| dc.description.abstract | Terrestrial laser scanning data acquired from 55 sample plots (32 m × 32 m) in Evo, Southern Finland during April 22 to May 14, 2024 (leaf-off conditions) using a Riegl VZ-400i terrestrial laser scanner with following configuration:
Acquisition Dates: 22 April – 14 May 2024
Conditions: Leaf-off
Scanner Model: Riegl VZ-400i
Measurement principle: Time-of-flight
Wavelength: 1550 nm
Laser Beam Diameter (at exit): 7 mm
Beam Divergence: 0.35 mrad (at the 1/e² points)
Beam Diameter at 10, 20 and 30 m: 10, 14, 18 mm
Pulse Repetition Rate: 600 kHz
Maximum Returns per Pulse: Up to 8
Scan Pattern: ‘Panorama 40’
Angular Resolution: 0.04°
Point Spacing at 10 m: 3.5 mm
Vertical Field of View: 100° (Scan Position, upright), 360° (Scanner tilted 90°)
Horizontal Field of View: 360° (Scan Position, upright), 100° (Scanner tilted 90°)
The data was processed in the RiSCAN PRO software (version 2.19.3) where the built-in LIS TreeAnalyzer plugin, developed by Laserdata GmbH, was utilized for identifying and segmenting individual trees and measuring their characteristics.
For each sample plot (n = 55), a point cloud file (.laz) is provided with the following attributes for each point record:
- X coordinate (Easting) [m], ETRS-TM35FIN (epsg: 3067)
- Y coordinate (Northing) [m], ETRS-TM35FIN (epsg: 3067)
- Z coordinate (Height) [m], N2000
- Reflectance (distance-corrected intensity) [dB]
- Return number
- Return count
- Point Cloud ID (scan position ID)
- Height above ground level [m]
- Tree ID number
In addition, a text file is provided, containing the following attributes for each segmented tree (n = 6320):
- X coordinate of stem cross section mid-point (Easting) [m], ETRS-TM35FIN (epsg: 3067)
- Y coordinate of stem cross section mid-point (Northing) [m], ETRS-TM35FIN (epsg: 3067)
- Z coordinate of stem cross section height [m], N2000
- Sample plot ID number
- Tree ID number
- Circle completeness (related to Hough circle finding for tree identification)
- Crown projection area [m2]
- Crown diameter [m]
- Stem diameter measured at the height of tree identification [m]
- Goodness of fit (related to Hough circle finding for tree identification)
- Height of the point cloud slice used for tree identification [m] | |
