A Veszprém Megyei Múzeumok Közleményei 7. (Veszprém, 1968)

Papp Jenő: A Bakony-hegység állatföldrajzi viszonyai

A Zoogeographical Outline of the Bakony-Mountain Introduction. — In the last decade, within the frame of the investigation programme „Nature-landscape of the Bakony", zoologioal investigation in the Bakony has taken an upswing. In the Hungarian zoological literature between 1940 and 1960 publications on the fauna of the Bakony were getting more and more frequent. With the time approaching to our days publications of data and essays having the Bakony for their exclusive topic are on the rise. Facts that indicate the revival of zoological investigation in the Bakony. Geographical description of the Bakony. — The Bakony is a well-confined central mountain range of the Carpathian Basin, lying in the middle part of Transdanubia north of the Lake Balaton (Fig. 1). Geomorphologically it is divided into six subdistricts with a total extension of 4000 km-. The Bakony is a worn-off mountain, whose surface is formed of 200—700 m high mountains and hills alternating with plateaus and basins. Besides its highest peak, Kőris-hegy (704 m), it has five peaks rising above 600 m. The present block of the mountain arose from the Varisoan base at the bottom of the Hungarian system of basins through faults and scalations at the time of late tertiary alp-formations. Characteristic of its structure are four longitudinal (NE—SW) and more transversal (NW—

SE) faultlines which may happen to be boundaries of certain subdistricts. Along the fault-lines the surface crust is showing faultage and scalation, it is shifted together or pushed apart. The bulk of the Bakony, consists of sedimentary tertiary limestone and dolomite (average thickness 2000 m). Its further components in the order of importance are: basalt, fresh-water limestone, gravel, clay, sand and loess ÍLÁNG 1958, 1962). Climate of the Bakony. — In the northern half of the Bakony has Hungary her largest coherent humid area. On the other hand, the southern half of the Bakony (Balaton-felvidék = Balaton-Highland) is one of Hungary's regions with the mildest climate. Due partly to the Balaton partly to the geomorphological features of the highland the region has a mediterranen character of mesociimatic feavour. In general the Bakony's climate (similarly to the climate of more other members of the Hungarian Central Mountain Range) (KAKAS 1960, 1963; RÉTHLY 1940) lies within the area of concurrence of the Atlantic, continental and mediterranean climate-effects. — The annual precipitation of the Mountain is 600—800 m (the national average is 300—500 mm), from March to late October (period of vegetation) 500—650 mm, with a fairly even yearly distribution. The yearly average temperature is 9 —9,5 C° (the national average is 8—11 C

c

). The temperature, depending on the altitude above the sea-level, fluctuates between 8,5 and 10,5 C° (NorthBakony: 8,5—9 C°, Balaton-Highland 10,5 C°), during the period of vegetation it is 14—15 C°, in the summer months 18—21 C°. The number of sunny hours in the year is 1400—1450 (the national average is 1450—1500). The prevailing wind-direction is NW. — In spite of the 600—800 mm precipitation there is a scarcity of rivers and still water since the limestone and dolomite let the water pass through into underlying cavities. For this reason, especially at the time of precipitation-minimum in late summer the vegetation suffers from water-shortage in many places, a fact that makes itself felt by the fauna, too. Gerence, Cuha, Gaja, Séd, Eger and Lesence are steady brooks, abounding in water. Vegetation of the Bakony. — The Bakony-Mountain is the western -member of the Transdanubian half (phytogeographical Bakonyicum) of the Hungarian Central Mountain Range (FEKETE 1964). The mountain that is considered to be one geomorphological unit is divided between two floristic districts (Vesprimiense and Balatonicum) which extend also to the Vertes-Mountain. Characteristic of its flora and vegetation — according to its climatic conditions — are the sub-Atlantic, Central European, Illyrian, and mediterranean species of balanced climatic demands and their plani communites. In suitable micro- and mesociimatic ambients also alpine and subalpine elements occur. Remarkable plant species of the Bakony are the following: Primula auricula, Allium victorialis, Trollius europaeus (subalpine elements) — Taxus baccata, Primula acaulis, Ruscus aculeatus (Atlanto-mediterranean elements) — Daphne cneorum, Eranthis hiemalis, Cotinus Coggyria, Scilla autumnalis, Hemerocallis lilioasphodelus, Asphodelus albus, Crocus Heuffelianus, Stipa bromoides (mediterranean elements). Beside the prevailing calciphilous plant communities acidophil vegetation types of smaller extension occur in the western parts. In the original floristic picture the oaks ore prevailing but due to sub-Atlantic climateeffects also beech-woods can occur. In the basins and on the gentle slopes people till the arable land, grow fruits and wine. The climax-vegetation of the Bakony consists in the various oak- and beechwoods. On the average the oak-woods appear up to 300—350 m above the sea-level. From 300 to 700 m stretches the zone of beech-woods. The oak-woods of the Bakony in the order of occurrence frequency are as follows: Orno-Quercetum, Cotino-Quercetum. Fago-Ornetum (mainly on southern and south-westerly slopes and ridges) — Quercetum petraeae-cerris, Potentillo-Quercetum asphodeletosum, QuerceioCarpinetum and Buzulo-Quercetum (on nutritive woodland grounds). These oak-woods serve as habitats to a great deal of animal species characteristic of central mountain ranges and often they house faunal curiosities. The beeches of the Bakony (Melico- or Melitti-Fagetum) form beautiful forests, especially in the North-Bakony. The usual habitat of the Bakony's alpine species is the zone of the beech-woods which, apart from the North-Bakony, are low in number. A possible reason for this is that the beech-woods themselves are of sub-alpine character. The open plant communities are mostly spread over widening valleys, lowlands, mountain310