Great changes occurred in the earth's surrounding environments during the Permian-Triassic (P-Tr) transition and resulted in the collapse of land and marine ecosystems. Thus

the most severe mass extinction in the earth's history appeared across the P-Tr boundary. Wildfire

as a key ecosystem driver and climate change indicator

is seldom reported in the documents of the pre-Quaternary researches. In this study

a 521 ka record of wildfire during the P-Tr mass extinction was recurred through the black carbon (BC) and combustion-derived polycyclic aromatic hydrocarbons (PAHs) records in the GSSP section of Meishan. There were frequent wildfires in the 163 ka of history just before the P-Tr mass extinction and the most intensive one occurred in the mass extinction event beds. No combustion records were found in the beds above mass extinction line and a wildfire gap (lasting 358 ka) was recognized in the Early Triassic. Wildfire gap may be not a local phenomenon

but a response of global climatic and environmental changes. Wildfire would vanish accompanied by the destruction of land vegetation and abrupt drop of atmospheric oxygen. Therefore

Meishan P-Tr wildfire gap can be used as an indicator of the mass extinction.