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通过对腾格里沙漠南缘红水河剖面的地层分析和年代序列建立 ,依据分辨率 4 0～ 50a的TOC、TIC、元素和稳定同位素 (δ18O)分析及孢粉分析 ,重建了腾格里沙漠南缘过渡区全新世 80 0 0～ 30 0 0aBP期间的古气候演变序列 .结果显示 ,(7980 )～ 6 870aBP气候变化特点为具振荡性的升温期 ,且尤以 74 10～ 6 870aBP最为明显 ;6 870～ 4 6 2 0aBP为高温期 ,并可分为 6 6 2 0～ 5770aBP温暖而湿润的第 1高温期和 536 0～ 5130aBP以干热为特征的第 2高温期 .在 5880～ 536 0aBP ,即两个高温期之间 ,气候曾发生持续干化 ,温度有 3次波动降低 .第 1高温期可被视为本区全新世气候适宜期 . 5130～ 4 6 2 0aBP温度有所降低 ,但湿度增加 ,并在 4 830～ 4 790aBP存在一强降温事件 ,预示着全新世高温期的衰减 ;4 6 2 0aBP开始为降温期并在4 6 2 0～ 4 32 0 ,4 0 10～ 3590和 32 70～ (3110 )aBP出现 3次分别与高山冰进相关的低温期
Based on the stratigraphic analysis and chronological establishment of the Hongshuihe section on the southern margin of the Tengger Desert, Tenggerri was reconstructed based on TOC, TIC, δ18O analysis and sporopollen analysis with a resolution of 40 ~ 50 years. The paleoclimate evolution sequence during the Holocene 80 0 0 ~ 30 0 0 aBP in the transitional zone of the southern margin of the desert shows that the climate change characteristics of (7980) ~ 6 870aBP are oscillating warming periods, Obviously, 6 870 ~ 4 6 2 0 0 aBP is a high-temperature period and can be divided into a warm and wet first high temperature period of 6 6 2 0 ~ 5770 aBP and a second high-temperature period of 536 0 ~ 5130 a BP characterized by dry heat at 5880 ~ 536 0aBP, that is, between the two high temperature periods, the climate has been continuously desiccated and the temperature fluctuates for three times, and the first high temperature period can be regarded as the Holocene climatic suitable period in this area. But decreased with the increase of humidity, and there was a strong cooling event from 4 830 to 4 790 aBP, indicating the decay of the Holocene in the high temperature period; 4 6 2 0 a BP started to cool down and was in the range of 4620 ~ 4220, 4010 ~ 3590 and 32 70 ~ (3110) aBP appeared three times, respectively, associated with the alpine ice into the low temperature