Anthropogenic vegetation in the Baikal Siberia

The article synthesises the data on anthropogenic vegetation in the Baikal Siberia. Information is given on the basis of 228 relevés made from 2014 to 2020 in settlements and their surroundings in the Irkutsk Oblast and the Republic of Buryatia (Fig. 1) and previously published information by M. Chytrý, P. Pešout, L. Klimeš, A. R. Ishbirdin, V. V. Chepinoga. According to the results of our work, the anthropogenic vegetation in the Baikal Siberia is represented by 7 classes, 8 orders, 10 alliances, 28 associations and 11 communities. Most syntaxa are widely distributed in the Europe and in the Asian part of Russia. One order, 2 alliances and 8 associations are described as new (Table 1). Within the class Sisymbrietea Gutte et Hilbig 1975 (the order Sisymbrietalia sophiae J. Tx. ex Görs 1966 and the alliance Atriplicion Passarge 1978), five associations are identified: Chenopodietum stricti (Oberdorfer 1957) Passarge 1964, Atriplicetum nitentis Slavnić 1951, Conyzo canadensis–Lactucetum serriolae Lohmeyer in Oberdorfer 1957 (variants Lactuca serriola, Conyza сanadensis), Matricarietum perforatae Kępczyński 1975, Sisymbrietum loeselii Gutte 1972 (Table 2, Figs. 2–7). The class Artemisietea vulgaris Lohmeyer et al. in Tx. ex von Rochow 1951 includes two orders. The order Onopordetalia acanthii Br.-Bl. et Tx. ex Klika et Hadač 1944 is presented by two alliances. Three associations are established in the alliance Onopordion acanthii Br.-Bl. et al. 1936 (Table 3, Figs. 8–10): Axyrido–Carduetum nutantis Ishbirdin et Solomeshch in Ishbirdin et al. 1988 and two new ones: Artemisietum sieversianae Belova et Arepieva ass. nov., Artemisio sieversianae–Urticetum cannabinae Chepinoga et Arepieva ass. nov. The new associations, that unite communities dominated by Artemisia sieversiana and Urtica cannabina, are widely distributed in the region on wastelands, roadsides and near buildings. Three associations Poo compressae–Tussilaginetum farfarae Tx. 1931, Picrido–Pastinacetum sylvestris Solomeshch in Ishbirdin et al. 1988 and Melilotetum albo–officinalis Sissingh 1950 are placed in the second alliance Dauco-Melilotion Görs ex Rostański et Gutte 1971 (Table 4, Figs. 11–13),. One alliance (Convolvulo arvensis–Agropyrion repentis Görs 1967) with three associations (Convolvulo arvensis–Brometum inermis Eliáš 1979, Linario acutilobae–Medicaginetum falcatae Chepinoga et Arepieva ass. nov., Plantagini depressae–Hordeetum jubati Belova et Arepieva ass. nov., distributed on wastelands and roadsides (Table 5, Figs. 14–15) are revealed within the order Agropyretalia intermedio–repentis T. Müller et Görs 1969 (the class Artemisietea vulgaris). There are also the basal communities of Dactylis glomerata [Agropyretalia intermedio–repentis] (Table 5, Fig. 16) and of Artemisia vulgaris (Table 5, Fig. 17) within the class Artemisietea vulgaris. The order Arctio lappae–Artemisietalia vulgaris Dengler 2002 (the class Epilobietea angustifolii Tx. et Preising ex von Rochow 1951), includes new alliance Arctio tomentosi–Urticion cannabinae Chepinoga et Arepieva all. nov., which has differences from the known alliance Arction lappae Tx. 1937 (Table 6, Fig. 18). The new alliance comprising ruderal communities of nitro- and mesophylic species in shaded habitats in the Baikal Siberia includes three associations: Arctio tomentosi–Urticetum cannabinae Chepinoga et Arepieva ass. nov. (Table 7, Fig. 19), Arctio tomentosi–Impatientetum glanduliferae Chepinoga et Arepieva ass. nov. (Table 7, Fig. 20), Arctio tomentosi–Urticetum dioicae Belova et Arepieva ass. nov. (Table 9, Fig. 21). The difference between the ass. Arctio tomentosi–Impatientetum glanduliferae and Arctio tomentosi–Urticetum dioicae from the ass. Calystegio sepium–Impatientetum glanduliferae, Leonuro–Arctietum tomentosi, Leonuro–Urticetum dioicae established in Europe are shown in Table 8, 10 and Fig. 22. The communities Geranium sibiricum, Ranunculus repens, Stellaria media, Chelidonium majus, Calamagrostis langsdorffii are identified (Table 9, Figs. 23–24) within the class Epilobietea angustifolii The class Puccinellio–Hordeetea jubati Mirkin in Gogoleva et al. 1987 is represented by the ass. Puccinellio hauptianae–Hordeetum jubati (Gogoleva et al. 1987) Czerosov et al. 2005 (Table 10, Fig. 25)t within the order Puccinellio–Hordeetalia jubati Gogoleva et al. 1987 and the alliance Puccinellio–Hordeion jubati Gogoleva et al. 1987. New order Hippophaetalia rhamnoidis Chepinoga et Arepieva ord. nov. and alliance Poo angustifoliae–Hippophaeion rhamnoidis Chepinoga et Arepieva all. nov. with the ass. Poo angustifoliae–Hippophaetum rhamnoidis Chepinoga et Arepieva ass. nov. are estanlished (Table 10, Fig. 26) within the class Robinietea Jurco ex Hadač et Sofron 1980. These syntaxa unify communities dominated by Hippophaё rhamnoides, formed on drained soils and substrates in anthropogenic and severely disturbed natural habitats: roadsides, wastelands, embankments, dumps, quarries, sandy and gravel banks of artificial and disturbed water bodies in Siberia and continental regions of Eastern Europe. The occurrence of syntaxa of anthropogenic vegetation in various regions of Baikal Siberia (Table 11) demonstrates that more complete data are currently available for the Irkutsk Oblast, while the Republic of Buryatia and the Zabaikalsky Krai are obviously needed by more intensive research. The communities of associations Chenopodietum stricti and Atriplicetum nitentis are the most common in recently disturbed anthropogenic ecotopes in the Baikal Siberia; these of associations Axyrido–Carduetum nutantis, Artemisietum sieversianae, Artemisio sieversianae–Urticetum cannabinae, Convolvulo arvensis–Brometum inermis, and Plantagini depressae–Hordeetum jubati are widespread on wastelands and roadsides; while communities of associations Arctio tomentosi–Urticetum cannabinae and Arctio tomentosi–Urticetum dioicae are often formed in shady habitats. The shrub ass. Poo angustifoliae–Hippophaetum rhamnoidis is also widespread in the region. About a quarter of items in Prodromus which are represented by rank-less communities, might be established as distinctive associations as new data accumulate. In addition, specific communities formed by Central and East Asian species (e.g., Elymus dahuricus, Eragrostis spp., Neopallasia pectinata, etc.) are possinly to be described on the territory of the Republic of Buryatia and Zabaikalsky Krai. The presented research results summarize the accumulated information on the ruderal vegetation in the Baikal Siberia and propose new tasks for studying its diversity and distribution.