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1.
B. F. Aparin E. Yu. Sukhacheva A. M. Bulysheva M. A. Lazareva 《Eurasian Soil Science》2018,51(9):1008-1020
The origin, structure, composition, and properties of soil humus horizons in functional zones of St. Petersburg have been studied. The radiocarbon age of organic matter in the humus horizons varies from 500 to 2700 years, which attests to the natural origin of humus. The structure of microbiomes in the humus horizons of soils under different plant communities has its specific features. The taxonomic structure of microbial communities at the phylum level reflects both genetic features of natural soils and the impact of anthropogenic factors, including alkalization typical of the studied urban soils. Tomographic studies have shown that the transporting system of humus horizons is less developed in the anthropogenically transformed soils in comparison with the natural soils. It can be supposed that the intensity of water and gas exchange in the anthropogenic soils is much lower than that in the natural soils. The fractional and group composition of humus in the urban soils is specified by the long-term pedogenesis, on one hand, and by the impact of metabolic products of the city and the factors of soil formation in the megalopolis, on the other hand. Bulk density of the humus horizon in the urban soils is higher than that in the natural soils; the portion of overcompacted humus horizons in the urban soils reaches 44%. Humus horizons of the lawns along highways are most contaminated with heavy metals: Pb, Zn, and Cu. There are no definite regularities in the distribution of major nutrients (NPK) in the humus horizons of anthropogenic soils. 相似文献
2.
Soils with intricate patterns of their humus profiles developing in the neutral-calcium landscapes of the southern taiga of
Western Siberia under highly dynamic paleogeographic, climatic, and weather conditions are characterized. The specific features
of these soils comprise the diverse modern humus horizons along with the relic ones of different preservation rates, shallow
leaching of carbonates, and a weak development of the middle-profile soil horizons. Specifying these organo-accumulative soils is substantiated by their high humus content against the geochemical
background of the clayey calcareous parent rocks. The conjugated series of soils reflect different stages of the soil evolution
(the humus profile degradation, the development of eluvial process, and the increase of contrasts in the acid-base conditions)
and the hydromorphic transformation accompanied by the formation of organic horizons making the humus profile more complicated.
In accordance with the diagnostic horizons, the position of the soils studied was determined in the Classification and Diagnostics of Soils of Russia. The relic enrichment of the humus horizon is proposed to be used as a specific feature of these soils. 相似文献
3.
On the interfluves and in small depressions of the Ryazan forest-steppe, under periodic stagnation of surface water, acid chernozem-like soils with a relatively thick humus horizon, podzolic horizons, and marble-colored gleyed B1 and B2 horizons are formed. The eluvial horizons of these soils contain Mn-Fe nodules, and dark humus coatings occur in the illuvial horizons. In the spring, the eluvial horizons of these soils are excessively moistened and gravitational water stagnates on the soil surface for 3–4 weeks. The formation of the acid light-colored eluvial horizons of the soils on leached rocks is related to gleying under the conditions of the stagnant-percolative regime. Their total thickness is 15–25 cm and more. According to the properties of their solid phase, these horizons are similar to the podzolic horizons of soddy-podzolic gleyed soils. These soils have not been represented in the classification systems of soils of the USSR and Russia. Based on the principles of the substantial-genetic classification, one of the authors of this article [9] referred this soil to gleyed podzolic chernozem-like soils, thus, considering it as an individual genetic soil type. The gleyed podzolic chernozem-like soils differ from the leached chernozems by their low productivity and difficulty of tillage. In humid and moderately moist years, the death of crops or a reduction in yield are probable because of the excess of moisture. 相似文献
4.
P. S. Lozovitsii 《Eurasian Soil Science》2012,45(3):290-302
The results of long-term studies (1957–2007) of the changes in the morphology of soil profiles and in the reserves and fractional
composition of the humus in the soils of the Ingulets irrigation system are discussed. After 50 years of irrigation, the boundaries
of the genetic horizons shifted downward by 15–30 cm. The redistribution of the humus took place: its content decreased to
a low level in the plow layer of the irrigated and rainfed soils and significantly increased in the layer of 60–100 cm so
that the reserves of humus in the layer of 0–100 cm somewhat increased and corresponded to a moderate level. The distribution
of humus in the soil profiles was characterized by the gradual lowering down the soil profile. The concentration of nitrogen
in the humus of the irrigated southern chernozems was very low. The degree of humification of the soil organic matter was
high. The humus was of the humate type in the upper horizons and of the fulvate-humate type in the lower horizons. 相似文献
5.
The results of experimental studies of the postagrogenic transformation of loamy soddy-podzolic soils on the southern slope of the Klin-Dmitrov Moraine Ridge are discussed. A chronosequence of soils (arable soils (cropland)-soils under fallow with meadow vegetation-soils under secondary forests of different ages-soils under a conventionally initial native forest) was examined, and the stages of the postagrogenic transformation of the automorphic soddy-podzolic soils were identified. The differentiation of the former plow horizon into the A1 and A1A2 horizons (according to the differences in the humus content, texture, and acidity) served as the major criterion of the soil transformation. A stage of textural differentiation with clay depletion from the uppermost layer was identified in the soils of the 20- to 60-year-old fallows. The specificity of the postagrogenic transformation of the soils on the slopes was demonstrated. From the methodological point of view, it was important to differentiate between the chronosequences of automorphic and semihydromorphic soils of the leveled interfluves and the soils of the slopes. For this purpose, a series of maps reflecting the history of the land use and the soil cover pattern was analyzed. The cartographic model included the attribute data of the soil surveys, the cartographic sources (a series of historical maps of the land use, topographic maps, remote sensing data, and a digital elevation model), and two base maps: (a) the integral map of the land use and (b) the map of the soil combinations with the separation of the zonal automorphic, semihydromorphic, and erosional soil combinations. This scheme served as a matrix for the organization and analysis of the already available and new materials. 相似文献
6.
V. A. Semal’ 《Eurasian Soil Science》2010,43(3):278-286
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. 相似文献
7.
The influence of 15 parameters of atmospheric and soil climates on the distribution of 12 genetic soil horizons (humus, eluvial, illuvial, and metamorphic) in the soils of Russian plains was studied. Quantitative characteristics of the relationships between these climatic parameters and the distribution of soil horizons were estimated by the rank correlation method. The initial dataset was prepared with the use of digitized maps in the MapInfo program. The results of our study made it possible to estimate the climatic parameters with respect to their impact on the formation of soil horizons. The difference between precipitation and potential evaporation, evaporation, and bulk atmospheric moistening of the soils proved to be the most significant climatic parameters affecting the distribution of soil horizons. These characteristics reflect the redistribution of moisture under the influence of temperature factors. The weakest correlation with the distribution of soil horizons was found for the index characterizing the depth of penetration of temperatures >10°C into the soils. 相似文献
8.
The effects of agricultural use on the structure and physical properties of three soil types 总被引：4，自引：0，他引：4
H. Dom&#x; J. Hodara A. S&#x;owi&#x;ska-Jurkiewicz R. Turski 《Soil & Tillage Research》1993,27(1-4):365-382
This investigation was carried out to determine the influence of the use of soils on their morphological structure and properties. Three soil types (i.e. Haplic Phaeozem derived from loess, Orthic Luvisol derived from loess and Orthic Luvisol derived from sandy loam) were involved. In each soil unit, profiles lying at a small distance from one another were taken for detailed examination. The main difference between the soils within each unit was the use to which they were put. The following soils were selected for evaluation: (A) soil from natural forest habitat; (B) soil cultivated in farms with a very low level of mechanisation; (C) soil cultivated in farms which had been completely mechanised for many years; (D) soil used for many years in a vegetable garden, similar to hortisol.
In the selected profiles the morphological features, soil structure in all genetic horizons, granulometric composition, humus content, pH, density, air and water capacity and air permeability were analysed.
It was found that the transition from forest soil management to agricultural use leads not only to the formation of an arable-humus horizon and to changes in structure but also to changes of the physico-chemical properties of soils. Soils under agricultural use manifest a lower level of acidification than forest soils, as well as a different distribution of organic matter. In all agricultural soils, increased compaction of humus horizons was observed, compared with the corresponding horizons of forest soils, as well as changes in other physical features. The use of heavy machines over many years in field operations results in increased density of the soil and deterioration of soil structure. This effect is greater in soils with low colloids and organic matter contents. 相似文献
9.
Towada Ando soils consisted of five soils—Towada-a (1,000 years old), Towada-b (2,000 years old), Chuseri (4,000 years old), Nanbu (8,600 years old), and Ninokura soils (10,000 years Amorphous clay materials of these soils taken at different localities were studied by the combined use of selective dissolution and differential infrared spectroscopy, X-ray analysis, electron microscopy, etc. The main clay minerals of Towada-a soils, present-day soils, were montmorillonite-vermic-ulite chloritic intergrades and opaline silica, or these minerals and allophane in the humus horizons, and allophane in the non-humus ones. Towada-b soils overlain by the Towada-a soils showed the clay mineralogical constituents similar to those of Towada-a soils. However, allophane was one of the main clay minerals in all the humus horizons as well as non-humus ones. The main clay minerals of Chuseri soils were allophane and layer silicates consisting chiefly of chloritic intergrades and chlorite in the humus horizons, and allophane in the non-humus ones. Opaline silica was present in minor amounts in the humus horizons of Chuseri soils, but nearly absent in Nanbu and Ninokura soils. There were remarkable differences in the clay mineralogical composition of Nanbu and Ninokura soils with differences of their environmental conditions. Allophane and imogolite Were dominant in the clay fractions of both humus and non-humus horizons of very shallowly buried Nanbu soil which was subjected to the strong leaching process. Allophane was the main clay mineral of deeply buried Nanbu and Ninokura soils which showed the absence of notable accumulation of bases and silica. On the contrary, halloysite with a small amount of siliceous amorphous material appeared in very deeply buried Nanbu and Ninokura soils where bases and silica were distinctly accumulated. The amounts of halloysite in the clay fractions were larger in the humus horizons than non-humus ones, and in Ninokura soil than Nanbu soil. Soil age, soil organic matter, and depositional overburden of tephras were observed to be conspicuous among various factors relating to the weathering of amorphous clay materials in Towada Ando soils. 相似文献
10.
Soil water availability is most essential in the Sahelian agriculture but is hampered by several factors. Surface crusts or crust-like surfaces, which are characteristic of most Sahelian soils, have been shown to decrease water infiltrability and increase runoff. Their type and structure are influenced by soil texture, vegetation cover, erosion and deposition effects of wind and water. A soil and terrain survey in semi-arid SW-Niger was carried out to explain the patterns of soil surface crusts and the deterioration of the land. The soil surface crusts were shown to depend also on specific terrain factors including land use type and intensity, and terrain type and position. Chemical and physical soil factors such as organic carbon, soil colour and texture occurring with specific crusts indicate soil degradation, especially in sloping terrain, which increases runoff and soil erosion. For sandy soils, surface tillage is required to break up the crusts. Higher surface organic matter is recommended to enhance water infiltration in soils. 相似文献
11.
In this work comparative research of the quantitative characteristics of the humus status (HS) of Estonian arable Podzoluvisols (PD) and some very closely related soils were carried out. This study was conducted to determine soil humus cover (HC) and subsoil humus content (percentage and pool) and to analyse the role of plant residues in their formation. The specific objective was to discuss the ecological factors and mechanisms which influence the flux of soil organic matter (SOM) through soils and to evaluate its contemporary status. For this purpose different databases (DB) were used: (1) DB of large-scale soil mapping (1958-78), (2) DB PEDON of pedoecological researches (1967-85), (3) DB of HS research transects (1986-91) and (4) data from two long-term field trials (1985-92). In the conditions of regular agricultural practice the mean SOM percentage in the HC of arable PD is within the range of 1.8-2.1 %, which is 0.1-0.3 units (%) the below optimal level and is in a critical state. Impoverishment is caused mainly by deep plowing. The dependence of humus retaining capacity (presumed to be a good criterion for evaluating the current HS of soils) on the mode and intensity of tillage, soil water regime, carbonate content and textural class was discussed. Mean annual inflow of organic matter into HC (4-5 Mg ha-yr?1) forms an average 5.5-6.7 % from its pool in soil. Application of manures increases this percentage to 12-13. It may be concluded that the HC might be shallower, but must be richer in humus. The annual balance of SOM reflects better than annual balance of humus, the influence of fresh SOM on the soil current year productivity. 相似文献
12.
N. A. Manucharova A. M. Yaroslavtsev A. L. Stepanov I. I. Sudnitsyn P. A. Kozhevin 《Moscow University Soil Science Bulletin》2012,67(1):25-32
It has been established that soil moisture has a significant impact on the activity of chitinolytic microbial processes, rather
than pectinolytic processes. The degradation of polysaccharides with an increase in soil moisture in microbial complex markedly
increases the role of prokaryotic microorganisms, especially actinomycetes. For the first time, using the FISH method, the
amount of detected phylogenetic composition of a metabolically active hydrolytic complex of humus horizons of grey forest
and gley and weakly podzolic soil and humus has been estimated depending on the humidity. At optimum moisture, phylogenetic
groups Actinobacteria and Firmicutes dominated in the chitinolytic process. An increase in the proportion of proteobacteria is observed with an increase in humidity.
The role of gamma- and alphaproteobacteria and actino-bacteria is heightened with the drying of soil in the hydrolytic complex.
A quantitative estimate of the rate of degradation of polysaccharides (pectin and chitin) in different types of soils at different
levels of moisture is given. The dependence of the phylogenetic composition of an active microbial hydrolytic complex of humus
horizons of grey forest and gley, weakly podzolic soils and humus on humidity is revealed. 相似文献
13.
The study of soils of different ages in different physiographic regions of the Crimean Peninsula made it possible to reveal
the main regularities of pedogenesis in the Late Holocene (in the past 2800 years). With respect to the average rate of the
development of soil humus horizons, the main types of soils in the studied region were arranged into the following sequence:
southern chernozems and dark chestnut soils > mountainous forest brown soils > gravelly cinnamonic soils. In the newly formed
soils, the accumulation of humus developed at a higher rate than the increase in the thickness of humus horizons. A sharp
decrease in the rates of development of soil humus profiles and humus accumulation took place in the soils with the age of
1100-1200 years. The possibility for assessing the impact of climate changes on the pedogenetic process on the basis of instrumental
meteorological data was shown. The potential centennial fluctuations of the climate in the Holocene determined the possibility
of pulsating shifts of soil-geographic subzones within the steppe part of the Crimea with considerable changes in the rates
of the development of soil humus horizons in comparison with those in the Late Holocene. 相似文献
14.
The method of chemodestructive fractionation is suggested to assess the composition of soil organic matter. This method is based on determination of the resilience of soil organic matter components and/or different parts of organic compounds to the impact of oxidizing agents. For this purpose, a series of solutions with similar concentration of the oxidant (K2Cr2O7), but with linearly increasing oxidative capacity was prepared. Chemodestructive fractionation showed that the portion of easily oxidizable (labile) organic matter in humus horizons of different soil types depends on the conditions of soil formation. It was maximal in hydromorphic soils of the taiga zone and minimal in automorphic soils of the dry steppe zone. The portion of easily oxidizable organic matter in arable soils increased with an increase in the rate of organic fertilizers application. The long-lasting agricultural use of soils and burying of the humus horizons within the upper one-meter layer resulted in the decreasing content of easily oxidizable organic matter. It was found that the portion of easily oxidizable organic matter decreases by the mid-summer or fall in comparison with the spring or early summer period. 相似文献
15.
E. V. Shein V. I. Kiryushin A. A. Korchagin M. A. Mazirov A. V. Dembovetskii L. I. Il’in 《Eurasian Soil Science》2017,50(10):1166-1172
Complexes of gray forest soils of different podzolization degrees with the participation of gray forest podzolized soils with the second humus horizon play a noticeable role in the soil cover patterns of Vladimir Opolie. The agronomic homogeneity and agronomic compatibility of gray forest soils in automorphic positions (“plakor” sites) were assessed on the test field of the Vladimir Agricultural Research Institute. The term “soil homogeneity” implies in our study the closeness of crop yield estimates (scores) for the soil polygons; the term “soil compatibility” implies the possibility to apply the same technologies in the same dates for different soil polygons within a field. To assess the agronomic homogeneity and compatibility of soils, the statistical analysis of the yields of test crop (oats) was performed, and the spatial distribution of the particular parameters of soil hydrothermic regime was studied. The analysis of crop yields showed their high variability: the gray forest soils on microhighs showed the minimal potential fertility, and the maximal fertility was typical of the soils with the second humus horizon in microlows. Soils also differed significantly in their hydrothermic regime, as the gray forest soils with the second humus horizon were heated and cooled slower than the background gray forest soils; their temperature had a stronger lag effect and displayed a narrower amplitude in seasonal fluctuations; and these soils were wetter during the first weeks (40 days) of the growing season. Being colder and wetter, the soils with the second humus horizons reached their physical ripeness later than the gray forest soils. Thus, the soil cover of the test plot in the automorphic position is heterogeneous; from the agronomic standpoint, its components are incompatible. 相似文献
16.
The data of two soil and vegetation surveys of flood basins of the Mamai irrigation system performed in 1987 and 2012 are compared. This irrigation system is found within the Caspian Lowland in Western Kazakhstan oblast of Kazakhstan. The thickness of the humus horizon decreased by 4 cm on the average attesting to the first-second stages of soil degradation. The humus content in the A + B1 horizons decreased by 0.3% on the average with variations corresponding to the first-third degradation stages. From 1987 to 2012, the area of saline soils and the content of exchangeable sodium in them also increased attesting to the development of desertification in the studied zone. The flooded portion of flood basins decreased from 84% in 1987 to 69% in 2012, and the groundwater level rose from 3.6–4.0 to 1.8–3.1 m. Soil degradation processes, together with adverse anthropogenic impacts, resulted in a decrease in the projective cover of valuable plant species and the productivity of herbs grown in flood basins. 相似文献
17.
Robert M. Zablotowicz Martin A. Locke Lewis A. Gaston 《Biology and Fertility of Soils》2007,44(1):27-35
This research concerns the influence of no tillage (NT) or conventional tillage (CT) and a ryegrass (Lolium multiforum Lam.) cover crop in a cotton (Gossypium hirsutum L.) production system on soil and ryegrass microbial counts, enzyme activities, and fluometuron degradation. Fluorescein
diacetate hydrolysis, aryl acylamidase, and colony-forming units (CFUs) of total bacteria and fungi, gram-negative bacteria,
and fluorescent pseudomonads were determined in soil and ryegrass samples used in the degradation study. Fluometuron (14C-labelled
herbicide) degradation was evaluated in the laboratory using soil and ryegrass. The CT and NT plots with a ryegrass cover
crop maintained greater microbial populations in the upper 2 cm compared to their respective no-cover soils, and CT soils
with ryegrass maintained greater bacterial and fungal CFUs in the 2–10 cm depth compared to the other soils The highest enzymatic
activity was found in the 0–2 cm depth of soils with ryegrass compared to their respective soils without ryegrass. Ryegrass
residues under NT maintained several hundred-fold greater CFUs than the respective underlying surface soils. Fluometuron degradation
in soil and ryegrass residues proceeded through sequential demethylation and incorporation of residues into nonextractable
components. The most rapid degradation was observed in surface (0 to 2 cm) soil from CT and NT–ryegrass plots. However, degradation
occurred more rapidly in CT compared to NT soils in the 2 to 10 cm depth. Ryegrass cover crop systems, under NT or incorporated
under CT, stimulated microbiological soil properties and promoted herbicide degradation in surface soils. 相似文献
18.
The features of ancient periglacial phenomena are widespread in landscapes lying beyond the modern permafrost zone. The specificity of the paleogeographic conditions in the south of the Baikal region resulted in the formation of paleocryogenic landscapes with hummocky-hollow landforms. The paleocryogenic mounds (hummocks) are of rounded or elongated shape, their height is up to 2–3 m, and their width is up to 20–25 m. They are separated by microlows (hollows). This paleocryogenic microtopography favors the differentiation of the pedogenesis on the mounds and in the hollows, so the soil cover pattern becomes more complicated. It is composed of polychronous soils organized in complexes with cyclic patterns. Light gray and gray forest soils and leached and ordinary chernozems are developed on the mounds; gray and dark gray forest soils and chernozems with buried horizons are developed in the hollows. The soils of the paleocryogenic complexes differ from one another in their morphology, physical and chemical properties, elemental composition, and humus composition. For the first time, radiocarbon dates have been obtained for the surface and buried humus horizons in the hollows. The results prove the heterochronous nature of the soils of the paleocryogenic landscapes in the south of the Baikal region. 相似文献
19.
A. M. Prokashev 《Eurasian Soil Science》2012,45(11):1013-1022
A plowed soddy-calcareous soil with relict features developed from Permian clayey calcareous soil was described for the first time in the area of soddy-podzolic and gray forest soils of mixed forests in the middle and lower riches of the Vyatka River. This soil was thoroughly examined by physical, chemical, biochemical, radioisotope, and physicochemical methods. A second humus horizon enriched in calcium humates was described in this soil. Its age was determined at about 7200 yrs. This horizon attests to the presence of in situ postcarbonate pedorelicts in the soil cover of the eastern Russian Plain. The studied soil was formed during the Atlantic optimum of the Holocene under conditions more favorable to humus-accumulative processes as compared with those during the subsequent period. The soil evolution in the second part of the Holocene was characterized by the partial preservation of the previously formed features with the development of eluviation features under colder and wetter climatic conditions. This intrazonal soil is genetically close to gray forest and soddy-podzolic soils with residual second humus horizons that are widespread on the Vyatka-Kama interfluve. The evolution of the latter soils in the second part of the Holocene has been driven by eluviation processes that gradually eliminate the features of the second humus horizon from the soil profiles. 相似文献
20.
The concepts and classifications of humus forms developed since the time of scientific pedology formation are critically discussed. The concept of humus forms (types) relates to the classification of a set of topsoil organic and organomineral horizons, which reflects morphologically distinct phases of plant litter and soil organic matter decomposition, but not to the fractions of soil organic matter. Humus forms reflect various types of transformation and accumulation of organic matter in the soil. The stages of development and modern classifications of humus forms abroad are described. The taxonomy of humus forms in Russian literature and its application for the mapping and evaluation of forest soils are considered, as well as its use for the mathematical simulation of soil organic matter mineralization and humification. Prospects for the development of the classification of humus forms in combination with the basic soil classification of European Russia are discussed. A call for an understanding and a common language in soil science at the international level is underlined. 相似文献