Have you ever wondered how LiDAR and radar are used to map and preserve natural resources like forests? These two technologies are key tools in the realm of geo-information science, and they have several applications in natural resource management. In this article, we will take a closer look at how LiDAR and radar work and how they're used to map and monitor forests.
Development
LiDAR stands for "Light Detection and Ranging." It works by emitting a laser beam and measuring the time it takes for it to bounce back after it hits an object. By measuring the time it takes for the laser beam to return to the sensor, LiDARs can calculate the distance to an object and create a 3D map of the surroundings. One of the key ways that LiDAR is used in geo-information science is to measure the height of trees in forests. By measuring the distance between the LiDAR sensor and the tops of the trees, researchers can create a map of a forest's structure. This information is useful for several purposes, such as estimating the amount of carbon stored in the forest and assessing the impact of natural disasters or human disturbances, such as deforestation.
Radar stands for "Radio Detection and Ranging." It works by emitting a radio or microwave and, like LiDAR, it can be used to create 3D information of the Earth under certain conditions. The main difference between the two is the type of radiation that they use: radar uses radio or microwaves, while LiDAR uses lasers mostly in the near-infrared domain. In addition, radars can be imaging systems, where the radar backscatter can be also used to retrieve information about forest structure. LiDAR is generally more accurate in the estimation of forest height and stored carbon, and can produce higher resolution data; radar, on the other hand, is less accurate, but it is also less expensive and can operate in wider conditions. Both technologies are often used together to produce the most accurate results.
Assistant Professor Michael Schlund, at the ITC Faculty’s NRS department, has conducted research using radar and LiDAR. You can read some of his publications on these topics here and here.
