LiDAR

This week we played with LiDAR data to analyze the tree canopy in portion of the Shenandoah National Park. I was very excited to play with this data as I hope to use it as an important tool in some of my archaeological research. I've learned that LiDAR data is amazing but very slow and clunky in ArcGIS. I'm used to working with large datasets of 3D point clouds, but the manipulation of this data in GIS is very different than in the other programs I've used. And it takes time to process and even to draw the data for visualization. Important things to keep in mind as I start my LiDAR journey.

We used the data to look at a few different things for the area. The first was creating a digital elevation model (DEM) and a digital surface model (DSM). To do this, we filtered the points classed as ground surface (DEM) and those classified as non-ground (DSM). 

Next we looked at the height of the trees by comparing the vegetation height of the DSM to the ground heights of the DEM.

Finally, we calculated the canopy density by converting the ground and vegetation points into raster files and using several tools to categorize the pixels and compare the two datasets.