末次冰消期以来黄河首曲流域气候变化与地表过程相互关系  

Interrelationships between climate change and surface processes in the First Meander of the Yellow River since the Last Deglaciation

作　　者：葛健辉 刘冰 徐宇杰 孙爱军 汪克奇 李冬雪 赵晖 Ge Jianhui;Liu Bing;Xu Yujie;Sun Aijun;Wang Keqi;Li Dongxue;Zhao hui(Key Laboratory of Desert and Desertification,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China;University of Chinese Academy of Sciences,Beijing 100049,China;Ministry of Education Key Laboratory of Western China's Environmental Systems,College of Earth and Environmental Sciences,Lanzhou University,Lanzhou 730000,China)

机构地区：[1]中国科学院西北生态环境资源研究院中国科学院沙漠与沙漠化重点实验室,甘肃兰州730000 [2]中国科学院大学,北京100049 [3]兰州大学资源环境学院西部环境教育部重点实验室,甘肃兰州730000

出　　处：《中国沙漠》2024年第2期121-132,共12页Journal of Desert Research

基　　金：第二次青藏高原综合科学考察研究项目(2019QZKK0601-02);国家自然科学基金项目(41977393)。

摘　　要：黄河首曲是世界高海拔地区生物多样性丰富和生态变化敏感的地区,其环境演变过程如何响应区域气候变化具有重要的科学意义。针对该区末次冰消期以来气候环境重建结果的分歧,以目前已发表的多载体记录为基础,独立集成区域气候变化的框架性过程和地表环境演变历史,进而探讨两者的相互关系。结果表明:(1)该区在13~6 ka气温和湿度持续增加,10~6 ka为气候最优期,6 ka以后气温和湿度逐渐下降,气候变冷变干。(2)18~11 ka地表过程以河湖相过程为主,风沙活动非常弱;11~8 ka河湖沉积过程减弱,风沙活动增强;8~3 ka古土壤大规模发育;3 ka以来广泛发育草甸土。(3)区域地表环境变化过程与气候变化之间存在非同步变化,6 ka以前气候变化对区域地表过程呈正向驱动,6 ka以后对区域地表过程呈负向驱动。基于现代和晚全新世草甸土壤粒度的比较,发现草甸土壤的发育是气候变冷变干背景下风成物质不断加积的产物,进一步暗示区域土壤发育与气候变化间的复杂关系。The First Meander of the Yellow River,an area rich in biodiversity,is highly sensitive to ecological changes in the world's high-altitude regions,in where the environmental evolution how responds to regional climate change is of great important scientific significance.In view of the reconstructed results divergence of climate/environment since the last deglaciation,we individually synthesized the framework process of regional climatic change and the history of earth surface environmental evolution,as well as further discuss the relationship between them,with the aid of the published multi-archive records.The results indicated that the regional climate became warmer and wetter during the period of 13-6 ka,with the climatic optimum of 10-6 ka,afterwards,the regional climate tended to be cold-dry owing to the declined temperature and humidity.The regional earth surface process was dominated by the fluvio-lacustrine sediments during 18-11 ka,accompanying with the weakest aeolian activity,whereas the aeolian activity began enhanced from 11 ka to 8 ka,along with the weakened fluvio-lacustrine process.In 8-3 ka,the paleosol is unprecedentedly developed and alpine meadow is extensively formed thereafter.An asynchronous relationship was detected between regional surface environmental and climate change,in detail,climate change positively drove regional surface processes prior to 6 ka,whereas it exerted a negative influence hereafter.Additionally,we concluded that meadow soil is a product of continuous accumulation of aeolian material under the context of gradually cold and dry conditions,by comparing modern and late Holocene meadow soil particle sizes,which implying a complex relationship between regional soil development and climate change.

关 键 词：末次冰消期 黄河首曲 气候变化 地表过程 相互关系 

分 类 号：P532[天文地球—古生物学与地层学]