High-resolution pollen sequence from Lop Nur, Xinjiang, China: Implications on environmental changes during the late Pleistocene to the early Holocene

Abstract

A 9.35-m long sediment core, CK2, that covers the time span between 31.98 and 9.14 kilo annum before present (ka BP) at the Luobei Depression (Lop Nur, Eastern Xinjiang, Northwest China) was studied by pollen analysis. The pollen assemblages of coniferous trees, temperate deciduous trees, herbs, and shrubs can be divided into the following four stages: Zone I (31.98ka BP to 19.26ka BP) corresponds to a steppe or desert steppe landscape, which conforms to the cold-wet climatic environment of the Last Glacial Maximum; Zone II (19.26ka BP to 13.67ka BP) corresponds to a steppe–desert or desert landscape, which conforms to the warm-arid climatic environment of the transient interglacial period; Zones III (13.67ka BP to 12.73ka BP) and IV (12.73ka BP to 9.14ka BP) are similar to Zones I and II, respectively, corresponding to the late last glacial and post last glacial, i.e., Early Holocene, respectively. The climatic environment in Lop Nur was increasingly getting drier based on Artemisia/Chenopodiaceae ratios of ≤0.5 in Subzones IVa and IVc. The Heinrich cold events (H3, H2, H1, and YD) and the Dansgaard–Oeschger warm events (IS4, IS3, IS2, IS1) with millennial-scale changes appearing at high latitudes can also be found in the pollen records of Lop Nur. Results show that the climate characteristics of the Lop Nur region are mainly controlled by the westerly belt, as displayed in mainly cold-wet or warm-arid synchronization. These climate characteristics differ from those of the monsoon area, which are mainly displayed in cold-arid and warm-wet synchronization but also restricted by the atmospheric circulation at high latitudes.