Wetlands - swamp, marsh, bayou, tundra and bog - are places that are rarely visited and often misunderstood but they have, in fact, conspicuous roles in the physical, biological and cultural geography of the world. They are intrinsically beautiful environments where one may see the natural and essential values in the interaction of water, soil, vegetation, wildlife, and humans. Wetlands occur at the confluence of unique terrestrial, hydrological and climatic conditions that give rise to some of the most biodiverse regions of the world. They also play vital roles in the cycling and storage of key nutrients, materials and energy through the Earth's system. A complete study of wetland environments requires the assessment of their physical and biological attributes, properties and functions of these ecosystems, and the economic, political and social aspects that mediate their use globally. A systems approach is taken throughout this book which emphasizes the interactions between these elements of wetland ecosystems. Moreover, selected case studies from across the world are used to illustrate wetland characteristics and circumstances. This book is intended to foster a greater awareness and appreciation of wetlands, promote a culture of conservation and wise management, and spread the knowledge that wetlands are important, indeed crucial, elements of the global environment. Our attempts to understand, manage and enhance wetlands in the twenty-first century are part of the larger effort to maintain a sustainable Earth. Readership: Introductory or intermediate level undergraduates taking courses on wetland environments Additional resources for this book can be found at: www.wiley.com/go/aber/wetland.

InhaltsangabePreface: Why wetlands? xi Acknowledgements xiv Part I 1 Wetland overview 1 1.1 Introduction 1 1.2 How much and where 4 1.3 Wetland trends 8 1.4 Wetland preservation and protection 10 1.5 Wetland science 11 1.6 Book approach and outline 13 1.7 Summary 13 2 Wetland criteria 15 2.1 Definitions 15 2.2 Water 16 2.3 Soil 18 2.4 Vegetation 20 2.5 Wetland classification 22 2.6 Peatland 24 2.7 Anthropogenic dimensions of wetlands 27 2.8 Summary 28 3 Methods in wetland research 30 3.1 Introduction 30 3.2 Remote sensing 31 3.2.1 Image resolution and interpretability 32 3.2.2 Wetland image interpretation 35 3.2.3 Macrolevel systems 37 3.2.4 Mesolevel systems 41 3.2.5 Microlevel systems 42 3.3 Maps and geographic information systems 46 3.4 Physical ground-based methods 48 3.4.1 Surface methods 48 3.4.2 Subsurface methods 51 3.5 Flora, fauna and ecological monitoring and survey methods 53 3.6 Social science methods and techniques 56 3.7 Summary 57 Part II 4 Wetland hydrology 58 4.1 Introduction 58 4.2 Surface and ground water 61 4.3 Floods and flooding 64 4.4 Hydrologic functions of streams and wetlands 65 4.5 Hydrochemistry 68 4.6 Summary 70 5 Wetland soil 72 5.1 Introduction 72 5.2 Brief history and soil classification 73 5.3 Hydric soil criteria 78 5.4 Mineral and organic hydric soils 79 5.5 Submerged wetland substrates 81 5.6 Summary 82 6 Wetland vegetation 86 6.1 Plant adaptations 86 6.1.1 Structural adaptations 86 6.1.2 Biochemical adaptations 88 6.2 Ecological categories 89 6.2.1 Shoreline plants 90 6.2.2 Emergent plants 92 6.2.3 Floating plants 94 6.2.4 Submerged plants 96 6.2.5 Plant zonation 97 6.3 Indicator categories 99 6.4 Plant hardiness zones 101 6.5 Invasive plant species 102 6.6 Summary 105 7 Wetland wildlife 107 7.1 Introduction 107 7.2 Wetland invertebrates 108 7.2.1 Insects 108 7.2.2 Mosquitos 110 7.2.3 Corals 111 7.3 Wetland vertebrates 113 7.3.1 Amphibians 113 7.3.2 Reptiles 115 7.3.3 Birds 117 7.3.4 Mammals 125 7.4 Invasive animal species 130 7.5 Summary 132 Part III 8 Wetland change 135 8.1 Introduction 135 8.2 Hydroseral succession 136 8.3 Sealevel change and crustal movements 139 8.3.1 Glacial eustasy 139 8.3.2 Glacial isostasy 141 8.3.3 Complicated responses 141 8.3.4 Modern sea-level rise 143 8.4 Climate change 147 8.4.1 Climate basics 147 8.4.2 Climate and wetlands 150 8.5 Fire 152 8.6 Summary 154 9 Wetlands through time 156 9.1 Introduction 156 9.2 Coal 157 9.2.1 Paleozoic coal 157 9.2.2 Cretaceous-Tertiary coal and lignite 158 9.3 Amber 160 9.4 Pleistocene and Holocene wetlands 163 9.4.1 Nordic region 164 9.4.2 North America 167 9.4.3 Tropics and Antarctica 171 9.4.4 Holocene climate and early man 171 9.5 Summary 173 10 Environmental cycles and feedback 175 10.1 Biogeochemical cycles 175 10.1.1 Wetland elements 175 10.1.2 Nitrogen 175 10.1.3 Phosphorus, potassium and sulfur 177 10.2 Carbon cycle 179 10.2.1 Carbon reservoirs 179 10.2.2 Carbon balance 179 10.2.3 Carbon gases and climatic feedback 180 10.3 Fossil fuels 181 10.3.1 Fossil-fuel consumption 181 10.3.2 Coal mining and acid rain 183 10.3.3 Estonian oil shale 184 10.4 Human experiment 185 10.5 Summary 187 Part IV 11 Wetland services, resources and valuation 190 11.1 Human use of wetland ecosystems 190 11.2 Ecosystem services 191 11.2.1 Habitats 191 11.2.2 Wetlands and biogeochemical cycles 194 11.2.3 Storm surge and coastal flood protection 195 11.3 Hydrological services 196 11.3.1 Flood abatement 196 11.3.2 Water quality 196 11.3.3 Water storage and diversion 197 11.4 Economic services 199 11.4.1 Extractive industries 199 11.4.2 Pearl production 204 11.4.3 Ser

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