Daniel Dítě

The age of island-like habitats impacts habitat specialist species richness.

While the effects of contemporaneous local environment on species richness have been repeatedly documented, much less is known about historical effects, especially over large temporal scales. Using fen sites in the Western Carpathian Mountains with known radiocarbon-dated ages spanning Late Glacial to modern times (16 975-270 cal years before 2008), we have compiled richness data from the same plots for three groups of taxa with contrasting dispersal modes: (1) vascular plants, which have macroscopic propagules possessing variable, but rather low, dispersal abilities; (2) bryophytes, which have microscopic propagules that are readily transported long distances by air; and (3) terrestrial and freshwater mollusks, which have macroscopic individuals with slow active migration rates, but which also often possess high passive dispersal abilities. Using path analysis we tested the relationships between species richness and habitat age, area, isolation, and altitude for these groups. When only matrix-derived taxa were considered, no significant positive relation was noted between species richness and habitat size or age. When only calcareous-fen specialists were considered, however, habitat age was found to significantly affect vascular plant richness and, marginally, also bryophyte richness, whereas mollusk richness was significantly affected by habitat area. These results suggest that in inland insular systems only habitat specialist (i.e., interpatch disperser and/or relict species) richness is influenced by habitat age and/or area, with habitat age becoming more important as species dispersal ability decreases.

Formal definitions of Slovakian mire plant associations and their application in regional research

We applied the Cocktail method to a large data set of 4 117 relevés of all Slovak vegetation types with the aim to create formalised definitions of all Slovakian mire plant associations. We defined 21 groups of species with the statistical tendency of joint occurrences in vegetation. These groups differed substantially in their position along the pH/calcium gradient. We further defined 24 plant associations according to presence and/or absence of certain groups and/or strong dominance of some species. Only six traditional plant associations were not possible to be reproduced this way. We applied our formalised definitions to the regional data set of mires from the surrounding of the Vysoké Tatry Mts. Combined with frequency-positive fidelity index this method has led to the classification of the majority of vegetation plots into ten associations. When the vegetation types obtained from Cocktail-based classification and from cluster analysis were compared with respect to measured pH and conductivity in the study region, 82% of pairs differed significantly either in pH or in water conductivity in the former classification and 69% in the latter one.

Distribution and Communities of Crypsis Aculeata and Heleochloa Schoenoides in Slovakia

Distribution and Communities of Crypsis Aculeata and Heleochloa Schoenoides in Slovakia The distribution and communities of two annual grasses Crypsis aculeata and Heleochloa schoenoides were studied in Slovakia during 2003-2007. Herbarium and field data were used to reconstruct the occurrence of both taxa. A strong decline in C. aculeata localities was observed. This was mainly due to the destruction of periodically flooded saline habitats. By contrast, the occurrence of H. schenoides was changed only slightly. This species survives in secondary habitats (rural roads, field margins, field depressions). Point maps of historical and recent distribution are presented. Halophile vegetation of Crypsis aculeata and Heleochloa schoenoides has been sampled with the adapted Braun-Blanquet method. All collected relevés have been classified using the JUICE software. The results showed that the Crypsidetum aculeate Wenzl 1934 community is missing now in Slovakia, but Heleochloetum schoenoidis (Soó 1933) Topa 1939 was still recorded at a few sites. However, the community contained many ruderal plant species. Raziskave razširjenosti dveh enoletnih trav Crypsis aculeata in Heleochloa schoenoides smo raziskovali na Slovaškem med letoma 2003 in 2007. Za rekonstrukcijo pojavljanja obeh vrst smo uporabili herbarrijske in terenske podatke. Opazili smo močno upadanje števila nahajališč, kjer se pojavlja C. aculeata. Razlog je predvsem uničenje periodično poplavljenih slanih rastišč. Nasprotno pa se je pojavljanje vrste H. schenoides le malo spremenilo. Vrsta lahko uspeva tudi na sekundarnih rastiščih (kolovozi, robovi njiv, uleknine na njivah). Historično in recentno razširjenost smo prikazali na točkovnih kartah. Halofilno vegetacijo vrst Crypsis aculeata in Heleochloa schoenoides smo vzorčili s prilagojeno Braun-Blanquetovo metodo. Vse popisno gradivo smo klasificirali s programom JUICE. Rezultati so pokazali, da asociacije Crypsidetum aculeate Wenzl 1934 na Slovaškem ne najdemo več, medtem ko je bila asociacija Heleochloetum schoenoidis (Soó 1933) Topa 1939 najdena na nekaj rastiščih, vendar se v njej pojavljajo številne ruderalne rastlinske vrste.

Red list of ferns and flowering plants of Slovakia, 5th edition (October 2014)

Abstract The last version of Red List was published already more than 10 years ago but the knowledge of the flora of Slovakia has substantially improved due to large-scale mapping projects and taxonomical research. Therefore an updated fifth edition of the Red List is presented in this paper. For evaluation, we accepted IUCN categories (ER, CR, EN, VU, NT, LC, DD, NA, NE) and criteria (A-D), which were used first time in the history of Slovak Red Lists of ferns and flowering plants. In total 1 218 taxa are listed (the complete list of taxa is given in Electronic Appendix 1), which is nearly 34 % of the total number of 3 619 native taxa and archaeophytes of the flora of Slovakia. More than 80 taxa (7 %) were not confirmed in the flora (66 Regionally Extinct, 17 Probably Regionally Extinct), 155 taxa are evaluated as Critically Endangered (13 %), 171 Endangered (14 %) and 201 taxa are regarded Vulnerable (17 %). The largest group represent 347 taxa evaluated as Near Threatened (29 %), 162 taxa are assessed as Least Concern (13 %), 91 taxa are in category Data Deficient (7 %), and 8 taxa belong to categories of Not Evaluated and Not Applicable (1 %). In this Red List, 27 taxa are included as new for the flora of Slovakia and 14 taxa were rediscovered. Short history of Slovak Red lists of rare and threatened plants is also briefly mentioned.

Revision of historical and current distribution of Pholiurus pannonicus (Host.) Trin. in Slovakia.

Revision of Historical and Current Distribution of Pholiurus Pannonicus (Host.) Trin. in Slovakia Historical and current occurrence of the obligate halophyte Pholiurus pannonicus was studied in Slovakia during the period 2003-2009. The species had been occurring in the Podunajská nížina Lowland and the Východoslovenská nížina Lowland; 30 localities were found in total. Recently the number of localities has decreased markedly and the species was confirmed only in the Podunajská nížina Lowland. We documented only seven localities during the study. Therefore, we confirmed that Pholiurus pannonicus belongs to the critically endangered plants of Slovak flora. Preučili smo pojavljanje obligatne halofitske vrste Pholiurus pannonicus v Podunajski nížini in Východoslovenski nížini v letih od 2003 do 2009. Vrsta se je pojavljala. Našli smo 30 rastišč. V zadnjem času se je število rastišč močno zmanjšalo in jih najdemo samo še v Podunajski nížini. Med raziskavo smo dokumentirali le sedem nahajališč. Vrsta Pholiurus pannonicus zato sodi med kritično ogorožene vrste flore Slovaške.

Succession of Saline Vegetation in Slovakia after a Large-Scale Disturbance

We studied the vegetation development in the Pannonian salt steppes in SW Slovakia (class Festuco-Puccinellietea) for eight years on permanent plots. The saline grassland was ploughed in 2002 to cultivate wheat and barley, and after two years it was left fallow. An open vegetation structure was typical for the initial stages, dominated by the obligate halophyte Tripolium pannonicum, accompanied by Atriplex littoralis and other annuals. Species richness significantly increased in the subsequent years. From the fifth year of the study, a significant increase of facultative halophytes (e.g. Lotus tenuis, Tetragonolobus maritimus, Agrostis stolonifera) and colonization of some expansive species (Phragmites communis, Calamagrostis epigejos) was observed and accompanied by a decrease in the cover of obligate halophytes (T. pannonicum and Puccinellia distans). Plantago maritima exhibited an opposite trend, and it was the only halophyte that was able to increase its population after the disturbance, due to vegetative propagation by rhizomes which increased the competitiveness of the species. The declining presence of salt-demanding species indicates a strong degradation of the saline vegetation, which might be linked to gradual desalinization of the soil. We conclude that population fluxes after adverse human disturbance and subsequent abandonment are very high, and succession of halophytic communities after such a strong disturbance is very fast, leading to deterioration of the habitat.

Mollusc Assemblages of Scandinavian Fens: Species Composition in Relation to Environmental Gradients and Vegetation

Little information exists about the ecological determinants of the mollusc species composition of Scandinavian fens. Therefore, we investigated water chemistry, hydrology, climate and vegetation composition of fens in southern and central Norway and in Sweden hosting mollusc assemblages. According to the results of the MDS ordination, variation in the mollusc composition was related to the hydrology of the studied sites, reflecting a transition from soligenous to topogenous fens. The second axis of the MDS reflected a complex gradient of mineral richness and climatic conditions. By analogy, cluster analysis revealed three main groups of sites, i.e. topogenous fens characterized by a frequent occurrence of Vertigo lilljeborgi, soligenous lowland fens characterized by Cochlicopa lubrica and Nesovitrea hammonis, and soligenous highland fens characterized by Columella columella. Results of the RDA closely resembled those of the MDS, suggesting that the selected explanatory variables defined mollusc assemblages well.

Effect of experimental top soil removal on vegetation of Pannonian salt steppes

Inland saline habitats of the Pannonian Lowland exhibit a specific variety of grasslands determined by a soil salinity gradient. Changes in the hydrological regime and absence of management have resulted in heavy degradation of the vegetation. The impact of topsoil removal on salt steppes was tested by a 3-year small-scale manipulated experiment in SW Slovakia (Kamenínske Slanisko Nature Reserve). Topsoil was removed in three contrasting types of vegetation with different soil salinities, i.e. in different stages of habitat degradation. Data were analysed by multi-way ANOVA and by multivariate methods. Species richness decreased and the proportion of halophytes increased significantly in the two types with the highest soil salinity; however, the total number of halophytes was not influenced by soil removal. The treatment caused inhibition of secondary succession on the plots with the highest salinity. The effect of the soil removal was only short-term in the vegetation with moderate salinity and on heavily degraded and desalinized types it even stimulated further recruitment of ruderal species. Topsoil removal has only limited potential for the restoration of Pannonian salt steppes. It should be applied only in slightly degraded vegetation, where salt accumulation is still present and target species propagules are available.

Relict occurrences of boreal brown-moss quaking rich fens in the Carpathians and adjacent territories

Quaking rich fens dominated by boreal semi-aquatic brown-mosses such as Scorpidium scorpioides and Calliergon trifarium are extremely rare in the Carpathians. These fens harbour endangered species persisting at few localities in the region. However, their phytosociological classification has not been sufficiently solved yet, because they lack Sphagnum species as well as calcicole species characteristic for the Caricion davallianae alliance. A recent pan-European synthesis on fen vegetation suggests that these fens belong to the Stygio-Caricion limosae alliance (boreal rich fen vegetation). The isolated occurrence of this alliance southward of the boreal zone and outside the Alps is rather exceptional and might represent a relict from an early post-glacial period. In this study, we compared phytosociological data for the Stygio-Caricion limosae alliance between Northern Europe and the Carpathians plus adjacent regions (the Bohemian Massif, the Dinaric Alps) using NMDS and cluster analysis. We found that the species composition of brown-moss quaking rich fens in Central and Southeastern Europe corresponds well with that in Northern Europe, confirming their assignment to Stygio-Caricion limosae. We further reconstructed the potential past distribution of the alliance in Czech Republic and Slovakia using available floristic and macrofossil data. Macrofossil data suggest that this vegetation type had been much more common in Central Europe and that today it persists only in ancient fens, showing the long-term stability of environmental conditions. The main causes of its present-day rarity are Middle-Holocene woodland phases in fens and recent water table decreases caused by anthropogenic deterioration of the water regime in the landscape.

Refugial occurrence and ecology of the land snail Vertigo lilljeborgi in fen habitats in temperate mainland Europe

Vertigo lilljeborgi (Westerlund, 1871) is one of the rarest terrestrial snail species in temperate mainland Europe, where it is traditionally considered a glacial relict. This contrasts with its occurrence in northern Europe where it is a widespread species. This species prefers constantly wet habitats that are neutral to slightly acidic and avoids highly alkaline conditions, which is an extremely rare ecology for a Eurasian mollusc. Until 2012, only five historical records of this species were known in mainland Europe to the south of its main distribution in northern Europe. Since then, 20 new sites have been discovered, mostly located in the Hercynian Mountains (Bohemian Massif in the Czech Republic and Massif Central in France). In comparison with the boreal European and Alpine populations, those from the Hercynian Mountains inhabit acidic, rather soligenous and productive fens, strongly dominated by Sphagnum. Vertigo lilljeborgi does not occur in some sites with apparently suitable habitats as indicated by species composition of the vegetation. We observed a surprising correspondence between the occurrence of V. lilljeborgi and mean July air temperature and we report its first fossil record from the last glacial period from Central Europe. Although the number of its sites has increased recently, these sites represent highly unusual and unique habitats, vulnerable to drainage and destruction from human activities. This highlights the need for conservation efforts in most of the newly discovered isolated sites.