Fig 1.
Location of study area consisting of forest management blocks (identified by number) across the Upper Goulburn and Thomson water supply protection areas.
Fig 2.
Elevation range in metres above sea level (mASL) for the LiDAR 1m DEM, VicMap Elevation DTM and SRTM DEM (left) and the difference in elevation between LiDAR 1m DEM and the VicMap Elevation DTM (LiDAR 1m-DTM) and SRTM DEM (LiDAR 1m-SRTM).
Fig 3.
Slope range in degrees for the LiDAR 1m DEM, VicMap Elevation DTM and SRTM DEM (left) and the difference in slope between LiDAR 1m DEM and the VicMap Elevation DTM (LiDAR 1m-DTM) and SRTM DEM (LiDAR 1m-SRTM).
Table 1.
Cutbblocks calculated with slopes >30° logged across the Upper Goulburn and Thomson Catchments using LiDAR at 1 m resolution (LiDAR 1m), LiDAR with a 5m (LiDAR F5m) average slope neighbourhood, the Shuttle Topography Radar Mission (STRM) at a 1 arc second resolution and the VicMap Elevation DTM (DTM) at 10m resolution.
Fig 4.
Comparison between areas >30° across cutblocks as calculated under LiDAR 1m, LiDAR F5m, VicMap Elevation DTM and SRTM DEM slope rasters.
Fig 5.
Comparison of slopes logged across forest management blocks across the Upper Goulburn and Thomson water supply protection areas.
Fig 6.
Percent of cut block area >30° in slope across Block 318 calculated using the LiDAR 1m DEM (A), the 5 m average slope calculated using the LiDAR DEM (LiDAR F5m) (B), calculated using the VicMap Elevation DTM (C) and calculated using the SRTM DEM (D).
Table 2.
Cutblocks calculated with slopes >30° logged across Block 318 using LiDAR at 1 m resolution, LiDAR with a 5m (LiDAR F5m) average slope neighbourhood, the Shuttle Topography Radar Mission (STRM 1 arc sec) at a 1 arc second resolution and the VicMap Elevation DTM (VicMap DTM) at 10m resolution.
Fig 7.
Comparison of slope calculations for Cutblock 318-512-0009 and 318-512-0010.
LiDAR derived slope at 1m resolution (Fig 7A); LiDAR derived slope with an average slope neighbourhood radius of 5m (Fig 7B); STRM derived slope at 1 arc second resolution (Fig 7C); DTM derived slope at 10m resolution (Fig 7D). Blue and Red lines show measured transects for the ANU and OCR Transects, respectively. Slope cross sections A and B are shown.
Fig 8.
Comparison slope calculations with transects measured on Cutblock 320-501-0024 by the Timber Harvest Compliance Unit of the OCR.
LiDAR derived slope at 1m resolution (Fig 8A); LiDAR derived slope with an average slope neighbourhood radius of 5m (Fig 8B); STRM derived slope at 1 arc second resolution (Fig 8C); DTM derived slope at 10m resolution (Fig 8D).
Fig 9.
Boxplots of transect measurements compared with slope rasters derived from LiDAR 1m Dem, VicMap Elevation DTM and SRTM DEM.
Fig 10.
Slope comparisons along transects across the area of Cutblock 318-512-0009 (left) and the Cutblock 318-512-0010 (right).
Table 3.
Sample of cutblocks calculated with slopes >30° logged using LiDAR at 1 m resolution (LiDAR 1m), LiDAR with a 5m (LiDAR F5m) average slope neighbourhood, the Shuttle Topography Radar Mission (STRM) at a 1 arc second resolution, and the VicMap Elevation DTM (DTM) at 10m resolution.
These cutblocks were measured by the authors and also by staff from the OCR.