Forestry and LiDAR

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LiDAR, or light detection and ranging, is a common technology used in remote sensing. Aerial LiDAR systems mounted on aircraft or satellites send pulses of laser light to the surface of the Earth, and the reflected energy is recorded. When used over vegetation, LiDAR signals will typically return multiple values representing the top of the canopy and the ground. These values can be used by foresters, scientists, and other natural resource professionals to calculate variables such as canopy height, canopy density, and canopy structure. 

In this lab, our task was to create layers showing canopy density and tree height with LiDAR data from a small section of the Shenandoah National Park in Virginia. This data was originally captured by the U.S. Geological Survey. The first step was to convert the ground and vegetation data from point cloud (.las) to raster, using a multipoint layer as an intermediary step. We then used these rasters in conjunction with several other geoprocessing tools to derive layers for canopy density and tree height. Below are my results showing the original LiDAR data, a digital elevation model (DEM), a canopy density layer, and tree height layer. There is also a graph at the bottom showing the distribution for tree height. 





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