scope:

This guideline replaces the guideline VDI 3792 Part 5:1991-06. It serves as an instruction to the passive biomonitoring of pollution impacts on plants in regions ("area related") and in the surroundings of emission sources ("source-related"), whereby both the recording of chronic effects and the recording of malfunctions of operations can be the purpose. Air pollution effects according to guideline VDI 2310 Part 1 is given, if the substance concentration determined in a specimen significantly exceeds the natural concentration.

For the determination of a pollution impact both the normal value, that is the value of the "natural" concentration, and its statistical variation are essential. Examples for normal values of nutrient element concentrations of spruce needles (Picea abies L.) are specified in VDI 3957 Part 5 and in [18; 19] whereas in [20; 21] also data concerning some heavy metals and persistent organic/pollutants (POPs) in coniferous and deciduous trees are given. Reference values for beech and poplar leaves as well as for spruce and pine shoots are currently published by the German Environmental Specimen Bank [14]. Further basic information concerning the vertical and horizontal nutrient and pollutant distribution in coniferous and deciduous trees as well as references to methods development are given in [3; 22 to 25]. A detailed description of the statistical variation occurring in each of the individual process steps and under methodical modifications is presented in [26].

In the following criteria for the selection of the monitoring sites and the tree species are specified, and methods of sampling and sample preparation as well as methods on the verification of pollution impacts are described. Concerning the phytotoxic effects of airborne pollutants on plants refer to the publications [27 to 30].