Fate modeling of mercury species and fluxes estimation in an urban river

The fate and transfer of mercury in urban river is an important environmental concern. In this study, QWASI (Quantitative Water-Air-Sediment Interaction) model was selected to estimate the levels of total mercury and three mercury species in water and sediment, and was used to quantify the fluxes of mercury at water/air and sediment/water interfaces of an urban river. The predicted mercury levels in water and sediments were closed to the measured values. Water inflow, re-suspension of sediment and diffusion from sediment to water are major input sources of mercury in water. The net mercury transfer flux from water to air was 0.16 ng/(m2 h). At the sediment/water interface, a net total mercury transfer of 1.32 ng/(m2 h) from water to sediment was seen. In addition to the existing dynamic flux chambers measurement, this model method could provide a new perspective to identify the distribution and transfer of mercury in the urban river.