The definition of recreational sustainability in bogs is becoming an urgent task in Russia as a result of ecological tourism developed in Protected Areas. In this study, we assessed the impact of recreational nature management on wetland plant communities of the Plavnitskoye Boloto ecological path in the Polistovsky State Nature Reserve solving the following tasks: 1) to determine the threshold of permissible anthropogenic impact on wetland sites with different types of plant communities; 2) to evaluate the recovery of vegetation cover; 3) to determine the relative tolerance of bog plant communities to trampling. Modelling of the direct anthropogenic impact on bog plant communities with different load values has made it possible to assess the damage on the vegetation cover visually and to reveal their resistance and ability to subsequent recover. We demonstrated that the Phragmites-Sphagnum community (Phragmites australis + Eriophorum vaginatum - Sphagnum fallax + Sphagnum angustifolium) was the least resistant to trampling, while the shrub-Carex-Sphagnum plant community (Chamaedaphne calyculata + Oxycoccus palustris + Menyanthes trifoliata + Eriophorum vaginatum - Sphagnum fallax) was the most resistant. After the removal of anthropogenic load on the studied sites, the damaged vegetation cover recovered to different degrees. In the first year, the plant communities of the shrub-Carex-Sphagnum bog had the fastest recovery, where relatively hygrophilous species of Sphagnum mosses predominate under mesotrophic conditions and a higher level of groundwater. The Eriophorum-Sphagnum community (Pinus sylvestris (f. willkomii) - Andromeda polifolia + Oxycoccus palustris + Eriophorum vaginatum + Rhynchospora alba - Sphagnum magellanicum) had the best long-term resilience for three years, and, as a result, it turned out to be the most tolerant to trampling. In some parts of the Phragmites-Sphagnum mesotrophic bog, the original plant community did not recover after three study years. Thus, this type of bog is the most vulnerable to recreational impact.
The history of the co-existence of the human - grey wolf (Canis lupus) is an example of competition, close interaction during domestication, persecution, and extermination. The amazing plasticity and adaptations of the grey wolf ensured the sustainable survival of its populations. Being at the top of the food pyramid, Canis lupus is a consumer of the highest order. It actively regulates the abundance of its main prey, i.e. large ungulates, through their selective predation. These circumstances highlight the interest to study this carnivore species inhabiting the center of European Russia. Using craniometric methods, we studied 326 wolf skulls obtained in the Tver region, Smolensk region, Yaroslavl region, and Vologda region. We revealed a high intraspecific size polymorphism, based on the analysis of the spatial and temporal dynamics of the craniometric characters of the grey wolf collected in the center of European Russia. These data are originated from an area of 350 × 450 km over a 65-year period. The spatial and temporal dynamics were demonstrated for measurements characterizing the length of the skull, the length of the upper and lower jaw, and odontological features characterizing the size of the crown of the first premolar and second molar teeth. The sexual variation of the grey wolf skull is characterized by a generally smaller size of female skulls (3.6% on average). A feature related to the functioning of the jaw apparatus, the width of the articular head of the mandible, showed the highest sexual variation (8.1%-difference between males and females). In order of increasing influence, the polymorphism factors are arranged as follows: chronographic, spatial, sex-related, and age-related. Besides the fundamental reasons caused by the sexual selection, the sexual dimorphism in size is determined by exogenous factors associated with a certain degree of segregation in trophic niches of males and females, their different social role, determined by the species life strategy. The geographic variability of the grey wolf skull has a complex and disordered nature. It is primarily caused by the social organization and strong territoriality of the grey wolf, limiting the panmixia, as well as by the stochastic intrapopulation processes due to a generally high elimination of individuals in populations. In the study area, the obtained spatial and temporal grey wolf variability could be caused by the complementary influence of a number of factors. The nature of the variability in the size of the grey wolf skull makes it possible to associate it with the dynamic parameters of the trophic ecology of the studied species, depending on the population-demographic characters of the main prey of the grey wolf, Alces alces and Sus scrofa, in the study area. In addition, it is not excluded that the temporal variability is affected by stochastic factors caused by the intensive grey wolf elimination as a result of sum death, active emigration, and immigration of animals caused by the anthropogenic load. By contributing to an intrapopulation polymorphism increase, the morphological heterogeneity of the grey wolf population increases the adaptive population ability, which ultimately favors the survival of this carnivore species.