| 松嫩平原中更新世以来气候干旱化 |
| |
| 引用本文： | 赵倩,谢远云,郝冬梅,迟云平,康春国,吴鹏,刘硕.松嫩平原中更新世以来气候干旱化[J].沉积学报,2022,40(6):1702-1717. |
| |
| 作者姓名： | 赵倩 谢远云 郝冬梅 迟云平 康春国 吴鹏 刘硕 |
| |
| 作者单位： | 1.哈尔滨师范大学地理科学学院, 哈尔滨 150025 |
| |
| 基金项目： | 国家自然科学基金41871013黑龙江省自然科学基金LH2020D009 |
| |
| 摘 要： | 哈尔滨黄土位于欧亚黄土带最东端,是研究气候干旱化的理想载体,对于重建松嫩平原气候干旱化历史及完善亚洲内陆干旱化东进进程具有重要意义。然而,松嫩平原干旱化的相关研究相当薄弱,黄土与区域构造—气候—水系演化之间的耦合关系尚未明确。对哈尔滨黄土—古土壤序列进行了沉积学特征分析以及粒度、磁化率、总有机碳和Sr-Nd同位素组成测试,结合粒度端元和小波分析,对松嫩平原气候干旱化历史及驱动机制进行研究。结果表明:受高纬度寒冷气候影响,哈尔滨黄土—古土壤序列的沉积特征与其他地区存在显著差异,潜育化的沉积环境是古土壤层磁化率呈现低值的主控因素；哈尔滨黄土堆积的出现指示了松嫩平原干旱化和松嫩沙地的发育始于~460 ka；黄土大于63 μm以及EM3端元组分共同指示了380 ka和300 ka两次明显的干旱化加剧和沙地扩张事件；TOC和Sr同位素指标揭示了这种干旱化加剧的现象一直持续到180 ka。此后,松嫩平原的气候逐渐趋于暖湿。研究显示,全球气候变冷（冰量的扩增）—区域构造（松辽分水岭隆起）—水系演化（松辽水系的变迁）共同驱动了松嫩平原气候干旱化。上述认识对松嫩平原的生态与社会经济的可持续发展具有重要意义。
|
| 关 键 词： | 哈尔滨黄土 松嫩平原 气候干旱化 粒度 端元分析 小波分析 |
| 收稿时间： | 2021-02-28 |
Climatic Aridification in Songnen Plain Since the Middle Pleistocene from Harbin Loess Records |
| |
| Institution: | 1.School of Geographical Sciences, Harbin Normal University, Harbin 150025, China2.Heilongjiang Key Laboratory of Geographical Environment Monitoring and Spatial Information Service in Cold Region, Harbin Normal University, Harbin 150025, China3.Department of Geography, Harbin University, Harbin 150086, China |
| |
| Abstract: | The Harbin loess is located in the easternmost part of the Eurasian loess belt. It is an ideal material for reconstructing the history of aridification of the Songnen Plain and determining the eastward advance of inland Asia. However, research on aridification of the climate in the Songnen Plain is quite weak. The relationships between aridification, tectonism, climate and drainage evolution in the area are currently poorly understood. In this study, these sedimentary characteristics, grain-size, magnetic susceptibility, total organic carbon and Sr-Nd isotopes are presented, combined with grain size end-member and wavelet analysis, to examine the history and driving mechanism of climate aridification in the Songnen Plain. It was found that due to the high-latitude cold climate, deposition of the Harbin loess-paleosol sequence was significantly different from that in other regions. The gleization sedimentary environment is the main controlling factor for the low magnetic susceptibility of the paleosol layer； the appearance of the Harbin loess indicates the climate aridification of the Songnen Plain. The Songnen sandy land began to develop at about 460 ka； loess >63 μm and the EM3 end member component together clearly indicate the occurrence of two aridification and sandy expansion events at 380 ka and 300 ka. The Sr and Nd isotopes and TOC indicators reveal that the aridification phenomenon continued until 180 ka, after which the climate of the Songnen Plain gradually became warmer and wetter. Global climate cooling （enlargement of ice areas）, regional tectonism （uplift of the Songliao watershed）, and drainage change （altered Songliao water system） were collectively responsible for aridification in the Songnen Plain. This study is of great significance to the sustainable developmentof the ecology and social economy of the Songnen Plain. |
| |
| Keywords: | |
|
| 点击此处可从《沉积学报》浏览原始摘要信息 |
| 点击此处可从《沉积学报》下载免费的PDF全文 |
|
