B. Papp szerk.: Studia Botanica Hungarica 33. 2002 (Budapest, 2002)

Dobolyi, Konstantin: Studies of vegetation dynamics on the rock grasslands in Csíki-hegyek (Budaörs, Hungary)

changed and stabilised (secondary rock steppes and grasslands). Today the main tendencies of change of vegetation are the spontaneous spreading of (mostly native) shrubs and degradation caused by the growing tourism. Results of this study have pointed out first of all the main trends and degrees of site degradation. Some evidence of the latter in botanical terms: - decreasing proportion of specialists, - decreasing average naturalness values, - increasing proportion of the higher nitrogen preference categories (in Farkas-hegy). In spite of the undesirable processes the studied sites are valuable and deserve protection. Some facts justifying the extremely high natural value of these rock grasslands: - high number of plant species, - high proportion of special floral elements and endemic species, - high proportion of specialists, - high average naturalness values, - low proportion of weeds (including nitrophilous ones). In the interest of protection of natural values of the investigated sites (and their surrounding areas) a reasonable controlling and limitation of tourism seem to be necessary and unavoidable. REFERENCES BARTHA, S., RÉDEI, T., SZOLLÁT, OY., BÓDIS, J. and MUCINA, L. (1998): Északi és déli kitettségű dolomitsziklagyepek térbeli mintázatainak összehasonlítása. (Compositional diversity and fine-scale spatial patterns of dolomite grasslands on contrasting slopes). - In: CSONTOS, P. (ed.): Sziklagyepek szünbotanikai kutatása. [Synbotanical study of rock grasslands]. - Scientia Kiadó, Budapest, pp. 159-182. BORHIDI, A. (1993): A magyar flóra szociális magatartás típusai, természetességi és relatív ökológiai értékszámai. (Social behaviour types of the Hungarian flora, its naturalness and relative ecological indicator values). - Janus Pannonius University, Pécs, 95 pp. BORHIDI, A. (ed.) (1996): Critical revision of the Hungarian plant communities. - Janus Pannonius University, Pécs, 138 pp. BORHIDI, A. and SÁNTA, A. (ed.) (1999): Vörös könyv Magyarország növénytársulásairól 1-2. [Red book of the plant communities of Hungary]. - Természetbúvár Alapítvány Kiadó, Budapest, pp. 362, 404. DEBRECZY, ZS. (1966): Die xerothermen Rasen der Péter- und Tamás-Berge bei Balatonarács. Annls hist.-nat. Mus. nam. hung. 58: 223-241. DEBRECZY, ZS. (1973): A Balaton-felvidéki Péter-hegy és környéke cönológiai vizsgálata. (The coenological investigations of Péter-hegy (mountain) and its environs in the Balaton Upland). - Veszprém Megyei Múzeumok Közleményei 12: 191-220.