Emissions of Volatile Organic Compounds by Plants Carbon Metabolism and Atmospheric Chemistry Kolby...
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- Slide 1
- Emissions of Volatile Organic Compounds by Plants Carbon
Metabolism and Atmospheric Chemistry Kolby Jardine Amazon-PIRE
Field Course June 2010
- Slide 2
- Composition of the Atmosphere Gases
- Slide 3
- What are VOCs? Atmospheric Concentrations < 20 ppb
- Slide 4
- Dominant primary VOC sources in the Atmosphere Biomass Burning
Urban/Industrial Emissions Biogenic Emissions VOC: volatile organic
compound e.g. hydrocarbons
- Slide 5
- From www.igac.noaa.gov Atmospheric Impacts of VOCs 1)Climate
2)Air Quality
- Slide 6
- Why the interest in BVOCs? Reactive Aerosols Biogenic VOCs
Anthropogenic VOCs
- Slide 7
- Organic Aerosol TRACE GASES oxidize Ozone H 2 CO CO CH 4
Secondary Organic Aerosol Isoprene Monoterpenes Sesquiterpenes
Oxygenated VOC
- Slide 8
- Simplified Catalytic Cycle of Tropospheric Ozone Production
Players: VOC: volatile organic compounds NO x : nitrogen oxides RO
2: peroxy radicals hv: radiation RO 2 (HO 2 ) ROVOC emissions OH
O2O2 Fuel NONO 2 NO x emissions OH HNO 3 O2O2 hv Ozone Catalyst
fossil fuel combustion biomass burning (soil, lightning) O*
- Slide 9
- How Many Species are Produced during the Oxidation of
Hydrocarbons? Aumont et al., ACPD, 2005 Heptane: 10 5 10 6
intermediates >10 6 reactions Isoprene: 10 4 intermediates
>10 4 reactions O 3 + hv O( 1 D) + O 2 O( 1 D) + H 2 O OH + OH
OH The Detergent of the Atmosphere During the 18th century
engineers already knew that coal combustion would release CO as a
toxic substance. They estimated that within ~1000-2000 years the
atmosphere would fill up with high enough levels of CO so that any
life on the planet would die! Luckily this wont happen due to the
presence of OH!
- Slide 10
- Tower-based flux meas. systems Years Days Hours TIME SCALE
SPATIAL SCALE Leaf Canopy LandscapeRegional/global Enclosure flux
meas. systems Analysis using ambient concentrations, isotopes and
oxidation products Satellite data (e.g. HCHO) Aircraft and
blimp-based flux measurement systems Process studies Tools for
Investigating Trace Gas Fluxes Seconds Regional
Characterization
- Slide 11
- Measurement techniques
- Slide 12
- Amazon VOCs Emitted from Vegetation >1000 compounds
identified tropics: 100s species / ha Image from
ksuweb.kennesaw.edu
- Slide 13
- Ray Fall 1999 Volatile Metabolite Emissions from Plants
1)Environmental Stresses (desiccation, UV light, oxidants) 2)
Reproduction and growth 3) Phytohormones (semiochemicals) 4)
Biological stresses (herbivores) 5) Primary carbon and energy
metabolism
- Slide 14
- Primary Carbon Metabolism in Plants RUBISCO PEP carboxylase
Respiration Photorespiration Fermentation CO 2 Photosynthesis Are
VOC emissions related to these processes?
- Slide 15
- Pyruvic acid; the link between primary and secondary carbon
metabolism Ethanol Acetaldehyde Acetic Acid Pyruvic Acid Acetone
Isoprene Sesquiterpenes Monoterpenes
- Slide 16
- Slide 17
- Slide 18
- Response of Isoprene Emissions to Temperature Guenther et al.
empirical algorithms
- Slide 19
- Response of Isoprene Emissions to Light
- Slide 20
- Response of Isoprene Emissions to Atmospheric CO2
Concentrations
- Slide 21
- F = g*C, where C = [isoprene] i [isoprene] a atmosphere Leaf
[isoprene] a production [isoprene] i [isoprene] a production
[isoprene] i [isoprene] a production [isoprene] i
- Slide 22
- F = g*C, where C = [AA] i [AA] a [AA] a atmosphere Leaf
consumption production [AA] i consumption production [AA] i
- Slide 23
- Summary of Biosphere-Atmosphere Feedbacks From Pasifico et al.,
2009
- Slide 24
- Thanks! Paulo Artaxo (University of Sao Paulo) Trina Shartsis
(University of Arizona) Scott Saleska (University of Arizona)
Travis Huxman (University of Arizona) Angie Jardine (University of
Arizona) Alex Guenther (NCAR) Thomas Karl (NCAR) Peter Harley
(NCAR)