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位于中国北方半干旱区的毛乌素沙地对气候变化响应敏感,是研究气候变化的理想区域。通过对毛乌素沙地东南部锦界剖面磁化率、有机质含量、Ca CO3含量的分析,重建了7.5 ka BP以来的气候变化过程。结果显示:中晚全新世毛乌素沙地东南部环境与气候变化可分为3个阶段:7.5~4.6 ka BP,夏季风占主导,气候暖湿,与全新世大暖期对应;4.6~3.3 ka BP,气候突变为干冷并波动频繁;3.3~2.5 ka BP气候以干冷为主。另外,存在5次千年尺度的干旱事件:7.0~6.8 ka BP、6.6~5.7 ka BP、4.6~4.1 ka BP、3.7~3.5 ka BP、3.3~2.5 ka BP。研究区气候变化与全球具有较好的一致性。
The Mu Us Sandland, located in semi-arid northern China, is sensitive to climate change and is an ideal area for studying climate change. Based on the analysis of the magnetic susceptibility, organic matter content and CaCO 3 content in the section of the Kamui section in the southeastern Mu Us desert, the climate change process since 7.5 ka BP has been reconstructed. The results show that the environment and climate change in the mid-late Holocene Mu Us desert can be divided into three stages: 7.5 ~ 4.6 ka BP, dominated by summer monsoon and warm and humid climate, corresponding to the Holocene Megathermal; 4.6 ~ 3.3 ka BP, the climate suddenly changed into dry and cold with frequent fluctuations; the climate of 3.3-2.5 ka BP was mainly dry and cold. In addition, there are five drought events of the millennium scale: 7.0-8.8 ka BP, 6.6-5.7 ka BP, 4.6-4.1 ka BP, 3.7-3.5 ka BP and 3.3-2.5 ka BP. Climate change in the study area has good consistency with the world.