气候变化领域集成服务门户(CCPortal): Morphodynamic Characteristics of a Complex Anabranching System in the Qinghai-Tibet Plateau and the Implications for Anabranching Stability

CCPortal

DOI	10.1029/2022JF006788
	Morphodynamic Characteristics of a Complex Anabranching System in the Qinghai-Tibet Plateau and the Implications for Anabranching Stability
	Guo, Xiwei; Gao, Peng; Li, Zhiwei
发表日期	2023
ISSN	2169-9003
EISSN	2169-9011
卷号	128 期号:2
英文摘要	The understanding of fluvial processes controlling morphological adjustments and stability of anabranching rivers remains incomplete. Focusing on a complex anabranching system in the Upper Yellow River, this study quantifies the morphological characteristics and lateral dynamics of islands and channels in four reaches over a 56-km river course from 1986 to 2017. Using five heuristic anabranching structures derived from the studied anabranching system, we estimate sediment transport capacities and assess their implications for the morphodynamics of anabranching rivers. These results show that the system exhibited a highly complex pattern featuring high channel multiplicity and dominance of islands. Over the study periods, the system exhibited an accreting disequilibrium state, which was highlighted by spatiotemporally diverse and dynamic patterns of islands. Morphological changes in islands were dominated by expansion and shrinkage, which caused more areal changes than other modes of change, including coalescence, cleavage, new island formation, and elimination. These processes controlled the creation and elimination of small anabranches, whereas the size and morphology of large channels remained comparatively stable, which maintained the stability of this anabranching pattern. The stability of the anabranching pattern is further supported by estimations of transport capacity in that the main channels transport most sediments and in that excess development of small anabranches promotes sediment deposition within the system. Overall, this study provides new insight into the morphodynamic properties of anabranching rivers, demonstrating that, instead of channel numbers, island dynamics and interactions with channels are controls of the evolutionary processes and stability of anabranching rivers.
关键词	anabranching river island dynamics accretion and erosion flow efficiency channel stability
英文关键词	CHANNEL PLANFORM CHANGE; UPPER COLUMBIA RIVER; ZOIGE BASIN; BRITISH-COLUMBIA; FLUVIAL DYNAMICS; PATTERNS; FLOODPLAIN; MORPHOLOGY; EVOLUTION; ISLAND
WOS研究方向	Geosciences, Multidisciplinary
WOS记录号	WOS:000933239100001
来源期刊	JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/283500
作者单位	Syracuse University; Wuhan University
推荐引用方式 GB/T 7714	Guo, Xiwei,Gao, Peng,Li, Zhiwei. Morphodynamic Characteristics of a Complex Anabranching System in the Qinghai-Tibet Plateau and the Implications for Anabranching Stability[J],2023,128(2).
APA	Guo, Xiwei,Gao, Peng,&Li, Zhiwei.(2023).Morphodynamic Characteristics of a Complex Anabranching System in the Qinghai-Tibet Plateau and the Implications for Anabranching Stability.JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE,128(2).
MLA	Guo, Xiwei,et al."Morphodynamic Characteristics of a Complex Anabranching System in the Qinghai-Tibet Plateau and the Implications for Anabranching Stability".JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE 128.2(2023).