Landform Dynamics and Evolution in Romania (eBook)

Preface 6
Contents 9
Contributors 13
1 Introduction 16
Abstract 16
The Framework of Current Approaches in Geomorphology 16
Temporal and Spatial Scales of the Geomorphological Processes Herein Approached 18
Landmarks in the Development of Modern Romanian Geomorphology 20
References 25
Background of Landform Evolution 27
2 Tectonics and Exhumation of Romanian Carpathians: Inferences from Kinematic and Thermochronological Studies 28
Abstract 28
Introduction 29
Main Tectonic Units of the Romanian Carpathians 31
The Relationship Between Tectonics and Exhumation in the Romanian Carpathian Mountains 37
Collision of the East Carpathians 38
Out-of-Sequence Thin- Versus Thick-Skinned Accretion in the SE Carpathians 41
Nappe Stacking, Orogen Parallel Extension and Transcurrent Movements in the South Carpathians 42
The Orogenic Evolution and Subsequent Stability of the Apuseni Mountains 45
Dynamic Topography in the Transylvanian Basin 46
Mechanisms Driving the Miocene–Quaternary Evolution of the Carpathians Foredeep and Foreland Platforms 48
The Extension and Inversion of the Pannonian Basin 50
Mechanics of Continental Collision and Large-Scale Evolution of Topography 52
Mechanics of Collision in the Romanian Carpathians 53
Inferences for the Tectonic Age of Romanian Carpathians Topography 56
Conclusions 58
Acknowledgments 59
References 59
3 Climate Evolution During the Late Glacial and the Holocene 70
Abstract 70
Introduction 71
Sources of Palaeoclimate Data 72
Speleothems 72
Peat bogs and Lakes 73
Tree Rings 73
Guano 74
Past Climate Reconstructions 74
Late Glacial 74
The Holocene 76
The Last 1000 Years 77
Acknowledgements 77
References 77
4 The Evolution of Vegetation from the Last Glacial Maximum Until the Present 80
Abstract 80
Introduction 81
Palaeoecological Indicators in the Sedimentary Archives 81
Vegetation Responses from LGM to Early Holocene Abrupt Climatic Change 83
General Trends 83
Ecosystem Responses to Repeated Climatic Shifts of the Lateglacial 87
Patterns in the Main Tree Taxa Dynamics During the Holocene 89
The Influence of Human Impact on the Vegetation 92
Acknowledgements 93
References 94
Glacial and Periglacial Landforms 97
5 Deglaciation History of High Massifs from the Romanian Carpathians: Towards an Integrated View 98
Abstract 98
Introduction 99
Regional Settings 100
Deglaciation Chronology of the Romanian Carpathians 102
Retezat Massif 103
Parâng Massif 106
F?g?ra? Massif 108
Rodnei Massif 109
Towards an Integrated View of the Deglaciation History of the Romanian Carpathians 112
Glaciers Extent During the Local Last Glacial Maximum (36?, 26–19 Ka) 112
Glaciers Still-Stands and Readvances During the Cold Phases of the Late Glacial (19–13 Ka Period) 115
Younger Dryas: From Glaciers to Rock Glaciers (12.9–11.6 Ka) 117
Concluding Remarks and Open Questions 122
Acknowledgements 123
References 123
6 Spatial Distribution and Main Characteristics of Alpine Permafrost from Southern Carpathians, Romania 128
Abstract 128
Introduction 129
Regional Settings 130
The Key Factors for Permafrost Development 132
General Presentation 132
Grain Size of Debris Deposits—The Key Factor for Permafrost Development in Marginal Periglacial Environment 134
Ground Overcooling Processes in Southern Carpathians 136
Permafrost Distribution Patterns in the Southern Carpathians 140
Background 140
Rock Glaciers (RG) Permafrost 141
Talus Slope Permafrost 146
Rockwall Permafrost Probability 148
Internal Structure and Characteristics of Permafrost 149
Conclusions 151
Acknowledgments 153
References 153
7 Present-Day Periglacial Processes in the Alpine Zone 158
Abstract 158
Background 159
Romanian Carpathians Periglacial Phenomena 160
Periglacial Deposits and Post-glacial Denudation Rates 161
Frost Heaving 165
Solifluction 168
Ploughing Blocks 173
Frost Creep and Other Periglacial Processes 176
Creep of Permafrost 177
Environmental Control on the Periglacial Phenomena 178
Concluding Remarks: Towards Improving the Understanding of the Present-Day Periglacial Processes in the Romanian Carpathians 181
Acknowledgements 182
References 182
8 Thermal Weathering and Distribution of Mountain Rockwalls 188
Abstract 188
Background 189
Models and Concepts in Thermal Weathering 190
Topography and Ground Cover Control on Freeze-Thaw Weathering 192
Freeze-Thaw Regime of Mountain Rockwalls and Magnitude Assessment 196
Rockwalls Distribution and Thermal Weathering Potential 200
Conclusions 204
Acknowledgments 205
References 205
9 Glacial Cirques in the Romanian Carpathians and Their Climatic Implications 208
Abstract 208
Carpathian Glaciation: Background 208
Distribution of Cirques 209
Ranges Apparently Lacking Cirques 211
Altitude 212
Aspect and Wind 213
Size 215
Shape 217
Classification 219
Geology 221
Discussion: Origins 222
Conclusions 222
References 223
10 Geomorphosites Assessments of the Glacial and Periglacial Landforms from Southern Carpathians 225
Abstract 225
Introduction 226
The Inventory of the Geomorphosites 227
The Temporal–Functional Criterion 228
The Genetic Criterion 228
The Tourism Relevance Criterion 228
The Surface Criterion 229
Evaluating Geomorphosites 233
Evaluation Using Pralong (2005) Method 235
Coratza and Giusti (2005) Method 240
Bruschi and Cendrero (2005) Method 241
Serrano and Gonzalez-Trueba (2005) Method 243
Reynard et al. (2007) Method 244
Pereira et al. (2007) Method 246
Zouros (2007) Method 248
Com?nescu et al. (2012) Method 249
Discussions 250
Conclusions 254
References 254
Hillslope Evolution by Mass Movement Processes 257
11 The Systematic of Landslide Processes in the Conditions of Romania’s Relief 258
Abstract 258
A Short History 259
1910–1960: Pioneering and Fundaments 259
1960–1990: Forms, Processes, and Remediation Suggestions 261
1990–2000: New Horizons 264
Landslide Typology in Romania: An Updated Picture 264
Slides 265
Flows 266
Falls 267
Spreads 267
Topples 268
Creep 269
Compound/Complex 270
Conclusions 271
References 275
12 Landslide Type and Pattern in Moldavian Plateau, NE Romania 279
Abstract 279
Introduction 279
Study Area 280
The General Framework 280
Landslide Causal Factors 283
Preconditioning Factors 283
Preparatory Factors 286
Triggering Factors 287
Materials and Methods 288
Data Acquisition and Preparation 288
Landslide Inventory 288
Statistical Analysis 289
Results and Discussions 289
Landslide Types 289
Rotational Slides (Slumps) 293
Translational Slides 294
Earth Flows 295
Lateral Spreads 295
Complex Landslides 297
Spatial and Morphometric Patterns of the Landslides 297
General Remarks 306
Conclusions 307
Acknowledgments 308
References 308
13 Landslide Types and Spatial Pattern in the Subcarpathian Area 313
Abstract 313
Introduction 313
Study Area 314
Landslides Typology and Spatial Patterns 316
Predisposing Factors 316
Preparatory and Triggering Factors 318
Trigger: Precipitation 318
Trigger: Earthquakes 319
Landslide Typology in the Subcarpathians 322
Slides 322
Flows 323
Falls 324
Complex 325
Landslide Spatial Pattern in the Subcarpathians 326
Conclusions 329
References 329
14 Debris Flows in C?limani Mountains and Lotrului Valley 334
Abstract 334
Introduction 335
DF Activity and Resulting Landforms 336
Geomorphic Evidences Used to Recognize DF Deposits 336
Sedimentologic Evidence Used to Recognize DF Deposits 337
DF Assessment in Romanian Carpathians 337
Inventory of DF Affected Areas in C?limani Mountains and Lotrului Valley 338
Causative Factors Explaining Spatial Distribution and DF Occurrence 340
Geological, Geomorphological and Topographic Factors 340
Climatic Factors 343
Anthropic Factors 343
Reconstructing Past Debris Flow Activity 345
DF Hazard Management 348
Concluding Remarks 349
References 350
Soil Erosion 352
15 Sheet and Rill Erosion 353
Abstract 353
Introduction 353
Description of Experimental Sites and Working Methods 355
Analysis of the Relation Between Precipitation, Surface Runoff and Soil Erosion 359
Evaluation of Soil Conservation Measures Effectiveness in the Conditions of Extreme Rainfall Events 363
Assessment of Soil Water Storage in Anti-erosion Areas Equipped with Forest Belts 366
Estimating Surface Erosion in Small Catchments by Conventional and Unconventional Methods 368
Discussions and General Conclusions 371
Acknowledgments 374
References 374
16 Gully Erosion 376
Abstract 376
Introduction 377
Gully Typology 378
Gully Distribution 378
Case Study Investigations on Forms and Processes in a Gully System 383
Gully Advancement Rates 391
Gully Advancement Time 394
Gully Erosion Prevention and Control 397
Conclusions 398
Acknowledgments 399
References 399
17 Soil Erosion Modelling 402
Abstract 402
Introduction 403
Erosion Models Applied in Romania 404
USLE/RUSLE Versus ROMSEM 412
Example of ROMSEM Application 422
Conclusions 424
References 425
Rivers 429
18 Geomorphological Evolution and Longitudinal Profiles 430
Abstract 430
Longitudinal Profiles and the Knick-Points and Knickzones Approach 431
Tectonic and Lithologic Control on the Evolution of the Drainage Network 432
Longitudinal Profiles Concavity Related to River Age and Channel Bed Material Grain Size 439
Conclusions 444
Acknowledgments 444
References 444
19 River Behavior During Pleniglacial–Late Glacial 446
Abstract 446
Introduction 447
Regional Synthesis on Pleniglacial–Late Glacial Fluvial History 449
Western Romanian Plain (Great Hungarian Plain) 449
Transylvanian Depression 455
Discussion 457
SE Carpathians (Curvature Carpathians) 458
Moldavian Plateau 460
Romanian Plain, the Lower Course of Danube River 461
Discussion 464
The Role of Natural Controls on Pleniglacial–Late Glacial Fluvial Adjustments 465
Conclusions 468
Acknowledgments 469
References 469
20 Fluvial Activity During the Holocene 472
Abstract 472
Introduction 473
Fluvial Processes and Mechanisms 475
The Late Glacial–Holocene Transition 475
The Holocene 478
The Holocene Fluvial Sedimentological and Morphological Features 483
Conclusion 487
Acknowledgments 489
References 489
21 Styles of Channel Adjustments in the Last 150 Years 492
Abstract 492
Introduction 493
Reconstructing Fluvial Changes in Terms of Channel Planform Adjustments 494
Channel Bed-Level Adjustments During the Past 50 Years 500
Spatial Trends of Channel Bed-Level Adjustments 501
Decadal Trends of Channel Bed Level Adjustments 505
Climate Versus Anthropogenic in the Evolution of River Channels 507
Comparative Approach to the Evolution of Romanian River Channels and Channels from Other European Regions 514
Acknowledgments 517
References 518
Black Sea Coast and Danube Delta 522
22 The Evolution of Danube Delta After Black Sea Reconnection to World Ocean 523
Abstract 523
Introduction 524
A Short History of the Theories Concerning Danube Delta Genesis and Evolution 526
The Fluvial Delta Evolution 528
The Initial Spit (6.7/6.5–5.8 ka) 530
Morphological Evidences 532
Early Delta Stage of Coastal Progradation into Danube Bay (8/7.5–5.5 ka) 533
Late Delta Stage of Fluvial Aggradation (5.5 ka—Present) 534
The Maritime Delta Evolution 536
Old Sf. Gheorghe Lobe (SG1: 6/5.5–3.5 ka) 538
Sulina Lobe (3.5–2.0/1.35 ka) 540
Dunav?? Lobes (2.6–2 ka / 2–1.3 ka) 542
Modern Sf. Gheorghe Lobe (2.1/1.4 ka—Present) 543
Modern Chilia Lobe (0.9 ka—Present) 545
Beach Ridge Plains 547
Conclusions 548
Acknowledgments 549
References 549
23 Danube Delta Coastline Evolution (1856–2010) 552
Abstract 552
Introduction 553
Coastline Evolution in the past 150 Years 555
Climate Variability Imprint on Multi-decadal Shoreline Dynamics 558
Conclusions 562
Acknowledgements 563
References 563
24 Soft Cliffs Retreat Under the Shadow of Three Ports on the Southern Romanian Coast 566
Abstract 566
Introduction 567
General Background 567
Morphodynamics Hidden in Maps 570
Morphology of the Coast 571
Morphodynamics Under Anthropogenic Footprint 575
Conclusions 578
References 578
25 Foredunes Dynamics on the Danube Delta Coast 581
Abstract 581
Introduction 581
Regional Setting 583
Foredune Morphology Along the Deltaic Coast 586
Foredunes Developed on Barrier Islands and Spits 586
Musura Island 587
Sacalin Spit 588
Fordunes Developed on Beach Ridge Plains 589
Sulina Beach 589
S?r?turile Ridge Plain 590
Foredune Evolution on Danube Delta Coast 596
The Erosive Beach (Northern Sector: PN—OGA53) 597
The Stable Beach (Central Sector: OGA 53—Parid) 597
Accretionary Beach (the Southern Sector: Parid—Cape Buival) 600
Sacalin Barrier Island 602
Conclusions 603
Acknowledgments 604
References 604
26 Evolution and Morphodynamics of Danube Delta Shoreface 607
Abstract 607
Introduction 608
Present-Day Danube Delta Shoreface Characteristics 610
Long-Term Shoreface Evolution (the last 150 Years) 615
Inter-annual Shoreface Morphodynamics and Sandbar Behaviour 619
Conclusions 623
Acknowledgements 624
References 624
Dynamics of the Sediment System 627
27 Sediment Sources and Delivery 628
Abstract 628
Introduction 629
Sediment Sources in Relation with Sediment–Yielding Processes 632
Sheet Erosion as Sediment Sources 633
Gully Erosion Processes as Sediment Sources 636
Mass Movement Processes as Sediment Sources 637
Fluvial Processes as Sediment Sources 639
Sediment Sources According to Area of Origin 640
Sediment Yield 643
Sediment Delivery Ratio (SDR) 645
Conclusions 649
Acknowledgements 650
References 650
28 River Channel Sediments 654
Abstract 654
Introduction 654
East-Carpathian Rivers’ Sediment Sources and Transfer Rates 656
Granulometric Spectrum of Rivers from Siret and Prut Drainage Basins 658
Spatial Pattern of Riverbed Deposit Bimodality 661
Morphometric Variability of Riverbed Material 669
Petrographic Variability of Gravel 672
Discussions and Conclusions 673
Acknowledgements 674
References 674
29 The Lower Danube Loess, New Age Constraints from Luminescence Dating, Magnetic Proxies and Isochronous Tephra Markers 677
Abstract 677
Introduction 678
The Dating Approach of the Romanian Loess-Palaeosols Sequences 680
Magnetic Susceptibility and Magnetic Time Depth Model 682
New Constraints from Optically Stimulated Luminescence (OSL) Dating 684
The Method 684
OSL Chronologies on Romanian Loess 685
Point Age Control—The Campanian Ignimbrite/Y5 Tephra 688
Concluding Remarks 691
Acknowledgments 692
References 692
30 Lakes, Lacustrine Sediments, and Palaeoenvironmental Reconstructions 696
Abstract 696
Introduction 697
Romanian Lakes 697
Lake Genesis 698
An Overview on Lacustrine Sites Investigated to Date 699
Site Elevation and Latitudinal Location 699
Site Type and Origin 700
Sediment Thickness and Ages 714
Lacustrine/Peat Bog Sedimentation Rates 714
An Integrated Late Pleniglacial–Holocene Palaeoenvironmental Perspective Based on Geochemical and Biological Lake Sediment Proxies 716
Sensitivity to Climatic Signals 717
Human Impact 725
Conclusions 726
Acknowledgments 726
References 727
Geomorphologic Hazards 732
31 Snow Avalanche Activity in Southern Carpathians (Romanian Carpathians) 733
Abstract 733
Introduction 734
Study Area 736
A Review of Snow Avalanches Research in the F?g?ra? Massif and the Bucegi Mountains 736
Formation and Motion of Snow Avalanches 736
Snow Avalanche Accidents 737
Site Selection and Location 738
Tree Ring Analysis of Snow Avalanches in Southern Carpathians 741
Impact of Snow Avalanche Activity 741
Snow Avalanche Chronology 744
Age of Sampled Trees 744
Tree Ring Analysis of Snow Avalanches 745
Magnitude and Frequency of Snow Avalanches 748
Snow Avalanche Synchronicity 751
Snow Avalanche Activity and Climate Relationships 751
Final Remarks 753
References 755
32 Mass Movements 760
Abstract 760
Mass Movements Assessment: From Process to Risk 761
Data and Methodological Approaches 766
Necessary Data for Landslide Inventory 766
Data and Methodologies Used in Landslide Susceptibility Assessment 767
Data and Methodologies Used in Landslide Hazard Estimation 768
Data and Methodologies Used in Landslide Risk Analysis 770
Landslide Inventory and Its Place Within Risk Analysis 771
Landslide Inventory: Results Within Large Homogeneous Morphostructural Units 771
Landslide Inventory: Results at a Catchment Level 773
Landslide Susceptibility Assessment 775
Expert Knowledge and Statistical Analysis in Landslide Susceptibility Assessment: A Case Study in the Curvature Subcarpathians 775
Landslide Susceptibility Assessment in Tableland Regions: Case Studies from the Transylvanian and Moldavian Plateaus 777
Landslide Susceptibility Assessment in Large Drainage Basins: The Case Study of the Olte? River Basin 778
Rockfall Susceptibility Estimation in the Carpathian Mountains 781
Landslide Hazard Assessment 782
Triggering Factors and Thresholds 782
Triggering Thresholds and Recurrence Intervals 783
Landslide Risk Analysis 796
Exposure, Vulnerability, and Risk Assessment to Landslides 796
Exposure 797
Vulnerability 798
Risk 799
Uncertainties Within Landslide Susceptibility–Risk Studies 801
Dealing with Uncertainty in Susceptibility and Hazard Assessments 801
Dealing with Uncertainty in Vulnerability and Risk Assessment 803
Conclusions 804
Acknowledgments 806
References 806
33 Floods and Flash-Floods Related to River Channel Dynamics 816
Abstract 816
Introduction 817
Characteristics of the Floods in Romania and Hydrogeomorphological Interrelations 818
The Origin, Frequency and Magnitude of Floods in Romania 818
Hydrogeomorphological Inter-conditionings 820
River Channels Particularities—Control Factors of Floods and Flash-Floods 822
Case Studies on the Relation Between River Channel Dynamics and Floods 824
Rivers from the Region of the External Curvature (Carpathians, Subcarpathians, Plain) 824
Rivers from the Central Sector of the Romanian Plain 826
Transylvanian Depression 828
Rivers from the Banat Plain 829
The Danube River on Romanian Territory 830
Flash-Floods and Their Morphodynamic Role 834
Conclusions 835
References 835
34 Storm Climate and Morphological Imprints on the Danube Delta Coast 840
Abstract 840
Introduction 841
Regional Setting 842
Methods 843
Results 846
Seasonality and Multidecadal Variability 846
Links with Large-Scale Teleconnection Patterns 849
Storm Impact on the Coast 851
Long-Term Imprints on Morphology 856
Conclusions 856
Acknowledgments 857
References 857