Dynamically developing urbanization causes a number of environmental effects, including those related to the chemical transformation of soils. Relatively less information about the urban areas of the Arctic and Subarctic zones, constructed mostly on permafrost and intensively populated areas can be found. By the example of the analysis of basic soil properties and concentrations of trace metals in the soils of the cities of Salekhard, Urengoy, Nadym, Novy Urengoy and Gaz Sale (the Yamalo-Nenets Autonomous District), as well as various functional zones within the cities, the relationship between the age of the cities, the level of anthropogenic pressure and the type of parent materials and the character of accumulation of metals in the soil profile of urban soils have been described. The direct correlation was found between the content of Pb, Cr, Ni, As and soil sorption characteristics. In young cities built on sandy sediments, there is less accumulation of heavy metals in the topsoil horizons. Relatively higher concentrations of Cu and Cd were noted in soils of industrialized cities, regardless of functional zones. The higher content of Cr, Ni, Cu, Zn, As and Pb has been registered in older zones also frequently used for residential purposes. The calculated values of the PI index for some functional zones of young cities show the medium and high content of heavy metals. The analysis of Igeo and PLI indices shows a large diversity both in relation to individual cities and their functional zones. Soil quality, in spite of the high level of anthropogenic load, was assessed as mostly satisfactory.

The aim of the study was to determine electrical resistivity peculiarities of tundra and forest tundra soils and soil-permafrost layers of the Yamal region. Measurements of electrical resistivity of soil and permafrost strata were performed with a portable device LandMapper (to a depth of 300-500 cm). These measurements allow determination of the values of apparent electrical resistivity of soils and permafrost at different depths and determination of the depths of the permafrost table on each key plot. It was found that there are several trends in vertical distribution of apparent electrical resistivity values. The first trend is a monotonous increase in electrical resistivity values to the depth. It may be explained by the increasing electrical resistivity within the soil depth in relation to the increase in permafrost density. The second trend is a sharp decrease replaced by a gradual increase in electrical resistivity values caused by changing of non-frozen friable debris to frozen massive crystalline rock. These differences were related to the type of landscape: flat lowlands composed of friable grounds underlain by permafrost or friable grounds with permafrost underlain by a rock crystalline layer.

Soil salinization is an up-to-date worldwide issue. This problem is especially urgent in the territories of arid and semi-arid regions. The aim of this work was to analyze the relationships between the level of soil salinity and the key spectral indices obtained on the base on Sentinel-2A satellite data. The study has been conducted on an area of 5127 ha in the Trans-Ural steppe zone (Republic of Bashkortostan, Russia). Vegetation index NDVI and 15 salinity indices have been used to analyze the relationships. The salinity index III (G×R)/B using quadratic statistical relation showed the best correlation values with salinity level (R=0.89, R2=0.79). In general, it was found that the highest correlation values are observed with indices based on the three channels of visible range: salinity index 2 √(G×R) (R=0.82, R2=0.67), salinity index 4 √(G2+R2) (R=0.82, R2=0.67), salinity index VII (G+R)/2 (R=0.82, R2=0.67). The vegetation index NDVI showed the absence of a correlation with the values (R=-0.10, R2=0.01), due to weak development or dry state of vegetation. The areas of saline soils using salinity index III were calculated. The methods elaborated could be useful for mapping and accounting of saline soils based on satellite data under environmental conditions similar to this study.

This study investigates the effects of climate change on streamflow in the Ayazma river basin located in the Marmara region of Turkey using a hydrological model. Regional Climate Model (RCM) outputs from CNRM-CM5/RCA4, EC-EARTH/RACMO22E and NorESM1-M/HIRHAM5 with the RCP4.5 and RCP8.5 emission scenarios were utilized to drive the HBV-Light (Hydrologiska Byråns Vattenbalansavdelning) hydrological model. A trend analysis was performed with the Mann–Kendall trend test for precipitation and temperature projections. A meteorological drought assessment was presented using the Standardized Precipitation–Evapotranspiration Index (SPEI) method for the worst-case scenario (i.e., RCP8.5). The calibrated and validated hydrological model was used for streamflow simulations in the basin for the period 2022–2100. The selected climate models were found to produce high precipitation projections with positive anomalies ranging from 22 to 227 mm. The increase in annual mean temperatures reached up to 1.8 °C and 2.6 °C for the RCP4.5 and RCP8.5 scenarios, respectively. The trend results showed statistically insignificant upward and downward trends in precipitation and statistically significant upward trends in temperatures at 5% significance level for both RCP scenarios. It was shown that there is a significant increase in drought intensities and durations for SPEI greater than 6 months after mid- century. Streamflow simulations showed decreasing trends for both RCP scenarios due to upward trend in temperature and, hence, evapotranspiration. Streamflow peaks obtained with the RCP8.5 scenario were generally lower than those obtained with the RCP4.5 scenario. The mean values of the streamflow simulations from the CNRM-CM5/RCA4 and NorESM1-M/HIRHAM5 outputs were approximately 2 to 10% lower than the observation mean. On the other hand, the average value obtained from the EC-EARTH/RACMO 22E outputs was significantly higher than the observation average, up to 32%. The results of this study can be useful for evaluating the impact of climate change on streamflow and developing sustainable climate adaptation options in the Ayazma river basin.