Study of the vascular plants diversity in the surroundings of the Kytalyk Research Station (Arctic Yakutia)

The local flora (LF) surrounding the research station at the Kytalyk Resourse Reserve was studied in detail and an annotated checklist is presented. Species composition of Kytalyk area flora is compared with the LF in three neighboring areas in the lower reaches of the Indigirka River. These localities had differing topography, therefore their species richness varied. The LF of the Kytalyk Research Station area numbered 131 vascular plant species from 66 genera and 28 families. Low species richness is explained by the prevalent flat and homogenous lowland topography. We found new and the northernmost in this region locations of several boreal and hypoarctic species (Moehringia lateriflora, Salix myrtilloides, Alnus fruticosa, Polygonum tripterocarpum, Orthilia obtusata, Pedicularis pennellii, Utricularia intermedia, U. minor, Triglochin maritima). The taxonomic structure of all four floras is similar, however in the Kytalyk area the Fabaceae, Lycopodiacea and Gentianaceae families were not found, whereas the proportion of Salicaceae, Caryophyllaceae and Scrophulariaceae was higher than in the other LF. We estimated species behavior with landscape activeness scores. Non-active stenotopic species with low abundance comprise 42% of the flora and species with broad-ecological tolerance comprise 18% of the flora. Phytogeographical latitudinal groups (arctic, hypoarctic and boreal) are almost equally represented in the LF. Geographical and taxonomic structure of the LF confirm its position in the bioclimatic subzone D.