Changes in Climate, Environment, and Fire Activity along the Western Silk Road Over the Past 2000 Years

The Asian drylands is a critical component of the Silk Road, comprising primarily the arid central Asia (ACA) and the arid west Asia (AWA). This region is highly sensitive to global changes, and the spatial patterns of climate change and variations in fire activity are prominent scientific concerns. We reconstructed the history of vegetation succession and climate change in the Asian drylands over the past 2000 years, explored the spatial differences in climate change, and revealed the history of fire activity and its influencing factors: In ACA, both LakeSasikul and Lake Bazangan records exhibit climatic characteristics of the Medieval Warm Period (MWP) aridity and a wetter climate during the Little Ice Age (LIA). However, in AWA, Almalou peat and its surrounding areas show climatic characteristics of a wetter MWP and a drier climate during the LIA. (2) On the centennial scale, in ACA and AWA have a dipole pattern of precipitation variations, which is consistent with the intergenerational precipitation changes in the global warming, revealing that this may be the fundamental feature of climate change in the Asian drylands. (3) The evolution of fire activity in the western section of the Silk Road has been gradually increasing over the past 2000 years. In Lake Bazangan, fuel (biomass) conditions are the main limiting factor for the evolution of fire activity in the natural state; in Lake Sasikul, the natural changes in climate dryness/wetness are the main controlling factors affecting the fire activity; in Amalou peat, the fire activity is affected by the fuel (biomass) and climate, showing a more complex response model.