A Veszprém Megyei Múzeumok Közleményei 12. (Veszprém, 1973)

Dr. Debreczy Zsolt: A Balaton-felvidéki Péter-hegy és környéke cönológiai vizsgálata

level. The average species number of the grass level is 46, its moss level is the poorest among the surrounding associations (xerotherm species are photophilous in nature!). Coenologically Omo-Cotinetalia 13%, Querceta and Festuco-Brometea species are with similar ratio (40" iO characterize this association. The sub-Mediterranean and Pontian character is strong (39%). The Hungarian varieties (JAKUCS 1961) analysed by relative coefficients show that the most striking differences have been displayed by the differential Festuco-Brometea species of the contiguous associations. Pubescent oak forest (Ото-Quercetum pannonicum). The zonal nature of this association in the Balaton upland has recently been established. After a detailed analysis, the zonal forest was divided into subassociations starting from the southerly closed oak forests (1. coronilletosum, 2. petraeetosum, DEBRECZY 1968). The two subassociations are close to each other as regards Querceta species, but they clearly differ in view of Querco-Fagea and Festuco-Brometea species, and with lliis, the ratio of the continental and sub-Mediterranean on the one hand, and the European and Eurasian species on the other. Oak forests with hornbeam groves {Quer co-Car pine,v tum pannonicum). This is a mesophilous association in the percentual ratio of Querceta is rather high (22.5%), Besides the Carpinion (13%), Fagetalia, the CarpinoFagatea (19%) and Querco-Fagatea (38%) elements, the percentual ratio of Querceta is rather high (22,5%), which reveals that the nature of the association is subMediterranean (16%). This, howewer, does not attach it to the mesophilous forest species belonging to the sub-Mediterranean Fagion illyricum the Helleboro (dumetorum)-Carpinetum and Asperulo taurinae-Carpinetum association, because here the 77%, of the subMediterranean species originate from the surrounding oak forest comprising Querceta elements. Furthermore, the study briefly treats the transitional belts between the Orno-Quercetum and the QuercoCarpinetum which comprises Quercetum-petraeae-cerris and the relic Carex alba patches where Veronica officinalis and Melampyrum pratense acidophilous species occur on the acidic areas. These species do not appear on the limestone areas, their expansion into this region may be explained by vegetation historical causes (Atlantic phase). Zsolt Debreczy 220