Activity Option 6.1 - Phosphorus Mining and Impacts
- Describe how different stages of phosphate extraction and use (mining, beneficiation, production, consumption, and/or disposal) affect land use, pollute land, air, and/or water, and create wastes, and discuss how waste products are/can be managed.
- Describe the phosphate cycle and how the use of chemical phosphate fertilizer alters this cycle.
- Identify stakeholders, explain their viewpoints, and weigh their diverse views in determining if, how, and where to mine and use phosphate resources.
- Make informed predictions of future supply, demand, and impacts of phosphate, based on (a) population change, (b) technology change, and (c) people's choices, specifically addressing how personal choices impact resource sustainability.
Context for Use
This activity is a way for students to juxtapose what they have learned about mineral resources, economic drivers, mining, beneficiation, and reclamation and stress the societal issues associated with natural resource extraction. The activity is a jigsaw in which students become familiar with the opinions of one type of stakeholder, then come together with different experts (their peers who investigated slightly different topics) to conclude what should and can be done about future phosphate use.
Description and Teaching Materials
Overall Layout of Phosphorus Activity:In this jigsaw, the exercise is divided into two main segments. Here is the overall concept:
- Segment 1 (30 minutes; or 10 minutes, if students did the assignment as homework):
- Students are split into four small groups. Each group has a different, but related, assignment. Thus you have four groups learning slightly different content/skills.
- The four groups and their topics for this exercise are:
- Group 1: Mining: U.S. and Global Production and Consumption
- Group 2: Some Effects of Phosphate Mining, Processing, and Use on Land and Water
- Group 3: Fertilizer Use and the Phosphate Cycle
- Group 4: The Economics and Politics of Phosphorus
- Segment 2 ( about 40 minutes):
- Once Segment 1 is completed, students are divided into a second group. Each of these new groups has a single member from each of the original groups (or as close to that as possible). Thus each new group will have the collective knowledge from all of the first groups.
- All groups complete a single assignment, bringing together the information/skills they gained from the previous segment (in addition to content learned prior to this unit).
- Instructions are also provided for completing segment 2 as a whole-class discussion.
For large classes, a number of jigsaw groups could be set up (i.e., many Segment 1 groups completing Group 1 work, etc).
The pre-class reading provided below is intended to introduce students to important concepts within this unit and expose students to slightly more information than will be covered during class time. If instructors feel that they want to review all of the concepts addressed in these readings during class, they will need to add time or adjust/edit the activities.
Jigsaw - Segment 1 can be done as pre-class homework if the instructor chooses. Assign students into one of the four groups by giving each student one of the following Segment 1 assignments as homework.
Jigsaw - Segment 1 (30 minutes; 10 if students did Segment 1 as homework)
- Explain the overall goals of the assignment as well as the general structure/format of the jigsaw. Remind students that they will be the only representative from their Segment 1 group in their second (Segment 2) group, so they should strive to understand the material.
- *Move students into Segment 1 groups and let them work together. Ideally these groups would contain 4--6 people; large classes can create multiple groups (for example, have two Group 1s, two Group 2s, etc.).
- Ask students to (a) discuss their answers, (b) reconcile any differences in answers, (c) summarize the key points of their assignments, and (d) list the stakeholders (people, or even nonhumans, who care about phosphorus) that emerged from this activity. Answer keys (or partial answer keys) can be provided to students to ensure they got the correct answers.(*Skip 2 if students did this segment as homework.)
Segment 1 Group Topics and Assignments:
Segment 1 / Group 1. Mining: U.S. and Global Production and Consumption: Group 1 will read about the potential expansion of a phosphate mine in Florida. They will also compare U.S. consumption to global per capita consumption, and consider U.S. and global production and use to calculate how long our phosphate reserves will last.
Segment 1 / Group 2. Some Effects of Phosphorus Mining, Processing, and Use on Land and Water: Students in Group 2 will read about pollution from two different fertilizer plants in Florida. They will also consider bioaccumulation of cadmium derived from phosphate fertilizers.
Segment 1 / Group 3. Fertilizer Use and the Phosphorus Cycle: This group will apply the phosphorus cycle to three things: (1) The removal of harvested plants has an effect on soil phosphorus. There will be additional impacts on soil phosphorus if the proposed plans to remove stover from fields (to use in ethanol generation) come to pass. (2) Phosphorus is a required nutrient for plants and studies have shown the link between crop yield and phosphate fertilizer use. (3) Changes to the phosphorus cycle can lead to increased levels of phosphorus in surface water, which causes eutrophication.
Segment 1 / Group 4. The Economics and Politics of Phosphorus: This group investigates the role of imports in the U.S. supply of phosphorous and considers reasons why mineral companies consider politics (of Morocco and Western Sahara) in import decisions.
Jigsaw - Segment 2 (40 minutes)
- Split students into Segment 2 groups. Each group should have at least one person from each Section 1 group, ideally with no more than 6 per group.
- Hand out the Segment 2 group assignment to the students. This activity should force students to share what they learned from their individual groups above.
Segment 2: Final Group Activity Grading Rubric in Word (Microsoft Word 2007 (.docx) 136kB Oct6 14) and in PDF. (Acrobat (PDF) 63kB Oct6 14)
Alternate Version of Segment 2---Whole-Class Discussion (still a jigsaw, but with a larger completed puzzle):
- While students are still in their Segment 1 groups and after they have compared worksheet answers, ask students to answer three additional questions: (1) Who cares about phosphate? (2) What concerns exist around phosphate mining/processing/use? and (3) What can be done to alleviate some of the concerns?
- As a whole class, have students report out their answers to 1--3. Write these on the board, so that students can see what has already been said. The instructor should probe groups for more answers if they seem to be missing a/the point. Also, the instructor can clarify confusing points.
- When discussing the question, "What can be done to alleviate some of the concerns?" the instructor should pointedly ask students, "Should YOU care about phosphate?"
Optional Post-Class Homework
A writing assignment can be used to have students summarize (and thus think about) what they learned in class, as well as consider their personal ties to the phosphate story.
Optional Unit 6 Phosphorous Post-Class Homework in Word (Microsoft Word 2007 (.docx) 61kB Oct6 14) and in PDF. (Acrobat (PDF) 46kB Oct6 14)
Teaching Notes and Tips
- To accommodate six (instead of four) groups, Segment 1 / Group 2 can be split into two, and Segment 1 / Group 3 can be split into two. For large classes, multiple groups can tackle each aspect of Segment 1. Segment 2 groups (if done as groups) should ideally be kept to 4--6 students.
- For more information on jigsaws as teaching techniques, please see: https://serc.carleton.edu/sp/library/jigsaws/index.html.
Students will use answers from their first round of group work to answer questions with their final group. The final group questions can be collected and assessed.
Assessments and Learning Outcomes
The learning outcomes are addressed by the activity questions as listed below :
- Describe how different stages of phosphate extraction and use (mining, beneficiation, production, consumption, and/or disposal) affect land use; pollute land, air, and/or water; and create wastes, and discuss how waste products are/can be managed: Pre-class reading, Groups 1, 2 and 3; Segment 2 Activity; Homework.
- Describe the phosphate cycle, and how the use of chemical phosphate fertilizer alters this cycle: Pre-Class Reading; Group 3.
- Identify stakeholders, explain their viewpoints, and weigh their diverse views in determining if, how, and where to mine and use phosphate resources: Groups 1, 2, 3, and 4; Segment 2 Activity.
- Make informed predictions of future supply, demand, and impacts of using the mineral resource, based on (a) population change, (b) technology change, and (c) people's choices, specifically addressing how personal choices impact resource sustainability: Groups 1, 2, 3 and 4; Segment 2 Activity; Homework.
Segment 1 assignments can be collected and graded, or else student's Segment 1 answers can be spot checked as they work, or students can check their answers against provided answer keys.
A rubric for grading Segment 2 (in small groups) is given above (instructors should feel free to change the total point value of the assignment).
The whole-class discussion (an informal assessment) can be used to judge whether or not students accomplished their goals.
A grade sheet is included above for the optional homework assignment (instructors should feel free to change the total point value of the assignment).
Possible Exam Questions
Unit 6 Phosphorous Self-Assessment Questions in Word (Microsoft Word 39kB Oct6 14) and in PDF. (Acrobat (PDF) 61kB Oct6 14) These can also be found in the Unit 6 Phosphorous Student Materials Reading.
Unit 6 Phosphorous Self-Assessment Questions Key in Word (Microsoft Word 39kB Oct6 14) and in PDF. (Acrobat (PDF) 78kB Oct6 14)
References and Resources
- USGS Fact Sheet on Fertilizers.
- SERC's Page on the Gulf of Mexico Dead Zone.
- The final group activity was modeled after GeoEthics forums presented by Shaun Taylor, at http://serc.carleton.edu/geoethics/activities/83374.html.
- Donville, Christopher. August 2, 2010. "Mosaic to Close Florida Phosphate Mine after Ruling on Plan for Expansion." Bloomberg News.
- Scheyder, Ernest. July 11, 2011. "Judge's Ruling Extends Mosaic's Florida Mine Woes." Reuter's News.
- Spinner, Kate. February 21, 2012. "Mosaic Reaches Settlement Over Fort Meade Mine." Sarasota Herald Tribune.
- USGS Mineral Commodity Summary: Phosphate Rock. 2012.
- Performing an Internet search for Florida phosphate mine might result in new discussions about mine expansions in Florida.
- Questions 3 and 4 on Part 2 rely on census data, which probably will not be updated until 2020. Questions 6 and 7 mention current reserves. The most recent estimates of reserves can be found in the USGS Mineral Commodity Summary: Phosphate Rock (found at http://minerals.usgs.gov/minerals/pubs/commodity/phosphate_rock/).
- Mendes, Alessadandra Monteiro Salviano, Duda, Gustavo Pereira, Araujo do Nascimento, Clistenes Williams, Silva, Michelangelo Oliveira. 2006. "Bioavailability of Cadmium and Lead in a Soil Amended with Phosphorus Fertilizers." Scientia Agricola 63, no. 4: 328--32.
- Pittman, Craig, Hauserman, Julie, and Rondeaux, Candace. July 6, 2003. "Piney Point 2003 Spill a $140-Million Mess." St. Petersburg Times.
- Spinner, Kate. January 6, 2011. "Manatee's Environmental Scourge Recast as an Asset." Herald Tribune.
- Spinner, Kate, and White, Dale. June 1, 2011. "Water Leaking from Mound of Radioactive Waste near Port Manatee." Herald Tribune.
- Stockton, Halle. June 29, 2011. "Piney Point Spill Twice as Large as Estimated."Sarasota Herald Tribune.
- Zink, Janet. September 10, 2004. "Fertilizer Plant Gets Set for Ivan." St. Petersburg Times.
- Zink, Janet. September 7, 2004. "Acidic Spill Tops 41-Million Gallons." St. Petersburg Times.
- Zink, Janet, James, Joni, and Varian, Bill. September 6, 2004 "Acidic, Radioactive Water Spills into Bay." St. Petersburg Times.
- Mullins, Gregory. 2009. "Phosphorus, Agriculture and the Environment." Virginia Cooperative Extension, Virginia Tech.
- Rehm, George W., Schmitt, Michael A., Lamb, John, and Eliason, Roger. 2012. "Fertilizing Soybeans in Minnesota."
- Data for Lake and River Phosphorus Levels from EPA STORET http://www.epa.gov/storet/.
- Hawken, Paul, Lovins, Amory, and Lovins, L. Hunter.(2008. Natural Capitalism: Creating the Next Industrial Revolution. Back Bay Books.