Senescence as the main driver of iodide release from a diverse range of marine phytoplankton

The reaction of ozone with iodide at the sea surface is now assumed to contribute up to 70 % to tropospheric iodine, which is of great significance for several tropospheric chemical cycles. The presented study is one of the most comprehensive investigations into biologically mediated iodate-to-iodide conversion, investigating 10 phytoplankton species from several different climatic zones and algal groups. We found no relation to certain algal groups, or to their origin. However, we could confirm that the senescence stage of the algal cultures at the end of the experiment is an important driver for iodate-to-iodide conversion rates. Understanding the time lag between iodate incorporation and iodide production is one of the key factors to understanding global surface iodide production, and hence its’ impact on the marine troposphere.

Reference: Hepach, H., et al. (2020). Senescence as the main driver of iodide release from a diverse range of marine phytoplankton, Biogeosciences, 17, 2453–2471, https://doi.org/10.5194/bg-17-2453-2020.

Read and download the publication here: https://www.biogeosciences-discuss.net/bg-2019-443/bg-2019-443.pdf