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 ArcGIS 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 relief.mxd ArcMap document you saved in Activity 2.
Step 2.Select the Add Data tool and add the following shapefiles: manuf.shp, minerals.shp, and mining.shp.
Step 3.Turn off all layers except for "country.shp" (uncheck the boxes next to each layer to turn them off).
Step 4. Double click on the country.shp layer to access the Layers Properties and click on the Symbology tab. Change the symbol to "hollow" to make the country.shp transparent.
Step 5.Arrange the themes in the following order from top to bottom:
Step 6. Now let’s create separate map layers for gold, oil, diamonds, coal, copper, and uranium. Make sure the minerals layer is active (check mark in the box). At the top of the screen click "Selection" —> "Select by Attributes". Make sure "Mining" is the layer selected, double-click "Contents" from the display list, and click the equals sign. Next click the "Get Unique Values" button and double click "Au" (Gold). See image below. Click Apply and close the Select by Attributes box.
Step 7.All the gold mines are now selected (they should appear as blue dots). Now you are going to create a shapefile which saves your query in the form of a map. Right-click on mining.shp, and select "Data" —> "Export Data" (keep all the defaults) and name it Gold.shp.
Step 8.Repeat steps 6 and 7 to create shapefiles for oil, diamonds, coal, copper (Cu), 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 Data 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. Turn off all layers except for mining.shp and country.shp.
Step 13. Now let’s see which mining operations are the largest. You may need to turn off the selected layers if you still have blue dots on your map. To do this click "Selection —> Clear Selected Features". Double click on the mining.shp layer to access the Layers Properties and click on the Symbology tab. Click on "Categories" and select "Unique Values". Under Value Field, select "Size" and click "Add All Values". Click apply and close the Layer Properties dialog box.
Step 14. Using the Identify tool , click on several of the "very large" mines. You may want to change the color to make them show up better. To do this, double click on the small dot next to "very large" under Mining. Change the color to red and change the size to 15.
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" layer active and use the identification tool to identify the countries.
Step 16. Deselect relief.shp and mining.shp to make them invisible. Add layer popden.shp and make it visible. Double-click on it to call up the layer properties, and under the Symbology tab, click "Quantities" and select "Graduated Color". Select "Density" as the "Value Field" and 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 layers: 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 (see step 14). 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 ArcGIS.
*** End of Africa Activity 3 for ArcGIS ***
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