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The emission of isoprene from the leaves of forest trees is a fundamental component of biosphere-atmosphere interactions, controlling many aspects of photochemistry in the lower atmosphere. As almost all commercial agriforest species emit high levels of isoprene, proliferation of agriforest plantations has significant potential to increase regional ozone(More)
Biogenic volatile organic compounds (BVOC) contribute significantly to the formation of ozone and secondary organic aerosol (SOA). The Model of Emissions of Gases and Aerosols from Nature (MEGANv2.02) is used to estimate emissions of isoprene, monoterpenes (MT), and sesquiterpenes (SQT) across the United States. Compared to the Biogenic Emission Inventory(More)
The global emissions of isoprene are calculated at 0.5 • resolution for each year between 1995 and 2006, based on the MEGAN (Model of Emissions of Gases and Aerosols from Nature) version 2 model (Guenther et al., 2006) and a detailed multi-layer canopy environment model for the calculation of leaf temperature and visible radiation fluxes. The calculation is(More)
Tropical forests are an important global source of volatile organic compounds (VOCs) and other atmospheric trace gases. The high biodiversity in tropical rainforests complicates the extrapolation of biogenic volatile organic compound (BVOC) emissions from leaf-level measurements to landscape and regional or global scales. In Amazônia, a 5 significant(More)
Leaves of some plants emit isoprene, a volatile hydrocarbon. This is formed by a novel chloroplastic isoprenoid biosynthetic pathway, the 1-deoxy-D-xylulose-5-phosphate pathway. The thermoprotection hypothesis suggests that isoprene protects thylakoids from damage at high temperatures. In this article, we discuss the most recent discoveries about the(More)
Cottonwood (Populus deltoides Bartr. ex Marsh.) trees grown for 9 months in elevated carbon dioxide concentration ([CO2]) showed significant increases in height, leaf area and basal diameter relative to trees in a near-ambient [CO2] control treatment. Sample trees in the CO2 treatments were subjected to high and low atmospheric vapor pressure deficits (VPD)(More)
T he importance of land surface properties in controlling the exchanges of energy, water, and momentum with the atmosphere, and thus in infl u-encing local and regional climate, is well recognized. Important land surface characteristics—including albedo, surface roughness, latent and sensible heat fl uxes, and rates of evapotranspiration—aff ect the way in(More)
This manuscript includes findings from field and numerical modeling investigations designed to quantify the degree and rates of biogenic hydrocarbon chemical processing within and above a mixed deciduous forest in the southeastern United States. The study site was under the influences of nitrogen oxide and hydrocarbon emissions from suburban automobile(More)
Hourly data for concentrations and uxes of CO 2 at 30 m in Harvard Forest Petersham, Massachusetts are analyzed using linear modeling to obtain regionally representative C O 2 concentrations at a continental site. The time series is decomposed into contributions due to regional combustion, local canopy exchange, monthly average regional biotic exchange as(More)