Trace metal stoichiometry of dissolved organic matter in the Amazon plume.
Martha GledhillAdrienne HollisterMichael SeidelKechen ZhuEric Pieter AchterbergThorsten DittmarAndrea KoschinskyPublished in: Science advances (2022)
Dissolved organic matter (DOM) is a distinct component of 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. Here, we determined elemental stoichiometries of aluminum, iron, copper, nickel, zinc, cobalt, and manganese associated with a fraction of the DOM pool isolated by solid-phase extraction at ambient pH (DOM SPE-amb ) from the Amazon plume. We found that the rank order of TM stoichiometry within the DOM SPE-amb fraction was underpinned by the chemical periodicity of the TM. Furthermore, the removal of the TM SPE-amb pool at low salinity was related to the chemical hardness of the TM ion. Thus, the biogeochemistry of TMs bound to the DOM SPE-amb component in the Amazon plume was determined by the chemical nature of the TM and not by that of the DOM SPE-amb .
Keyphrases
- solid phase extraction
- organic matter
- ms ms
- liquid chromatography tandem mass spectrometry
- high performance liquid chromatography
- molecularly imprinted
- tandem mass spectrometry
- oxide nanoparticles
- simultaneous determination
- transcranial magnetic stimulation
- gas chromatography mass spectrometry
- heavy metals
- liquid chromatography
- ultra high performance liquid chromatography
- reduced graphene oxide
- microbial community
- high frequency
- mass spectrometry
- human health
- health risk assessment