Methods of Soil Analysis: Physical & Mineralogical Methods (Sssa Book Series No 5)

Description

This is the classic text on physical and mineralogical characteristics of soils and how they relate to each other and to chemical properties. Methods of Soil Analysis, Part 1 provides a uniform set of procedures that can be used by soil scientists, engineers, students and more to conduct precise soil analysis. Also available: The American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America are prominent international scientific societies headquartered in Madison, Wisconsin. The Societies specialize in peer-reviewed, high-quality science titles for a wide variety of audiences. 00 0 Half-Title Page Series Page Title Page Copyright Page CONTENTS DEDICATION FOREWORD PREFACE CONTRIBUTORS Conversion Factors for SI and non-SI Units 1 2 Chapter 2: Sampling 2-1 Introduction 2-2 Variation of Soils 2-3 Sampling Plans 2-3.1 Judgment Sample 2-3.2 Simple Random Sample 2-3.3 Stratified Random Sample 2-3.4 Systematic Sample 2-4 Sources of Errors 2-5 Subsampling 2-6 Composite Samples 2-7 References 3 Chapter 3: Geostatistical Methods Applied to Soil Science 3-1 Introduction 3-2 Quantification of Spatial Interdependence 3-2.1 Correlograms 3-2.2 Variograms 3-2.3 Range of Influence and Integral Scale 3-3 Punctual Kriging 3-3.1 Example 4. Punctual Kriging-One-dimensional 3-3.2 Example 5. Punctual Kriging-Two-dimensional 3-3.3 Example 6. Kriging Map for Salinity 3-3.4 Example 7. Efficiency of Sampling-Infiltration 3-4 Block Kriging 3-4.1. Example 8. Block Kriging for Salinity 3-5 Sampling Strategies for Specified Estimation Error 3-5.1 Example 9. Sampling Error 3-6 Further Applications 3-6.1 Universal Kriging 3-6.2 Co-Regionalization 3-6.3 Conditional Simulation 3-6.4 Miscellaneous Comments and Notes 3-7 Discussion 3-8 References 4 Chapter 4: Extraneous Values 4-1 Introduction 4-2 The Problem of Estimation (Use of the Median and Range) 4-3 Confidence Limits as Estimates 4-4 The Problem of Designating Extraneous Values 4-5 Recommended Rules for Designating Extraneous Values 4-6 Recommended Rules for Estimation in the Presence of Extraneous Values 4-7 Test of Hypotheses (Trimmed and Winsorized t-Tests) 4-8 References 5 Chapter 5: Pretreatment for Mineralogical Analysis 5-1 General Introduction 5-2 Removal of Soluble Salts and Carbonates 5-2.1 Introduction 5-2.2 Methods 5-3 Removal of Organic Matter 5-3.1 Introduction 5-3.2 Method 5-4 Removal of Free Iron Oxides 5-4.1 Introduction 5-4.2 Method 5-5 Particle-Size Separations 5-6 References 6 Chapter 6: Oxides, Hydroxides, and Aluminosilicates 6-1 Introduction 6-2 Quartz and Feldspars 6-2.1 Introduction 6-2.2 Principles 6-2.3 Method 6-3 Noncrystalline Aluminosilicates and Hydrous Oxides by Acid Ammonium Oxalate in the Dark 6-3.1 Introduction 6-3.2 Principles 6-3.3 Method 6-4 Free Iron-Aluminum Oxides and Hydroxides 6-4.1 Introduction 6-4.2 Principles 6-4.3 Method 6-5 Poorly Crystalline Aluminosilicates 6-5.1 Introduction 6-5.2 Principles 6-5.3 Method 6-6 Smectite, Vermiculite, and CEC Hysteresis 6-6.1 Introduction 6-6.2 Principles 6-6.3 Method for Vermiculite 6-6.4 CEC Hysteresis of Noncrystalline Aluminosilicates 6-7 Rutile and Anatase 6-7.1 Introduction 6-7.2 Principles 6-7.3 Method 6-8 References 7 Chapter 7: Thermal Analysis Techniques 7-1 Introduction 7-2 Principles of Reactions and Analysis 7-2.1 General Principles 7-2.2 Differential Thermal Analysis 7-2.3 Differential Scanning Calorimetry 7-2.4 Thermogravimetry 7-3 Methods 7-3.1 Differential Thermal Analysis 7-3.2 Differential Scanning Calorimetry 7-3.3 Thermogravimetry 7-4 References 8 Chapter 8: Petrographic Microscope Techniques 8-1 General Introduction 8-2 Grains 8-2.1 Introduction 8-2.2 Heavy-liquid Separations 8-2.3 Slide Preparation 8-2.4 Grain Analyses 8-3 Thin Sections 8-3.1 Introduction 8-3.2 Sampling 8-3.3 Impregnation 8-3.4 Cutting and Finishing 8-3.5 Observations and Interpretations 8-4 Applications 8-5 Glossary of Micromorphology Terms 8-6 References 9 Chapter 9: Magnetic Methods 9-1 Introduction 9-2 Magnetic Susceptibility 9-2.1 Principles 9-2.2 Apparatus 9-2.3 Procedure 9-2.4 Comments 9-3 Electron Spin Resonance (ESR) 9-3.1 Principles 9-3.2 Apparatus 9-3.3 Procedure 9-3.4 Comments 9-4 Nuclear Magnetic Resonance (NMR) 9-4.1 Principles 9-4.2 Apparatus 9-4.3 Procedure 9-4.4 Comments 9-5 References 10 Chapter 10: Electron Microprobe Analysis 10-1 Introduction 10-2 Principles 10-3 Instrument 10-3.1 Electron Source and Optics 10-3.2 Specimen Stage and Optical Microscope 10-3.3 Electron-beam Scanning Devices 10-3.4 X-ray Detectors 10-4 Specimen Preparation 10-4.1 Specimen Mounting 10-4.2 Specimen Polishing 10-4.3 Surface Coating 10-5 Quantitative Analysis 10-5.1 Instrumental Factors 10-5.2 Matrix Corrections 10-6 Monte Carlo Method 10-7 Applications in Soil Analysis 10-7.1 Chemical and Biological Weathering 10-7.2 Phosphates in Soils 10-7.3 Ferromanganiferous Concretions 10-7.4 Silicate Minerals 10-7.5 Geochemical Investigations 10-8 Reference Books 10-9 References 11 Chapter 11: Infrared Spectrometry 11-1 General Introduction 11-2 Principles 11-2.1 Origin of Spectra 11-2.2 Infrared Spectrometers 11-2.3 Organic Spectra 11-2.4 Inorganic Spectra 11-3 Sample Preparation 11-3.1 Gases 11-3.2 Liquids 11-3.3 Solids 11-3.4 Techniques of Sample Presentation 11-4 Functional-Group and Qualitative Analysis of Organic Compounds 11-4.1 Materials 11-4.2 Procedure 11-4.3 Interpretation of Spectra 11-5 Identification and Characterization of Amorphous and Crystalline Inorganic or Mineral Phases 11-5.1 Materials 11-5.2 Procedure 11-5.3 Interpretation of Spectra 11-6 Quantitative Analysis 11-6.1 Introduction 11-6.2 Materials 11-6.3 Procedure 11-6.4 Calibration Curve 11-6.5 Comments 11-7 Spectral Data Collection and Manipulation 11-8 References 12 Chapter 12: X-Ray Diffraction Techniques 12-1 General Introduction 12-2 Principles of X-Ray Diffraction 12-3 Preparation of Samples 12-3.1 Introduction 12-3.2 Sample Dispersion for Particle-Size Segregation 12-3.3 Separation of Particle-Size Fractions 12-3.4 Saturation of Exchange Complex 12-3.5 Solvation with Glycerol 12-3.6 Mounting 12-4 X-Ray Examination of Samples 12-4.1 Special Apparatus 12-4.2 Procedure 12-4.3 Comments 12-5 Criteria for Differentiation of Phyllosilicate Species 12-6 Qualitative Interpretation of Diffraction Patterns 12-6.1 Direct Comparison 12-6.2 Measurement of Diffraction Spacings 12-6.3 Identification of Mineral Species 12-7 Quantitative Interpretation of Diffraction Patterns 12-8 References 13 Chapter 13: Bulk Density 13-1 General Introduction 13-2 Core Method 13-2.1 Introduction 13-2.2 Method 13-3 Excavation Method 13-3.1 Introduction 13-3.2 Method 13-4 Clod Method 13-4.1 Introduction 13-4.2 Method 13-5 Radiation Methods 13-5.1 Introduction 13-5.2 Methods 13-6 References 14 Chapter 14: Particle Density 14-1 Introduction 14-2 Principles 14-3 Pycnometer Method 14-3.1 Special Apparatus 14-3.2 Procedure 14-4 Submersion Method 14-4.1 Special Apparatus 14-4.2 Procedure 14-5 Comments 14-6 References 15 Chapter 15: Particle-size Analysis 15-1 Introduction 15-2 Principles 15-2.1 Pretreatment and Dispersion Techniques 15-2.2 Sieving 15-2.3 Sedimentation 15-3 Sample Preparation 15-3.1 Apparatus 15-3.2 Method 15-3.3 Comments 15-4 Pipet Method 15-4.1 Apparatus and Reagents 15-4.2 Procedures 15-4.4 Comments 15-5 Hydrometer Method 15-5.1 Apparatus and Reagents 15-5.2 Procedure 15-6 Other Methods 15-7 References 16 Chapter 16: Specific Surface 16-1 Introduction 16-2 Principles 16-2.1 Adsorption Isotherms 16-2.2 Retention of Polar Liquids 16-3 Method 16-3.1 Special Apparatus 16-3.2 Chemicals 16-3.3 Procedure 16-3.4 Comments 16-4 References 17 Chapter 17: Aggregate Stability and Size Distribution 17-1 Introduction 17-1.1 Definition and General Approaches 17-1.2 Forces Involved in Aggregation 17-2 Principles 17-2.1 Dry Aggregates 17-2.2 Wet Aggregates 17-2.3 Methods of Expressing the Size Distribution of Aggregates 17-3 Methods 17-3.1 Dry Aggregates: Equipment and Procedure for Determining Size Distribution and Resistance to Abrasion 17-3.2 Wet Aggregates 17-4 References 18 Chapter 18: Porosity 18-1 Introduction 18-2 Total Porosity 18-2.1 Calculation from Particle and Bulk Densities 18-2.2 Gas Pycnometer Method 18-3 Pore Size Distribution 18-3.1 Water Desorption Method 18-3.2 Mercury Intrusion Method 18-4 References 19 Chapter 19: Penetrability 19-1 Introduction 19-2 Principles 19-3 Pocket Penetrometer 19-3.1 Introduction 19-3.2 Method 19-4 Cone Penetrometer 19-4.1 Introduction 19-4.2 Method 19-5 Small-Diameter Friction-Sleeve Cone Penetrometer 19-5.1 Introduction 19-5.2 Method 19-6 References 20 Chapter 20: Compressibility 20-1 Introduction 20-2 Principles 20-3 Methods 20-3.1 Special Apparatus 20-3.2 Procedure 20-3.3 Comments 20-4 References 21 21 Water Content 21-1 General Information 21-2 Direct Methods 21-2.1 General Principles 21-2.2 Gravimetry with Oven Drying 21-2.3 Gravimetry with Microwave Oven Drying 21-3 Indirect Methods 21-3.1 Introduction 21-3.2 Electrical Conductivity and Capacitance 21-3.3 Neutron Thermalization 21-3.4 Gamma Ray or Neutron Attenuation 21-4 References 22 Chapter 22: Water Potential: Piezometry 22-1 Introduction 22-2 Principles 22-3 Method of Installing Piezometers by Driving 22-3.1 Special Apparatus (Fig. 22-2) 22-3.2 Procedure 22-3.3 Comments 22-4 Method of Installing Piezometers by Jetting 22-4.1 Special Apparatus 22-4.2 Procedure 22-4.3 Comments 22-5 Method of Flushing and Testing Piezometers 22-5.1 Special Apparatus 22-5.2 Procedure 22-5.3 Comments 22-6 Method of Measuring Water Levels in Piezometers 22-6.1 Special Apparatus (Fig. 22-4) 22-6.2 Procedure 22-6.3 Comments 22-7 Method of Installing Tensiometers 22-7.1 Procedure 22-7.2 Comments 22-8 Interpretation of Hydraulic-Head Readings 22-9 References 23 Chapter 23: Water Potential: Tensiometry 23-1 Introduction 23-2 Principles 23-3 Field Tensiometry 23-3.1 Apparatus 23-3.2 Procedures 23-3.3 Applications 23-3.4 Comments 23-4 Laboratory Tensiometry 23-4.1 Apparatus 23-4.2. Procedures 23-4.3 Applications and Comments 23-5 References 24 Chapter 24: Water Potential: Thermocouple Psychrometry 24-1 Introduction 24-2 Principles of Operation 24-2.1 Temperature Fluctuations with Time 24-2.2. Temperature Gradients 24-2.3 Vapor Pressure Gradients 24-2.4 Wet Junction Characteristics 24-3 Methods 24-3.1 Apparatus 24-3.2 Calibration 24-3.3 Temperature Correction 24-3.4 Sample Preparation 24-3.5 Measuring Extremely Low Water Potentials 24-3.6 Separation of Osmotic and Matric Potential Components 24-4 Appendix 24-5 References 25 Chapter 25: Water Potential: Miscellaneous Methods 25-1 Introduction 25-2 Water Potential Measurements with Electrical Resistance Sensors 25-2.1 Principles 25-2.2 Apparatus 25-2.3 Calibration 25-2.4 Precautions and Errors 25-3 Water Potential Measurement with Heat Dissipation Sensors 25-3.1 Principles 25-3.2 Sensor Construction 25-3.3 Calibration Procedures 25-3.4 Installation 25-3.5 Measurement Techniques and Interpretation 25-3.6 Precautions and Errors 25-4 Water Potential Measurement Using the Filter Paper Technique 25-4.1 Principle 25-4.2 Measurement Procedure 25-4.3 Precautions and Errors 25-5 Water Potential Measurement Using Vapor Equilibration 25-5.1 Principle 25-5.2 Procedure 25-5.3 Precautions and Errors 25-6 References 26 Chapter 26: Water Retention: Laboratory Methods 26-1 General Principles 26-2 Samples 26-3 Wetting Fluid 26-4 Wetting of Samples 26-5 Temperature Effects 26-6 Method 26-6.1 Apparatus 26-6.2 Procedure 26-6.3 Calculations 26-7 Comments 26-7.1 Determination of Wetting Curves 26-7.2 Water Retention of Stony Soils 26-8 Other Methods 26-8.1 Weighable Cells 26-8.2 Suction Tables 26-8.3 High-Range Membrane Method 26-8.4 Psychrometer Method 26-8.5 Vapor Equilibrium Method 26-8.6 Osmotic Method 26-8.7 Null Method 26-8.8 Dynamic Methods 26-9 References 27 Chapter 27: Water Retention: Field Methods 27-1 Introduction 27-2 Principles 27-2.1 Site-related Considerations 27-2.2 Instrument-related Considerations 27-2.3 Nature and State of Soil Volume 27-3 Method 27-3.1 Method for 0 to -50 kPa Range 27-3.2. Method for Evapotranspiration Range of Potentials 27-4 Data Handling 27-4.1 Data Conversion 27-4.2 Smoothing θ(t), ψ(t) Data 27-4.3 Derivation of Simultaneous θ and ψ Values 27-4.4 Determining θ(ψ) for the Pedon 27-4.5 Mathematical Retention Functions 27-5 Error Analysis 27-6 Spatial Heterogeneity 27-6.1 Statistical Methods 27-6.2 Scaling 27-7 Comments 27-8 References 28 Chapter 28: Hydraulic Conductivity and Diffusivity: Laboratory Methods 28-1 Introduction 28-2 General Principles 28-3 Samples and Test Fluid 28-3.1 Samples 28-3.2 Test Fluid 28-3.3. Preparation of Deaerated Solution 28-4 Hydraulic Conductivity of Saturated Soils 28-4.1 Constant Head Method 28-4.2 Falling-Head Method 28-5 Conductivity and Diffusivity of Unsaturated Soils 28-5.1 Steady-state Head Control Method 28-5.2 Steady-state Flux Control Method 28-5.3 Nonsteady-state Boltzmann Transform Methods 28-5.4 Sorptivity Method 28-6 Alternative Methods 28-6.1 Instantaneous Profile Method 28-6.2 Inflow-outflow through a High-resistance Porous Plate 28-6.3 Unit-gradient Drainage Method 28-6.4 Parameter Identification Method 28-7 References 29 Chapter 29: Hydraulic Conductivity of Saturated Soils: Field Methods 29-1 Introduction 29-2 Shallow Water Table Methods 29-2.1 Auger-hole Method 29-2.2. Piezometer Method 29-2.3 Other Methods 29-3 Deep Water Table Methods 29-3.1 Double-tube Method 29-3.2 Shallow Well Pump-in Method 29-3.3 Other Methods 29-4 Comments 29-5 References 30 Chapter 30: Hydraulic Conductivity, Diffusivity, and Sorptivity of Unsaturated Soils: Field Methods 30-1 Introduction 30-2 Unsteady Drainage-Flux Method 30-2.1 Principles 30-2.2 Method 30-3 Simplified Unsteady Drainage-Flux Method 30-3.1 Principles 30-3.2 Method 30-4 Crust-Imposed Steady Flux Method 30-4.1 Principles 30-4.2 Method 30-5 Sprinkler-Imposed Steady Flux Method 30-5.1 Principles 30-5.2 Method 30-5.3 Comments 30-6 Sorptivity by Ponded Infiltration 30-6.1 Principles 30-6.2 Method 30-7 Sorptivity by Infiltration at Negative Matric Pressure 30-7.1 Principles 30- 7.2 Method 30-8 References 31 Chapter 31: Hydraulic Conductivity of Unsaturated Soils: Prediction and Formulas 31-1 Introduction 31-2 Theory and Computational Formulas 31-2.1 General Concepts 31-2.2 Empirical Forms for K(ψ) and K(θ) 31-2.3 Computation Based on Macroscopic Models 31-2.4 Computation of Relative Hydraulic Conductivity Based on Statistical Models 31-2.5 Hysteresis of the Hydraulic Conductivity 31-3 Recommendations 31-3.1 Case A 31-3.2 Case B 31.3.3 Case C 31.3.4 Case D 31-4 References 32 Chapter 32: Intake Rate: Cylinder Infiltrometer 32-1 Introduction 32-2 Principles 32-2.1 Time and Depth Effects 32-2.2 Restricting Surface Layers 32-2.3 Errors Due to Lateral Divergence of Flow 32-2.4 Other Sources of Error 32-3 Method 32-3.1 Construction 32-3.2 Single- and Double-Ring Infiltrometers 32-3.3 Installation 32-3.4. Water Supply, Constant Water Depth, and Infiltration Measurement 32-3.5 Seepage Meters 32-3.6 Variability and Number of Measurements 32-4 Comments 32-5 References 33 Chapter 33: Intake Rate: Sprinkler Infiltrometer 33-1 Introduction 33-2 Design Parameters 33-2.1 Rainfall Intermittency 33-3 Simulator Systems 33-3.1 Nozzle Systems 33-3.2 Drop-Former Systems 33-3.3 System Modifications 33-4 A Recommended Sprinkling Infiltration System 33-4.1 Apparatus 33-4.2 Equipment Suppliers 33-4.3 Procedure 33-4.4 Data Processing 33-5 Comments 33-5.1 North Central Regional Project 33-5.2 Evaluation of C-factor in USLE 33-6 Conclusions 33-7 References 34 Chapter 34: Intake Rate: Border and Furrow 34-1 Introduction 34-2 The Volume Balance Advance Method 34-2.1 Principles 34-2.2 Equipment 34-2.3 Procedures 34-2.4 Data Analysis 34-2.5 Comments 34-3 The Inflow-Outflow Method 34-3.1 Principles 34-3.2 Procedures 34-3.3 Data Analysis 34-3.4 Comments 34-4 Recirculating Flow Method 34-4.1 Principles 34-4.2 Equipment 34-4.3 Procedure 34-4.4 Data Analysis 34-4.5 Comments 34-5 References 35 Chapter 35: Evaporation from Bare Soil Measured with High Spatial Resolution 35-1 Introduction 35-2 First-Stage Evaporimeter Method 35-2.1 Principles 35-2.2 Method 35-3 Microlysimeter Method 35-3.1 Principles 35-3.2 Method 35-4 References 36 Chapter 36: Field Capacity and Available Water Capacity 36-1 General Information 36-2 Field Capacity 36-2.1 In Situ Field Capacity 36-2.2 Field Capacity Approximations 36-3 Container Capacity 36-3.1. Principle 36-3.2. Apparatus 36-3.3. Procedure 36-3.4. Comments 36-4 Permanent Wilting Point 36-4.1. Sunflower Method for Permanent Wilting Point (PWP) 36-4.2 Pressure Outflow Apparatus PWP Approximation 36-5 Available Water Capacity 36-5.1. Principle 36-5.2. Procedure 36-5.3. Comments 36-6 References 37 Chapter 37: Temperature 37-1 General Introduction 37-2 Kinds of Thermometers Used in Soils Work 37-2.1 Introduction 37-2.2 Mercury or Liquid-in-Glass Thermometers 37-2.3 Bimetallic Thermometers 37-2.4 Bourdon Thermometers 37-2.5 Electrical Resistance Thermometers 37-2.6 Thermocouples 37-3 Calibration of Thermometers 37-3.1 Introduction 37-3.2 Principles 37-3.3 Method 37-4 Field Measurements 37-4.1 Introduction 37-4.2 Methods 37-5 References 38 Chapter 38: Heat Capacity and Specific Heat 38-1 Introduction 38-2 Principles 38-3 Method 38-3.1 Special Apparatus 38-3.2 Procedure 38-3.3 Comments 38-4 References 39 Chapter 39: Thermal Conductivity and Diffusivity 39-1 General Introduction 39-2 General Principles 39-3 Thermal Conductivity 39-3.1 Introduction 39-3.2 Principles 39-3.3 Method 39-4 Thermal Diffusivity 39-4.1 Principles 39-4.2 Method 39-5 References 40 Chapter 40: Heat Flux 40-1 Introduction 40-2 Calorimetric Method 40-2.1 Principles 40-2.2 Procedure 40-2.3 Apparatus 40-2.4 Comments 40-3 The Gradient Method 40-3.1 Principles 40-3.2 Procedure 40-3.3 Apparatus 40-3.4 Comments 40-4 The Combination Method 40-4.1 Principles 40-4.2 Apparatus and Procedure 40-4.3 Comments 40-5 Soil Heat Flux Plate Method 40-5.1 Theoretical Basis 40-5.2 Apparatus 40-5.3 Calibration Procedure 40-5.4 Comments 40-6 Further Comments 40-7 References 41 Chapter 41: Heat of Immersion 41-1 Introduction 41-2 Principles 41-3 Method 41-3.1 Special Apparatus 41-3.2 Procedure 41-3.3 Comments 41-4 References 42 Chapter 42: Solute Content 42-1 Introduction 42-2 Collection of Soil Water Samples Using In Situ Samplers 42-2.1 Principles 42-2.2 Apparatus 42-2.3 Procedure 42-3 Measuring Soluble Salts With In Situ or Remote Monitors 42-3.1 Porous Matrix Sensors 42-3.2 Bulk Soil Electrical Conductivity Sensors 42-4 References 43 Chapter 43: Solute Diffusivity 43-1 Introduction: Solutes in Water 43-2 Diffusion Concepts 43-2.1 Fick's First Law (for Steady-state Diffusion) 43-2.2 Fick's Second Law (Transient State) 43-3 Steady-State Method 43-3.1 Principles 43-3.2 Apparatus 43-3.3 Procedure 43-3.4 Comments 43-4 Transient-State Methods 43-4.1 Principles 43-4.2 Apparatus for Linear Transient Measurements 43-4.3 Procedure for Linear Transient-state Measurements 43-4.4 Comments on Linear Transient-state Measurements 43-5 Radial Transient Conditions 43-6 General Comments 43-7 References 44 Chapter 44: Solute Dispersion Coefficients and Retardation Factors 44-1 Introduction 44-2 Theoretical Principles 44-2.1 Transport Equation 44-2.2 Boundary Conditions and Analytical Solutions 44-3 Experimental Principles 44-3.1 Special Apparatus 44-3.2 Experimental Procedure 44-4 Method I: Trial and Error 44-4.1 Principles, Procedure, and Example 44-4.2 Comments 44-5 Method II: From the Slope of an Effluent Curve 44-5.1 Principles 44-5.2 Procedure 44-5.3 Example 44-5.4 Comments 44-6 Method III: From a Log-Normal Plot of the Effluent Curve 44-6.1 Principles 44-6.2 Procedure 44-6.3 Example 44-6.4 Comments 44-7 Method IV: Least-Squares Analysis of the Effluent Curve 44-7.1 Principles 44-7.2 Comments 44-8 Method V: From Concentration-Distance Curves 44-9 Other Transport Models 44-10 General Comments 44-11 Appendix 44-12 References 45 Chapter 45: Water and Solute Flux 45-1 General Introduction 45-2 Water Flux 45-2.1 Soil Water Flux Meter 45-2.2 Water Content Method 45-3 Solute Flux 45-3.1 Average Concentration Method 45-3.2 Approximate Analytic Solution Method 45-3.3 A Model for Long-term Estimation of Solute Flux 45-3.4 Model for Short-term Estimation of Water and Solute Movement 45-4 Summary 45-5 References 46 Chapter 46: Gas Diffusivity 46-1 Introduction 46-2 Laboratory Method 46-2.1 Principles 46-2.2 Apparatus and Materials 46-2.3 Procedure 46-2.4 Comments 46-3 Field Method 46-3.1 Principles 46-3.2 Apparatus and Materials 46-3.3 Procedure 46-3.4 Comments 46-4 References 47 Chapter 47: Gas Flux 47-1 Introduction 47-2 Flux Calculated From Fick's Law 47-2.1 Principles 47-2.2 Apparatus and Materials 47-2.3 Procedure 47-2.4 Comments 47-3 Closed Chamber Method 47-3.1 Principles 47-3.2 Apparatus and Materials 47-3.3 Procedure 47-3.4 Comments 47-4 Flow-through Chamber Method 47-4.1 Principles 47-4.2 Apparatus and Materials 47-4.3 Procedure 47-4.4 Comments 47-5 Comments on Mechanisms Causing Mass Flow 47-6 References 48 Chapter 48: Air Permeability 48-1 Introduction 48-2 Principles 48-3 Methods 48-3.1 Unsteady-state Methods 48-3.2 Steady-state Methods 48-3.3 Other Steady-state Methods 48-4 Limitations 48-5 References 49 Chapter 49: Oxygen Electrode Measurement 49-1 Introduction 49-2 Platinum Electrode Method 49-2.1 Principles 49-2.3 Procedures 49-2.4 Comments 49-3 Membrane Electrode Method 49-3.1 Principles 49-3.2 Equipment 49-3.3 Procedures 49-3.4 Comments 49-4 References 50 Chapter 50: Air Pressure Measurement 50-1 Introduction 50-2 Principles 50-2.1 General 50-2.2 Measurement System Parameters 50-3 Methods 50-3.1 Instrument Construction 50-3.2 Installation and Operation 50-4 References 51 SUBJECT INDEX