Data: Herberg Memorial Forest lidar data in *.las format. In folder "Proclaser"
Software: ArcMap 10.3.1
Spatial reference: WGS_1984_UTM_zone_18N
Create LAS dataset
Las dataset is different from Las file in ArcMap
Build DEM and DSM
1. filter
ALL:
Ground: used to generated DEM
Non-ground: used for statistics
First: used to generate DSM
Projection
When creating LAS dataset, the XY Coordinate system needs to be set to unknown in order to match with plots data. I think the default coordinate system is not correct. If the coordinate system is set to others beside unknown, it can not match with plot data. In the meantime, the extent of LAS dataset will change in N-S direction.
For now, I can not find a way to correct this problem. Therefore, I will leave the coordinate system in the unknown status.
Plot statistics
For each plot:
1. Buffer with distance 11.35 m (circular plot with the radius of 11.35 m).
2. Add LAS tools to ArcToolBox
Download link: https://rapidlasso.com/lastools/
3. ArcToolBox -- LAStools -- lasClip
The toolbox needs to install in a directory name without spaces.
When specifying the output file location, name the file with .las.
4. Calculation of lidar metrics
The results I got from FUSION is similar to these from LAStools.
To see:
http://www.cs.unc.edu/~isenburg/lastools/download/lascanopy_README.txt
