Consulta: subjectFacets:"Vertical migrations"
Registros recuperados: 5
Data/hora: 17/06/2024 01:43:14

New way to estimate efficient use of energy in copepods during migrations
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Petipa, T; Ostrovskaya, N.
It is shown that the energy expenditures on the mechanical movements of copepods depend on the knowledge of character of velocity movements range at active phase. The method of direct estimates of energy expenditures for copepod vertical migration permits to determine more real coefficients of chemical energy utilization on the mechanical work.
Tipo: Text
Palavras-chave: Copepoda; Analytical techniques; Vertical migrations; Locomotion; Energy budget.
Ano: 1984
URL: http://archimer.ifremer.fr/doc/1984/acte-1523.pdf

Vertical migration of zooplankton groups in an Eutrophic bay, Dekhaila harbor, Alexandria, Egypt
Provedor de dados: Ocean Docs: e-repository of  publications
Autores: Abdel-Aziz, N.E.
Diel vertical migration of different zooplankton groups in Dekhaila Harbor was studied monthly from May 2003 to April 2004. Generally, more groups were found in the surface layer (0-10 m.) than the deeper one (10-20 m.). Some zooplankton groups undergo significant vertical migration at certain time of the year, others showed no clear differences in distribution patterns and exhibited no directed movement patterns. Some species stayed a part of the day within certain layer of the water column, others were randomly dispersed in the whole water column during different hours. Responses appear to depend also on the life stages of each zooplankton group, as well as other ecological conditions such as temperature, light and amount of food. Population budget...
Tipo: Journal Contribution
Palavras-chave: Hydrobiology Studies; Zooplankton; Vertical migrations; Ecology; Zooplankton; Http://aims.fao.org/aos/agrovoc/c_15490.
Ano: 2006
URL: http://hdl.handle.net/1834/1455

A drift study of vertical distribution and mortality of Engraulis anchoita eggs and larvae.
Provedor de dados: Ocean Docs: e-repository of  publications
Autores: Sánchez, R.P.; de Ciechomski, J.D.; Lasta, C.A.; Guerrero, R.A.
Lagrangian changes in distribution and survival within an anchovy egg and larvae patch were studied by means of multiple opening/closing sampling following a free drifting buoy. The buoy was equipped with a radar reflector and flashing light, and it was connected to a current cross drogue floating at 15 m depth, which corresponded to the main egg and larvae concentration within the patch. The drifter was launched on the Buenos Aires continental shelf, off Necochea during the spring spawning peak of 1983. Three discrete depths (within, below and above the thermocline)were repeatedly sampled close to the drogue with a Motoda sampler. Egg and larval abundances in the vicinity of the drogue were monitored at 3/4 hour intervals for a period of three days. Each...
Tipo: Journal Contribution
Palavras-chave: Fish larvae; Fish eggs; Vertical migrations; Feeding; Environmental effects; Ichthyoplankton surveys; Vertical distribution; Survival; Abundance; Drifting data buoys; Fishery surveys; Feeding; Fish larvae; Survival; Http://aims.fao.org/aos/agrovoc/c_2838; Http://aims.fao.org/aos/agrovoc/c_2924; Http://aims.fao.org/aos/agrovoc/c_7538.
Ano: 1999
URL: http://hdl.handle.net/1834/1871

El rol del frente de mareas de Península Valdés en el control de la comunidad zooplanctónica
Provedor de dados: Ocean Docs: e-repository of  publications
Autores: Derisio, C.
The Península Valdés tidal front was studied in its rol in the control of the spatial distribution, abundance, assemblages, diversity and life histories of the zooplankton community using samples from two oceanographic surveys. Although the front showed in general high zooplankton abundances, highest values, mainly due to the presence of immature stages of copepods, were recorded in the transitional and stratified zones coinciding with highest values of chlorophyll a. The zooplankton groups showed a distinctive spatial distribution across the front. The results showed that this front did not exert any control on zooplankton composition and diversity, but did on the abundance. In the homogeneous zone the harpacticoid copepods were more abundant, followed by...
Tipo: Theses and Dissertations
Palavras-chave: Zooplankton; Ecological associations; Oceanic fronts; Abundance; Species diversity; Hydrography; Vertical migrations; Copepoda; Cladocera; Marine environment.
Ano: 2012
URL: http://hdl.handle.net/1834/4777

Distribución, áreas de concentración y estructura de la población del bacalao austral (Salilota australis, Gunther 1887)del Atlántico Sudoccidental
Provedor de dados: Ocean Docs: e-repository of  publications
Autores: Perez Comas, J.A.
The "bacalao austral" is a typical fish from the cold water of the Southwest Atlantic and the Southeastern Pacific oceans, whose fishery has not yet developed. In this work, the structure of the concentration areas of summer and winter distribution and other biological items were analyzed, basing on data provening from R/V"Walther Herwig" and R/V"Shinkai Maru", which operated in these waters during 1978/79/. The trophic vertical migrations are common in this species.
Tipo: Journal Contribution
Palavras-chave: Geographical distribution; Size distribution; Sexual maturity; Feeding; Food chains; Length-weight relationships; Population density; Ecological distribution; Vertical migrations; Cod fisheries; Geographical distribution; Feeding; Food chains; Sexual maturity; Population density; Http://aims.fao.org/aos/agrovoc/c_5083; Http://aims.fao.org/aos/agrovoc/c_2838; Http://aims.fao.org/aos/agrovoc/c_3014; Http://aims.fao.org/aos/agrovoc/c_7016; Http://aims.fao.org/aos/agrovoc/c_6112.
Ano: 1980
URL: http://hdl.handle.net/1834/2060