processing lidar data: fusion tutorial - cif-ifc · 3 lidar data used in this tutorial discrete...
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Processing LiDAR data:
Fusion tutorial
Douglas Bolton Rory Tooke
Nicholas Coops
University of British Columbia
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• Open/Visualize LiDAR data in Fusion
• Derive surface products (2 m) - Digital elevation model (DEM)
- Digital surface model (DSM)
- Canopy height model (CHM)
• Extract LiDAR data for polygons and plots - Calculate LiDAR metrics for plots
• Calculate gridded LiDAR metrics - Apply existing models in ArcGIS to derive biomass, volume, etc. from
gridded metrics
• Learn to work with multiple LiDAR tiles
Tutorial Objectives
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LiDAR data used in this tutorial
Discrete return LiDAR data collected in 2010 over the Malcolm Knapp Research Forest
- Collected by McElhanney Consulting Services Ltd using a ALS50-II Leica system
- Average of 3.1 pulses/m2
- Multiple returns per pulse
- Aerial photos were collected on the same flight
Malcolm Knapp Research Forest - UBC Research Forest
- Located in the Coast Western Hemlock biogeoclimatic subzone near Maple Ridge, BC
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• Open/Visualize LiDAR data in Fusion
• Derive surface products (2 m) - Digital elevation model (DEM)
- Digital surface model (DSM)
- Canopy height model (CHM)
• Extract LiDAR data for polygons and plots - Calculate LiDAR metrics for plots
• Calculate gridded LiDAR metrics - Apply existing models in ArcGIS to derive biomass, volume, etc. from
gridded metrics
• Learn to work with multiple LiDAR tiles
Tutorial Objectives
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Step 1: Extract probable ground returns (Groundfilter)
Step 2: Create surface from ground returns (GridSurfaceCreate)
Lidar visualizations produced with FUSION/LDA software – USDA Forest Service
Digital Elevation Model (DEM)
6 6 Lidar visualizations produced with FUSION/LDA software – USDA Forest Service
Digital Surface Model (DSM)
Create a digital surface model (CanopyModel)
7 7 Lidar visualizations produced with FUSION/LDA software – USDA Forest Service
Digital Surface Model (DSM)
Create a digital surface model (CanopyModel)
8 8 Lidar visualizations produced with FUSION/LDA software – USDA Forest Service
Digital Surface Model (DSM)
Create a digital surface model (CanopyModel)
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Visualization for
Malcolm Knapp Research Forest
Digital Surface Model (DSM)
Create a digital surface model (CanopyModel)
10 Lidar visualizations produced with FUSION/LDA software – USDA Forest Service
Digital Surface Model (DSM)
Create a digital surface model (CanopyModel)
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Height (m)
Point
elevation
Surface
elevation
Point
height above
surface
Lidar visualizations produced with FUSION/LDA software – USDA Forest Service
Canopy Height Model (CHM)
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Height (m)
Lidar visualizations produced with FUSION/LDA software – USDA Forest Service
33.0 m 35.9 m
34.4 m 35.6 m 40.7 m
34.8 m
Canopy Height Model (CHM)
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Lidar Point Cloud for Alex Fraser Research Forest
Lidar visualizations produced with FUSION/LDA software – USDA Forest Service
Plot level analysis
Extract LiDAR data for plots (Clipdata)
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Lidar Point Cloud for Alex Fraser Research Forest
Plot level analysis
Extract LiDAR data for plots (Clipdata)
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High Volume Site Low Volume Site
Hei
ght
(m)
86% 16%
Calculate Cover Metrics
Cover Above 2 m
Calculating Lidar metrics
Calculate metrics (Cloudmetrics)
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High Volume Site Low Volume Site
Hei
ght
(m)
27 m 15.6 m
Calculate Height Metrics
Mean Height
Calculating Lidar metrics
Calculate metrics (Cloudmetrics)
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High Volume Site Low Volume Site
Hei
ght
(m)
30 m 21 m
Calculate Height Metrics
75th Percentile
Calculating Lidar metrics
Calculate metrics (Cloudmetrics)
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High Volume Site Low Volume Site
Hei
ght
(m)
33.5 m 29 m
Calculate Height Metrics
95th Percentile
Calculating Lidar metrics
Calculate metrics (Cloudmetrics)
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High Volume Site Low Volume Site
Hei
ght
(m)
0.19 m 0.50 m
Coefficient of Variation
Measure of the structural diversity
Calculating Lidar metrics
Calculate metrics (Cloudmetrics)
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Plot Level Analysis
Forest Attributes Gross Stem Volume Basal Area Mean height Dominant height Loreys height Wood biomass Bark biomass Stem biomass Foliage biomass Branches biomass Crown biomass Total above-ground biomass
Lidar Metrics 75th height percentile 95th height percentile Mean Standard deviation Coefficient of variation Cover above 2 meters
Linear model
Forest Attribute = exp(b0 + b1ln(x1) + b2ln(x2)…bnln(xn)