Nitrogen dioxide (NO2) uptake by vegetation controlled by atmospheric concentrations and plant stomatal aperture

摘要: Abstract Nitrogen dioxide (NO 2 ) exchange between the atmosphere and five European tree species was investigated in laboratory using a dynamic branch enclosure system (consisting of two cuvettes) highly specific NO analyzer. measurements were performed with sensitive gas phase chemiluminescence detector combined (photolytic) converter, both from Eco-Physics (Switzerland). This detection excluded bias other nitrogen compounds. Investigations at light intensities (Photosynthetic Active Radiation, PAR, 450 900 μmol m −2  s −1 concentrations 0 5 ppb. Ambient parameters (air temperature relative humidity) held constant. The data showed dominant uptake by respective under all conditions. results did not confirm existence compensation point within 95% confidence level, though we cannot completely exclude emission very low atmospheric concentrations. Induced stomatal stricture, or total closure, changing conditions, as well application plant hormone ABA (Abscisic Acid) caused corresponding decrease uptake. No loss to surfaces observed closure dependent differences rates could be clearly related behavior.