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Fine Sediment Dynamics in the Marine Environment
1200
Book reviews / Estuarine, Coastal and Shelf Science 57 (2003) 1195–1201
volumes, as I am sure they are going to find information and references that they do not know about and which will be a great use to their research programmes. I hope such volumes bring Indian scientists into the mainstream of oceanographic research, as we will all benefit from such interactions in studying this ocean; one of the most fascinating and intriguing on Earth. Paul Tyler University of Southampton Southampton, UK doi:10.1016/S0272-7714(03)00092-1
Fine Sediment Dynamics in the Marine Environment, edited by J.C. Winterwerp and C. Kranenburg; Elsevier, Amsterdam, 2002, 713 pages, Euro 189.00, ISBN 0-44451136-9. Fine-grained cohesive sediment, or mud to most people, occurs worldwide in fluvial, estuarine and coastal environments. However, despite the widespread occurrence and importance of muddy sediments, many aspects concerning the transport and deposition of mud are still poorly understood. ÔFine Sediment Dynamics in the Marine EnvironmentÕ does not set out to be an introductory text, but instead represents an in-depth look at cohesive sediment dynamics based primarily on the proceedings of the sixth INTERCOH conference. These conferences, originally started by Professor Mehta, have covered recent progress on the physical and engineering aspects of cohesive sediment transport. The INTERCOH-2000 conference was integrated with the final workshop of the COSINUS project, which was funded under the European MAST-3 programme. As such, the book presents an excellent coverage of the various aspects of mud dynamics from a wide range of workers. These workers come from both industry and academic organisations around the world including, inter alia, countries such as the United States, France, the Netherlands, Germany, Denmark, Russia and Japan. The book focuses on the behaviour and modelling of concentrated benthic suspensions and the papers within it cover the following areas:
sediment–turbulence interaction; flocculation and settling velocity; high concentration mud suspensions; processes in the bed—consolidation; processes on the bed—erosion; field observations on mud dynamics; instrumentation; and numerical modelling.
Chapter 1 provides an overview of the COSINUS project and is followed by five summaries of the project tasks. These include papers on turbulent interactions, flocculation, concentrated benthic suspension layers, bed dynamics measurements and modelling. The last paper in this chapter, which compares five numerical mud transport models, is particularly interesting for engineers and consultants. The paper covers aspects such as the inherent limitations of models, inconsistencies between models and the importance of correct parameterisation. Chapter 2 presents a number of papers concerned with highly concentrated mud suspensions. The papers cover sediment fluxes, turbidity maxima, entrainment, turbulent mixing and interfacial instabilities in lutoclines. These aspects are covered through field measurements in a number of estuaries, laboratory measurements and modelling approaches. The last paper in this chapter is again particularly interesting. It deals with dimensionless scaling parameters for high concentration mud suspensions in tidal flow and discusses the collapse of mud suspension vertical profiles leading to the formation of fluid mud. Chapter 3 also covers processes within the water column, namely aspects relating to flocculation and settling velocities. The papers cover detailed laboratory flume measurements, observations of turbidity maxima in estuaries and the numerical modelling of flocculation. The first two papers link laboratory observations with known occurrences in the field, particularly with regard to flocculation processes in the turbidity maximum. The penultimate paper in this section shows that more complex flocculation models do not necessarily provide any better simulation of measured conditions in the field. Recognising the inherent difficulties of instruments, which disrupt the very process they are trying to measure, the final paper in this chapter describes a stand alone non-disruptive device for measuring in situ floc dimensions. Chapter 4 deals with processes in and on the bed, namely consolidation and erosion. The first paper shows the limited effects of biological factors on bed erodibility in a freshwater system, based on in situ erosion measurements. The next two papers examine the generation and destabilising effect of gas bubbles within sediments. The following two papers are concerned with modelling, firstly of consolidation and secondly of vertical exchange processes. The last two papers of this chapter report on the stabilisation of sediment by biological influences. Interestingly, the final paper demonstrates the role of EPS in increasing erosion resistance and provides a physical explanation of this on the basis of Low Temperature Scanning Electron Microscopy (LTSEM). Chapter 5 contains papers on instrumentation and field observations of mud dynamics. The first three
Book reviews / Estuarine, Coastal and Shelf Science 56 (2003) 1195–1201
papers of this chapter cover the role of biological factors in mud dynamics, which although important, are often relatively understudied. The first paper elucidates the role of extracellular carbohydrate and microbenthic populations in controlling temporal variations in estuarine suspended sediment concentrations. The next paper describes the impacts of vegetation on hydrodynamics and turbidity based on both field and laboratory studies. The third paper details with the effect of mangroves on waves, tides and sedimentation. Paper 6 deals with the varying influence of tidal and freshwater flows on net sediment transport in an estuary. The final paper investigates estuarine mud bank formation, using a novel large-scale natural laboratory facility constructed within an estuary. Although some of previous chapters cover modelling, Chapter 6 is wholly devoted to the use of numerical modelling in the simulation of mud transport and deposition. There is a good coverage of various aspects of numerical modelling and like many of the previous chapters there are contributions from around the world, including Holland, China, the UK and France. Several papers describe the application of commercially available modelling packages. For example, the first paper describes the use of TELEMAC 3D in the Loire and illustrates the sensitivity of results to the settling velocity formulation. Similarly, Paper 7 describes the use of the MIKE 3 model to describe mud transport in the Tamar
1201
and illustrates the importance of flocculation and other variables. There are also a number of papers, which describe the development of new modelling tools. These include the development of: a process-based model for predicting the sediment distribution (Paper 4); a finiteelement model for cohesive sediment transport (Paper 6); a new numerical model for mud transport (Paper 8); and a 1D sediment transport model (Paper 10). The penultimate paper in this chapter (Paper 9) makes a numerical assessment of source (erodibility) and sink (sedimentation) factors for cohesive sediments and indicates the importance of bed consolidation and flocculation factors. This book represents a must for libraries and dedicated researchers in this field, as it covers the state of the art in terms of cohesive sediment dynamics. The various papers provide useful comparative data and illustrate the importance of correct parameterisation within models. It is not an undergraduate textbook. That said, certain papers provide up-to-date further reading for some courses, and many of the papers are easy to follow, even for a non-specialist. Nigel Pontee ABP Marine Environmental Research Ltd Southampton, UK doi:10.1016/S0272-7714(03)00094-5
Book reviews / Estuarine, Coastal and Shelf Science 57 (2003) 1195–1201
volumes, as I am sure they are going to find information and references that they do not know about and which will be a great use to their research programmes. I hope such volumes bring Indian scientists into the mainstream of oceanographic research, as we will all benefit from such interactions in studying this ocean; one of the most fascinating and intriguing on Earth. Paul Tyler University of Southampton Southampton, UK doi:10.1016/S0272-7714(03)00092-1
Fine Sediment Dynamics in the Marine Environment, edited by J.C. Winterwerp and C. Kranenburg; Elsevier, Amsterdam, 2002, 713 pages, Euro 189.00, ISBN 0-44451136-9. Fine-grained cohesive sediment, or mud to most people, occurs worldwide in fluvial, estuarine and coastal environments. However, despite the widespread occurrence and importance of muddy sediments, many aspects concerning the transport and deposition of mud are still poorly understood. ÔFine Sediment Dynamics in the Marine EnvironmentÕ does not set out to be an introductory text, but instead represents an in-depth look at cohesive sediment dynamics based primarily on the proceedings of the sixth INTERCOH conference. These conferences, originally started by Professor Mehta, have covered recent progress on the physical and engineering aspects of cohesive sediment transport. The INTERCOH-2000 conference was integrated with the final workshop of the COSINUS project, which was funded under the European MAST-3 programme. As such, the book presents an excellent coverage of the various aspects of mud dynamics from a wide range of workers. These workers come from both industry and academic organisations around the world including, inter alia, countries such as the United States, France, the Netherlands, Germany, Denmark, Russia and Japan. The book focuses on the behaviour and modelling of concentrated benthic suspensions and the papers within it cover the following areas:
sediment–turbulence interaction; flocculation and settling velocity; high concentration mud suspensions; processes in the bed—consolidation; processes on the bed—erosion; field observations on mud dynamics; instrumentation; and numerical modelling.
Chapter 1 provides an overview of the COSINUS project and is followed by five summaries of the project tasks. These include papers on turbulent interactions, flocculation, concentrated benthic suspension layers, bed dynamics measurements and modelling. The last paper in this chapter, which compares five numerical mud transport models, is particularly interesting for engineers and consultants. The paper covers aspects such as the inherent limitations of models, inconsistencies between models and the importance of correct parameterisation. Chapter 2 presents a number of papers concerned with highly concentrated mud suspensions. The papers cover sediment fluxes, turbidity maxima, entrainment, turbulent mixing and interfacial instabilities in lutoclines. These aspects are covered through field measurements in a number of estuaries, laboratory measurements and modelling approaches. The last paper in this chapter is again particularly interesting. It deals with dimensionless scaling parameters for high concentration mud suspensions in tidal flow and discusses the collapse of mud suspension vertical profiles leading to the formation of fluid mud. Chapter 3 also covers processes within the water column, namely aspects relating to flocculation and settling velocities. The papers cover detailed laboratory flume measurements, observations of turbidity maxima in estuaries and the numerical modelling of flocculation. The first two papers link laboratory observations with known occurrences in the field, particularly with regard to flocculation processes in the turbidity maximum. The penultimate paper in this section shows that more complex flocculation models do not necessarily provide any better simulation of measured conditions in the field. Recognising the inherent difficulties of instruments, which disrupt the very process they are trying to measure, the final paper in this chapter describes a stand alone non-disruptive device for measuring in situ floc dimensions. Chapter 4 deals with processes in and on the bed, namely consolidation and erosion. The first paper shows the limited effects of biological factors on bed erodibility in a freshwater system, based on in situ erosion measurements. The next two papers examine the generation and destabilising effect of gas bubbles within sediments. The following two papers are concerned with modelling, firstly of consolidation and secondly of vertical exchange processes. The last two papers of this chapter report on the stabilisation of sediment by biological influences. Interestingly, the final paper demonstrates the role of EPS in increasing erosion resistance and provides a physical explanation of this on the basis of Low Temperature Scanning Electron Microscopy (LTSEM). Chapter 5 contains papers on instrumentation and field observations of mud dynamics. The first three
Book reviews / Estuarine, Coastal and Shelf Science 56 (2003) 1195–1201
papers of this chapter cover the role of biological factors in mud dynamics, which although important, are often relatively understudied. The first paper elucidates the role of extracellular carbohydrate and microbenthic populations in controlling temporal variations in estuarine suspended sediment concentrations. The next paper describes the impacts of vegetation on hydrodynamics and turbidity based on both field and laboratory studies. The third paper details with the effect of mangroves on waves, tides and sedimentation. Paper 6 deals with the varying influence of tidal and freshwater flows on net sediment transport in an estuary. The final paper investigates estuarine mud bank formation, using a novel large-scale natural laboratory facility constructed within an estuary. Although some of previous chapters cover modelling, Chapter 6 is wholly devoted to the use of numerical modelling in the simulation of mud transport and deposition. There is a good coverage of various aspects of numerical modelling and like many of the previous chapters there are contributions from around the world, including Holland, China, the UK and France. Several papers describe the application of commercially available modelling packages. For example, the first paper describes the use of TELEMAC 3D in the Loire and illustrates the sensitivity of results to the settling velocity formulation. Similarly, Paper 7 describes the use of the MIKE 3 model to describe mud transport in the Tamar
1201
and illustrates the importance of flocculation and other variables. There are also a number of papers, which describe the development of new modelling tools. These include the development of: a process-based model for predicting the sediment distribution (Paper 4); a finiteelement model for cohesive sediment transport (Paper 6); a new numerical model for mud transport (Paper 8); and a 1D sediment transport model (Paper 10). The penultimate paper in this chapter (Paper 9) makes a numerical assessment of source (erodibility) and sink (sedimentation) factors for cohesive sediments and indicates the importance of bed consolidation and flocculation factors. This book represents a must for libraries and dedicated researchers in this field, as it covers the state of the art in terms of cohesive sediment dynamics. The various papers provide useful comparative data and illustrate the importance of correct parameterisation within models. It is not an undergraduate textbook. That said, certain papers provide up-to-date further reading for some courses, and many of the papers are easy to follow, even for a non-specialist. Nigel Pontee ABP Marine Environmental Research Ltd Southampton, UK doi:10.1016/S0272-7714(03)00094-5