B. Papp szerk.: Studia Botanica Hungarica 39. 2008 (Budapest, 2008)

Bauer, N., Lőkös, L.; Papp, B.: Distribution and habitats of Cardaminopsis petraea in Hungary

CONCLUSIONS Habitat analyses of the three major populations of Cardaminopsis petraea in Hungary provided results similar to those of other works (HEMP 1996, CERNY et al. 2006). Based on the occurrence data and habitat features in Hungary and in Central Europe the plant generally grows on rocky habitats. Its appearance cannot be strictly connected to any particular plant association or higher vegetation unit (cf. ELLENBERG 1996, HEMP 1996, CERNY et al. 2006). The occurrence of the plant is determined by microclimatic and geomorphological features providing its basic ecological requirements and vegetation historic characters. Hungary's mountainous regions were periglacial areas during glaciation in the Pleistocene with cold steppe and mosaic steppe and tundra vegetation (ZÓLYOMI 1952, FRENZEL et al. 1992), which certainly provided more favourable conditions for Cardaminopsis petraea and other alpine and boreal flora elements. Today Cardaminopsis petraea occurrences in the Balaton Uplands and in the Keszthely Mts can be characterised by intensive sub-Mediterranean features, in which the relict populations of any boreal and alpine species could only survive in the cool microclimatic microhabitats, as minor remnants of formerly more extended areas. Under the current climatic conditions, Cardaminopsis petraea can only thrive on cooler north-facing rocky slopes and rock walls in Hungary's mountainous areas. The small populations that survived in the Transdanubian Mts based on a higher diversity of other Central European populations (CLAUSS and MITCHELL-OLDS 2006, ANSELL et al. 2007) - represent a valuable gene pool. Because of their varied climatic and geomorphological characters, the Transdanubian Mts have been able to continuously provide suitable conditions for Cardaminopsis petraea since the end of the Pleistocene up to now. These areas - especially the dolomite areas (see ZÓLYOMI 1942) - are important réfugia also shown by the presence of other de-alpine and/ or boreal relict species with similar requirements (Primula auricula, Moehringia muscosa, Allium victorialis, Festuca ametbystina, etc., see ZÓLYOMI 1942, 1958, SOÓ 1964). SIMON (1972) (in his paper about the rocky vegetation of the Zemplén Mts) called the attention to the fact that the rocky grasslands of the Hungarian volcanic middle mountains play an important role in preserving relict species. Simon's assumption gets plenty of support also by