Isotopic evidence for complex biogeochemical cycling of Cd in the eastern tropical South Pacific

摘要

Over the past decades, observations have confirmed decreasing oxygen levels and shoaling of oxygen minimum zones (OMZs) in the tropical oceans. Such changes impact the biogeochemical cycling of micronutrients such as Cd, but the potential consequences are only poorly constrained. Here, we present seawater Cd concentrations and isotope compositions for 12 depth profiles at coastal, nearshore and offshore stations from 4 degrees S to 14 degrees S in the eastern tropical South Pacific, where one of the world's strongest OMZs prevails.