1. Effect of atmospheric deposition of nitrogen on the fixation and assimilation of nitrogen by wild lupine (Lupinus perennis) in the sand dunes of Lake Michigan Lauren Avans Purdue University Calumet, Hammond, IN Faculty Advisor: Young D. Choi

2. Introduction Located at the Lake Michigan Dunes Karner Blue Butterfly is an endangered species Sole food source of Karner Blue Butterfly Increase in Nitrogen Deposition recently I hypothesize that the addition of nitrogen in the soil will increase the biomass production of wild lupine.

3. Methods Germinated in dishes and transplanted Randomly assigned NH 4 NO 3 Treatment groups: Water, 7.5g m -2, 15g m -2 Harvested 5 months later Total dry weight biomass and biomass allocation analysis through: – Kruskal-Wallis test – Linear regression analysis

4. Median total biomass of wild lupine seedlings. Results were significant at p<0.05. n=12. * represents outliers. Total dry weight biomass of wild lupine (Lupinus perennis) ControlLowHigh Mean ± SE 224 ± 4 mg198 ± 4 mg137 ± 3 mg Median 201 mg168 mg130 mg

5. Median belowground biomass allocation of wild lupine seedlings. Results were significant at p<0.06. n=12. * represents outliers. Belowground biomass allocation by wild lupine ControlLowHigh Mean ± SE 62 ± 5%60 ± 2%52 ± 4% Median 66%63%53%

6. Linear Regression Line showing a correlation between the amount of biomass allocated belowground (vertical axis) and the amount of total biomass (horizontal axis).

7. Summary Contradictory Population Decline Total biomass decrease as nitrogen increases Physiological Drought Reduction of below ground biomass allocation percent as nitrogen increase Below Ground Biomass Allocation Percent Increases as Total Biomass Increases Allomeric growth vs. Nitrogen increase

8. Acknowledgements This project was funded by Flora Richardson Foundation

9. Works Cited Driscoll, C., D. withal, J. Amber, E. Boyer, M. Castro, C. Cronan, C. Goodale, P. Groffman, C. Hopkinson, K. Lambert, G. Lawrence, and S. Ollinger. 2003. Nitrogen pollution in the northeastern United States: sources, effects and management options. Bioscience 53: 357-374. Forrester, J. A., D. J. Leopold, and S. D. Hafner. 2005. Maintaining Critical Habitat in a Heavily Managed Landscape: Effects of Power Line Corridor Management on Karner Blue Butterfly (Lycaeides melissa samuelis) Habitat. Restoration Ecology 13(3): 488-498. Grundel, R., N. B. Pavlovic, and C. L. Sulzman. 1998. The effect of canopy cover and seasonal change on host plant quality for the endangered Karner blue butterfly (Lycaeides melissa samuelis). Oecologia 114: 243- 250. Grundel, R., N. B. Pavlovic, and C.L. Sulzman. 1999. Nectar Plant Selection by the Karner Blue Butterfly (Lycaeides melissa samuelis) at the Indiana Dunes National Lakeshore. The American Midland Naturalist 114: 1-10.