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测定了洱海沉积物中常量和微量元素的含量，利用因子分析方法，识别了控制沉积物化学组成的三个主要因子：流域侵蚀因子、早期成岩因子和湖泊内生碳酸钙沉淀因子。进一步的研究还发现，流域侵蚀因子和湖泊内生碳酸钙沉淀因子的因子得分曲线可分别作为气候干湿和冷暖变化的代用曲线，从而为古气候重建提供了一条有效的新途径。结合沉积物柱210Pb和137Cs计年结果，初步评价了600多年来洱海区域气候及环境演化历史，揭示了该区暖平与冷湿相交替的气候演替类型。16世纪中期～19世纪末期的冷湿状况可能是现代小冰期在洱海地区的反映。
The contents of major and trace elements in sediments of Erhai Lake were determined. Three major factors controlling the chemical composition of sediments were identified by factor analysis: river basin erosion factors, early diagenesis factors and lake endogenous calcium carbonate precipitation factors. Further research also found that the factor score curve of basin erosion factor and lake endogenous calcium carbonate precipitation factor can be taken as the surrogate curve of climate change of wet, dry and warm, respectively, which provides an effective new approach for palaeoclimate reconstruction. Based on the 210Pb and 137Cs dating results of sediment columns, the climate and environmental evolution history of Erhai Lake in the past 600 years have been preliminary evaluated, and the types of climate successions alternating with warm and cold phases have been revealed. The cold and wet conditions from the middle of the 16th century to the end of the 19th century may be the reflection of the modern small ice age in Erhai Lake.