Variations in Holocene fire activity and its controls in the Ningshao Plain, eastern China

Extensive fires pose catastrophic threats to both human and natural ecosystems. Understanding the history of fire, particularly Holocene palaeofire activity in densely populated areas, is essential for predicting future fire risks and developing effective fire management policies. The complexity of fire activity is influenced by various factors, including climate and anthropogenic activities. In this study, we analysed microcharcoal from the top 35.36 m of a well-dated sediment core HMD1401 in Ningshao Plain, eastern China. We combined our findings with phytolith and diatom evidence to obtain a comprehensive understanding of variations in Holocene fire activity and its controls. The results showed that there was higher fire activity during the early and late Holocene and less fire activity during the mid-Holocene. More frequent fire occurred from c. 10 000-7000 cal. a BP and was primarily caused by abundant biomass and high seasonal flammability due to increased annual temperature and precipitation and warm but dry winter climate. Fire occurrences between c. 7000-2000 cal. a BP remained at a low level, except for the periods c. 5900-5600 cal. a BP and c. 5300 cal. a BP, which may have been caused by extreme climate events. The impact of fire caused by human activity was significantly enhanced during the last two millennia.

Automated summary

By analysing sediment cores from Ningshao Plain in eastern China, this study examined the variations in Holocene fire activity. The results showed higher fire activity during the early and late Holocene and a decrease during the mid-Holocene. Factors such as climate and human activities influenced fire occurrences, with human-caused fires becoming more significant in the last two millennia.