The role of tidal processes on intertidal surface sediments is frequently stated but rarely investigated due to the methodological restrictions. This study provides a basis for describing the tidal effects on the mangrove sediment. It reports investigations into the chemical composition of mangrove surface sediment in Mengkabong lagoon, Sabah, Malaysia. The levels of 16 parameters were determin...

Sediment denitrification rates seem to be lower in tropical environments than in temperate environments. Using the isotope pairing technique, we measured actual denitrification rates in the sediment of tropical coastal lagoons. To explain the low denitrification rates observed at all study sites (<5 μmol N2 m-2 h-1), we also evaluated potential oxygen (O2) consumption, potential nitrification, ...

Microphytobenthos-macrofauna sediment interactions and their effects on sediment erodability were examined in laboratory experiments. Sediment beds were manipulated in a tidal mesocosm to produce diatom mats in exponential or in stationary phases of development after 6, 8 or 11 d of culture. These sediment beds were used in flume experiments to investigate the influence of bioturbation by the g...

The one-dimensional (vertical) sediment-transport model SEDTRANS96 has been upgraded to predict more accurately both cohesive and non-cohesive sediment transport. Sedtrans05 computes the bed shear stress for a given set of flow and seabed conditions using combined wave-current bottom boundary layer theory. Sediment transport (bedload and total load) is evaluated using one of five methods. The m...

A three-dimensional mixture theory model (SedMix3D) was used to simulate the flow and sediment transport over vortex ripples for scaled laboratory conditions. SedMix3D treats the fluid-sediment mixture as a continuum of varying density and viscosity with the concentration of sediment and velocity of the mixture calculated using a sediment flux equation coupled to the Navier-Stokes equations for...

Retention of particles in seagrass canopies is usually attributed to only the indirect, attenuating effects canopies have on flow, turbulence and wave action, promoting sedimentation and reducing resuspension within seagrass meadows. Yet recent evidence suggests that seagrasses are also able to affect particle flux directly through loss of momentum and increased path length derived from collisi...

The design and construction of a small wave-sediment tank, built and instrumented for under $10,000, is described. The tank is equipped with a piston-type wavemaker, capable of producing both small-amplitude and solitary waves. The middle section of the tank contains a sediment bed appropriate for wave-soil-structure interaction and sediment transport experiments. Wave energy is absorbed by a g...

Meiofauna and macrofauna communities and several sediment characteristics were compared between a slope situated far from the coast (Goban Spur) and two transects across the Iberian Margin with steep slopes and close to the shore. The northern Galician transect (off La Coruña) was situated in an area subjected to wind-induced upwelling events. The western Galician transect was also subjected to...