Forest Hydrology and Catchment Management: An Australian Perspective

Preface
Contents
List of Symbols and Units Used in the Book
List of Figures
1 The Basics of Catchment Hydrology
1.1 About the Hydrologic Cycle
1.1.1 The Hydrologic Cycle (and Forests)
1.1.2 Critiquing the Hydrologic Cycle
1.1.3 Ownership of the Hydrologic Cycle and the World’s Water
1.2 About Water Catchments and Stream Networks
1.3 Topographic Analysis and Catchment Boundaries
1.3.1 Catchment Flow Vectors and Streamlines
1.3.2 Defining Catchment Boundaries for a Specific Stream Cross-Section
1.4 Stream Networks
1.5 Hydrologic Units and Catchment Arithmetic
1.6 Introduction to Hydrographs and Averaging of Units
1.6.1 Runoff Expressed in Depth Units
1.6.2 The Instantaneous Hydrograph
1.7 How Does Forest Hydrology Differ from Hydrology?
1.8 What is Different About Australian Forest Hydrology?
References
2 Hydrologic Measurements and the Water Balance
2.1 Introduction
2.2 Basics of Measurement on a Catchment
2.2.1 Rainfall and Hyetograph Measurement
2.2.2 Hydrograph Measurement
2.2.3 Measurements of Slope Water Storage
2.2.4 Measurement of Plant Water Use
2.3 Analysis of Streamflow Hydrographs
2.3.1 Flow Separation Analysis
2.4 Using Field Data to Form a Water Balance
2.5 Using “Zhang Curves” to Estimate Water Balance
2.5.1 Percentage Runoff and Rainfall Elasticity Using Zhang Curves
References
3 The Fundamental Building Blocks—First-Order Catchments
3.1 Introduction
3.2 The Dominance of “Headwater Streams”
3.3 The Prototypical First-Order Catchment, and Streams
3.4 Groundwater Outflow Versus Downslope Soil Movement
3.5 Colluvium and Bedrock Erosion
3.6 Moving Upstream—Can We Define Zero-Order Streams?
3.6.1 Ephemerality of Low-Order Streams
3.7 Beds and Streams
3.8 Hydrologic Characteristics of Forested Catchment Soils
3.9 Continuum Levels
3.10 Characteristic Outflow Behaviour of Catchment Elements
3.11 Similitude and Scaling of Catchment Processes
References
4 Dynamics of Catchment and Slope Processes
4.1 The Role of Science and Maths in Slope Dynamics
4.2 Overview of Dynamics of Slope Processes
4.3 The Stream Channel as a Connecting Link
4.4 Overland Flow and Slope Infiltration
4.4.1 Measuring Infiltration
4.5 Saturated (Groundwater) and Unsaturated Flow
4.5.1 Applications of Groundwater Theory to Model Forest Slopes
4.5.2 “Perched” Groundwater and “Deep” Groundwater
4.5.3 Does a “Wave” of Groundwater Recharge Occur?
4.6 Slope Evaporation
4.7 Hewlett’s Variable Source Area Concept of Stream Runoff
4.8 Use of Hydrographs to Examine Dynamic Processes
4.9 Exciting Future Directions for This Field
References
5 Field Measurement of Water Use of Forests
5.1 Why Study This?
5.2 Paired Catchment Experiments
5.2.1 What is a Paired Catchment Project?
5.2.2 An Example of a Paired Catchment Project: Croppers Creek
5.2.3 Traditional Approach to Paired Catchment Calibration and Analysis
5.2.4 A Modern Example of Paired Catchment Statistical Treatment
5.2.5 What Time Units to Use?
5.2.6 How Long Does Calibration Need to Be?
5.2.7 Where Do Paired Catchments Sit in the World of Experiments?
5.2.8 Paired Catchment Projects in Australia
5.3 Single Catchment Studies of Water Use
5.4 Plot Measurements of Water Balance
5.4.1 Case Study: Rachel Nolan and Impact of Fires
5.4.2 Advantages and Disadvantages of Plot Hydrology Work
5.4.3 Where Do Plots Sit in the World of Experiments?
5.4.4 “Closing the Water Balance” on Plots
5.5 The Scaling Issue
5.5.1 Spreadsheet Approach of Weighted Assessment
5.5.2 Modelling Approach to Scaling
5.5.3 Hydrologic Modelling from First Principles of Vegetation Growth
5.5.4 Scaling up Controversies
References
6 Hydrology of Managed Eucalypt Forest
6.1 Introduction
6.1.1 Sources of Information and the Role of Science
6.2 Fog Drip and Interception by Native Eucalypt Forests
6.2.1 Fog Drip
6.2.2 Canopy Interception
6.3 Basic Runoff Curves for Native Eucalypt Forest
6.4 Mountain Ash Water Use and Runoff Curves
6.4.1 Quantifying the Yield Decline—“Kuczera Curves”
6.4.2 Response to Logging
6.4.3 Other Melbourne Water Paired Catchment Logging Experiments
6.4.4 The “BISY” Model of Ash Water Yield (Age and Rainfall)
6.4.5 Later Work on Mountain Ash Age–Yield Relationships
6.5 Hydrology of Jarrah Forests
6.5.1 The Annual Flow Cycle
6.5.2 Evapotranspiration and Water Yield
6.5.3 Water Yield Changes After Forest Treatment
6.5.4 Mining and Jarrah Hydrology
6.5.5 Effect of Jarrah Dieback on Water Yield
6.5.6 Obsolescence of the Jarrah Forests as Water Supply Catchments
6.6 Is There an “Age-Yield” Response for Non-ash Eucalypts?
6.6.1 Yambulla Paired Catchment and Plot Studies
6.6.2 Karuah Paired Catchment Project
6.6.3 Tantawangalo Paired Catchment Project
6.6.4 Political Aspects of Native Forest Water Use
6.7 Thinning of Native Forests for Water Production
6.7.1 Thinning of Mountain Ash Forests
6.7.2 Thinning of Mountain Forest at Tantawangalo
6.7.3 Thinning of Jarrah
References
7 Non-eucalypt Forest Hydrology—Rainforests and Brigalow
7.1 About Rainforests
7.2 Wyvuri Paired-Catchment Experiment
7.2.1 The Experimental Catchments
7.2.2 The Effects of Clearing on the North Creek Hydrology
7.2.3 Sub-Surface Hydrology Processes in the Catchments
7.3 A Plot Approach to Water Balance of Rainforests
7.4 Rainforests—The Darlings of the Urban Dwellers?
7.5 Hydrochemistry of Rainforests
7.6 Brigalow and the Brigalow Catchment Study
7.6.1 The Brigalow Catchment Study
7.6.2 Gilgai
References
8 Hydrology of Man-Made Forests (Plantations)
8.1 Introduction
8.1.1 What is Different About Plantations?
8.1.2 Are All Plantations the Same?
8.1.3 Defining the “Water Use” of a Plantation
8.2 Runoff Curve Approaches to Plantation Water Use
8.2.1 “Zhang Curves”
8.2.2 “Holmes and Sinclair” Relationships
8.2.3 Nänni Curves
8.3 Water Use of Radiata Pine on Well-Drained Sites
8.3.1 Absolute Water Use
8.3.2 Relative Change in Water Use
8.4 Water Use of Eucalyptus Plantations
8.5 Water Use When Plantations Can Tap Groundwater
8.6 Paired-Catchment Work—Eucalypts Versus Pasture in SW Victoria
8.7 Other Australian Plantation Species
8.8 Plantation Water Issues Around the World
8.8.1 Eucalyptus Plantations
8.9 Balancing the Hydrologic Benefits of Plantations
References
9 Impacts of Burning on Catchment Hydrology and Management
9.1 Introduction
9.1.1 Suddenly—An International Focus on Burning and Water Issues!
9.2 Burning of the Croppers Creek Hydrologic Project in 2006
9.2.1 The Dreaded “Spike Hydrograph” and Other Burning Effects
9.3 What Happens to Hydrology When a Catchment is Burnt
9.3.1 Long-Term Impacts on Water Yield
9.3.2 Soil Heating and “Brick” Formation
9.3.3 Water Repellency and Soil Infiltration
9.3.4 Runoff from Water-Repellent Catchments
9.3.5 Erosion from Burnt Catchments
9.3.6 Water Quality Impacts from Burnt Catchments
9.3.7 The “Reseeder” Versus “Resprouter” Dichotomy
9.3.8 Twice-Burnt Areas
9.3.9 The Burnt Areas Become Hotter!
9.4 Aridity and Catchment Formation
9.4.1 The Role of Fire in the Coevolution of Catchments and Vegetation
9.5 Post-Fire Hydrologic Rehabilitation
9.6 Case Study: The Macalister River Floods of 2007
9.7 Future Fire Hydrology Research in Australia
References
10 Water Quality and Nutrient Issues for Small Catchments
10.1 Why Measure Water Quality?
10.2 Planning a Water Quality “Campaign”
10.2.1 The Pure Water of Mountain Streams Makes Measurement Difficult!
10.2.2 What Parameter Should I Measure?
10.2.3 Water Sampling and Statistical Sampling Issues
10.2.4 Technology to the Rescue?
10.2.5 Water Quality Computations
10.2.6 Water Quality Snapshots
10.2.7 Statistical Characteristics of Water Resources Data
10.3 Case Study 1: The Croppers Creek Water Quality Study
10.3.1 Effects of Clearing and Planting with Radiata Pine
10.3.2 Effects of Fertilisers
10.3.3 Effects of Herbicides
10.3.4 Long-Term Effects on Water Quality
10.3.5 Use of Biota as a Measure of Water Quality
10.3.6 Did the Croppers Project Provide the Information Required?
10.4 Case Study 2: Water Quality Effects of Forest Roads
10.5 Impacts of Bushfires on Water Quality
10.6 Protection of Water Quality in Forestry Management
10.7 The Future of Forest Water Quality Studies
References
11 Flooding Forests
11.1 Introduction
11.1.1 What is Meant by “Flooding Forests”?
11.1.2 The Distinction Between Riparian Forests and Flooding Forests
11.1.3 Ecological Adaptation for Survival During Flooding
11.1.4 The Forest as a Hydrologic Refugium
11.1.5 Australian and International Examples of Flooding Forests
11.1.6 Threats to Flooding Forests
11.2 Case Study 1: River Red Gum Forests of the River Murray
11.3 Case Study 2: Swamp Cypress Forests of the Atchafalaya Basin
11.4 Quantification of the Flooding Regime
11.4.1 Sources of Flood Water
11.4.2 Annual Flood Frequency and Annual Flood Duration
11.4.3 Flood Seasonality
11.4.4 Methods for Quantification
11.4.5 Chaotic Hydrologic Systems
11.5 Negotiations with River Managers on Forest Issues
References
12 Salinity and Forests
12.1 What Do We Mean by “Salt” and “Salinity”?
12.2 Impacts of Sodium and Sodicity on Soil Physical Properties
12.3 Measurement of Salt Levels
12.4 Where Did the Salt Originally Come From?
12.4.1 Meteorological Salt
12.4.2 Connate Salt
12.5 Concentration of Salt by Evaporation
12.6 Sodium Toxicity in Plants
12.7 Use of Saline Water for Eucalypt Irrigation
12.8 Salt and Native Forests
12.8.1 Impacts of Clearing of Native Forests on Salt Loads
12.8.2 Trees Holding Salt in the Soil
12.8.3 Salt Liberation by Clearing of Brigalow Forests
12.8.4 Will Salt Accumulate Under Trees to the Point that the Trees Die?
12.9 Rehabilitation Plantings on Salinized Landscapes
References
13 Climate Change, Drought, and Forest Hydrology
13.1 The World is Getting Warmer
13.2 Paleo-Evidence of Past Change
13.3 Definitions of Climate and “Extreme Events”
13.4 Can We Define “Climate Change” in Hydrologic Terms?
13.5 Annual Variation of Rainfall and Streamflow and the Hurst Effect
13.6 Let Us Do Our Own Bit of Modelling….
13.7 Long Excursions from the Mean
13.8 Drought in Australia and Other Places
13.8.1 Tree Ring Quantification of Drought
13.8.2 Quantifying Drought
13.9 How Might Climate Change Impact Australian Forest Hydrology?
13.9.1 The “Budyko Framework”
13.9.2 Application of Budyko Theory to the Murray-Darling Basin
13.9.3 Does This Give a Methodology for Assessing Climate Change Impacts on Forests
13.10 Case Study 1: A Step Change in Jarrah Forest Rainfall
13.11 Case Study 2: Enhanced Forest Fire Risk
13.12 Is, then, Climate Change Impacting Australia’s Forest Hydrology?
References
14 Small Streams and Big Rivers
14.1 Introduction
14.1.1 Specific Questions
14.1.2 Research Approaches and Confounding by Multiple Factors
14.2 Stream and River Degradation
14.2.1 “Pioneer Devastation” (1) Upper Murrumbidgee River
14.2.2 Pioneer Devastation (2) “Sludge” and the Barmah Choke
14.3 Impacts of Forest Harvesting on Larger Catchment Flows
14.3.1 Case Study 1: Impacts of Forestry on River Murray Flows
14.3.2 Case Study 2: Does Logging Increase Peak Flows?
14.3.3 General Comments on Ascribing “Good” and “Bad”
14.4 Public Perceptions About Beneficial Effects of Forests
14.4.1 “The Theory of Himalayan Degradation”
14.4.2 Wholescale Afforestation as a Flood Control Measure
14.5 Optimising Forest Management for Hydrologic Goals
References
15 Catchment Management Issues Worldwide
15.1 Issues, Issues Galore in Catchment Management
15.2 The Basic Water Supply Catchment
15.3 World’s Best Practice in Catchment Management
15.4 The Public and Attitudes on Catchment Management
15.4.1 Sydney’s Giardia Crisis
15.5 “Open” or “Closed” Catchment
15.5.1 What is a “Closed Catchment?”
15.5.2 Advantages and Disadvantages of Closed Catchments
15.6 How Much Catchment Do We Need to Supply a City?
15.7 The Concept of Payment for Catchment Services
15.8 Economics of Forested Catchment Issues
15.8.1 Without Water, There is no Economy!
15.8.2 High-Rainfall Catchments Can Be “Cash Cows”
15.8.3 Long Time Periods Make Financial Comparisons Difficult
15.8.4 Valuation of Water and Other Products
15.8.5 Managing for Catchment Resilience
15.9 Dealing with Disasters to the Catchment’s Forests
15.10 Catchment Protection Issues
15.10.1 Road Drainage Management
15.10.2 Buffer Strips and Stream Protection
15.11 Two Case Studies of Catchment Management
15.11.1 City of Ballarat (Australia)
15.11.2 Quabbin Reservoir (United States of America)
15.12 And Finally
References
Afterword
Appendix Map of Australia Showing Locations Mentioned in the Text
Index