Pathway and distribution of trace elements in Lake Vanda, Antarctica

Abstract

Lake Vanda, an Antarctic saline lake, situated in the Dry Valleys area, Victoria Land, has a unique distribution of temperature, chlorinity and nutrient matters. Although the origins of these properties and major elements have been discussed previously1–6, only a few geochemical studies have been undertaken on trace elements7,8. We report here concentrations of 14 trace elements, including 7 elements not previously measured (Sc, Cr, Co, Rb, Sb, Cs and Th), in the lake that were determined by instrumental neutron activation and atomic absorption methods. The concentration of every element except for aluminium increased abruptly in the highly stratified deep layer. The chemical composition of inflow water was the same as those of tropospheric aerosol particles9,10 and snow11,12 at Antarctica. We suggest that the pathway of the trace elements observed in Lake Vanda was: tropospheric aerosol particles→precipitation→glacier→glacial melt water→Lake Vanda. The composition of these elements in the highly stratified layer has been secondary transformed by the reduction, removal and ion-exchange processes.