(section 09) mock Exam

Question 1

Exercise 1 (3.0 points)
There are two riverside areas, which are suitable for the construction of a new retention
basin. Both areas are defined by their vertices (dt. Eckpunkte). The vertices of area 1 are
given in the shapefile “area_1.shp”. But the vertices of the second area are only available in
a table format (area_2.dbf).

Question 2

Exercise 1.1 (2.25 points)
Create a new shapefile called “retention_areas.shp” and digitize both areas. One of the
area’s borders runs adjacent to the river and follows its shape. The others can be digitized as
straight lines.
Make sure that you combine both areas in one shapefile.

Answer 2

Approach:

• Create a new shapefile
• Digitize area 1
• Add vertices of area 2 (Hint: Use the snapping tool)
• Digitize area 2
• Put both areas into one shapefile (Hint: Union)

Question 3

Exercise 1.2 (0.75 points)
In order to distinguish both areas, make sure you add the attributes “area_1” and “area_2” to
the attribute table.

Answer 3

Approach:
- Add a new column to the attribute table for the distinguishing attribute (Hint: don’t
forget to choose type ‘Text’)
- Add the attributes
- Add a new column to the attribute for the area (in m²)
- Calculate the area in m² (Hint: Field calculator)

Question 4

Exercise 2 (9.5 points)
In order to determine the most suitable area, you’ve discussed the project with one of your
senior colleagues. She tells you that the following factors are important for a later discussion
with current owners and the constructive planning:
1) Total size of the area
2) Land use
3) Slope conditions
Hint: In case you did not solve exercise 1, please use the shapefiles Area1_preset and Area2_preset
found under vectordata.

Question 5

Exercise 2.1 (1.0 points)

Calculate the total size for both areas as an integer in the attribute table. (Use m²)

Answer 5

Approach:

• Bring the two areas together (Hint: Dissolve)
• Recalculate the new area (Hint: Field calculator)

Question 6

Exercise 2.2 (6.25 points)
Calculate the total area per land use for both areas as an integer number. Use m² as unit.
Display your outcome in one pie chart per area. Your pie charts should get a legend and a
header defining the belonging area. Save your graphs as JPEGs in your folder.

Answer 6

Approach:
- Intersect land use and retention basin areas
- Select one retention area and dissolve area by OBART
(Hint: make sure to tick “Selected features only” and choose the “Dissolve field”
OBART)
- Add a new column to the attribute table of the dissolved area
- Calculate the areas
- Create a pie chart and save it as *.jpg (Hint: Use DataPlotly)
- Repeat steps for the other retention area

Question 7

Exercise 2.3 (2.25 points)
Identify the sections with a slope less than two percent, for both areas.
Your z-factor is 0,01.

Answer 7

Approach:
- Clip Raster by Mask Layer (Hint: Input Layer = dem_Waldfeucht, Mask Layer = Both
retention basin areas)
- Convert the clipped DEM to a Slope layer (Hint: Raster terrain analysis →Slope ,
Make sure to use the right z-factor)
- Use the Raster calculator to create a layer with a slope less than two percent
- Distinguish the areas with a slope less than two percent from areas with more than
two percent by using the symbology

Question 8

Exercise 3 (5.0 points)
In a final meeting, both areas will be evaluated based on your GIS-research. Therefore, you
have to present your results in an illustrative map. You decide to create a map in A3
landscape format using QGIS.
The following results are relevant to your presentation:
1. General view of the municipality Waldfeucht including the two highlighted areas and
the rivers
2. Detailed view of the two areas showing their land use in its correct symbology
a. Both areas should be labelled with their size
b. There should be a legend declaring the land uses colouring
3. The pie charts showing the distribution of land use in the respective areas
4. Detailed view of the two areas showing the parts with a slope less than two percent
including a legend
5. There should also be a north arrow, scale bar, title, and the author’s name in your
map

Answer 8

Approach:
- Create a new print Layout
- Add all the necessary maps and items and display them in an understanding way
(Hint: You can take the example picture as a reference)
- Remember: The pie charts are implemented as pictures and you have most influence
on their appearance while creating them in DataPlotly