Critical Transitions in Nature and Society

Acknowledgments xiii CHAPTER 1. Introduction 1 1.1 Coral Reef Collapse 2 1.2 The Birth of the Sahara Desert 3 1.3 Shifts in Societies 5 1.4 Content of this Book 6 Part I: THEORY OF CRITICAL TRANSITIONS CHAPTER 2. Alternative Stable States 11 2.1 The Basics 13 2.2 Some Mechanisms 25 2.3 Synthesis 36 CHAPTER 3. Cycles and Chaos 37 3.1 The Limit Cycle 37 3.2 Complex Dynamics 42 3.3 Basin Boundary Collision 50 3.4 Synthesis 54 CHAPTER 4. Emergent Patterns in Complex Systems 55 4.1 Spatial Patterns 56 4.2 Stability of Complex Interacting Networks 65 4.3 The Adaptive Cycle Theory 75 4.4 Synthesis 79 CHAPTER 5. Implications of Fluctuations, Heterogeneity, and Diversity 81 5.1 Permanent Change 82 5.2 Spatial Heterogeneity and Modularity 85 5.3 Diversity of Players 90 5.4 Synthesis 95 CHAPTER 6. Conclusion: From Theoretical Concepts to Reality 96 6.1 Alternative Stable States 96 6.2 Basins of Attraction 98 6.3 Resilience 101 6.4 Adaptive Capacity 103 6.5 Critical Transitions 104 6.5 Synthesis 104 PART II: CASE STUDIES CHAPTER 7. Lakes 109 7.1 Transparency of Shallow Lakes 110 7.2 Dynamics 125 7.3 Other Alternative Stable States 131 7.4 Synthesis 138 CHAPTER 8. Climate 139 8.1 Deep Time Climate Shifts 141 8.2 Glaciation Cycles 149 8.3 Abrupt Climate Change on Shorter Timescales 157 8.4 Synthesis 164 CHAPTER 9. Evolution 166 9.1 Introduction 166 9.2 Early Animal Evolution and the Cambrian Explosion 168 9.3 The End-Permian Extinction 172 9.4 The Angiosperm Radiation 174 9.5 From Dinosaurs to Mammals 176 9.6 Global Warming and the Birth of Primates, Deer, and Horses 177 9.7 In Search of the Big Picture 178 9.8 Synthesis 184 CHAPTER 10. Oceans 186 10.1 Open Ocean Regime Shifts 187 10.2 Coastal Ecosystems 201 10.3 Synthesis 213 CHAPTER 11. Terrestrial Ecosystems 216 11.1 Vegetation-Climate Shifts in Dry Regions 216 11.2 Small-Scale Transitions in Semiarid Vegetation 221 11.3 Boreal Forests and Tundra 226 11.4 The Rise and Fall of Raised Bogs 230 11.5 Species Extinction in Fragmented Landscapes 234 11.6 Epidemics as Critical Transitions 237 11.7 Synthesis 239 CHAPTER 12. Humans 240 12.1 Shifting Cells 242 12.2 Shifting Minds 243 12.3 Behavioral Lock-In 244 12.4 Inertia and Shifts in Group Attitudes 246 12.5 Societies in Crisis 250 12.6 Synthesis 257 CHAPTER 13. Conclusion: Critical Transitions in a Complex World 259 PART III: DEALING WITH CRITICAL TRANSITIONS CHAPTER 14. How to Know if Alternative Basins of Attraction Exist 265 14.1 Hints from Field Data 265 14.2 Experimental Evidence 270 14.3 Mechanistic Insight 273 14.4 Synthesis 280 CHAPTER 15. How to Know if a Threshold Is Near 282 15.1 The Theory: Signs of Upcoming Transitions 283 15.2 Precursors of Transitions in Real Systems 290 15.3 Reliablility of the Signals 293 15.4 Synthesis 294 CHAPTER 16. The Winding Road from Science to Policy 296 16.1 Exploiting Nature in the Smartest Way 297 16.2 Barriers to Good Solutions 303 16.3 Synthesis 309 CHAPTER 17. New Approaches to Managing Change 311 17.1 Promoting Good Transitions 312 17.2 Preventing Bad Transitions 320 17.3 Synthesis 324 CHAPTER 18. Prospects 326 18.1 The Delicate Issue of the Burden of Proof 326 18.2 Toward a Practical Science of Critical Transitions 327 Appendix 329 A.1 Logistic Growth 329 A.2 Allee Effect 332 A.3 Overexploitation 332 A.4 Competition between Two Species 334 A.5 Multispecies Competition 338 A.6 Predator-Prey Cycles 339 A.7 The Hopf Bifurcation 341 A.8 Stabilization by Spatial Heterogeneity 341 A.9 Basin Boundary Collision 344 A.10 Periodic Forcing 344 A.11 Self-Organized Patterns 345 A.12 Alternative Stable States in Shallow Lakes 347 A.13 Floating Plants 348 A.14 Contingency in Behavior 350 Glossary 353 Notes 359 Index 379