Distinctive sedimentary processes on two contrasting tidal flats of the Yellow River Delta

Coastal tidal flats provide valuable ecosystems, but are highly sensitive to tidal dynamics, sea-level rise, and human activities. Tidal inundation depth and frequency are known to affect tidal flat morphodynamics. However, the causes, processes and extent remain uncertain, particularly given the associated changes in sediment availability. In...

Modelling mangrove-mudflat dynamics with a coupled individual-based-hydro-morphodynamic model

As climate-change-driven extremes potentially make coastal areas more vulnerable, mangroves can help sustainably protect the coasts. There is a substantial understanding of both mangrove dynamics and hydro-morphodynamic processes. However, the knowledge of complex eco-geomorphic interactions with physical-environmental stressors remains...

Using salt marshes for coastal protection: Effective but hard to get where needed most

Salt marshes fronting coastal structures, such as seawalls and dikes, may offer important ecosystem-based coastal defence by reducing the wave loading and run-up levels during storms. We question (i) how the long-term salt marsh development in the Dutch Wadden Sea relates to the tidal-flat foreshore bathymetry and (ii) how the wave run-up...

Impact of Reduced Fluvial Sediment Supply on Saltwater Intrusion in the Yangtze Estuary

A decline of the fluvial sediment supply leads to coastal erosion and land loss. However, the fluvial sediment load may influence not only coastal morphodynamics but also estuarine hydrodynamics and associated saltwater intrusion. Previous studies revealed that suspended sediments influence estuarine hydrodynamics through various flow...

Cellular automaton modelling of the effects of buildings on aeolian bedform dynamics

Buildings affect aeolian sediment transport and bedform development in sandy environments. Cellular automaton (CA) models have, however, only been used to simulate natural bedform dynamics. This study extends a well-known aeolian CA model to include sediment dynamics around buildings, and uses this model to explore the interaction of building...

Anthropogenic effects on the hydro-morphological development of turbid estuaries

Estuarine sediment dynamics involves estuarine hydrodynamics, sediment transport, and morphology, and strongly influence ecosystem dynamics and sustainability. In the current geological epoch, referred to as the Anthropocene, human activities are exerting increasing impacts on the environment on all scales, changing hydrodynamics, sediment...

Lateral Flows and Sediment Dynamics in a Large Engineered Estuary

Estuaries are partially enclosed water bodies where river water mixes with sea water. Estuaries provide important ecological functions which are strongly regulated by estuarine hydrodynamics and sediment dynamics, and also by human interventions. Sustainable management of such systems therefore requires a thorough understanding of the interplay...

Beach-dune modelling in support of Building with Nature for an integrated spatial design of urbanized sandy shores

The long-term physical existence of sandy shores critically depends on a balanced sediment budget. From the principles of Building with Nature it follows that a sustainable protection of sandy shores should employ some form of shore nourishment. In the spatial design process of urbanized sandy shores, where multiple functions must be integrated,...

Characterizing the Composition of Sand and Mud Suspensions in Coastal and Estuarine Environments Using Combined Optical and Acoustic Measurements

Quantifying and characterizing suspended sediment is essential to successful monitoring and management of estuaries and coastal environments. To quantify suspended sediment, optical and acoustic backscatter instruments are often used. Optical backscatter systems are more sensitive to mud particles (<63 μm) and flocs, whereas acoustic...

Water injection for dredging sediment in reservoirs – insights from preliminary experiments

Dynamic Response of the Fluid Mud to a Tropical Storm

Fluid mud (FM) is a unique sedimentary feature in high-turbidity estuaries, where it can make a rapid contribution to morphodynamics. Insufficient field measurements and fixed-point monitoring lead to deficient understandings of the formation, transport, and breakdown of the FM under extreme weather conditions. A field survey was conducted in...

Sediment dynamics and transport regimes in a narrow microtidal estuary

Estuarine sediment dynamics are a consequence of various forcings (barotropic, estuarine circulation, and fluvial) that vary in space and time. Here, we present a study examining sediment dynamics in a narrow microtidal estuary, the Lower Passaic River in New Jersey, USA. The analysis incorporates measurements of suspended sediments,...

Limited seed retention during winter inhibits vegetation establishment in spring, affecting lateral marsh expansion capacity

Coastal systems worldwide deliver vital ecosystem services, such as biodiversity, carbon sequestration, and coastal protection. Effectivity of these ecosystem services increases when vegetation is present. Understanding the mechanisms behind vegetation establishment in bio-geomorphic systems is necessary to understand their ability to recover...

Sediment dynamics in Lagos Harbour reconnaissance on effects of dredging

Due to economic growth, Lagos Harbour is expanding. Capital dredging is needed to allow larger vessels to call the port. As harbour siltation is already a problem, increase of maintenance dredging is a worry. In the past no data was available to understand the hydraulics and sediment transport to estimate maintenance dredging volumes. This paper...

The effect of tidal asymmetry and temporal settling lag on sediment trapping in tidal estuaries

Over decades and centuries, the mean depth of estuaries changes due to sea-level rise, land subsidence, infilling, and dredging projects. These processes produce changes in relative roughness (friction) and mixing, resulting in fundamental changes in the characteristics of the horizontal (velocity) and vertical tides (sea surface elevation) and...

Tidal flat nematode responses to hypoxia and subsequent macrofauna-mediated alterations of sediment properties

To assess the role of macrofauna-mediated sediment changes on nematode community recovery, we examined the temporal development of macrobenthos, nematode communities and sediment properties following hypoxia in 16 m2 replicated plots over a 6 mo period. Hypoxia drastically changed nematode community composition (i.e. reduced diversity and...