Watershed Analysis in QGIS

This video tutorial guides users through accessing the Lake Vic fish dataverse to download a digital elevation model (DEM) file. It then demonstrates how to load the DEM into QGIS, install the OpenLayers plugin, and adjust the transparency of the DEM layer. The tutorial concludes with a step-by-step process for conducting a watershed analysis using GRASS commands in QGIS.

What is the first step in accessing the Lake Victoria DEM data?

• Open QGIS and add a new layer

• Search for the DEM in the Lake Vic fish dataverse

• Download the OpenLayers plugin

• Adjust the transparency settings

After downloading the DEM file, what is the next step in QGIS?

• Install the OpenLayers plugin

• Adjust the transparency of the DEM layer

• Add the DEM file as raster data

• Perform watershed analysis

What should you do if the OpenLayers plugin is not installed?

• Download a different DEM file

• Search for it under the 'not installed' tab and install it

• Adjust the transparency settings

• Perform watershed analysis

How can you view the DEM layer on top of the OpenStreetMap layer?

• By turning off the OpenStreetMap layer

• By dragging the DEM layer to the bottom

• By zooming in on the OpenStreetMap layer

• By increasing the transparency of the DEM layer

What is the purpose of adjusting the transparency of the DEM layer?

• To perform watershed analysis

• To enhance the color of the DEM layer

• To see the OpenStreetMap layer underneath

• To make the DEM layer invisible

Which tool in the processing toolbox is used for watershed analysis?

• DEM layer properties

• Transparency settings

• OpenLayers plugin

• Watershed under GRASS 7 commands

What should be done with the output files after running the watershed tool?

• Open them immediately

• Save them with descriptive names

• Delete unnecessary files

• Share them online

What is the minimum size of the exterior watershed basin set to during analysis?

• 200

• 150

• 100

• 50

What is the last step before running the watershed tool?

• Download the DEM file

• Install the OpenLayers plugin

• Adjust transparency settings

• Enable single flow direction

What is the final step after creating the output files in the watershed analysis?

• Install additional plugins

• Adjust the transparency settings

• Turn off the DEM layer

• Prepare for the next part of the exercise