This study presents the record of paleoenvironmental evolution results from a radiocarbon-dated 1.54m-long lacustrine sediment sequence in south Leizhou Peninsula. Measurement of grain size, magnetic susceptibility (MS), total nitrogen (TN), total or-ganic carbon (TOC), atomic TOC/TN (C/N) and color reflectance values was carried out in order to reconstruct the climate span-ning the interval 10.5~6.5cal ka BP. Three distinct stages can be identified as follows: ①10.5~6.5 cal ka BP, a shallow lake level and relatively dry climate dominated this area. ②The interval from 9.5~7.2cal ka BP was characterized by a relatively high lake level and humid climate. ③During 7.2~6.5cal ka BP, lake level was relatively shallow with a relatively dry climate. Indian monsoon was more responsible for precipitation variability in this area, which was interconnected with average monthly solar radiation in summer and ITCZ migration. Red noise spectrum analysis of proxies shows centennial to millennia time scale cycles, which suggests that the envi-ronmental evolution was probably sensitive to the secular solar activity.%对雷州半岛南部徐闻县九亩村一段1.54m厚的湖相沉积剖面进行粒度、磁化率、色度及有机碳氮分析,结合AMS14C测年结果,重建了该地区10.5~6.5cal ka BP的气候环境变化.共分为3个阶段:①10.5~9.5cal ka BP,湖泊水体较浅,气候较干燥;②9.5~7.2cal ka BP,湖泊水位较高,环境稳定,气候较湿润;③7.2~6.5cal ka BP,湖水相对变浅,气候相对阶段②干燥.雷州半岛地区降水变化与印度季风演变模式一致,可与北半球夏季平均太阳辐射及其影响下热带辐合带(ITCZ)的移动进行对比,指标时间序列的红外噪声谱分析结果表明,存在千年—百年的准周期,反映了研究区气候环境变化对太阳活动的响应.
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