The aim of this work is to improve the knowledge of the interconnections between hydro-sedimentary processes and Guianese's coastal morphology evolution, formed by the sedimentary Amazon discharge. This subject follows three spatial scales : the Guianese's Coast, the mud bank and the mudflat. Coastal waves damping by mud and migration process have been studied at the Guianese's Coastal scale. This study also gives a structural vision of subtidal part of banks and highlights the various processes and hydrodynamics conditions needed for sedimentary transport, for two bathymetric areas (> 5 m and < 5 m depth). The morphological evolution of Kourou's mud bank and the associated surfaces of coastal mangrove are also analysed. A link between mangrove colonisation, currents and the mudflat topography is highlighted. This relation allows a discussion about predictive aspect of the mud banks colonisation by mangrove. At the mudflat scale, intertidal part is divided in two areas with different sedimentary dynamic processes : sea front and internals zones. The morphologycal structure and the sedimentary processes of internals zones are analysed. An historical reconstitution method of sedimentary supplies is also proposed. This study underlines morphological coastal changes sensitivity to hydro meteorological forcing and interactions between cohesive sediment and swells which seems to lead the morphological coastal evolution.
