Marine Biology

Roberto Danovaro is a Professor of Marine Ecology at the Polytechnic University of Marche, Italy. He is a Member of the EU Academy of Science and of the Academia Europaea (London). Editor in Chief of Marine Ecology (Wiley) and Chemistry & Ecology (T&F). Coordinator of several EU and international projects. Author of >500 scientific articles and 3 books, his research interests are focused on marine biodiversity and ecosystem functioning, and on the impact of climate change on deep-sea ecosystems. According to ExpertScape he has been the most influential World Scientist in the Category “Ocean and Seas” for the decade 2010-2020. Paul Snelgrove is a Professor of Ocean Sciences and Biology at Memorial University of Newfoundland in Canada. From 2008-2021 he led the Natural Sciences and Engineering Research Council of Canada (NSERC) Canadian Healthy Oceans Network, a national research network that supported sustainable oceans. He currently plays the role of Associate Scientific Director of The Ocean Frontier Institute, which gathers researchers in Atlantic Canada and beyond to advance safe and sustainable ocean objectives. He has published >150 papers and book chapters as well as one book. His research focuses on biodiversity, functioning, and conservation of seafloor ecosystems.

Acknowledgments xvii

Preface xix

About the Companion Website xxi

Part I The Ocean Domain: Introduction to Planet Ocean 1

1 The Life Aquatic 3

1.1 Introduction 3

1.2 Comparison Between Sea and Land 3

1.3 Fractal Complexity of Marine and Terrestrial Ecosystems 6

2 The Seabed 13

2.1 Ocean Basins 13

2.2 Ocean Bottom: A (Mostly) Static Habitat of Ocean Life 15

2.3 Characteristics of Sediments 20

2.4 Boundary Layers and Their Characteristics 20

2.5 Sediment Movement 23

2.6 Characteristics of Hard Substrata 26

2.7 Characteristics of Soft Sediments 26

3 The Water Column 29

3.1 Properties and Characteristics of Seawater 29

3.2 An Ocean In Motion 44

Part II Life in Seas and Oceans: Fundamentals of Marine Biology 53

4 General Adaptations in Marine Organisms I: From the Ocean Surface to the Seabed 55

4.1 Adaptations to Temperature 55

4.2 Adaptations to Low Oxygen Concentrations 60

4.3 Adaptation to Salinity 64

4.4 Adaptation to Pressure 68

4.5 Adaptations to Light 69

4.6 Adaptations to Nutrients 73

4.7 Electrical Conductivity Adaptations 74

4.8 Ectocrine Adaptations 74

4.9 Adaptations to Produce Sound and Communicate in Water 74

5 Adaptations in Marine Organisms II: Life in a Fluid Habitat 79

5.1 Adaptions to Life in the Water Column 79

6 Adaptations in Marine Organisms III: Benthic Biota between a Rock and a Soft Place 91

6.1 Adaptations to Life on the Seafloor 91

6.2 Support and Protection Structures 91

6.3 Adaptation to Waves and Energy 94

6.4 Feeding and Nutrition 95

6.5 Adaptation to Aerial Exposure 98

6.6 Adaptation to Extreme Temperatures and Potentially Toxic Chemicals 98

Part IIB Life in Seas and Oceans: Fundamentals of Marine Biology 101

7 Marine Biodiversity 103

7.1 Introduction 103

7.2 Origin and Evolution of Marine Life 103

7.3 Mechanisms of Marine Speciation 107

7.4 Quantifying Marine Organism Biodiversity 113

8 Biodiversity Patterns 125

8.1 Broad-Scale Biodiversity Patterns 125

8.2 Processes Controlling the Distribution of Marine Biodiversity 125

8.3 Marine Biogeography 128

8.4 Theories on Evolution and Maintenance of Biodiversity: The Deep-Sea as Examplar 136

9 Biodiversity of the Benthos 141

9.1 Introduction: Benthos and Plankton 141

9.2 Benthic Biota 141

9.3 Classification of Benthos Based on Size 144

Part IIC Life in Seas and Oceans: Fundamentals of Marine Biology 157

10 Ecology of Benthos 159

10.1 Ecology of the Benthos: From Microbes to Megafauna 159

10.2 Trophic Groups: Classification of Benthos Based on Diet 164

10.3 Comparison Between Hard and Soft Bottom Benthos 165

10.4 Ecology of Benthos Inhabiting Soft Bottoms 167

10.5 Changes in Benthos in Space and Time 170

10.6 Organization of Benthic Assemblages 171

10.7 Zonation of Benthic Organisms 172

11 Biodiversity of the Plankton 179

11.1 Introduction to the Plankton 179

11.2 Planktonic Organisms 180

11.3 Planktonic Classification Based on Water Column Distributions 181

11.4 Plankton Classification Based on Life Cycles 182

11.5 Plankton Size Classes 184

11.6 Abundance Comparisons Among Different Planktonic Components 197

12 Ecology of the Plankton 201

12.1 Plankton Distribution 201

12.2 Ecology of Plankton 208

12.3 How Many Phytoplankton Species Coexist in a Volume of Water? “Homage to Santa Rosalia” 211

12.4 Zooplankton Nutritional Mode 211

Part IID Life in Seas and Oceans: Fundamentals of Marine Biology 215

13 Biodiversity of the Nekton 217

13.1 Species Contributing to the Nekton 217

13.2 Main Organisms and Characteristics of Nekton 218

13.3 Fishes 218

13.4 Marine Mammals 224

13.5 Cephalopods 227

13.6 Reptiles – The “Land-based” Marine Species 228

13.7 Seabirds 228

13.7 Patterns of Biodiversity in Nekton 229

14 Ecology of the Nekton 233

14.1 Introduction 233

14.2 Fishes and Formation of Fish Shoals 233

14.3 Ecology of Chondrichthyes 235

14.4 Sharks at Risk of Extinction from Indiscriminate Hunting 236

14.5 Ecology of Cephalopods 236

14.6 Marine Reptile Ecology 239

14.7 Ecology of Seabirds 241

14.8 Ecology of Marine Mammals 242

14.9 Great Migrations of Nekton 247

14.10 Role of Top Predators in Food Webs 255

15 Life Cycles and Larval Ecology 261

15.1 Life Cycles and Reproduction 261

15.2 Larval Ecology 264

15.3 Life History Strategies 267

15.4 Supply Side Ecology 270

15.5 Forms of Resistance and Benthic-pelagic Coupling 270

Part III Comparative Marine Ecology: Habitat Types, Their Biodiversity, and Their Functioning 275

16 Ecosystem Functioning I: Primary and Secondary Production 277

16.1 Introduction 277

16.2 Primary Production 277

16.3 Chemosynthetic Primary Production in the Ocean 278

16.4 Photosynthetic Primary Production 280

16.5 Secondary Production 287

16.6 Respiration 290

17 Ecosystem Functioning II: Organic Matter Recycling 293

17.1 Introduction – Extra-Specific Processes 293

17.2 Organic Matter and Detritus in the Ocean 293

17.3 Dissolved Organic Matter in the Ocean (DOM) 299

17.4 Pelagic-Benthic Coupling 300

17.5 Consequences of Organic Matter Export to the Seabed 307

18 Interspecific Interactions and Trophic Cascades 313

18.1 Biodiversity and Ecosystem Functioning 313

18.2 Facilitation and Cooperation – Positive Interactions 315

18.3 Symbiosis 319

18.4 Complex Biotic Interactions: Trophic Networks and Cascades 323

18.5 Keystone Species 333

18.6 Trophic Cascades 333

Part IIIB Comparative Marine Ecology: Habitat Types, Their Biodiversity, and Their Functioning 341

19 Interspecific Interactions II: Negative Interactions 343

19.1 Predation 343

19.2 Methods to Escape Predation 348

19.3 Competition 349

19.4 Parasitism 351

19.5 Diseases of Marine Organisms 354

20 Intertidal Ecosystems and Lagoons 359

20.1 Rocky Intertidal Habitats 359

20.2 Transitional Environments Between Land and Ocean 372

20.3 Mangroves 380

20.4 Salt Marshes 385

20.5 Summary 388

21 Subtidal Hard Substrata Ecosystems 391

21.1 Introduction 391

21.2 Subtidal Distributions 391

21.3 Kelp Forests 394

21.4 Coral Reefs 399

21.5 Coralligenous Habitats 418

21.6 Rhodolith Beds (Maërl) 422

21.7 Underwater Caves 423

21.8 Summary 429

Part IIIC Comparative Marine Ecology: Habitat Types, Their Biodiversity, and Their Functioning 431

22 Estuarine, Seagrass, and Sedimentary Habitats 433

22.1 Estuaries 433

22.2 Seagrass Beds 438

22.3 Sedimentary Habitats 446

23 Polar Ecosystems 455

23.1 Biogeography and Characteristics 457

23.2 Biodiversity 460

23.3 Biodiversity Within Sea Ice 460

23.4 Pelagic Biodiversity 462

23.5 Fishes 464

23.6 Marine Mammals 465

23.7 Benthic Biodiversity 465

23.8 Food Webs and Functioning 466

23.9 Antarctica 467

23.10 Summary 483

24 Neritic Aquatic Ecosystems 485

24.1 Introduction 485

24.2 Zonation, Extent, and Distribution 485

24.3 Biogeography and Characteristics 485

24.4 Biological Characteristics 487

24.5 Ecosystem Functioning in the Neritic Zone 490

24.6 Fisheries Production 492

24.7 Factors Influencing Functioning of Neritic Systems 493

24.8 Summary 497

Part IIID Comparative Marine Ecology: Habitat Types, Their Biodiversity, and Their Functioning 499

25 Deep-Sea Ecosystems along Continental Margins 501

25.1 Introduction to the Deep Sea 501

25.2 Deep-Sea Biodiversity 508

25.3 Deep-Sea Habitats 511

25.4 Submarine Canyons 512

25.5 Deep-Water Corals 515

25.6 Cold Seep (Hydrocarbon-Based) Ecosystems 517

25.7 Cold Seep Biodiversity and Symbiotic Organisms 518

25.8 Hypoxic and Anoxic Systems (Dead Zones) 522

25.9 Oxygen Minimum Zones, OMZs 522

25.10 Summary 526

26 Deep Ocean Basins 531

26.1 Introduction 531

26.2 Abyssal Plains 531

26.3 Abyssal Biodiversity and Adaptations 531

26.4 Abyssal Gigantism and Dwarfism 533

26.5 Functioning of Abyssal Systems 535

26.6 Deep-Sea Hydrothermal Vents 541

26.7 Whale Carcasses 551

26.8 Affinities Between Vent and Seep Communities 554

26.9 Anoxic Basins 554

26.10 Ocean Trenches 556

26.11 Summary 562

27 Oceanic Ecosystems 567

27.1 Introduction 567

27.2 Factors Influencing the Life and Distribution of Pelagic Organisms 567

27.3 Classification of Pelagic Regions 571

27.4 Functional Classification of Pelagic Systems 573

27.5 Vertical Zonation in Pelagic Ecosystems 575

27.6 Biodiversity of Pelagic Systems 577

Part IV Human Impacts and Solutions for Planet Ocean: Applied Marine Biology 581

28 Human Impacts on Marine Ecosystems 583

28.1 Historical Data 583

28.2 Biodiversity Loss 587

28.3 The Main Threats to Marine Life and Ecosystems 590

28.4 Synergistic Impacts on Marine Ecosystems 597

29 Marine Biodiversity Conservation 603

29.1 Introduction 603

29.2 Conservation Objectives 603

29.3 The Third Dimension of Marine Conservation 606

29.4 Conservation Strategies 606

29.5 Marine Protected Areas 608

29.6 Cumulative Impacts and Biodiversity Conservation 613

29.7 Conservation Frameworks 614

29.8 Legal Instruments 615

29.9 Science Challenges and Solutions – Moving Science to Policy? 616

29.10 How Science Can Contribute 616

30 Restoring Marine Habitats 619

30.1 A Decade For Ecosystem Restoration 619

30.2 Defining Ecological Restoration 620

30.3 A Global Plan for Marine Ecosystem Restoration 623

30.4 Restoring Fragile Marine Habitats 623

30.5 Restoration of Coral Reefs 625

30.6 Restoration of Seagrass Meadows 626

30.7 Restoration of Macroalgal Forests 627

30.8 Restoring Ecosystem Engineers: The Case of Coralligenous Outcrops 629

30.9 Restoration of Deep-Sea Habitats 630

30.10 Perspectives of Marine Ecosystem Restoration 631

31 How Far We Have Come: Past, Present, and Future Research on the Marine Biology of Planet Ocean 633

31.1 Introduction 633

31.2 The Birth of Marine Biology 634

31.3 The History of Ocean Exploration 636

31.4 Present and Future of Marine Biology 637

31.5 Application of Marine Technologies 644

31.6 Marine Biology Research in the Next Decade 645

Glossary 649

Index 675