中文摘要：

通过乌鲁木齐附近柴窝堡湖钻孔岩芯的粒度、有机质含量、化学元素以及同位素等多项分析，开展了研究区近150年来的气候环境演化研究。通过沉积记录与器测气象资料比较，认为沉积物的有机质含量反映了流域降水的变化，而有机质碳同位素的变化则与温度相关。在运用有序样品最优聚类分析对沉积物地球化学元素序列进行阶段划分的基础上，综合粒度、有机质含量以及同位素等多环境代用指标的分析，恢复了不同阶段的气候环境信息。结果表明，1860—1910A．D．，各环境指标显示当时湖泊水位较高，湖水较深，显示偏冷、偏湿的气候环境特征。1910～1950A．D．，粒度、地球化学元素、有机质、磁化率等指标波动明显，虽然有机碳同位素值有所升高，但仍然总体偏负，显示该阶段湖泊环境总体上波动强烈，气候不稳定。其中约1920A．D．左右，粒度显示突然变化，有机碳同位素、烧失量、元素含量等也均发生了显著的波动，指示明显气候环境事件的存在。1950A．D．以来，钻孔岩芯的磁化率升高，重金属元素含量以及总磷含量呈现明显富集，而有机质及其碳同位素变化却与器测温度和降水变化一致，指示了近期气候和人类活动对湖泊环境的影响。

英文摘要：

A sediment core recovered from Chaiwopu Lake was analyzed for grain size, organic matter content, δ^13C of organic matter and magnetic susceptibility to reveal the history of changes in the regional climate and environment over the past 150 years. Based on modern observations, the content of organic matter in the sediments is interpreted to reflect the regional precipitation and the organic δ^13C is inferred to reflect air temperature. Ordinal sample optimal cluster analysis was used to divide the element-content sequence of the sediment core into several stages characterizing the pattern of changes in the climate and environment. The data indicate that the lake displayed high levels and the climate was slightly cold and wet 1860 - 1910A. D. From 1910A. D. to 1950A. D., grain size, geochemical proxies, organic matter content and magnetic susceptibility all showed significant fluctuations, and δ^13C continuously became heavier, suggesting the variability of the lake environment and the instability of the regional climate. Around 1920A. D., grain size displayed a sudden shift, and δ^13C , loss on ignition and element contents exhibited obvious variations, implying the occurrence of abrupt changes in the climate and environment. During the past 50 years, magnetic susceptibility was high, and heavy metals and total phosphorus contents were enriched in the lake sediments, denoting the impact of human activities on the environment of the lake region. Changes in the organic matter content and organic δ^13C are consistent with variations in the observed temperature and precipitation, indicating the combined effect of the recent climate changes and human activities on the lake environment.