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通过对新疆巴里坤湖的地层剖面进行的精确定年和孢粉分析,结合现代表土孢粉数据,重建了该地区16.7cal ka BP以来的植被和环境演化历史.结果表明,在末次冰消期及早全新世(16.7～7.9cal ka BP)研究区以荒漠植被为主,A/C值所指示的有效湿度明显偏低,气候干旱.其中在16.7～8.9cal ka BP期间,气候环境最为恶劣;8.9～7.9cal ka BP为气候环境逐渐改善的过渡期.研究区在中全新世(7.9～4.3cal ka BP)为荒漠草原/草原,有效湿度明显升高,气候环境相对最为适宜,湖泊周围高地可能有片状的桦木林地出现.在4.3～3.8cal ka BP这一短暂时期,研究区植被由荒漠草原/草原迅速转变为荒漠,有效湿度显著降低,可能是一次百年尺度的干旱气候事件.研究区在晚全新世(3.8～0.53cal ka BP)呈现出典型的荒漠草原/草原草甸景观,有效湿度相对较高,气候环境相对较为适宜;0.53cal ka BP以来,呈现荒漠植被景观.区域对比显示,该地区16.7cal ka BP以来的气候环境演化特征与东亚季风影响区有着明显的差异,在末次冰消期-早全新世气候干旱,中全新世-晚全新世气候相对湿润.
Based on the accurate dating and sporopollen analysis of the stratigraphic section of Barkol Lake in Xinjiang and the combination of modern epiphytic sporopollen data, the history of vegetation and environment evolution since 16.7 ka ka BP has been reconstructed in this region. The Holocene (16.7 ~ 7.9cal ka BP) was dominated by desert vegetation, the effective humidity indicated by the A / C value was significantly lower and the climate was arid, of which the climatic environment was the worst during the period of 16.7-9.9 ka ka BP, and 8.9 ~ 7.9cal ka BP is the transitional period of gradual improvement of climate environment.The study area is in the desert steppe / steppe in the middle Holocene (7.9 ~ 4.3cal ka BP), the effective humidity is obviously increased, the climate environment is the most suitable and the high ground around the lake may be In the ephemeral period of 4.3 ~ 3.8 ka ka BP, the vegetation in the study area rapidly changed from desert steppe / steppe to desert, and the effective humidity decreased significantly, which may be a hundred-year-scale arid climate event. In the late Holocene (3.8-0.53cal ka BP), typical desert steppe / steppe meadow landscape is presented with relatively high effective humidity and relatively suitable climatic environment, and desert vegetation landscape since 0.53cal ka BP. The regional comparison shows that the climatic and environmental evolution characteristics of the region since 16.7 ka ka BP are obviously different from those of the East Asian monsoon. During the last ice extinction-Early Holocene climatic aridity, the Mid-Holocene-late Holocene climate is relatively humid.