Fig 2 - uploaded by Nikolay Velev
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Ordination diagram of the analyzed data set along the first two DCA axes
Source publication
In this study the phytocoenoses of Petasites albus, P. hybridus and P. kablikianus were investigated on the territory of Bulgaria and Romania. Numerical classification and ordination were performed by PC-ORD and JUICE software packages. Diagnostic species were determined by calculating the Phi-coefficient. Three associations of the Petasition offic...
Context in source publication
Context 1
... The three types of vegetation communities inhabit ecologically similar conditions (Fig. 2). The first axis (eigenvalue = 0.425, gradient length: 4.166) in the diagram can be related to the humidity level of the communities. Hydrological conditions are changing periodically during the vegetative period, as far as the associations of Petasitetum albae and Petasitetum hybrido-kablikani are concerned. On the contrary, these ...
Citations
... Recently, only vegetation dominated by Petasites sp. pl. was investigated (Nazarov et al. 2022). However, there are also studies following the Russian dominance-based approach dealing with this vegetation, as this approach was historically widely used in Bulgaria (Apostolova and Slavova 1997). ...
... In the Petasitetum albi, species typical of southeastern Europe (e.g. Telekia speciosa, Ranunculus serbicus) occur (Nazarov et al. 2022). These species are mainly shade-and nutrient-demanding. ...
... many species occurring in the forest belt. Roussakova (2000) distinguished in her work three associations of the class Mulgedio-Aconitetea: Angelico sylvestris-Heracleetum verticillati, Carici lazarei-Deschampsietum cespitosae and Senecioni rupestris-Rumicetum alpini, same vegetation types are accepted in national compilation of Tzonev et al. (2009). Nazarov et al. (2022 distinguished one plot of Petasitetum kablikiani in Bulgaria, which we are missing in the analyzed dataset. European distribution of higher syntaxa provided by Preislerová et al. (2022) distinguish in Bulgaria only two alliances: Cirsion appendiculati and Rumicion alpini, however, they predict in the area numerous other alliances. Table ...
Class Mulgedio-Aconitetea comprises plant communities that develop primarily in the upper montane to subalpine vegetation belts. It is vegetation where tall herb species (forbs, ferns, grasses) occur dominantly; in the Balkans, it was studied only marginally. In this article, based on floristic composition we assess two questios: (1) how diverse is the class Mulgedio-Aconitetea in Bulgaria and (2) what
environmental factors are responsible for the vegetation assemblages in the area? We analyzed 387 plots. We created an expert system that classifies this vegetation and tested environmental variables for their influence on these vegetation types. In total, 15 associations and one uncategorized community were classified using the Braun-Blanquet approach. The length of the growing season (number of growing degree days > 0°C) and climate moisture have a significant effect on the vegetation. Disturbance severity, disturbance frequency and reaction have influence over the species scores. Moreover, all variables significantly differ between the vegetation types.
