Original paper

Extrazonal steppes and other temperate grasslands of northern Siberia − Phytosociological classification and ecological characterization

Reinecke, Jennifer; Troeva, Elena; Wesche, Karsten

Phytocoenologia Band 47 Heft 2 (2017), p. 167 - 196

44 references

published: Jul 20, 2017
published online: Jul 21, 2017
manuscript accepted: Mar 31, 2017
manuscript revision received: Jan 16, 2017
manuscript revision requested: Mar 27, 2017
manuscript received: Dec 1, 2016

DOI: 10.1127/phyto/2017/0175

BibTeX file

O

Open Access (paper can be downloaded for free)

Download paper for free

Abstract

Abstract Aims: Isolated outposts of eastern steppe vegetation (Cleistogenetea squarrosae and physiognomically related syntaxa) can be found on south-exposed slopes in the tundra and taiga zone of northern Siberia. They are considered relics of the Pleistocene cold steppe, but a number of Russian geobotanical studies reveal how these steppes differ among each other in floristic composition and environmental conditions. We aim at providing an overview of current phytosociology of northern Siberian steppes and co-occurring temperate grasslands through literature review and classification of our own data. Study area: Central and northeastern Yakutia, Russia. Methods: Phytosociological classification of 210 relevés of meadow, steppe and tundra steppe vegetation using the Braun-Blanquet approach; samples were further characterized using macro- and microclimatic variables. Results: We found true steppes of the Stipetalia krylovii up to Central Yakutia and meadow steppes of the Festucetalia lenensis as far as northeastern Yakutia. Both are restricted to south-exposed slopes, with slope steepness increasing towards the north, compensating for a colder and wetter macroclimate. Both orders include typical (Stipetum krylovii, Pulsatillietum flavescentis) and petrophytic (Elymus reflexiaristatus community, Carici duriusculae-Festucetum lenensis) associations or communities, with meadow steppes additionally containing a unique cryophytic association (Astragalo pseudoadsurgenti-Calamagrostietum purpurascentis). So called tundra steppes occur north of the tree line. They belong to the class Carici rupestris-Kobresietea bellardii, and their occurrence is more related to disturbance than to slope exposure or inclination. Conclusions: Steppe vegetation of the Cleistogenetea squarrosae occurs as far north as the taiga zone of northeastern Yakutia, but tundra steppes are not steppes in the true sense, despite similar physiognomy and the contribution of xerophytes. This distinction is important when trying to find modern analogues of Pleistocene cold steppes.
 Nomenclature: The Plant List (http://www.theplantlist.org/), accessed 2010.
 Abbreviations: DCA = Detrended Correspondence Analysis; DIR = Direct incident radiation.
 Submitted: 1 December 2016; first decision: 16 January 2017; accepted: 31 March 2017


Keywords

Carici rupestris-Kobresietea bellardiiCleistogenetea squarrosaecryophytic steppeextrazonal steppeFestucetalia lenensisStipa kryloviiStipetalia kryloviiMammoth steppeMolinio-Arrhenathereteanorthern Siberiaphytosociological classificationtundra steppe