Analysis and Modelling of River Meandering


Book Description

This thesis examines the morphological changes of non-tidal meandering rivers at the spatial scale of several meanders. With this purpose, a physics-based mathematical model, MIANDRAS, has been developed for the simulation of the medium-term to long-term evolution of meandering rivers. Application to several real rivers shows that MIANDRAS can properly simulate both equilibrium river bed topography and planimetric changes. Three models of different complexity can be obtained by applying different degrees of simplification to the equations. These models, along with experimental tests and field data, constitute the tools for several analyses. At conditions of initiation of meandering, it is found that river bends can migrate upstream and downstream. This depends on meander wave length and width-to-depth ratio, irrespective of whether the parameters are in the subresonant or the superresonant range.




River Dynamics


Book Description

Rivers are important agents of change that shape the Earth's surface and evolve through time in response to fluctuations in climate and other environmental conditions. They are fundamental in landscape development, and essential for water supply, irrigation, and transportation. This book provides a comprehensive overview of the geomorphological processes that shape rivers and that produce change in the form of rivers. It explores how the dynamics of rivers are being affected by anthropogenic change, including climate change, dam construction, and modification of rivers for flood control and land drainage. It discusses how concern about environmental degradation of rivers has led to the emergence of management strategies to restore and naturalize these systems, and how river management techniques work best when coordinated with the natural dynamics of rivers. This textbook provides an excellent resource for students, researchers, and professionals in fluvial geomorphology, hydrology, river science, and environmental policy.




Meander


Book Description

The course of the Meander is so famously indirect that the river's name has come to signify digression - an invitation Jeremy Seal is duty-bound to accept while travelling the length of it in a one-man canoe. At every twist and turn of his journey, from the Meander's source in the uplands of Central Turkey to its mouth on the Aegean Sea, Seal illuminates his account with a wealth of cultural, historical and personal asides. It is a journey that takes him from Turkey's steppe interior - the stamping ground of such illustrious adventurers as Xerxes, Alexander the Great and the Crusader Kings - to the great port city of Miletus, home of the earliest Western philosophers. Along the way Seal unpicks the history of this remarkable region, but he also encounters a rich assortment of contemporary characters who reveal a rural Turkey on the cusp of change. Above all, this is the story of a river that first brought the cultures of East and West into contact - and conflict - with one another, its banks littered with the spoil of empires, the marks of war, and the detritus of recent industrialisation. At once epic, intimate and insightful, Meander is a brilliant evocation of a land between two worlds.




Theoretical Morphodynamics: River Meandering


Book Description

This monograph discusses the mechanics of Meandering Rivers with the help of the mathematical and modeling tools built up in the previous monograph of the same Authors (monograph 1 of the present series). After introducing the reader to the ubiquitous character of meandering streams, we discuss the hydrodynamics of curved channels with fixed beds and banks. Next, we extend the analysis to account for the mobile character of the bed and show that it gives rise to the alternate sequence of riffles and pools that characterize river meanders. Allowing for the erodible character of the river banks then allows to build up a rational theory of meander formation able to explain most of the features observed in nature: meander growth, migration, skewing, multiple loops, cutoffs and meander belts.




Distributed Acoustic Sensing in Geophysics


Book Description

A comprehensive handbook on state-of-the-art DAS technology and applications Distributed Acoustic Sensing (DAS) is a technology that records sound and vibration signals along a fiber optic cable. Its advantages of high resolution, continuous, and real-time measurements mean that DAS systems have been rapidly adopted for a range of applications, including hazard mitigation, energy industries, geohydrology, environmental monitoring, and civil engineering. Distributed Acoustic Sensing in Geophysics: Methods and Applications presents experiences from both industry and academia on using DAS in a range of geophysical applications. Volume highlights include: DAS concepts, principles, and measurements Comprehensive review of the historical development of DAS and related technologies DAS applications in hydrocarbon, geothermal, and mining industries DAS applications in seismology DAS applications in environmental and shallow geophysics The American Geophysical Union promotes discovery in Earth and space science for the benefit of humanity. Its publications disseminate scientific knowledge and provide resources for researchers, students, and professionals.




River Mechanics


Book Description

This textbook offers a thorough analysis of rivers from upland areas to oceans. It scrutinizes select methods underlining both theory and engineering applications, emphasizing the mechanics of flood wave propagation and sediment transport in rivers. The text covers fundamental principles, engineering analysis, and engineering design, with problems, examples, and case studies throughout. Channel stability and river dynamics are examined in terms of river morphology, lateral migration, aggradation, and degradation. Detailed treatments of riverbank stabilization and engineering methods are provided, while separate chapters cover physical and mathematical models. This essential text presents both the theory and design of measures to reduce flood impact and bank erosion, to improve navigation, and to increase water supply to cities and irrigation canals. Over 100 exercises and nearly twenty case studies make this book an invaluable learning tool for students, and researchers and practitioners will find it a concise resource on the mechanics of rivers.







River Meanders--theory of Minimum Variance


Book Description

The geometry of a meander is that of a random walk whose most frequent form minimizes the sum of the squares of the changes in direction in each unit length. Changes in direction closely approximate a sine function of channel distance. Depth, velocity, and slope are adjusted so as to decrease the variance of shear and the friction factor in a meander over that in an otherwise comparable straight reach of the same river.




Let the Water Do the Work


Book Description

Let the Water Do the Work is an important contribution to riparian restoration. By "thinking like a creek," one can harness the regenerative power of floods to reshape stream banks and rebuild floodplains along gullied stream channels. Induced Meandering is an artful blend of the natural sciences - geomorphology, hydrology and ecology - which govern channel forming processes. Induced Meandering directly challenges the dominant paradigm of river and creek stabilization by promoting the intentional erosion of selected banks while fostering deposition of eroded materials on an evolving floodplain. The river self-heals as the growth of native riparian vegetation accelerates the meandering process. Not all stream channel types are appropriate for Induced Meandering, yet the Induced Meandering philosophy of "going with the flow" can inform all stream restoration projects. Induced meandering strives to understand rivers as timeless entities governed by immutable rules serving their watersheds, setting their own timetables, and coping with their own realities as they carry mountains grain by grain to the sea. Anyone with an interest in natural resource management in these uncertain times should read this book and put these ideas to work.




Meander: Making Room for Rivers


Book Description

Draws on the author's own experiences as a watershed planner, teacher, and activist to tell the story of the Great Lakes region's experiment in restoring a complicated natural system of flowing water.