Terrain Analysis in QGIS

Terrain Analysis is the interpretation of topographic features through Geographic Information Systems (GIS).

Such features include Slope, Aspect, Viewshed, Elevation, Contour lines, flow, up-slope flow lines, and down-slope flow lines. It is relationships between ecological processes and physical features.

Terrain is a involves the vertical and horizontal dimensions of land surface. Terrain data are often used as a component in complex GIS modeling or classification routines. They can, for example, be a key to identifying wildlife habitats that are associated with specific elevations. Slope and aspect images are often an important factor in assessing the suitability of a site for a proposed use. Terrain data can also be used for vegetation classification based on species that are terrain-sensitive.

In this Tutorial, use Terrain Analysis tools to find out more information about the surface.

First Add the Data (DEM). click Raster, go to your folder, select data and click OK.

Go to Raster > Terrain Analysis and select the Terrain model.

Perform 6 Terrain Analysis model using QGIS Software.

1. Slope
2. Aspect
3. Hillshade
4. Relief
5. Ruggedness Index
6. Contour

Slope

Open Slope, Slope window is appears, select Elevation layer and Output layer, Output format default GeoTIFF is OK, Type Z factor (300) and click OK.

(Z factor- Difference between Horizontal and Vertical Height).

Now you can change slope properties or customize the slope. Right click slope layer and select properties.

Aspect

Open Aspect, Aspect window is appears, select Elevation layer and Output layer, Output format default GeoTIFF is OK, Type Z factor (300) and click OK.

Hillshade

Open Hillshade, Hillshade window is appears, select Elevation layer and Output layer, Output format default GeoTIFF is OK, Type Z factor (300). you’ll also change Azimuth and Angle and click OK.

Relief

Open Relief, Relief window is appears, select Elevation layer and Output layer, Output format default GeoTIFF is OK, Type Z factor (300) and click OK.

Ruggedness Index

Open Ruggedness, Ruggedness window is appears, select Elevation layer and Output layer, Output format default GeoTIFF is OK, Type Z factor (300) and click OK.

Contour

Perform Contour, select Raster > Extraction and click contour. Open Contour, Contour window is appears, Select Input file and Output file, Input contour interval (100) and click OK.