Holocene fire history in China: Responses to climate change and human activities.

Fire is an intrinsic feature of terrestrial ecosystems as well as a key Earth system process that significantly influences ecosystem patterns, the carbon cycle, and climate. Although local and regional paleofires across China have been investigated, the history of these phenomena at the national scale as well as possible drivers remain unknown. This study investigated spatiotemporal patterns in fire activity across China based on 107 individual site charcoal records. The aim of this work was to discuss the possible impact of climate and human activities on fire in China. Results showed that fire activities across China declined gradually overall between the early Holocene (12 ka BP) and the middle Holocene (7.3 ka BP) but then sharply increased in occurrence after 7.3 ka BP. Data showed that although regional fire activities did not vary synchronously, more events tended to occur in the late Holocene and there were relative less in the early-to-middle Holocene. These changes in Holocene fire activity closely mirrored millennial scale moisture variations across China. Intensified human activities over the last 3 ka might also be responsible for a sharp increase in fire activity. Variable trends in fire activities within regions might also be attributed to large-scale climatic controls modulated by local factors, which determined burn likelihood. This study enhances our insights into the fire history of China and may help to provide improved future projections for such phenomena given current climate change.