Arsenic, antimony and vanadium in the North Atlantic Ocean

Abstract

New measurements of arsenic, antimony and vanadium in samples from vertical profiles at nine stations between 50° and 70°N in the Atlantic Ocean are presented. Antimonate concentrations exhibit little variation with depth and location, the average concentration being 1.16 nmol 1 -1. The vertical distribution of arsenate is similar to that reported for the South Atlantic and Pacific Ocean, with somewhat lower surface concentrations (14 to 18 nmol 1 -1) and uniform deep water concentrations (mean, 19 nmol 1 -1). Uniform vertical profiles for vanadium with a mean concentration of 32.6 nmol 1 -1 are in agreement with data for the Central Atlantic, but differ from profiles in the Pacific which exhibit surface water depletion. The presented data for As and V have extended the limited basis for comparison, so that inter-ocean fractionation processes can now be recognized. The concentrations of both As and V show regular increases in the ocean deep water as it passes from the North Atlantic (As 19.0; V 32.6 nmol 1 -1) via the South Atlantic (As 21.1 nmol 1 -1) and Indian Ocean (As 22.5; V 35.6 nmol 1 -1) to the Pacific Ocean (As 24.0; V 36.4 nmol 1 -1). The magnitude of biological recycling for V and As, as deduced from interoceanic fractionation, is consistent with estimates based on particle or algal compositions.