气候变化领域集成服务门户(CCPortal): From source to mouth: Basin-scale morphodynamics of the Rhine River

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DOI	10.1016/j.earscirev.2019.04.002
	From source to mouth: Basin-scale morphodynamics of the Rhine River
	Frings R.M.; Hillebrand G.; Gehres N.; Banhold K.; Schriever S.; Hoffmann T.
发表日期	2019
ISSN	00128252
卷号	196
英文摘要	In this article we present a unique, detailed, basin-wide, morphological analysis of the Rhine, one of the world's larger rivers. The objectives of this study were to characterize the basin-scale morphodynamics of the Rhine River in the period 1991–2010 by quantifying the downstream fluxes of clay, silt, sand, gravel and cobbles from source to mouth and identifying the sources and sinks of these sediments using sediment budget analyses. From source to mouth, the Rhine traverses four sections with fundamentally different morphodynamic behaviour: the Alpine, impounded, free-flowing and delta section. Sediment fluxes are discontinuous, primarily because of the presence of a glacial lake trapping all sediments from upstream. The lake caused sediment fluxes to be discontinuous already before the Anthropocene. Today's sediment fluxes are strongly influenced by dredging and nourishment operations. From a global perspective, sediment fluxes in the river's headwaters are large, whereas sediment output from the Rhine towards the sea is small. A special feature of the Rhine is the fact that more sediment is transported in upstream direction from the sea into the delta than vice versa. On a basin-scale, nourishment represents the biggest source of gravel and cobbles, and tributaries the biggest source of clay, silt and sand. In the lower Rhine delta, additional large amounts of clay, silt and sand are supplied by the sea. Dredging represents a main sediment sink for all size fractions. For silt and clay, also floodplain deposition and deposition in ports represent major sinks. The Rhine is a typical example of a river in disequilibrium: large parts of the river are subject to erosion or sedimentation. In contrast to other rivers with erosion upstream and deposition downstream, the Rhine has net deposition upstream and net erosion downstream. Although human interventions contributed to the disequilibrium, the pristine Rhine already was in a state of disequilibrium. Even today, natural factors determine the location of the main sedimentation areas. The budget analysis shows that the behaviour of the clay/silt, sand and gravel/cobble fractions strongly differ from each other. A particularity is that in many reaches gravel is deposited, whereas simultaneously sand is being eroded. The budget analysis also shows that sediment dynamics in rivers are much higher than is suggested by echosoundings or transport measurements. This study provides valuable insights into the basin-scale morphodynamics of the Rhine, helps to see smaller-scale studies of parts of the Rhine Basin in a correct perspective, provides a good data basis to improve numerical prediction models, and helps to optimize nourishment, dredging and monitoring strategies in the Rhine. Furthermore, the Rhine represents an excellent reference case for other large river systems for which less data are available. Knowledge gaps of supra-regional importance identified in this study relate to (A) the fundamental disequilibrium of large river systems, (B) the effect of natural and human factors on the future morphodynamic development of the large river systems, (C) the morphodynamic role of sand in gravel-bed rivers and (D) the long-term effects of sediment nourishment. © 2019 Elsevier B.V.
关键词	Disequilibrium Human impact Management Nourishment Rhine River Sand Sediment budget Sediment flux
英文关键词	anthropogenic effect; dredging; fluvial geomorphology; future prospect; morphodynamics; sediment budget; sediment transport; tributary; Netherlands; Rhine Delta; Rhine River
语种	英语
来源期刊	Earth Science Reviews
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/203429
作者单位	Institute of Hydraulic Engineering and Water Resources Management, RWTH Aachen University, Aachen, D 52056, Germany; Department of River Morphology, Sediment Dynamics and Management, Federal Institute of Hydrology, Koblenz, D 56068, Germany
推荐引用方式 GB/T 7714	Frings R.M.,Hillebrand G.,Gehres N.,et al. From source to mouth: Basin-scale morphodynamics of the Rhine River[J],2019,196.
APA	Frings R.M.,Hillebrand G.,Gehres N.,Banhold K.,Schriever S.,&Hoffmann T..(2019).From source to mouth: Basin-scale morphodynamics of the Rhine River.Earth Science Reviews,196.
MLA	Frings R.M.,et al."From source to mouth: Basin-scale morphodynamics of the Rhine River".Earth Science Reviews 196(2019).