Phenol compounds in solutions of soils of different types in the central forest state biosphere reserve

The interannual, seasonal, and daily dynamics of the contents of phenol compounds in the soil solution of a peat-podzolic-gleyic soil in the southern taiga are considered. The concentrations of phenol compounds in the studied soil remain relatively stable. In the solutions obtained from different soil types, the main limiting factor is the degree of hydromorphism, which manifests itself via the biological factor—the intensity of the microorganisms activity and the composition and quality of the forest litters.     

Characteristics of soil organic matter in temperate soils by Curie point pyrolysis-mass spectrometry.

This series of papers examines some significant differences in the constitution of organic matter found amongst major soil groups and their genetic and morphological horizons, as determined by the dynamic pyrolysis-mass spectrometry of whole soil samples. Multivariate methods of data analysis identify groups of co-variant mass ions which successfully partition samples in terms of the above soil categories, and correlate with other major properties such as humification and hydromorphism. This first study covers the A horizons from a group of 22 Scottish soils chosen from the major temperate soil groups including brown forest soils, podzols, and noncalcareous, peaty and humic gleys (phaeozems, cambisols, podzols and gleysols). The principal components analysis of 52 mass ion intensities was found to partition the soils successfully in terms of two main factors which represented 62% of the total statistical variance. The first factor was found to correspond closely to the extent of hydromorphism, being high for highly gleyed A horizons, and depended chiefly on the presence of aromatic hydrocarbon ions. The second factor corresponded to the extent of mull humus formation, being high for brown forest soils (phaeozems, cambisols) and low for podzols, and depended chiefly on the abundance of polypeptide products relative to polysaccharide products. This second factor was evidently a more comprehensive expression of a humification factor found in previous studies. The relationships of these factors with C and N content and with base status properties were examined.     

Ecological-geochemical assessment of hydrocarbons in soils of Northeastern European Russia

The background contents of hydrocarbons (HCs) in soils of the far-northern and northern taiga of the Komi Republic were assessed. It was found that the soils of accumulative landscapes are enriched with HCs in comparison with the soils of eluvial landscapes. The differentiation of the HCs among the soil genetic horizons is more pronounced in the soils developed on loamy parent rocks (gley-podzolic and bog-podzolic soils) and less pronounced in the soils developed on sands (podzols and humus-illuvial bog-podzolic soils). The organic, litter, and illuvial horizons serve as a geochemical barrier in the pathway of the HC migration within the soil profile. A database for the mass fractions of HCs in the soils was created using GIS technologies, and a sketch map of the HC distribution in the soils was developed on its basis. The results obtained for the back-ground content of HCs are used for assessing the contamination of soils with oil and oil products and for gaining ecological expertise in the development of regional deposits of natural resources (raw hydrocarbons).     

Soils of the northern part of the Subpolar Urals: Morphology, physicochemical properties, and carbon and nitrogen pools

The morphology and physicochemical properties of mountain-tundra and mountain-forest soils of the Subpolar Urals are analyzed. Gleyic humus-illuvial podburs, in combination with humus-illuvial podburs and raw-humus gleyzems, predominate in the mountain-tundra zone; permafrost-affected gleyzems and peat gleyzems with a shallow (30–50 cm) permafrost table are developed on colluvial fans at the foots-lopes. Iron-illuvial podzols, iron-illuvial svetlozems, eluviated burozems, texture-differentiated podzolic soils with a microprofile of a podzol, and gleyed peat-podzolic soils occur in the mountain-forest zone. The organic carbon and nitrogen pools in the soils considerably vary depending on the soil type and local landscape conditions. The organic carbon pool stored in the upper 50 cm of the soil profile varies from 7.7 to 39.3 kg/m² in the mountain-tundra soils and from 6.5 to 11.8 kg/m² in the mountain-forest soils. The corresponding values for the nitrogen pool are 0.4–2.4 and 0.4–0.8 kg/m², respectively.     

Morphological-genetic characterization of soils on the Enganepe Ridge

Specific features of the soil formation in the Polar Urals related to the slope aspects, parent rocks, and vegetation are considered using the example of the Enganepe Ridge. Soils of the same type (humus-illuvial podburs and podzolized podburs) are formed under the severe climatic conditions of the mountain tundra belt irrespective of the slope aspect. The main differences in the prevalent soils are manifested in the mountain belt of sparse forests. Under the sparse larch forests on the southeast-facing slope, illuvial-humus-iron podzols predominate. On the south-facing slope under the sparse spruce forests, clay-illuviated illuvialhumus-iron podzols alternate with mucky-dark humus soddy lithozems. Burozems are formed in a few ecological niches. The richness of the parent rocks, along with the southern slope aspect and the transitional-accumulative nutrient transfer, is shown to promote the formation of sparse spruce forests under the climatic conditions of the Polar Urals.     

Manganese, iron, and phosphorus in nodules of chernozem-like soils on the northern Tambov Plain and their importance for the diagnostics of gley intensity

Nodules (nodules) forming in the chernozem-like soils of flat-bottomed closed depressions on the northern part of the Tambov Plain differ in their morphology and chemical composition as related to the degree of hydromorphism of these soils. The highest are the coefficients of Mn, P, and Fe accumulation in the nodules from these soils. The Fe to Mn ratio grows with the increasing degree of hydromorphism. Under surface moistening, the maximal amounts of mobile Mn and Fe compounds were extracted from the nodules of the most hydromorphic podzolic chernozem-like soils; under the ground moistening, their greatest amounts were extracted from the least hydromorphic soil—the weakly gley soil. In the first case, the content of organic phosphates in concretions amounted to 30–50%; in the second one, 2–3% of their total content. Under surface moistening, the proportion of active mineral phosphates becomes higher with the increasing hydromorphism: from 30 (podzolized soil) to 70% (gleyic podzolic soil). Under ground moistening, on the contrary, their proportion decreases from 70–89% in the weakly gley soil to 40–50% in the gley chernozem-like soil. The possibility to determine the degree of hydromorphism of chernozem-like soils based on the coefficients of bogging is shown. The expediency of using Schvertmann’s criterion in these studies is assessed.     

Factors of the development of taiga and tundra soils with differentiation of Fe and Al oxides in the profile

Statistical data on the bulk contents of iron and aluminum oxides in iron-depleted and iron-enriched horizons of a wide range of taiga and tundra soils were compared. It was found that the soils could be arranged into the following sequence characterized by an increase in the relative contribution of iron oxides and a decrease in the relative contribution of aluminum oxides to the differentiation of sesquioxides in the soil profiles: sandy podzols—soddy-podzolic soils—loamy micropodzols and iron-illuvial svetlozems—cryogenic ferruginated gleyzems. It was concluded that the bleaching of eluvial horizons and the depletion of sesquioxides from them, as well as the accumulation of sesquioxides in the illuvial horizons, are controlled by different processes in different soils. In sandy podzols, the differentiation of sesquioxides is due to the Al-Fe-humus podzolization; in loamy micropodzols and iron-illuvial svetlozems, due to the redox-Al-Fe-humus podzolization; in podzolic and soddy-podzolic soils, due to the selective podzolization and lessivage; and, in cryogenic ferruginated gleyzems, due to the reduction-oxidation processes.     

Genetic features of soils in altitudinal natural zones of the Khibiny Mountains

The plant cover of the Khibiny Mountains is characterized by the well-pronounced altitudinal zonality: high-alpine barrens—lichen, dwarf shrub, and shrub tundra—elfin birch forest—spruce forest. Humic petrozems (Lithic Leptosols) under sparse vegetation are formed on the tops of the mountains. The soils of the tundra zone are represented by podburs on the eluvium of nepheline syenite; smaller areas are occupied by typical cryozems. Humus-illuvial podzols are developed from moraine deposits under elfin birch forests and open spruce woodland. The moraine deposits in the inner valleys of the Khibiny Mountains are enriched in the products of weathering of nepheline syenite. The humus-illuvial podzols developed from them differ from their analogues on plain territories in the higher humus content and less contrasting eluvialilluvial differentiation.     

Fertility of soils under spruce forests of the Khibiny Mountains

The development of fertility of soils on different parent rocks is considered for different types of spruce forests in the Khibiny Mountains. The spruce forests of Mts. Kuel??por, Vud??yavrchorr, Chil??mana, and Saami were the objects for the study. The results showed that the fertility level of the soils of the Khibiny Mountains was determined by the combined influence of the parent rock??s composition and the vegetation. The differences in the soil properties are mainly explained by the composition of the parent rocks. The pod-burs differ from the podzols by the higher contents of organic matter, nitrogen, and available nutrients. The podzols are the most acid soils there. The podburs of Mt Kuel??por developing on base-rich parent rocks are the most fertile. The differences in the fertility of the soils on the intrabiogeocenotic (tessera) level are related to the vegetation. The soils of the spruce and tall-grass tesseras are richer in nitrogen, calcium, and manganese as compared to the soils of the dwarf shrub-green moss, low-grass-dwarf shrub-green moss, and tussock grass-dwarf shrub tesseras.     

Characteristics of soil organic matter in temperate soils by Curie-point pyrolysis-mass spectrometry, III. Transformations occurring in surface organic horizons

In previous parts of this study, transformations of organic matter in mineral A and B horizons from a set of soils of temperate regions were characterised by Curie-point pyrolysis-mass spectrometry (Py/MS) and elucidated in terms of changes in the biopolymer composition. These changes were associated with the processes of eutrophic humification, illuviation and hydromorphism. Within the set (23 profiles from Scotland, chosen as representative of soil groups of the temperate zone) some 13 podzols and humic gleysols displayed raw humus surface horizons above their mineral A horizons.

The L, F and H layers of these organic horizons, where they were morphologically distinct, were successfully differentiated in terms of their biopolymer composition by Py/MS. These differences were of degree rather than kind. The principal components analysis of 50 ion intensities from the mass spectra demonstrated a single dominant factor of composition. The corresponding reconstructed factor spectrum showed, in the sense L→F→H, the loss of lignin and polysaccharide products derived from raw plant material and the increase of residual or humified structures characterized by homologous alkene and higher benzene pyrolysis products. Peat was found to be similar to the L and F material. The successful observation of these chemical differences by a rapidly applied method is contrasted with alternative indices of organic composition, C%, N%, C/N, and also with pH, none of which showed any significant differences between the L, F and H horizons.

The retarded process of humification which occurs in these horizons compares closely in terms of Py/MS with that occurring in anaerobic mineral soils and differs from the more rapid eutrophic humification in aerobic soils. The products resemble those from geochemical sediments.     

Diagnostics of manganese-iron nodules in soddy-podzolic soils at different degrees of gleyzation from their magnetic properties

The composition and magnetic properties of manganese-iron nodules in soddy-podzolic soils at different degrees of hydromorphism were studied. The data of chemical analysis, magnetic measurements, and X-ray diffraction analysis indicate that the nanoparticles of magnetite act as a strongly magnetic phase in these nodules. The distribution of strongly magnetic nodules in soils and the absence of correlation between the content of magnetite and the magnetic parameters of the enclosing soil material indicate that the nodule magnetite is of soil origin.     

Assessment of Soil Water Composition in the Northern Taiga Coniferous Forests of Background Territories in the Industrially Developed Region

The composition of soil water under coniferous forests of Murmansk oblast—an industrially developed region of northern Russia—was investigated. The studied objects were dwarf-shrub–green-moss spruce forests and dwarf-shrub–lichen pine forests on Al-Fe-humus podzols (Albic Rustic Podzols) that are widespread in the boreal zone. The concentrations and removal of organic carbon performing the most important biogeochemical and pedogenic functions were estimated. The results proved significant intra- and inter-biogeocenotic variability in the composition of atmospheric depositions and soil water. Carbon removal with soil water from organic and mineral horizons within elementary biogeoareas (EBGA) under tree crowns was 2–5 and 2–3 times (in some cases, up to 10 times) greater than that in the intercrown areas, respectively. The lowest critical level of mineral nitrogen (0.2 mg/L) was, as a rule, exceeded in tree EBGAs contrary to intercrown areas. Concentrations of sulfates and heavy metals in water of tree EBGA were 3–5 times greater than those in inter-crown areas. Significant inter-biogeocenotic variations related to differences in the height of trees and tree stand density were found. It is argued that adequate characterization of biochemical cycles and assessment of critical levels of components in soil water of forest ecosystems should be performed with due account for the intra- and inter-biogeocenotic variability.     

Ein Vergleich von Eisenpodsolen im östlichen Niedersachsen mit Podsolen unter borealem Nadelwald in Finnland

Iron podzols in eastern Lower Saxony compared with podzols under finnish boreal Pine forests Well developed iron podzols with orange-brown Bs-horizons poor in humus are found in isolated small areas of eastern Lower Saxony. Because of their similarity they were compared with finnish podzols under boreal pine forest. Similar soil morphology, low humus illuviation and unconsolidized Bs-horizons are common to both groups of podzols. Different are the smaller thickness of soil horizons and the higher amounts of Fe-oxides in B-horizons of finnish podzols. Despite high grade of activity (Fe_ox/d) this may be due more to iron oxide formation by silicate weathering (micas) than to podzolization. An interpretation of the german podzols as relics from boreal coniferous forests may be supposed but there is no significant evidence by the considered datas.     

Properties of soils in Southern Sikhote-Alin using the example of the Ussuri Reserve

The physical and physicochemical parameters of soils in the Ussuri Reserve presenting the typical soils of the Southern Sikhote-Alin were determined for the first time with consideration for the composition and structure of the soil cover. The soils in the surface horizons had loamy and clay loamy texture. It could vary depending on the overlain soil processes. All the soils were characterized by the minimum base saturation and an increase in the actual acidity down the profile. The organic matter was characterized by an abrupt decrease down the profile and the high mobility of the humus substances. The fractional-group humus composition was analyzed, and the humus status of the soils was characterized. The burozems were regarded as background soils, while a humus-illuvial podburs were referred to the rare ones. Recommendations were developed for the organization of soil monitoring with key test plots in different ecological conditions as examples.     

Unterscheidung der Subtypen Humus-, Eisenhumus- und Eisenpodsol

Differentiation of the subtypes humuspodzol, humus-iron podzol and iron podzol Humic podzols are characterized by a distinct Bh-horizon and deep humus illuviation (humic bands). They may be thus recognized by morphological features. Differentiation of humic podzols on layered sands, of humus-iron podzols and of iron podzols is only possible by quantitative analytical data. For that the ratio of pyrophosphate-extractable C/Fe is proposed: humic podzols (Bh) > 10, humus-iron podzols (Bhs) 3–10, iron podzols (Bs) < 3. For differentiation of soil varieties quantities of illuviated matter in the investigated illuvial subhorizons (Bh, Bhs, Bs) may be chosen.     

Characterization of humic acids from tundra soils of northern Western Siberia by electron paramagnetic resonance spectroscopy

Humic acids from polar soils—cryozems (Cryosols), gleyezems (Gleysols), and peat soils (Histosols)—have been studied by electron paramagnetic resonance spectroscopy. First information was acquired on the content of free radicals in humic acids from polar soils for the northern regions of Western Siberia (Gydan Peninsula, Belyi Island). It was found that polar soils are characterized by higher contents of free radicals than other zonal soils. This is related to the lower degree of humification of organic matter and the enhanced hydromorphism under continuous permafrost conditions. The low degree of organic matter humification in the cryolithozone was confirmed by the increased content of free radicals as determined by electron paramagnetic resonance, which indicates a low biothermodynamic stability of organic matter.     

Ferromanganese concretionary neoformations: A review

Based on the original and published data, the results of studying the properties, composition, genesis, and information significance of ferromanganese concretions in the soils of the taiga, broadleaved forest, and forest-steppe zones are summarized. The role of these neoformations in the field and analytical diagnostics of soils is analyzed. Some regularities of the changes in the chemical composition of ferromanganese concretions as related to the degree of the soil bogging or profile drainage were revealed. Under the regular increase in hydromorphism of the soils, the content of iron increases and that of manganese decreases. In this case, the ratio between the iron and manganese contents extracted by 1 N H₂SO₄ also increases. This ratio was named the coefficient of bogging. This coefficient is used in practice to assess the expediency of drainage of mineral soils. The participation of ferromanganic concretions in the accumulation of macro- and micro-elements is shown. A model experiment has revealed that ferromanganese nodules can be formed during a rather short time (1–2 years).     

Zonal features of Al-Fe-humus pedogenesis on moraine deposits in the Kola Peninsula

Zonal differences in the genetic features of Al-Fe-humus podzols developed from moraine deposits in the tundra, forest-tundra, and northern taiga zones are revealed. The coefficient of profile differentiation of podzols with respect to the bulk content of aluminum increases from the tundra (1.16) to northern taiga (1.33); the analogous coefficient calculated with respect to the bulk content of iron increases in the same direction from 1.63 to 3.73. The zonal differences related to the contents of the amorphous forms of aluminum and iron are more contrasting: the coefficients of the profile differentiation increase from 4–6 in the tundra to 20–39 in the taiga. Differences in the humus contents of podzols developed in different natural zones are mainly seen in the podzolic horizon.     

Altitudinal distribution of soil fauna in the Khibiny Massif

Data on the taxonomic and trophic composition, population density, and biomass of invertebrates in the soils of the main mountain vegetation zones of the Khibiny Mountains—taiga, subalpine, and alpine—are obtained. The degree of similarity between soil faunal complexes in different vegetation zones within the studied slope is higher than that between zonal biocenoses of Murmansk oblast. The mountain tundra zone differs from the zonal tundra in a higher population density and taxonomic diversity of invertebrates, which are similar to those in the northern taiga podzols. At the same time, invertebrate complexes in the mountain taiga zone are poorer than those in the zonal plain taiga soils. The analysis of invertebrate taxa present in all the studied mountain vegetation zones demonstrates similar effects of the altitudinal and latitudinal zonality on the species composition of invertebrates. A conclusion is made about a higher functional activity of saprotrophs in the high-humus soils enriched in biogenic elements of the Khibiny Mountains in comparison with the functional activity of saprotrophs in the zonal plain podzols.     

Specificity of the physical properties of soils in locally waterlogged landscapes in the lower reaches of the Don River

We studied the physical properties of chernozems subjected to local waterlogging because of different reasons. The secondary soil hydromorphism resulted in insignificant changes in the soil’s texture related to some redistribution of the elementary soil particles by the particle-size fractions. The physical clay content somewhat increased in the lower part of the soil profiles (in the B2 and BC horizons) at the expense of the clay particles. The bulk density of the waterlogged soils somewhat increased, particularly in the B2 horizon. The regular soil waterlogging worsened the soil’s structural status with a decrease in the content of the silt-size aggregates and an increase in the content of the coarse blocky aggregates. The changes in the soil’s structure can be considered a diagnostic feature of the locally waterlogged chernozems. The water stability of the aggregates increased due to the higher contents of the major cementing agents, including the soil humus and carbonates.