproductive growth of P. crassirostris, with potential consequences for biomass accumulation and, consequently, production. Growth and production rates were similar to those found in other studies carried out in tropical regions. The artificial cohort method has been applied here for the first time on the tropical and subtropical Southwest Atlantic, where clorophyl-a concentration was not considered a limiting factor for growth rates. This is one of the few studies providing data on growth, biomass and production for copepod juvenile stages in tropical marine ecosystems and standardizing the artificial cohort method to measure the growth rates