干旱区生态环境知识资源中心(Arid): Variations in geomorphological dynamics in the northern Khangai Mountains, Mongolia, since the Late Glacial period

Arid

DOI	10.1016/j.geomorph.2022.108113
	Variations in geomorphological dynamics in the northern Khangai Mountains, Mongolia, since the Late Glacial period
	Klinge, Michael; Schneider, Florian; Li, Yan; Frechen, Manfred; Sauer, Daniela
通讯作者	Klinge, M
来源期刊	GEOMORPHOLOGY
ISSN	0169-555X
EISSN	1872-695X
出版年	2022
卷号	401
英文摘要	In semi-arid central Mongolia, geomorphological dynamics and forest distribution are commonly regarded as a result of the climatic development over the Holocene. The aim of this study was to detect variations in geomor-phological activity and related eolian, periglacial, colluvial and fluvial processes since the Late Glacial, triggered by climate changes and other factors such as regional lake-level changes, fire events, and human impact. For this purpose, we investigated sediment archives in various relief positions (slope, pediment, valley bottom, dune and lake shore) in a forest-steppe region at the northern edge of the Khangai Mountains. We used a com-bination of geomorphological mapping and sampling of sediments, soils, paleosols, and organic layers. The sam-ples were subjected to sedimentological analysis, luminescence and radiocarbon dating. The ages obtained for the eolian sediments showed that intense eolian activity and periglacial processes occurred during the Last Glacial Period and mitigated after 11 ka. After the Younger Dryas, geomorphological processes de-creased and intensified soil formation indicated a stabilization of the soil surface simultaneously when spreading of forests around 9.5 ka was previously shown in the Khangai Mountains. The early and mid-Holocene were char-acterized by minor geomorphological activity and low fire frequency, as documented by sparseness of charcoal fragments and paleosols in the sediments. Only between 8 ka and 7 ka, reactivation of eolian sand transport was recorded during a drier period. Widespread distribution of late Holocene colluvial, alluvial and eolian sediments containing abundant charcoal, and periglacial features point to a distinct turning point in the Holocene landscape development around 4.5 ka, when substantially enhanced geomorphological activity started. This enhanced geomorphic activity corresponds with a period previously shown to be more humid but also more unstable, and during which forests became more susceptible to severe fire events. After a forest fire, lack of vegetation cover favored intensive erosion. En-hanced geomorphological activity points to a trend towards desertification, which was increasingly aggravated by human impact, since pastoralism emerged latest in the early Bronze Age. Increased production of steppe bio-mass during humid periods led to growth of population and livestock. This growth in turn resulted in overgrazing in drier years. This mechanism probably amplified the aridity signals that were detected in proxies of various paleoenvironmental archives. (C) 2022 Elsevier B.V. All rights reserved.
英文关键词	Mongolia Holocene Sediment archives Paleosols Charcoal Eolian processes Human impact
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000777255900004
WOS关键词	HOLOCENE CLIMATE-CHANGE ; LATE CENOZOIC VOLCANISM ; ENVIRONMENTAL-CHANGES ; VEGETATION CHANGES ; WESTERN MONGOLIA ; DIATOM RECORDS ; FOREST-STEPPE ; GOBI-ALTAY ; NUUR BASIN ; ICE-CORE
WOS类目	Geography, Physical ; Geosciences, Multidisciplinary
WOS研究方向	Physical Geography ; Geology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/392945
推荐引用方式 GB/T 7714	Klinge, Michael,Schneider, Florian,Li, Yan,et al. Variations in geomorphological dynamics in the northern Khangai Mountains, Mongolia, since the Late Glacial period[J],2022,401.
APA	Klinge, Michael,Schneider, Florian,Li, Yan,Frechen, Manfred,&Sauer, Daniela.(2022).Variations in geomorphological dynamics in the northern Khangai Mountains, Mongolia, since the Late Glacial period.GEOMORPHOLOGY,401.
MLA	Klinge, Michael,et al."Variations in geomorphological dynamics in the northern Khangai Mountains, Mongolia, since the Late Glacial period".GEOMORPHOLOGY 401(2022).