Shifting drivers of holocene fire regimes in Uzbekistan: From natural factors to anthropogenic impact

Abstract

In the context of the current fire intensification associated to climate aridification, this study explores Holocene fire regimes in the foothills of the Pamir-Alai Range (Uzbekistan) through macro-charcoal analysis of sediment cores from Lake Fazilman and the Ogshagil wetland, spanning the past 11000 years. In addition to their novelty, the results reveal distinct fire phases driven by both climatic fluctuations and human activities. During the early Holocene (12000–5000 cal. yr BP), fire activity was primarily climate-driven, with higher frequencies during arid phases. A significant shift occurred around 4000 – 3000 cal. yr BP, with synchronous fire trends at both sites suggesting increased anthropogenic influence linked to agro-pastoral practices of the Oxus Civilization, the Andronovo Cultures and the Handmade Painted Ware Cultures. Fire frequency declined during periods of intensified agricultural practices but increased again in later centuries, likely influenced by shifts in land use and socio-economic dynamics. Over the past 500 years, a rise in fire activity and woody plant combustion, likely influenced by post-medieval pastoral land use and firewood transportation, suggests intensified human impact. This study provides new insights into the interplay between climate, vegetation, human activity and fire in shaping Central Asia's steppe landscapes.