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黄土是公认的三大古气候记录载体之一,全新世黄土由于位于顶层极易受到人类活动的影响,故研究程度不高。最近在甘肃会宁白草塬发现一个沉积连续、分辨率高、且保存完整的全新世黄土剖面,该剖面忠实地记录了全新世古气候演化,能够很好地与三宝洞和葫芦洞石笋氧同位素记录全新世古气候进行对比:二者共同记录了约12.5～11.5ka之间的Younger Dryas冷干事件;约10.5～5.2ka全新世适宜期,但是适宜期中气候变化具有不稳定性;5.2ka至今,气候较全新世适宜期慢慢变干变冷,二者相互印证了东亚季风区全新世古气候演化的一般过程;而驱动二者演化主要因素是太阳辐射量的变化。位于黄土高原西北边缘的会宁白草塬剖面中的磁化率和粒度两参数相比较:粒度较磁化率波动更频繁,记录古气候变化更灵敏。
Loess is recognized as one of the three major ancient climate record carriers. Holocene loess is not highly studied because it is highly susceptible to human activities at the top. Recently, a continuous, high-resolution and well-preserved section of the Holocene loess was discovered in Baicaoyuan, Huining, Gansu. This section faithfully recorded the Holocene paleoclimate evolution and is well correlated with the oxygen isotopes of stalagmites in the Sambo and Gourd Cave Record Holocene Paleoclimate for comparison: the two recorded together between about 12.5 ~ 11.5ka Younger Dryas cold-dry event; about 10.5 ~ 5.2ka Holocene suitable period, but suitable period of climate change instability; 5.2ka so far, The climate becomes drier and colder than the Holocene, which confirms the general process of Holocene paleoclimate evolution in the East Asian monsoon region. The main factor driving the evolution of the two is the change of solar radiation. The magnetic susceptibility and particle size of the Huining Ningbaicaoyuan profile located on the northwestern margin of the Loess Plateau are more sensitive to the changes of the magnetic susceptibility than the grain size.