Tidal and seasonal carbon and nutrient dynamics of the Guadalquivir estuary and the Bay of Cádiz (SW Iberian Peninsula)

Abstract. To study the effects of the physical environment on carbon and nutrient cycle dynamics on the north-eastern shelf of the Gulf of Cádiz, changes in currents, tides, salinity, temperature, carbon system parameters (fugacity of CO2 (fCO2), dissolved organic carbon, dissolved inorganic carbon (DIC) and pH) and other related parameters(dissolved oxygen, total dissolved nitrogen (TDN), nutrients and suspended particulate matter) were measured in transects across the Guadalquivir estuary and Bay of Cádiz mouths. The main objective of this study is to investigate the influence of these inner ecosystems on the carbon and nutrient distributions on the adjacent continental shelf. Three cruises were undertaken in June 2006, November 2006 and February 2007. During the whole study period, Guadalquivir estuary exported components at a rate of 3 Gmol of SiO2, 4 Gmol of DIN, 3 Gmol of TDN, 31 Gmol of DOC and 604 Gmol of DIC per year. On the other hand, Bay of Cádiz imported 3 Gmol of SiO2, 1 Gmol of DIN, 2 Gmol of TDN, 33 Gmol of DOC and 562 Gmol of DIC per year. Diurnal variability of fCO2 could have a potentially important implication on the estimate of air–sea CO2 fluxes. Tides influence velocity and transport of carbon and nutrients: we found statistically significant differences (p < 0.0001, n = 220) between the flood tide (the mean velocity was 4.85 cm s–1) and the ebb tide (the mean velocity was −5.67 cm s–1). Biological activity and diurnal changes have also an important role on the carbon and nutrient dynamics. Seasonal carbon and nutrient variations were found. During June, both systems were exporting components to the adjacent continental shelf of the Gulf of Cádiz, whereas in February both systems were importing. Monthly studies should be undertaken to completely understand this dynamic system.

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Tidal and seasonal carbon and nutrients dynamics of the Guadalquivir Estuary and the Bay of Cádiz (SW Iberian Peninsula)

Biogeosciences Discussions ◽

10.5194/bgd-9-14537-2012 ◽

2012 ◽

Vol 9 (10) ◽

pp. 14537-14558

Author(s):

M. Ribas-Ribas ◽

L. I. Carracedo ◽

E. Anfuso ◽

J. M. Forja

Keyword(s):

Continental Shelf ◽

Dissolved Inorganic Carbon ◽

Gulf Of Cadiz ◽

Diurnal Variability ◽

Guadalquivir Estuary ◽

The North ◽

Total Dissolved Nitrogen ◽

Gulf Of Cádiz ◽

Bay Of Cadiz ◽

Bay Of Cádiz

Abstract. To study the effects of the physical environment on carbon and nutrients cycles dynamics in the north eastern shelf of the Gulf of Cádiz, changes in currents, tides, salinity, temperature, carbon system parameters (fugacity of CO2 (fCO2), dissolved organic carbon, dissolved inorganic carbon and pH) and others related (dissolved oxygen, total dissolved nitrogen, nutrients and suspended particulate matter) were measured in transects across the Guadalquivir Estuary and Bay of Cádiz mouths. Thus, the main objective of this study is to investigate the influence of these inner ecosystems on the carbon and nutrient distributions in the adjacent continental shelf. Three cruises have been undertaken in June 2006, November 2006 and February 2007, each one covering one complete tidal cycle during June, both systems were exporting components to the adjacent continental shelf of the Gulf of Cádiz. In an annual scale, Guadalquivir Estuary exported components while Bay of Cádiz imported them. Diurnal variability of fCO2 could have a potentially important implication on the estimate of air-sea CO2 fluxes. Monthly studies should be undertaken to completely understand this dynamic system.

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Methane dynamics in the coastal – Continental shelf transition zone of the Gulf of Cadiz

Estuarine Coastal and Shelf Science ◽

10.1016/j.ecss.2020.106653 ◽

2020 ◽

Vol 236 ◽

pp. 106653 ◽

Cited By ~ 1

Author(s):

A. Sierra ◽

D. Jiménez-López ◽

T. Ortega ◽

M.C. Fernández-Puga ◽

A. Delgado-Huertas ◽

...

Keyword(s):

Continental Shelf ◽

Transition Zone ◽

Gulf Of Cadiz ◽

Gulf Of Cádiz ◽

Methane Dynamics

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Reproductive biology of Eledone moschata (Cephalopoda: Octopodidae) in the Gulf of Cádiz (south-western Spain, ICES Division IXa)

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315404010690h ◽

2004 ◽

Vol 84 (6) ◽

pp. 1221-1226 ◽

Cited By ~ 21

Author(s):

Luis Silva ◽

Fernando Ramos ◽

Ignacio Sobrino

Keyword(s):

Reproductive Period ◽

Female Dominance ◽

Gulf Of Cadiz ◽

Annual Life Cycle ◽

Gulf Of Cádiz ◽

Mean Size ◽

The Mean ◽

Western Spain ◽

By Catch ◽

Condition Indices

Reproductive aspects of Eledone moschata from the Spanish waters of the Gulf of Cádiz are reported for the first time. The species is relatively abundant over the continental shelf and it is caught as by-catch by the bottom-trawl fleet. Monthly samplings throughout one annual life-cycle showed a sex ratio with a female dominance (0·45:1). A four stage maturity scale was used for both sexes. The reproductive period was determined from monthly evolution of these stages as well as that of several maturity and condition indices. The breeding season extended from October to June, with spawning peaks in October and March–May, the second one being more important. Length and weight at maturity (mantle length50, body weight50) were estimated at 7·8 cm and 97 g in males, and at 12·2 cm and 274 g in females, respectively. Total fecundity, estimated from 52 mature females, was 443·5±154·4 oocytes on average. The mean size of mature oocytes and the mean length of mature spermatophore in mature females and males was 10·24 mm (±1·07) and 13·88 mm (±1·60), respectively.

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Validation of CryoSat-2 SIRAL sea level data in the eastern continental shelf of the Gulf of Cadiz (Spain)

Advances in Space Research ◽

10.1016/j.asr.2017.10.042 ◽

2018 ◽

Vol 62 (6) ◽

pp. 1405-1420 ◽

Cited By ~ 6

Author(s):

J. Gómez-Enri ◽

S. Vignudelli ◽

P. Cipollini ◽

J. Coca ◽

C.J. González

Keyword(s):

Continental Shelf ◽

Sea Level ◽

Gulf Of Cadiz ◽

Level Data ◽

Gulf Of Cádiz

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The influence of the Guadalquivir river on spatio-temporal variability in the pelagic ecosystem of the eastern Gulf of Cádiz

Mediterranean Marine Science ◽

10.12681/mms.844 ◽

2014 ◽

Vol 15 (4) ◽

pp. 721 ◽

Cited By ~ 18

Author(s):

I. CABALLERO ◽

E. P. MORRIS ◽

L. PIETRO ◽

G. NAVARRO

Keyword(s):

Temporal Variability ◽

Phytoplankton Biomass ◽

Phytoplankton Bloom ◽

Light Limitation ◽

Gulf Of Cadiz ◽

Phytoplankton Blooms ◽

Pelagic Ecosystem ◽

Guadalquivir Estuary ◽

Gulf Of Cádiz ◽

Spatio Temporal

This study examines the spatio-temporal variability of the turbidity plume and phytoplankton biomass (in terms of chlorophyll) in the marine region influenced by the Guadalquivir estuary using ocean colour images over a period of 11 years (2003-2013). The area of the turbidity plume was calculated using water-leaving radiance at 555 nm (nLw555). Climatologic and monthly averages showed recurrent high nLw555 levels in winter and high chlorophyll in spring. Similar variability was confirmed by Empirical Orthogonal Function (EOF) analysis of 8-day composite images, illustrating the existence of different regions with similar behavior. The first EOF mode explained 60.7% and 31% of the variability in nLw555 and chlorophyll, respectively, and was associated with enhanced Total Suspended Solids (TSS) in autumn-winter and phytoplankton blooms in winter-spring periods. The results confirmed that the development of the turbidity plume and subsequent phytoplankton blooms were strongly regulated by river discharges and precipitation. Indeed, interannual variation in nLw555 was consistent with changes in the large-scale climate index, the North Atlantic Oscillation, a proxy for regional rainfall patterns. In the case of phytoplankton biomass, the second EOF mode revealed differentiation between offshore and nearshore areas, the latter characterized by delayed development of phytoplankton bloom due to light limitation by high TSS. This suggests that the stability of the water column, via its influence on phytoplankton light-limitation, influenced also the timing and magnitude of phytoplankton bloom events. The dynamic of the Guadalquivir estuary turbidity plume is a crucial factor for the pelagic ecosystem of the Eastern Gulf of Cadiz, governing phytoplankton productivity.

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Utility of clay Minerals in the Determination of Sedimentary Transport Patterns in the Bay of Cadiz and the Adjoining Continental Shelf (SW-Spain)

Geodinamica Acta ◽

10.3166/ga.21.259-272 ◽

2008 ◽

Vol 21 (5-6) ◽

pp. 259-272 ◽

Cited By ~ 1

Author(s):

Mohammed Achab ◽

José Manuel Gutierrez-Mas ◽

Francisco Lòpez Aguayo

Keyword(s):

Continental Shelf ◽

Clay Minerals ◽

Sw Spain ◽

Bay Of Cadiz ◽

Transport Patterns ◽

Bay Of Cádiz

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Clay minerals in recent sediments of the continental shelf and the Bay of Cádiz (SW Spain)

Clay Minerals ◽

10.1180/claymin.1997.032.4.02 ◽

1997 ◽

Vol 32 (4) ◽

pp. 507-515 ◽

Cited By ~ 5

Author(s):

J. M. Gutierrez-Mas ◽

A. Lopez-Galindo ◽

F. Lopez-Aguayo

Keyword(s):

Continental Shelf ◽

Clay Minerals ◽

Sediment Supply ◽

Sw Spain ◽

Mineral Associations ◽

Hydrodynamic Processes ◽

Bay Of Cadiz ◽

Recent Sediments ◽

Muddy Sediments ◽

Bay Of Cádiz

AbstractThe distribution of clay minerals in recent sediments on the continental shelf and in the Bay of Cádiz has been analysed as part of a wider study of sedimentary exchange between the continent and the continental margin. The clay minerals included in the muddy sediments consist mainly of illite, kaolinite, smectite, randomly mixed-layered illite-smectite, chlorite, vermiculite and randomly mixed-layered illite-chlorite. Distribution of the minerals indicates that inheritance from the adjacent continental areas is the most important process involved.The relations between the clay minerals were established by Q-mode and R-mode factor analysis. The main clay mineral associations are: (1) illite-kaolinite, (2) smectite-random mixed-layered illitesmectite, and (3) kaolinite-random mixed-layered illite-smectite-vermiculite. The main sources of sediment supply to the continental shelf are the Guadalquivir and Guadiana rivers. Sediment from these rivers and from the rivers flowing into the Bay of Cádiz (mainly the Guadalete) is transported to the part of the shelf outside the bay by ebb-tide currents. The path of this outflow to the continental shelf, where the sediment is partially deposited, is influenced by the morphology of the coast and by hydrodynamic processes.

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