Gravel-Bed Rivers (eBook)

Process and Disasters

Daizo Tsutsumi, Jonathan B. Laronne (Herausgeber)

eBook Download: PDF

2017
John Wiley & Sons (Verlag)
978-1-118-97141-3 (ISBN)

Infos

With contributions from key researchers across the globe, and edited by internationally recognized leading academics, Gravel-bed Rivers: Processes and Disasters presents the definitive review of current knowledge of gravel-bed rivers. Continuing an established and successful series of scholarly reports, this book consists of the papers presented at the 8th International Gravel-bed Rivers Workshop. Focusing on all the recent progress that has been made in the field, subjects covered include flow, physical modeling, sediment transport theory, techniques and instrumentation, morphodynamics and ecological topics, with special attention given to aspects of disasters relevant to sediment supply and integrated river management. This up-to-date compendium is essential reading for geomorphologists, river engineers and ecologists, river managers, fluvial sedimentologists and advanced students in these fields.

Daizo Tsutsumi, Disaster Prevention Research Institute, Kyoto University, Kyoto, Japan

Jonathan B. Laronne, Department of Geography and Environmental Development, Ben Gurion University of the Negev, Beer Sheva, Israel

Inhalt

Title Page 5
Copyright Page 6
Contents 7
List of Contributors 21
Preface 27
Chapter 1 Computational Models of Flow, Sediment Transport and Morphodynamics in Rivers 31
1.1 Introduction 31
1.2 Numerical Simulations in Rivers 32
1.2.1 Level 0: Reduced Complexity Models 32
1.2.2 Level 1: Diffusion Models 35
1.2.3 Level 2: Models Based on Solving the Shallow-Water Equations 37
1.2.4 Level 3: Unsteady Reynolds-averaged Navier–Stokes 38
1.2.5 Level 4: Large-Eddy Simulations 41
1.2.6 Level 5: Direct Numerical Simulations 42
1.3 Choosing the Right Modeling Approach 43
1.3.1 Models as Research Tools 43
1.3.2 Heuristics: How to Select a Modeling Approach 45
1.4 Next Steps in Modeling 50
1.4.1 High-Fidelity Modeling 50
1.4.2 Model Synthesis 52
1.5 Concluding Questions 53
Acknowledgments 54
References 54
Discussion 59
Chapter 2 Boulder Effects on Turbulence and Bedload Transport 63
2.1 Boulders in the Riverine Continuum 63
2.2 Scope and Objectives of the Study 66
2.3 Dataset Selection and Methodology 69
2.3.1 Dataset Selection 69
2.3.2 Experimental Setup and Measurement Techniques 71
2.3.3 Data Post-Processing 75
2.4 Mean Flow Field Around a Single, Wall-Mounted Boulder 77
2.4.1 Mean Streamwise Flow Velocity Field 77
2.4.2 Distribution of u* Around the Boulder 79
2.5 Mean Vortex Structure Around a Wall-Mounted Boulder 81
2.6 Collective Effects of the Boulder Array 83
2.7 Sediment Transport Within a Boulder Array 86
2.7.1 Qualitative Assessment of Flow and Sediment Deposition Patterns 86
2.7.2 Sediment Deposition Patterns around Boulders 88
2.7.3 Correspondence of Sediment Deposition and Vortex Structure Areas 89
2.8 Morphology of Depositional Patches Around Boulders 90
2.9 Concluding Remarks 91
Notation and Abbreviations 93
Acknowledgments 95
References 95
Discussion 101
Chapter 3 Granular Flows Applied to Gravel-Bed Rivers: Particle-Scale Studies of the Mobilization of a Gravel Bed by the Addition o... 103
3.1 Introduction 103
3.1.1 Governing Parameters Revealed Through Experimental Flume Studies 103
3.1.2 Potential Physical Mechanisms Governing the Mobilizing Behaviors 105
3.2 Insights from Rheological Models of Dry Dense Granular Flows 106
3.2.1 Rheology of Dense Granular Flows 107
3.2.2 Rheology of Dense Granular Mixtures 108
3.2.3 Rheology of Dense Granular Mixtures Applied to the Mobility Problem of Bedload Mixtures 109
3.3 Discrete Element Model Simulations of Bimodal Mixtures in Bedload Transport 111
3.3.1 Our DEM model 112
3.3.2 Simulation Procedures and Results 115
3.4 Conclusions 118
Notation and Abbreviations 119
Acknowledgments 122
References 122
Discussion 124
Chapter 4 Particle Motions and Bedload Theory: The Entrainment Forms of the Flux and the Exner Equation 127
4.1 Introduction 127
4.2 Sediment Ensembles and Rarefied Conditions 129
4.2.1 Ensembles and Ensemble Distributions 129
4.2.2 Rarefied Versus Continuum Conditions 131
4.3 Entrainment Forms of the Flux and the Exner Equation 131
4.3.1 Nonlocal Behavior 131
4.3.2 Instantaneous Flux 132
4.3.3 The Exner Equation 135
4.4 Distributions of Hop Distances and Travel Times 136
4.4.1 Disentrainment Rates 136
4.4.2 Experimental Measurements 139
4.5 The Meaning of Continuous Functions Applied to Conditions of Rarefied Transport 141
4.6 Conclusions 143
Notation 144
Acknowledgments 145
References 145
Discussion 148
Chapter 5 Revisiting the Morphological Approach: Opportunities and Challenges with Repeat High-Resolution Topography 151
5.1 Introduction 151
5.2 The Morphological Approach: a Primer 152
5.2.1 Transport Rates from Sediment Budgeting 154
5.2.2 Transport Rates from Path Lengths 154
5.3 Applying a Morphological Approach with HRT 158
5.3.1 Digital Elevation Models and DEMs of Difference 160
5.3.2 Extracting DEMs from Hyperscale Point Clouds 165
5.3.3 What More Might Hyperscale Data Reveal? 167
5.3.4 Case Study: High Frequency Morphodynamics of the Braided Rees River 171
5.4 Discussion 175
5.4.1 New Technologies, Old Problems 175
5.4.2 Channel Morphodynamics: Beyond Quantifying Flux 177
5.4.3 Future Opportunities and Challenges 178
5.5 Conclusions 179
Acknowledgements 180
References 180
Discussion 185
Chapter 6 Geomorphic Controls on Tracer Particle Dispersion in Gravel-Bed Rivers 189
6.1 Introduction 189
6.2 Bedload Estimates Using Tracers 190
6.3 Scales of Particle Motion 192
6.4 Types of Tracer Experiments and a Review of Results 192
6.5 Practical Relations for Travel Distance 195
6.6 Virtual Velocity 197
6.7 Burial Depth and Vertical Mixing 199
6.8 Depth of the Active Layer 201
6.9 Morphology 202
6.10 Bed Texture 206
6.11 Closing Remarks 207
Acknowledgments 208
References 209
Discussion 214
Chapter 7 Bedload Transport Measurements with Geophones, Hydrophones, and Underwater Microphones (Passive Acoustic Methods) 215
7.1 Introduction 215
7.1.1 The Need for Surrogate Measuring Techniques 215
7.1.2 Passive Acoustic Methods 216
7.2 Particle Impact Systems 217
7.2.1 Swiss Plate Geophone 217
7.2.2 Japanese Pipe Microphone (Hydrophone) 220
7.2.3 Other Impact Plate Systems 222
7.3 Underwater Microphones 225
7.4 Important Findings Related to System Calibration 226
7.4.1 Calibration for Total Mass Flux 226
7.4.2 Identification of Grain Size (Classes) 227
7.5 Some Operational Aspects to be Considered For Different Systems 230
7.6 Conclusions 230
Acknowledgement 231
References 231
Discussions 235
Chapter 8 Calibration of Acoustic Doppler Current Profiler Apparent Bedload Velocity to Bedload Transport Rate 239
8.1 Introduction 239
8.2 aDcp Apparent Bedload Velocity 240
8.2.1 Estimation 240
8.2.2 Sampling Volume 241
8.2.3 Errors 244
8.3 Previous Calibration Efforts 245
8.3.1 Fraser River 245
8.3.2 Missouri River 247
8.3.3 Trinity River 248
8.3.4 Assiniboine River 248
8.3.5 Saint Anthony Falls Laboratory 249
8.4 Rees River Survey: New Fractional Calibration Data 250
8.4.1 Study Site 250
8.4.2 Calibration Measurements 250
8.4.3 Analysis 250
8.5 Discussion 253
8.6 Conclusions 256
Notation 256
Acknowledgements 257
References 258
Discussion 261
Chapter 9 Modeling Surface–Subsurface Exchange of Heat and Nutrients 265
9.1 Introduction 265
9.2 Hyporheic Hydraulics 268
9.3 Hyporheic Residence Time 271
9.3.1 Pool–Riffle Morphology 271
9.3.2 Dune-Like Morphology 271
9.4 Damköhler Numbers 274
9.4.1 The Biogeochemical Damköhler Number 274
9.4.2 Thermal Damköhler Number 276
9.5 Role of Stream Morphology on Nitrous Oxide Emissions 277
9.6 Conclusions and Research Needs 279
Notation 280
Acknowledgments 281
Appendix 282
References 283
Discussion 289
Chapter 10 Ecological Effects of Flow Intermittence in Gravel-Bed Rivers 291
10.1 Introduction 291
10.2 Flow Intermittence in GBRs from a Hydrological Perspective 291
10.2.1 What is Flow Intermittence? 291
10.2.2 Intermittent Rivers: Importance and Distribution 293
10.2.3 Origins, Causes of Flow Intermittence, and Trends 295
10.3 Flow Intermittence in GBRs: an Ecohydrological Perspective 300
10.3.1 Flow Intermittence and Habitat Dynamics in GBRs at the Local Scale 300
10.3.2 Flow Intermittence and Habitat Dynamic in GBRs at the Reach Scale 303
10.3.3 Flow Intermittence and Habitat Dynamics in GBRs at the Catchment Scale 310
10.4 Intermittent GBRsas Coupled Aquatic–Terrestrial Disturbed Ecosystems 314
10.4.1 Disturbance Ecology and Intermittent GBRs 314
10.4.2 Aquatic and Terrestrial Communities, and their Interactions, in Intermittent GBRs 315
10.5 Flow Intermittence in GBRs: Research Needs and Open Questions 316
10.5.1 How Many, Where, How, and Why? 316
10.5.2 The Vertical Dimension: Surface- and Groundwater Interactions in Intermittent GBRs 317
10.5.3 Diversity Patterns and Community Dynamics at the Catchment Scale in Intermittent Rivers 317
10.5.4 Evolutionary Perspectives in Intermittent Rivers 317
10.5.5 Aquatic–Terrestrial Interactions in Intermittent GBRs 318
10.5.6 What are the Costs of Not Managing and Protecting Intermittent GBRs? 318
Acknowledgements 318
References 318
Chapter 11 Catastrophic Deposition of Gravel from Outbreak Floods 329
11.1 Introduction 329
11.2 Depositional Context 330
11.3 A Framework for Description of Megaflood Sedimentary Successions 331
11.4 Typical Sequences Within a Succession 332
11.4.1 Coarse Parallel-Bedded Units 333
11.4.2 Large-Scale Clinoforms 336
11.4.3 Horizontally Bedded Laminations 339
11.4.4 Ripple and Dune Cross-Lamination 340
11.4.5 Silt Beds 341
11.4.6 Debris Flow 344
11.5 Discussion 345
11.6 Conclusions 348
Acknowledgements 348
References 349
Discussion 355
Chapter 12 Linkage Between Sediment Transport and Supply in Mountain Rivers 359
12.1 Introduction 359
12.2 Sediment Supply to Mountain Rivers and its Influence on the Characteristics of the Sediment Available for Fluvial Tran... 360
12.2.1 Spatial Variations 360
12.2.2 Temporal Variations 363
12.3 Influence of Varying Sediment Availability on Sediment Transport and Export During Floods 366
12.3.1 Geomorphic Work as a Result of the Interplay Between Flood Magnitude and Sediment Supply 366
12.3.2 Grain Size and Sediment Mobility: the Boulder Issue 368
12.3.3 Sediment Transport During Extreme Flood Events 369
12.4 Concluding Remarks 375
Acknowledgement 375
References 375
Discussion 381
Chapter 13 Geomorphic Responses to Dam Removal in the United States – a Two-Decade Perspective 385
13.1 Introduction 385
13.2 Reservoir and Downstream Channel Responses to Dam Removal 387
13.2.1 Reservoir Erosion 387
13.2.2 Downstream Deposition 391
13.3 Factors Influencing Responses to Dam Removals 396
13.3.1 Dam Height and Removal Strategy 396
13.3.2 Relations Among Reservoir Sediment Volume, Rate of Sediment Release, and Background Sediment Flux 397
13.3.3 Reservoir-Sediment Grain Size 399
13.3.4 Breach and Post-Breach Hydrology 400
13.3.5 Downstream Valley Morphology 402
13.3.6 Watershed Geologic Setting and Geographic Context 402
13.4 Time Scales of Channel Responses to Dam Removals 403
13.5 Common Findings from Analyses of Responses to Dam Removals 405
Acknowledgments 407
References 407
Discussion 411
Chapter 14 Reservoir Sediment Flushing and Replenishment Below Dams: Insights from Japanese Case Studies 415
14.1 Introduction 415
14.2 Present State of Reservoir Sedimentation in Japan 416
14.2.1 Reservoir Storage Loss 416
14.2.2 Comprehensive Sediment Management in the Sediment Routing System 417
14.3 Selecting Suitable Sediment Management Options 418
14.3.1 Classification of Sediment Management Measures 418
14.3.2 Promotion Strategy of Reservoir Sedimentation Management 418
14.4 Sediment Flushing 420
14.4.1 Classification of Sediment Flushing 420
14.4.2 Case Study in the Kurobe River, Japan 423
14.4.3 Improvement of Sediment Flushing 428
14.4.4 Environmental Impacts 434
14.5 Sediment Replenishment 435
14.5.1 Definition and Objectives 435
14.5.2 Implementation of Sediment Replenishment 435
14.5.3 Environmental Effects and Monitoring 437
14.5.4 Case Studies in Japan 438
14.6 Conclusions 440
Acknowledgment 440
References 441
Chapter 15 Bedload Transport in Laboratory Rivers: The Erosion–Deposition Model 445
15.1 Introduction 445
15.2 The Erosion–Deposition Model 447
15.2.1 Laboratory Observations 447
15.2.2 Average Particle Velocity 450
15.2.3 Surface Concentration of Moving Particles 453
15.2.4 Bedload Transport Rate 454
15.3 Deposition Length and Bedforms 455
15.4 Spreading of a Plume of Tracers 457
15.5 Conclusions 460
Notation 460
Acknowledgements 461
References 461
Discussion 465
Chapter 16 Bedforms, Structures, Patches, and Sediment Supply in Gravel-Bed Rivers 469
16.1 Introduction 469
16.2 Bedload Transport, Sediment Supply, and Bed Mobility 469
16.2.1 Sediment Supply 470
16.2.2 Mobility of the Grain-Size Distribution 474
16.3 Bed Features in Gravel-Bed Rivers 476
16.3.1 Equal Mobility Regime 477
16.3.2 Selective Mobility Regime 478
16.3.3 Partial Mobility Regime 480
16.4 A Phase Diagram for Bed Features in a Gravel-Bedded River 486
16.5 Perspective and Conclusions 488
Acknowledgments 490
References 490
Discussion 494
Chapter 17 Linking Debris Flows and Landslides to Large Floods in Gravel-Bed Rivers 497
17.1 Introduction 497
17.2 Interactions Between Mass Wasting and Floods in Gravel-Bed Rivers 498
17.2.1 Changes in Flow Process Type 499
17.2.2 Increase in Sediment Transport 500
17.2.3 Channel Damming and Failures of Landslide Dams 500
17.2.4 Erosion and Delivery of Large Wood Debris 505
17.3 Approaches to Prediction 507
17.3.1 Temporal Scale 508
17.3.2 Spatial Scale 508
17.4 Discussion 515
17.5 Conclusions 517
Acknowledgements 517
References 517
Discussion 523
Chapter 18 Gravel Riverbed Processes Resulting from Large-Scale Landslides 527
18.1 Introduction 527
18.2 Case Study: Shoufeng River 528
18.2.1 Shoufeng River 528
18.2.2 Disaster History 528
18.2.3 Transformation of the Catchment 530
18.3 Case Study: Taimaili River 538
18.3.1 Background 538
18.3.2 Disaster History 539
18.3.3 Transformation of the Taimali River Catchment 539
18.4 Conclusion 542
Acknowledgements 543
References 543
Discussion 543
Reference 544
Chapter 19 Gravel-Bed River Management Focusing on Finer Sediment Behaviour 547
19.1 Introduction 547
19.2 Background Information 548
19.2.1 Grain-size Distribution of Sediment Supplied to Alluvial Rivers 549
19.2.2 Material m, s, and t for Classification of Riverbed Material 549
19.2.3 Classification of River Channels Based on Longitudinal Segment Types 549
19.2.4 Exchange Type and the Pass-Through Type for Grain-Size Group Movement 550
19.2.5 Class-A and Class-B River Systems 551
19.3 Vital Points to Advance Channel Management Strategy 552
19.3.1 Sensitivity of Flooding Probability to Riverbed Variation 552
19.3.2 Transition in Total Channel Capacity of Major Reaches of Japanese Rivers 553
19.3.3 Potential Impacts of Sediment Supply on Channel Capacity 555
19.3.4 Strategies for Channel Capacity Management 555
19.4 Role of Finer Sediment in the Expansion of Dense Vegetation Areas in Segment-1G Reaches 556
19.4.1 Deposition of a Top Fine-Sediment Layer as an Essential Process 556
19.4.2 Simulation of the Expansion and Extinction of Stable Vegetation Areas 559
19.4.3 Use of the Simulation Model for Channel Management Strategy 561
19.5 Floodplain Accretion by Finer Sediment Deposition and Resulting Channel Narrowing in Segment-2G Reaches 562
19.5.1 Channel Narrowing in the Sendai and the Powder Rivers 562
19.5.2 Mechanism of the Channel Narrowing by Fine Sediment Deposition 564
19.5.3 Development into Planar Two-Dimensional Calculation of Floodplain Accretion 568
19.6 Engineering Framework for Gravel-Bed River Management 570
Notation 571
Acknowledgements 572
References 573
Discussion 574
Chapter 20 Lahar Flow Disaster, Human Activities, and Risk Mitigation on Volcanic Rivers: Case Study of Rivers on Mount Merapi Slop... 579
20.1 Introduction 579
20.2 Riverbed Characteristics 582
20.3 Human Activities 584
20.3.1 Sand Mining in the Upper Pabelan River 587
20.3.2 Sand Mining in the Gendol River 587
20.3.3 Sand Mining in the Woro River 587
20.4 Sediment Management and Risk Mitigation 589
20.4.1 Damage Due to the 2010 Mount Merapi Eruption 589
20.4.2 The Human Dimension 590
20.4.3 Integrated Sediment Management 590
20.4.4 Minimizing Risk by Establishing Lahar-Flow Warning Criteria 591
20.5 Conclusions 594
Acknowledgements 594
References 595
Chapter 21 A Method for Estimating the Porosity of Sediment Mixtures and Application to a Bed-Porosity Variation Model 597
21.1 Introduction 597
21.2 Identification of Grain-Size Distribution 599
21.2.1 Classification 599
21.2.2 Identification 600
21.3 Relationship Between the Geometric Parameters of Grain-Size Distributions and Porosity 606
21.3.1 Particle-Packing Simulation 607
21.3.2 Measurement Method 607
21.3.3 Simulation and Measurement Results 609
21.4 An Algorithm for Estimating the Porosity 611
21.4.1 Input of Grain-Size Distribution Data 611
21.4.2 Identification and Classification 612
21.4.3 Obtaining the Geometric Parameters of Grain-Size Distribution 612
21.4.4 Estimating the Porosity 613
21.5 Application to Bed-Porosity Variation Model 613
21.5.1 Basic Equations 613
21.5.2 Conditions of Simulation 613
21.5.3 Results 614
21.6 Conclusions 616
Acknowledgements 616
References 616
Discussion 618
Chapter 22 Gravel Sorting and Variation of Riverbeds Containing Gravel, Sand, Silt and Clay 621
22.1 Introduction 621
22.2 Summary of Experiments 622
22.2.1 Experiment on a Bed with an Extremely Wide Range of Sediment Grain Size (Experimental Set 1) 622
22.2.2 Experiments on a Clay Bed (Experimental Set 2) 626
22.3 Vertical Sorting and Variation of the Riverbed with Extremely Wide Range of Sediment Sizes 627
22.4 Variation of a Clay Bed Caused by Sand or Gravel Transport Over It 631
22.5 Conclusions 636
Notation 637
Acknowledgement 638
References 638
Chapter 23 Modeling Stratigraphy-Based Gravel-Bed River Morphodynamics 639
23.1 Introduction 639
23.2 Model Formulation 642
23.2.1 Governing Equations for the Flow 643
23.2.2 Governing Equations for the Bed Material 643
23.2.3 Grain Size Specific Equations of Conservation of Bed Material in the Active Layer Model 644
23.2.4 Grain Size Specific Equations of Conservation of Bed Material in the Continuous Model 645
23.2.5 The Calculation Procedure 651
23.3 Application to a Case Inspired by the Trinity River, California, United States 651
23.3.1 The Active Layer Model Run 653
23.3.2 The Continuous Model Runs 655
23.4 Conclusions 660
Notation 661
Acknowledgments 663
References 663
Discussion 666
Chapter 24 Sediment Processes in Bedrock–Alluvial Rivers: Research Since 2010 and Modelling the Impact of Fluctuating Sediment Supp... 669
24.1 Introduction 669
24.2 Differences Between Sediment Processes in Alluvial and Bedrock–Alluvial Channels 669
24.3 Review of Sediment Processes in Bedrock–Alluvial Rivers Since 2010 670
24.3.1 Grain-Scale Dynamics 671
24.3.2 Sediment Cover 673
24.3.3 Morphology and Sediment Supply/Transport/Cover: Event Timescales 673
24.3.4 Morphology and Sediment Supply/Transport/Cover: Geological Timescales 674
24.3.5 Flow 675
24.4 Literature Review Findings and Cross-Cutting Themes 676
24.4.1 Saltation-Abrasion Model 676
24.4.2 Channel Evolution 676
24.4.3 Sediment Supply 677
24.5 Outstanding Research Questions 677
24.5.1 Flow Research Questions 677
24.5.2 Sediment Supply Research Questions 678
24.5.3 Sediment Cover Research Questions 679
24.5.4 Upscaling Research Questions 680
24.6 Implications for Modelling Sediment Processes in Bedrock–Alluvial Rivers 680
24.6.1 Appropriate Level of Process Representation 681
24.6.2 Stochastic Versus Deterministic Approaches 681
24.6.3 Constraining Boundary Conditions and Input Parameters 681
24.6.4 Developing Physical Models 681
24.7 An Application of a Numerical Model of Sediment Processes 681
24.7.1 Methods 682
24.7.2 Results 686
24.7.3 Discussion 691
24.8 Conclusions 693
Acknowledgements 694
References 694
Discussion 698
Chapter 25 Modelling Braided Channels Under Unsteady Flow and the Effect of Spatiotemporal Change of Vegetation on Bed and Channel ... 701
25.1 Introduction 701
25.2 Numerical Analysis Method 704
25.2.1 Framework of the Numerical Model 704
25.2.2 Hydraulic Conditions 710
25.3 Flume Experiments: Method and Hydraulic Conditions 715
25.4 Results and Discussion 715
25.4.1 Effects of Unsteady Characteristics of Water Supply on Bed and Channel Configuration 715
25.4.2 Effects of Vegetation Growth on Bed and Channel Configuration 719
25.4.3 Effects of Spatiotemporal Change of Vegetation on the Yoshino River 722
25.5 Conclusions 724
Notation 726
Acknowledgements 728
References 729
Discussion 731
Chapter 26 Modelling of Mixed-Sediment Morphodynamics in Gravel-Bed Rivers Using the Active-Layer Approach: Insights from Mathemati... 733
26.1 Introduction 733
26.2 The Saint-Venant–Hirano Model 735
26.2.1 Governing Equations 735
26.2.2 Closure Relations for Sediment Transport 737
26.3 Mathematical Analysis 738
26.3.1 The System in Matrix–Vector Form for a Two-Fraction Mixture 738
26.3.2 Analysis of Characteristics 739
26.3.3 Loss of Hyperbolic Character 742
26.3.4 Linearized Wave Dynamics 744
26.4 Assessment of Numerical Solutions 747
26.4.1 Numerical Modelling of Small-Amplitude Wave Dynamics 747
26.4.2 Streamwise and Vertical Sorting in a Flume Experiment 748
26.4.3 Failure of Numerical Solutions Under Elliptic Conditions 752
26.5 Conclusions and Research Perspectives 752
26.5.1 Restoration of Hyperbolicity 754
26.5.2 Improved Description of Vertical Sorting 754
26.5.3 Optimal Discretization of the Granulometric Curve 755
26.5.4 Two-Dimensional Morphodynamics: Bar Instability 755
Acknowledgements 755
References 756
Discussion 758
Chapter 27 Physical and Numerical Modelling of Large Wood and Vegetation in Rivers 759
27.1 Introduction 759
27.2 Physical Modelling of Vegetation 760
27.2.1 Flow–Vegetation Interaction 760
27.2.2 Characterization of Plant Growth and Uprooting 761
27.2.3 Reach-Scale Models of River Evolution: a Two-Way Interaction 763
27.3 Numerical Modelling of Riparian Vegetation 765
27.3.1 The Effect of Flow and Climate Change on Vegetation Dynamics 765
27.3.2 Effect on Bank Processes 766
27.3.3 Two-Dimensional Shallow-Water Models 767
27.4 Physical Modelling of Large Wood 769
27.4.1 Impact of Large Wood on Flooding 769
27.4.2 Impact of Large Wood on Habitat 769
27.4.3 Dynamics of Large Wood and River Morphology 771
27.5 Numerical Modelling of Instream Large Wood Transport 772
27.5.1 Modelling Large Wood Transport in Rivers Using a Computational Fluid-Dynamics Approach 772
27.5.2 Exploring Factors Controlling Large Wood Transport and Deposition 774
27.5.3 Potential Hazards Related to Instream Large Wood 774
27.6 Future Challenges 777
Acknowledgements 778
References 778
Chapter 28 Fluvial Gravels on Mars: Analysis and Implications 785
28.1 Introduction 785
28.2 First Observations of Fluvial Conglomerates on Mars 786
28.3 Some Fluvial Conglomerates on the Way to Mount Sharp 788
28.4 Estimates of Stream Velocity, Channel Discharge, and Gravel Mobility on Mars 789
28.4.1 Threshold Channel Concept 791
28.4.2 Hydraulic Geometry Applications 796
28.4.3 Analysis of Martian Gravel Conglomerates 800
28.5 Runoff Volume and Implications for Climate 803
28.6 Conclusions 805
Acknowledgments 806
References 806
Discussion 809
Index 815
Supplemental Images 829
EULA 845

Produkt-Details

• Erscheint lt. Verlag: 25.4.2017
• Sprache: englisch
• Themenwelt: Naturwissenschaften ► Geowissenschaften ► Hydrologie / Ozeanografie
• Themenwelt: Technik
• Schlagworte: earth sciences • ecologists • Fliessgewässer • Fluss • Flussbett • Fluvial Hydrology & Limnology • fluvial sedimentologists • geomorphologists • Geowissenschaften • Gravel-bed • gravel-bed ecology • gravel-bed instrumentation • Gravel-bed Rivers: Processes and Disaster • gravel-bed techniques • Groundwater & Hydrogeology • Grundwasser u. Hydrogeologie • Hydrological Sciences • Hydrologie • Hydrologie der Flüsse u. Binnengewässer • Integrated River Management • Kies • Morphodynamics • physical modeling • river bed ecology • River Ecology • river engineers • river flow • river managers • Sediment Supply • sediment transport theory
• ISBN-10: 1-118-97141-8 / 1118971418
• ISBN-13: 978-1-118-97141-3 / 9781118971413