Module 2: Forestry and LiDAR

    In this week's lab, I worked with LiDAR data and generated several useful layers including: a digital elevation model (DEM), digital surface model (DSM), tree height, and canopy density layer. Below is a copy of the LiDAR layer and DEM output.

    Throughout the assignment, it quickly became apparent that these layers were very large and easily bogged down ArcGIS Pro. To save time and to navigate in the map view better. I unselected layers as they were processed. Despite this, I still had issues writing the LiDAR layer in the layout, so I had to adjust the extent of the map. Overall the assignment this week introduced me to several new tools (LAS Dataset to Raster and  LAS to MultiPoint) that can be used to extract information from 3D layers including: elevation and canopy height. From there we used that information to generate vegetation height and canopy density layers. 

    Generating the vegetation height layer was straightforward; the values of the DEM layer were subtracted from the DSM layer. The difference was an approximate value for vegetation height. A histogram displaying vegetation height distribution was also generated to gain better insight about the forest of interest. See the output below. 

    Deriving canopy density was a bit more complicated; I started by creating ground and vegetation point layers. Then, I converted those into rasters that I could separate the ground and vegetation from the other categories in the LiDAR. After separating out the unnecessary pixels, the raster layers for ground and vegetation were added together. Last the vegetation raster was divided by the combined ground and vegetation raster to generate an approximate canopy density. See the output below.