Home – Home – Jornals – Flora and Vegetation of Asian Russia 2024 number 3

On the territory of the Tomsk Region there is a group of species that have isolated locations, low numbers, are characterized by a narrow ecological amplitude and are located on the border of their range. However, they do not have conservation status and require additional research. In this regard, studies were carried out on three local cenopopulations of Nepeta nuda in the south of the Tomsk Region. N. nuda is a Eurasian meadow-steppe species. This is a perennial herbaceous taproot sympodially growing polycarpic plant with an elongated erect shoot, a hemicryptophyte. For the studied species, the phytocenotic location was established, the seasonal rhythm of development, morphological parameters, ontogenetic structure and seed productivity were studied. The influence of the anthropogenic factor on the stability of a rare species in natural habitats was studied. It has been established that the northern boundary of the species’ distribution lies in the south of the Tomsk Region (Kozhevnikovsky district). The habitats of the species are limited mainly to moderately steep and gentle slopes of southern exposure, occupied by steppe meadows. The species was recorded as part of forb-grass, forb-reed grass and forb-sedge plant communities. The floristic composition of phytocenoses with the participation of N. nuda is quite depleted and is represented by 18-30 species. The density of N. nuda individuals in the surveyed areas remains quite low, varying between 1.38-3.50 individuals/m². The ontogenetic composition of cenopopulations is characterized by incompleteness: there are no individuals at the initial stages of ontogenesis or, in general, this group is poorly represented. Also, no individuals in the senile state were found in any of the coenopopulations. The main way to renew and maintain the number of species in nature is seed propagation. However, due to significant damage to fruits and seeds by insect pests, the seed productivity of the species, according to some indicators, is reduced by more than half. Seed germination remains below average. There is no vegetative propagation. As a result of the data obtained on the distribution and state of coenopopulations of N. nuda in the south of the Tomsk Region, we consider it necessary to recommend this species for inclusion in the next edition of the Red Book of the Tomsk Region with rarity status 3 - a rare species, on the border of its range.