Hydrology and the Management of Watersheds

Preface xiii

Definition of Terms xv

1 Watersheds, Hydrologic Processes, and Pathways 3

1 Introduction 7

Overview 7

Watersheds 10

Integrated Watershed Management 12

Sustainable Use and Development of Natural Resources 14

Watersheds, Ecosystem Management, and Cumulative Effects 20

Reconciling Watershed and Political Boundaries 21

Summary and Learning Points 24

References 24

Webliography 26

2 Hydrologic Cycle and the Water Budget 27

Introduction 27

Properties of Water 27

The Hydrologic Cycle 30

Energy and the Hydrologic Cycle 38

Water Flow in Soil 43

Water Flow on Land and in Stream Channels 47

Summary and Learning Points 47

References 48

3 Precipitation 49

Introduction 49

Precipitation Process 50

Rainfall 53

Snowfall 63

Summary and Learning Points 78

References 78

Webliography 79

4 Evaporation, Interception, and Transpiration 81

Introduction 81

The Evaporation Process 82

Evaporation from Water Bodies 83

Evaporation from Soil Surfaces 85

Interception 85

Transpiration 92

Potential Evapotranspiration 103

Estimating Actual Evapotranspiration 105

Summary and Learning Points 109

References 110

5 Infiltration, Pathways of Water Flow, and Recharge 113

Introduction 113

Infiltration 113

Pathways of Water Flow 125

Summary and Learning Points 138

References 138

6 Streamflow Measurement and Analysis 141

Introduction 141

Measurement of Streamflow 141

Methods for Estimating Streamflow Characteristics 148

Summary and Learning Points 170

References 171

Webliography 172

7 Groundwater and Groundwater–Surface Water Exchange 173

Introduction 173

Groundwater 174

Groundwater–Surface Water Exchanges 187

Summary and Learning Points 193

References 194

Webliography 195

2 Physical, Chemical, and Biological Linkages of Water Flow 197

8 Soil Erosion Processes and Control 199

Introduction 199

Surface Soil Erosion 199

Erosion from Gullies and Ravines 221

Soil Mass Movement 230

Summary and Learning Points 237

References 238

Webliography 241

9 Sediment Supply, Transport, and Yield 243

Introduction 243

Sediment Supply and Transport 244

Measurement of Sediment 255

Sediment Yield 258

Cumulative Watershed Effects on Sediment Yield 260

Summary and Learning Points 263

References 264

10 Fluvial Processes and Implications for Stream Management 267

Introduction 267

Fluvial Geomorphology 268

Valley and Stream Evaluation and Classification 272

Stream Classification 285

Summary and Learning Points 293

References 293

Webliography 295

11 Water-Quality Characteristics 297

Introduction 297

Chemistry of Precipitation 298

Physical Characteristics of Surface Water 300

Dissolved Chemical Constituents 311

Biological Characteristics 319

Groundwater Quality 323

Cumulative Effects 324

Summary and Learning Points 325

References 326

Webliography 328

3 Integrated Watershed Management 329

12 Managing Wildland Watersheds 333

Introduction 333

Forests 333

Woodlands 364

Rangelands 367

Upland–Downstream Considerations 371

Cumulative Watershed Effects 377

Summary and Learning Points 379

References 380

Webliography 387

13 Managing Riparian Communities and Wetlands 389

Introduction 389

Riparian Communities 389

Wetlands 401

Cumulative Effects 422

Summary and Learning Points 422

References 423

14 Watershed Management Issues 427

Introduction 427

Fragmentation of Watershed Landscapes 427

Water Harvesting 439

Best Management Practices 442

Regulatory Compliance 446

Climatic Variability 451

Insufficient Information for Decision Making 455

Summary and Learning Points 456

References 458

Webliography 461

15 Socioeconomic Considerations in Integrated Watershed Management 463

Introduction 463

Policies and Policy Processes 464

Planning and Implementation 470

Economic Appraisals 475

Summary and Learning Points 486

References 487

16 Tools and Emerging Technologies 489

Introduction 489

Generalized Hydrologic Simulation Models 490

Technologically Advanced Tools 495

Using the Stable Isotopes of Hydrogen and Oxygen 500

Summary and Learning Points 507

References 508

Webliography 511

Appendix: Units Commonly Used in Hydrologic Work, USA 513

Index 517

Color plates appear between pages 512 and 513