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Showing 1 to 20 of 209 for “"Benguela"”.
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Annual cycle of the Benguela Jet
The Benguela Jet is a north-westward flowing current in the southern Benguela region. It is known to have an important influence on the fish recruitment yet little is known about the physical properties of the jet. In this study the ability of satellite data (SST and altimetry) to resolve the Jet …
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Wind-stress variability over the Benguela upwelling system
Regional wind-stress variability over the Benguela Upwelling System is described using 16 months (01 August 1999 29 November 2000) of satellite derived QuikSCA T wind data. The QuikSCA T data are compared to the climatologies presented by Kamstra (1985) and Bakun and Nelson (1991), as well as the …
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Retention processes in the Southern Benguela upwelling system
The Benguela Upwelling System is one of four major Eastern Boundary Upwelling Systems (EBUS) in the global ocean. Here, equatorward winds drive the upwelling of cold, deep, nutrient-rich waters along the coast, which drives high levels of biological productivity. A consequence of this high …
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Bacterioplankton dynamics in the Southern Benguela upwelling region
The role of heterotrophic bacteria in the carbon and nitrogen flux of the pelagic food web was investigated during laboratory and field-based studies of the temporal development of the planktonic community after upwelling. Bacterial community structure, activity and production were closely coupled …
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Lateral carbon export from the southern Benguela upwelling system
… from the continental shelf of the southern Benguela upwelling system to the open ocean. The flux is potentially important because the Benguela is one of the most productive and biogeochemically active ecosystems in the global ocean. Furthermore, a significant fraction of oceanic carbon …
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Lateral carbon export from the southern Benguela upwelling system
… from the continental shelf of the southern Benguela upwelling system to the open ocean. The flux is potentially important because the Benguela is one of the most productive and biogeochemically active ecosystems in the global ocean. Furthermore, a significant fraction of oceanic carbon …
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Bacterial populations and their activity in the Benguela upwelling system
An investigation of variability in hydrological and bacterial parameters at a fixed coastal station (Oudekraal. Cape Peninsula 33°59'S 17°21'E) showed that bacterial populations varied in numbers and biomass on both a short term (daily) and seasonal basis in response to changes in hydrological …
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Modelling Benguela niños using the regional oceanic modeling system (ROMS)
… forcing in the western equatorial Atlantic and Benguela Niños/Niñas? Thirdly, what is the impact of these events on the equatorial Atlantic Ocean SST and circulation patterns? The results obtained suggest that the model is very sensitive to different wind stress forcing, particularly in respect …
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The sea surface heat balance in the Benguela upwelling region
The surface heat balance of the Benguela upwelling area on the west coast of southern Africa is analysed. Measurements of the components of the heat balance were made in the St Helena Bay area from 14-21 October 1986. Additional long-term data was obtained from Alexander Bay and Cape Town. An …
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Specific applications of satelite remote sensing to the Benguela ecosystem
… to investigate the upper layer dynamics of the Benguela ecosystem in more detailed space and time scales than previously undertaken. The standard for SeaWiFS bio-optical algorithms and processing parameters are not ideal for the highly productive Benguela waters. Hence, a detailed investigation …
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Phytoplankton growth and zooplankton grazing in the southern Benguela current
… mesozooupwelled waters of the southern Benguela Current by means of an electronic counting and sizing technique (Coulter counter). A feasibility study was initiated to test the accuracy of the Coulter counter (Model TAII) in estimating phytoplankton size and biomass in fresh and …
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Reconstructing the Benguela ecosystem for a time before man's intervention
… since fishing and exploitation began in the Benguela, in terms of both structure and function. This will be investigated using Ecopath with Ecosim (EwE) There are currently available, models of the Benguela ecosystem based on modern catch and biomass data that cover the period from the 1970, …
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Egg cannibalism by anchovy in the Southern Benguela Current Region
Samples of adult anchovy and plankton were collected on Sea Fisheries Research Institute R.S. Africana 1984-1985 anchovy spawner biomass estimation cruises. A total of 40 sets of anchovy samples of 30 fish each and 40 plankton samples were taken roughly at the same time within an area of intensive …
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Equilibrium dynamics of the Benguela system : a numerical modelling approach
… conditions and seasonal variations of the Benguela system, including both the large-scale flow regime as well as the coastal upswelling regime. A shelf-edge poleward flow exists in the northern Benguela region and is driven primarily by the wind-stress curl via the Sverdup relation. As …
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Fish spawning strategies in the variable southern Benguela Current region
… surveyed at monthly intervals in the southern Benguela. Current system between August 1977 and August 1978. Plankton was collected at each station by means of a double oblique tow behind the ship at 2 knots down to 100m or 5m off the bottom. Plankton displaced volume was determined and all fish …
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Coastal climate change and variability in the Benguela current system
… long-term change and decadal variability in the Benguela Upwelling System and study the possible mechanisms behind these changes. The Benguela Upwelling System is one of the four most productive fisheries areas in the world, and it is therefore important to understand the mechanisms leading to …
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Bio-optical investigation of phytoplankton production in the southern Benguela ecosystem
… models for the estimation of PP in the southern Benguela ecosystem, and to investigate the photophysiological responses of phytoplankton to changes in environmental conditions.
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Shelf biogeochemical interactions and feedback processes in the Benguela upwelling system
… Flux Model) NEMO-BFM (1D) are applied in the Benguela upwelling system to understand biogeochemical interactions and their related feedback processes. The models are formulated differently but achieve similar objectives with respect to the physics and biogeochemistry. The BioEBUS model is used …
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Phytoplankton physiology in a nearshore region of the southern Benguela current
During the summer of 1978-79 diatoms dominated the communities from October to January but microflagellates were dominant in February and March. Low concentrations of ATP, chlorophyll a protein and carbohydrate were measured in Type 1 water with protein/carbohydrate ratios being )1. In Type 2 water …
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Analysis of variable scatterometer wind fields in the Benguela upwelling region
The dissertation seeked to understand the effectiveness of satellite based data collection of wind fields along the west coast of southern Africa, pertaining to particular synoptic atmospheric systems. A comparison between data from two automatic coastal weather stations and measurements obtained …
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