Hydro-sedimentary processes of a shallow tropical estuary under Amazon influence. The Mahury Estuary, French Guiana

Orseau, Sylvain; Lesourd, Sandric; Huybrechts, Nicolas; Gautier, Antoine

doi:10.1016/j.ecss.2017.01.011

Cited by 20 publications

(19 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Such tropical estuaries are commonly bordered by mangroves that trap sediments [6][7][8][9] and affect flushing rates [10,11], thus contributing to the dynamics of the ETM. Unfortunately, studies dealing with the ETM in tropical estuaries are relatively scarce when compared to those devoted to the study of estuarine hydrodynamics [12][13][14][15][16].…”

Section: Introductionmentioning

confidence: 99%

“…These processes are of biological importance, as they are associated with rapid and large-scale mangrove colonization, creating an ecotope for fish and shrimp development, but they also affect human activities such as access to river ports and maritime traffic and access to beaches. During such phases, mud banks also provide an important external source of sediments, which, under the combined effect of tidal currents and trade-wind waves, can be resuspended and intrude into the numerous estuaries [14] lining the humid tropical coasts of the Guianas. The ETM can, thus, be significantly modified during these phases by the presence of mud banks, with navigation channels behaving as mud traps [30].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Dynamics of the Estuarine Turbidity Maximum Zone from Landsat-8 Data: The Case of the Maroni River Estuary, French Guiana

et al. 2020

Self Cite

View full text Add to dashboard Cite

The estuarine turbidity maximum (ETM) zone occurs in river estuaries due to the effects of tidal dynamics, density-driven residual circulation and deposition/erosion of fine sediments. Even though tropical river estuaries contribute proportionally more to the sediment supply of coastal areas, the ETM in them has been hardly studied. In this study, surface suspended particulate matter (SPM) determined from OLI (Operational Land Imager)-Landsat 8images was used to gain a better understanding of the spatio-temporal dynamics of the ETM of the tropical Maroni estuary (located on the Guianas coast, South America). A method to estimate the remotely-sensed ETM location and its spatiotemporal evolution between 2013 and 2019 was developed. Each ETM was defined from an envelope of normalized SPM values > 0.6 calculated from images of the estuary. The results show the influence of the well-marked seasonal river discharge and of tides, especially during the dry season. The ETM is located in the middle estuary during low river-flow conditions, whereas it shifts towards the mouth during high river flow. Neap–spring tidal cycles result in a push of the ETM closer to the mouth under spring-tide conditions or even outside the mouth during the rainy season. An increase in SPM, especially since 2017, coincident with an extension of the ETM, is shown to reflect the periodic influence of mud banks originating from the mouth of the Amazon and migrating along the coast towards the Orinoco (Venezuela). These results demonstrate the advantages of ocean color data in an exploratory study of the spatio-temporal dynamics of the ETM of a tropical estuary, such as that of the Maroni.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Dynamics of the Estuarine Turbidity Maximum Zone from Landsat-8 Data: The Case of the Maroni River Estuary, French Guiana

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…To date, there have been very few studies on estuaries located on the Northern coast of South America [15][16][17], as most studies have focused on the coastal area under the influence of the Amazon River ( [18,19] and references therein). In fact, in the Maroni estuary, the focus of research has been the geochemistry of suspended matter and bottom deposits [20] with the first observations on hydro-sedimentary dynamics conducted very recently [21].…”

Section: Introductionmentioning

confidence: 99%

Intratidal and Subtidal Circulation in a Tropical Estuary during Wet Season: The Maroni, French Guiana

Ross

Sottolichio

Maury

et al. 2019

JMSE

Self Cite

View full text Add to dashboard Cite

Observations of water level, current velocity, river discharge, wind and salinity were collected in the Maroni estuary, on the border of French Guiana and Suriname during the wet season of 2018 to explore subtidal circulation patterns. Measurements are complimented by the application of analytical models with an aim to diagnose forcing mechanisms responsible for producing subtidal flows during the day of data collection and to extrapolate these findings to other time periods with variable wind and river forcing. Subtidal along-channel flows were found to be dominated by river discharge, with seaward directed velocities found throughout the channel section reaching 40 cm s − 1 . This pattern was altered with strong southwesterly winds, which produced and inverse gravitational circulation pattern despite the elevated river discharge. Secondary, or cross-channel flows, displayed a three-layer vertical structure in the main channel due to a combination of channel curvature and tidal asymmetry in the lateral baroclinic pressure gradient. The pressure gradient was produced by a salinity intrusion front that only manifested in the channel during flood tide. This is the first comprehensive study of tidal and subtidal flow dynamics in the Maroni estuary.

show abstract

“…Winds are mainly active from December to May, with low to moderate speeds (mean annual average: 5m.s -1 ), and blow predominantly from the northeast. The Mahury has an annual fresh water discharge of 2.94x10 9 m 3 for 2014 and seasonal values averaged J o u r n a l P r e -p r o o f around 31 m 3 .s -1 during the dry season and 170 m 3 .s -1 during the rainy season (Orseau et al, 2017).…”

Section: Study Areamentioning

confidence: 99%

Decadal-scale morphological evolution of a muddy open coast.

Orseau

Zorrilla²,

Huybrechts

et al. 2020

Marine Geology

Self Cite

View full text Add to dashboard Cite

show abstract

Hydro-sedimentary processes of a shallow tropical estuary under Amazon influence. The Mahury Estuary, French Guiana

Cited by 20 publications

References 43 publications

Dynamics of the Estuarine Turbidity Maximum Zone from Landsat-8 Data: The Case of the Maroni River Estuary, French Guiana

Dynamics of the Estuarine Turbidity Maximum Zone from Landsat-8 Data: The Case of the Maroni River Estuary, French Guiana

Intratidal and Subtidal Circulation in a Tropical Estuary during Wet Season: The Maroni, French Guiana

Decadal-scale morphological evolution of a muddy open coast.

Contact Info

Product

Resources

About