The Behaviour of Dissolved Barium in Estuaries

Estuarine profiles of dissolved barium are reported from six estuarine systems in the U.S.A. and Europe. All show clear evidence of mid-estuarine barium concentration maxima, although the location and scale of these maxima vary. These differences are rationalized in terms of low-salinity desorption of particulate barium, estuarine particle dynamics, riverine sediment supply and barium storage and subsequent slow release in salt marshes. Low-salinity removal of barium also occurs in some estuaries, apparently related to dissolved iron and manganese removal.