1. How simplistically can I model O2 dynamics and still learn something?

2. night day Time Oxygen Concentration

3. O 2 sensor pelagic littoral mixed layer

4. O 2 site 1 (littoral) O 2 site 2 (littoral) O 2 site n-1 (pelagic) O 2 site n (pelagic) PP L PP P PP L PP P PP p RLRL RPRP gas ex. RLRL RPRP RPRP RPRP horizontal dispersion, Kh ??? Shore Center of the lake

5. Model Test and Hypothesis Examine how differences in Kh influence mid-lake estimates of whole-lake metabolism Hypothesis: At low Kh – mid-lake sensor = pelagic metabolism At high Kh – mid-lake sensor = whole-lake metabolism

6. Kh =.1692 m 2 /hr

7. Kh = 1 m 2 /hr

8. Kh = 10 m 2 /hr

9. Kh = 100 m 2 /hr

10. Kh = 1000 m 2 /hr

11. Mid-lake estimates of GPP

12. 80-m transect vs 1000-m transect

14. Conclusions Over a range of likely mixing regimes, mid- lake sensors will detect a mixture of pelagic and whole-lake signals At some levels of mixing there will actually be an underestimate of even the pelagic signal Therefore there is a need to better understand the horizontal mixing regimes in small lakes

15. Further Study Examine how lake size influences the results Examine different ratios of pelagic-littoral metabolism Examine gas exchange affects