A high resolution record of vegetation and environmental variation through the last ∼ 25,000 years in the western part of the Chinese Loess Plateau

Abstract

We present a high-resolution reconstruction of vegetation and environmental changes from a 40-m thick section in the western part of the Chinese Loess Plateau in attempt to reveal the details of the MIS 2 and MIS 1 climate variations. Our data show that a desert steppe occupied the landscape between ∼ 24,500 and ∼ 13,600 14C yr BP. Two episodes of further vegetation deteriorations occurred between ∼ 20,000 and ∼ 17,100 14C yr BP and between ∼ 15,100 and ∼ 13,600 14C yr BP, corresponding to the Heinrich events 2 and 1. The late glacial stage between ∼ 13,600 and ∼ 9880 14C yr BP included four sub-stages that correspond chronologically and climatologically to the European deglacial sub-stages. The first sub-stage (∼ 13,600 to ∼ 12,400 14C yr BP) corresponds to the Bølling warm period; the second sub-stage (∼ 12,400 to ∼ 11,500 14C yr BP) to the Older Dryas cold period; the third sub-stage (∼ 11,500 to ∼ 10,700 14C yr BP) to the Allerød warm period; and the fourth Sub-stage (∼ 10,700 to ∼ 9880 14C yr BP) to the Younger Dryas cold period. The early–mid Holocene (∼ 9880 to ∼ 4370 14C yr BP) was a period when a forest steppe dominated the landscape under a warm and wet climate. During this period, eight cool and dry spells occurred at ∼ 9720 14C yr BP (E1), ∼ 9380 14C yr BP (E2), ∼ 8870 14C yr BP (E3), ∼ 8660 14C yr BP (E4), ∼ 8440 14C yr BP (E5), ∼ 8240 to ∼ 8060 14C yr BP (E6), ∼ 7120 to ∼ 6550 14C yr BP (E7), and ∼ 5640 to ∼ 5120 14C yr BP (E8). After a major deterioration in vegetation between ∼ 4370 to ∼ 3270 14C yr BP, the study area experienced improved moisture conditions between ∼ 3270 to ∼ 1450 14C yr BP, followed by a persistent deterioration of vegetation under a drying climate during the past ∼ 1500 years.