Wenita has joined a group of local forest companies to commission a LiDAR survey over forests in Otago. Participating companies also include City Forests, Ernslaw One, Rayonier and Port Blakely.
LiDAR is an acronym for “light detection and ranging” and is sometimes alternatively called ALS for “airborne laser scanning” when used for surveying landscapes. LiDAR is also used in some autonomous vehicles, which use the technology for sensing their environment. LiDAR scanners fire out up to a million laser pulses per second and detect the laser light bouncing back to the instrument. When combined with a very accurate GPS location of the sensor and the angle and distance of the laser returns, a “point cloud” of reflecting surfaces can be computed (see image).
LiDAR in forestry allows a very accurate digital terrain model (DTM) to be calculated, even when the ground is obscured by the standing trees. It also allows accurate measurement of tree heights that, with repeated surveys, enables growth rates to be calculated.