High-resolution analyses of annually laminated sediments of Lake Shira to reconstruct Holocene environmental variability and its relation to natural climate drivers and human occupation in northern Inner Asia

45，000年来，北方内亚一直是一个重要的十字路口地区，见证了人类移民潮，促进了文化和技术交流。从5,000年前开始，它见证了早期农牧社会从欧亚大陆东部和西部的传播，他们的混合和转变，以及土著人民逐渐和有选择地采用驯养的动物和植物。在青铜器时代，该地区成为主要技术创新和强大游牧帝国的摇篮，有力地塑造了整个欧亚大陆的文化和政治发展。然而，人们对早期农牧经济对自然环境的影响以及气候变化对文化发展的影响知之甚少。由于人为的全球变暖，该区域被认为是高度脆弱的，例如，温度上升和蒸发可能影响植被组成，增加野火和沙尘暴的可能性。然而，仍然缺乏北方内亚洲的高质量代用记录，这些记录可以更好地了解气候对区域环境的影响，并对人类与环境的相互作用提供新的见解。阿尔泰-萨彦地区希拉湖的纹状沉积物被认为是过去8,000年来气候和环境变化的宝贵档案。拟议项目旨在分析2021年3月从湖泊中回收的一组新的沉积物岩心，以（1）通过显微镜纹孔计数和放射性碳测年为沉积序列建立可靠的年代学，（2）通过高分辨率花粉和微木炭分析获得区域植被，火灾和气候历史的详细重建，（3）通过分析水生非花粉孢粉组合和沉积物性质，重建水文气候和湖沼变化。第四个目标是综合来自亚洲内陆北方的考古遗址和放射性碳数据，以重建全新世中期和晚期人口动态和生计变化的时空模式。拟议项目的结果将填补我们在过去8,000年中对研究区域的气候和环境变化、人类住区动态、殖民和适应的知识空白，因此对于理解横贯大陆的过程至关重要。

For 45,000 years, northern Inner Asia has been an important crossroads region that witnessed waves of human migrations and facilitated cultural and technological exchange. Beginning 5,000 years ago, it saw the spread of early agropastoral societies from East and West Eurasia, their mingling and transformation, and the gradual and selective adoption of domesticated animals and plants by indigenous peoples. In the Bronze Age, the region became a cradle of major technological innovations and powerful nomadic empires that strongly shaped cultural and political developments throughout Eurasia. However, little is known about the impact of early agropastoral economies on natural environments and the effect of climate change on cultural developments. Due to anthropogenic global warming, the region is considered to be highly vulnerable, as rising temperature and evaporation, for example, could affect vegetation composition and increase the likelihood of wildfires and sandstorms. However, there is still a lack of high-quality proxy records from northern Inner Asia that could provide a better understanding of climatic impacts on the regional environment as well as new insights into human-environment interactions. The varved sediments of Lake Shira in the Altai-Sayan region have been recognised as a valuable archive of climatic and environmental variability over the last 8,000 years. The proposed project aims to analyse a new set of sediment cores recovered from the lake in March 2021 to (1) establish a robust chronology for the sedimentary sequence through microscopic varve counting and radiocarbon dating, (2) obtain a detailed reconstruction of the regional vegetation, fire and climate histories through high-resolution pollen and microcharcoal analyses, and (3) reconstruct hydroclimatic and limnological changes through analyses of aquatic non-pollen palynomorphs and sediment properties. A fourth goal is the synthesis of archaeological site and radiocarbon data from northern Inner Asia to reconstruct spatial and temporal patterns of population dynamics and subsistence changes during the Middle and Late Holocene. The results of the proposed project will fill gaps in our knowledge of climate and environmental changes, human settlement dynamics, colonization, and adaptations in the study region during the last 8,000 years, and are therefore essential for understanding transcontinental processes.