Online exam environmental studies


Take-home final exam, ENVT 220 F3 2017

Historically, transpiration from the Amazon rain forests produced large amounts of water vapor; trade winds blew that moisture towards the Andes mountains, which deflected the moisture back towards the area of southern Brazil, where sugar cane is grown. The moisture formed precipitation there regularly, making the area agriculturally productive. For this reason, the windblown water vapor from the rain forests down to southern Brazil has been called “Flying Rivers”. But southern Brazil and cities nearby have been having a drought for several years. Scientists believe that this is due to deforestation of the Amazon rain forests.

1. Explain why deforestation would cause such a drought in this case. (3 points)

2. Suggest three strategies to respond to this problem for the people living in the drought-affected areas, and for the industrial agriculture (sugar cane) happening in those areas. (6 points)

3. Phosphate (PO​4​ ​

3-​) is necessary for life. What group of molecules in living things requires phosphate? (1 point) 4. Extra phosphate in wastewater is harmful for life in bodies of water, such as lakes and rivers. Where does extra phosphate come from in the wastewater, and why is the extra harmful to lakes and rivers? Why? (5 points) 5. The form of phosphate that is used in tap water (PO​4​

3-​) is a negatively-charged molecule also called “orthophosphate”. Orthophosphate is added to some cities’ tap water, as part of the water treatment process. Why? Please give exact details about all of the chemicals that are involved. (5 points) Hint: look for the word “Lead” on the Moodle.

The diagram above shows the Burbank water reclamation plant on Lake Street which we visited. 6. Figure out the water’s path through each labeled site in …