B. Papp szerk.: Studia Botanica Hungarica 30-31. 1999-2000 (Budapest, 2000)

Csontos, Péter, Lőkös, László; Molnár, Katalin: Numerical analysis of lichen zones in Komárom, NW Hungary

cated "desert zone" (where the epiphytic lichens are missing), one or more "struggle zones" (where there is a transitional lichen vegetation), and usually far from the pollution sources the "normal zone" (where the lichen vegetation appears to be almost natural). Certain kinds of indices (IP, IAP, lichen biodiversity index, etc.) were applied for confirmation of the borders of the zones (TRASS 1968, LEBLANC and DE SLOOVER 1970, NIMIS et al. 1991 ), but for individual cities these were not supported by numerical analyses yet. Preparation of the lichen map of Komárom (MOLNÁR 1999) made it possible to establish lichen zones of the town and its surroundings. The central desert zone seemed to be missing. Two struggle zones and the normal zone were clearly visible. The border of the inner struggle zone almost coincides with the densely built-up area of the town. Based on the species distribution data, these impressions of zone boundaries are supported by multivariate numerical analysis in this paper. MATERIAL AND METHODS Altogether, 630 records of 50 (20 epiphytic and 30 saxicolous) lichen species were collected from 84 localities within the administrative boundary of Komárom (NW Hungary) (Fig. 1) between October, 1997 and April, 1999. The majority of the individuals were found on tree barks and on stones. Soil inhabiting lichens were almost missing, only found occasionally on small soil patches in wall gaps of some very old buildings {e.g. Fortress Igmánd). Specimens were identified and deposited in the lichen herbarium of the Hungarian Natural History Museum (Budapest, BP), thus serving as a basic reference of this study. Fig. 1. Location of the study area in Hungary.