Population dot density in Context

“Population distribution describes a way in which people are spread across the earth surface. Population distribution is usually shown by a dot density map where each dot represent a certain number of ”

In this module, we will learn how to create a dot density map.

You try:

Goal: Create a dot density map where 1 dot represents 1000 people.

Data: Sample data: local-data-district.shp, kzn_population.csv

  • Load the layers into a new project.
  • Right-click on districts and choose properties.
  • Select the join tab and create a join. Use the join field.
  • Create a join using the specified join columns.
  • Select which fields to join to. ( select area_km,population_2016,density)
  • Activate custom field name prefix and give an appropriate name.
  • Right-click on district layer and choose 'Save As'.
  • Change the CRS to the specified one and proceed to save the layer. Make sure the name corresponds to new layer.
  • Use the spatial algorithm to create the random points using the district_hbk layer.
  • Symbolise the resultant point layer and create a legend that shows your results.

Name Expectation

CRS

South African CRS : HBK_NO_29

Join column

District:code

Spatial algorithm

Random Points

New layer

district_hbk

More about

Dot density maps are effective at showing density variations on geographic landscapes.
Dot maps are advantageous when mapping phenomena that change smoothly over a space, as the dot maps will visually match the phenomena. There are mainly two type of dot density maps namely one-to-one and one-to-many dot maps.

Dot density maps can be used in conjunction with other thematic maps to understand phenomena that occurs across the earth surface.

Check your knowledge:

  1. What is it useful to know population distribution:
    1. Because it will interrupt human activity like a farming
    2. For planning purpose, resources use against people
    3. It does not matter as long as we know the population density
  2. What is population distribution and how is it represented in a GIS:
    1. A type of gis dataset that shows how people behave
    2. The spread of people across the terrain
    3. Spread of points in a vector layer
  3. Is population distribution a type of dataset:
    1. True
    2. False

Further reading:

Click here to download the sample data for the lesson.