Laser-carrying drones that can see through the forest canopy are being used to protect native plants threatened by invasive species.
The drones use Lidar (light detection and ranging), which works like radar but uses light instead of radio waves. Laser pulses are fired at the trees below and the time it takes for wavelengths to bounce back is used to create a 3D picture of what lies beneath. The data is combined with information from satellites to give an accurate "fix" of the drone's position.
It all builds up an accurate map of the health of the forest floor.
Lidar has been used from the air before but typically this has been from larger aircraft with humans on board. An unmanned aerial vehicle (UAV), usually known as a drone, holds out the prospect of reduced cost. The point of the project is to monitor and map how land use is changing and how climate change is affecting Malaysia's forests. Conventional photos taken in natural light will only show the tree canopy.
Lidar drone covers a much smaller area with each sweep but the resolution is "an order of magnitude better".One key emphasis is on protecting native species - and fighting one non-native threat in particular. They carry a fungal disease that harms trees and their leaf litter is toxic to native plants. Without Lidar the bushes can spread undetected.
