| 1 | 岱海沉积记录的季风/干旱过渡区全新世适宜期特征显示文摘岱海两支岩芯独立的高分辨率代用指标序列揭示了季风/干旱过渡区全新世适宜期的气候环境特征。研究表明,在约7.9~3.5kaB.P.期间,岱海流域出现植被繁盛、生产力相对增强和降水丰富的状况,显示气候条件相当适宜;而在约10.0~7.6kaB.P.期间,流域气候以相对干燥为特征。这与早先认为的岱海流域全新世初期为适宜期,且降水丰富的结果明显不同。比较岱海与鄂尔多斯-内蒙古高原中部其他湖沼记录,季风/干旱过渡区的气候适宜期基本集中在约8~3kaB.P.的全新世中期,尽管各记录在适宜期的起止时间、表现特征上存在一些差异。这些差异的产生,一方面可能体现了不同的局地地形、植被、水文条件等对区域水热条件的不同反馈,另一方面则可能暗示不同的沉积序列、测年材料之间难以进行精细的对比。沉积序列的连续性、稳定性及高分辨率、测年材料的适用性是进行全新世气候、环境特征研究的前提。 | 孙千里 肖举乐 | 2006 | 第四纪研究2006，26，5： | 71 |
| 2 | Environmental characteristics of Mid-Holocene recorded by lacustrine sediments from Lake Daihai, north environment sensitive zone, China显示文摘Climate proxies, such as total organic carbon and nitrogen (TOC, TN), carbonate content (CaCO3), grain-size and pollen of the sediment core retrieved from enclosed Lake Daihai which lies in the north China environment sensitive zone are analyzed to reconstruct the environment evolution of the area based on high-resolution radiocarbon chronology. The results reveal that the TOC and TN contents of the sediments correlate well with pollen percentage and pollen flux variations during the Holocene, and both reach their peak values simultaneously at 6.7―3.5 ka BP (calendar age, 7.6―3.6 ka BP). Since 6.7 ka BP, both the CaCO3 and organic matter contents of the core have simultaneous variations, and their high values also occur during 6.7―3.5 ka BP. While during 9.0―6.7 ka BP (calendar age, 10―7.6 ka BP) relatively lower level of organic matter content and pollen flux corre- spond to the higher level of carbonate content. The above relations suggest that during 6.7―3.5 ka BP, the productivity and effective precipitation were greatly improved in the lake drainage area, and this would probably strengthen the hydrodynamic conditions, enhancing organic matter, pollen and carbonate inputs from terrestrial sources. Such processes would account for the enrichment of both organic matter and carbonate in the sediments. While during 9.0―6.7 ka BP, the lower level of or- ganic matter, pollen flux but high carbonate content show depressed productivity and declined vege- tation coverage. The higher carbonate content at this stage would have probably resulted from the higher evaporation ratio of the lake water under relatively drier climate conditions. Therefore, it is in- ferred that during 6.7―3.5 ka BP, the climate was more humid with abundant rainfalls and vegetation was more flourishing in the Lake Daihai area. This can be seen as Holocene Climate Optimum (HCO). As a result, this has evident discrepancies with the traditional notion that the HCO occurs at Early Holocene or early Mid-Holocene. | SUN Qianli1,2, ZHOU Jie1, SHEN Ji3, CHEN Peng1,2, WU Feng1,2 & XIE Xiuping1,2 1. State Key Lab of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 2. Graduate University of Chinese Academy of Sciences, Beijing 100039, China 3. Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China | 2006 | Science China Earth Sciences2006，49，9： | 11 |
| 3 | 全新世以来岱海湖泊沉积与环境演变显示文摘岱海湖泊位于半干旱区东部边缘及东亚夏季风的尾闾区,生态环境体系脆弱,气候和环境变化敏感,是研究环境演变的理想地区。全新世以来,由于气候的变化和季风的强弱而引起的气候带界限的迁移极为频繁,使得本区成为一个气候敏感区。利用内陆封闭湖泊沉积物连续性强、分辨率高、对气候敏感等特点,以单一流域化学风化记录恢复了岱海地区全新世以来的环境演化过程。根据岱海湖泊岩心沉积物的粒度变化、孢粉来源和分布以及有机碳及其同位素指标序列分析,结合210Pb测定的沉积速率,讨论了岱海全新世以来的气候环境演化过程。从空间尺度、不同时间尺度与其他研究结果的对比以及代用指标与气候要素的关系研究等几个方面总结了全新世以来高原湖泊岱海沉积与环境演变研究的主要成果。 | 杜青松 常诗楠 李志华 张玲玲 张鹏飞 | 2013 | 西北地质2013，46，3： | 4 |
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