Home – Home – Jornals – Flora and Vegetation of Asian Russia 2025 number 2

A new class of intrazonal sub-Arctic moderately mesophilous meadows - Polemonio borealis - Tanacetetea bipinnati Telyatnikov, Ermakov, Ermokhina et Khitun сlass nov. was described. The class represents the secondary communities occurring predominantly on eroded after wind deflation and well-drained sandy watersheds with the deep active layer of substrates in the sub-Arctic part of the tundra zone in Western and Central Siberia. They occupy also warm south-facing slopes of gulches and ravines on watersheds, lake or river terraces. The floristic peculiarity of the class is determined by the group of moderately xerophilous species originating from the xerothermic periods of the Pleistocene. Diagnostic species (D. s.) of the class: Armeria maritima, Campanula rotundifolia, Cerastium maximum, Dianthus repens, Draba hirta, Eremogone polaris, Festuca rubra subsp. arctica, Koeleria asiatica, Polemonium boreale, Potentilla stipularis, Rumex graminifolius, Salix nummularia, Silene paucifolia, Tanacetum bipinnatum, Thymus reverdattoanus . The class Polemonio borealis - Tanacetetea bipinnati includes one order Polemonio borealis-Tanacetetalia bipinnati Telyatnikov, Ermakov, Ermokhina et Khitun ord. nov. (with the same diagnostic species group as for the class) and two alliances. The alliance Oxytropido sordidae-Tanacetion bipinnati Telyatnikov et Prystyazhnyuk ex Telyatnikov, Ermakov, Ermokhina et Khitun all. nov. is the holotypus of the order. Syn.: Oxytropido sordidae-Tanacetion bipinnati Telyatnikov et Prystyazhnyuk 2012 nom. inval. [art. 5a, ICPN]. Diagnostic species of the alliance are Aconogonon ochreatum, Androsace septentrionalis, Artemisia borealis, Antennaria villifera, Castilleja arctica, Cerastium arvense, Festuca ovina, F. rubra, Oxytropis sordida, Equisetum pratense, Solorina crocea . Holotypus of the Oxytropido sordidae-Tanacetion bipinnati all. nov. is the association Armerio maritimae-Polytrichetum alpini Ermokhina ass. nov. (described in this paper). The alliance range spreads throughout the sub-Arctic zone and the southern part of the Arctic zone in Western Siberia. The alliance community represents the advanced stages of the primary succession of vegetation on flat wind-eroded sandy surfaces or on well-drained slopes of hills and river or lake terraces. Herb species predominate, but sometimes dwarf-shrubs ( Salix nummularia, Arctous alpina, Dryas octopetala subsp. subincisa ) are abundant as well. Moss-lichen layer is poorly developed. The alliance includes 5 associations: Diantho repentis-Festucetum ovinae Telyatnikov et Prystyazhnyuk 2012, Cerastio maximi-Salicetum nummulariae Telyatnikov et Prystyazhnyuk 2012, Antennario lanatae-Arctoetum alpinae Telyatnikov et Prystyazhnyuk 2012, Armerio maritimae-Polytrichetum alpini Ermokhina ass. nov., Koelerio asiaticae-Salicetum nummulariae Dudov et Ivleva nov. prov.) and 1 subassociation ( A.l. - A.a. subass. lagotidoetosum minoris Telyatnikov et al. 2019). Ass. Armerio maritimae-Polytrichetum alpini Ermokhina ass. nov. (Table, rel. 1-10, Table, Column 4). Holotypus: releve nr. 4 in Table (Field releve nr. Ks_31). Diagnostic species: Armeria maritima, Artemisia borealis, Briocaulon divergens, Cetraria odontella, Polytrichastrum alpinum s.l., Rumex graminifolius, Stereocaulon paschale . The association is recorded in the typical tundra subzone of the Yamal Peninsula. They occupy flat eroded parts of sandy watersheds and gentle (5°) well-drained south-western slopes of small hills at altitudes of 16-67 m. The herb layer is well-developed (mean height is 10-20 cm and coverage is 35-80 %). The lower ground layer is formed by dwarf-shrubs (cover of up to 30 %), mosses (mean cover is of 10-30 %, sometimes up to 40 %) and lichens (mean cover is 15-35 %). The alliance Erigerono eriocephali-Artemision tilesii Telyatnikov, Ermakov, Ermokhina et Khitun all. nov. (described in this paper). Diagnostic species: Arnica iljinii, Artemisia tilesii, Astragalus umbellatus, Erigeron eriocephalus, Festuca viviparoidea, Pedicularis verticilla, Saxifraga tenuis, Taraxacum macilentum, Tephroseris heterophylla . Communities of the alliance occur in tundra zone of the western part of the Taimyr and Gydan Peninsulas. They occupy the well-insolated eroded habitats with shallow snow cover. Grounds are loamy to sandy-loamy with moderate drainage. The herb layer is well-developed whereas cover of moss-lichen layer is much lower. Holotypus of the alliance is the association Pedicularido verticillatae-Astragaletum arctici Zanokha 1993 (Zanokha, 1993, p. 112). Diagnostic species of the association are Astragalus alpinus subsp. arcticus, Erigeron eriocephalus, Festuca vivipara, Pedicularis verticillata, Hedysarum hedysaroides, Potentilla stipularis, Arnica iljinii, Silene paucifolia, Bistorta major s.l. The association was described by L. Zanokha (1993) in tundra zone of the western part of the Taimyr Peninsula (the mouth of the Uboinaya River). The community occurs on steep (40-45°) southern slopes with sandy-loamy or loamy soil (pH is close to neutral). The coverage of herbaceous layer is 70-100 %. The moss-lichen layer is not developted. The subass. P.v.-A.s. typicum (Tabl. 1, column 8, 9) is represented by three subzonal variants (vicariants): typicum, campanulosum rotundifoliae and potentillosum hyparcticae (Zanokha, 1993). The diagnostic species of the subass. P.v.-A.a. trisetosum litoralis Telyatnikov et al. 2019 (Tabl. 1, column. 7) are Bistorta elliptica, Draba hirta, Oxyria digyna, Trisetum sibiricum subsp. litorale . This community was described from the northern part of the typical tundra subzone in the Gydansky Peninsula. It occupies steep well drained south-facing slopes of hills.