| Abstract: | Systematic palynological research was conducted on more than 343 samples from a column or rock core obtained by drilling to a depth of 20 m in Gucheng lake. According to three assemblage zones and nine subzones of the sporo-pollen, and the dating of 14℃, we have explored the regularity of palaeoclimatic changes and palaeomonsoon activities since 15.0 ka BP. During 15.0 ～ 11.0 ka BP, the temperature had increased a little, but the climate was still cool and relatively dry, reflecting a weak wet monsoon and low precipitation at that time. In the period of 3～11.0 ka BP, it became cold and wet, with an increased effect of the dry monsoon, and the area was probably situated in a position of the frontal zone. Causing considerable effective humidity. Later than 11.0 ka BP, the temperature increased rapidly within 500 years with a subsquent, turn of the climate towards significantly warmer and wet and a further intensification of the monsoon effect. This rapid temperature increase corre-sponded to the increasing radiation of solar energy during 11.0～10.0 ka BP. From 10.5 to 6.4 ka BP, the wet monsoon was the priority climate of the region, albeit there were at least two or three spells of cooling, as well as decreasing of monsoon precipitation. |
