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We develop a numerical model that encompasses wave induced current as well as advective and diffusion models to examine the effects of Stokes drift on pollutant transport within the surf zone on a plane beach. We also carried out dye diffusion experiments in the surf zone, and modelled wave-induced currents by applying the concept of radiation stress. We based wave propagation on the equation of wave energy conservation, while the advective diffusion model, including Stokes drift, was used to describe pollutant transport in the surf zone. We then used the alternative direction implicit finite difference method to differentiate between models, and evaluated the validity of these numerical approaches using a Gaussian pulse with a known exact solution. The numerical results of this study are in close agreement with analytical solutions. Finally, we applied our model to simulate pollutant transport within the surf zone on a plane beach. Results show that numerical modeling including Stokes drift more closely agrees with experiments than do results that exclude this drift. Thus, in general, we show that a pollutant will be more obviously transported shoreward in addition to the extent of expected drift. We therefore suggest that Stokes drift plays an important role inpollutant drift within thesurf zone, especially in ashoreward direction. [ABSTRACT FROM AUTHOR]

Consolidated silt is a special depositional landform. The properties,formation and evolution of consolidated silt,which relate to the fields of marine sediment dynamics and marine engineering geology,are of crucial importance for shore protection,navigation safety,and marine construction. This paper introduces the concept,characteristics and distribution of consolidated silt and focuses on mechanisms of formation and evolution. Recent research progress on consolidated silt is reviewed according to the three modes formation and evolution (i.e. primary deposition mode,coarsening and sorting mode,and liquefaction and seepage mode). New research ideas and methods with regards to consolidated silt are considered after analyzing the advantages and disadvantages of emphasizing the three modes. It is proposed that future research directions should:combine basic approaches of marine soil mechanics and sediment dynamics;carry out simultaneous observations of multiple-factors characterizing the water,seabed surface,and internal seabed;build an integrated conceptual model to describe the physical process;establish corresponding mathematical models to evaluate the formation and evolution of consolidated silt. [ABSTRACT FROM AUTHOR]