沙漠是地球表层系统的重要组成部分，研究沙丘系统对不同气候情景的响应是全球变化及其应对领域的前沿热点。呼伦贝尔沙地地处东亚夏季风边缘、环境脆弱敏感，在晚更新世以来经历了冷暖干湿多种变化，汇集了丰富的沙丘类型，且沙区内部小湖泊星罗棋布，是研究地表过程的理想场所。本项目拟统筹沙区内部的风沙沉积和湖泊沉积、沙区边缘的沙黄土和更老的冲洪积物地层，从地表过程角度入手，重建呼伦贝尔沙地地貌景观发育过程及其在不同气候背景下的环境格局。将沙区内部古环境记录和毗邻地区湖泊、泥炭、树轮等古气候重建结果及古气候数值模拟对比分析，剖析环境演变的驱动因素和沙丘建造/破坏机制。在大规模沙丘地层调查的基础上，探索晚全新世风沙堆积/侵蚀和人类活动之间的关联，评估东北呼伦贝尔地区“人类世”开始的时间和地表响应过程。本项目的实施，可促进理解全球变暖和人类活动增强背景下环境敏感脆弱地区景观发育过程，为未来沙漠化防治提供科学依据。

Deserts are an essential component of the Earth's surface system. Studying the response of dune systems to climate fluctuations in the past and present is a hot topic within the global change science community. The Hulunbuir sandy land is the northernmost eolian depositional system in China. The sandy land is sensitive to climatic variability due to its location at the northern limit of the East Asian summer monsoon system. It contains abundant dune types and well-developed drainage systems as shown by the widespread paleochannels and small lakes. This combination makes the Hulunbuir sandy land an ideal area to study the interactions between various surface processes in the semi-arid region and their behaviors under different climate scenarios. This project will focus on dune and lacustrine deposits collected from the dune fields, the sandy loess at the margins, and from the alluvial-fluvial deposits underneath. These sedimentary archives will be used to reconstruct the eolian landscapes evolutionary pathways and spatial patterns under past climate regimes. The stratigraphic evidence extracted from the dune fields will be compared with paleoclimatic records from the nearby lakes, peatlands, tree rings, and numerical simulations to identify the driving forces of regional environmental change and the mechanisms of dune building and destruction. This project will use multiple palaeoenvironmental records from the Hulunbuir sandy land to explore the relationship between eolian landscape collapse and human activities in the late Holocene and evaluate the start time and regional surface response to the “Anthropocene” in northeast China. Results from this project will help to understand the impact of past climate change and current anthropogenic global warming on landscape dynamics in environmentally sensitive regions and provide a scientific basis for desertification control in the future.