Hydrochemistry of water samples from CTD and towfish during METEOR cruise M147

The main component of this data base comprises elemental concentrations associated with dissolved organic matter obtained from samples collected on Meteor cruise M147 (May 2018). The data supports the manuscript Trace metal stoichiometry of dissolved organic matter in the Amazon Estuary. Dissolved organic matter (DOM) comprises a distinct component of the Earth's hydrosphere and provides a link between the biogeochemical cycles of carbon, nutrients, and trace metals (TMs). Binding of TMs to DOM is thought to result in a TM pool with DOM-like biogeochemistry. In this manuscript, we determined elemental stoichiometries of aluminium, iron, copper, nickel, zinc, cobalt and manganese associated with a fraction of the DOM pool isolated by solid phase extraction at ambient pH (DOMSPE-amb) from the Amazon estuary. We found the rank order of TM stoichiometry within the DOMSPE-amb fraction was underpinned by the chemical periodicity of the TM. Furthermore, the biogeochemistry of the TMSPE-amb pool was related to the chemical hardness of the TM ion. Thus, the biogeochemistry of TMs bound to the DOMSPE-amb component in the Amazon estuary was determined by the chemical nature of the TM and not by that of the DOMSPE-amb.