Michal Slezák

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of 918 recent and historical phytosociological relevés originating from the Slovak Vegetation Database and available unpublished sources.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.

Rare and threatened vascular plants of the railways in Slovakia

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.

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

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). V članku so predstavljeni fitosociološki in ekološki podatki iz azonalnih gozdov črne jelše v južnem delu osrednje Slovaške. V vegetacijskem obdobju leta 2010 smo naredili 29 popisov po standardni Braun-Blanquetovi metodi. Z numerično klasifikacijo smo opredelili glavne vegetacijske tipe, s statističnimi metodami pa pojasnili povezavo med vegetacijo in okoljskimi dejavniki. Z algoritmom TWINSPAN smo ločili tri asociacije znotraj dveh razredov. V asociacijo Carici elongatae-Alnetum glutinosae Schwickerath 1933 uvrščamo jelševe greze na rastiščih z visoko talno vodo ob potokih in na aluvialnih ravninah ob rekah. Asociacija Carici acutiformis-Alnetum glutinosae Scamoni 1933 predstavlja jelševe gozdove na rastiščih z zastajajočo ali počasi tekočo vodo ob vodotokih in umetnih vodnih telesih. Mezofilni do vlažni sestoji ob majhnih potokih so značilni za asociacijo Stellario-Alnetum glutinosae Lohmeyer 1957. V članku so podrobno opisane floristična sestava in rastiščne značilnosti teh asociacij. Glavni ekološki gradienti, ki se kažejo v vrstni sestavi, so talna vlaga in hranila. Med Ellenbergovimi indikatorskimi vrednostmi sta to vlažnost in hranila, med merjenimi spremenljivkami pa skupni N in C.

History and environment shape species pools and community diversity in European beech forests

A central hypothesis of ecology states that regional diversity influences local diversity through species-pool effects. Species pools are supposedly shaped by large-scale factors and then filtered into ecological communities, but understanding these processes requires the analysis of large datasets across several regions. Here, we use a framework of community assembly at a continental scale to test the relative influence of historical and environmental drivers, in combination with regional or local species pools, on community species richness and community completeness. Using 42,173 vegetation plots sampled across European beech forests, we found that large-scale factors largely accounted for species pool sizes. At the regional scale, main predictors reflected historical contingencies related to post-glacial dispersal routes, whereas at the local scale, the influence of environmental filters was predominant. Proximity to Quaternary refugia and high precipitation were the main factors supporting community species richness, especially among beech forest specialist plants. Models for community completeness indicate the influence of large-scale factors, further suggesting community saturation as a result of dispersal limitation or biotic interactions. Our results empirically demonstrate how historical factors complement environmental gradients to provide a better understanding of biodiversity patterns across multiple regions.A continent-wide analysis of community assembly in European beech forests shows different emphasis on historical or environmental effects on species pools across different scales.

Oak forest vegetation in the northern part of the Štiavnické vrchy Mts (Central Slovakia)

Oak forest vegetation in the northern part of the Štiavnické vrchy Mts (Central Slovakia) The phytosociological research of the oak forest vegetation was carried out in the northern part of the Štiavnické vrchy Mts (Central Slovakia) using the standard Zürich-Montpellier approach. The data set consisting of 41 phytosociological relevés was obtained by the authors in two vegetation seasons in 2008 and 2009. The numerical classification and the ordination methods were applied to determine the main vegetation types and to explain the structure of the vegetation-environmental data matrix, respectively. Four associations within two classes were distinguished: Luzulo albidae-Quercetum petraeae Hilitzer 1932, typical for shallow, mineral-poor and acidic soils, Melico uniflorae-Quercetum petraeae Gergely 1962 occuring on mesic stands with skeletal and deeper soils, Poo nemoralis-Quercetum dalechampii Šomšák et Háberová 1979 developing on moderately canopyopened stands in the submontane belt, Sorbo torminalis-Quercetum Svoboda ex Blažková 1962 growing on moderately acidic substrates in drier regions. The major environmental gradients responsible for variation in forest species composition was associated with soil nutrient and soil reaction following the Ellenberg indicator values as well as the measured environmental variables (C/N-ratio and soil acidity). Special attention was given to the discussion on species composition and site ecology. Fitocenološke raziskave hrastovih gozdov v severnem delu gorovja Štiavnické vrchy (srednja Slovaška) smo naredili po Zürichško-Montpellierski metodi. Enainštirideset vegetacijskih popisov smo naredili v dveh vegetacijskih sezonah v letih 2008 in 2009. Za določitev glavnih vegetacijskih tipov in za obrazložitev strukture podatkovne matrike vegetacijskih popisov in ekoloških spremenljivk smo uporabili numerično klasifikacijo in ordinacijo. Znotraj dveh razredov smo ločili štiri asociacije: Luzulo albidae-Quercetum petraeae Hilitzer 1932, značilna za plitva, z minerali revna, kisla tla, Melico uniflorae-Quercetum petraeae Gergely 1962, ki se pojavlja na mezičnih rastiščih s skeletnimi, globljimi tlemi, Poo nemoralis-Quercetum dalechampii Šomšák et Háberová 1979, ki se razvije v zmerno odprtih sestojih v submontanskem pasu, Sorbo torminalis-Quercetum Svoboda ex Blažková 1962 pa uspeva na zmerno kislih tleh v sušnejših predelih. Glavna okoljska gradienta, ki vplivata na floristično sestavo, sta hranila v tleh in reakcija tal. Odražata se tako v Ellenbergovih indikatorskih vrednostih kot v merjenih okoljskih spremenljivkah (C/N razmerje in kislost tal). Poseben poudarek smo namenili diskusiji o vrstni sestavi in ekologiji rastišč.

Patterns of plant species richness and composition in deciduous oak forests in relation to environmental drivers

Local plant species richness and composition may vary across habitats and between plant taxonomic groups within temperate deciduous forests. Multi-taxon approach is therefore needed to provide a more detailed insight into determinants affecting vegetation structure. Fifty-four deciduous oak-dominated vegetation plots (20 m × 20 m) were sampled across central Slovakia (Stiavnicke vrchy Mts) in order to study the effect of environmental (soil, light, topographic) factors on species richness and composition patterns of two main assemblages of understorey layer (herb-layer vascular plants and ground-dwelling bryophytes). The number of recorded herb-layer vascular plants and ground-dwelling bryophytes was 12–48 (mean 28) and 0–11 (mean 4) species per plot, respectively. Generalized linear model revealed that species richness of herb-layer vascular plants was driven by canopy openness, altitude, soil pH/base saturation gradient and plant-available phosphorus. Canopy openness and heat load index accompanied by soil pH/base saturation gradient determined changes of the ground-dwelling bryophyte richness. Canonical Correspondence Analysis identified soil pH/base saturation gradient, canopy openness, soil silt and topography related predictors (altitude, slope, radiation) as the main drivers of the herb-layer vascular plant compositional variability. Species composition variation of ground-dwelling bryophytes was controlled by radiation and canopy openness.

BLACK ALDER DOMINATED FOREST VEGETATION IN THE WESTERN PART OF CENTRAL SLOVAKIA – SPECIES COMPOSITION AND ECOLOGY

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. Izvleček Gozdna vegetacija črne jelše dosedaj v nekaterih predelih Slovaške še ni bila dovolj raziskana. Članek predstavlja prvo vegetacijsko raziskavo fitocenoloških popisov in merjenih rastiščnih dejavnikov iz zahodnega dela osrednje Slovaške. Podatkovni niz smo klasificirali z modificiranim TWINSPAN algoritmom, s čemer smo lahko floristično in ekološko ločili značilne rastlinske združbe. Ugotovili smo asociaciji: Stellario nemorum- -Alnetum glutinosae Lohmeyer 1957 (obvodna črnojelševja na srednje do vlažnih rastiščih ob manjših potokih) in Carici acutiformis-Alnetum glutinosae Scamoni 1935 (evtrofna črnojelševja v kolinskem pasu) z dvema variantama Ligustrum vulgare in Galium palustre. Asociacijo Carici elongatae-Alnetum glutinosae Schwickerath 1933 (mezotrofni do eutrofni črnojelševi grezi, ki uspevajo na tleh stalno prepojenih z vodo), ki je dokumentirana samo z dvema popisoma smo določili na podlagi strokovnega poznavanja. Prikazali smo floristični in ekološki vzorec pojavljanja teh asociacij. Glavni gradienti so pojasnjeni na podlagi Ellenbergovih indikatorskih vrednosti, ekološki dejavniki pa so bili merjeni med terenskim vzorčenjem v vegetacijski sezoni 2011. Analiza glavnih komponent je razkrila pomen vlažnosti tal, svetlobe, deleža odprtih vodnih in talnih površin za variabilnost vrstne sestave na nivoju asociacij, medtem ko se varianti asociacije Carici acutiformis-Alnetum glutinosae ločita na gradientu kislosti.

Environmental conditions in relation to variability of deciduous forest vegetation — a study from volcanic mountain in central Slovakia

The deciduous forests represent dominant natural vegetation of Central European landscape and an important functional component for maintenance of biological diversity. However, their syntaxonomy and ecological gradients still remain unclear. The numerical classification was conducted to determine the main units of forest vegetation, while ordination techniques were used to explain the structure of vegetation-environmental data matrix consisting of 110 forest stands in the Štiavnické vrchy Mts (central Slovakia). Ten vegetation types within the phytosociological classes of deciduous forests Quercetea robori-petraeae and Querco-Fagetea were distinguished. The major environmental driver responsible for variation in forest species composition was interpreted as a response to soil moisture which also accounted for a large part of species variability (3.74%). Soil nutrient/acidity complex expressed by pH, Ca and Al concentration was also an important source of vegetation variability. Relevance of soil conditions in relation to plant survival and community distribution was discussed. Along the soil moisture gradient, vegetation types were arranged from the subxerophilous oak forests through the mesophilous beech and ravine forests to the hygrophilous alder ash vegetation.