Take-home part of the Limnology Final Exam
Lake Wooten is a 7-acre lake located in suburban Kennesaw created by an earthen dam constructed more than 30 years ago.
Parameter / Data collected on 27 November 2017 / Historical data collected on 5 December 2016 / Historical data collected on 4 December 2013 / Historical data collected on29 November 2011 / Historical data collected on
3 December 2009 / Historical data collected on
27 November 2007 / Historical data collected by a previous KSU class in February- March 2004
Aquatic plants: / Potamogeton pusillus
(Small Pond Weed)
Myriophyllum aquaticum (parrotfeather watermilfoil) / No macrophytes observed / Zannechellia palustris (Horned Pond Weed) abundant in mid-lake
Myriophyllum aquaticum (parrotfeather watermilfoil) along margin of lake / Zannechellia palustris (Horned Pond Weed) / Hygrophila polysperma
(East Indian Hygrophila) / Zannechellia palustris (Horned Pond Weed)
Myriophyllum aquaticum (parrotfeather watermilfoil) / Not reported
Sites in order of 1 / 2 / 3 from left to right.
Site 1 was large embayment where largest creek entered
Site 2 was dock
Site 3 was smaller embayment near parking area and small incoming stream / Mid-lake /Dock
Temperature (°C): / 12.08 /11.11 / 10.49 / 10.75 / 10.4 / 12.2°C / 12.0°C / 10°C / 12.8°C / --
Specific Conductivity (µS/cm): / 43.6 / 43.2 / 44.2 / 54.2 / 45.9 / 52.0 µS/cm / 47.3 µS / 38.5 µS / 43 µS / --
Dissolved Oxygen (mg/l): / 8.90 / 8.90 / 4.57 / 6.25 / 9.0 / 7.22 mg/l / 5.09 mg/l / 7.79 mg/l / 7.49 mg/l (71% sat.) / 10 mg/l
pH: / 7.7 / 8.0 / 7.6 / 8.81 / 6.36 / 6.44 / 6.2 / 6.78 / 7.04 / 6.0 – 8.5
Chlorophyll (ppb): / 12.5, 14.1, 0.6 / 5.2 / 1.9 ppb / n/a / 3.1 ppb / 3.2 ppb / 4.0 ppb / --
Turbidity (NTU): / 6.80, 4.50 / 3.91, 3.44 / 2.42, 1.86 / 8.43 / 9.1, 9.0 / 4.9, 4.7 NTU / 7.81, 7.97 NYU / 14.8, 14.7 NTU / 3.79, 3.49, 3.57, 3.52 NTU / 27-210 NTU
TSS (mg/l) / 9, 9 / 12, 10 / 26*, 30*
*bottom likely disturbed as sample was taken
Secchi depth (m) / n/a / 1.8 / 0.9 m / 1.1 m / 0.95 m / 0.71, 0.55. 0.58 m / 2.0 m / 0.2-0.7 m
(1.7 m in summer 2002)
Sediment depth (cm) / 0.597, 0.12.7, 0.006 / 0.10 (nearshore) / 0.13 m (dock) / 0.16 cm (dock) / 0.21 m (dock) / 0.24 m (mid lake) / n/a
Total Phosphorus / n/a / n/a / 79, 76 / 70, 67 ppb / 143, 203 ppb (µg/l) / n/a / n/a / n/a
Dissolved Phosphorus / n/a / n/a / 16, 21 / 35, 46 ppb / 31, 33 ppb (µg/l) / n/a / 103, 106 ppb (µg/l) / n/a
Ammonia / n/a / n/a / 94, 105 / 106, 96 ppb / 262, 269 ppb (µg/l) / n/a / 890, 930, 830 µg/l / 150 - 370 µg/l
Nitrate / n/a / n/a / 217 ppb / n/a / 192, 176 ppb (µg/l) / n/a / n/a / 120 – 290 µg/l
Fecal Coliform Bacteria / n/a / n/a / n/a / n/a / n/a / 19 colonies / 100 ml / 30 colonies / 100 ml
Fluorescence / 118, 106 / 88, 87 / 19, 21 / 68.0 / n/a / 59.2, 58.7 / 62.5 / n/a / n/a
Alkalinity / n/a / n/a / n/a / n/a / 70 mg/l as CaCO3 / n/a / n/a
Photic depth / n/a / n/a / n/a / 0.69 at surface
0.35 at 0.35 m
0.21 at 0.60 m
0.12 at 0.75 m / 0.63 at surface
0.37 at 0.25 m
0.19 at 0.50 m
0.08 at 0.75 m / n/a / n/a
State standards for swimming are <200 colonies / 100 ml.
State standard for surface D.O. is >4.0 mg/l.
“n/a” = not available
Assignment:
1. Identify the most likely uses (goals) for the lake for property owners living next to the lake.
2. Based on your answer to Question 1, your observations of the watershed, the data you collected, identify what might be the greatest problem or potential threat to these uses/goals. Explain. Are you confident of this assessment? Why/Why not?
3. Recommend two management strategies to address the problem and achieve the desired goals (or to maintain it against its greatest threat). For each, explain in a paragraph how this strategy will work and why it was chosen. At least one of the strategies should be a standard technique used in lake management (with the other you may be creative, but be sure again to explain how it will bring about the desired change). Cite at least one source (other than in-class lectures; web sources are acceptable). Be specific (i.e. don’t just say “dump some pesticides in it”, or “clean up the watershed).
4. Write a paragraph explaining possible negative outcomes that your strategies could result in? What other data/information might you need in order to be more confident that your strategy will work as planned? Explain.
5. Turn this assignment in to Turnitin.com
DO THIS EXAM COMPLETELY ON YOUR OWN! You may use historical data as well as this year’s data in your arguments.