Math 1020, Mathematics for the Liberal Arts, Fall 2015

Activity #04, Potential Ecological Use

Wednesday, September 09th

Learning Outcomes:

• More with Σ notation

• Careful organization of summary data

• Careful interpretation of organized summary data

NAME(s)______

Potential ecological use of a stream reach is broken down into the same five classifications as existing ecological use, but is calculated very differently. Potential use is based on the environment of the waterway – both in the stream, lake, or river itself, and what’s around it - while existing use is based on what marine life actually lives there.

Since there are a great many factors which impact the livability of a waterway for various organisms, as one might expect, the data processing for classifying a potential ecological use is a bit involved! The basic rubric (scheme for arriving at the classification) is shown in Table EUC 4, handed out with this activity. Minimum flow, minimum dissolved oxygen, temperature, and pH level (acidity) are all crucial factors in determining what kinds of organisms can survive in a waterway. Take a moment to familiarize yourself with this chart.

All of the numbers needed for the classification must be collected by actually visiting the creek and making observations and taking measurements. We are going to take advantage of fieldwork done in 1997 and 2003 by employees or contractors of Barr Engineering, an environmental engineering company in Edina which does contract work for the Nine Mile Creek Watershed District. Specifically, we’ll use their field observations and measurements to classify the potential ecological use of Reaches 3A, 7A and 7C (three of the reaches whose existing ecological use we calculated on Wednesday in Activity 3). The most interesting, and complicated (from a data-collection standpoint) part of the classification deals with finding the “habitat rating.” This is a positive number which seeks to summarize a wide variety of ecological features of the waterway. The worksheet for making these calculations is included in the handouts. You’ll notice the “Σ” notation is used here as well! That means you’ll be adding numbers together to arrive at this rating.

To find the habitat rating, the field workers either measure things (like creek flow rate, water depth, channel capacity) or make qualitative judgments about conditions(aesthetics, erosion, nonpoint pollution sources). Each observation is given a numerical rating.

Question 1. From the habitat rating sheets, do higher numerical values mean better conditions or worseconditions? (No explanation needed.)

Each of the three reaches surveyed has the rating assigned it by the field team, in each category, circled. To calculate the habitat rating, add each column total (Excellent, Good, Fair, Poor) and record that sum in the space provided; then add those four subtotals in the space provided at the very bottom of the rating sheet. For ease of grading, I’ll also have you report the totals on this worksheet.

Reach 3A:

Question 2. What is the subtotal from the “Excellent” column?

Question 3. What is the subtotal from the “Good” column?

Question 4. What is the subtotal from the “Fair” column?

Question 5. What is the subtotal from the “Poor” column?

Question 6. What is the total habitat rating score (i.e. numerical) for Reach 3A?

Question 7. Using the scale at the bottom of the rating sheet, is Reach 3A’s habitat classified as “Excellent,” “Good,” Fair,” or “Poor?”

Reach 7A:

Question 8. What is the subtotal from the “Excellent” column?

Question 9. What is the subtotal from the “Good” column?

Question 10. What is the subtotal from the “Fair” column?

Question 11. What is the subtotal from the “Poor” column?

Question 12. What is the total habitat rating score (i.e. numerical) for Reach 7A?

Question 13. Using the scale at the bottom of the rating sheet, is Reach 7A’s habitat classified as “Excellent,” “Good,” Fair,” or “Poor?”

Reach 7C:

Question 14. What is the subtotal from the “Excellent” column?

Question 15. What is the subtotal from the “Good” column?

Question 16. What is the subtotal from the “Fair” column?

Question 17. What is the subtotal from the “Poor” column?

Question 18. What is the total habitat rating score (i.e. numerical) for Reach 7C?

Question 19. Using the scale at the bottom of the rating sheet, is Reach 7C’s habitat classified as “Excellent,” “Good,” Fair,” or “Poor?”

Now refer to the data in Table EUC 5 for each reach to complete the potential use classifications.(Pretend that the potential ecological use as determined by Barr Engineering isn’t already listed…) ;-)

Reach 3A:

Question 20 (repeat of question 7): What was the habitat rating for Reach 3A?

Question 21. What is the minimum flow (in cubic feet per second, cfs)?

Question 22. What is the minimum dissolved oxygen, in milligrams per liter (mg/L)?

Question 23. What is the maximum temperature?

Question 24. What is the pH range?

Question 25. Combine the observations in the last 5 questions to determine the potential ecological use of Reach 3A by locating each observation in the chart from Table EUC 4. Which of the factors in Table EUC-4 determined the potential ecological use you report?

Reach 7A:

Question 26 (repeat of question 13): What was the habitat rating for Reach 7A?

Question 27. What is the minimum flow (in cubic feet per second, cfs)?

Question 28. What is the minimum dissolved oxygen, in milligrams per liter (mg/L)?

Question 29. What is the maximum temperature?

Question 30. What is the pH range?

Question 31. Combine the observations in the last 5 questions to determine the potential ecological use of Reach 7A by locating each observation in the chart from Table EUC 4. Which of the factors in Table EUC-4 determined the potential ecological use you report?

Reach 7C:

Question 32 (repeat of question 19): What was the habitat rating for Reach 7C?

Question 33. What is the minimum flow (in cubic feet per second, cfs)?

Question 34. What is the minimum dissolved oxygen, in milligrams per liter (mg/L)?

Question 35. What is the maximum temperature?

Question 36. What is the pH range?

Question 37. Combine the observations in the last 5 questions to determine the potential ecological use of Reach 7C by locating each observation in the chart from Table EUC 4. Which of the factors in Table EUC-4 determined the potential ecological use you report?