Monitoring the state of Herminium monorchis (Orchidaceae) cenopopulation in Olshanskiy solonetz (Penza region) 

Yuliya A. Fatyunina, Candidate of biological sciences, associate professor, associate professor of the sub-department of general biology and biochemistry, Penza State University (40 Krasnaya street, Penza, Russia), E-mail: vyal81@mail.ru
Galina F. Mozhaeva, Biologist, Penza Botanical Garden named after I.I. Sprygin, Penza State University (40 Krasnaya street, Penza, Russia), E-mail: mozhaeva-1965@mail.ru
Oksana E. Surkova, Teacher of biology, Secondary School No.71 (1 Mozhaiskogo street, Penza, Russia), E-mail: m sur-ok1967@mail.ru 

Background. Herminium monorchis (L.) R. Br. – rare species of the Orchid family, included in the Red Book of Penza region. Monitoring of the cenopopulation of the species on the Olshansky solonetz is necessary to assess the current state and forecast in order to preserve it. Materials and methods. H. monorchis develops on soils of varying degrees of salinity in the composition of meadows of different types on the Olshanskiy solonetz. In 2013, 2021, 2023 geobotanical descriptions were made, the ontogenetic structure was studied, and the ecological density of the cenopopulation, the Δ and ω indices were determined. Results. The area of the H. monorchis cenopopulation on the Olshanskiy solonetz has not decreased over 10 years of observations. The species is confined to associations of saline and steppe meadows formed by Centaurea jacea, Equisetum arvense, Inula salicina, Senecio schvetzovii, Ononis arvensi, Calamagrostis epigeios, Thalictrum simplex. At low salinity, H. monorchis plays the role of an assector in them. With an increase in the degree of salinity, its participation in the composition of plant communities increases – it becomes a co-dominant and dominant. The ecological density of the cenopopulation is very high, increasing with increasing salt content. Population is normal. Ontogenetic spectra in 2013 are righthanded, with a predominance of generative individuals, in 2023 they are bimodal with a maximum on generative ones on immature plants. Self-maintenance of the population occurs mainly due to vegetative reproduction, which ensures the rejuvenation of individuals to the immature age state, and to a lesser extent by seed (a low proportion of juvenile individuals). A high renewability index indicates the stability of the population due to efficient reproduction. Indices of age and efficiency are typical for maturing and mature populations. Among the generative individuals, plants of reduced and low vitality predominate due to the toxic effect of salts. The life form of a vegetative annual allows the species to increase its competitiveness in saline conditions compared to other meadow grasses. Conclusions. The condition of the H. monorchis cenopopulation at the Olshanskiy solonetz is relatively favorable. Further monitoring of the state of the cenopopulation should be continued in order to timely identify possible adverse changes. 

ontogenetic structure, rare plants, vitality structure, vitality, salinity, pseudohalophytes, vegetative propagation, density 

Fatyunina Yu.A., Mozhaeva G.F., Surkova O.E. Monitoring the state of Herminium monorchis (Orchidaceae) cenopopulation in Olshanskiy solonetz (Penza region). Izvestiya vysshikh uchebnykh zavedeniy. Povolzhskiy region. Estestvennye nauki = University proceedings. Volga region. Natural sciences. 2024;(1):28–38. (In Russ.). doi: 10.21685/2307-9150-2024-1-3