| This paper used a geochemical analysis of core sediments from a twenty-meter column taken from Lotus Mountain in Kunming, Yunnan, China to reconstruct environmental conditions over the past 20 kyr. ICP-MS operation condition was used in the determination of trace elements (Li, Rb, Cs, Be, Sr, Ba, Se, Ga, Th and U), heavy metals (Cr, Ni, Pb and Co), and REEs (La, Ce, Pr, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu). ICP-AES was used to determine Al, Ti, Ca, Mg, Fe and Mn. Na was determined by AAS. The age of the sediment column was determined by 14C analysis.The general trend for Na/Al, Mg/Al and Ca/Al ratios were similar as well as higher than they were 10 thousand years ago, which correlates with the gradually warming climate during the Holocene (dated from 11 thousand years ago).The Mg/Ca ratio was used as an indicator of temperature change. The results indicated that temperatures between 20-11kaBP gradually decreased before starting to warm from 11-2kaBP. The last 2,000 years have seen temperatures once again decreasing.The Rb/Sr ratio recorded similar a pattern with temperatures decreasing between 20～17kaBP, warming between 17～115kaBP, then becoming particularly warm between 11 to 5kaBP before cooling during the last 5,000 years.Chondrite patterns for the REEs were all similar. The meanδEu value was 0.72, which showed the core sediments to be part of the negative Eu anormally, while the meanδCe value was 7.12, which showed the core sediments as a positive Ce anormally. Values for the∑LREE/∑HREE ratio showed that the sediments were rich in LREE Futhermore, the individual element ratios for La/Yb, La/Sm and Gd/Yb also suggested the column to be rich in LREE.Changes in the∑REE of the core sediments also correlated well with climate changes during the last Glacial Maximum(LGM). From 18 to 17 kaBP it was the cold while from 15～12 kaBP it was warming.
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