Correlation patterns of metals in the epiphytic moss Hypnum cupressiforme in Bavaria

Since 1981, the Bavarian State Office for Environmental Protection (LfU) ha s been operating a bioindication network of epiphytic mosses Hypnum cupress iforme located on a regular grid with distances 16 km, in order to observe immission-derived metal accumulation in plant material. About 300 specimens are collected yearly (since 1991 every second year) at the end of the grow th period, and the concentration of trace metals is determined. In order to gain insight into predominant sources of metal pollution in Bavaria, corre lation patterns between Al, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Cd, Sb, Hg, and Pb are analyzed by Principal Component Analysis. Detailed results are p resented for the 1984 and 1995 data. At least 80% of the variance can be ex plained by five components. The following factors are extracted from both d ata sets by varimax rotation: factor 1 with similar loadings of Al, Ti, V, Cr, Fe, and As; factor 2 representing Cd and Zn; factor 3 with loadings of Sb, Pb, and Cu; factor 4 representing Mn; factor 5 being nearly identical w ith the Hg variable. For comparison, published region-specific correlation matrices from the 1991 moss survey performed by the German Federal Environm ental Agency (UBA) - observing epigeic mosses Pleuronium schreberi - were s ubmitted to Principal Component Analysis. With respect to the first factor, our 1991 results from Bavaria are similar to those from the Southern forme r GDR, but different from those from Western Germany (including Bavaria). P ossible common and specific sources are discussed. (C) 2000 Elsevier Scienc e Ltd. All rights reserved.