Suspended Particulate Matter Formation And Accumulation In The Delta

Abstract

Coastal areas are subjected to major anthropogenic influences, as they are traditionally economically important regions, which is reflected by the presence of harbours, especially at river mouths. The Dutch coastal area is influenced by the discharge of fresh water from the Rhine river that creates the Rhine Region Of Freshwater Influence (Rhine -ROFI). There is also an additional sediment supply by alongshore transport resulting from seabed or coastal erosion. The transport of sediment is primarily driven by hydrodynamics. River plumes that pass the estuaries reaching the coastal areas play an important role in terms of Suspended Particulate Matter (SPM) formation and transport, especially in ROFI regions. SPM is defined as a suspension of microscopic particles consisting of clay minerals (sediment) aggregated or not with organic matter. Aggregated particles (flocs) are composed of different fractions of inorganic and organic parts. Flocculation and aggregation is greatly promoted in saline environment, and sediment particles are thereby more prone to flocculate in coastal regions, leading to different transport, settling, deposition and erosion dynamics as compared to freshwater conditions. The general aim of this thesis is to present a flocculation model that properly predicts SPM formation by flocculation in space and time that can easily be implemented in numerical sediment transport models.