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The existing classifications of soil texture are based on the sedimentation data. The aim of this article is to consider the ways to develop soil textural classification on the basis of particle-size distribution (PSD) data obtained by the laser diffraction method. A detailed comparison of PSD data obtained by the classical pipette method and the method of laser diffractometry has been performed. We have shown the reproducibility of the laser diffraction method and the effect of the oxidation stage on the soil texture class. This study is based on eight genetic soil types (overall, 32 full-profile soil pits) forming a zonal soil sequence from Podzols (Subpolar Urals) to ferrallitic soil (southwest Oceania) and differing in their mineralogical compositions, textures, and elementary pedogenetic processes. The direct use of the Kachinskii and USDA classifications with the data of the laser diffraction method leads to mistakes in determining the soil texture class in 43 and 65% of cases, respectively. The increasing complexity of recalculation, introduction of new variables, and accounting for interlaboratory errors allow us to determine correctly the texture class according to the Kachinskii and USDA classifications in no more than 70 and 72% of soil samples, respectively. The most simple and effective approach to solve the classification problem for the laser diffraction method is to calibrate existing classifications directly on the basis of data on soil samples, for which the texture class was determined by the field method.

We have carried out a field experiment to study the migration of Ni, Cu, and Co from the organic horizon of Al–Fe-humus podzols polluted with heavy metals (HMs) to the dominant species of dwarf shrubs, mosses, and lichens forming the ground vegetation layer in middle-aged pine forests. The following hypotheses were tested: (1) the introduction of metallurgical dust causes destruction of ground vegetation layer even in the absence of sulfur dioxide; (2) the destruction of this layer is caused by high concentrations of HMs in the aboveground organs of plants and lichens, which lead to their death; and (3) the level of HM accumulation by different taxa is directly correlated with their strategy of mineral nutrition. The contents of Ni, Cu, and Co in the organic horizon of podzols and in the assimilatory organs of dominant dwarf shrub, moss, and lichen species were determined by atomic absorption spectrometry. High inter- and intracenotic variation in the level of HM pollution of the soil organic horizon was revealed, which caused spatially uneven destruction of the ground vegetation layer. The translocation of HMs from the polluted soil to the aboveground parts of plants and lichens leads to a 1.5- to 5-fold increase in the content of HMs in all species, which does not exceed the toxicity threshold and does not prevent their growth in the experimental plots. The introduction of metallurgical dust over 5 years made the level of pollution of the organic soil horizon comparable to that in the buffer zone of the Severonikel Plant. This made it possible to compare the HM content in plants and lichens under the conditions of soil and aerotechnogenic pollution and determine the features of HM accumulation by organisms with different strategies of mineral nutrition. The Ni < Cu concentration ratio in the organic soil horizon is reversed in the leaves of dwarf shrubs and green and brown parts of moss Pleurozium schreberi under conditions of either soil pollution and aerotechnogenic pollution.

Materials of engineering-ecological researches on various economic objects in Udmurtia are processed and systematized. Average (background) concentration of the heavy metals which are subject to obligatory control at engineering-ecological researches (lead, cadmium, zinc, copper, nickel, arsenic, mercury) for the main associations of soils and most wide-distributed kinds of soils are defined. It is revealed that with decreasing the soil’s podzol content and increasing the soil’s clay content, concentrations of heavy metals naturally raise. In general, similar soils are characterized by similar concentrations of heavy metals and similar ratios of concentration. It is established that excesses of hygienic standards on such elements as nickel, arsenic and to a lesser extent zinc, copper and cadmium, are not only something exclusive in Udmurtia, but also spreading more and more widely, especially in soils of light structure. The received average concentration can be accepted as background one at the subsequent engineering-ecological researches in the region.

The extent of microbiological processes in soil is determined not only by the number of microorganisms, but mainly by their activity. Therefore, it is extremely relevant to study the influence of various organic, mineral fertilizers, lime used for the cultivation of gley-podzolic soils of the Far North, on the change of intensity and development of the most important microbiological processes in these soils. In its natural state, soils are a multi-component system consisting of many heterogeneous microenvironments inhabited by microorganisms with different food chains. In anthropogenic activities, and in particular, in the introduction of organic and mineral fertilizers, the environmental conditions in soils change significantly, leading to a significant adjustment in taxonomic structure of microbial cenoses and their functional activities. Particularities of soil-climatic conditions also significantly affect species composition and features of functioning of microbocenoses in soils. Therefore, when choosing the most effective methods of soil cultivation in each particular climate zone, a lot of attention is paid to their biological assessment. The studies show that fertilizer and lime has a positive effect on the prokaryote complex of soil microorganisms of everfrozen soils. Keywords: Everfrozen soils; Fertilizers; Peat; Manure; Lime; Bacteria; Fungi; Soil enzymes References Arinushkina E.V. (1970). Manual for the chemical analysis of soils. Moscow: Publishing house Mosk. University, 487 p. Babeva I.P., Chernov I.Yu. (1982). Yeast in the tundra soils of Taimyr. Soil Science. No. 10, pp. 60-64. Great Workshop on Microbiology (1962). Ed. G. L. Seliber. M. Higher school. 492p. Bunnell F.I., Miller A.K, Flanagan P.W & Bennoit K.F. (1980). The microflora: composition, biomass and environmental relation. An arctic ecosystem: (The coastal tundra at Barrow, Alaska) Ed.J. Brounet al. - Stroudsburg (Pennsylvania), pp: 255-290. Voznyakovskaya Yu.M., Kulikova A.S. (1955). Microflora accompanying mycorrhiza. Tr. conf. on plant mycotrophy. Ed. Academy of Sciences of the USSR. M, pp:123-134. Vyblov N.F. (1979). The influence of fertilizers on the microflora of gray forest soils in Gorny Altai. Microbial associations and their functioning in the soils of Western Siberia.Novosibirsk, pp:178-183. Geller I.A., Yuspe F.B. (1954). On the influence of mineral fertilizers on the microbiological processes of the soil. Microbiology, 23(4), 451-453. Goloborodko S.P., Iutinskaya G.A. (1978).Influence of irrigation and intensive fertilization of a cultivated pasture on its productivity and the number of microorganisms in the conditions of the south of the Ukrainian SSR. Dokl. TSKHA, 239 , pp:121-124. Evdokimova G.A., Mozgova N.P. (2001). Microorganisms of tundra and forest podzols of the Kola North. Ed. KSC RAS, Apatity, 184p. Zvyagintsev D.G., Babieva I.P. & Zenova G.M. (2005). Biology of soils. Moscow: Publishing house of Moscow State University, 448 p. 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Microorganisms and agricultural productivity. M, 343 p. Mishustin, E.N. (1975). Association of soil microorganisms. M, Science. Pp. 114-120. Pectolytic enzymes of microorganisms. (1971). V.I.Smirnov, V.V. Kotelev. Academy of Sciences of the MSSR. Dept. microbiology. Chisinau, 35 p. Polyanskaya L.M., Lukin S.M. & Zvyagintsev D.G. (1997) Changes in the composition of microbial biomass in soil during cultivation Pochvovedenie. 2, 206-212. Polyanskaya L.M., Golovchenko A.V. & Zvyagintsev D.G. (1998) Determination of the viability of spores and mycelium of fungi in the soil. Microbiology. 67(6), 832-836. Polyanskaya L.M., R.B. Gorodnichev, & D.G. Zvyagintsev (2013). Sizes of bacteria cells in soils, determined by the method of "cascade" filtration. Izvestia RAN. Biological series. 2, p. 14. DOI: 10.7868 / S00023329130101284–151 Stepanova L.N. (1959). Influence of long-term use of mineral fertilizers on the content of toxic bacteria in sod-podzolic soils. // Scientific. doc. higher. schools. Biol. Science. 3, 243-247. Chunderova A.I. (1973). Enzymatic activity of soddy-podzolic soils of the North-West zone: abstract of Ph.D. dis. Dr. Biol. sciences . Tallinn. 46 p.

A combined analysis of the current climate trends and the dynamics of soil respiration under soddy–weakly podzolic sandy-loamy soil (Entic Podzol (Arenic)) in the forest and meadow cenoses in the Prioksko-Terrasny Biosphere Reserve (southern part of the Moscow oblast) is performed. During the observation period (1998–2018), distinct trends of an increase in the average annual air temperature (Tair) and aridity of the summer season as well as a decrease in the duration of stable snow cover are observed. A general trend of a decrease in the total CO2 fluxes from the Entic Podzol (Arenic) under a forest and a meadow for all seasons of the year and throughout the year is also observable on this background. The linear trends of a decrease in the annual and fall seasonal CO2 fluxes from the soils in both cenoses are statistically significant (P < 0.05). Over the 21-year observation period, the monthly average CO2 fluxes from soils have tightly correlated with the average monthly Tair (r = 0.78–0.84, P < 0.001). In dry years, the temperature sensitivity of soils expressed via the Q10 coefficient is by 10–12% lower, than in the years with normal moistening. The average long-term values of annual soil respiration (AnSR) in the forest and meadow cenoses amount to 581 ± 54 and 727 ± 71 g C/(m2 year), respectively, with an interannual variation of 20–22%. The AnSR and summer hydrothermal coefficient are the most closely related explaining 51–56% of the variance in annual CO2 fluxes from soils. The warm season (May–October), which coincides with the period of active plant vegetation, accounts for 73–77% of the AnSR. However, the share of the cold season (November–April) in the annual CO2 flux from soils may reach 38–39% in individual years. Expansion of the network of stationary long-term year-round monitoring of soil respiration is a necessary condition for obtaining both more realistic estimates of the CO2 fluxes from soils and predictions of the ecosystem responses to the current and future climate changes.

Background: There is considerable uncertainty about the actual size of the global soil organiccarbon (SOC) pool and its spatial distribution due to insufficient and heterogeneous data cover-age. Aims: We aimed to assess the size of the German agricultural SOC stock and develop a stratification approach that could be used in national greenhouse gas reporting. Methods: Soils from a total of 3104 sites, comprising 2234 croplands, 820 permanent grasslands and 50 sites with permanent crops (vineyards, orchards) were sampled in a grid of 8 x 8 km to a depth of 100 cm in fixed depth increments. In addition, a decade of management data was recorded in a questionnaire completed by farmers. Two different approaches were used to stratify cropland and grassland mineral soils and derive homogeneous groups: stratification via soil type (pedogenesis) and via SOC-relevant soil properties. Results: A total of 146 soils were identified as organic soils, which stored by far the highest average SOC stock of528–201 Mg ha–1 in 0–100 cm depth. Of the mineral soils, croplands and permanent crops stored on average 61–25 and 62–25 Mg ha–1 in 0–30 cm (topsoil) and 35–30 and 44–28 Mg ha–1 in 30–100 cm (subsoil), while permanent grasslands stored significantly more SOC (88–32 and 47–50 Mg ha–1 in topsoil and subsoil). Overall, topsoils stored 67–14% and subsoils 33–14% of total SOC stocks. Soil C:N ratio, clay content and ground-water level were major factors that explained the spatial variability of SOC stocks in mineral soils. Accordingly, Podzols, Gleysols and Vertisols were found to have the highest SOC stocks. Conclusions: Stratification via soil properties yielded the most comparable cropland and grassland strata and is thus preferable for estimating land-use change effects, e.g., for greenhouse gas inventories. In total, 2.5 Pg C are stored in the upper 100 cm of German agricultural soils, making them the largest organic carbon pool in terrestrial ecosystems of Germany. This bares a large responsibility for the agricultural sector and society as a whole to maintain and, if possible, enhance this pool.

The mobility of Cd, Co, Cu, Ni, and Zn in podzols and organic soils (Histosols) in the area of long-term pollution from the Monchegorsk copper–nickel plant (Murmansk oblast, Russia) has been assessed using the parameters of diffusion and convection–diffusion models. The found values of diffusion parameters match the data for other regions. In most cases, the convective flow of heavy metals is directed downwards and has a velocity of 0.126 to 0.31 cm/yr, or it does not differ from zero in a statistically significant manner. On the average, podzols and organic soils are similar in the diffusion parameters with regard to the total heavy metal content but differ in the velocity of convective transfer, which is much slower in organic soils. The model estimates for the inflow of heavy metal pollutants to soil do not depend on the distance from the plant, although a correlation with soil type is observable: an additional lateral influx of heavy metals to the surface most likely takes place in organic soils, associated with local depressions. An insufficient sample volume does not permit to assess the correlation of migration parameters with soil properties, while their correlation with chemical mobility (extraction with ammonium acetate buffer) appears as an insignificant trend.

Soil temperature was measured in the O horizon of Albic Podzol on two sites of strongly contaminated and damaged ecosystem from September 22 to July 10 in 2014/2015 and 2015/2016. The ecosystem is located 8 km to the north of the Severonikel industrial complex (the Kola Peninsula), the largest source of emissions of SO2 and heavy metals in Northern Europe. The aim of the study was to compare temperature regimes of technogenic barren soil without vegetation, which predominates in the ecosystem, and under a small group of depressed crowberry (Empetrum hermaphroditum) developing in the area in response to a decrease in the emissions from the Severonikel industrial complex. The results attest to significant differences between temperature parameters of the two sites. The soil under crowberry was characterized by significantly smaller temperature fluctuations during the entire period of observations and in the daily cycle. In autumn, the dwarf shrub maintained soil temperatures above zero for a longer period and mitigated first night freezing. Because of the dark color of the degrading O horizon of technogenic barren, this soil was characterized by higher daytime and mean daily temperatures in summer. In autumn, before the formation of a permanent snow cover, the soil of the barren site was subjected to stronger freezing in response to sharp decrease in the air temperature. Thus, even a depressed ground vegetation protects the soil from strong temperature fluctuations and ensures more stable conditions for the plant growth. The absence of the ground vegetation results in stronger soil drying in summer and in a sharper decrease in soil temperature in autumn. The soil overheating and strong drying in summer and the soil freezing in autumn can act as stress factors in addition to extreme contamination of the damaged ecosystems near the emission source for the survived trees and their seedlings.

The water-soluble components originated in coniferous litters desorb into solution the native organic substances from the solid phase of the eluvial horizons of podzols and podzolic soil. In podzols, the water-soluble organic matter (WSOM) extracted from litter and then passing through the E horizons are sorbed by the BFH horizons if their concentration in solution exceeds 35 mg C/L. The sorption ranges from tens to hundreds of milligrams of carbon per kilogram of the BFH horizon. The WSOM can be sorbed by the BT horizons of podzolic soil when the concentration of organic substances in the liquid phase is higher than in podzols. The model experiments with minerals show that kaolinite and illite interact with the soluble substances percolating from the litter and selectively extract more hydrophilic and less aromatic components with relatively low molecular weights. On the contrary, goethite interacts with the WSOM prevalently sorbing hydrophobic components, substances of phenolic nature, components enriched in aromatic carbon, and substances with molecular weights less than 7 kDa. The spectral characteristics of WSOM change after the sorption interaction with minerals: the fluorescence associated with the humus substances with the longest conjugation chain decreases or disappears, while new fluorophores containing fragments of phenolic and/or protein structures emerge. The presence of kaolinite and illite in the eluvial horizons and their interaction with WSOM most likely contribute to the transformation of WSOM composition and appearance of the properties maximally favorable for their sorption on iron hydroxides in the lower horizons.

Estimates of the spatial heterogeneity of the organic matter distribution in forest soils determined by the influence of the species and spatial structure of phytocenoses are relevant for many environmental problems, including the calculation of carbon sinks and modeling of the dynamics of forest ecosystems. We analyzed the data on the organic carbon (Corg) and total nitrogen (Ntot) contents in the O (forest litter) and AY (humus) horizons of Entic Podzols in the Prioksko-Terrasnyi Reserve (54.89° N, 37.56° E). The studied site is located in a coniferous–deciduous forest formed after overgrowing of the cutting area of pine stands. We sampled the O and AY horizons along transects between trees of different species, i.e., near the trunks, under the crown, and in the intercrown space. The contents of Corg and Ntot in the O horizon varied within 17.6–44.9 and 0.84–1.79%, respectively. The ranges for the AY horizon were greater: 0.71–8.5% (Corg) and 0.035–0.33% (Ntot). The relationship between the contents of Corg and Ntot in the O and AY horizons was close to linear (rs = 0.72 and rs = 0.96, respectively). We also obtained similar C : N ratios for the both horizons. The litter thickness and the content of Ntot in the O horizon, as well as the content of Corg in the AY horizon, significantly differed in different parts of the transects (P < 0.05). The differences in the litter thickness and the Corg content in the O horizon under the crowns of different tree species were also significant. In samples from the AY horizon taken in intercrown spaces, the Ntot content correlated with the demand of plant species of the ground cover for soil fertility. The data obtained reflect the influence of specific features of spatial patterns of surface and root litterfall in multispecies communities of mixed forest stands on the spatial variability of Corg and Ntot contents in soil.

Temperatures of sandy podzols of middle taiga pine forests with moss and lichen ground cover were analyzed which had been exposed to ground fires of low to medium intensity. In general, temperatures in lichen and moss plots of the pine forests under study, are close to each similar, but in the first year after a fire a noticeable contrast was observed. The reasons are an increase in the amplitude of daily temperatures on the soil surface and stronger heating of upper mineral layers. Temperatures in the mineral layer with depths up to 30 cm depend on the thickness of the forest floor. Analysis of the results show that the duration of post-fire effects in pine forests with sandy podzols is determined by a number of factors: the intensity of the fire, the degree of erosion of the ground cover and litter, and the recovery rate of these components.

This study presents a genetic characteristic of iron-illuvial podzols formed on an esker composed of coarse-grained and medium-grained sands, including the gravel–pebble fractions with boulders. We have revealed quantitative differences in the composition and properties of iron-illuvial podzols on the esker as compared to iron-illuvial podzols formed on sandy moraines under similar bioclimatic conditions. These differences are related to the topography and specific lithological composition of rocks in the esker. Fluvioglacial deposits are usually described without their specification into intraglacial deposits, forming esker, and periglacial deposits formed beyond the glacier. However, this is insufficient, taking into account the differences in the topography and rocks of eskers.

The content and profile distribution of 137Cs in iron-illuvial dwarf and shallow-podzolic podzols (Albic Podzols) under bilberry-lichen and green-lichen-bilberry pine forests in the located near the Kola Nuclear Power Plant have been analyzed. The pollution density (reserve) of 137Cs in the root-inhabited layer (0–30 cm) in the studied soils was significantly lower than the established control level of 37 000 Bq/m2 and amounts to 530–2459 Bq/m2. A significant part of 137Cs (60 to 90%) was concentrated in mineral horizons. It has been shown that the pollution density of 137Cs in the observation zone of a nuclear power plant was mainly due to global fallout. The greatest influence on 137Cs accumulation in the studied soils was exerted by the organic matter reserve.

Summary Profile-differentiated soils of the Precarpathian region were formed due to the combined effect of such processes as podzolization, lessivage, gley-eluvium. For the diagnosis of these soils, researchers have used different diagnostic features. The most controversial is the diagnosis of the lessivage process. Based on our own field and analytical studies, it is suggested to use the granulometric composition compared to the contents of the horizon and the silt content in argillanes for the diagnosis of lessivage argillanes within the illuvial horizon. A reliable feature of lessivage is the equal distribution of the montmorillonite group minerals within the profile, which is diagnosed by the ratio of SiO2:Al2O3 in the silty fraction, the accumulation of Fe2O3 and R2O3 in the illuvial horizon in comparison with the rock and positive values of eluvial-accumulative coefficient of oxides in the silty fraction in the illuvial part of the soil profile.

This paper aimed to characterize urbostratozems (Urbic Technosol, WRB) of Saint Petersburg located in industrial (“Electrodepo” railway station) and residential (region Polish Garden) zones. These soils were also compared with background (natural) soddy podzol soil (Umbric Albic Gleic Podzol, WRB) sampled in recreational zone (suburban park “Oranienbaum”). Soil samples were collected from soil horizons for chemical analysis and from top of soils for microbialogical analysis in June of 2012. Chemical properties (pH, total organic carbon, mobile forms of K and P) and content of heavy metals (Pb, Cu, Zn, Ni) in soils were determined. Culturable forms of microorganisms (bacteria and fungi) were studied. Assessment of the enzymatic activity of the soil was carried out by culturing of microorganisms-producers of protease, amylase, cellulase and lipase on special media. Biotesting using cress (Lepidium sativum L.) seeds had been carried out for assessment of soil phytotoxicity. It was found that chemical properties of urban and natural soils differ greatly. Heavy metal pollution was evident in both urban soils, but maximum concentrations of heavy metals were found in the soil of the industrial zone. Phytotoxocity had been also most pronouncend in the soil of the industrial zone. The natural soil exhibited significantly higher respiration activity than urbostratozems. The greatest difference in the structure of the bacterial and fungal communities was observed between the natural soil of the recreational zone and the urbostratozem of the industrial zone. Algae had been present in the urban soils of the residential zone that was not observed in the natural podzol. The minimum number of producers of all enzymes, except for cellulase, was observed in the soddy podzol in the recreational zone. The maximum number of protease and amylase producers was found in the soil of the industrial zone. Lipolytic activity was almost the same in all samples. It was found that more sensitive biological methods are needed for environmental assessment of urban soils. The results of the article can be used by soil scientists and environmental engineers for a comprehensive environmental assessment of the condition of urban soils and for creating new urban green spaces.

The composition of water-soluble organic matter (WSOM) of coniferous- deciduous, coniferous, and moss litter was studied. Litter type affects the composition of WSOM. Sphagnum litter contains less N and dissolved organic carbon (DOC), but more carbohydrates, the WSOM from this litter is characterized by the lowest extinction coefficients Е254. WSOM from mixed litter with a predominance of birch litter had a maximum content of N and a small amount of soluble phenolic (SP) substances. WSOM from litter of pine needles differ from the rest by having a lower content of carbohydrates, the maximum amount of SP and hydrophobic fractions. All investigated WSOM were characterized by high rates of decomposition: half-decomposition time of their stable fractions was 2–4 months. WSOM from pine litter at pH ~ 6.5 were absorbed by the BF horizon of iron–illuvial podzol, starting from the concentration of DOC of 100 mg/L. Substances from birch–spruce litter were adsorbed insignificantly under similar conditions.

For agricultural soils with low natural fertility, the possibility of using rock powders as an alternative source of nutrients and/or improver of soil physical parameters is under discussion and study. Shungite rocks, carbon-bearing volcanic sedimentary rock, are characterized by a high content of carbon and nutrients. This study aimed to evaluate whether shungite application to Umbric Podzols may affect leaf and root mitochondrial respiratory pathways, and the leaf response to temperature change. A pot culture experiment was conducted with Allium cepa L. seedlings, using soil shungite concentrations of 0, 5, 10, and 20 g kg−1 and two soil water regimes: well-watered (WW) and drying-wetting (DW) cycles. Soil water deficit increased total respiration (Vt) of onion leaves, but not roots, under low (13 °C) and high (33 °C) measurement temperature. Shungite application affected leaf Vt only at 13 °C: it increased the Vt rate under WW and decreased one under DW. An increase in the measurement temperature to 33 °C enhanced the sensitivity of leaf respiration to the inhibitor of the alternative respiratory pathway (salicylhydroxamic acid, SHAM). Shungite application increased the contribution of SHAM-sensitive pathway to the leaf Vt rate under WW, but not under the DW regime, regardless of the leaf temperature. In contrast to the SHAM-resistant pathway, the temperature sensitivity of the SHAM-sensitive rate decreased following the decrease in soil water availability. Shungite application increased the temperature sensitivity of both SHAM-sensitive and SHAM-resistant pathways under DW, and significantly decreased these parameters under WW. In summary, the decrease in temperature sensitivity of alternative SHAM-sensitive respiratory pathway with a decrease of soil water availability or shungite-related decrease of both SHAM-sensitive and SHAM-resistant leaf respiration may play an important role in enhancing the resistance of plant respiration to stress temperature.

Lead (Pb) as one of toxic elements occurs naturally in nature. Its use in metalurgical activities, mining and combustion of coal, waste incineration and use as a additive to gasoline in the past has endangered environment and health of oranisms. We determined the Pb isotopic composition in two podzol profiles, in a forest and nearby a road, using ICP MS. Based on the 206 Pb/207 Pb vs 208 Pb/206 Pb ratios we assesed the main source of Pb in O, Ah, Bhf, and Bf horizonts in both soil profiles and Ep horizont from profile P2 to be coal combustion. The source in eluvial Ep horizont from profile P1 and C horizonts originated in lithogenic Pb with values 206 Pb/207 Pb 1,126; 1,198 and 1,193. From Pb isotopic ratios we can conclude that during podzolization antropogenic Pb move to the deeper parts of soil profiles.

Little information is available on the effect of soil-improving cropping systems (SICS) on crop productivity on low fertility sandy soils although they are increasingly being used in agriculture in many regions of the world due to the growing demand for food. The study aimed at quantifying the effect of four soil-improving cropping systems applied on sandy soil on cereal productivity (yield of grain and straw and plant height) in a 4-year field experiment conducted in Poland with spring cereal crops: oat (2017), wheat (2018), wheat (2019), and oat (2020). The experiment included the control (C) and the following SICS: liming (L), leguminous catch crops for green manure (LU), farmyard manure (M), and farmyard manure + liming + leguminous catch crops for green manure together (M + L + LU). To quantify the effect of the SICS, classic statistics and the Bland–Altman method were used. It was shown that all yield trait components significantly increased in the last study year (2020) under SICS with M and M + L + LU. All yield trait components were significantly lower in the dry years (2018–2019) than in the wet years (2017 and 2020). The relatively large rainfall quantity in May during intensive growth at shooting and the scarce precipitation during later growth in the dry year 2019 resulted in a significantly greater straw yield compared to the other dry year 2018. The values of Bland–Altman bias (mean difference between the particular SICS and the control) varied (in kg m−2) from −0.002 for LU in 2019 to 0.128 for M and 0.132 for M + L + LU in 2020. The highest limits of agreement (LoA) were in general noted for all yield trait components (the least even yield) in the most productive SICS including M and M + L + LU in the wet year 2020. The Bland–Altman ratio (BAR) values indicate that quantification of the effects of all soil-improving practices was most uncertain in the dry year 2018 for the grain yield and in the wet year 2020 for the straw yield and much less uncertain for the plant height in all SICS and study years. The results of this study provide helpful information about the effect of the SICS on the different yield trait components depending on the period of their application and weather conditions prevailing during the growing season.

The changes in the total soil carbon storage and the pools of labile and potentially mineralizable organic matter in Entic Folic Podzols of the Khibiny Mountains (Murmansk region, NW Russia) caused by wildfires of high and moderate intensity and during the post-fire succession are discussed. Although a moderate-intensity wildfire has no statistically significant impact on the total soil carbon pool, it triggers the active erosion processes leading to the carbon losses comparable to the direct pyrogenic carbon losses in a high-intensity fire. In the postfire soil restoration, the type of organic carbon accumulation changes: the surface carbon accumulation in the form of peat is characteristic of the control site, while up to half of soil carbon is accumulated in the mineral horizons at late stages of the postpyrogenic succession. A high-intensity fire leads to almost complete destruction of labile, microbial, and potentially mineralizable carbon pools in both the organic (pyrogenic) and mineral horizons. A moderate-intensity fire does not cause any statistically significant changes in these pools as compared to the control. The restoration dynamics of the labile and potentially mineralizable pools of organic matter in the pyrogenic horizons of soil differ: the trend of a steady increase in the pools of labile and microbial carbon is observed for three years after the fire and later, while the pool of potentially mineralizable carbon reaches its maximum three years after the fire and then becomes stabilized at this level.

The post-anthropogenic and soil cover transformations of former agricultural soils on the abandoned lands in the Russian Arctic territory are poorly investigated due to the active growth of the city complexes and increasing area occupied by agricultural lands. That is lead to an increase in the area of the arable lands surrounding the polar urbanized territories. Today, most of that land allocated for agricultural needs has been abandoned or affected by other types of land use. This study aimed to investigate the abandoned lands surrounding some of the settlements in the central part of the Yamal region. The soil diversity, morphology, and chemical and agrochemical properties were investigated with special reference to the specific transformations that occur to fallow lands under permafrost-affected cryogenic-ecosystem conditions. Analysis of data show that these soils are characterized by features relating to both, previous (and existing), anthropogenic impacts and natural processes such as cryogenic mass transfer. The degradation of the arable humus-enriched horizon was not as pronounced as it has been in more humid boreal environments over recent decades. The organic carbon content in topsoil depends on the land use and varied considerably among the soil types. The former arable topsoil horizon has been stable over time in terms of its morphological features and agrochemical state. Despite the high soil acidity levels, thenutrient content in the anthropogenically impacted soils was still high, even though being abandoned for 20 years.

Long-term research data have been used to compile a soil map of the most transformed part of the gas-condensate field in the Middle Angara region. The studied area is assigned to the North Baikal mountainous province with podzolic (Podzols), soddy-podzolic (Retisols), peat-podzolic (Histic Podzols), peat-cryozemic (Histic Cryosols), gray-humus (Cambisols), and dark-humus (Phaeozems) soils. The natural diversity of the soil cover and the content of macro- and microelements in soils have been determined. In soils near some gas-condensate field facilities, the contents of oil products, lead, zinc, nickel, and chrome exceed the background values and health and safety standards. The chemical composition of soil water in the area has changed, and chloride soil salinization is recorded. Ecological zoning of the area with respect to its significance for humans and ecosystems and soil susceptibility to anthropogenic loads has been performed. A larger part of the gas field is suitable for the development, except for permafrost taiga areas, valuable virgin landscapes, and vulnerable soils of steep slopes. The zone requiring rehabilitation measures with subsequent extensive use includes the areas with strongly disturbed ground cover and the sod layer.

The properties of representative soil profiles of podzols included in the database of the Unified State Register of Soil Resources of Russia are considered. As a result of processing and analysis of the data array (53 measured profiles), the ranges of values of a number of parameters have been corrected. It has been revealed that, in most cases, the ranges of properties of podzols are wider as compared to the estimated profiles given in published works (the thickness of the Al–Fe–humus horizon and the humus content in the E horizon). However, the range of values of the humus content in the illuvial horizon is narrower. We revealed specific features of podzols in particular regions received as a result of consolidation of soil provinces of the Map of Soil–Ecological Zoning. Regularities can be seen in the geographical distribution of the thickness of profiles of these soils and the content and profile distribution of humus. The humus content is maximal in the eluvial soil horizons in Siberian regions and in the illuvial soil horizons in the European Russia and Primor’e.

The geochemically conjugate series of soils (Albic Podzol – Albic Podzol Gleyc – Hystosol) formed on an undulating glaciolacustrine plain in the middle taiga of Karelia was investigated. Surveys for redox conditions showed them to vary from oxidizing in automorphic soils to reducing in soils occupying accumulation-favoring locations. The geochemical coefficients descriptive of the features of accumulation and directions of migration in the studied soils were calculated and analyzed. The distribution of silicic acid and a majority of sesquioxides inside the profile of the studied soils is typical of podzols. The podzolic horizons of the soils occupying interstitial positions have a faster outmigration of elements than in automorphic soils, while their Al-Fe-humic horizons accumulate aluminum, iron, titanium and phosphorus. All the soils are deficient in a majority of microelements as compared to their background levels; very low concentrations were determined for nickel, cobalt and manganese. The content of copper and sometimes zinc is at the background level. The distribution of the studied elements across the soil profile follows the accumulation-eluviation-illuviation pattern, but the scope of variation in the migration of elements varies among topographic positions. In well-drained locations microelements are quite monotonously distributed through the lower part of the soil profile, while soils in transitional landscapes have a higher differentiation of microelements. The differentiation of the catena through lateral migration is of the transient eluviation type, i.e. soils in lower-lying positions are poorer in the studied elements than soils in automorphic positions. This pattern is due to the natural characteristics of the area: low surface slope, homogeneous sandy parent material, low humus content in soil.

The contents, distribution in the profile, and migration capacity of 238U in automorphic podburs (Entic Podzols) and hydromorphic alluvial (Fluvisols) soils of natural and human-transformed landscapes of southern Yakutia are analyzed. Human-transformed (technogenic) landscapes of southern Yakutia, including the Elkon uranium deposit area, in particular, are characterized by two distinct types of element migration in soils: the aero-technogenic and the hydro-technogenic migration. These types of element migration determine the level of 238U pollution of soils, the distribution pattern of 238U in the soil profiles, and the proportion between 238U compounds with different migration capacity. The soils subjected to the radioactive contamination are characterized by the increased mobility and migration capacity of 238U isotopes in comparison with the unpolluted soils of natural landscapes. Also, in contrast to automorphic podburs, hydromorphic alluvial soils are characterized by the increased level of radioactive pollution and higher concentrations of mobile uranium compounds.

Bisequal soils in northern Wisconsin were described and characterized with the intent to determine if a near total elemental analysis protocol may estimate the effect of selected soil pedogenic pathways on soil morphology. The protocol reveals that gross elemental soil profile distributions do provide evidence that certain pedogenic processes are operating within a group of soils. Concentration differences between instrumental neutron activation analysis and an aqua regia digestion protocol infer that alkali metals, alkaline earth metals, transition metals and the rare earth elements are only incompletely weathered from primary minerals. Transition metals, alkali metals, alkaline earths, metalloids, and the rare earth elements all show inter-horizon mobility. Lessivage and the mobility of elements presumably adsorbed on soluble or suspended organic materials are the dominant soil processes influencing the soil profile redistribution of elements and the majority of these elements are shown to correlate with the soil profile distribution of Fe. Base cycling by the forest vegetation was shown to support A horizon enrichment of Ca, Sr, Ba, P, S, Mn, Zn, Sn and Pb. For clinical practice, elemental analysis may reveal important soil profile elemental differences when applied to variation of one soil forming factors, such as a chronosequence or toposequence within a landscape or soil association. Advantages and limitations of the protocol in identifying pedogenic pathways are discussed.

In the years 2014–2017, a field experiment was carried out, in which two types of waste were applied to soil. One of them was mineral waste – carboniferous rock from a hard coal mine, and the other – organic waste – post-fermentation sludge from agricultural biogas-producing plant. The experiment was an example of an action, in which soil management was associated with their drainage effects on the soil. The waste was applied to the light soil of low utility value, included in the V bonitation class (in polish soil quality classification) and the 6th complex of agricultural suitability (weak rye). According to the WRB classification, it was Haplic Podzol (PZha) developed from the post-glacial sand. The aim of the study was to analyze changes in soil compaction caused by a single introduction of waste. During the four-year study (2014–2017), the durability of these changes was also observed. It was found that the best effects of reducing the soil compaction were obtained as a result of the combined application of two wastes: carboniferous rock and post-fermentation sludge. Introduction of waste into the soil was also permanent, as differences resulting from the soil management continued in the fourth year of the experiment.

Several studies related to CH4 cycling focus on the effect of elevated atmospheric CO2 levels on soil methanogenesis and methanotrophy. However, periodically waterlogged soils are characterized by much higher CO2 concentrations, while aggregates forming in arable soils due to traditional cultivation may be a natural CH4 source for low-affinity methanotrophs. We present a comprehensive laboratory investigation into both methanogenesis and methanotrophy in three different soils under ambient and high CO2 concentrations. The tested materials were agricultural soils widely distributed in Europe: Eutric Cambisol, Haplic Podzol and Mollic Gleysol with determined properties: Corg, Ntot, clay, silt, sand, pH, NO3−, NH4+. We conducted two independent experiments on methanogenesis (flooded conditions) and methanotrophy (non-flooded conditions). All samples for both studies were divided into three sets which differed in the initial CO2 concentration in headspace: ambient CO2 (0.03% v/v ± 0.005), and two high CO2 levels (5% ± 0.4 and 10% ± 0.5 v/v CO2). Moreover, 1% (v/v) of CH4 was added to all sets prepared for the methanotrophy test since low-affinity methanotrophy in the tested soils had been reported previously. Gas concentrations (CH4, CO2, O2) in headspace were measured using gas chromatography method. We observed that the examined soils differed in their ability to produce CH4 as follows: Haplic Podzol = Eutric Cambisol > Mollic Gleysol, as well as to consume CH4: Mollic Gleysol > Haplic Podzol > Eutric Cambisol. The CH4 emissions started faster in Gleysol, but the final CH4 concentration and CH4 production rate in this soil were significantly lower than in the two other soils. The CH4 uptake rate significantly differed among the tested soils. The MANOVA confirmed the significance of the soil-type factor in determining both process rates, whereas the effect of CO2 level and the interaction between both factors were not significant. The amount of consumed O2 during CH4 oxidation was also characteristic for examined soil, but did not differ significantly between CO2 variants. CH4 production and consumption in three different soils (Eutric Cambisol, Haplic Podzol and Mollic Gleysol) collected from periodically waterlogged arable fields were more strongly affected by soil properties than by high CO2 concentration. In contrast, the high CO2 level significantly decreased CO2 production accompanying tested the CH4-related processes.

On the basis of the profile-genetic approach, diagnostic features of poorly studied mountainous soils under larch forests and woodlands in different geomorphic positions of the Subpolar Urals were identified, and their classification position was determined. The morphological, physicochemical, and chemical characteristics of the studied soil profiles were described. It was found that the soil cover under blueberry–moss larch stands is mainly composed of iron-illuvial svetlozems and iron-illuvial podzols. Both soils were identified as Albic Podzols (Skeletic) in the WRB-2015 system. On the outcrops of calcareous rocks on slopes of river valleys, gray-humus soils (Calcaric Leptosols (Skeletic)) and iron-illuvial podzols were described. They occupy small areas and can be referred to as rare soils in the studied region. Near the upper treeline, lithozems (Lithic Leptosols (Skeletic)) and podburs (Entic Podzols (Skeletic)) are developed; these soils are common in the mountainous tundra landscapes. The accumulation of plant litter on the soil surface and its slow mineralization predetermine the raw-humus and peaty nature of the upper horizons with a broad C : N molecular ratio.

On the Kola Peninsula, peat bog soils and Al–Fe-humus podzols (according to the WRB classification, Cryic Ombric Fibric Histosols and Folic/Histic Albic Podzols, respectively) are the most common. However, comparison of their level of pollution with heavy metals (HM) has never been carried out. The purpose of this work is a comparative analysis of the level of HM pollution of the upper horizons of peat bog soils and Al–Fe-humus podzols in the impact zone of the copper-nickel plant. Soil testing was carried out in 37 closely located habitats (forest and swamp) situated in the zone of atmospheric emissions of the Severonickel plant (Murmansk region). The total content of Ni and Cu in soil samples was determined by atomic absorption spectrometry after their dissolution in a mixture of concentrated acids HNO3 and HCl. Statistical analysis of the soil analysis results was carried out in Statistica 12 using nonparametric Kruskel – Wallis, Mann – Whitney and Wilcoxon tests. It was established that both types of studied soils did not significantly differ in the total content of HM in the upper horizons of the soil profile. The level of pollution of compared soils is determined by the distance from the source of pollution, the rose of the prevailing winds and the orography of the terrain. The Ni content in almost all soil samples exceeds the Cu concentration, which is due to the excess of atmospheric emissions of technogenic Ni compounds compared to the content of Cu compounds in them. The phytotoxicity of both types of studied soils varies widely: from its complete absence to a high and very high degree. At the same level of soil pollution with HM swamp habitats are more prosperous due to better moisture content of peat bog soils.

Concentrations of lanthanides (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Lu) were measured in soils and soil water from a hillslope transect in the Krycklan catchment in northern Sweden. Soil water was collected at different depths and at different distances from the draining stream – from the uphill Podzol to the peaty riparian zone – throughout the course of a year. Combined with soil profiles from the same sites this provided a comprehensive dataset to study the fractionation and transport of lanthanides from boreal forest soils to streams. The soil water was characterised by high concentrations of lanthanides in the riparian zone, more than an order of magnitude higher than in the uphill mineral soil, and when normalised against local unweathered till the soil water exhibited distinctly negative Eu anomalies, particularly in deeper soil layers. The soil samples displayed both positive and negative Eu anomalies, but positive Eu anomalies were primarily associated with strongly weathered soils, whereas negative soil Eu anomalies were observed in organic soils at depths were large amounts of lanthanides are transported towards the stream. Since reduction of Eu seems unlikely to occur in this transect, we propose that the Eu anomalies in soils and soil water are caused by the partial occurrence of Eu in more weathering-resistant minerals than the other lanthanides. Based on the collected data and the hydrological and biogeochemical understanding of the studied transect we therefore propose a conceptual model for how Eu anomalies arise and how they can be used to interpret the Holocene transport and accumulation of lanthanides in soils. The results suggest that Eu anomalies have the potential to become a powerful tracer for studying weathering and soil development.

Soils of the Pavlovsk Park–the largest landscape park in Europe—have been studied, and large-scale mapping of the soil cover of the main areas of the park has been performed. Limnoglacial and alluvial deposits are the predominant soil forming materials in the park. Iron-illuvial soddy podzols (Umbric Podzols) predominate among the natural soils of the park, and gray-humus stratozems (Hortic Anthrosols) underlain by the limnoglacial deposits and/or by the buried soils are the main human-transformed soils of the park. The areas of urbostratozems are mainly confined to the Slavyanka River valley. The thickness of human-created stratified layer of stratozems and urbostratozems varied from 40 to 120 cm. Soils with an acid reaction predominate in the park, except for the Slavyanka River valley, where most of the soils have a neutral or an alkaline reaction. The organic carbon content in topsoils ranges from 0.9 to 4.4%. The majority of the park soils are characterized by the low content of available potassium and by the considerable variability in the content of available phosphorus. The results of the soil survey may serve as the basis for further monitoring studies and be helpful in the development of measures for the conservation and restoration of the tree stands in the park.

Phosphorus (P) is the second most important macronutrient that limits the plant growth, development and productivity. Inorganic P fertilization in podzol soils predominantly bound with aluminum and iron, thereby reducing its availability to crop plants. Dairy manure (DM) amendment to agricultural soils can improve physiochemical properties, nutrient cycling through enhanced enzyme and soil microbial activities leading to improved P bioavailability to crops. We hypothesized that DM amendment in podzol soil will improve biochemical attributes and microbial community and abundance in silage corn cropping system under boreal climate. We evaluated the effects of organic and inorganic P amendments on soil biochemical attributes and abundance in podzol soil under boreal climate. Additionally, biochemical attributes and microbial population and abundance under short-term silage corn monocropping system was also investigated. Experimental treatments were [P0 (control); P1: DM with high P2O5; P2: DM with low P2O5; P3: inorganic P and five silage-corn genotypes (Fusion RR, Yukon R, A4177G3RIB, DKC 23-17RIB and DKC 26-28RIB) were laid out in a randomized complete block design in factorial settings with three replications. Results showed that P1 treatment increased acid phosphatase (AP-ase) activity (29% and 44%), and soil available P (SAP) (60% and 39%) compared to control treatment, during 2016 and 2017, respectively. Additionally, P1 treatments significantly increased total bacterial phospholipids fatty acids (ΣB-PLFA), total phospholipids fatty acids (ΣPLFA), fungi, and eukaryotes compared to control and inorganic P. Yukon R and DKC 26-28RIB genotypes exhibited higher total bacterial PLFA, fungi, and total PLFA in their rhizospheres compared to the other genotypes. Redundancy analyses showed promising association between P1 and P2 amendment, biochemical attributes and active microbial population and Yukon R and DKC 26-28RIB genotypes. Pearson correlation also demonstrated significant and positive correlation between AP-ase, SAP and gram negative bacteria (G−), fungi, ΣB-PLFA, and total PLFA. Study results demonstrated that P1 treatment enhanced biochemical attributes, active microbial community composition and abundance and forage production of silage corn. Results further demonstrated higher active microbial population and abundance in rhizosphere of Yukon R and DKC 26-28RIB genotypes. Therefore, we argue that dairy manure amendment with high P2O5 in podzol soils could be a sustainable nutrient source to enhance soil quality, health and forage production of silage corn. Yukon R and DKC 26-28RIB genotypes showed superior agronomic performance, therefore, could be good fit under boreal climatic conditions.

Placic (Bsm) horizons are commonly found in different types of soils worldwide, but are very rare in Ultisols. The formation of Bsm horizon and podzolization are different processes in pedogenesis. This study collected five podzolic Ultisols containing Bsm horizons from the subalpine forests in Taiwan to illustrate the morphological characteristics and genesis of the Bsm horizons in these soils with both clay illuviation and podzolization. The distinctive Bsm horizons were 3 to 10 mm thick and had abrupt and wavy boundaries with overlying albic (E) and underlying argillic (Bt) horizons. All Bsm horizons contained over 35% of clay fraction which significantly increased from E horizon to B horizons in the pedons. The Bsm horizons showed much higher bulk density than adjacent horizons above or below them, elucidating that such iron pans were relatively impermeable to water and plant roots. The maximum contents of pedogenic Fe occurred in the Bsm horizons mainly cemented by poorly crystalline Fe oxides associated with high amounts of organic matter and epiaquic conditions. Pedogenic Al appeared to be accumulated in the Bt horizons where spodic materials were identified according to the oxalate-extractable amount of Fe and Al. The polygenetic processes of these podzolic Ultisols with Bsm horizons were proposed as three stages. Firstly, clay illuviation predominantly occurred to form Bt horizon in the interglacial periods during the mid to late Pleistocene. Then, podzolization gradually became a major process to accumulate spodic materials in the Bt horizon because of the coniferous forest formation under the cool and humid climates close to the late Pleistocene; however, water was perched at the soil surface due to poor drainage and abrupt textural change between E and Bt horizons after the Holocene. Eventually, the reduced iron from E horizon was gradually re-oxidized and precipitated on the top of Bt horizon where exhibited oxidizing condition to form Bsm horizon until today. Because of the occurrence of Bsm horizon in these Ultisols, a new subgroup Placic Epiaquults, was therefore proposed to the keys to Soil Taxonomy.

Ageing of biochars in soil affects their surface properties and can cause changes in water vapor adsorption-desorption processes. Measurements of hygroscopic water contents and corresponding water potentials of non aged and 3-year aged biochars as well as of sandy soils with medium and high quality were carried out during 5 cycles of water vapor adsorption-desorption processes at a room temperature of 23.5 °C. The results showed a significantly lower content of maximum hygroscopic water in the aged biochars than that in the non aged biochar at the end of water vapor adsorption processes at high air humidity. A significantly higher affinity of the high quality soil to water vapor resulted in insignificant differences in the maximum hygroscopic water content and in significant changes in the corresponding water potentials as compared to the same properties of the soil with medium quality. Minimum content of hygroscopic water was significantly lower in the non aged biochar than in the aged biochars at the end of the water desorption processes at ambient laboratory atmosphere. There were insignificant differences in minimum contents of hygroscopic water and in the corresponding water potentials of the aged biochars from soils with medium and high quality.

Red spruce (Picea rubens) ecosystems in the high elevations of the central Appalachians of the eastern United States are the focus of ongoing restoration efforts due to the valuable ecosystem services these forests provide. Recent research has shown that spodic materials still present in the soil represent the pedomemory of the historic extent of red spruce forests in the region. A dataset containing 221 points with varying spodic intensities and 29 environmental variables collected from the Monongahela National Forest in West Virginia, USA, was used to evaluate the utility of a species distribution model, Maximum Entropy (MaxEnt), for predicting the presence of spodic properties. MaxEnt was selected for evaluation because, as a presence-only model, it inherently omits absence locations and thereby reduces the risk of including false absences (i.e., herein, locations that have undergone some level of depodzolization) unlike other models previously used to predict pedomemory. Model outputs that employed three different spodic intensity class inputs—very weak to strong expression, weak to strong expression, and strong expression—resulted in similar spodic probability predictions, though there was less area mapped as transitional probabilities in the strong expression model than the two models that included weaker spodic intensity input data. Permutation importance indicated that no single or small subset of environmental variables controlled the three model outputs, perhaps because the environmental covariates may have been too coarse or not strongly enough associated with podzolization processes to be very important. When the output from the MaxEnt model using the full range of spodic intensities (very weak to strong) was compared to an output produced using a presence-absence model (random forests), there was approximately 62% agreement (where both models predicted presence or both predicted absence) for the cells in the top 40% of the predicted probabilities.

Mineralization resistance of water-soluble organic matter (WSOM) extracted from litter of podzol becomes higher upon the interaction with mineral horizons. Both the portion of WSOM susceptible to mineralization and its mean decomposition rate decrease two and three times, respectively, after its migration through the E eluvial horizon. Sorption in the BF horizon enhances the stability of the input organic matter. The relative content of mineralized carbon decreases to 2% (eight times). In natural soils, adsorbed organic matter may be even more resistant to mineralization due to lower temperatures and biological activity and thus represent the basis for the formation of humus reserve. Taking into account the calculated mineralization rate, the organic carbon accumulation in the BF horizon as a result of WSOM sorption may reach 13.5 mg/100 g per year, but it depends on the concentration of organic substances in soil solutions, hydrological regime, and other factors.