You are here:
Canopy Level Emissions of 2-methyl-3-buten-2-ol, monoterpenes, and sesquiterpenes from a Pinus taeda Experimental Plantation
Citation:
Geron, C., R. Daly, R. Arnts, A. Guenther, AND F. Mowry. Canopy Level Emissions of 2-methyl-3-buten-2-ol, monoterpenes, and sesquiterpenes from a Pinus taeda Experimental Plantation. SCIENCE OF THE TOTAL ENVIRONMENT. Elsevier BV, AMSTERDAM, Netherlands, 565:730-741, (2016).
Impact/Purpose:
This paper describes an emission inventory and model validation study for Organic air emissions from the worlds most important commercial tree species.
Description:
Emissions of biogenic volatile organic compounds (BVOC) observed during 2007 from a Pinus taeda experimental plantation in Central North Carolina are compared with model estimates from MEGAN 2.1. Relaxed Eddy Accumulation (REA) estimates of 2-methyl-3-buten-2-ol (MBO) fluxes are a factor of 3-4 higher than model estimates. MEGAN2.1 monoterpene emission estimates were approximately a factor of two higher than REA flux measurements. MEGAN2.1 β-caryophyllene emission estimates were within 60% of growing season REA flux estimates, but were several times higher than REA fluxes during cooler, dormant season periods. The sum of other sesquiterpene emissions estimated by MEGAN2.1 was several times higher than REA estimates throughout the year. Model components are examined to understand these discrepancies. Summertime LAI (and therefore foliar biomass) is a factor of two higher than assumed in MEGAN for the Pinus taeda default. Increasing the canopy mean MBO emission factor from 0.35 to 1.0 mg m-2 hr-1 also reduces MEGAN2.1 vs flux differences. This increase is within current emission factor uncertainties. The algorithm within MEGAN which adjusts isoprene emission estimates as a function of the previous 24 hour’s temperatures and light seems to also improve seasonal MEGAN MBO correlation with REA fluxes. Including the effects of the previous 240 hours, however, seems to degrade temporal model correlation with fluxes.
