Annual rates of deposition of polycyclic aromatic hydrocarbons in different forest ecosystems

Using the flux balance of the forest canopy of a beech and a spruce stand annual rates of total deposition — divided into precipitation and interception deposition — were derived for 4 polycyclic aromatic hydrocarbons (PAH). The deposition of PAH is in general higher under spruce because of higher rates of interception deposition as compared to beech. The rate of interception deposition of the various PAH compounds (3.4-Benzopyrene, Indeno (1,2,3-cd)pyrene,1.12 Benzoperylene, Fluoranthene) are significantly different. Substantial amounts of PAH are transferred to the soil by litterfall, which indicates adsorption of PAH on leaf and needle surfaces. The storage of PAH in the soil is equivalent to 34 to 48 yr of the actual deposition for 3.4 Benzopyrene and Indeno (1,2,3-cd)pyrene and is equivalent to 14 to 26yr of actual deposition for the amount of 1.12 Benzoperylene and Fluoranthene in the soil.