Impacts of acid rain and ozone on vegetation in the Greater Mekong Sub region

1. lisa.emberson@sei.se Impacts of acid rain and ozone on vegetation in the Greater Mekong Sub region Lisa Emberson Patrick Büker, Tim Morrissey, Kevin Hicks, Johan Kuylenstierna, Steve Cinderby, Mike Ashmore, David Simpson, Juha-Pekka Tuovinen, Mark Zunckel, Miles Sowden, Barabara Badu, Vanessa Walsh

2. lisa.emberson@sei.se Talk outline Why worry about air pollution impacts on vegetation ? Air pollution risk assessment methods for application in GMS : - Modelling methods - Experimental methods - Bio-monitoring methods Application incorporating additional stresses ? - Climate change - Hydrological stress

3. lisa.emberson@sei.se Talk outline Why worry about air pollution impacts on vegetation ? Air pollution risk assessment methods for application in GMS : - Modelling methods - Experimental methods - Bio-monitoring methods Application incorporating additional stresses ? - Climate change - Hydrological stress

4. Air pollutant Gas, particle, aerosol, solute Stomatal flux/uptake/deposition Non-stomatal flux/uptake/deposition Direct External plant surfaces Soil Indirect lisa.emberson@sei.se Why worry about air pollution impacts on vegetation ?

5. lisa.emberson@sei.se Why worry about air pollution impacts on vegetation ? * At low concentrations can stimulate growth via fertilization effect ** Dependant upon chemical composition of particles

6. lisa.emberson@sei.se Why worry about air pollution impacts on vegetation ? * At low concentrations can stimulate growth via fertilization effect ** Dependant upon chemical composition of particles

7. Why worry about air pollution impacts on vegetation ? Decline of Veitch’s silver fir and maries fir. Japan (courtesy of T. Izuta)

8. Annual average pH of P Rodhe et al. 2002 Kuylenstierna et al. 2001 Soil sensitivity to acidic deposition

9. lisa.emberson@sei.se Observational evidence of soil acidification in China similar to Europe Change in soil pH 1960 – 1994 at Zhurongfeng in S. China Dai et al. 1998 The decrease in soil pH between 1927 to 1982-83 in a beech and spruce forest in southern Sweden (Hallbäcken and Tamm, 1985) No real evidence in other parts of Asia

10. Why worry about air pollution impacts on vegetation ? O3 injury to rice, Pakistan (courtesy of A. Wahid)

11. Europe 36.6 ppb ± 4.2 United states 38.7 ppb ± 4.9 South East Asia 31.5 ppb ± 4.4 Current surface ozone in 2000 Dentener et al. (2006)

12. CLE2000 – CLE2030 Europe +1.8 ± 1.5 United states +1.3 ± 2.4 South East Asia +3.8 ± 0.7 Δ in surface ozone between 2000 and 2030 current legislation scenario Dentener et al. (2006)

13. lisa.emberson@sei.se Talk outline Why worry about air pollution impacts on vegetation ? Air pollution risk assessment methods for application in GMS : - Modelling methods – Acid Deposition - Experimental methods - Bio-monitoring methods Application incorporating additional stresses ? - Climate change - Hydrological stress

14. lisa.emberson@sei.se • What methods exist to estimate risk? • Critical Load approach: deposition compared to threshold (CL) • 2. Dynamic models – limited application except in China for some sites

15. lisa.emberson@sei.se Exceedance of critical loads a static expression of risk but is it real? time dimension issue: acidification has not occurred for long enough for clear impacts to be seen? Estimated exceedance of acidification CL of S only (Kuylenstierna et al. 2000)

16. lisa.emberson@sei.se “Serious acidification effects not likely to occur in next few decades in Asia except in China” Henning Rodhe

17. lisa.emberson@sei.se Estimates time development of acidification as a function of continued acidic deposition and variation in soil sensitivity over time Hicks et al. in prep

18. lisa.emberson@sei.se Talk outline Why worry about air pollution impacts on vegetation ? Air pollution risk assessment methods for application in GMS : - Modelling methods - Experimental methods – surface ozone - Bio-monitoring methods Application incorporating additional stresses ? - Climate change - Hydrological stress

19. Response Dose Assessing O3 impacts to species/ cultivars

20. Controlled exposure • Free Air Concentration Enrichment (FACE) • Temporary chambers • Open Top Chambers • Solardomes • Indoor fumigation chambers / glasshouses Disturbance Experimental Methods • individual pollutants & pollutant combinations • establish dose response relationships • pollutant interactions with other stresses

21. Controlled exposure • Free Air Concentration Enrichment (FACE) • Temporary chambers • Open Top Chambers • Solardomes • Indoor fumigation chambers / glasshouses Disturbance Experimental Methods • individual pollutants & pollutant combinations • establish dose response relationships • pollutant interactions with other stresses

23. Response Yield Nutritional quality Visible injury Dose Concentration Flux Assessing O3 impacts to species/ cultivars

24. (53 ppb) * Annual mean * 7hr annual mean * 7hr growing season mean * AOT40

25. 7 hr mean dose response relationships for different species including rice cf. Wang & Mauzerall 2004

26. AOT40 relationship with wheat (Triticum aestivum) grain yield (Fuhrer, 1996) • Most robust AOT40 relationship • 17 experiments, 6 countries, 10 growing seasons, 10 cultivars • Critical Level : AOT40 of 3, 000 ppb.h. corresponding to 5% yield loss (99% • confidence) calculated over a 3 month growing period

27. lisa.emberson@sei.se Talk outline Why worry about air pollution impacts on vegetation ? Air pollution risk assessment methods for application in GMS : - Experimental methods - Modelling methods – surface ozone - Bio-monitoring methods Application incorporating additional stresses ? - Climate change - Hydrological stress

28. Dose-Response Relationships How can we estimate air pollution impacts?

29. Modelling methods 3 month AOT40 simulations calculated with the MATCH model Engardt pers. comm., Emberson et al. in press

30. lisa.emberson@sei.se Modelling methods BUT Are these areas identified as being at risk from ground level ozone correct? How good is the provisional risk assessment modelling?

31. Modelling methods How good is the regional ozone concentration data? What are the receptors most at risk? How well can AQGs protect local species and varieties?

32. lisa.emberson@sei.se Talk outline Why worry about air pollution impacts on vegetation ? Air pollution risk assessment methods for application in GMS : - Experimental methods - Modelling methods - Bio-monitoring methods – surface ozone Application incorporating additional stresses ? - Climate change - Hydrological stress

33. Bio-monitoring Bio-monitoring and Chemical Protectant Studies Buse et al. 2002/2003 • Established bio-indicator in Europe and North America • Sensitive and resistant clones so can assess magnitude of air pollution impacts on visible injury & biomass.

34. Structural formula for N-(2-(2-oxo-1-imadazolidinyl)ethyl)-N’-phenylurea abbreviated as EDU for ethylenediurea Bio-monitoring Bio-monitoring and Chemical Protectant Studies Pakistan soybean cv. NARC-1 showing protective effect of EDU at a roadside rural site in Lahore, Pakistan (photo courtesy of A. Wahid) EDU suppresses acute and chronic ozone injury on a variety of plants under ambient O3 conditions (Godzik & Manning, 1998)

35. Bio-monitoring • All Bio-monitoring sites: • Microloggers for ToC & RH % (30 min) • Ozone passive samplers (2 week) • At select sites: • Solar radiation, photosynthetically active radiation (PAR) • Continuous ozone monitoring (hourly) • Soil water content • Plant physiological parameters • e.g. Photosynthesis, stomatal conductance, leaf area index, biochemical analysis (e.g. heavy metals, protein content….)

36. Europe & North America e.g. Maize staple Pulse EDU chemical protectant study Wheat Mung bean Southern Africa South Asia 5 sites 6 sites India, Pakistan, Sri Lanka, Bangladesh, Nepal South Africa, Botswana, Zimbabwe, Mozambique Zambia, Tanzania Bio-monitoring RAPIDC Project funded by Sida “Regional Air Pollution in Developing Countries” Provisional Risk Assessment Clover clone bio-monitoring

37. Bio-monitoring How good is the regional ozone concentration data? Passive samplers, O3 monitors What are the receptors most at risk? Local agricultural expertise How well can AQGs protect local species and varieties? Bio-monitoring evaluation of damage occurring within and outside provisionally assessed risk areas

38. Bio-monitoring How good is the regional ozone concentration data? Passive samplers, O3 monitors What are the receptors most at risk? Local agricultural expertise How well can AQGs protect local species and varieties? Bio-monitoring evaluation of damage occurring within and outside provisionally assessed risk areas

39. Dose modifiers Climate Precipitation patterns Sunshine hours Higher temperatures Atmospheric humidity Soil Moisture deficit Vegetation sensitivity Cropping patterns (growing season) Pollutant dispersion O3 formation Flux Modelling methods • Species type / cultivar • Agronomic practices • Irrigation • Fertilizer • Breeding programmes (selecting increased / reduced crop sensitivity)

40. Assessing O3 impacts to species/ cultivars AOTx “Concentration” AFstY “Flux” Surface Resistance Rsur

41. lisa.emberson@sei.se Bio-monitoring The Air Pollution Crop Effect (APCEN) network • Advise on methodological development • To capacity build in the regions –provide technical support to the bio-monitoring campaigns • To help in translation of science to policy RAPIDC Regional air pollution in developing countries

42. The APCEN Network

43. The APCEN network 2nd APCEN workshop held in Stellenbosch, South Africa 2006

44. lisa.emberson@sei.se Talk outline Why worry about air pollution impacts on vegetation ? Air pollution risk assessment methods for application in GMS : - Experimental methods - Modelling methods - Bio-monitoring methods Application incorporating additional stresses ? - Climate change - Hydrological stress

45. Why worry about surface ozone concentrations ? Δ in surface ozone between 2030clim change and 2030 current legislation scenario and projected 2030 climate South East Asia CLE2030c – CLE2030 -0.2 ± 0.6 Dentener et al. (2006)

46. Fuhrer et al. 2005

47. O3 • Resulted in 20% loss in seed yield • Results suggest even greater losses than those previously predicted by closed chamber studies O3 • FACE soybean (glycine max) experiment • Increased O3 concentrations over two growing seasons by 23 % - mimicking projections for 2050 Morgan et al. 2006

48. Phenology ToC PAR VPD SMD Rsto = 1/ (gmax * fphen * flight * max {fmin, (ftemp * fVPD * fSWP)}) Gmax mmol O3 m-2 s-1 *

49. lisa.emberson@sei.se Talk outline Why worry about air pollution impacts on vegetation ? Air pollution risk assessment methods for application in GMS : - Experimental methods - Modelling methods - Bio-monitoring methods Application incorporating additional stresses ? - Climate change - Hydrological stress

50. Future applications ? Modelled ozone concentrations across Southern Africa Zunckel et al 2004