Module 2: Forestry and LiDAR

This week we focused on LiDAR applications in forestry. Utilizing a .las point file of the Shenandoah National Park, downloaded from the Virginia Lidar application, we determined the height, density, and elevation of the forest area in grid N16_5807_20.

First, we created a DEM and DSM file in order to subtract the two files and determine the height of the forest. Here the DEM was the ground points, the DSM the non-ground points, and we used the MINUS tool to determine the height. Using the height file, I also created a chart to visualize the tree height distribution.

Secondly, we determined the biomass density of the forest. First, we converted the Ground and Vegetation LAS files to multipoint, and then to raster via the Point to Raster tool. Then we made the raster binary files, pulled from the original LAS files where the criteria were false, combined both the ground and vegetation files, and lastly divided the count file by the raster file.

Below are the original Lidar file and the DEM file we created.

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