[Bartolome2007] "Mass scans from a proton transfer mass spectrometry analysis of air over Mediterranean shrubland browsed by horses.",
J Environ Biol
, vol. 28, no. 4: Unitat Ecofisiologia CSIC-CREAF CREAF, Edifici C, Universitat AutÃ³noma de Barcelona, Bellaterra-08193 Barcelona, Spain. firstname.lastname@example.org, pp. 697–700, Oct, 2007.
Plants usually emit large amount and varieties of volatiles after being damaged by herbivores. However, analytical methods for measuring herbivore-induced volatiles do not normally monitor the whole range of volatiles and the response to large herbivores such as large mammals is much less studied than the response to other herbivores such as insects. In this paper we present the results of using a highly sensitive proton transfer reaction-mass spectrometry (PTR-MS) technique that allows simultaneous monitoring of leaf volatiles in the pptv range. The resulting mass scans in air over Mediterranean shrubland browsed by horses show 70 to 100% higher concentrations of the masses corresponding to mass fragments 57, 43 and 41 (mostly hexenals, acetone and acetic acid) than scans over control non-browsed shrubland. These compounds are biogeochemically active and they are significant components of the volatile organic carbon found in the atmosphere. They influence the performance of living organisms and, the chemical and physical processes of Earth's atmosphere.
[Filella2007] "Volatile organic compounds emissions in Norway spruce (Picea abies) in response to temperature changes",
, vol. 130, no. 1: Wiley Online Library, pp. 58–66, 2007.
Volatile organic compound (VOC) emissions from Norway spruce (Picea abies) saplings were monitored in response to a temperature ramp. Online measurements were made with a proton transfer reaction – mass spectrometer under controlled conditions, together with plant physiological variables. Masses corresponding to acetic acid and acetone were the most emitted VOCs. The emission rates of m137 (monoterpenes), m59 (acetone), m33 (methanol), m83 (hexanal, hexenals), m85 (hexanol) and m153 (methyl salicylate, MeSa) increased exponentially with temperature. The emission of m61 (acetic acid) and m45 (acetaldehyde), however, increased with temperature only until saturation around 30°C, closely following the pattern of transpiration rates. These results indicate that algorithms that use only incident irradiance and leaf temperature as drivers to predict VOC emission rates may be inadequate for VOCs with lower H, and consequently higher sensitivity to stomatal conductance.