Goal: In this lesson you will build upon maps created in Activity 2. These maps will help answer questions about the interrelationships among resources, the human environment, and the physical environment of Africa.
GIS Skills Involved: Map symbolization and the creation of new map layers using attribute data.
Materials: To complete this lesson you will need ArcView software and the Africa Lesson data (Download the Data for Activities 1-3).
Step 1. Let’s make a map showing energy resources in Africa. Open the ArcView project you saved in Activity 2 by using File—> Open Project. Open the "Relief" view by double-clicking on it.
Step 2.Using the Add Theme tool , add the following shapefiles: manuf.shp, minerals.shp, and mining.shp.
Step 3. Turn off all themes except for "country.shp" (uncheck the boxes next to each theme to turn them off).
Step 4. Make country.shp active by single-clicking on the name of the theme. Access the legend editor by double-clicking on the theme name. When the legend editor appears, double click under "Symbol" and then choose the paintbrush symbol . Click in the upper left box of the color palette to make it transparent. Click "Apply" and close the legend editor.
Step 5.Arrange the themes in the following order from top to bottom:
Step 6. Let's open the Theme Table for the minerals.shp layer. A Theme Table contains information about the geographic features contained in the file. Click on the "Theme Table" tool to see all the attributes of the minerals.shp layer. You will notice a field called "Contents". These are all different types of minerals contained in this shapefile. Let's create separate map layers for the following minerals: gold, oil, diamonds, coal, copper, and uranium. Make sure the minerals theme is active (check mark in the box). Click on the Query Builder tool . Under the "Fields" category, double-click on "Contents", then click the equals sign, and end with a double-click on "Au" (Gold). Click on New Set and all the gold records should now be highlighted on your map.
Step 7. Now you are going to create a shapefile which saves your query in the form of a map. Under the "Theme" menu, click on "Convert to Shapefile" and name it gold.shp and save. Add it as a Theme to the View and click on it to make it visible. You should now see Gold.shp in your view window.
Step 8. Repeat steps 6 and 7 to create oil, diamonds, coal, copper, and uranium.
Step 9.Turn all layers off except for oil.shp and country.shp.
Step 10. Now let's add pipelines to the map. Using the Add Theme tool , add pipeline.shp and put a check mark next to it to make it visible. Your map should now show the country outlines, pipelines, and oil deposits.
Step 11. Answer the following questions using this map setup:
A) Notice the pipelines in north and West Africa and compare them to the pipelines in east Africa. How would you determine which pipelines are being used to import oil and which pipelines are being used to export oil?
B) Name three countries that are using pipelines to export oil (to see the country name click on the Identify tool and then click on the country):
C) Name three countries that are using pipelines to import oil:
Step 12. Deselect pipeline.shp and oil.shp to make them invisible. You should now have a map of only the outlines of African countries.
Step 13.Double-click on the "mining.shp" theme. Under Legend Type, select "Unique Value." Under the Values Field, go to Size and double click on symbol for very large. Using the paintbrush , make the symbol red and click "Apply." The red dots show the largest mining properties.
Step 14. Using the "Identify" tool , click on several of the red dots to determine the type of material mined (you may need to use your Zoom tools ).
Step 15. Complete the following steps to answer the questions:
D) Using the Identify tool , list 3 countries and the type of material mined there. You will need to make the "country.shp" theme active and use the identification tool to identify the countries.
Step 16. Deselect relief.shp and mining.shp to make them invisible. Add theme popden.shp and make it visible. Double-click on it to call up the legend editor, and change "Legend Type" to "Graduated Color". Select "Density" as the Classification Field, click "Apply" and close the dialog box. Make manuf.shp visible and move it to the top of the view window so it is above popden.shp.
E) Is there a correlation between manufacturing and population density?
Step 17.Uncheck the manufacturing and population density. Turn on the following themes: coal, uranium, copper, gold, oil, diamonds, and country. You will find it easier to distinguish between the different minerals if you make each one a different color and symbol. Starting with coal, do the following steps to change symbols:
Click "Apply." Do this for each of the 6 minerals.
F) Describe three things you notice about the patterns on the map.
Save your project and exit ArcView.
*** End of Africa Activity 3 for ArcView ***
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