Module 2 - Forestry and Lidar

In this week's module, we explored .laz and .las lidar data files, and we generated Digital Elevation Models (DEMs) and Digital Surface Models (DSMs) from lidar data. Additionally, we computed forest height and assessed biomass density.

Initially, I retrieved the data from the Virginia Lidar application and employed the convert LAS tool to transform the downloaded .laz file into a .las file.

Subsequently, I calculated the forest height. To begin, I utilized the Point File Information tool, which produces statistical data regarding the .las layer, including the number of points, as well as the maximum, minimum, and average point spacing.

Following this, I created a DEM layer from the lidar ground point layer by using the LAS Dataset to Raster tool. Furthermore, I generated a DSM layer for the non-ground points. Furthermore, the Minus tool is used to subtract the ground height from the non-ground height in order to determine the tree height.

In the final step to calculate biomass density, I utilized a combination of tools, specifically: the LAS to MultiPoint tool, setting Class code 2 for bare earth and 1 for vegetation; the Point to Raster tool to convert the two new layers into raster format; the IS Null tool to create binary files; the Con tool to assign a value of 0 to true raster and to pull false values from the original raster; the Plus tool to merge both layers from the previous step; and the Float tool to convert the Plus result from integer to float. Finally, we applied the Divide tool to compute the density.