Richard Hrivnák

CONTEXT-DEPENDENCE OF DIAGNOSTIC SPECIES: A CASE STUDY OF THE CENTRAL EUROPEAN SPRUCE FORESTS

In the phytosociological literature, there are numerous different approaches to the designation of diagnostic species. Frequently, this results in discrepancies between the lists of diagnostic species published for one and the same community. We examined different approaches to determining diagnostic species using as an examplePicea abies forests within the broader context of all Central European forests. Diagnostic species of spruce forests were determined from a data set of 20,164 phytosociological relevés of forests from the Eastern Alps, Western Carpathians, and the Bohemian Massif, which included 3,569 relevés of spruce forests. Phi coefficient of association was used to measure species fidelity, and species with the highest fidelities were considered as diagnostic. Diagnostic species were determined in four ways, including (A) comparison of spruce forests among the three mountain ranges, (B) comparison between spruce forests and other forests, performed separately in each of the mountain ranges, (C) simultaneous comparison of spruce forests of each of the mountain ranges with spruce forests of the other two ranges and with the other forests of all ranges, (D) comparison of spruce forests with the other forests, using pooled data sets from the three mountain ranges. The sets of diagnostic species of spruce forests yielded in comparisons A and B were sharply different; the set resulting from comparison C was intermediate between the first two and comparison D resulted in similar diagnostic species as comparison B. In comparison A, spruce forests of the Eastern Alps had a number of diagnostic species, while the spruce forests of the other two mountain ranges had only few diagnostic species. In comparison B, by contrast, the number and quality of diagnostic species decreased from the Bohemian Massif to the Eastern Alps. This exercise points out that lists of diagnostic species published in phytosociological literature are dependent on the context, i.e. the underlying data sets and comparisons: some of these lists are useful for identification of vegetation units at a local scale, some others for distinguishing units within a narrowly delimited community type over a large area. The thoughtless application of published lists of diagnostic species outside of the context for which they were intended should therefore be avoided.

Diversity of aquatic macrophytes in relation to environmental factors in the Slatina river (Slovakia)

Distribution and plant mass of aquatic macrophytes, and their relation to environmental conditions was studied in the submontane-colline Slatina river in 2004. Diversity of macrophytes was low, only 8 vascular plants, 3 mosses and group Algae filamentosae were found. Myriophyllum spicatum is dominant species, Fontinalis antipyretica, Rhynchostegium riparioides and Algae filamentosae are frequent. Interactions between flow class, bed material, depth of water and the first three mentioned macrophytes, as well as Jungermannia leiantha were detected. Sparganium erectum prefers more antrophogenic conditions and Myriophyllum spicatum prefers the light. According to cluster analysis, three distinct and ecologically well separated parts of the river were identified. Based on Reference index, poor ecological status for the studied part of the Slatina river was estimated.

Effect of environmental variables on the aquatic macrophyte composition pattern in streams: a case study from Slovakia

The relationships between macrophyte assemblage composition and environmental variables were assessed across 39 Slovak streams in the Pannonicum and Carpathicum bioregions. Twenty-one environmental variables including geographical characteristics, hydrology, physical habitat, water chemistry, and anthropogenic stressors were assessed. A total of 89 macrophyte taxa were identifi ed, of which 26 % and 74 % were bryophytes and vascular plants, respectively. Signifi cant differences were observed between the Pannonicum and the Car- pathicum bioregions for all studied environmental variables except the following: stream width, the presence of human-made sediment and the phosphate content. Similarly, the number of species as well as the Mean Mass Total of all plant groups was signifi cantly different between the Pannonicum and the Carpathicum regions except for fi lamentous algae. Macrophyte composition in Slovak streams was affected by sediment type (5.8 %), followed by shading of shrubs and trees on the banks (3.5 %), water depth (3.0 %), NO2 - (2.8 %) and water acidity (2.2 %). Bryophytes (such as Brachythecium rivulare, Cratoneuron fi licinum, Hygrohypnum ochraceum, Lophocolea he- terophylla, Marchantia polymorpha or Rhynchostegium riparioides) and only some vascular plants (such as Persi- caria hydropiper and Glyceria notata) occur on coarser sediment types. In contrast, most vascular plants grew on fi ner sediment types.

Classification of inland Bolboschoenus-dominated vegetation in Central Europe.

Central European inland vegetation dominated by Bolboschoenus species was newly classified, based on current knowledge of taxonomic differentiation within the Bolboschoenus maritimus-complex. Altogether 225 phytosociological releves from the Czech Republic, Slovakia, Poland, Germany and Austria were analysed. Bolboschoenus-dominated vegetation is found in a broad range of both freshwater and saline habitats. Individual Bolboschoenus species grow in different habitats with different species composition. The freshwater vegetation, dominated by B. yagara, B. laticarpus and B. planiculmis, reflects ecological differentiation of these species from base-poor to alkaline substrates, and from littoral habitats to temporarily flooded depressions. The following freshwater associations were distinguished: Phalarido arundinaceae-Bolboschoenetum laticarpi Passarge 1999 corr. Krumbiegel 2006, concentrated in large river floodplains, Bolboschoenetum yagarae Eggler 1933 corr. Hroudova et al. 2009, typical of the littoral zone of fishponds on base-poor bedrocks, and Tripleurospermo inodori-Bolboschoenetum planiculmis Hroudova et al. 2009, occurring mainly in temporarily flooded depressions on arable land. Saline vegetation is dominated by Bolboschoenus maritimus s. str. The alliance Cirsio brachycephali-Bolboschoenion compacti (Passarge 1978) Mucina in Balatova-Tulackova et al. 1993, previously interpreted as vegetation of inland saline marshes, actually relates to freshwater Bolboschoenus vegetation. Therefore a new alliance, Meliloto dentati-Bolboschoenion maritimi Hroudova et al. 2009, is proposed here to include saline reed vegetation of continental areas.

Seasonal dynamics of macrophyte abundance in two regulated streams

This study analysed seasonal dynamics of macrophyte abundance in two perennial lowland regulated streams (Stream 1 and 2) in the Danube basin (Slovakia). Assessments of macrophyte abundance and environmental characteristics were accomplished 7 times during the vegetation period in 2005 within a 100 m long section. Statistically significant differences in total abundance of macrophytes as well as an abundance of macrophyte groups (hydrophytes, amphiphytes, helophytes) and Potamogeton nodosus were detected among months within the vegetation period. Abundance fluctuations for individual macrophyte groups and species were moderate in Stream 1 and much stronger in Stream 2. Only amphiphytes showed bimodal temporal distribution in Stream 1, but the abundance of this group was low, reflecting more or less random occurrence of species in vegetation period. Multiple linear regression revealed that water depths and air temperature are the most significant environmental variables affecting the seasonal pattern of total as well as dominating group abundance in Stream 1 and 2, respectively. In all cases, abundances are significantly influenced by the abundance of the respective group in the preceding month. Culmination time differed between streams for all macrophyte groups except helophytes. Total abundance culminated 0.57 month later in the Stream 1 compared to Stream 2.

Mire vegetation of the Muránska Planina Mts — formalised classification, ecology, main environmental gradient and influence of geographical position

Mire vegetation of the Muránska planina Mts and adjacent parts of neighbouring orographical units was studied in 1998–2005 using the standard Zürich-Montpellier (Braun-Blanquet) approach. We applied the defined phytosociological species groups and national formal definitions of mire associations in data processing. Within the classes Scheuchzerio-Caricetea fuscae and Oxycocco-Sphagnetea, seven associations (Caricetum davallianae, Carici flavae-Cratoneuretum filicini, Valeriano simplicifoliae-Caricetum flavae, Caricetum goodenowii, Carici echinatae-Sphagnetum, Carici rostratae-Sphagnetum and Pino mugo-Sphagnetum) were classified using formal classification criteria. Two other communities (Sphagno warnstorfii-Caricetum davallianae and Eriophoro vaginati-Sphagnetum recurvi) were not classified due to the lack of sufficient number of diagnostic species from species groups. The first DCA axis followed the mineral richness gradient. Vegetation plots were arranged from rich fens over moderately rich fens towards poor Sphagnum fens and raised bog. This fact was confirmed by a strong and significant correlation of the DCA site scores on the first axis with the measured pH and water conductivity as a surrogate of mineral richness. The second DCA axis correlated with mean Ellenberg’s indicator values for both temperature and soil nutrients. This pattern corresponds to that found in other regions of diversified Central-European landscape. We can therefore conclude that marginal geographical position and climatic specifity of the region under study did not alter gradient structure of the mire vegetation. When diversity of mire vegetation was compared to other regions in Slovakia by applying the same formal definitions to different regions, the study region was found to be conspicuously less diverse than the distribution centres of mire habitats in Slovakia (Orava and Vysoké Tatry regions), but more diverse than most of other marginal regions of mire distribution. Relatively high beta diversity of mires was probably caused by variable bedrock and local climate.

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.

Numerical classification of alder carr and riparian alder forests in Slovakia

Syntaxonomy and ecology of the alder carr (alliance Alnion glutinosae) and riparian alder forests (suballiance Alnenion glutinoso-incanae) of Slovakia have not yet been critically revised. Application of numerical approach allowed us to disentangle and resolve syntaxonomical affinities among vegetation units previously reported in Slovakia. The present synthesis was based on analysis of 918 recent and historical phytosociological relevés originating from the Slovak Vegetation Database and available unpublished sources. Three floristically and ecologically interpretable associations of the Euro-Siberian alder carr forests of Alnion glutinosae (Thelypterido palustris-Alnetum glutinosae Klika 1940, Carici elongatae-Alnetum glutinosae Tüxen 1931, Carici acutiformis-Alnetum glutinosae Scamoni 1935) and seven of the European ash-alder riparian forests of Alnenion glutinoso-incanae (Carici remotae-Fraxinetum excelsioris Koch ex Faber 1936, Stellario nemorum-Alnetum glutinoase Lohmeyer 1957, Pruno padiFraxinetum excelsioris Oberdorfer 1953, Matteuccio struthiopteridis-Alnetum glutinosae Magic et Kliment in Kliment et Watzka 2000, Cardamino amarae-Alnetum incanae Šomšák 1961, Piceo abietis-Alnetum glutinosae Mráz 1959, Alnetum incanae Lüdi 1921) have been identified using unsupervised numerical classification. Each association was characterized by list of synonyms, diagnostic, constant and dominant species, overall floristic description, site requirements and chorological aspect. Main environmental gradients responsible for vegetation changes were determined in detrended correspondence analysis and interpreted using the Ellenberg indicator values (EIV) and altitude. Variation in species composition pattern corresponded to the altitudinal gradient and EIV for moisture, nutrients and soil reaction.

Environmental thresholds and predictors of macrophyte species richness in aquatic habitats in central Europe

The degradation of habitats and species loss in freshwaters is far greater than in any other ecosystem. The decline in biodiversity has a strong potential to alter the functioning of the ecosystem and the services they provide to human society. Therefore, there is an urgent need for accurate information on patterns and drivers of diversity that could be used in the management of freshwater ecosystems. We present the results of an analysis of the relationships between macrophyte species richness and environmental characteristics using an extensive dataset collected from 160 sites in two central-European bioregions. We modelled macrophyte species richness using recursive partitioning methods to assess the diversity-environmental relationships and to estimate the environmental thresholds of species richness in rivers, streams, ditches and ponds. Several hydrological and chemical variables were identified as significant predictors of macrophyte richness. Among them, pH, conductivity, turbidity and substrate composition appeared as the most important. There is also evidence that natural ponds support a greater number of plant species than man-made ponds. Based on the detected environmental thresholds, we offer a series of simple rules for maintaining higher macrophyte species richness, which is potentially useful in the conservation and management of aquatic habitats in central Europe.

Vegetation of the aquatic and marshland habitats in the Orava region, including the first records of Potametum alpini, Potametum zizii and Ranunculo-Juncetum bulbosi in the territory of Slovakia

The vegetation of the aquatic and marshland habitats of the Orava region (north of Slovakia) was studied in 2009, using traditional phytosociological methods. Sixteen aquatic and eighteen marsh plant communities were described within 96 phytosociological relevés by using TWINSPAN with the application of the dominance principle. Three associations, Potametum alpini, Potametum zizii and Ranunculo-Juncetum bulbosi, were found as new communities for Slovakia. Myriophylletum verticillati, Potametum nodosi, Potametum graminei and Alisma gramineum community were recorded in the northernmost localities in Slovakia. Among marsh communities, Calletum palustris is very rare, both in the Orava region and in Slovakia as a whole. According to Ellenberg’s indicator values (EIV), moisture was evaluated as the main ecological gradient. Plant communities are ordered along the first Detrended Correspodence Analysis (DCA) axis in a typical hydroseries (Potametea → Lemnetea → Phragmition communis → Phalaridion arundinaceae, Oenanthion aquaticae and Sparganio-Glycerion → Magnocaricion elatae). The second DCA axis was most correlated with EIV for nutrients. Among the five directly measured ecological characteristics (temperature, pH and conductivity of water, water depth, and substrate type), conductivity of water (0.44, P < 0.01) and substrate type (0.32, P < 0.05) were the statistically significant variables explaining the variability along the first DCA axis.