Land-Use Change in New Moscow: First Outcomes after Five Years of Urbanization

Urbanization coincides with remarkable environmental changes, including conversion of natural landscapes into urban. Moscow megapolis is among the largest urbanized areas in Europe. An ambitious New Moscow project expanded the megapolis on extra 1500 km2 of former fallow lands, croplands and forests. The research aimed to monitor land use changes in New Moscow between 1989 and 2016 years. Landsat 5 and Landsat 8 images (30 m spectral resolution) and Sentinel – 2 images (10 m spectral resolution) were analyzed. All the images were collected for the similar summer period (from June to August). The images were preprocessed and classified by Semi-Automatic Classification Plugin in open source QGIS software to derive land cover maps. The following land cover classes were identified: water, built-up areas, bare soils, croplands and forested areas, and the total area covered by each class was estimated. The following land-use change pathways were reported: 1) reduction of the forested areas by 2.5% (almost 2000 ha) between 1989 and 1998; 2) partial reforestation (more than 1000 ha) and abandonment of croplands (more than 3000 ha) between 1998 and 2010 and 3) intensive urbanization (more than 11000 ha) between 2010 and 2016. New build-up areas and infrastructures were constructed on former forested areas and croplands. Although, some uncertainties in the absolute estimates are expected due to the classification errors, the general urbanization trend can be clearly distinguished as a principal outcome after the five years of New Moscow project

Smart and Sustainable Cities: From Environmental Threats Towards Nature Based Solutions and Sustainable Management

Sustainable urban development has become an increasingly important topic in scientific and political agendas. “Smart and Sustainable Cities - 2018” continues the series of conferences, organized by RUDN University under the umbrella of Jean Monnet Project EDEMS, to discuss environmental, technological and socio-economical challenges and perspectives of sustainable urban development

Preface

Purpose: Journal of Soils and Sediments publishes the main outcomes of SUITMA 9 Conference in its Special Issue. SUITMA (Soils of Urban, Industrial, Traffic, Mining and Military Areas) working group organizes conferences biannually all over the world. The ninth conference organized in Moscow in May 2017 involved more than 215 speakers from 25 countries, whose presentations focused on challenges and opportunities of urbanization for soil functions and ecosystem services. Materials and methods: The main outcomes of SUITMA 9 were analyzed in comparison to the previous SUIMTA conferences and the main topics were distinguished. Manuscripts accepted for publishing in the Special Issue were reviewed and presented. Results and discussion: Comparison of the topics highlighted in different special issues highlighted the evolution of the SUITMA studies from fundamental morphological descriptions and classifications to applied studies on soil engineering, assessment of SUITMA functions and ecosystem services. Conclusions: The manuscripts accepted to the Special Issue covered included various case studies of SUITMA ecosystem services (e.g. global and local climate regulation, biodiversity maintenance and improvement, nutrients balance and recreation) and disservices (e.g. pollution by heavy metals, polycyclic aromatic hydrocarbons and sulfur). The increasing role of SUITMA studies for urban management and decision making was concluded

Urbanization affects soil microbiome profile distribution in the russian arctic region

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

Technosols on mining wastes in the subarctic: Efficiency of remediation under Cu-Ni atmospheric pollution

The copper-nickel factory's emissions in the Murmansk region, Russia, led to the degradation of plant cover and topsoil with the subsequent formation of industrial barrens. In this study, the industrial barrens were remediated by means of Technosol engineering, when grasses were sown on the two different types of mining wastes (carbonatite and serpentinite-magnesite) covered by hydroponic vermiculite. The serpentinite-magnesite waste was significantly different from the carbonatite waste in the content of silicon (Si) and manganese (Mn), pH, and texture. Both wastes had an alkaline pH level and high content of calcium (Ca) and magnesium (Mg). The vegetation and Technosol properties at the remediated sites were analyzed in 2017 and compared to the initial state (2010 year) to assess the efficiency of the long-term remediation. The quality and sustainability of Technosols based on the serpentinite-magnesite wastes were substantially higher compared to the carbonatite-based Technosol. Biomass and a projective cover of the grass community depended on Si content in the original mining waste and were found to be higher in the serpentinite-magnesite Technosol. The content of organic carbon and its fractions, microbial biomass and basal respiration after seven years of Technosol evolution was comparable to natural values. These parameters were directly related to plant cover state and were inversely proportional to copper (Cu) content in Technosol. The Technosol development led to the reduction of nickel (Ni) and Cu migration in soil-plant ecosystems due to neutralization and adsorption properties of mining wastes and phytostabilization by underground parts of grass communities. The Technosol development in its early stage of pedogenesis indicates the efficiency of applied remediation technology to the degraded acidic soil under the conditions of industrial atmospheric pollution

Organic matter accumulation by alkaline-constructed soils in heavily metal-polluted area of Subarctic zone

Purpose: The research aimed to investigate properties and functions of soils constructed from alkaline mining wastes of different origin to remediate the industrial barren resulted from long-term emissions of the copper-nickel factory in the Subarctic region (Kola Peninsula, Russia). Conventional indicators of the remediation effectiveness (pH and metal content in geochemical fractions) were related to the indicators of soil functions such as biomass production, accumulation of organic carbon, microbial activity, and soil respiration. Materials and methods: The experimental area included two sites with polluted and degraded Podzol and Histosol soils located in 1.5 and 0.7 km from the nonferrous (Cu-Ni) smelter, respectively. At the sites, artificial soil constructions were made from mining wastes or quarry sand covered by the vermiculite layer with lawn grasses planted on top. Plant biomass was collected every year starting from the experiment set-up. In 5 to 8 years, soil samples were collected on the layer basis, and chemical, biological, and morphological properties were analyzed. Sequential fractionation of metals was conducted using a modified Tessier’s scheme. The microbial biomass and its respiration activity were determined. Micromorphological studies were conducted using an optical microscope. Soil respiration was measured on-site by IRGA with simultaneous observations of soil moisture and temperature. Results: The plant growth and residues' deposition at both experimental sites triggered carbon accumulation and resulted in 2–3 times higher content of organic carbon in the upper constructed soil layer compared to the initial content in mining wastes. Carbon accumulation was a key driver for the development of soil microbial communities and had a positive effect on the metal immobilization. This effect was strengthened by high pH inherited from the alkaline wastes and resulted in the performance of constructed soils as geochemical barriers. In their upper layers, where the root biomass was the highest, about 30–60% of Cu and Ni were bound by organic matter. In the underlying polluted soil, the most toxic water-soluble metal fraction was completely neutralized; and the metal concentrations in exchangeable fraction decreased by a factor of four improving the habitat conditions of the microbiome. Organic matter accumulation by clay material with the formation of organo-mineral films was found in the vermiculite-lizardite variant. Conclusion: Soil constructions made from alkaline mining wastes in the Subarctic supported the development of plant and microbial communities, organic matter accumulation, and metal immobilization. This technology allows protecting the environment from further pollution under the continuous emissions of the copper-nickel factory

Secondary soil salinization in urban lawns: Microbial functioning, vegetation state, and implications for carbon balance

Deicing agents cause soil salinization and degradation in urban areas. We assessed the capacity of urban lawns to maintain carbon sequestration and nutrient cycling with increasing soil salinity. The sensitivity to soil salinity of the main ecosystem players: plants and microorganisms were assessed considering their complex interactions between each other and environment. The effects of low and moderate soil salinization by common deicing agent (NaCl) were evaluated in mesocosms planted with two urban lawns: Lolium perenne and mixture of grasses. Mesocosm-, plant-, and soil-level gas exchange were assessed on a short-term (days) and long-term (months) scales. Microbial response was characterized by analyzing the microbial properties and activities of nine enzymes. Carbon balance remained independent on the salinity due to cancelling effect of lowered gross primary production (GPP, −20%), decreased C input by plants into the soil (−40% for mixture) balanced by slower microbial decomposition of organic matter (−20%) and so, lower soil respiration (−35%). GPP declined as a long-term response by a combination of stomatal constraint on photosynthesis with leaf respiration increase. Toxic effects of salinization on soil respiration were observed only for temperatures above 15°C. Microbial community with high C:N ratio (common for fungi) was the most sensitive to salinization. The death of microbial biomass (−31% for Lolium) and cell lysis increased soil enzyme activities (+38% for Lolium). We conclude that C balance of urban lawns remain homeostatic at secondary salinization. Temperature effects and plant-microbial interactions will determine C and nutrients cycling under salinity stress in urban lawns.s

Microscopic fungi in big cities : Biodiversity, source, and relation to pollution by potentially toxic metals

For the first time, a mycological analysis of outdoor urban environment (air, leaves, sealed surfaces) was carried in the cities of subarctic (Murmansk) and temperate (Moscow) climatic zones. The chemical composition of dust deposited on leaves of dominant tree species was taken as an indicator of the air quality. Assessment of the complex impact of factors (climate zone, type of substrate, anthropogenic load) on the quantitative and qualitative parameters of mycobiome was performed. Compared to Moscow, Murmansk was characterized by an increased number and concentrations of pollutants in the deposited dust. The number of culturable airborne fungi in Murmansk was substantially lower than in Moscow. Half of the species belonged to the opportunistic in both cities. Most dangerous opportunistic fungi were absent in the air of recreational zones but present on leaves surface and in road dust in all assessed zones of the cities. Dust chemical composition affected the diversity of fungi species. While the relationship of biological parameters with concentration of potentially toxic metals was generally negative, Cd increased the fraction of opportunistic fungi in road dust. The study revealed an importance of substrate in determining the sensitivity of outdoor mycobiome to pollution and highlighted its biological characteristics sensitive to climate

Diversity of Microbial Communities, PAHs, and Metals in Road and Leaf Dust of Functional Zones of Moscow and Murmansk

The impact of geographical factors, functional zoning, and biotope type on the diversity of microbial communities and chemical components in the dust of urban ecosystems was studied. Comprehensive analyses of bacterial and fungal communities, polycyclic aromatic hydrocarbons (PAHs), and metals in road and leaf dust in three urban zones of Murmansk and Moscow with contrasting anthropogenic load were conducted. We found that the structure of bacterial communities affected the functional zoning of the city, biotope type, and geographical components. Fungal communities were instead impacted only by biotope type. Our findings revealed that the structure of fungal communities was mostly impacted by PAHs whereas bacterial communities were sensitive to metals. Bacteria of the genus Sphingomonas in road and leaf dust as indicators of the ecological state of the urban ecosystems were proposed

Phylloplane Biodiversity and Activity in the City at Different Distances from the Traffic Pollution Source

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 considered as an additional tool for bioindication