Table Of ContentSecond Edition
Wetland
Indicators
A Guide to
Wetland Formation, Identification, Delineation,
Classification, and Mapping
Second Edition
Wet land
Indicators
A Guide to
Wetland Formation, Identification, Delineation,
Classification, and Mapping
Ralph W. Tiner
Boca Raton London New York
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Library of Congress Cataloging‑in‑Publication Data
Names: Tiner, Ralph W.
Title: Wetland indicators : a guide to wetland identification, delineation,
classification, and mapping / Ralph Tiner.
Description: Second edition. | Boca Raton : Taylor & Francis, [2017]
Identifiers: LCCN 2016040248 | ISBN 9781439853696 (hard back : alk. paper)
Subjects: LCSH: Wetlands--United States. | Wetland ecology--United States. |
Plant indicators--United States.
Classification: LCC GB624 .T564 2017 | DDC 551.41/7--dc23
LC record available at https://lccn.loc.gov/2016040248
Visit the Taylor & Francis Web site at
http://www.taylorandfrancis.com
and the CRC Press Web site at
http://www.crcpress.com
To my friend and colleague Petrus Lourens Marinus Veneman (“Peter”)
for the countless hours shared discussing and investigating
wetlands and teaching wetland delineation.
Contents
Preface to the Second Edition ..........................................................................................................xv
Preface to the First Edition ............................................................................................................xvii
Acknowledgments ...........................................................................................................................xxi
Author ..........................................................................................................................................xxiii
Chapter 1 Wetland Definitions and Concepts for Identification and Delineation.........................1
Introduction ..................................................................................................................1
Definitions ....................................................................................................................1
Shaler’s Wetland Definition (1890)...............................................................................3
Scientific Wetland Definitions ......................................................................................4
Evolution of the U.S. Fish and Wildlife Service Wetland Definition ......................4
U.S. Fish and Wildlife Service Wetland Definition ................................................6
National Research Council Wetland Definition ......................................................7
Canadian National Wetland Definition ...................................................................9
Other Wetland Definitions for Conservation and Assessment ................................9
Ramsar Wetland Definition ..............................................................................10
Australian Wetland Definitions ........................................................................10
Brazil Wetland Definition .................................................................................11
China Wetland Definition .................................................................................12
Kenya Wetland Definition ................................................................................12
New Zealand Wetland Definition .....................................................................12
Republic of Korea Wetland Definition .............................................................13
South Africa Wetland Definition ......................................................................13
Uganda Wetland Definition ..............................................................................13
Zambia Wetland Definition ..............................................................................13
Wetland Definition for Remote Sensing for Global Applications ....................13
Regulatory Definitions ...............................................................................................14
Federal Clean Water Act Wetland Definition ........................................................14
Food Security Act Wetland Definition ..................................................................16
Selected State and Provincial Wetland Definitions ...............................................17
Field Application of Wetland Definitions ...................................................................23
Wetland Concepts for Identification and Delineation ................................................23
How Wet Is a Wetland? .........................................................................................25
Flooding or Waterlogging Duration .................................................................26
Frequency of Prolonged Wetness .....................................................................27
Critical Depth of Saturation..............................................................................27
Timing of Wetness ............................................................................................28
Wetland Hydrology Defined .............................................................................28
What Is the Significance of “Growing Season” for Defining Wetland
Hydrology? ............................................................................................................28
Evolution of the Growing Season Concept for Wetland Determinations .........29
Ecological Considerations for Defining the Critical Period for Wetland
Hydrology .........................................................................................................31
Current Concept of Growing Season for Wetland Delineation (2016) .............38
Are All Wetlands at Least Periodically Anaerobic, Reduced Environments? ......39
vii
viii Contents
Are Wetlands Simply Ecotones between Land and Water? ..................................40
Ecotonal Wetlands ............................................................................................41
Nonecotonal Wetlands ......................................................................................43
Do Wetlands Include All Riparian Areas? ............................................................46
Do Wetlands Eventually Become Drylands in a Natural Order of
Terrestrialization? ..................................................................................................47
Are Some Wetlands Ephemeral Features on the Landscape
and Cyclical in Occurrence? ..................................................................................50
References ..................................................................................................................52
Chapter 2 Wetland Formation and Hydrology ............................................................................63
Introduction ................................................................................................................63
Wetland Formation .....................................................................................................63
Climate ..................................................................................................................63
Topography ............................................................................................................66
Proximity to a Water Source .................................................................................75
Soils and Substrates ...............................................................................................78
Vegetation ..............................................................................................................79
Summary Remarks on Wetland Formation ...........................................................81
Wetland Hydrology ....................................................................................................83
Defining Aspects of Wetland Hydrology ..............................................................85
Water Budget .........................................................................................................88
Wetness Patterns across the United States ............................................................92
Wetness Patterns in Selected Areas around the Globe ..........................................94
South America ..................................................................................................94
Africa ................................................................................................................94
Southeast Asia ..................................................................................................94
Hydrology of Selected Wetland Types in North America .....................................95
Floodplain Wetlands .........................................................................................95
Northern Coniferous Swamps ........................................................................100
Hardwood and Mixed Hardwood Swamps .....................................................101
Atlantic White Cedar Swamps .......................................................................104
Cypress Swamps .............................................................................................105
Wet Flatwoods ................................................................................................106
Carolina Bays and Pocosins............................................................................108
Marshes ...........................................................................................................111
Wet Meadows ..................................................................................................113
Temporary Pools .............................................................................................114
Prairie Potholes ...............................................................................................117
Playas and Playa-Like Wetlands .....................................................................119
Bogs ................................................................................................................122
Fens .................................................................................................................124
Permafrost Wetlands .......................................................................................127
Tidal Wetlands ................................................................................................127
Geographically Isolated Wetlands ..................................................................130
Indicators of Wetland Hydrology .............................................................................130
Corps of Engineers Regional Indicators..............................................................131
Other Wetland Hydrology Indicators ..................................................................137
Contents ix
Indicators of Groundwater Discharge .................................................................139
Indicators of Long-term Hydrology.....................................................................140
Monitoring Wetland Hydrology ...............................................................................140
References ................................................................................................................142
Chapter 3 Plant Indicators of Wetlands and Their Characteristics ...........................................157
Introduction ..............................................................................................................157
Environmental Changes due to Flooding and Waterlogging ...................................158
Plant Adaptations to Flooding and Waterlogging ....................................................161
Morphological Adaptations .................................................................................164
Hypertrophied Stems Including Buttressed Trunks .......................................166
Hollow and Adaptable Stems..........................................................................170
Shallow Root Systems ....................................................................................171
Pneumatophores ..............................................................................................174
Looping Roots ................................................................................................175
Water Roots ....................................................................................................175
Adventitious Roots ..........................................................................................175
Soil Water Roots .............................................................................................179
Aerenchyma ....................................................................................................179
Hypertrophied Lenticels .................................................................................183
Oxidized Rhizospheres .......................................................................................184
Life-form or Habit Changes ................................................................................187
Seed Adaptations .................................................................................................188
Germination and Seedling Survival ....................................................................189
Accelerated Stem and Other Growth ..................................................................190
Wetland Plants: Hydrophytes ...................................................................................191
Evolving Concept of a Hydrophyte .....................................................................191
Plant Specificity ...................................................................................................193
Wetland Ecotypes ................................................................................................193
Using Plants to Identify Wetlands ............................................................................198
Wetland Plant Lists ..............................................................................................199
Field Indicators of Hydrophytic Vegetation ........................................................202
Concerns Interpreting FAC and FACU Species as Hydrophytes ........................202
Human Effects on Wetland Plant Distribution ....................................................206
Using Plants to Predict Environmental Conditions in Wetlands .............................206
Plants as Hydrology Indicators ............................................................................208
Plants as Indicators of Water Sources .................................................................208
Plants as Water Chemistry Indicators .................................................................211
Plants as Indicators of Pollution and Disturbance ...............................................214
Plants as Soil Type Indicators .............................................................................214
Plants as Indicators of Water Stress ....................................................................216
Plants as Indicators of Floristic Quality ..............................................................217
Plants as Indicators of Wetland Condition ..........................................................218
Useful Guides for Identifying Wetland Plants .........................................................219
Northeast ..................................................................................................................219
Southeast ..................................................................................................................219
Midwest ....................................................................................................................220
Interior West .............................................................................................................220
