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With the support of 18 AMS-14C data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 44.2 to 11 ka B.P. in the Jingning area. Over the period of 44―29 ka B.P. (MIS3), coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 23 ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3, further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.
With the support of 18 AMS-14C data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 44.2 to 11 ka BP in the Jingning area. Over the period of 44-29 ka BP (MIS3), coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 23 ka BP, the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3, further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.