4. Pertinent Biological Processes Carbon Cycle Basics Important for living things Moves in a cycle from the of the atmosphere, plants, and animals Carbon is found in living things, the atmosphere, soil, water, and rocks © 2010 National Earth Science Teachers Association

5. Pertinent Biological Processes Nitrogen Cycle Basics Important for living things Found naturally in soil More nitrogen found in areas that have animal excrement and/or decaying living things Nitrogen-rich chemical and natural fertilizers used to enhance plant growth © 2010 National Earth Science Teachers Association

6. Role of Bison in the Prairie Historical Perspective Interaction of bison with the prairie History of destruction of bison and prairie Present Perspective Relatively few native or restored prairie Even fewer native or restored prairie with bison Relatively few studies on bison and the prairie Additional research is needed in order to better understand the interaction of bison with the North American tallgrass prairie

7. Questions and Hypotheses Purpose of Research Analyze the impact of grazing on soil nutrient levels in the prairies of Afton, MN Analyze the impact of grazing on prairie biodiversity Anticipated Outcomes Hypothesis 1: Nitrogen content < grazed prairie Plants being consumed will need to absorb more nutrients from the soil for aboveground growth Hypothesis 2: Nitrogen content > grazed prairie Grazing would stimulate nitrogen cycling through process of consumption, digestion, and excretion

9. Mammalian Herbivores: Ecosystem-Level Effects in Two Grassland National Parks Researcher: James K. Detling Where: Kansas and Wyoming Study: Effects of mammalian herbivore grazing on plant species composition, bio-mass, productivity, and nitrogen cycling Results: Biodiversity > in prairie grazed by prairie dogs Prairie dogs > impact on plant community Bison + prairie dogs > than each species alone N-concentration > in grazed prairie N-concentration and grass > where bison urinate Changes in biodiversity take years Variation in years of managed sites can be more influential than the impact of grazing (Detling 1998)

10. Mammalian Herbivores: Ecosystem-Level Effects in Two Grassland National Parks More forbs and dwarf shrubs present in the grazed prairie, however significant differences did not exist (P > 0.05) “There were remarkably few differences in plant cover…This result was unexpected in view of numerous reports of changes in plant species diversity, equitability, species richness, and species composition after exclusion of grazers from an area” (Detling 6). Possible factor: The amount of time in which the grazed prairie was grazed. The grazing enclosure was established in 1938, but most of this area had not been grazed since this time. Previous studies confirm that time impacts biodiversity. (Detling 1998)

11. Impact of Grazing on Soil Nutrients in a Pampean Grassland Researchers: Raul S. Lavado, Jorge O. Sierra, and Patricia N. Hashimoto Where: Pampean Grassland, Argentina Study: Effect of different grazing histories on the status and spatial variability of soil organic matter and major nutrients (nitrogen and phosphorus) Results: Nitrogen and phosphorus > excreta returns Grazing affects the pattern of spatial variability of C, N, and P and spatial distribution dependant on differential effects of animal excreta Carbon content of soil > soil surface litter (Lavado, Sierra, Hashimoto 1996)

12. Impact of Grazing on Soil Nutrients in a Pampean Grassland (Lavado, Sierra, Hashimoto 1996) No significant differences (p < 0.05) for organic carbon (OC) and total nitrogen (TN) between grazing conditions. Mineral nitrogen content higher in ungrazed areas on both dates >> Study recognizes that, “…Literature dealing with the effects of grazing on soil organic matter and nutrient status is sometimes contradictory…It is a reflection of different environments, soils and grazing management” (Lavado, Sierra, Hashimoto 2). Possible factor: Nitrogen content in ungrazed > grazed due to higher biological activity in grazed

13. The Keystone Role of Bison in North American Tallgrass Prairie (Knapp et al. 1996) Researchers: Alan K. Knapp et al. Where: Kansas Study: First synthesis of the research at Konza Prairie studying bison-tallgrass interactions since 1990 Results: Short-term different from long-term effects Biodiversity > in prairie grazed by bison Bison consume higher proportions of the dominant grasses while avoiding forbs Forbs > in prairie grazed by bison N-concentration > in grazed prairie Bison prefer grazing on urine-treated plots Leaf nitrogen content > in urine-treated plots Other effects of bison on prairie: wallowing and death also affect biodiversity and soil nutrients

14. The Keystone Role of Bison in North American Tallgrass Prairie (Knapp et al. 1996) Study states, “…Their [bison] effects on nitrogen cycling are critical because nitrogen availability often limits plant productivity in these grasslands (Seastedt et al. 1991, Blair 1997, Turner et al. 1997) and influences plant species composition (Gibson et al. 1993, Wedin and Tilman 1993)” (Knapp et al. 44).

16. Belwin Conservancy 1,300 acre preserve of oak savanna and woodlands, tallgrass prairie, wetlands and fens Dedicated to land conservation, scientifically–based ecological restoration Bison introduced in 2008

17. Data Collection Process Soil Nutrient Content Seven soil samples from grazed and ungrazed prairie taken with an auger approximately 18 cm below ground Samples taken with random number table Soil samples refrigerated for one week Moisture content, % organic matter, and C:N ratio assessed Data compiled and analyzed Plant Biodiversity Seven plots were assessed in the near vicinity of previous soil data collection sites Sample plots determined by throwing a frame over a patch of prairie Within this framed prairie patch, land cover of bare ground, litter, specific species of grasses, and specific species of forbs were estimated

18. Data Collection at Belwin Conservancy

20. Analytical Tools Carbon to Nitrogen Ratio Percentage of Organic Matter in Soil Percent Cover of Forbs and Grasses

21. Percentage of Carbon in Soil 1.60701.6623 Can conclude that there is no significant difference due to overlapping standard error bars

22. Percentage of Nitrogen in Soil 0.13790.1410 Can conclude that there is no significant difference due to overlapping standard error bars

23. Ratio of Carbon to Nitrogen in Soil t-test, p = 0.9 13.571013.6074 Can conclude that there is no significant difference (P > 0.05) because t-test indicates that P = 0.9

24. Percentage of Organic Matter in Soil 20.1666 18.5627 Can conclude that there is no significant difference (P > 0.05) because t-test indicates that P = 0.4

25. Percent Cover of Forbs and Grasses Forbs Goldenrod Marigold Desmodium Aster Sunflower White Sweet Clover Fescue Mint Golden Alexander Yellow Cone Ox-Eye Dandelion Grasses Brome Indian Grass Big Blue Stem Bare Ground Litter There is perhaps a trend that grazed prairie has a higher percentage of forbs than ungrazed, but there is no significant difference Grazed prairie has a lower percentage of grasses than ungrazed, and there is significant difference P = 0.028 (P > 0.05)

26. Prairie Biodiversity

29. Conclusions to Study

30. Factors Impacting Results Location of Study: Belwin Conservancy’s role in land management Number of years prairie has been grazed Number of bison grazing Amount of time annually that bison spend grazing Study Design: Sample size Amount of time in which samples are gathered Additional research is needed in order to better understand the interaction of bison with the North American tallgrass prairie

32. Works Cited Belwin Conservancy. "Bison." Belwin Conservancy. Belwin Conservancy, 2007. Web. 7 Dec 2010.. Belwin Conservancy. "Home." Belwin Conservancy. Belwin Conservancy, 2007. Web. 7 Dec 2010.. The Center for Innovation in Engineering and Science Education. "Nitrogen Cycle." Oceans Connecting a Nation. Stevens Institute of Technology, 2007. Web. 19 Oct 2010.. Detling, James K. (1998). Mammalian herbivores: ecosystem-level effects in two grassland national parks. Wildlife Society Bulletin, 26(3)1-12, Retrieved from http://www.jstor.org/stable/3783756 Dorn, Tom. "Nitrogen Sources." University of Nebraska Cooperative Extension in Lancaster County. University of Nebraska Cooperative Extension, 2001. Web. 19 Oct 2010.. Gardiner, Lisa. "The Nitrogen Cycle." Windows to the Universe. National Earth Science Teachers Association (NESTA), 07 May 2007. Web. 06 Dec 2010.. Johnson, Roberta. "The Carbon Cycle." Windows to the Universe. National Earth Science Teachers Association (NESTA), 07 Nov 2010. Web. 06 Dec 2010.. Knapp, Alan K., Blair, John M., Collins, Scott L., Hartnett, David C., Johnson, Loretta C., & Towne, E Gene. (1999). The keystone role of bison in north american tallgrass prairie. BioScience, 49(1), 1-13, Retrieved from http://www.jstor.org/stable/1313492 Lavado, Raul S., Sierra, Jorge O., & Hashimoto, Patricia N. (1996). Impact of grazing on soil nutrients in a pampean grassland. Journal of Range Management,49 (5) 1-7, Retrieved from http://www.jstor.org/stable/4002929 Tucker, M. Ray. "Essential Plant Nutrients: their presence in North Carolina soils and role in plant nutrition."North Carolina Department of Agriculture & Consumer Services. NCDA & CS Agronomic Division, Oct 1999. Web. 23 Nov 2010.