7.3 Down to the Last Drop

Engage: can human actions alter water resources?

Step 1: Go to the ArcGIS Online map, Down to the Last Drop, and explore the map.

Step 2: Examine the recent view of the Aral Sea in Central Asia.

Step 3: With the Details pane visible, click the button, Show Contents of Map.

Step 4: Click the checkbox to the left of the layer name, Aral Sea, 2000 (image) & 1960 (black outline). The image is from 2000, and the outline shows the 1060 extent of the sea before humans began to alter water flow to the Aral Sea.

  • One physical change that can be seen in the Aral Sea since humans altered the water flow is the smaller, shallower, upper portion remains more intact after a dam was added between the north and south sections.

Explore: where are other lakes and rivers that are drying up due to human actions?

Step 5: Click the Bookmarks button. Select one of the other location bookmarks for a closer examination.

Step 6: Click the map marker to view detailed information about human alterations to this water resource.

  • What human events have caused changes in water resources?
  • What natural events have caused changes in water resources?

Explain: why is the water to the Aral Sea decreasing?

Step 7: Click the Bookmark, Aral Sea Region.

  • Do both rivers reach the Aral Sea? (Zoom in and out)

Step 8: Turn on the layer, Aral Sea Watershed Dams.

Step 9: Turn on the layer, Irrigated Lands in Aral Watershed.

  • Do dams or canals have the most significant impact?
  • What factors could influence the placement of the dams and canals?

Elaborate: how would the Aral Sea drying up affect the surrounding areas?

Step 10: Turn on the layer, Aral Sea Dust Impact. Zoom out to see the impact area.

Step 11: Increased dust and salt storms sometimes send dust 500 km from the Aral Sea.

  • Dry lake beds of the salty sea that have no vegetation are causing the dust and salt storms. (T/F)
  • What environmental, economic, and human health effects might this have on the surrounding areas? (Look closely at the areas within the buffer.)

Evaluate: how has human alteration affected the Colorado River?

Step 12: Press the button, Bookmarks. Select the Colorado River Basin Dams and Canals.

Step 13: Zoom in and out to identify human alterations and causes.

  • What are some similarities and differences between the effects of human alterations on the Colorado River and the Aral Sea?‚Äč

License

Icon for the Creative Commons Attribution 4.0 International License

Human Geography Lab Manual by R. Adam Dastrup, MA, GISP is licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted.

Share This Book