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Richard Hrivnák

Macrophyte Vegetation of Artificial water Reservoirs in the Krupinská Planina Mts., Including the First Record of Potametum Acutifolii from Slovakia

Research of macrophyte vegetation of the artificial water reservoirs was carried out during the vegetation season of 2008 in the Krupinská planina Mts. (southern part of central Slovakia). Twenty-one reservoirs were studied and twenty plant communities from the Lemnetea, Potametea and Phragmito-Magnocaricetea classes were found. Potametum acutifolii is a new aquatic community for the territory of Slovakia that was found in the reservoir near Hrušov village in intermediately deep, slightly alkaline water with a relatively low content of soluble mineral matters, a high water transparency and a silt-clay sediment on the bottom. Moisture was the main environmental gradient of the studied vegetation explained by Ellenberg's indicator values. Species richness was significantly negatively correlated with water depth. The correlation between the area of reservoirs and the number of detected plant communities was weak and non-significant. Changes of macrophyte vegetation were studied on the case of three reservoirs. Detected changes were caused mainly by human activities or water level fluctuations within the studied period.

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Michal Slezák, Richard Hrivnák and Anna Petrášová

Syntaxonomy and Ecology of Black Alder Vegetation in the Southern Part of Central Slovakia

The study presents phytosociological and ecological data from azonal black alder forest sites in the southern part of central Slovakia. A data set of 29 relevés was collected by authors in vegetation season 2010 following the standard Braun-Blanquet approach. Numerical classification was performed to delimit the main vegetation types, while statistical analyses were applied to explain the vegetation-environmental relationships. Three associations within two classes were distinguished using a TWINSPAN algorithm. Carici elongatae-Alnetum glutinosae Schwickerath 1933 is an alder carr forest occurring on waterlogged soils in spring fed areas and alluvial zones along rivers. Carici acutiformis-Alnetum glutinosae Scamoni 1933 represents an alder carr forest on habitats with stagnant or slowly flowing water along water courses and artificial water reservoirs. Mesic to humid stands along small brooks are typical for the riparian alder vegetation of Stellario-Alnetum glutinosae Lohmeyer 1957. A detailed description of the floristic and ecological features of these associations is presented. The major environmental gradients affecting variation in species composition of these communities were interpreted as a response of vegetation to soil moisture and nutrient availability regarding the Ellenberg indicator values (moisture and nutrients) and measured variables (total N and C).

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Daniel Dítě, Pavol Eliáš, Richard Hrivnák and Zuzana Melečková

Beckmannia Eruciformis (L.) Host in Slovakia - Distribution, Ecology and Coenotic Affinity: Dedicated to the memory of Ján Bogoly (1951 - 2011)

The historical and recent distribution, ecology and phytosociology of perennial grass Beckmannia eruciformis was studied in Slovakia between 2002 and 2010. Altogether 22 natural and two secondary sites with presence of the species were found from published sources, herbaria and field research. Localities of its native occurrence have been concentrated in Eastern Slovakia (Východoslovenská nížina Lowland from the settlement of Streda nad Bodrogom to the villages of Pribeník and Biel). Secondary sites were found in Western Slovakia (Podunajská nížina Lowland; the surroundings of Sládkovičovo town and Jaslovské Bohunice village). The relatively massive reduction of Beckmannia eruciformis localities was recorded in the seventies and eighties of the last century; it was related to massive land reclamation and alterations in the water regime of river alluvia. Recently only seven localities were found. Permanent occurrence was confirmed only in two localities (Malý Horeš, Strážne). In those cases Beckmannia eruciformis has created relatively large populations including some thousands of individuals. All other recent occurrences were temporary (Streda nad Bodrogom, Keresztúr farmstead, Horešské lúky Nature Reserve, Veľký Horeš, Pribeník). Moreover, they were relatively poor in the number in individuals and are acutely threatened by anthropogenic changes of environmental conditions. According to our results and by applying the IUCN criteria, we propose to modify the threat category of the species from critically endangered (CR) to endangered (EN) in Slovakia. Occurrence of the association Beckmannietum eruciformis and the alliance Beckmannion eruciformis, was also not confirmed for Slovakia during our research. We believe that the association was not present in the past either. Recently, Beckmannia eruciformis was found in the stands of Oenanthion aquaticae (Phragmito-Magnocaricetea) and Potentillion anserinae (Molinio-Arrhenatheretea) in two localities (Malý Horeš, Strážne) during our study. The species composition of the mentioned alliances is fundamentally influenced by the ecological conditions of sites, mainly by water regime during the vegetation period. According to our knowledge, the most favourable conditions for Beckmannia eruciformis are the following: short-term and low floods in the spring, decrease of the water table at the beginning of summer and relatively high level of groundwater during next part of vegetation period. On the contrary, the species may not appear on the site in case of unfavourable weather conditions (dry years).

Open access

Daniel Dítě, Richard Hrivnák and Pavol Eliáš Jun

Abstract

Utricularia bremii Heer, considered extinct in Slovakia for about 60 years, has been rediscovered in shallow fen pools at Hanšpilje (Plavecký Peter village, SW Slovakia) in 2006. The water of the fen pools is of moderate conductivity (272 μS cm-1) and pH 7.0. As a result of peat extraction in the past, the site is covered by depauperated vegetation with fen species characteristic of the alliance Caricion davallianae and wetland species characteristic of the class Phragmito-Magno-Caricetea. Stands with U. bremii were classified as the association Campylio stellati-Caricetum lasiocarpae (class Scheuchzerio-Caricetea fuscae). Brief information on the vegetation history of the Hanšpilje site, its ecology, and the vegetation preferences of U. bremii are presented in the European context. Based on our results, we propose to change the status of U. bremii on the Slovak red list from ‘extinct’ to ‘critically endangered’.

Open access

Richard Hrivnák, Jaroslav Košťál, Michal Slezák, Anna Petrášová and Melánia Feszterová

Abstract

In some regions of Slovakia, black alder forest vegetation has not been documented appropriately yet. This paper is the first vegetation study presenting the phytosociological data and measured environmental parameters from the western part of central Slovakia. The data set was classified by using a modified TWINSPAN algorithm, which allowed us to discern floristically and ecologically distinctive plant communities. They correspond to the associations Stellario nemorum-Alnetum glutinosae Lohmeyer 1957 (riparian alder vegetation on mesic to humid sites along small brooks) and Carici acutiformis-Alnetum glutinosae Scamoni 1935 (eutrophic black alder carr forests in the colline zone) with the variants of Ligustrum vulgare and Galium palustre. The community Carici elongatae-Alnetum glutinosae Schwickerath 1933 (mesotrophic to eutrophic alder carr vegetation growing on permanently waterlogged soils), documented only with two phytosociological relevés, was distinguished following expert knowledge. A floristic and ecological pattern of these associations is presented.

The major compositional gradients were interpreted based on Ellenberg’s indicator values and the values of environmental variables recorded during the field sampling in the growing season 2011. The principal component analysis revealed the importance of soil moisture, light availability, portion of open water and soil surface for species composition variability at the association level, whereas the variants of Carici acutiformis-Alnetum glutinosae were sorted along the acidity gradient.

Open access

Jana Májeková, Dominik Roman Letz, Michal Slezák, Marica Zaliberová and Richard Hrivnák

Abstract

The paper presents data on the occurrence and secondary spreading of rare and threatened vascular plant species in railway habitats of Slovakia. We recorded 17 threatened vascular plant species and other 9 species that we considered to be rare in Slovakia. They grew at railway stations, mainly directly in the rail yard and also at the platforms or other similar facilities. Records of further 39 species were excerpted from literature sources. More native thermophilous species were represented among the recorded species as railway substrates provide suitable conditions for their growth. Also some archaeophytic segetal species were found quite frequent in the studied biotopes due to spreading of their seeds together with cereals transported by trains. Various habitats of railway transport facilities often provide suitable conditions for the secondary occurrence and further spreading not only of synanthropic or adventive, but also of rare and threatened plant species.