Paulina Wietrzyk-Pełka podpisana: Paulina Wietrzyk

Arctic vegetation still lacks a uniform system to classify its plant communities, the current arrangement of the phytosociological data being difficult to interpret. However, using modern methods, it has proved possible to organize the current data to create a suitable system based on numerical algorithms (detrended correspondence analysis and cluster analysis) and traditional methods for 135 phytosociological relevés from snowbed and exposed ridge habitats of Svalbard; 125 relevés were selected from twentieth and early twenty-first century publications, and ten relevés were collected by our group in 2012 from the Kaffiøyra Plain (Oscar II Land, NW Spitsbergen). Our analysis has shown there to be four associations and one community. Two associations and one community are distinguished within the Luzulion arcticae Gjærev. 1950: (1) the Pedicularietum hirsutae ass. nov., (2) the Deschampsietum alpinae (Nordh. 1943) Węgrzyn and Wietrzyk 2015 stat. nov., and (3) the Minuartia biflora community. Two syntaxa were assigned to the Luzulion arcuatae Elvebakk ex Węgrzyn and Wietrzyk 2015: (4) the Anthelietum juratzkanae Kobayashi ex Węgrzyn and Wietrzyk 2015 with a confirmed status and (5) the Gymnomitrietum coralloidis Hadač ex Węgrzyn and Wietrzyk 2015 stat. nov. was described by means of a new approach.