Coastal upwelling, primary production and mussel growth in the Rías Baixas of Galicia

The biomass of pelagic fish in the Coastal Upwelling Domain off the west coast of North America decreased by a factor of 5 in the first half of this century. We assemble several physical and biological time series spanning this period to determine what may have caused this decline in productivity. Based on an observed link between time series of the coastal wind and primary production, we conclude that there was a strong relaxation in wind-induced upwelling and primary production between 1916 and 1942 off southern California. The fact that the individual biomasses of the dominant pelagic fish species tend to rise and fall in phase through the sediment record off southern California is consistent with our belief that these species are responding to a long-period (40–60 yr) oscillation in primary and secondary production, which, in turn, is being forced by a long-period oscillation in wind-induced upwelling. Our extended sardine recruitment time series indicates that there is a nonlinear relationship between Pacific sardine (Sardinops sagax) recruitment and upwelling and suggests that optimal recruitment occurs when the wind speed during the first few months of life averages 7–8 m/s.

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Diatoms Si Uptake Capacity Drives Carbon Export In Coastal Upwelling Systems

10.5194/bg-2015-517 ◽

2016 ◽

Author(s):

F. Abrantes ◽

P. Cermeño ◽

C. Lopes ◽

O. Romero ◽

L. Matos ◽

...

Keyword(s):

Organic Carbon ◽

Primary Production ◽

Coastal Upwelling ◽

Net Primary Production ◽

Regional Scale ◽

Global Scale ◽

Global Ocean ◽

Nutrient Concentrations ◽

Organic Carbon Content ◽

Organic Carbon Burial

Abstract. Coastal upwelling systems account for approximately half of global ocean primary production and contribute disproportionately to biologically driven carbon sequestration. Diatoms, silica–precipitating microalgae, constitute the dominant phytoplankton in these productive regions, and their abundance and assemblage composition in the sedimentary record is considered one of the best proxies for primary production. The study of the sedimentary diatom abundance (SDA) and total organic carbon content (TOC) in the five most important coastal upwelling systems of the modern ocean (Iberia-Canary, Benguela, Peru-Humboldt, California and Somalia-Oman) reveals a global-scale positive relationship between diatom production and organic carbon burial. The analysis of SDA in conjunction with environmental variables of coastal upwelling systems such as upwelling strength, satellite-derived net primary production and surface water nutrient concentrations shows different relations between SDA and primary production on the regional scale. At the global-scale, SDA appears modulated by the capacity of diatoms to take up silicic acid, which ultimately sets an upper limit to global export production in these ocean regions.

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Diatoms Si uptake capacity drives carbon export in coastal upwelling systems

Biogeosciences ◽

10.5194/bg-13-4099-2016 ◽

2016 ◽

Vol 13 (14) ◽

pp. 4099-4109 ◽

Cited By ~ 8

Author(s):

Fatima Abrantes ◽

Pedro Cermeno ◽

Cristina Lopes ◽

Oscar Romero ◽

Lélia Matos ◽

...

Keyword(s):

Organic Carbon ◽

Primary Production ◽

Coastal Upwelling ◽

Net Primary Production ◽

Regional Scale ◽

Global Scale ◽

Global Ocean ◽

Nutrient Concentrations ◽

Organic Carbon Content ◽

Organic Carbon Burial

Abstract. Coastal upwelling systems account for approximately half of global ocean primary production and contribute disproportionately to biologically driven carbon sequestration. Diatoms, silica-precipitating microalgae, constitute the dominant phytoplankton in these productive regions, and their abundance and assemblage composition in the sedimentary record is considered one of the best proxies for primary production. The study of the sedimentary diatom abundance (SDA) and total organic carbon content (TOC) in the five most important coastal upwelling systems of the modern ocean (Iberia–Canary, Benguela, Peru–Humboldt, California, and Somalia–Oman) reveals a global-scale positive relationship between diatom production and organic carbon burial. The analysis of SDA in conjunction with environmental variables of coastal upwelling systems such as upwelling strength, satellite-derived net primary production, and surface water nutrient concentrations shows different relations between SDA and primary production on the regional scale. On the global scale, SDA appears modulated by the capacity of diatoms to take up silicic acid, which ultimately sets an upper limit to global export production in these ocean regions.

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Influence of upwelling events on the estuaries of the north-western coast of the Iberian Peninsula

Marine and Freshwater Research ◽

10.1071/mf12298 ◽

2013 ◽

Vol 64 (12) ◽

pp. 1123 ◽

Cited By ~ 5

Author(s):

I. Alvarez ◽

J. M. Dias ◽

M. deCastro ◽

N. Vaz ◽

M. C. Sousa ◽

...

Keyword(s):

Primary Production ◽

Iberian Peninsula ◽

Biological Diversity ◽

Coastal Upwelling ◽

Western Coast ◽

External Forcing ◽

Ria De Aveiro ◽

The North ◽

Upwelled Water ◽

Ría De Vigo

Coastal upwelling is one of the best studied oceanographic phenomena because of its effects on primary production. The western coast of the Iberian Peninsula has high biological diversity, mainly due to this primary production. In this study, the response of salinity and temperature to the occurrence of upwelling was analysed at the Ria de Vigo– and Ria de Aveiro–ocean boundary over the course of a year. Both systems were influenced by similar external forcing, but the response of thermohaline properties differed. Salinity and temperature were dependent on external forcing throughout the water column at Ria de Aveiro, whereas near-bed measurements revealed the presence of upwelled water at Ria de Vigo. Eastern North Atlantic Central Water was observed during spring–summer (summer) at the southern (northern) mouth of Ria de Vigo, but it was not observed at Ria de Aveiro. This difference may be due to the shallowness and narrowness of the Ria de Aveiro mouth, which can limit the entrance of ocean water. The trends found are unlikely to be unique, suggesting that geomorphologic characteristics of system–ocean boundaries determine how physical processes occurring in adjacent coastal areas impact estuarine properties.

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Significance of nanophytoplankton photosynthesis and primary production in a coastal upwelling system (Ría de Vigo, NW Spain)

Marine Ecology Progress Series ◽

10.3354/meps183013 ◽

1999 ◽

Vol 183 ◽

pp. 13-27 ◽

Cited By ~ 47

Author(s):

GH Tilstone ◽

FG Figueiras ◽

EG Fermín ◽

B Arbones

Keyword(s):

Primary Production ◽

Coastal Upwelling ◽

Nw Spain ◽

Upwelling System ◽

Ría De Vigo

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Phytoplankton photosynthetic efficiency and primary production rates estimated from fast repetition rate fluorometry at coastal embayments affected by upwelling (Rias Baixas, NW of Spain)

Journal of Plankton Research ◽

10.1093/plankt/fbl046 ◽

2006 ◽

Vol 28 (12) ◽

pp. 1153-1165 ◽

Cited By ~ 15

Author(s):

P. Estevez-Blanco ◽

P. Cermeno ◽

M. Espineira ◽

E. Fernandez

Keyword(s):

Primary Production ◽

Repetition Rate ◽

Photosynthetic Efficiency ◽

Production Rates ◽

Coastal Embayments ◽

Nw Of Spain ◽

Fast Repetition Rate Fluorometry ◽

Rías Baixas

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Productivity of the Oceans

Journal of the Fisheries Research Board of Canada ◽

10.1139/f73-345 ◽

1973 ◽

Vol 30 (12) ◽

pp. 2184-2189 ◽

Cited By ~ 3

Author(s):

G. Hempel

Keyword(s):

Primary Production ◽

Mass Culture ◽

Coastal Upwelling ◽

Cold Water ◽

World Ocean ◽

Fish Population ◽

Food Chains ◽

Fish Production ◽

Actual Yield ◽

Oceanic Gyres

The ratio of total world fish landings to annual primary production, about 1:3000, suggests a poor exploitation of the biological productivity of the world ocean. The ratio ranges from 1:100 in the most intensively exploited shelf areas and coastal upwelling regions to beyond 1:100,000 in the central oceanic gyres. Regional differences are a thousand-fold higher in fishing yields than in primary production.The yield differences among areas are caused by three groups of factors: 1, Primary production, which is subject to environmental factors; 2, Length, structure, and transfer efficiency of the food chain, which connects the primary producers with the exploited fish population and determines the ratio between fish production and primary production. Wherever primary production is high, the ratio tends to be favorable, particularly in shelf and upwelling areas. The short pelagic food chains of the cold-water regions lead to rich exploitable resources of pelagic fish, whales, and krill; 3, The rate of exploitation of the fish resources. The ratio between potential production and the actual yield is poor in areas with low fish production, where exploitation is difficult and expensive.Any attempt to increase world fishery yields aims at a change of one of the three groups of factors. Artificial changes in primary production are of local importance only. They are possible through discharge of nutrients and waste energy. Changes in the length and structure of food chains are achieved through a shift of interest to abundant groups of organisms that are closer to primary production. Exploitation of krill and the mass culture of mussels are promising examples. Increases in the exploitation rate can be achieved through better adjustment of fishing to population dynamics of heavily exploited stocks and through extension of pelagic fisheries, particularly in certain parts of the southern hemisphere and the open ocean.

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Herbivorous copepods with emphasis on dynamic Paracalanus quasimodo in an upwelling region

Brazilian Journal of Oceanography ◽

10.1590/s1679-87592016105906401 ◽

2016 ◽

Vol 64 (1) ◽

pp. 67-73 ◽

Cited By ~ 4

Author(s):

Judson da Cruz Lopes da Rosa ◽

Wanda Maria Monteiro-Ribas ◽

Lohengrin Dias de Almeida Fernandes

Keyword(s):

Primary Production ◽

Coastal Upwelling ◽

Deep Ocean ◽

Organic Production ◽

Rapid Response ◽

Cabo Frio

Abstract Coastal upwelling is known to transfer the nutrient-rich water from the deep ocean to the surface, which benefits primary production and consequently increases local organic production. Cabo Frio is favored by the phenomenon and copepods are one of the groups most benefited. According to the results presented here, the higher abundances of Pacalanus quasimodo relative to other species are due to its rapid response to upwelling-dependent blooms. Therefore this study aims to assess the herbivory and dynamics of many copepod populations with emphasis on P. quasimodo. The results showed that temperature influences primary production, which in turn benefits the seston biomass (R2 = 0.65, p = 0.008). The dominance of P. quasimodo was due to its emphasis on herbivory (R2 = 0.83) and lead to a decrease in the planktonic diversity (R2 = 0.63, p = 0.002). Our results revealed that predation by carnivorous copepods, like Corycaeus spp. and Oncaea spp. is the main opposing factor affecting P. quasimodo dominance. (R2 = 0.70, p = 0.004; βpredators = 0.41, p = 0.04).

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