Ecology of Sandy Shores (eBook)

Front cover 1
Title page 5
Copyright page 6
Table of contents 11
Acknowledgements 7
1: Introduction 15
2: The Physical Environment 19
2.1 Introduction 20
2.2 Sand 20
2.3 Waves 24
2.4 Other Drivers of Water Movement 29
2.5 Sand Transport 31
2.6 Interactions Among Beach Slope, Waves, Tides, and Sand 32
2.7 Beach Indices 33
2.8 Beach Types 34
2.9 Circulation Cells and Mixing 38
2.10 Embayments and Headlands 39
2.11 Swash Climate 40
2.12 Slope 42
2.13 Latitudinal Effects 43
2.14 Conclusions 43
3: The Interstitial Environment 45
3.1 Introduction 46
3.2 Characteristics of the System 46
3.3 Processes of Water Input 50
3.4 Water Filtration 54
3.5 Water Table Fluctuations 60
3.6 Interstitial Chemistry 63
3.7 The Interstitial Environment 67
3.8 Conclusions 68
4: Beach and Surf-zone Flora 69
4.1 Introduction 69
4.2 Benthic Microflora 69
4.3 Surf-zone Phytoplankton 71
4.4 Seagrasses 76
4.5 Conclusions 78
5: Sandy-beach Invertebrates 79
5.1 Introduction 79
5.2 Important Groups 80
5.3 Conclusions 104
6: Adaptations to Sandy-beach Life 105
6.1 Introduction 105
6.2 Locomotion 106
6.3 Rhythms of Activity 113
6.4 Sensory Responses and Orientation 119
6.5 Choice of Habitat 122
6.6 Nutrition 125
6.7 Respiration 127
6.8 Environmental Tolerances 130
6.9 Reproduction 133
6.10 Aggregations and Gregariousness 134
6.11 Avoidance of Predators 135
6.12 Phenotypic Plasticity 135
6.13 Conclusions 136
7: Benthic Macrofauna Communities 139
7.1 Introduction 139
7.2 Sampling 140
7.3 Taxonomic Composition 142
7.4 Macroscale Patterns 143
7.5 Mesoscale Patterns 154
7.6 Microscale Patterns 164
7.7 Trophic Relations 173
7.8 Conclusions 175
8: Benthic Macrofauna Populations 177
8.1 Introduction 177
8.2 Macroscale Patterns 178
8.3 Mesoscale Patterns 182
8.4 Microscale Patterns 187
8.5 Invertebrate Fisheries 189
8.6 Conclusions 193
9: Interstitial Ecology 195
9.1 Introduction 195
9.2 Interstitial Climate 196
9.3 Sampling 197
9.4 Interstitial Biota 197
9.5 Distribution of Interstitial Fauna 200
9.6 Temporal Changes 202
9.7 Meiofaunal Communities 203
9.8 Trophic Relationships 206
9.9 Biological Interactions 207
9.10 Meiofauna and Pollution 209
9.11 Conclusions 209
10: Surf-zone Fauna 211
10.1 Introduction 211
10.2 Zooplankton 211
10.3 Fishes 217
10.4 Other Groups 226
10.5 Conclusions 226
11: Turtles and Terrestrial Vertebrates 229
11.1 Introduction 229
11.2 Turtles 229
11.3 Birds 232
11.4 Conclusions 236
12: Energetics and Nutrient Cycling 237
12.1 Introduction 237
12.2 Food Sources 238
12.3 Macroscopic Food Chains 240
12.4 Interstitial Food Chains 247
12.5 The Microbial Loop in Surf Waters 250
12.6 Energy Flow in Beach and Surf-zone Ecosystems 252
12.7 Case Study: Sandy Beaches of the Eastern Cape 254
12.8 Nutrient Cycling 258
12.9 Conclusions 262
13: Coastal Dune Ecosystems and Dune/Beach Interactions 265
13.1 Introduction 265
13.2 The Physical Environment 266
13.3 Coastal Dune Formation by Vegetation 267
13.4 Dune Types 268
13.5 Edaphic Features 271
13.6 Water 272
13.7 The Gradient Across Coastal Dunefields 273
13.8 Dune Vegetation 273
13.9 The Fauna 275
13.10 Food Chains 279
13.11 Dune/Beach Exchanges 281
13.12 A Case Study of Dune/Beach Exchanges 282
13.13 Conclusions 285
14: Human Impacts 287
14.1 Introduction 288
14.2 Pollution 288
14.3 Recreational Activities 298
14.4 Global Warming 302
14.5 Direct Human Pressure 304
14.6 Altering the Landscape 305
14.7 Natural Impacts 311
14.8 Human Influence on the Evolution of Beaches 311
14.9 Conclusions 314
15: Coastal Zone Management 317
15.1 Introduction 317
15.2 The Littoral Active Zone 318
15.3 Summary of Threats 320
15.4 Principles of Coastal Zone Management 321
15.5 Management, Planning, and Implementation 330
15.6 Case Studies 331
15.7 Conservation 336
15.8 Conclusions 337
16: Glossary 339
17: References 343
18: Appendices 367
Appendix A: Measures of Beach Type 367
Appendix B: The Chemical Environment of Sediments 369
Index 371