Ask: Where do crops grow best?

Step 1: Go to the ArcGIS Online map, Agricultural Patterns, and explore the map.

Step 2: Click the button, Bookmarks, and look at the various bookmarks for this map: Rocky Mountains, Egypt, Russia, Northern Africa, Eastern China.

The regions that have the most productive agricultural systems include Northern India because of its flat river valley plain; eastern China because of its temperature, climate, and regular rainfall; and southern Russia because of its excellent soil.

Acquire: what factors affect crop yield?

Step 3: With the Details button underlined, click the button, Content.

Step 4: To show a legend, click the layer name, Crop Yields.

Step 5: Click the button, Bookmarks. Select the North African bookmark.

• What are crop yields like in North Africa?

Step 6: Turn on the layer, Total Annual Precipitation.

• What observations can be made about precipitation?

Explore: does crop yield always depend on rainfall?

Step 7: Compare the precipitation and crop yield layers by turning them on and off.

• Crops can grow within the deserts despite the lack of precipitation because of nearby rivers and irrigation.

Step 8: Turn off the layer, Precipitation.

Step 9: Turn on the layer, World Hydro Reference Overlay.

Step 10: Click the button, Bookmarks. Select, Egypt. Note the dense crop yield near the mouth of the Nile and along it.

• The reason why a place with so little rain can be a productive agricultural region is that rainfall from the Ethiopian highlands flows north, creating the Nile River, a source of water and rich sediments for Egypt.

Analyze: what role does temperature play in crop YIELDS?

Step 11: Click the button, Bookmarks. Select, Russia.

• What pattern do you observe in northern Russia?

Step 12: Turn on the layer, Average Terrestrial Surface Temperature.

Step 13: Compare the crop yield and temperature layers by turning the layers on and off.

• Do the temperature crop yield layers show similar patterns?
• How do cold and freezing soil temperatures affect vegetation and crop yield?

Step 14: Turn on the World Climate layer and turn off the temperature layer.

Step 15: Click the darkest green areas of crop yields.

• Which climate zones correspond to areas with the highest crop yields?

Act: how does agriculture affect the population?

Step 16: Have only the Population Density and Crop Yield layers turned on.

Step 17: Compare the layers by turning them on and off.

• What is the relationship between agriculture and population density?