1. Chronic eutrophication changes the plant community, but not resistance and resilience to drought Meghan Avolio & Sally Koerner Konza Meeting June 2016

2. Phosphorus Plots Experiment (P-Plots) Initiated in 2003 0 or 10 g m -2 N 0, 2.5, 5, or 10 g m -2 P Fully factorial design

3. The N and P additions caused the C 4 grasses to loose their dominance Avolio et al. 2014, Journal of Ecology Perennial C 4 Grass Annual Grass Perennial C 3 Grass Perennial Non-N-Fixing Forb Annual Forb Perennial N-Fixing Forb

4. The different communities also had greater variability among replicates Koerner et al. In Press at Journal of Ecology N0 P0 N0 P2.5 N0 P5 N0 P10 N10 P0 N10 P2.5 N10 P5 N10 P10 Treatment

5. The different communities also had greater variability among replicates Koerner et al. In Press at Journal of Ecology N0 P0 N0 P2.5 N0 P5 N0 P10 N10 P0 N10 P2.5 N10 P5 N10 P10 Treatment

6. The different communities also had greater variability among replicates Koerner et al. In Press at Journal of Ecology N0 P0 N0 P2.5 N0 P5 N0 P10 N10 P0 N10 P2.5 N10 P5 N10 P10 Treatment

7. Question Do the different plant communities, derived after 8 years of nutrient additions vary in their ability to resist and recover from (resilience) drought? Hypothesis: The weedier plant communities will not be able to resist drought and will recover less quickly compared with native tallgrass prairie communities T = 1 High Low Resistance Resilience T = 1 High Low T = 2

8. P 3 – Phosphorus Precipitation Plots Initiated in 2010 Treatment years 3 years of drought (2010-2012) Recovery years 3 years of recovery (2013-2015) Had rainout roofs in N, P, N&P, and control plots only Roofs went up ~April 15 and came off ~October 1 Collected ANPP and species composition data

9. Soil moisture was consistently reduced 77% 52% 20%

10. There were dramatic differences after 3 years of drought N&P PlotsControl Plots

11. Fertilizer treatment did not effect productivity resistance to drought but did affect resilience Drought: p < 0.001, N: p < 0.001 P: p < 0.001 D*N*P = 0.99 Drought: p = 0.09 N: p < 0.001 P: p < 0.001 D*N*P: p =0.01 Treatment Years Recovery Years

12. Fertilizer treatment affected species richness resistance to drought but not resilience Drought: p = 0.82 N: p = 0.002 P: p = 0.002 D*N*P: p = 0.55 D*N: p = 0.007 Drought: p = 0.712 N: p = 0.003 P: p = 0.002 D*N*P: p = 0.713 Treatment Years Recovery Years

13. Drought shifted community composition

14. Drought shifted community composition, but did not affect dispersion

15. During recovery the droughted communities were still different and had greater dispersion

16. All communities were surprisingly resistant and resilient to drought After drought there was greater variability among replicates that received nutrients

17. Thank You! Scott Collins, Melinda Smith, Mike from Home Depot, Patrick O’Neal, Jeff Taylor, Kim La Pierre, Kevin Wilcox, Dave Hoover, Erem Kazanıcoğlu, Nan and Ted Koerner, Jane and Joe Avolio, Rosemary Ramundo, and Amanda Kuhl

18. Questions?