Matskási István (szerk.): A Magyar Természettudományi Múzeum évkönyve 88. (Budapest 1996)
Csontos, P., Horánszky, A. , Kalapos, T. ; Lőkös, L.: Seed bank of Pinus nigra plantations in dolomite rock grassland habitats, and its implications for restoring grassland vegetation
ANNALES HISTORICO-NATURALES MUSEI NATIONALIS HUNGARICI Volume 88. Budapest, 1996 pp. 69-77. Seed bank of Pinus nigra plantations in dolomite rock grassland habitats, and its implications for restoring grassland vegetation P. CSONTOS 1 , A. HORÁNSZKY 1 . T. KALAPOS 1 & L. LŐKÖS 2 ^Department of Plant Taxonomy and Ecology, Eötvös Loránd University (ELTE) H-1083 Budapest, Ludovika téri, Hungary 9 Department of Botany, Hungarian Natural History Museum H-1087 Budapest, Könyves Kálmán krt, 40, Hungary CSONTOS, P., HORÁNSZKY, A., KALAPOS, T. & LŐKÖS, L. (1996): Seed bank of Pinus nigra plantations in dolomite rock grassland habitats, and its implications for restoring grassland vegetation. Annls hist.-nat. Mus. nain. hung. 88: 69-77. Abstract - Dolomite grasslands of the Hungarian Central Range represent high botanical value, preserving several relic and endemic species and associations. These areas were extensively afforested with the alien black pine (Pinus nigra ARN.) during this century. Recently, restoration of the dolomite grassland vegetation started in nature reserves. Therefore, the soil seed bank of the black pine plantations was studied to evaluate its possible role in grassland restoration. Germination tests indicated an impoverishment of the seed bank of the former grassland vegetation under the studied 55-year-old forests. This trend increased with higher density of tree-canopy (92.4 seeds/sqm at 65% - and 39.6 seeds/sqm at 80% canopy cover. Six dolomite grassland components maintained a long-term persistent seed bank: Campanula sibirica, Colutea arborescens, Filipendula vulgaris, Polygala amara, Teucrium montanum and Viola rupestris. The relatively high ratio of wind dispersed seeds of weeds or species from other natural communities implies that the removal of black pine over large areas would lead to the dominance of these species. In order to promote the immigration and establishment of the dolomite rock grassland species, a successive cutting system is proposed. With 2 tables. INTRODUCTION Grasslands developed on shallow, rocky soils of dolomite hills form one of the characteristic landscapes in the Hungarian Central Range. The intense physical weathering of exposed dolomite bedrock and the associated downward movement of rock debris along steep slopes slow down soil formation processes and prevent the establishment of forest vegetation. It also produces a wide variety of microhabitats with contrasting microclimate. As a consequence, the natural grassland vegetation is rich in species and contains several relic and endemic elements. It is hypothesized that these grasslands served as réfugia for lowland steppe species during the Pleistocene glaciation periods. The characteristic vegetation of this landscape was recognized as early as the turn of the last century (BORBÁS 1900), and later the theories of its existence and role in the vegetation history of the Carpathian Basin were developed (ZÓLYOMI 1942, 1952).
