摘要
The 1.06 m lacustrine core,which was from the proglacial Da Qiangyong Lake,southern Tibetan Plateau,was investigated;multi-indicators including grain size,magnetic susceptibility,element content,carbonate content and total organic carbon content in the sediment sample were analyzed.Based on the understanding of sediment source,the factors on these indicators and their significance on climate and environment were discussed.Associated with the radioisotope dating result,the above indicators were comprehensively compared,and the glacier and climate changes over the past millennium from Qiangyong Lake,southern Tibetan Plateau,were reconstructed.The results showed that the time scale of the 1.06 m sediment sequence was about one millennium since the 11th century;the sediment was mainly composed of dust particles which were carried by meltwater of Qiangyong glacier,and the variations of grain size,magnetic susceptibility and chemical contents of the sediment were closely related to the melting strength of Qiangyong glacier influenced by the regional climate change;the environmental temperature in southern Tibetan Plateau gradually increased with little fluctuation since the 11th century,and then Qiangyong glacier gradually melted.Particularly,the environmental temperature was lower and Qiangyong glacier weakly melted in southern Tibetan Plateau at the beginning of the 11th century;the climate was warm and the glacier strongly melted from the middle of the 11th century to the beginning of the 13th century;the Little Ice Age occurred and the melting of glacier greatly weakened from the beginning of the 14th century to the middle of the 18th century;the environmental temperature increased rapidly and the melting of glacier greatly strengthened since the middle-late of the 18th century.