Invasive Species of Segetal Communities of the Southern and Middle Urals

Abstract

The invasive component of the cenoflora of segetal (field weed) communities of the Southern Urals and adjacent territories (Republic of Bashkortostan, Perm krai, and Orenburg oblast) was analyzed. A total of 33 invasive species were identified, which is 11.3% of the entire cenoflora of segetal communities. Analysis of species distribution in the syntaxonomic space of segetal vegetation showed that invasive species occur in 17 syntaxa corresponding to the rank of the association. The number of invasive species in them ranges from 1 to 16. Most of the recorded invasive species are xenophytes (Rhaponticum repens, Amaranthus albus, Ambrosia psylostachya, Artemisia sieversiana, Ceratocarpus arenarius, Cyclachaena xanthiifolia, Bassia scoparia, Iva xanthiifolia, Sisymbrium volgense, Xanthium orientale, etc.) and have high values of constancy and activity in the southern part of the gradient—in the steppe and the southern part of the forest-steppe zone. A small group of ergasiophytes (Heracleum sosnowskyi, Lupinus polyphyllus, Galega orientalis, etc.) gravitates to the northern part of the gradient to the forest and the northern part of the forest-steppe zone. The leading ecological factors of invasive species distribution are shading/lighting, temperature regime, and climate continentality. The most invasive communities of the region’s segetal vegetation and peculiar “corridors” for the advancement of some invasive species from south to north are the communities of Orenburg oblast, which represent two associations Amarantho blitoides–Lactucetum tataricae Khasanova et al. 2019 and Lactucetum tataricae Rudakov in Mirkin et al. 1985.