Variability of alder-dominated forest vegetation along a latitudinal gradient in Slovakia

Abstract

Syntaxonmical revision of azonal forest vegetation with dominance of <em>Alnus glutinosa </em>and <em>A. incana </em>was done along a latitudinal transect of Slovakia. A data matrix consisting of 240 phytosociological relevés was obtained in accordance with the standard Zürich-Montpellier approach. Detrended correspondence analysis was used to clarify the relationships between the vegetation composition and environmental variables, whereas one-way ANOVA was applied to quantify the differences in site requirements of particular vegetation types. The unsupervised numerical classification resulted in identification of five clusters corresponding to the traditionally described and ecologically interpretable associations within the Euro-Siberian alder carr forests of <em>Alnion glutinosae </em>and the European broad-leaved floodplain forests of <em>A</em><em>lnion incanae</em>: <em>Carici elongatae-Alnetum glutinosae </em>Schwickerath 1933 (alder carr forests on permanently waterlogged soils), <em>Stellario-Alnetum glutinosae </em>Lohmeyer 1957 (riparian alder vegetation on mesic to humid sites along small brooks), <em>Piceo-Alnetum </em>Mráz 1959 (submontane and montane oligotrophic spruce-alder forests on waterlogged habitats), <em>Cardamino amarae-Alnetum incanae </em>Šomšák 1961 (grey alder vegetation in spring fed areas) and <em>Alnetum incanae </em>Lüdi 1921 (submontane and montane streamside grey alder forests on mesic sites). They significantly (<em>P </em>< 0.05) differed in the Ellenberg's indicator values for nutrients, moisture, temperature and altitude. These environmental variables were also established by DCA analysis as underlying sources of variation in alder-dominated forest composition. Special attention was given to discussion of their syntaxonomy, nomenclature, floristic structure, ecological features and distribution

Ellenberg’s indicator values for soil nitrogen concentration and pH in selected swamp forests in the Central Black Sea region of Turkey

“…pH values for the studied species ranged from 6 to 7, whereas soil nitrogen values ranged from 7 to 8. EIVs for soil N concentration and pH in the present study were similar to those reported for other swamp forests (Slezák et al, 2012). The studied species were indicators of weakly acid to weakly basic and indicated fertile soils with high bioactivity and alkaline and near neutral pH (Vallet et al, 2008).…”

Numerical classification of alder carr and riparian alder forests in Slovakia

“…This proposal, which was also adopted by Seibert (1992), highlighted the need of more complex analysis and most likely resulted from unclear relations between the Carici remotae-Fraxinetum excelsioris and group of syntaxa described from Carpathian region within a few years of each other, namely Cardamino amarae-Alnetum incanae Šomšák 1961, Caltho laetae-Alnetum incanae (Zarzycki 1963) Stuchlik 1968 and Caltho laetae-Alnetum glutinosae Šomšák (1961) 1979(see also Pancer-Kotejowa 1973. The last name represents a younger homonym of the Caltho palustris-Alnetum glutinosae Šomšák 1961 (ICPN § 31) which has heterogeneous syntaxonomic content (Slezák et al 2013). The phytosociological material in original diagnoses of two remaining associations is very similar in overall floristic spectrum (Šomšák 1961, Zarzycki 1963, Stuchlik 1968).…”

Changes in Species Composition in Alder Swamp Forest Following Forest Dieback

“…Due to the significant fluctuations in the groundwater table, the spatial structure of alder carr stands may be remarkably diverse and consist of two contrasting microhabitats, which are hummocks and hollows [16,17]. Hummocks are formed by adventitious roots of black alder and are elevated above the annual peak of the water table fluctuations [18].…”