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The objective of this study was to compare ecophysiological and morphological parameters of a regionally endangered orchid species, Epipactis atrorubens (Hoffm. ex Bernh.) Bess., growing in two forest communities (on serpentine and granite outcrops) of the Middle Urals, Russia. Biodiversity, dominance, and phytocoenosis studies showed the colonization of a wide range of plant species on both sites. The physicochemical properties of the soil, chemical composition and morphological features of E. atrorubens, growing under technogenic conditions (asbestos deposits), on serpentine outcrops and in the natural environment of the granite massif were studied for the first time. The serpentine substrate differed from the granite one by its greater stoniness, circumneutral pH and lower contents of available nitrogen and phosphorus. Extremely high concentrations of magnesium were found in the serpentine soil, some 79 times higher than in the granite substrate. High concentrations of nickel (94 times), chromium (59 times), cobalt (17 times), and iron (4 times) were found in the serpentine substrate, higher than in the granite substrate. The differences between the sites for available metal contents and for root and shoot metal contents were significantly less. Concentrations of most of the metals in the roots were higher than in the shoots. Despite higher metal concentrations and lower nitrogen and phosphorus levels in serpentine soils, E. atrorubens had a larger population and greater viability compared to those growing on granite. Plants on serpentine outcrops were characterized by the formation of a larger number of fruits, greater root lengths and thicker leaf blades, compared to plants on granites. The well-developed orchid mycorrhizae contributed to the survival of this species under unfavorable serpentine conditions. Hence, serpentine outcrops formed due to the mining of asbestos could be a suitable substrate for the light-demanding E. atrorubens due to its capacity to adapt to dry, rocky, nutrient-depleted soils and limited competition from other plants.

In previous decades, some species of the Orchidaceae family have been found growing in man-made habitats. Neottia ovata is one of the most widespread orchids in Europe, however it is quite rare in Russia and is included in several regional Red Data Books. The purpose of this study was to compare the chemical composition and morphophysiological parameters of N. ovata from two forest communities of the Middle Urals, Russia: natural and transformed (fly ash dump of Verkhnetagil’skaya Thermal Power Station) for determining orchid adaptive features. The content of most of the studied metals in the underground parts (rhizome + roots) of N. ovata was considerably higher than in the leaves, which diminished the harmful effect of toxic metals on the aboveground organs. The adaptive changes in the leaf mesostructure of N. ovata such as an increase in epidermis thickness, the number of chloroplasts in the cell, and the internal assimilating surface were found for the first time. The orchids from the fly ash deposits were characterized by a higher content of chlorophyll b and carotenoids than plants from the natural forest community that evidenced the compensatory response on the decrease in chlorophyll a. The ability of N. ovata from the transformed habitat to maintain a relatively favorable water balance and stable assimilation indexes further contribute to its high viability. The study of orchid adaptive responses to unfavorable factors is necessary for their successful naturalization and introduction into a new environment.

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Ash dumps occupy significant areas around the world and make a negative influence on the environment. This effect is decreased by their natural colonisation determined by the bioclimatic conditions of the area. The purpose of the current study was to identify the structure of the forest communities and the initial stages of soil formation on the ash dump in southern taiga.This study was carried out on three sites in the forest phytocoenosis formed in the process of revegetation of the Verkhniy Tagil Power Station ash dump over 50 years, as well as on two background forest sites in the Middle Urals. Complex geobotanical and soil studies were carried out.The results of the study show that forest phytocoenoses with a predominance of hardwood species (Betula pendula Roth and Populus tremula L.) and a small admixture of coniferous species can form on the non-recultivated ash dump within 50 years in a boreal zone. In total, the studied mixed forest phytocoenoses are similar in composition to zonal secondary forests, but differ by having lower height and diameter of the stand, as well as herb–shrub layer coverage. Their species density and floristic richness are also lesser. The study proved that the process of soil formation is also proceeding according to the zonal type in the ash substrate under forest communities. The results of the study can be applied to justifying the forecasts of ecosystem restoration on the technogenic substrate, as well as for the species selecting for their recultivation in the studied area and similar to it.

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The representatives of the family Orchidaceae Juss. are often used as a source of natural antioxidants, including phenolic compounds, which play an important role in plant resistance under stressful conditions. This study investigates the content of lipid peroxidation products and soluble phenolic compounds in flowering plants of Platanthera bifolia (L.) Rich. growing in natural (forest park) and transformed (fly ash dumps of Thermal Power Stations) ecosystems of the Middle Urals, Russia, as well as the content of flavonoids at different stages of orchid development. Research has shown that in disturbed habitats, P. bifolia is capable of forming abundant populations containing a significant portion of the flowering plants. Additionally, flowering orchids from fly ash dumps contained an average 20 % more lipid peroxidation products, which indicated a shift in the redox balance towards oxidative processes. An increase by 2.4 times on average in the content of phenolic compounds, particularly flavonoids, was observed at all developmental stages of the plants growing in the transformed ecosystems. Regardless of the growing conditions, the non-flowering mature individuals were characterized by a minimum content of flavonoids, probably due to pre-generative metabolic restructuring. Yet, in the period of orchid blooming, the flavonoid content in their leaves increased again in all study sites. At the same time, the flavonoid proportion of the total soluble phenolic compounds was 42 % in the natural habitat, increasing to 66 % on average in the transformed ecosystems. Thus, flavonoids are involved in the protective adaptive responses of P. bifolia, not only ensuring the survival of this orchid but also contributing to the implementation of its ontogenetic program

The paper presents the results of a study of the anatomical and morphological parameters of Pinus sylvestris L. growing in a serpentinite quarry in the Middle Urals. Morphological and anatomical changes have been identified,that are adaptive in nature and contribute to the survival of the species in extreme environmental conditions. P. sylvestrisunder open pit mining conditions shows a significant decrease in morphometric parameters, such as tree height and annual growth of the trunk. Under the influence of unfavorable factors (lack of mineral nutrients, lack of water, high rockiness of the substrate), the length and diameter of the needles decreased. Of the anatomical features, it is important to notea decrease in the number of resin passages with an increase in their diameter, a decrease in the diameter of the central cylinder and the area of the mesoderm.