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Research Articles
Free-Air Fumigation of Mature Trees
A Novel System for Controlled Ozone Enrichment in Grown-Up Beech and Spruce Canopies
Herbert Werner; Peter Fabian
Corresponding author:: Dr. Herbert Werner, Technical University of Munich, Dept. of Ecology, Bioclimatology and Pollution Research, Am Hochanger 13, D-85354 Freising-Weihenstephan, Germany; e-mail: werner@met.forst.tu-muenchen.de
DOI: http://dx.doi.org/10.1065/espr2001.02.053 - - - A novel system for continuous and controlled free-air fumigation of mature tree canopies with ozone is described. Ozone generated from oxygen is diluted with air in a pressurized tank and conducted into the canopies by a system of 100 PTFE tubes hanging down from a grid fixed above the crowns. With 45 calibrated outlets per tube providing a constant flow of 0.3 l/min each, a total volume of about 10*10*15 m3 comprising 5 beech and 5 spruce canopies is fumigated. The spatial ozone distribution in the fumigated volume as well as surrounding reference tree canopies is controlled by continuous measuring instruments installed at 4 levels and a dense array of passive samplers. The system will later be used for CO2 fumigation as well. Results of the first year of continuos operation, with 2 * ambient ozone levels having been achieved, are reported. | | Keywords: Beech; FACE; free-air CO2 enrichment (FACE); fumigation; ozone; passive samplers; research articles; spruce; stress |
9 ESPR (2) 117-121 (2002)
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