Volumen 11 (2012): Edición 2 (December 2012)

Historical and current occurrence of halophytic-ruderal species Hordeum geniculatum was studied in Slovakia during 2003 - 2010. The species occurred only in the Podunajská nížina Lowland, where 16 sites were found in total including historical and recent locations. Recently, the number of sites decreased markedly and we confirmed only four localities. Due to the sharp decrease in the number of sites and proper habitats, Hordeumgeniculatum is re-evaluated as endangered (EN) plant of Slovak flora.

In the present study, we investigated plant communities with Yellow Oat Grass (Trisetum flavescens (L.) Pb.) in the submontane and montane regions of Slovenia. In 2005-2007 ninety-one relevés were collected by using the standard procedure of the Braun-Blanquet approach. Relevés were analysed with multivariate analysis and classified within two associations: Astrantio-Trisetetum (Polygono-Trisetion) and the Pastinaco-Arrhenatheretum (Arrhenatherion). Management practices, soil conditions and altitude were found to be significant factors for a further subdivision of both associations. Within the Astrantio-Trisetetum association three subassociations could be distinguished: -typicum, -buphthalmetosum and -trollietosum, and subassociations -typicum, -medicagetosumlupulinae, as well as -lolietosum subass. nova in the Pastinaco-Arrhenatheretum. The floristic composition and ecological characteristics of these plant communities are described and their implications for grassland conservation in Slovenia are discussed.

Changes of species composition, plant community strategy and functional response trait turnover were studied in a succession from dry pastures to a forest community (oak-hornbeam forests). The following question was asked: are functional response traits and plant community strategies indicators of TAA (time since agricultural land use abandonment), thus of a specific succession stage.

Indirect gradient analysis (DCA) was used in order to observe the position of the relevés along the axis and to correlate it with TAA. It was found that the position of relevés on DCA axis 1 is our proxy for TAA. Correlations (Spearman’s rho) between the occurrence of plant functional traits and TAA were performed.

Low-growing herb species with scleromorphic leaves and green or red flowers are the predominant plant type on grassland areas, while plant species with digitate, hydro or mesomorphic leaves and white flowers typically prevail in forest. The proportion of chamaephytes increases immediately after land abandonment (afforestation). In a closed forest stand, there are many more herb species with vegetative propagation (bulbils). Herbal species in those stands most often reward pollinators with pollen. The ecological strategy of the entire plant community changes with spontaneous afforestation. On grassland, stress-tolerant species are dominant. After 10 years, the community is defined as CS and after 200 years as a community with a C-CS strategy.

A total of 546 releves collected in western Bulgaria and referred to Festuco-Brometea were classified into the alliances Festucion valesiacae, Saturejion montanae, Cirsio-Brachypodion pinnati and Chrysopogono-Danthonion calycinae. All releves assigned to alliance Cirsio-Brachypodion pinnati were further classified towards lower level which resulted in the description of a new association - Hieracio pilosellae-Festucetum dalmaticae and two new subassociations added to ass. Galio lovcense-Artemisietum chamaemelifoliae. Both associations were ecologically well differentiated on the basis of soil parameters (pH and humus content) as well as some additional factors (exposition, land use, etc.).

The paper presents results of actual phytocoenological research of acidophilous dry grasslands of the Koelerio-Phleion phleoidis Korneck 1974 alliance on the quartzite bedrock in western Slovakia. The modified TWINSPAN analysis distinguished two associations in the study area. Avenulo pratensis-Festucetum valesiacae Vicherek et al. in Chytry et al. 1997 is dominated by Festuca valesiaca s.l. and it is distributed on the quartzite hills in the Tribeč Mts. Potentillo heptaphyllae-Festucetum rupicolae (Klika 1951) Toman 1970 occurs at sites in the Biele Karpaty Mts and Považsky Inovec Mts and it is dominated by Festuca rupicola. The paper brings very first data on distribution of Avenulo pratensis-Festucetum valesiacae in Slovakia and extends knowledge on occurrence of Potentillo heptaphyllae-Festucetum rupicolae. Both associations represent very rare vegetation types of Central Europe. In Slovakia, they occur locally at small sized stands and are threatened by successional changes caused by cessation of traditional management and island occurrence within other vegetation types. Main environmental gradients responsible for variation in species composition of these grasslands were revealed by the principal component analysis (PCA) and interpreted using indicator values and measured characteristics of the study sites. The major pattern of variation reflects altitude, which is negatively correlated with temperature and soil depth. The relationship between species composition and environmental factors (pedology, topography, geographical position) was analysed by redundancy analysis (RDA). The most important factor affecting the data variation was longitude followed by soil pH, slope and latitude.

The evolutionary history of Ophioglossaceae is enigmatic mainly because fossils of the family trace back only from the earliest Tertiary. Phylogenetic analyses indicate that Helminthostachys is sister to the broadly defined Botrychium. Generally the sporophore of Botrychium is a pinnately compound, whereas it is simple in Helminthostachys. Here examples of different Helminthoistachys are represented which show double or triple spikes with some variations. Plants showing variations in their spike morphology are also grown normally. Variations of Helminthostachys spike morphology indicate a tendency to form a compound sporophore structure and in that way have a strong relationship with Botrychium.