L. Hably szerk.: Studia Botanica Hungarica 23. 1992 (Budapest, 1992)
Dobolyi, Konstantin Z.: Vegetation studies on the rocky grasslands of Hór Valley (Bükk Mountains, Hungary)
STUDIA BOTANICA HUNGARICA (Àntea: Fragmenta Botanica) XXIII. 1992 pp. 69-79 Vegetation studies on the rocky grasslands of Hór Valley (Bükk Mountains, Hungary) By Z. K. DOBOLYI (Received December 15,1991) Abstract: Limestone rocky grasslands at three sites have been investigated cenologically on the basis of 50 cenological samples. Four sample groups obtained by cluster analysis have been analysed statistically according to floral element, life form, cenological character, ecological parameters and nature conservation ranks. The investigated communities belong to the Seslerio-Festucion pallentis Klika association group, have a great value from the viewpoint of nature conservation, but signs of degradation appear in their composition. With 4 tables and 4 figures. INTRODUCTION Hór Valley lies in the southern part of the Bükk Mountains and it descends in a north to south direction. It is bordered by 300-600 m high hills, parent material of which are Triassic limestone and clay slate. Rocky slopes occur frequently on the limestone hills especially on steep slopes which are covered not by forest but by grassland vegetation. The aim of this investigation was to study the structure of rocky grasslands on three representative sites of the Hór Valley: Odor-vár, Füzérkő and surrounding areas of the Subalyuk cave. The investigated sites belong to the Bükk National Park and have great importance from the viewpoint of nature conservation. METHOD Sampling was carried out so that the visibly differentiable types of grassland vegetation were represented. Fifty sample plots have been taken from a 2 x 2 m quadrate according to the BRAUN-BLANQUET method (1964). Cover is expressed in values transformed by van der MAAREL (1979) on a scale 1 to 9. The samples have been classified by an agglomerative method based on Czekanowski's similarity function and the average reduction strategy with help of the SYN-TAX III package (PODANI 1988).
