Heavy metal distribution model under estuarine mixing

✍ Scribed by F. Mwanuzi; F. De Smedt

• Book ID: 101283317
• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 229 KB
• Volume: 13
• Category: Article
• ISSN: 0885-6087
• DOI: 10.1002/(sici)1099-1085(19990415)13:5<789::aid-hyp781>3.0.co;2-f

✦ Synopsis

In modelling the fate and transport of heavy metals, the sorption processes, through the distribution coecient, are applied to determine the amount of sorbed and dissolved fractions. Usually, these distribution coecients are assumed to depend only on suspended sediment interactions. In estuaries, however, observations indicate that dissolved concentrations increase with salinity. It is hypothesized that salt competes for binding sites, leading to lower distribution coecients. To study the fate and transport of heavy metals in an estuarine environment, a two-dimensional ®nite volume, depth-averaged toxic transport model has been developed. The distribution coecients are approximated as a function of sodium activity or salt concentration. Other model parameters are obtained from a recently developed hydrodynamic model, salt transport and cohesive sediment transport modules. The model has been applied to the Scheldt Estuary and the results for both sorbed and dissolved heavy metal concentrations agree fairly well with measured data, indicating that under estuarine mixing, salt concentration is an important factor aecting the fate and transport of heavy metals.