Table of Contents
1 Introduction 1
1.1 This Book 1
1.2 What Measurements are Considered? 2
1.3 Scale of Measurement 3
2 Measurements 5
2.1 Measuring Things 5
2.2 Accuracy 5
2.3 Bias 7
2.4 Precision 8
2.5 Bias, Precision and the Value of Measurements 8
3 Stem Diameter 11
3.1 Basis of Diameter Measurement 11
3.2 Stem Cross-Sectional Shape 12
3.3 Measuring Stem Diameter 13
3.4 Tree Irregularities 14
3.5 Bark Thickness 15
4 Tree Height 17
4.1 Basis of Height Measurement 17
4.2 Height by Direct Methods 18
4.3 Height by Trigonometric Methods 18
4.4 Height by Geometric Methods 20
5 Stem Volume 23
5.1 Reasons for Volume Measurement 23
5.2 'Exact' Volume Measurement 24
5.3 Volume by Sectional Measurement 25
5.3.1 Sectional Volume Formulae 26
5.3.2 Tree Stem Shape 27
5.3.3 Sectional Measurement of Felled Trees 28
5.3.4 Sectional Measurement of Standing Trees 29
5.4 Volume by Importance or Centroid Sampling 30
6 Stem Volume and Taper Functions 33
6.1 The Functions 33
6.2 Volume Functions 33
6.2.1 Volume from Diameter and Height 34
6.2.2 Volume from Diameter, Height and Taper 36
6.2.3 Merchantable Stem Volume 38
6.3 Taper Functions 39
6.3.1 Examples of Taper Functions 39
6.3.2 Using Taper Functions 41
7 Biomass 47
7.1 Reasons for Biomass Measurement 47
7.2 Measuring Biomass 47
7.2.1 Branches and Foliage 48
7.2.2 Stems 50
7.2.3 Roots 50
7.2.4 Carbon Content of Biomass 52
7.3 Above-Ground Biomass Estimation Functions 52
7.4 Biomass Estimation Functions for Tree Parts 58
7.4.1 Allometric Functions 59
7.4.2 Biomass Expansion Factors 60
7.4.3 Leaves 61
7.4.4 Roots 63
8 Stand Measurement 65
8.1 Stands and Why They areMeasured 65
8.2 Measurements Taken in Stands 65
8.3 Age 66
8.4 Basal Area 67
8.4.1 Plot Measurement 68
8.4.2 Point Sampling 68
8.4.3 Plot Measurement Versus Point Sampling 71
8.4.4 Practicalities of Point Sampling 72
8.5 Stocking Density 73
8.6 Quadratic Mean Diameter 74
8.7 Dominant Height 75
8.7.1 Importance of Dominant Height 75
8.7.2 Measuring Dominant Height 76
8.8 Site Productive Capacity 77
8.9 Volume 80
8.9.1 Plot Measurement 80
8.9.2 Point Sampling 81
8.10 Biomass 82
8.10.1 Root Biomass 82
8.10.2 Fine Root Biomass and Area 84
8.10.3 Precision of Biomass Estimates 85
8.11 Stand Growth 86
9 Measuring Populations 91
9.1 Forest Inventory and Sampling 91
9.2 Subjective Versus Objective Sample Selection 92
9.3 Population Statistics 93
9.3.1 Measures of Central Tendency 93
9.3.2 Variance and Confidence Limits 93
9.4 Calculating the Population Statistics 94
10 Sampling Theory 99
10.1 Sampling Techniques and Their Efficiency 99
10.2 Sampling with Varying Probability of Selection 99
10.2.1 The Population Mean and Its Variance 100
10.2.2 Probability Proportional to Size 101
10.2.3 Probability Proportional to Prediction 103
10.3 Stratified Random Sampling 106
10.4 Model-based Sampling 108
10.4.1 Applying Model-Based Sampling 109
10.5 Choosing the Sampling Technique 112
11 Conducting an Inventory 115
11.1 Objectives 115
11.2 Approach and Methods 116
11.3 Forest Area 117
11.4 Sampling Units and Calculation of Results 118
11.5 Systematic Sampling 120
11.6 Stand Measurement 121
11.6.1 Shape 121
11.6.2 Positioning 121
11.6.3 Size 122
11.6.4 Edge Plots 123
11.7 Measurement Errors 123
11.8 More Advanced Inventory 124
12 The Plane Survey 125
12.1 Mapping 125
12.2 Survey Example 126
12.3 Conducting the Survey 126
12.4 Calculating the Survey Results 129
12.5 Area of a Surveyed Region 131
12.6 Global Positioning System 133
13 Remote Sensing 135
13.1 Ground Measurement 135
13.1.1 Tree Stems and Crowns Using Lasers 136
13.1.2 Leaf Area Index Using Sunlight 139
13.1.3 Roots 141
13.2 Airborne Measurement 143
13.2.1 Aerial Photography 144
13.2.2 Laser Scanning 146
13.2.3 Spectrometry 148
13.3 Satellites 149
References 153
Appendix A 171
Appendix B 179
Appendix C 181
Appendix D 183
Index 185
