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利用光释光测年技术,获得了覆盖科尔沁沙地内部及外围的20个风成沙-砂质古土壤沉积序列的年代。在分析前人研究的基础上,结合地层和气候代用指标重建了末次盛冰期以来科尔沁沙地的演化过程。结果表明:科尔沁沙地的气候变化和沙丘的固定与活化主要经历了4个阶段,即:26~12ka,气候极端干冷,沙地大面积活化;12.0~9.5ka,气候趋于暖湿,但仍比较干冷,沙地由大规模沙化向固定成壤过渡;9.5~2.5ka,气候暖湿,沙地基本固定;2.5ka以来,气候呈干冷与暖湿交替状态,沙地亦存在多次固定与活化,其中,从1.5ka开始,沙丘活化明显。基于风沙沉积序列的空间分布和光释光测年结果,末次盛冰期科尔沁沙地同时向南和北扩展:南至翁牛特-库伦旗一线,至少扩张了26km;北至霍林河一带,至少扩张了30km;东界受东辽河限制,与现代边界几乎一致。沙地面积较现代扩张了至少2.05×10~4km~2,扩大了37.7%。全新世大暖期,沙丘大面积固定。研究表明,科尔沁沙地气候与环境演变受东亚季风影响,也是全球气候变化的区域响应。
By using optical dating technique, the ages of 20 sedimentary sequences of aeolian sand-sandy paleosol in and around Horqin Sandy Land were obtained. Based on the analysis of previous studies, the evolution of Horqin Sandy Land was reconstructed with the stratigraphic and climatic proxy indicators. The results show that climate change and sand dune fixation and activation in Horqin Sandy Land have mainly experienced four stages, ie 26 ~ 12ka, the climate is extremely dry and cold, the sand area is activated in a large area, and the climate tends to be warm and humid in 12.0 ~ 9.5ka It is still relatively dry and cold, the sandy land is transformed from large-scale desertification to fixed-soil formation; 9.5 ~ 2.5ka, the climate is warm and wet and the sand is basically fixed; since 2.5ka, the climate is dry-cold and warm- And activation, which, from 1.5ka start, obvious dune activation. Based on the spatial distribution and photosoluminescence dating of aeolian sedimentary sequences, the Horqin sandy land expanded to the south and north at the same time during the last glaciation: at least 26 km wide from the Wenguite-Kulun Banner to the south; at least to the Huolinhe area in the north, at least Expansion of 30km; east by the East Liao River restrictions, almost the same with the modern border. The area of sandy land has expanded by at least 2.05 × 10 ~ 4km ~ 2 more than that of modern times, an increase of 37.7%. During the Holocene Holocene, dunes were fixed in large area. Studies have shown that the climate and environmental evolution in the Horqin Sandy Land are affected by the East Asian monsoon and also a regional response to global climate change.