FACTOR-ANALYSIS OF ATMOSPHERIC TRACE-ELEMENT DEPOSITION DATA IN THE NETHERLANDS OBTAINED BY MOSS MONITORING

Monte Carlo-Assisted Factor Analysis has been applied to a data set of trace element concentrations in samples of the moss species Pleuroziu m schreberi, collected in 1992 from 66 locations in the Netherlands. A Monte Carlo approach was used to give more insight in the uncertainti es and significance levels of the factor analysis results. Using a sel ection of 23 elements, factor analysis enabled the identification of 8 significant pollution source types. Two source types were assumed to be related to the influence of foliar leaching from higher plants. The remaining source types were found to correspond with the major source types obtained in earlier biomonitoring surveys in the Netherlands us ing lichen and bark, i.e. crustal material, sea aerosol and various ty pes of industrial pollution sources, associated with metallurgical ind ustries, refuse incineration and oil combustion or processing of oil p roducts. The contribution of the industrial pollution sources appeared to have decreased between 1987 and 1992.