Conditions of the urban environment have a significant impact on the ecology of animals, including helminth communities. The response of the helminth community to ecological imbalance and their adaptation to life in the urban environment remain an urgent problem in parasitology. In this study, we aimed to compare the species diversity and distribution of helminths in urban forest parks with varying degrees of anthropogenic pressure. In urbanized territories of 5 locations of the city of Moscow, the infestation parameters of model rodent species were assessed in comparison with a natural, slightly disturbed territory (the scientific and experimental base “Chernogolovka”). In the four most common rodent species (n = 158), Apodemus agrarius, Sylvaemus uralensis, Microtus arvalis, and Clethrionomys glareolus, caught by Hero's traps, the gastrointestinal tract was removed, the number and species of parasites were determined, and the infestation was assessed by 3 parameters. The species composition of helminths and the presence of three parasite classes in the composition of the helminth fauna of the studied species expectedly corresponded to the characteristics of disturbed areas. In addition, a change in the dominant helminth species (H. polygyrus to H. Spumosa) was noted, which indicated a significant influence of the helminth fauna of synanthropic species on the composition of the parasite communities of wild species living in the city. Our study contributes to the accumulation of information on the species composition of endoparasite communities of murine rodents in the city of Moscow, which is important for compiling an up-to-date epidemiological picture of the city.

The range of the polychromous Tulipa suaveolens Roth comprises almost the whole Ponto-Caspian Steppe, from the south-east of Ukraine to western Kazakhstan. High variation in flower color is a unique feature of this species, but features of its geographical distribution remain unclear. We studied T. suaveolens tepal color variation in 56 natural populations across the European range. Tepal colors were detected from digital images using the Lab color model with two chromatic components, a (red color intensity) and b (yellow color intensity). A conclusion was made that, throughout the European range, an obvious T. suaveolens flower color gradient is expressed in the direction from the south-west to the north-east, along which the red chromatic component intensity decreases. A similar gradient is observed when the height above mean sea level increases. The chromatic component a was shown to have a spatial autocorrelation and to depend on the long-term bioclimatic environmental parameters, temperature and precipitation. Thus, the identified geographical trends in the T. suaveolens flower color distribution across the studied part of its range are a consequence of natural selection caused by these two abiotic factors. 

The results of our eight-year study of a population of the rare orchid Dactylorhiza incarnata subsp. cruenta at the northern limit of its range (the Komi Republic) are presented. Weather factors (air temperature and precipitations) were revealed to influence features of the small and big life cycles of this species. The number of plants in the studied population was influenced by the weather conditions of the previous growing season, positively by the temperature in August and negatively by frosts in October. The number of generative (flowering) plants had a positive correlation with the air temperature in July of the previous vegetative season. The fruit set was high (71.2%) and negatively associated with precipitation during flowering of this species. The seed number per fruit in the studied population (9,831 pcs on average) was higher than that in the more southern parts of the range of this species. This indicator, as well as the real seed productivity of the species, is positively related to the level of moisture availability of the current growing season. The seed production is high, from 34 thousand to 154.6 thousand seeds per 1 m2 in several study years, it is positively associated with the sum of active temperatures of the previous growing season. The presence of juvenile individuals (10.0–31.7%) over all study years indicates a successful seed reproduction in this population.

The influence of the major components of plant root exudates, namely, carboxylic acids (succinic acid as an example) and secondary plant phenolic metabolites – flavonoids (rutin as an example), on the microbial degradation of the three-ring polycyclic aromatic hydrocarbon (PAH) phenanthrene by rhizobacterium Mycolicibacterium gilvum was studied. The destructive activity of this microorganism relative to PAH was studied by cultivating it in a liquid mineral medium containing phenanthrene (0.2 g/L), succinic acid (5 g/L), and rutin (0, 0.05, 0.1 or 0.2 mmol/L) at 30°C under aeration on a shaker (130 rpm) for 14 days. The stimulating effect of succinic acid and rutin on the microbial degradation of phenanthrene was revealed. It was found that carboxylate was utilized as the main growth substrate for the microorganism, while flavonol and PAH had little effect on bacterial growth. Rutin had no antimicrobial effect on the microorganisms studied; on the contrary, in combination with succinic acid, it significantly increased the biomass growth. At high concentrations (0.1 and 0.2 mmol/L), rutin inhibited the degradation of phenanthrene by 22 and 56%, respectively. However, at a concentration of 0.05 mmol/L rutin increased phenanthrene degradation by 10%. Thus, the results obtained showed the dependence of the PAH microbial degradation efficiency on the presence, combination, and concentration of the plant root exudate constituents.

Bioremediation is a promising approach for treating oil-contaminated environments. The main objective of this study was to isolate bacteria capable of degrading hydrocarbons for application in oily wastewater treatment from oil-contaminated sites in Hanoi, Vietnam. The bacterial consortium studied was obtained from an oil-contaminated muddy soil sample enriched with crude oil mixed with diesel oil as a carbon source. The reconstituted consortium was able to degrade 93% of the oil content after 7 days of testing. A total of five pure bacterial strains were isolated on TSA agar from the complex microbial communities and were selected as potential candidates for oily sludge biodegradation processes. These isolates were identified based on their morphological and biochemical characteristics. By using molecular biology techniques, five hydrocarbons degrading bacteria were investigated and identified as Pseudomonas mendocina strain MD1 (OL687411.1), Pseudomonas hydrolytica strain MD2 (OL771695.1), Brucella intermedia strain MD3 (OL687412.1), Pseudomonas stutzeri strain MD4 (OL687413.1), and Stenotrophomonas nitritireducens strain MD5 (OL687414.1). The morphological and biochemical characterization of these bacteria showed that five of them were Gram-negative, rod-shaped, catalase positive, the ideal pH was neutral, and the optimum growth temperature was 30ºC in a culture medium with a salinity of 0.5%. These strains are capable of producing extracellular enzymes, such as lipase, amylase, cellulase, and protease.

In the course of the conducted studies, main groups of soil microorganisms in the southern chernozem were identified. The resistance of isolates to the action of oil in the concentration range of 15–25%, the possibility of using it as a carbon source, the ability of soil microbiota to biodegradate oil in contaminated soil and the resistance of bacteria to low temperatures, high NaCl concentrations, acid and alkali resistance were established. 15 genera (31 species) of heterotrophic bacteria were isolated from uncontaminated soil samples of the southern chernozem subtype. Our assessment of the abundance dynamics of microorganisms isolated from laboratory contaminated soils showed that as a result of oil exposure, there was a significant decrease in the numbers of microorganisms: by the 180th day of our experiment, 10 bacteria species belonging to 3 genera were isolated, namely: Bacillus, Micrococcus and Serratia. Among the isolated bacteria, resistance to the action of the pollutant at a concentration of 25% was established for B. coagulans, B. mojavensis, B. megaterium, M. luteus, as well as for the museum strain of B. pumilus CM. By cultivating the studied bacterial strains on a carbon-free medium M9 with 15 and 20% oil added, their ability to use petroleum hydrocarbons as the only carbon source was established; however, when the concentration increased to 25%, only M. luteus, B. mojavensis and B. pumilus KM retained this ability. The presence of hydrocarbon-oxidizing bacteria in soil samples contributed to the 42% decrease in the oil mass concentration in 180 days. The most significant decrease in the concentration of petroleum products occurred in the period from the 10th to the 30th day and amounted to 25%, which is probably due to the increase in the numbers of heterotrophic bacteria. The ability to grow at a temperature of +4°C was established for representatives of the genus Bacillus, including the museum strain of B. pumillus CM, 4 strains of bacilli remained viable in an acidic environment (pH 5), 7 strains of bacilli and M. luteus and S. plymuthica remained viable in an alkaline environment (pH 9). The studied bacterial strains were growing on a GRM-agar with a NaCl concentration of 7%, the ability to grow at a NaCl concentration of 15% was preserved only by the museum strain of B. pumillus KM. The obtained results open the prospects for the use of hydrocarbon-oxidizing bacteria with a high adaptive potential as potential oil destructors capable of biodegradation at low temperatures, in conditions of high salinity and in a wide range of pH of the medium.

The paper presents data of ecological Lepidoptera groups in the nests of the sand martin (Riparia riparia (Linnaeus, 1758)) on the Saratov region territory. The material was collected in R. riparia colonies within five districts of the Saratov region in different 2019–2021 seasons. Three clusters were identified for 13 Lepidoptera species belonging to 10 families during our statistical data analysis. One cluster covers typical inhabitants of burrows and is represented by a single species, Infurcitinea rumelicella (Rebel, 1903). Atypical species comprise the remaining two clusters. All the presented species, namely: Acompsia cinerella (Clerck, 1759), Niditinea fuscella (Linnaeus, 1758), Brachmia dimidiella ([Denis & Schiffermüller], 1775), Epermenia ochreomaculella (Milliére, 1854), Caloptilia fidella (Reutti, 1853), Laodamia faecella (Zeller, 1839), Polypogon tentacularia (Linnaeus, 1758), Borkhausenia fuscescens (Haworth, 1828), Acleris forsskaleana (Linnaeus, 1758), Cochylidia implicitana (Wocke, 1856), Loxostege sticticalis (Linnaeus, 1758) are not typical for the nests of the sand martin. Our conducted observations of the species composition showed its being extremely poor relative to representatives of the nest-dwelling fauna, which is associated with the nest inaccessibility of burrowing birds, which R. riparia belongs too. 

Floristic complexes of the Vetlyanka river are characterized by a high pool of rare plants with different protection categories in the Saratov region. There are 6 species in total (Bulbocodium versicolor, Hyacinthella leucophaea, Tulipa gesneriana, Iris pumila, I. halophila, and Scilla siberica). For the first time, these ecotopes were noted for S. siberica, B. versicolor, and Iris halophila. At the same time, S. siberica and I. halophila have narrow ecological amplitude. The studied cenopopulations of rare plants in the floristic complexes of the Vetlyanka river are stable in time and space. In the cenopopulations of the studied plants a process of self-renewal proceeds, which is hampered by a number of anthropogenic factors. The ontogenetic spectrum of the B. versicolor coenopopulation is a single-vertex spectrum with a high proportion of individuals of the generative fraction (70.2%). The age spectrum of the S. siberica cenopopulation is dominated by pregenerative plants – 67.4% of the total number of analyzed individuals with a maximum of immature individuals (46.5%). The high proportion of pregenerative plants (52.5%) in the coenopopulation of T. gesneriana indicates its ability to self-renewal and is characterized by a bimodal age spectrum. The coenopopulations of the studied species according to T. A. Rabotnov’s classification are normal incomplete.