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The microbiological parameters of technosols based on peat-sand mixtures, made in cities of different bioclimatic zones: Apatity (subarctic), Moscow (temperate humid), Rostov-on-Don (temperate dry), were determined for the first time. Such properties as microbial biomass, activity and specific respiration of technosols were evaluated by the technics of substrate-induced and basal respiration, as well as the physiological profile and functional diversity of soil microbial communities by the MicroResp technic. Fungal biomass was assessed using light luminescence microscopy. In technosols from different climatic zones, microbial biomass carbon and microbial activity (basal respiration) values were found to be lower compared to natural (background) reference soils. Fourteen months after the beginning of the experiment, the microbial biomass in Moscow and Rostov-on-Don decreased by around 1.5 and 2 times, respectively, compared to background soils, whereas in Apatity, on the opposite, it increased. Microbial respiration in the conditions of the north increased by 1.2 times, while in temperate climate it decreased by 1.2 (Moscow) and 3.4 times (Rostov-on-Don). The specific respiration (microbial metabolic quotient) qCO2 was found to be sufficiently high (3.5–4.5 CO2-C µg-1 Cmic h−1) for the first two years of the study for all experimental stations. Alterations in the microbial community physiological profile of technosols in different bioclimatic zones were discovered, most noticeably demonstrated in Moscow. In terms of fungal biomass, the technosols of Rostov-on-Don are closest to the background soil, while in Moscow it is lower by 2 times and almost 3.5 times in Apatity. After 14 months in the technosols, created in temperate humid and temperate dry conditions, tended to change the functional diversity of microbial communities towards natural reference. Under northern conditions, the physiological profile of the microbial community changed insignificantly. Alterations

The phylloplane is an integrated part of green infrastructure which interacts with plant health. Taxonomic characterization of the phylloplane with the aim to link it to ecosystem functioning under anthropogenic pressure is not sufficient because only active microorganisms drive biochemical processes. Activity of the phylloplane remains largely overlooked. We aimed to study the interactions among the biological characteristics of the phylloplane: taxonomic diversity, functional diversity and activity, and the pollution grade. Leaves of Betula pendula were sampled in Moscow at increasing distances from the road. For determination of phylloplane activity and functional diversity, a MicroResp tool was utilized. Taxonomic diversity of the phylloplane was assessed with a combination of microorganism cultivation and molecular techniques. Increase of anthropogenic load resulted in higher microbial respiration and lower DNA amount, which could be viewed as relative inefficiency of phylloplane functioning in comparison to less contaminated areas. Taxonomic diversity declined with road vicinity, similar to the functional diversity pattern. The content of Zn in leaf dust better explained the variation in phylloplane activity and the amount of DNA. Functional diversity was linked to variation in nutrient content. The fraction of pathogenic fungi of the phylloplane was not correlated with any of the studied elements, while it was significantly high at the roadsides. The bacterial classes Gammaproteobacteria and Cytophagia, as well as the Dothideomycetes class of fungi, are exposed to the maximal effect of distance from the highway. This study demonstrated the sensitivity of the phylloplane to road vicinity, which combines the effects of contaminants (mainly Zn according to this study) and potential stressful air microclimatic conditions (e.g., low relative air humidity, high temperature, and UV level). Microbial activity and taxonomic diversity of the phylloplane could be consid

Urbanization in the Arctic results in considerable and still poorly known environmental consequences. The effect of urbanization on soil microbiome—an ecosystem component highly sensi-tive to anthropogenic disturbance—remains overlooked for the Arctic region. The research compared chemical and microbial properties of the natural Podzol soils and urban soils of Murmansk—the largest Arctic city. Particular attention was given to the profile distribution, which is almost com-pletely ignored by most microbial studies. Soil microbiome was investigated by the quantitative indicators based on fluorescence microscopy (microbial biomass) and PCR real-time methods (amount of rRNA genes copies of archaea, bacteria, and fungi). The principal changes in urban soils’ properties compared to the natural references included a shift in pH and an increase in C and nutrients’ contents, especially remarkable for the subsoil. The numbers of rRNA genes copies of archaea, bacteria, and fungi in urban topsoils (106 –1010, 109 –1010, and 107 –109, respectively) were lower than in Podzol; however, the opposite pattern was shown for the subsoil. Similarly, the total microbial biomass in urban topsoils (0.55–0.75 mg g−1 ) was lower compared to the 1.02 mg g−1 in Podzols, while urban subsoil microbial biomass was 2–2.5 times higher than in the natural conditions. Both for urban and natural soils and throughout the profiles, fungi were dominated by mycelium forms; however, the ratios of mycelium–spores were lower, and the amount of thin mycelium was higher in urban soils than in natural Podzols. Urbanization in the Arctic altered soil morphological and chemical properties and created a new niche for microbial development in urban subsoils; its contribution to biodiversity and nutrient cycling promises to become increasingly important under projected climate change.