AP Environmental Science s5

APES: The Aral Sea v. The Salton Sea – Lessons Learned Name______

Overview The Salton Sea , located in Imperial County of Southern California, is a saline lake that was formed in a large basin (called the Salton Trough) created by releasing bend of the San Andreas fault. In modern times, the Salton Trough became a lake in 1891, but dried up within a year. It began to form again in 1893. In 1905, the Colorado River was diverted into the Salton Trough to create the Salton Sea. The Salton Sea was originally a fresh water lake. The Aral Sea , located in Uzbekistan and Kazakstan (both countries were part of the former Soviet Union), is historically a saline lake. It is very much like the Salton Sea of Southern California, except much larger. The Aral Sea was also formed in a basin formed by a releasing bend of a strike slip fault. The Aral Sea and the Salton Sea are both prime examples of dynamic environments. The Aral Sea is considered a true environmental disaster, but most students do not think this could ever happen in the United States, much less in their own back yard. By making students aware that the Aral and Salton Seas share many similarities, we hope that students will become more environmentally conscious. It may be too late to "save" the Aral Sea, but there is still hope to prevent the ecological collapse of the Salton Sea.

Using internet resources as well as your book, please answer the following questions that help to compare the causes and effects of environmental degradation resulting in both areas.

The Aral Sea

Find the location and other information about the Aral Sea from the Internet. Just a few sites are included on my website.

1. What former Soviet republics border the Aral Sea?

2. What main rivers supply the Aral Sea?

3. Why was the water supply to the Sea diverted?

4. What resources did the Sea supply to the local inhabitants?

5. Name five negative effects of the sea's disappearance on the environment.

6. Instead of as a "sea" how would you describe the region today?

7. List six health effects on people related to the vanishing Aral Sea.

8. Do you think that the Aral can be mitigated, reclaimed or rehabilitated? Describe steps you think could be taken to improve the region. The Salton Sea Find the location and other information about the Salton Sea from the Internet. Just a few sites are included on my website.

1. Where is the Salton Sea located? Be specific.

2. What main sources of water supply the Salton Sea?

3. What is the major problem facing the Salton Sea today?

4. What is the salinity of the Salton Sea? Is this higher or lower than ocean salinity (35 ppt)?

5. Do you think that the Salton can be mitigated, reclaimed or rehabilitated? Describe steps you think could be taken to improve the region.

SUMMARY EXERCISE Please list the similarities between the Salton (SS) and the Aral (AS) Seas. You can use a giant Venn Diagram, construct a chart, make a foldable, … whatever works for you. Similarities between the Salton (SS) and the Aral (AS) Seas

Recent major environmental changes that were caused by humans.

Potential dangers from military toxins/wastes.

Loss of fisheries due to human-caused environmental changes.

Sea water that is polluted by sewage, pesticides, defoliants, selenium (SS), agent orange (AS), and DDE (SS).

Salinity at near-fatal (SS) or fatal (AS) level for sea-living organisms.

Salinity levels that are still on the rise.

Major source of airborne particles (dust) for their respective regions.

Cotton growing regions.

Closed systems, with no outlet except for evaporation.

The health of animals and people in the areas have been negatively affected.

Long history of natural cycles of drying up and re-establishing bodies of water.

Political issues are encountered when trying to deal with the environmental problems. Issues concerning the Salton Sea need to be addressed by the United States and Mexico. Aral Sea issues need to be addressed by five independent Asian countries; Uzbekistan, Kazakstan, Turkmenistan, Tajikistan and Kirghizstan. We have a good supply of space shuttle images of both regions.

Except for scale, the regions are very similar. The environmental problems of the Aral Sea are more advanced than those of the Salton Sea. If the environmental issues surrounding the Salton Sea are not dealt with, it will advance to a similar state to that of the present Aral Sea.