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The paleoclimate and paleoenvironment of Qinghai Lake indicated by a 16000-year pollen record are as follows. It was very cold and dry before 15200 years. During the Late Glacial, the climate varied from colder and semiarid to cool and semi-humid and fluctuated frequently but with little amplitude. Three cold events in the periods of 13400-13000, 11600-12000, and 11000-10400 aBP respectively correspond to the Oldest Dryas, Older Dryas and Younger Dryas events, whereas the two warm periods between them, 12000-13000 and 11600-11000 aBP, respectively correspond to Boiling and Allerod periods. The temperature increased abruptly after the Younger Dryas event, and then the climate gradually turned to be warm and wet from warm and semiarid. In the Holocene, the largest amplitude of cold event that occurred at ca. 8200 aBP is quite prominent. The Holocene climatic optimum culminated at 6700 aBP. After 2100 aBP, the climate tended to be cold and dry, keeping on up to now. Palaeoclimatic evolution and events of Q
The paleoclimate and paleoenvironment of Qinghai Lake indicated by a 16000-year pollen record are as follows. It was very cold and dry before 15200 years. During the Late Glacial, the climate varied from colder and semiarid to cool and semi-humid and fluctuated frequently but with little amplitude. Three cold events in the periods of 13400-13000, 11600-12000, and 11000-10400 aBP respectively correspond to the Oldest Dryas, Older Dryas and Younger Dryas events, while the two warm periods between them, 12000-13000 and 11600-11000 aBP, respectively correspond to Boiling and Allerod periods. The temperature increased abruptly after the Younger Dryas event, and then the climate gradually turned to be warm and wet from warm and semiarid. In the Holocene, the largest amplitude of cold event that occurred at ca. 8200 aBP is quite prominent. The Holocene climatic optimum culminated at 6700 aBP. After 2100 aBP, the climate tended to be cold and dry, keeping on up to now. Palaeoclimatic evoluti on and events of Q