Tidal-fluvial interaction in the Guadalquivir River Estuary: Spatial and frequency-dependent response of currents and water levels

2017 ◽  
Vol 122 (2) ◽  
pp. 847-865 ◽  
Author(s):  
M. A. Losada ◽  
M. Díez-Minguito ◽  
M. Á. Reyes-Merlo
1982 ◽  
Vol 1 (18) ◽  
pp. 148
Author(s):  
G.A.W. Fromme

During the flood year of 1981 the "Bot River Vlei", one of the largest lagoons in the south-western Cape of the Good Hope was opened to the sea by two artificial breachings of the sand bar which were aimed at lowering the excessively high water levels in the lagoon, and at the re-establishment of estuarine conditions. The Coastal Engineering and Hydraulics Division of the National Research Institute for Oceanology of the CSIR surveyed and monitored the hydrological and sedimentological events in the Bot River lagoon and at the mouth channels in an attempt to formulate a future viable management policy, which had to take into account the conflicting interests of the defenders of continued artificial breachings and of those who advocate conditions of a closed estuary which will eventually change into a coastal freshwater lake.


Hydrobiologia ◽  
2007 ◽  
Vol 587 (1) ◽  
pp. 125-136 ◽  
Author(s):  
Carlos Fernández-Delgado ◽  
F. Baldó ◽  
C. Vilas ◽  
D. García-González ◽  
J. A. Cuesta ◽  
...  

Water ◽  
2018 ◽  
Vol 10 (2) ◽  
pp. 110 ◽  
Author(s):  
Zakir Syed ◽  
Gyewoon Choi ◽  
Seongjoon Byeon

2021 ◽  
pp. 1-6
Author(s):  
Willian Melo ◽  
José Pinho ◽  
Isabel Iglesias ◽  
Ana Bio ◽  
Paulo Avilez-Valente ◽  
...  

The knowledge of physical, biological, and chemical estuarine processes and how they are affected by climate change conditions is essential for improving estuarine management. A common methodological approach for studying these complex processes is based on the implementation of numerical models supported by field data as bathymetry, sediment characteristics, flow discharges, current velocities, and sea water levels. This work is based on the implementation of a numerical model of the Minho River estuary using the Delft3D software. This model is able to simulate hydrodynamic and morphodynamic processes for different time scales. It was calibrated using the OpenDA tool, which automatically determines some of the models’ parameters, such as the tidal constituents and the roughness coefficient, aiming to minimize the error between observed data and simulated results. Different scenarios were considered to assess the effects of climate change, according to the 5th Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). Results showed that the elevation in the estuary mouth can reach 77 cm, depending on the considered scenario. It was also determined that floods are the main sediment transport driver along the estuary, intensifying the accretion processes. Furthermore, the sea-level rise reduces the amount of transported sediments to the coastal platform, increasing the erosion risk in this area and increasing the accretion inside the estuary.


2013 ◽  
Vol 1 ◽  
pp. 24005
Author(s):  
J. A. López-López ◽  
C. Mendiguchía ◽  
M. García-Vargas ◽  
C. Moreno

2015 ◽  
Vol 39 (3) ◽  
pp. 605-620 ◽  
Author(s):  
Enrique M. Padilla ◽  
Manuel Díez-Minguito ◽  
Miguel Ortega-Sánchez ◽  
Miguel A. Losada

2017 ◽  
Vol 81 (1) ◽  
pp. 19 ◽  
Author(s):  
Rafael Bañón ◽  
Alberto Arias ◽  
Diego Arana ◽  
Jose A. Cuesta

Cynoscion is a genus of fish in the family Sciaenidae from the Atlantic and Pacific American coasts that is important in recreational and commercial fisheries. Morphological analysis identifies a species inhabiting the Gulf of Cádiz (southern Spain) as the weakfish, Cynoscion regalis, a native of the northwest Atlantic. This finding is also confirmed by molecular identification using 16S and Cox1genes. Based on the examination of a previous manuscript, the assignation of this species to the spotted seatrout, Cynoscion nebulosus, is considered a misidentification. C. regalis has been reported in the area since 2011 and is now considered an established species that is distributed along the Guadalquivir River estuary and is a target of local artisanal fisheries. The pathway of introduction is unknown, but possible mechanisms are considered, of which ballast water seems to be the most plausible. A revision of non-native sciaenids also found in European waters is carried out. The ecological impact of weakfish on the local fish community is still unknown and should be object of future studies.


2012 ◽  
Vol 42 (3) ◽  
pp. 352-369 ◽  
Author(s):  
Nickitas Georgas

Abstract Seasonal episodes of significant tidal damping (reductions of tidal amplitudes as much as 50%) and tidal modulation were observed in the Hudson River estuary in the course of three consecutive winters from multiple tide gages. Through comparisons with United States Coast Guard ice reports, it was hypothesized that these events correspond with an increase in ice concentration and the development of a seasonal ice field within the upper 170 km of the tidal Hudson north of Peekskill, New York. Using stationary (tidal harmonic) and nonstationary (wavelet) analyses as well as numerical modeling, it is shown that under-ice friction is the primary cause of the observed modulations in tidal circulation (water levels and currents) throughout the 240-km-long estuary. Upstream of the ice field edge at Peekskill, depth-averaged tidal currents are greatly reduced under the ice cover through first-order damping, and vertical current profiles under the ice become parabolic. Tidal ranges increase near the edge of the ice field, and, south of that, on Manhattan’s western shores, currents increase because of tidal wave reflection. These amplified currents create stronger vertical mixing leading to a less stratified estuary and decreasing salt front intrusion. At the other end, near Troy, tidal flows become smaller relative to the river’s streamflow, leading to increased ebb predominance and ebb-directed flows down to the port of Albany. Also, the increased friction leads to a higher sea level setup there. During such episodes, astronomical tide–based and operational forecast model predictions that neglected ice are severely compromised.


Hydrobiologia ◽  
2014 ◽  
Vol 744 (1) ◽  
pp. 15-33 ◽  
Author(s):  
José Pedro Cañavate ◽  
Carmen Pérez-Gavilan ◽  
Narciso Mazuelos ◽  
Manuel Manchado

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