C, N and S analysed with a CNS elemental analyser (EuroEA, Eurovector). Biogenic silica was measured following the leaching method of Müller & Schneider (1993, doi:10.1016/0967-0637(93)90140-X). The sediment core HZM19 was collected in 2019, from Holzmaar, West-Eifel Volcanic Field in Germany using a UWITEC Piston Corer. The sediment core was collected to reconstruct environmental and climate changes of Holzmaar for the last 16,000 years cal BP. Particularly in this data set we cover between 2450-2950 cal BP.

Funding information: Georg Forster Research Fellowship for postdoctoral researchers (for the Alexander von Humboldt funding) Central Research Development Fund (CRDF) of the University of Bremen, 04 Independent Project for Postdocs– Funding objective B