Preface to the second edition .................................. ix
Preface to the first edition ................................. xiii
Acknowledgments .............................................. xvii
1 Wetlands: an overview ........................................ 1
1.1 Definitions and distribution ............................ 2
1.2 Wetland classification .................................. 4
1.3 Wetland soils .......................................... 15
1.4 Flood tolerance: the primary constraint ................ 18
1.5 Secondary constraints produce different types of
wetlands ............................................... 22
1.6 Wetlands provide valuable functions and services ....... 28
1.7 Causal factors in wetland ecology ...................... 30
1.8 More on definitions and classification of wetlands ..... 34
Conclusion .................................................. 38
2 Flooding .................................................... 43
2.1 Flooding and humans: an old story ...................... 46
2.2 Some biological consequences of flooding ............... 48
2.3 A survey of water level fluctuations ................... 54
2.4 General relationships between wetlands and water
level fluctuations .....................................
2.5 Reservoirs, dams, and floodplains ...................... 68
2.6 Predicting consequences for wetlands ................... 74
Conclusion .................................................. 77
3 Fertility ................................................... 79
3.1 Fertility and plants ................................... 80
3.2 Infertile wetlands are constrained by low nutrient
levels ................................................. 84
3.3 Other issues related to fertility ...................... 88
3.4 Animals and fertility .................................. 94
3.5 Eutrophication: too much of a good thing ............... 96
3.6 Calcium interacts with fertility in peatlands ......... 104
3.7 Fertility and hydrology explain a great deal about
wetlands .............................................. 106
Conclusion ................................................. 107
4 Disturbance ................................................ 109
4.1 Disturbance has four properties ....................... 111
4.2 Disturbance triggers regeneration from buried
propagules ............................................ 112
4.3 Examples of disturbance controlling the composition
of wetlands ........................................... 113
4.4 Disturbances can create gap dynamics .................. 130
4.5 Measuring the effects of disturbance in future
studies ............................................... 133
Conclusion ................................................. 136
5 Competition ................................................ 139
5.1 Some examples of competition in wetlands .............. 141
5.2 Competition is often one-sided ........................ 145
5.3 Competition for light produces competitive
hierarchies ........................................... 146
5.4 Dominant plants are often larger than subordinate
plants ................................................ 148
5.5 Escape in space: competition in patches ............... 148
5.6 Escape in time: competition and disturbance ........... 149
5.7 Gradients provide another way of escaping in space .... 150
5.8 Competition gradients produce centrifugal
organization .......................................... 153
5.9 Rare animals are found in peripheral habitats: the
case history of the bog turtle ........................ 156
Conclusion ................................................. 158
6 Herbivory .................................................. 161
6.1 Some herbivores have large impacts on wetlands ........ 162
6.2 Wildlife diets document which animals eat which
plants ................................................ 166
6.3 Impacts of some other herbivores on wetlands .......... 168
6.4 Plants have defenses to protect them against
herbivores ............................................ 174
6.5 General patterns in herbivory ......................... 179
6.6 Three pieces of relevant theory ....................... 181
Conclusion ................................................. 186
7 Burial ..................................................... 189
7.1 Exploring rates of burial ............................. 192
7.2 Burial changes the species composition of wetlands .... 201
7.3 Burial has impacts on many animal species ............. 205
7.4 Sedimentation, sediment cores, and plant succession ... 206
7.5 Ecological thresholds: burial, coastlines, and sea
level ................................................. 207
7.6 So is sediment bad or good? ........................... 210
Conclusion ................................................. 211
8 Other factors .............................................. 213
8.1 Salinity .............................................. 214
8.2 Roads ................................................. 222
8.3 Logs and coarse woody debris .......................... 225
8.4 Stream type ........................................... 227
8.5 Human population density is becoming a key factor ..... 229
Conclusion ................................................. 233
9 Diversity .................................................. 235
9.1 Introduction to diversity in wetlands ................. 236
9.2 Four general rules govern the number of species in
wetlands .............................................. 238
9.3 Selected examples ..................................... 242
9.4 Some theory: a general model for herbaceous plant
communities ........................................... 255
9.5 More theory: the dynamics of species pools ............ 261
9.6 Conservation of biological diversity .................. 264
Conclusion ............................................ 265
10 Zonation: shorelines as a prism ............................ 269
10.1 The search for fundamental principles ................. 270
10.2 Shorelines provide a model system for the study of
wetlands .............................................. 271
10.3 Possible mechanisms of zonation ....................... 273
10.4 Zonation and changing sea level ....................... 286
10.5 Statistical studies of zonation ....................... 289
10.6 General lessons from analysis of zonation ............. 298
Conclusion ................................................. 299
11 Services and functions ..................................... 301
11.1 Wetlands have high production ......................... 302
11.2 Wetlands regulate climate ............................. 306
11.3 Wetlands regulate the global nitrogen cycle ........... 310
11.4 Wetlands support biological diversity ................. 314
11.5 Wetlands provide recreation and cultural services ..... 317
11.6 Wetlands reduce flood peaks ........................... 319
11.7 Wetlands record history ............................... 323
11.8 Adding up the services: WWF and MEA evaluate wetland
services .............................................. 325
Conclusion ................................................. 328
12 Research: paths forward .................................... 331
12.1 Some context: the great age of explorers .............. 332
12.2 Four basic types of information ....................... 334
12.3 Limitations to species-based research ................. 337
12.4 Empirical ecology ..................................... 338
12.5 Assembly rules driven by key factors .................. 341
12.6 Simplification through aggregation into groups ........ 347
12.7 Six tactical guidelines ............................... 360
Conclusion ................................................. 363
13 Restoration ................................................ 365
13.1 The importance of understanding wetland restoration ... 366
13.2 Three examples ........................................ 367
13.3 More on principles of restoration ..................... 373
13.4 More examples ......................................... 377
13.5 One big problem: invasive species ..................... 383
13.6 A brief history of restoration ........................ 385
Conclusion ................................................. 387
14 Conservation and management ................................ 391
14.1 Humans have greatly changed wetlands .................. 392
14.2 Wetlands have changed with time ....................... 397
14.3 Two views on conservation objectives .................. 400
14.4 Protection: creating reserve systems .................. 403
14.5 Problems and prospects of reserve systems ............. 411
14.6 More on restoration ................................... 415
14.7 So what shall we create with restoration? ............. 416
14.8 Indicators: setting goals and measuring performance ... 417
14.9 Humans as the biggest problem ......................... 424
Conclusion ................................................. 425
References .................................................... 427
Index ......................................................... 476
The color plates are situated between pages 238 and 239
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