List of contributors ...................................... xiii
1 Peatland habitats ............................................ l
1.1 Wetlands, peatlands, and mires .......................... 2
1.2 Peatland habitats along wetness and chemical gradients .. 5
1.3 Origin of groundwater and trophic classes ............... 6
1.4 The main ecosystems: marsh, swamp, fen, bog ............. 7
1.5 Environmental gradients as a basis for a finer
classification ......................................... 13
1.6 Peatland classifications ............................... 17
2 Diversity of life in peatlands .............................. 21
2.1 Fungi and microorganisms ............................... 21
2.2 Protozoa ............................................... 27
2.3 Microalgae ............................................. 28
2.4 Lichens ................................................ 29
2.5 Plants ................................................. 30
2.6 Animals ................................................ 38
3 Adaptations to the peatland habitat ......................... 48
3.1 Plant adaptations to flooding and anoxic conditions .... 48
3.2 Plant adaptations to low nutrient availability ......... 53
3.3 The perfect peatland plant ............................. 60
3.4 Adaptations in animals ................................. 63
4 Sphagnum - the builder of boreal peatlands .................. 65
4.1 Morphology ............................................. 65
4.2 Capillarity and water-holding capacity ................. 68
4.3 Chemical adaptations ................................... 71
4.4 Nutrient conservation .................................. 73
4.5 Sphagnum life cycle .................................... 74
4.6 Diversity of Sphagnum .................................. 75
4.7 Sphagnum as an environmental indicator ................. 76
4.8 Biological interactions in Sphagnum .................... 78
4.9 Dispersal and colonization ............................. 81
4.10 Dynamics and persistence in Sphagnum assemblages ....... 83
5 Peat and organic soil ....................................... 85
5.1 Sedentation versus sedimentation ....................... 86
5.2 Organic versus mineral matter content .................. 87
5.3 Sampling the peat profile .............................. 88
5.4 Botanical composition .................................. 90
5.5 Degree of decomposition ................................ 92
5.6 Physical properties .................................... 95
5.7 Electrochemical and chemical properties ................ 98
5.8 Interrelationships of peat properties ................. 105
5.9 Organic soils (histosols) ............................. 107
6 The peat archives .......................................... 109
6.1 Peat fossils .......................................... 109
6.2 Other environmental indicators ........................ 116
6.3 The problem of dating profiles ........................ 118
6.4 The Blytt-Sernander scheme ............................ 121
6.5 Pleistocene peatlands ................................. 125
6.6 Wetland archaeology ................................... 125
7 Peatland succession and development ........................ 127
7.1 Peatland succession ................................... 127
7.2 Successional pathways ................................. 128
7.3 Processes of peatland formation ....................... 130
7.4 Ombrotrophication ..................................... 140
7.5 Detailed sequences of peatland development ............ 143
8 Peatland hydrology ......................................... 148
8.1 Water quantity ........................................ 148
8.2 Acrotelm and catotelm ................................. 155
8.3 Water balance ......................................... 157
8.4 Peatlands as regulators of water flow ................. 164
8.5 Water quality ......................................... 166
8.6 Variation in water chemistry along the bog-rich fen
gradient .............................................. 172
9 Nutrients, light, and temperature .......................... 175
9.1 Nutrients ............................................. 175
9.2 Light ................................................. 189
9.3 Temperature and other climatic factors ................ 192
10 Hydrological systems, hydromorphology, and peatland
patterns ................................................... 199
10.1 Hydrological systems .................................. 199
10.2 Hydromorphologic classification ....................... 206
10.3 The formation of peatland patterns .................... 226
11 Peatlands around the world ................................. 230
11.1 Areas of peatland ..................................... 230
11.2 Peatland areas used for agriculture, forestry, and
peat harvesting ....................................... 233
11.3 A brief global survey ................................. 234
11.4 Peatlands in Tierra del Fuego ......................... 236
DMITRI MAUQUOY AND KEITH D. BENNETT
11.5 Restiad bogs in New Zealand ........................... 241
BEVERLEY R. CLARKSON AND BRUCE D. CLARKSON
11.6 Tropical peatlands in south-east Asia ................. 248
ALJOSJA HOOIJER
12 Productivity and peat accumulation ......................... 254
12.1 Biomass and productivity .............................. 254
12.2 Decomposition ......................................... 259
12.3 Carbon flow in peatlands .............................. 264
12.4 Peat accumulation and its limits ...................... 266
13 Management, conservation, and restoration of peatlands ..... 274
13.1 Historical development of peatland use ................ 275
13.2 Agriculture on peatland ............................... 276
13.3 Forestry on peatland .................................. 278
13.4 Peat extraction ....................................... 281
13.5 Peatland conservation ................................. 284
13.6 Restoration, reclamation, and after-use ............... 287
13.7 Peatland societies and organizations .................. 294
14 Peatlands and climate change ............................... 296
14.1 Carbon pools in peatlands ............................. 297
14.2 Greenhouse gases and radiative forcing ................ 298
14.3 Methods to study environmental changes in peatland .... 299
14.4 Current carbon balance in peatlands ................... 301
14.5 Effects of climate change on peatlands ................ 302
14.6 Effects of drainage for forestry and agriculture ...... 310
14.7 Peat harvest .......................................... 312
14.8 Effects of climate change in permafrost regions ....... 313
14.9 Conclusions ........................................... 314
Glossary ................................................... 317
References ................................................. 321
Index ...................................................... 369
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