11/14/13

This weekend's homework is to work on the Primary Productivity lab write-up due later next week. See below for details of what you can/should work on. The more you work on/complete now the easier completing the final product will be.

Taken from today's handout...

4. Calculate the respiration rate. (Initial DO – Dark Bottle DO)

5. Calculate the gross productivity (Light bottle DO – Dark Bottle DO) and then the net productivity (Gross productivity – Respiration OR Light bottle DO – Initial DO) for each of the 5 bottles you were manipulating (100% light, 65%, 25%, 10%, 2%). Record the results of these calculations. NOTE: Each of the bottles you manipulated is considered a “Light bottle.” For example, if you were trying to determine the gross productivity of the 5% light bottle, then you would do the following:

5% bottle DO – Dark Bottle DO

6. The calculations will be based on the time period that we allowed our bottles to sit under the light. Share your data with Mr. Whelton and record the class average values.

7. Convert your calculations for mg O2/L to mL O2/L by using the following conversion formula:

mg O2/L x 0.698 = ml O2/L

8. Convert your calculations for ml O2/L to the amount of carbon assimilated by producers. You will do this using the following formula:

ml O2/L x 0.536 = mg C assimilated/L

Analysis

9. Thoroughly analyze your data. This means that you:

a. Graph both the net and gross productivities (as measured in both mL O2/L and mg C assimilated/L) as a function of light intensity.

b. Make inferences based on the data. Support these inferences by referring explicitly to your data.

c. Evaluate your hypothesis. Was it supported by your data? Support your conclusions by referring explicitly to your data.

d. Try to explain what happened in order to produce your data. For example, if you noticed an increase in dissolved oxygen, then why do you think that happened? What was happening inside of the bottle? The goal is to connect the experiment and your observations to the concepts from class.

Graphing Criteria Checklist

Labels	An informative title – ex. “The effect of ____ on ____” Labeled x- and y- axes Axes have units
Plotting	Ind & Dep variables graphed on appropriate axes Axes use appropriate scales Points/bars plotted correctly Data points are not connected
Formatting	Made using ruler Graph is made large and clear