Skip to Main content Skip to Navigation
Theses

Dynamique morphosédimentaire d'un segment côtier sableux: du Lycée Léon Mba (Libreville) à La Sablière (Baie d'Akouango)

Abstract : With regard to coastal erosion issue and its damages on socio-economic activities on Libreville and Akanda beaches, the morphosedimentary dynamic of intertidal beach was analyzed from hotel Dialogue to Akouango Village in the northern bay of Akouango. This study highlighted several morphosedimentary processes. To achieve this general goal, the methodological approach combines intertidal beach cross-shore profile analyses, shoreline motion analyses, and superficial sediment analyses. The cross-shore beach profile monitoring presents a global negative sedimentary balance between -18,8 m3/m and +11,08 m3/m . Between 1977 and 2013, shoreline motion reveals variation rates from -2,07 m/year to +1.78 m/year. These rates correspond to 83% eroded beaches against 17% accreted. Grainsize analyses show that 28% of samples are unimodal, 51% are bimodal and 21 % are trimodal, providing information about sediment sorting processes by coastal current during transport and sedimentation phases. Studied beaches are characterized by a sedimentary deficit due to a weakness of sediment supply by water bodies and coastal currents. Given this, sediments found on intertidal beaches come mainly from the remodeling from near shore and upper beach. The morphosedimentory dynamic of intertidal beach is influenced by the combination of natural (climatic seasonal variations) and anthropogenic factors (great human influences on coastal processes) on studied beaches. Finally, a better knowledge of coastal dynamic provides policy makers with tools for an integrated coastal management.
Complete list of metadatas

Cited literature [20 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-01772394
Contributor : Vivino Max Thierry Mouyalou <>
Submitted on : Friday, April 20, 2018 - 11:49:17 AM
Last modification on : Thursday, May 3, 2018 - 1:24:28 AM
Long-term archiving on: : Tuesday, September 18, 2018 - 5:57:29 PM

File

MOUYALOU_VIVINO_M.T._2017_THES...
Files produced by the author(s)

Identifiers

  • HAL Id : tel-01772394, version 1

Collections

Citation

Vivino Max Thierry Mouyalou. Dynamique morphosédimentaire d'un segment côtier sableux: du Lycée Léon Mba (Libreville) à La Sablière (Baie d'Akouango). Géographie. Université Omar Bongo, Libreville., 2017. Français. ⟨tel-01772394⟩

Share

Metrics

Record views

164

Files downloads

1576