Release kinetics of Water Soluble Organic Carbon (WSOC) from river sediment and wetland soil

Release kinetics of Water Soluble Organic Carbon (WSOC) from a wetland soil and a river bottom sediment were investigated under various experimental conditions in the laboratory. The laminar sublayer concept was applied to model the release process. The results indicate that the release process can be characterized by a typical first order equation derived from the laminar sublayer modeling. The mass transfer rate constants of the release process increased with the increase in flow velocity following a power function. Due to texture difference, the transfer rate constant of the wetland soil is about one order of magnitude larger than that of the river bottom sediment. The influences of temperature and pH on the release kinetics are discussed.