L. Hably szerk.: Studia Botanica Hungarica 18. 1985 (Budapest, 1985)

Dobolyi, Z. Konstantin; Szerdahelyi, Tibor: Vegetation studies on the rocky grassland of the "Várhegy" at Sümeg

STUDIA BOTANICA HUNGARICA (Antea: Fragmenta Botanica) XVIII. 1985 p. 87-95 Vegetation studies on the rocky grassland of the "Várhegy" at Sümeg By 2. K. DOBOLYI and T. SZERDAHELYI (Received November 30, 1984) Abstract: Samples have been taken in an open limestone rocky grassland from the SSE and NNW part of the "Várhegy" at Sümeg. The two each of the 20 samples groups have been examined and compared with each other according to their floral elements, species composition, ecological requirements, life-forms and cenological characters. INTRODUCTION The "Várhegy" at Sümeg is the western part of the Southern Bakony Mountains. The hill is approximately symmetrically conical, its height is 270 m. The diameter of the lower part of the hill is about 400 m, the angle of the slope is on the average about 30-40°. The underlying rock of the hill is Crinoidean limestone of the Middle Cretaceous period. On the top of the hill there are ruins of a mediaeval castle that used to be of military importance. The slopes had probably been covered with Cotino-Quercetum pubescentis association and the vegetation of the bottom of the hill was Orno-Quercetum. Originally the extension of the rocky grassland was smaller than nowadays. The changes in the vegetation were mostly induced by anthropogenic effects. Now the whole area of the hill is without trees, only in the western part can small bushes be seen. Open rocky grassland most similar to the original vegetation occurs in the upper third of the hill in SSE and NNW exposure. The heavily used places (because of heavy tourism) on the other part of the hill are covered by rocky slope steppe and ruderal associations. The goal of this study was a cenological examination of two samples of opposite exposure. However, the two parts of opposite exposure were markedly different from each other in view of microclimate and species composition, so " it seemed useful to examine and analyse the vegetation of the two areas separately. MATERIAL AND METHOD The study is based on 40 cenologic samples. These samples of have been taken from a 2 x 2 m quadrat according to the Braun-Blanquet method (1964). Since our aim was to examine the relatively intact rocky grassland, we have tried to avoid marking out degraded areas (weedy, trodden place) in the samples. We have separated the samples into two groups according to their exposure. The samples taken on the SSE part from the first group, while the second group represents the samples of the NNW part. Both groups contain 20 samples. The species in the groups (soil pH, temperature, moisture and nitrogen requirements). These cenological parameters are expressed in a scale 0-5 (R, T, F, N values). Number 0 means indifference to the ecological parameter. The characteristic parameters of the species are taken from So6'

s Synopsis (1964-80). The distribution of the characters in the two sample groups are represented in percentage pro rata (one species may belong to several categories with respect to floral element and ecological requirement, so the sum of the values may exceed 100 %).