Communities of annual halophytes (Thero-Salicornietea) in Transbaikalia (Eastern Siberia)
Korolyuk, Andrey Y.; Anenkhonov, Oleg A.; Chepinoga, Victor V.; Naidanov, Bulat B.
Communities of annual halophytes (Thero-Salicornietea) in Transbaikalia (Eastern Siberia) Abstract Aims: Communities of annual halophytes belonging to the class Thero-Salicornietea at the eastern edge of the class distribution in Russia have been studied. Throughout the area under study, steppe and forest-steppe landscapes dominate, and many salty lakes are scattered within. The salinization process is commonly confined to surroundings of those lakes, but salty soils also exist at the dry bottoms of intermountain depressions. This paper aims at classifying the Thero-Salicornietea of the region according to the Braun-Blanquet approach. Location: Transbaikalia, Eastern Siberia, Russia. Methods: We collected 200 phytosociological relevés and classified them with UPGMA clustering. NMDS ordination was used to analyze the relationship between species composition, ratio of xerophytes vs. mesophytes and annual vs. perennial plants, and further applied for assessment of ecological relations among the syntaxa. Results: The class Thero-Salicornietea in Transbaikalia was found to comprise six associations, united in two alliances and one order. All of these units are newly described according to International Code of Phytosociological Nomenclature. In most cases species restricted to the territory of Asia have been selected as diagnostic taxa, including Suaeda sibirica, S. heteroptera, S. corniculata subsp. mongolica, Atriplex fera, and Artemisia anethifolia. The new order Suaedetalia sibiricae represents annual succulent halophytes vegetation of irregularly flooded saline habitats of the south of Eastern Siberia and Central Asia. The alliance Suaedion sibiricae represents the South Eastern Siberian and Central Asian vicariant of the Camphorosmo-Suaedion corniculatae. Asian species of Suaeda are common dominants in communities of the alliance, and Salicornia perennans also can dominate, but seldom does. The alliance Artemision anethifoliae represents relatively xerophytic communities and has only one association described so far. All newly described syntaxa reflect the peculiarity of the annual halophyte vegetation in Transbaikalia in particular and in the southern part of Eastern Siberia and Central Asia in general. Keywords: Braun-Blanquet approach; halophytic; halophytic vegetation; new syntaxon; semiarid region; Siberia; Suaedetalia sibiricae; syntaxonomy; Thero-Salicornietea; Transbaikalia. Nomenclature: Cherepanov (1995) for vascular plants, except Lomonosova & Freitag (2008) for Suaeda. Abbreviations: ICPN = International Code of Phytosociological Nomenclature (Weber et al. 2000); NMDS = Nonmetric Multi-Dimensional Scaling (Kruskal 1964). Submitted: 30 May 2016; first decision: 28 July 2016; accepted: 14 October 2016 Co-ordinating Editor: Monika Janišová