Silver in the western equatorial and South Atlantic Ocean

Vertical profiles of total dissolved (<0.22 mum) silver concentrations in t he equatorial and southwest Atlantic Ocean provide a new perspective on the processes controlling the element's external fluxes and internal biogeoche mical cycling in the World Ocean. Atmospheric inputs of natural and/or indu strial aerosols appear to elevate silver concentrations in remote surface w aters in the South Atlantic, where silver is effectively scavenged onto and /or bioaccumulated by plankton. The subsequent remobilization of silver wit h depth is relatively coincident with that of silicate, suggesting much of that silver is sequestered within a refractory organic phase associated wit h biogenic silica. That silver is then remineralized, and appears to be con servatively transported in subsurface water masses throughout the World Oce an. (C) 2001 Elsevier Science Ltd. All rights reserved.