1. Global Change Research from the Ground Up

2. 100011001200140013001600150018001700190020002100 1 0 4 3 2 5 Mean global temperature anomalies: last 1000 yrs indirect measures direct measures projections IPCC (2001)

3. Projected changes in average annual water runoff by 2050, relative to average runoff for 1961-1990 IPCC (2001)

5. Millennium Ecosystem Assessment (2005) Atmospheric nitrogen deposition

6. global environmental change elevated CO 2 warming precipitation nitrogen

7. Percentage change in average annual total Australian wheat yield for CO2 (levels of 700 ppm) IPCC (2001) rainfall change

8. global environmental change elevated CO 2 warming precipitation nitrogen

9. global environmental change elevated CO 2 warming precipitation nitrogen additive effects?

10. Jasper Ridge Global Change Experiment (1998-present)

11. Jasper Ridge, CaliforniaToronto, Ontario

12. Jasper Ridge, CaliforniaToronto, Ontario

13. Native perennial grasses (Danthonia californica and Nassella pulchra) Non-native annual grasses (Avena barbata, A. fatua, Bromus hordeaceus and Lolium multiflorum) Non-native forbs (Geranium dissectum, Erodium botrys and Crepis vesicaria) Native annual forbs (Hemizonia congesta and Epilobium brachycarpum) Annual grassland

14. The annual grassland as a model system 1.Small individuals = community level treatments in a small area 2.Annual lifecycle = treatments over multiple generations 3.Established plant and soil microbial communities 20 cm Year 1Year 2Year 3 Year 4

15. Jasper Ridge Global Change Experiment (1998-present) CO 2 - free air emitters: ~ 680 ppm

16. open top chamber for CO 2 delivery

17. Jasper Ridge Global Change Experiment (1998-present) NO 3 - - application: 7 g N m -2 y -1

18. Jasper Ridge Global Change Experiment (1998-present) heat - infrared lamps:1-2 °C

19. Jasper Ridge Global Change Experiment (1998-present) H 2 O - irrigation:ambient + 50%

20. NO 3 - H2OH2Oheatcontrol heat NO 3 - heat H 2 O NO 3 - H 2 O NO 3 - heat H 2 O 0 20 40 60 80 100 120 percent change in NPP ambient CO2 NO 3 - H2OH2Oheatcontrolheat NO 3 - heat H 2 O NO 3 - H 2 O NO 3 - heat H 2 O (Shaw et al. 2002)

21. NO 3 - H2OH2Oheatcontrol heat NO 3 - heat H 2 O NO 3 - H 2 O NO 3 - heat H 2 O 0 20 40 60 80 100 120 percent change in NPP ambient CO2 680 ppm CO2 NO 3 - H2OH2Oheat NO 3 - heat H 2 O NO 3 - H 2 O NO 3 - heat H 2 O (Shaw et al. 2002)

22. NO 3 - H2OH2Oheat NO 3 - heat H 2 O NO 3 - H 2 O NO 3 - heat H 2 O (Shaw et al. 2002)

23. Dukes et al. (2005)

25. Fire! July 2003

26. Net primary production N N N N

27. Annual grasses N N NN NO 3 - *** B * NO 3 - X CO 2 **

28. Herbivore effects Slug feeding preferences and abundance in plots explain over 50% of variation in productivity

29. Lessons learned from the JRGCE: 1.Global change will result in changes in ecosystem productivity and plant species composition 2. Unforeseen interactions of climate change with nitrogen pollution and elevated CO 2 Wildcards: influence of disturbance and herbivores

30. Davis (1981)

31. Invasive species

32. My current research: Winter warming and N deposition

33. Agricultural field near London, ON

34. continuous snow cover Agricultural field near London, ON

35. Effects of freezing on soil soil aggregate disruption microbial lysis plant litter breakdown root lysis

36. leaching losses of C, N and P CO 2, N 2 O Effects of freeze-thaw soil aggregate disruption microbial lysis plant litter breakdown root lysis

37. Long-term warming and N deposition experiment

38. Objective: To explore the interactive effects of climate warming and increased atmospheric N deposition on a temperate ecosystem - specific emphasis on winter warming

39. Grasses: Poa pratensis (Kentucky blue grass) – perennial Bromus inermis (smooth brome) – perennial Forbs: Solidago altissima (tall goldenrod) – perennial Cirsium arvense (Canada thistle) – perennial Medicago lupulina (black medick) – annual/perennial, legume Melilotus alba (white sweet-clover) – annual/perennial, legume Lotus corniculatus (bird’s foot trefoil) – perennial, legume

40. 110 V AC soil surface 150 W ceramic infrared heater reflector weatherproof lightbulb socket metal pipe Heating bracket (heats 3 plots) Side view: height-adjustable bracket

41. 1 m Block design 1 plot = dummy heater = IR heater (n=10)

42. 1 m 1 plot = dummy heater = IR heater heated- all year heated- late-fall to spring

43. 1 m 1 plot = dummy heater = IR heater heated- all year heated- late-fall to spring N N N

44. Soil monitoring - soil temperature - 2 and 5 cm depth - hourly - volumetric water content - 0-15 and 0-30 cm depth - hourly

46. - PTFE/quartz lysimeters - no retention/contamination - durable - 50 cm depth Soil water collection

47. Terry Bell Soil microbial enzyme activities and microbial community structure Jennifer Hutchison Primary production and plant species composition Paul Mensink and Eric Moise Invasive wood snails Michelle Turner Nitrogen leaching losses and net mineralization

49. Cirsium Lotus

50. NDVI - Plant Greenness

52. Net Ecosystem Exchange