Articles | Volume 18, issue 15
Biogeosciences, 18, 4535–4548, 2021
Biogeosciences, 18, 4535–4548, 2021

Research article 04 Aug 2021

Research article | 04 Aug 2021

How are oxygen budgets influenced by dissolved iron and growth of oxygenic phototrophs in an iron-rich spring system? Initial results from the Espan Spring in Fürth, Germany

Inga Köhler et al.

Model code and software

Code PHREEQC D. L. Parkhurst and C. A. J. Appelo

Short summary
We investigated how high Fe(II) levels influence the O2 budget of a circum-neutral Fe(II)-rich spring and if a combined study of dissolved O (DO) and its isotopic composition can help assess this effect. We showed that dissolved Fe(II) can exert strong effects on the δ18ODO even though a constant supply of atmospheric O2 occurs. In the presence of photosynthesis, direct effects of Fe oxidation become masked. Critical Fe(II) concentrations indirectly control the DO by enhancing photosynthesis.
Final-revised paper