Module 2 - Forestry and LiDAR

This week, in the second Applications in GIS lab, was about Forestry and LiDAR. 

    In this weeks module we applied GIS with Lidar in looking at an area of land with concerns to     Forestry. This lab utilized a lot of geoprocessing tools to get the values we wanted to reach from the provided data. I will give a bit of an explanation of the lab as I show you the maps I made.

    For this lab we retrieved the LiDAR data from the Virginia LiDAR application. This would be a chunk of land directly lifted from the Shenandoah National Park. From there, the retrieved .laz file would be converted into an .las file which you can see in the first part of map one. From there we wanted to calculate the forest height, so we changed the values of the .las file to get the ground and non ground put into a raster. These would be named DEM and DSM, which you can see one in the map one. From there we used minus tool to get the height file you see in the map two. We also later made a histogram to show the data on the trees. To clear up any confusion, value is the tree height.

Lidar and DEM, Map one

    For the next part of the lab was to get the densities of the canopy, this required quite a few tools. This started with making multi points for both ground and vegetation from the .las file. Then we changed the files to rasters and then began changing and adding data to them. We used the Is Null tool to change any values that were not null to one and then con tool to make the data recall the ground raster if there was a value that wasn't zero. We then added the files together with the plus tool and also made sure it could use float data. Lastly, we divided the float derived data from the con tool made count vegetation. This then resulted in the densities map you see in the second map. 

Tree Heights and graph, as well as Canopy Densities, Map two

With this lab done I feel a sense of accomplishment in the work I had done and also the lesson overall. Although there was some hiccups with ArcGIS and messing with LiDAR, I think the lab taught a lot. I am eager to see what the next lab brings. 

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