Holocene fire records and their drivers in the westerlies-dominated Central Asia

Abstract

Fire plays an important role in carbon emissions and climate changes in the Earth system and global/regional fires in the past have been detected. However, palaeofire history and their potential drivers are poorly understood in Central Asia. We in this study synthesized existing sedimentary charcoal records to reconstruct Holocene fire history in Central Asia and then assessed the relative importance of two potential controls (climatic and anthropogenic factors) on its trends. The results are: (1) Fire activity had insignificantly increased since ~7.9 cal. yr BP in Central Asia, although there was an obvious difference when fire history at different elevations is considered; (2) Periods of high fire activity occurred in the early-middle Holocene following by a decreasing trend in the late Holocene at high elevation, which might be attributed to a cooling temperature and the cooling-caused low biomass burning in the Holocene interval; (3) Episodes of high fire activity were common in the late Holocene and were primarily driven by the wetting-induced increased biomass burning, reinforced by the intensified human activities in middle-low elevation. Our findings could not only provide new unique insight about the long-time-scale fire-human-climate-vegetation interactions and also provide reasonable guidance for fire management given current climate change in Central Asia.