Comment on the Kaiho et al., paper “A forest fire and soil erosion event during the Late Devonian mass extinction” [Palaeogeography, Palaeoclimatology, Palaeoecology 392 (2013): 272-280]

Kaiho et al. (2013, Palaeogeography, Palaeoclimatology, Palaeoecology 392 (2013): 272-280) interpreted the occurrence of elevated concentrations of high molecular weight polycyclic aromatic hydrocarbons and dibenzofuran as indicators of wildfires and enhanced run-off near the Frasnian-Famennian (F-F) boundary. We argue that other processes, including weathering or hydrothermal oxidation (not discussed by Kaiho et al.) led to the observed increase in the concentration of these compounds and also changed their distribution. Kaiho et al.'s evidence for soil erosion and eutrophication-induced euxinia is also weak in the case of the investigated Belgian sections. Finally, Kaiho et al. rather unfortunately omitted a great wealth of important data published elsewhere, choosing instead to include only those which support their ideas and interpretations.