VA剖面碳酸钙含量数据集（25000年以来）
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VA剖面的碳酸钙含量在整个剖面变化不大，只在剖面顶部出现了较大的波动，碳酸盐含量介于10%-20%之间。剖面记录了~25000 14C yr BP以来的气候变化。1）~25000-~22000 14C yr BP：总体上讲，这段时间内气候相对湿润，所有指标特别是粒度组分在这段时间内波动剧烈，反映了气候的不稳定性以及混合搬运(即风和水的混合)的影响。2）~22000-~19000 14C yr BP：碳酸钙含量变化微弱，极大的沉积速率反映了末次冰盛期气候寒冷且风力强盛，但是微弱的潜育化现象说明该时段气候仍然比较湿润。3）~19000-~10000 14C yr BP：这段时间内气候趋于稳定，碳酸钙含量等指标变化较小，粘土含量较高，反映了一定的成土作用，气候相对湿润。4）~10000-~5000 14C yr BP：这段时间为早全新世典型黄土沉积期，碳酸钙含量较下伏弱土壤层有所升高，相对于晚全新世，早全新世气候干旱。5）~5000 14C yr BP至今：碳酸盐含量曲线反映这段时间内发生了明显的淋溶作用，结合其它指标反映了晚全新世以来相对湿润的气候。
The calcium carbonate content of the VA profile varies minimally across the entire section, with notable fluctuations only occurring at the profile’s top, and the carbonate content ranges between 10% and 20%. This profile records climate changes since ~25000 14C yr BP. 1) ~25000–~22000 14C yr BP: Generally, the climate was relatively humid during this interval. All proxies, particularly grain size components, fluctuated sharply, reflecting climatic instability and the impact of mixed transportation (i.e., combined wind and water transport). 2) ~22000–~19000 14C yr BP: The calcium carbonate content changed only slightly. The extremely high sedimentation rate reflects the cold and wind-intense climate of the Last Glacial Maximum (LGM), while weak gleyization indicates that the climate remained relatively humid during this period. 3) ~19000–~10000 14C yr BP: The climate trended toward stability during this interval, with minimal changes in proxies including calcium carbonate content. The relatively high clay content reflects certain pedogenesis, and the climate was relatively humid. 4) ~10000–~5000 14C yr BP: This period constitutes the typical loess deposition stage of the Early Holocene. The calcium carbonate content increased compared to the underlying weak soil layer, and the Early Holocene climate was arid relative to the Late Holocene. 5) ~5000 14C yr BP to present: The carbonate content curve reveals that significant eluviation occurred during this period, which, combined with other proxies, indicates a relatively humid climate since the Late Holocene.
