Data/hora: 15/06/2024 22:27:56

Provedor de dados: | 5
País: | France

Título:

Flux sédimentaire en estuaire de Seine : quantification et variabilité multi-échelle sur la base de mesure de turbidité (réseau SYNAPSES)

Sediment fluxes in the Seine estuary : quantification and variability based on turbidity measurements (SYNAPSES monitoring network)

Autores: | Druine, Flavie.
Data: | 2018-06-26
Ano: | 2018
Palavras-chave: | Matière en suspension; Flux de matière en suspension; Réseau de mesures haute-fréquence; Capteurs optiques et acoustiques; Représentativité; Estuaire macrotidal; Estuaire de la Seine; Macrotidal estuary; Seine Estuary; Optical and acoustic sensors; Representativeness; High frequency measurement network; Suspended particulate matter; SPM fluxes.
Resumo: | The dynamics of Suspended Particulate Matter (SPM) in macrotidal estuaries is highly variable both spatially (from the fluvial compartment to the estuary mouth) and temporally (from the second to several years), but it is essential to understand and quantify the sedimentary dynamics of estuarine environments. With the development of high-frequency measurement networks around the world, the main objective of this study is to qualify the turbidity measurements acquired by a high-frequency measurement network (SYNAPSES network) located on the Seine estuary (i) in terms of monitoring the SPM dynamics from the fluvial compartment to the turbidity maximal zone (TMZ) and (ii) in terms of estimation of the SPM fluxes on different spatio-temporal scales of the Seine estuary. Data acquired from the SYNAPSES network and complementary in situ campaigns (81 days of 12 h - OBS-3+/YSI/LISST 100X-C / ADCP 600 kHz) on four stations from the fluvial estuary of the Seine Estuary to the turbidity maximal zone, are an extremely rich and unique dataset on estuarine environments. The variability in the relationship between turbidity measurements [NTU] and SPM concentration measurements [g.L-1] on each campaign, reveals the effect of (i) the internal sensor technology and (ii) the variability of the particle inherent optical properties (median diameter D50, dry density rho and scattering efficiency Qc) on the sensitivity of different optical sensors. The analysis of the in situ and the SYNAPSES data allowed to calibrate the turbidity measurements in mass concentration, with a validated relationship on the annual cycle, specific to each of the stations and reduced uncertainties. After a study of the SYNAPSES station representativeness across the section, the instantaneous fluxes of SPM are estimated (i) from the SPM concentration and liquid flow data acquired by the ADCP on the global section and (ii) from the SPM concentrations of the SYNAPSES network coupled to the hydrodynamic model MARS-3D (estimation of the liquid flow). Comparisons of SPM fluxes in situ to those estimated by the combination SYNAPSES/MARS-3D allow to propose a specific coefficient for each of the SYNAPSES network stations, xith the aim of adjusting the SPM instantaneous fluxes estimated from the SYNAPSES network to the in situ reality, with reasonable uncertainties. the tools and approaches developed in the PhD thesis on the Seine estuary can be applied to other macrotidal estuaries to estimate sedimentary fluxes.
Tipo: | Text
Idioma: | Francês

Identificador:

https://archimer.ifremer.fr/doc/00498/60966/64374.pdf

https://archimer.ifremer.fr/doc/00498/60966/

Editor: | Université de Normandie
Formato: | application/pdf

Fonte:

info:eu-repo/semantics/openAccess

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