中国西北地区中晚全新世火历史集成重建与气候演化

为了探讨西北地区古火演化及其驱动机制，基于28个样点的炭屑和黑碳记录，集成重建该区8 kaBP的古火变化序列；同时结合古植被、古气候、历史文献等记录，分析了古火活动与气候变化和人类活动之间的关系。结果表明：西北地区中晚全新世火历史可以划分为4个阶段；① 火活动波动阶段（8～6 kaBP），古火事件发生频繁，主要受气候变化的影响；② 火活动平稳阶段（6～4 kaBP），气候趋于暖湿化，植被有所发展，贮藏了一定的燃烧质；③ 火活动快速上升阶段（4～2 kaBP），人类活动成为火事件的主要影响因素，古火活动频率呈现不断上升的趋势；④ 火活动大范围发生阶段（2～0 kaBP），气候由湿冷向干冷转化，生物质干燥易燃，农业快速发展，朝代更替和战争频繁，火活动异常剧烈。

Integrated reconstruction of fire history and climatic changes in Northwest China since mid-late Holocene

A total of 28 records of charcoal and black carbon were used to reconstruct the evolution and driving mechanism of paleofire events in Northwest China in the past 8 ka. Combined with paleovegetation, paleoclimate, and historical records, relationship among paleofire activity, climate change, and human impact was analyzed. Results show that during the middle and late Holocene, fire history in Northwest China can be divided into four stages: (1) the fluctuation stage of fire activity (8～6 kaBP), paleofire events occurred frequently and were mainly affected by climate change; (2) the stable stage of fire activity (6～4 kaBP), when the climate tended to be warm and humid, vegetation developed and stored a certain amount of combustible material; (3) the rapid rise stage of fire activity (4～2 kaBP), human activities became the main influencing factor for fire events, and the frequency of fire activities showed a rising trend; (4) the stage of large-scale fire activity (2～0 kaBP), the climate changed from wet-cold to dry-cold, biomass was dry and flammable, agriculture developed rapidly, dynasty changed and frequent wars occurred, and the fire activity was exceptionally intense.