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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Variação temporal da comunidade de Copepoda Harpacticoida de fital num cenário de mudanças climáticas

NASCIMENTO, Rodolfo Ferreira Martins do 27 October 2015 (has links)
Submitted by Fernanda Rodrigues de Lima (fernanda.rlima@ufpe.br) on 2018-10-09T19:28:56Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Rodolfo Ferreira Martins do Nascimento.pdf: 1424442 bytes, checksum: b547042e60ca0f385c851cd73be379b8 (MD5) / Approved for entry into archive by Alice Araujo (alice.caraujo@ufpe.br) on 2018-11-21T18:46:28Z (GMT) No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Rodolfo Ferreira Martins do Nascimento.pdf: 1424442 bytes, checksum: b547042e60ca0f385c851cd73be379b8 (MD5) / Made available in DSpace on 2018-11-21T18:46:28Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Rodolfo Ferreira Martins do Nascimento.pdf: 1424442 bytes, checksum: b547042e60ca0f385c851cd73be379b8 (MD5) Previous issue date: 2015-10-27 / FACEPE / A partir do século XVIII, atividades humanas tais como as emissões de gases de efeito estufa têm se tornado um componente adicional que afeta o sistema climático. De acordo com o IPCC (Painel Intergovernamental de Mudanças Climáticas), a concentração atmosférica desses gases vai continuar a subir. Assim, é esperado um aumento da temperatura média entre 1,4 a 5,8°C até ao final do século 21. O aumento das concentrações de gases de efeito estufa, também podem causar um decréscimo no pH das águas da superfície oceânica de até 0,4 unidades em 2100. Essa alteração de pH, influencia na formação de recifes de corais, animais e algas calcificantes. O objetivo deste trabalho foi avaliar a variação temporal na composição e abundância das famílias de Copepoda Harpacticoida em ambiente natural e em condição experimental de diminuição de pH e aumento de temperatura da água do mar, com as hipóteses de que o aumento da acidez e temperatura da água do mar modifica a estrutura da associação e reduz significativamente a riqueza e equitabilidade de Harpacticoida. Trinta e duas algas (Halimeda sp.) coletadas na Praia de Serrambi – PE foram mantidas em condições laboratoriais de controle e de Cenário de mudança climática, no último sendo alterados o pH e temperatura da água de acordo com previsões para 2100, utilizando aquários preparados para injeção de CO₂ e controle de temperatura. O experimento de laboratório teve duração de 30 dias, sendo realizadas coletas de algas na mesma praia ao início de final do experimento. As algas foram processadas para retirada e identificação dos Copepoda Harpacticoida assim como para análises de clorofila. Foram registradas 17 famílias de Copepoda Harpacticoida. A família Ameiridae foi identificada ao nível específico, sendo encontradas 18 espécies. Os resultados das análises das algas indicaram um efeito significativo do cenário de mudança climática sobre a proporção de clorofilas e aumento da calcificação de Halimeda sp.. Resultados estatísticos mostraram diferenças significativas na estrutura da comunidade de Copepoda Harpacticoida entre a situação controle e o cenário previsto para 2100. A associação de espécies de Ameiridae não apresentou alteração sob condições de mudança climática, um maior tempo de exposição dos animais a condições de acidificação, poderia mostrar resultado significativo para as espécies estudadas, aproximando a família Ameiridae ao resultado obtido para os Harpacticoida. / From the eighteenth century, human activities such as emissions of greenhouse gases have become an additional component that affects the climate system. According to the IPCC (Intergovernmental Panel on Climate Change), the atmospheric concentration of these gases will continue to rise. Thus, it is expected to increase the average temperature of 1.4 to 5.8 ° C by the end of the 21st century. The increase in greenhouse gas concentrations, can also cause a decrease in the pH of ocean surface waters of up to 0.4 units in 2100. This change of pH, influence the formation of coral reefs, animals and calcifying algae. The objective of this study was to evaluate the temporal variation in the composition and abundance of the families of Copepoda Harpacticoida natural environment and experimental condition of decreased pH and increased temperature of sea water, with the hypothesis that the increase in acidity and temperature seawater modifies the structure of the pool and significantly reduces the richness and evenness of Harpacticoida. Thirty-two algae (Halimeda sp.) Collected in Serrambi Beach - PE were kept in laboratory conditions control and climate change scenario, the latter being altered pH and temperature according to forecasts water to 2100, using prepared aquariums for injection of CO2 and temperature control. The laboratory experiment lasted 30 days, algae collections being held on the same beach at the beginning of the end of the experiment. The algae were removed and processed for identification of Copepoda Harpacticoida as well as of chlorophyll analysis. 17 families of Copepoda Harpacticoida were recorded. The Ameiridae family was identified to species level, and found 18 species. The results of the analysis of algae showed a significant effect of climate change scenario on the proportion of chlorophylls and increased calcification of Halimeda sp .. Statistical results showed significant differences in Copepoda Harpacticoida community structure between the control situation and the scenario for 2100. the combination of species Ameiridae showed no change under conditions of climate change, a longer exposure of animals acidification conditions, could show significant results for the species studied, approaching Ameiridae family to the result for Harpacticoida.
62

Some aspects of the biology and distribution of the planktonic copepods of the Canadian Basin in the Arctic Ocean

Bulleid, Elizabeth, 1947- January 1972 (has links)
No description available.
63

Seasonal cycles, population dynamics, and production of copepods in the Arctic.

Cairns, Alan Andrew January 1969 (has links)
No description available.
64

Distribuição espacial e estrutura da comunidade de crustáceos de águas intersticiais de um igarapé amazônico e um riacho da mata atlântica / Spatial distribution and structure of interstitial water crustacean assemblages in an Amazonian stream and an Atlantic forest stream

Andrade, Luciana Paes de 03 May 2007 (has links)
As comunidades da fauna de copépodes de águas intersticiais da zona hiporrêica de um igarapé da Amazônia Central e de um rio da mata atlântica da região Sudeste do Brasil são comparadas quanto à composição, diversidade, e distribuição dos organismos. A relação das espécies identificadas com os fatores abióticos é analisada, com o objetivo de se estabelecer quais são os fatores determinantes para a distribuição das mesmas. Os fatores abióticos mensurados são: temperatura, pH, oxigênio dissolvido e granulometria do sedimento. Na areia grossa, há dominância de copepoditos e do gênero Forficatocaris (uma espécie para a mata atlântica e duas novas para a Amazônia). Essas três espécies e os copepoditos exploram o mesmo tipo de micro-hábitat no substrato. Quando a areia média é o substrato predominante, há o aumento na presença dos outros gêneros, como Potamocaris (uma espécie para a mata atlântica e uma nova espécie para a Amazônia) e Parastenocaris (mata atlântica), além do declínio no número de copepoditos. Há uma relação direta entre a temperatura e a distribuição dos microcrustáceos, ocorrendo o predomínio destes animais em temperaturas mais baixas. Há diferenças significativas dos valores de pH quando comparadas localidades distintas (Amazônia e mata atlântica); no entanto, quando comparadas as estações seca e chuvosa de um mesmo local, essa diferença não aparece. Sugere-se que o pH influencie na composição das espécies, e não em sua distribuição. Há um número similar de espécies ocupando os dois ambientes e um padrão de distribuição da fauna hiporrêica. Estas semelhanças apontam para a existência de padrões na estrutura e funcionamento destas comunidades naturais de microcrustáceos intersticiais, moldadas por pressões seletivas parecidas. / The assemblages of the copepod fauna from interstitial waters in the hyporheic zones from a stream in Central Amazon and a stream in the Atlantic rainforest of southeastern Brazil were compared in terms of composition, diversity and organism distribution. The relation of the identified species with abiotic factors was analyzed, aiming at establishing which factors were determinant for their distribution. The abiotic factors analyzed were: temperature, pH, dissolved oxygen, and sediment granulometry. In thick sand, there is predominance of copepodites and of the genus Forficatocaris (one species found in the Atlantic rainforest and two new species in the Amazon). These three species of Forficatocaris and the copepodites explore the same kind of microhabitat in the sediment. When medium size of sand grains prevail, there is an increase in the presence of other genera, such as Potamocaris (one species for the Atlantic rainforest and one new species for the Amazon) and Parastenocaris (Atlantic rainforest), besides a decline in number of copepodites. There is a direct ratio between the temperature and the distribution of microcrustaceans, with a predominance of these invertebrates in lower temperatures. There are significant differences in pH values when both localities (Amazon and Atlantic rainforest) are compared; however, comparisons between seasons (lower rainfall versus rainy periods) in a same location did not yield differences. It is suggested that the pH influences species composition, but not species distribution. There is a similar number of species inhabiting both environments and a distribution pattern for the hyporheic fauna. These similarities point at the existence of patterns in the structure and behavior in these natural communities of interstitial microcrustaceans, molded by similar selective pressures.
65

Ecology of Calanus sinicus (copepoda, calanoida) in oceans of Southern China.

January 2003 (has links)
by Lee Ka Lun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 153-167). / Abstracts in English and Chinese. / Abstract (in English) --- p.i / Abstract (in Chinese) --- p.iv / Acknowledgements --- p.vi / List of Figures --- p.vii / List of Tables --- p.xv / Chapter Chapter 1 --- General Introduction --- p.1 / Chapter Chapter 2 --- "Seasonal population structure, life cycle and body allometry of the planktonic copepod Calanus sinicus" / Chapter 2.1 --- Literature Review / Chapter 2.1.1 --- Taxonomy of Calanidae --- p.6 / Chapter 2.1.2 --- Geographical and seasonal distribution of Calanus sinicus --- p.7 / Chapter 2.1.3 --- Body length and body weight of Calanus sinicus --- p.11 / Chapter 2.2 --- Introduction --- p.14 / Chapter 2.3 --- Materials and Methods --- p.17 / Chapter 2.3.1 --- Field sampling --- p.17 / Chapter 2 3.2 --- Identification and enumeration of zooplankton --- p.19 / Chapter 3 3.2 --- Body length and weight of Calanus sinicus --- p.19 / Chapter 2.4 --- Results --- p.20 / Chapter 2.4.1 --- Temperature --- p.20 / Chapter 2.4.2 --- Salinity --- p.21 / Chapter 2.4.3 --- Ambient Chlorophyll a concentration --- p.22 / Chapter 2.4.4 --- Seasonal occurrence and distribution of Calanus sinicus in northern Taiwan --- p.23 / Chapter 2.4.5 --- Seasonal occurrence and distribution of Calanus sinicus in Hong Kong --- p.26 / Chapter 2.4.6 --- Life cycle of Calanus sinicus in northern Taiwan --- p.27 / Chapter 2.4.7 --- Life cycle of Calanus sinicus in Hong Kong --- p.28 / Chapter 2.4.8 --- Stage ratio index --- p.28 / Chapter 2.4.9 --- Seasonal changes in biomass of Calanus sinicus --- p.29 / Chapter 2.4.10 --- Seasonal changes in the abundances of other copepods in northern Taiwan --- p.29 / Chapter 2.4.11 --- Seasonal changes in the abundances of other copepods in Hong Kong --- p.30 / Chapter 2.4.12 --- Seasonal changes in biomass of other copepods --- p.31 / Chapter 2.4.13 --- Seasonal variations in body size --- p.31 / Chapter 2.4.14 --- Seasonal changes in sex composition in adults --- p.32 / Chapter 2.5 --- Discussions --- p.32 / Chapter Chapter 3 --- Diel vertical migration and gut pigment rhythm of the planktonic copepod Calanus sinicus / Chapter 3.1 --- Literature review --- p.87 / Chapter 3.1.1 --- Diel vertical migration of Calanus sinicus --- p.87 / Chapter 3.1.2 --- Diel feeding rhythm of Calanus sinicus --- p.91 / Chapter 3.1.3 --- Measurement of grazing rate --- p.93 / Chapter 3.2 --- Introduction --- p.96 / Chapter 3.3 --- Materials and Methods --- p.98 / Chapter 3.3.1 --- Zooplankton sampling and physical parameters --- p.98 / Chapter 3.3.2 --- Identification and enumeration --- p.100 / Chapter 3.3.3 --- Gut pigment fluorescence --- p.100 / Chapter 3.4 --- Results --- p.101 / Chapter 3.4.1 --- Temperature and salinity --- p.101 / Chapter 3.4.2 --- Ambient chlorophyll a concentration --- p.102 / Chapter 3.4.3 --- Diel vertical migration --- p.103 / Chapter 3.4.4 --- Gut pigment content --- p.106 / Chapter 3.5 --- Discussion --- p.107 / Chapter Chapter 4 --- Use of molecular markers in population analysis of Calanus sinicus / Chapter 4.1 --- Literature Review --- p.134 / Chapter 4.2 --- Introduction --- p.138 / Chapter 4.3 --- Materials and Methods --- p.142 / Chapter 4.3.1 --- "Collection, preservation, and identification of Calansn sinicus samples" --- p.142 / Chapter 4.3.2 --- DNA sequence determination for Calanus sinicus --- p.143 / Chapter 4.4 --- Results --- p.144 / Chapter 4.5 --- Discussion --- p.145 / Chapter Chapter 5 --- Conclusion --- p.150
66

On the population ecology of the toxigenic marine diatom genus, Pseudo-nitzschia : perspectives from the growth and mortality environments /

Olson, M. Brady January 2006 (has links)
Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 145-160).
67

Distribuição espacial e estrutura da comunidade de crustáceos de águas intersticiais de um igarapé amazônico e um riacho da mata atlântica / Spatial distribution and structure of interstitial water crustacean assemblages in an Amazonian stream and an Atlantic forest stream

Luciana Paes de Andrade 03 May 2007 (has links)
As comunidades da fauna de copépodes de águas intersticiais da zona hiporrêica de um igarapé da Amazônia Central e de um rio da mata atlântica da região Sudeste do Brasil são comparadas quanto à composição, diversidade, e distribuição dos organismos. A relação das espécies identificadas com os fatores abióticos é analisada, com o objetivo de se estabelecer quais são os fatores determinantes para a distribuição das mesmas. Os fatores abióticos mensurados são: temperatura, pH, oxigênio dissolvido e granulometria do sedimento. Na areia grossa, há dominância de copepoditos e do gênero Forficatocaris (uma espécie para a mata atlântica e duas novas para a Amazônia). Essas três espécies e os copepoditos exploram o mesmo tipo de micro-hábitat no substrato. Quando a areia média é o substrato predominante, há o aumento na presença dos outros gêneros, como Potamocaris (uma espécie para a mata atlântica e uma nova espécie para a Amazônia) e Parastenocaris (mata atlântica), além do declínio no número de copepoditos. Há uma relação direta entre a temperatura e a distribuição dos microcrustáceos, ocorrendo o predomínio destes animais em temperaturas mais baixas. Há diferenças significativas dos valores de pH quando comparadas localidades distintas (Amazônia e mata atlântica); no entanto, quando comparadas as estações seca e chuvosa de um mesmo local, essa diferença não aparece. Sugere-se que o pH influencie na composição das espécies, e não em sua distribuição. Há um número similar de espécies ocupando os dois ambientes e um padrão de distribuição da fauna hiporrêica. Estas semelhanças apontam para a existência de padrões na estrutura e funcionamento destas comunidades naturais de microcrustáceos intersticiais, moldadas por pressões seletivas parecidas. / The assemblages of the copepod fauna from interstitial waters in the hyporheic zones from a stream in Central Amazon and a stream in the Atlantic rainforest of southeastern Brazil were compared in terms of composition, diversity and organism distribution. The relation of the identified species with abiotic factors was analyzed, aiming at establishing which factors were determinant for their distribution. The abiotic factors analyzed were: temperature, pH, dissolved oxygen, and sediment granulometry. In thick sand, there is predominance of copepodites and of the genus Forficatocaris (one species found in the Atlantic rainforest and two new species in the Amazon). These three species of Forficatocaris and the copepodites explore the same kind of microhabitat in the sediment. When medium size of sand grains prevail, there is an increase in the presence of other genera, such as Potamocaris (one species for the Atlantic rainforest and one new species for the Amazon) and Parastenocaris (Atlantic rainforest), besides a decline in number of copepodites. There is a direct ratio between the temperature and the distribution of microcrustaceans, with a predominance of these invertebrates in lower temperatures. There are significant differences in pH values when both localities (Amazon and Atlantic rainforest) are compared; however, comparisons between seasons (lower rainfall versus rainy periods) in a same location did not yield differences. It is suggested that the pH influences species composition, but not species distribution. There is a similar number of species inhabiting both environments and a distribution pattern for the hyporheic fauna. These similarities point at the existence of patterns in the structure and behavior in these natural communities of interstitial microcrustaceans, molded by similar selective pressures.
68

Ocean acidification : impacts on copepod growth and reproduction

Cripps, Gemma Louise January 2014 (has links)
No description available.
69

The life history and annual cycle of some bottom living copepods (calanoids) from western Norway

Matthews, J. B. L. January 1962 (has links)
No description available.
70

Egg production of Calanus pacificus Brodsky and its relationship to seasonal changes in phytoplankton availability /

Runge, Jeffrey Albert. January 1981 (has links)
Thesis (Ph. D.)--University of Washington, 1981. / Vita. Bibliography: leaves [109]-116.

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