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1.
The structural state of modern and buried chestnut soils on the Privolzhskaya Upland (Volgograd oblast) was studied in order to determine changes in the soil structure in dependence on the time of soil burying. The soils buried 3500, 1700, and 700 years ago and modern background chestnut soils were examined. The structural state of soils was determined via their fractionation on a set of sieves (10–0.25 mm) in the air-dry state. We determined the contents of coarse aggregates, total aggregates, disperse soil matter, aggregation coefficient, and the degree of differentiation of the soil profiles. It was found that the structure of buried soils is preserved for 3500 years after the soil burying. The structural state of the studied soils changed with time depending on the climatic conditions that existed at the moment of soil burying. In humid periods, the amount of coarse aggregates (lumps) decreased, and the content of aggregated fractions increased; the reverse processes took place in arid epochs. Thus, it was shown that the aggregate composition of soils is specific for each period of soil formation and depends on the degree of climatic humidity. It is preserved in the buried soils independently on the duration of their existence in the buried state. We determined the impact of aggregate size on the Corg tolerance toward mineralization processes. It was shown that the content of organic carbon and its physical protection from mineralization are determined by different mechanisms of its fixing in aggregates of different sizes and depend on the conditions for the development of soil structure before burying and on the duration of the soil existence in the buried state. The results obtained in this study can be used as a retrospective basis for predicting changes in the physical properties of soils under conditions of changing climate. 相似文献
2.
N. N. Kashirskaya T. E. Khomutova T. S. Demkina V. A. Demkin 《Eurasian Soil Science》2009,42(5):536-542
The total microbial biomass (TMB) was assessed in the chestnut and light chestnut soils and in the paleosols under burial mounds (steppe kurgans) in the Lower Volga region on the basis of data on the organic carbon content in the extracted microbial fraction supplemented with the data on the extraction completeness as a conversion coefficient. The completeness of the microbial fraction extraction was determined by direct counting of the microbial cells and colony-forming units (on plates with soil agar). The total microbial biomass varied from 400 to 6600 μg of C/soil. Its values in the buried soils were 3–5 times lower than those in the surface soils. The TMB distribution in the buried chestnut soil profile was close to that in its modern analogue (with the minimum in the B1 horizon). In the buried light chestnut paleosols, the TMB values usually increased down the profile; in the recent light chestnut soils, the maximum TMB values were found in the uppermost horizon. 相似文献
3.
Modern light chestnut and chestnut soils and their analogues buried under steppe kurgans in the southeastern part of the Russian
Plain were studied in order to determine the rates of the CO2 production by these soils under the native (with the natural moisture content) and moistened (60% of the total water capacity)
conditions. It was found that the rates of the CO2 production by the soil samples in the native state are relatively close to one another and vary from 0.3 to 1.4 μg of C/100
g of soil/h. The rates of the CO2 production in the moistened state increased by two orders of magnitude for the modern surface soils and by an order of magnitude
for the buried soils. 相似文献
4.
A comparative analysis of the state of microbial communities in kurgans, paleosols buried under them, and background surface soils in the dry steppe zone of the Lower Volga region has been performed. It is shown that the population density of microorganisms of various trophic groups in the kurgans is an order of magnitude lower than that in the A1 horizon of the corresponding buried paleosols and background surface soils within the areas of chestnut, light chestnut, and solonetzic soils. The respiration activity of the microbial communities in the upper layer of the kurgans is comparable with that in the A1 horizons of the background surface soils; it decreases in the deeper layers of the kurgans. In the A1 horizon of the buried paleosols, the respiration activity is approximately the same as in the deep layers of the kurgans. In the buried paleosols, the spatial variability in the numbers of soil microorganisms is approximately the same or somewhat higher than that in the background surface soils. The spatial variability in the respiration activity of the buried paleosols is two to four times higher than that in the background surface soils. 相似文献
5.
Changes in the properties of soils in a solonetz soil complex thirty years after reclamation 总被引：1，自引：0，他引：1
V. P. Kalinichenko V. K. Sharshak S. F. Mironchenko V. V. Chernenko E. P. Ladan E. D. Genev V. V. Illarionov A. V. Udalov V. V. Udalov E. V. Kippel 《Eurasian Soil Science》2014,47(4):319-333
The long-term (30 year) dynamics of a solonetz soil complex composed of solonetzic light chestnut soils and chestnut solonetzes under standard conditions and with the application of agromeliorative measures are considered. When the standard zonal agricultural practice is used, the soils of the solonetzic complex have unfavorable agrophysical, chemical, and physicochemical properties and low productivity. After 30 years of the standard three-level tillage of the soils to a depth of 40–45 cm, the productivity of the biogeocenosis decreased. Thirty years after a single rotary-milling subsoil treatment of the 20- to 45-cm soil layer using a milling tool FS-1.3, there were no morphological features pointing to the restoration of the solonetzic process. The humus content in the 0-to 20-cm and 20-to 40-cm soil layers was 2.3 and 1.7%, respectively; the content of adsorbed Na+ in the 20-to 30-cm layer was 11.6% of the total exchange capacity, or 38% lower than its content in the reference soil. The additional yield reached 30–70% and more of that obtained with the standard agricultural technology used during the whole period under investigation. The method of systems biogeotechnology (systems bio-geo engineering) is proposed as a method for the preventive control of soil evolution and the maintenance of the stability and high productivity of the soil cover. 相似文献
6.
The microbial communities were studied in the modern and buried under kurgans (1st century AD) soils of solonetzic complexes on the dry steppes of the northern part of the Yergeni Upland. It was found that the changes in the numbers of microorganisms from different trophic groups and in the biomass of the fungal mycelium along the profiles of the modern and buried solonetzic chestnut soils and solonetzes do not differ significantly. The quantitative estimate of the impact of the solonetzic process on the spatial variability of the microbiological parameters of the soils was given on the basis of the ANOVA. As a rule, the values of the microbiological parameters in all the horizons of the modern and buried chestnut soils were 1.2–2.8 times higher than those in the modern and buried solonetzes. The influence of the degree of solonetzicity of the buried paleosols on the microbiological parameters manifested itself in the entire profile, though in each particular horizon it was only seen in the numbers of some particular trophic groups of microorganisms. The comparison between the mean weighted values of the microbiological parameters in the entire soil profiles (the A1 + B1 + B2 horizons) demonstrated an inverse relationship between the population density of the microorganisms utilizing easily available organic matter and the degree of solonetzicity of the buried paleosols. The maximum biomass of the fungal mycelium was found in the solonetzic chestnut paleosol; it exceeded the biomass of the fungal mycelium in the other paleosols (which did not differ significantly in that parameter from one another) by 1.5–1.6 times. 相似文献
7.
The contents of phospholipids and carbon of the total microbial biomass were determined in the modern chestnut soil and in
the paleosols buried under mounds of the Bronze and Early Iron Ages (5000–1800 years ago) in the dry steppe of the Lower Volga
River basin. Judging from data on the ratio between the contents of phospholipids and organic carbon in the microbial cells,
the carbon content of the living microbial biomass was calculated and compared with the total microbial biomass and total
organic carbon in the studied soils. In the background chestnut soil, the content of phospholipids in the A1, B1, and B2 horizons
amounted to 452, 205, and 189 nmol/g, respectively; in the paleosols, it was 28–130% of the present-day level. The maximum
content was measured in the paleosols buried 5000 and 2000 years ago, in the periods with an increased humidity of the climate.
In the background chestnut soil, the total microbial biomass was estimated at 5680 (the A1 horizon), 3380 (B1), and 4250 (B2)
μg C/g; in the paleosols, it was by 2.5–7.0 times lower. In the upper horizons of the background soil, the portion of the
living microbial biomass in the total biomass was much less than that in the paleosols under the burial mounds; it varied
within 8.5–15.3% and 15–81%, respectively. The portion of living microbial biomass in the total organic carbon content of
the background chestnut soil was about 4–8%. In the paleosols buried in the Early Iron Age (2000 and 1800 years ago), this
value did not exceed 3–8%; in the paleosols of the Bronze Age (5000–4000 years ago), it reached 40% of the total organic carbon. 相似文献
8.
V. P. Kalinichenko V. K. Sharshak O. S. Bezuglova E. P. Ladan E. D. Genev V. V. Illarionov V. E. Zinchenko N. A. Morkovskoi V. V. Chernenko L. P. Il’ina 《Eurasian Soil Science》2011,44(8):927-938
Changes in the properties of solonetzic soil associations (chestnut solonetzic soils and chestnut solonetzes) in the dry steppe
after their reclamation have been studied for 30 years. The reclamation included the deep three-tier plowing and the approach
of rotary tillage. A single rotary tillage operation resulted in the formation of fine aggregates of equal sizes in the plow
layer; any morphological features of the restoration of solonetzic pedogenesis are absent. The atmospheric moisture easily
penetrates into the soil, and soluble salts are leached off to a great depth. In 30 years since the soil amelioration with
the use of a PMS-70 rotary tiller, the humus content has increased up to 3.3% in the upper 20-cm-thick layer and up to 2.4%
in the layer of 20–40 cm. The content of adsorbed Na+ in the 20- to 30-cm-thick layer has decreased to 10.6% of the cation exchange capacity (in comparison with 19.8% in the nonreclaimed
soil). The spatial heterogeneity of the soil cover has decreased in comparison with that prior to the reclamation. During
the entire observation period, crop yields gained from the fields reclaimed with the use of the rotary tiller have been by
25–60% higher in comparison with those on the fields with traditional treatments. 相似文献
9.
Gypsum application was highly efficient as a treatment for reducing amounts of exchangeable sodium and inhibiting clay dispersion in highly structured saline-sodic clay topsoils. Phosphogypsum, applied to the surfaces of aggregates in soil columns treated with simulated rainfall, was dissolved efficiently by frequent intermittent ‘rainfall’. The calcium released by dissolution displaced sodium on the exchange complex within soil aggregates ranging from 7.5 mm to 45 mm in diameter. Of the applied calcium, 64–74% was transferred to ion exchange sites; however, almost one-third of this adsorbed calcium displaced exchangeable magnesium. Comparison of three gypsum treatments, phosphogypsum, rock gypsum, and a saturated gypsum solution (representing a top dressing of highly soluble gypsum), showed that the effectiveness of calcium uptake on the exchange complex followed the order: rock gypsum < saturated solution < phosphogypsum, but differences were small. Application of phosphogypsum caused a 90% reduction in the total amount of dispersed clay released in column leachates, and decreased the maximum clay concentration in the effluents by at least 80%, when compared to soils leached without gypsum treatment. 相似文献
10.
Khomutova T. E. Kashirskaya N. N. Demkina T. S. Borisov A. V. Stretovich I. V. Demkin V. A. 《Eurasian Soil Science》2006,39(1):S112-S117
The contents of carbon in the total microbial biomass (C-TMB) and in the microorganisms reactivated with glucose (C-RG) and the portion of glucose-reactivated microorganisms in the microbial community (C-RG/C-TMB) were determined in paleosols buried under desert-steppe kurgans (burial mounds) 5100–3960 years ago and in the background surface light chestnut soils. In the paleosols, the corresponding indices reached 986 μg/g (C-TMB), 14.6 μg/g (C-RG), and 1.5% (C-RG/C-TMB) and were considerably lower than those in the background surface soil. The lowest values were found for the paleosols buried 4260–3960 years ago, which confirms a conclusion about the paleoecological crisis during this time interval. 相似文献
11.
12.
以不同土地利用方式下（疏林荒草地、荒草地、林地和耕地）第四纪古红土和埋藏第四纪古红土剖面为研究对象,测定古红土各发生层全土及各粒级团聚体的有机碳含量,比较不同土地利用方式下第四纪古红土剖面及团聚体的有机碳分布特征。结果表明:（1）埋藏古红土有机碳含量较低,随深度分布均一,各粒级团聚体内有机碳含量随团聚体粒径减小而降低;（2）埋藏古红土出露地表后,由于受到人为活动影响,表层全土有机碳及各粒级团聚体有机碳含量均增加,呈现林地 > 耕地 > 疏林荒草地 > 荒草地 > 埋藏古红土的特征,其中,林地显著高于其他土地利用方式,说明林地是古红土分布区的一种较合理的土地利用方式;（3）耕地0 ~ 10 cm土层粒径 > 1 mm和 < 0.25 mm团聚体的有机碳含量均随团聚体粒径减小而逐渐增加,1 ~ 0.25 mm团聚体有机碳含量随团聚体粒径减小逐渐降低。其余土地利用方式下古红土均呈现 > 0.25 mm团聚体的有机碳含量随着团聚体粒径减小而逐渐降低,< 0.25 mm团聚体的有机碳含量随团聚体粒径减小而逐渐增加。 相似文献
13.
D. I. Eremin 《Eurasian Soil Science》2016,49(5):538-545
The results of long-term studies of changes in the content and fractional-group composition of humus in leached chernozems (Luvic Voronic Chernozems, WRB 2006) of the Trans-Ural forest-steppe since the beginning of their plowing are considered. These soils are characterized by the high humus pool (up to 500 t/ha in the virgin state and up to 430 t/ha in the plowed state) and the high degree of the organic matter humification. Humus is of the fulvate–humate type in the upper 30 cm and of the humate–fulvate type in the deeper layers. From 1968 to 2006, the total pool of humus in the 1-m-deep soil layer of the plowed chernozems decreased by 8.5% in comparison with the initial virgin soils. The rate of dehumification reached 1.0–1.4 t/ha per year. The long-term plowing of leached chernozems also led to a smaller content of nitrogen in the organic matter (the C/N ratio increased from 11.5 to 13.6). The relative content of free humic acids (HA-1) and humic acids bound to clay minerals (HA-3) increased, whereas the content of calcium humates (HA-2) decreased. The composition of fulvic acids in the plow horizon was characterized by the rise in the content of aggressive (FA-1a) and mobile (FA-1) fractions, while the amount of fulvates bound to calcium (FA-2) decreased. 相似文献
14.
American chestnut trees once dominated vast areas of deciduous forest in eastern North America, but the exotic chestnut blight almost eliminated the species from the region. Introduction of blight-resistant American chestnut hybrids will probably start in the next decade after many years of tree breeding. What were the historic effects of chestnut on forest soils, and what changes may follow reintroduction of hybrid chestnuts? A site in southern Wisconsin provided an opportunity to examine the effect of chestnut trees on soil properties. At this site, 600 km northwest of chestnut's historic distribution, naturalized chestnuts have spread throughout an intact mixed-species forest from nine planted trees. The site contains soil developed on a silty loess-mantled ridge that abuts sandier hillslopes, allowing the effects of individual chestnuts to be examined on two soil types. I sampled and analyzed forest floor and mineral soils beneath canopies of individual American chestnuts and the surrounding mixed-species deciduous forest on fine-silt and sandy-loam soil types. On sandy loam soils, total soil carbon (C) and nitrogen (N), inorganic N and net mineralization and nitrification rates were 10–17% higher beneath chestnut canopies compared to soils beneath mixed-species deciduous forest. The pool of total soil N beneath chestnut canopies was positively related to the silt content of the sandy loam soils. In contrast, there were no differences between properties of chestnut canopy and mixed-species deciduous forest soils on the fine silt texture class. On sandy loam soil conditions common throughout the pre-blight distribution of American chestnut, soil biogeochemical processes differ beneath individual chestnut trees relative to a diverse mixture of deciduous species. These findings suggest that widespread chestnut reintroduction has the potential to alter both stand- and watershed-scale processes. 相似文献
15.
Forms of heavy metal compounds in soils of the steppe zone 总被引：1，自引：0，他引：1
T. M. Minkina G. V. Motuzova O. G. Nazarenko V. S. Kryshchenko S. S. Mandzhieva 《Eurasian Soil Science》2008,41(7):708-716
A parallel scheme of extractions was used for determining heavy metal compounds in uncontaminated and artificially contaminated soils of Rostov oblast. A method for calculating the contents of complex and specifically adsorbed metal compounds from the difference in their concentrations in different extracts was suggested. It was found that the portion of firmly fixed metal compounds decreases and the portion of potentially mobile (exchangeable, complex, and specifically adsorbed) metal compounds increases with an increase in the degree of contamination of chernozems and chestnut soils with lead, copper, and zinc over a one-to two-year-long observation period. This was due to the capacity of heavy metal ions to substitute for the exchangeable cations in the exchange complex of the studied soils, to form complexes with the soil organic matter, and to participate in the specific adsorption. Some differences in the behavior of different metals were found. 相似文献
16.
N. N. Kashirskaya T. E. Khomutova V. V. Dmitriev V. I. Duda N. E. Suzina V. A. Demkin 《Eurasian Soil Science》2010,43(10):1140-1149
The morphology of microbial cells was studied, and the biomass of microorganisms was estimated in the modern steppe soils
and paleosols buried under kurgans in the Lower Volga region with the methods of electron microscopy. The shape and ultrastructure
of the cells in the modern soils and paleosols were similar, though their average volumes differed (0.37 and 0.28 μm3, respectively). The portion of cells with a volume above 1 μm3 in the surface soils and paleosols reached 10.9 and 9.2%, respectively, and the portion of cells with a volume less than
0.01 μm3 in the surface soils was 10% lower than that in the buried paleosols. It was found that the cells of the microorganisms have
an external organomineral layer, which increases the cell volume by 4.9 times, and this fact was taken into account in the
calculation of the microbial biomass. In the chestnut and light chestnut paleosols, the latter comprised 1500 and 230 μg of
C/g soil, respectively. 相似文献
17.
V. M. Semenov L. A. Ivannikova T. V. Kuznetsova N. A. Semenova A. S. Tulina 《Eurasian Soil Science》2008,41(7):717-730
The susceptibility of soil organic matter (SOM) to mineralization decreases in the following sequence of zonal soils: tundra soil > soddy-podzolic soil > gray forest soil > chestnut soil > dark chestnut soil > chernozem. The content of potentially mineralizable organic matter in the plowed soils is 1.9–3.9 times lower than that in their virgin analogues. The highest soil carbon sequestration capacity (SCSC) is typical of the leached chernozems, and the lowest SCSC is typical of the tundra soil. Taking into account the real soil temperatures and the duration of the warm season, the SCSC values decrease in the following sequence: leached chernozem > dark chestnut soil > chestnut soil ≥ tundra soil > gray forest soil > soddy-podzolic soil. Arable soils are characterized by higher SCSC values in comparison with their virgin analogues. 相似文献
18.
Traditional chemical methods and 13C-NMR spectroscopy were used to study the humus in chestnut paleosols buried under kurgans of different ages (the 16th–15th centuries BC; the 1st, 2nd–3rd, and 13th–14th centuries AD) and under the Anna Ioanovna Rampart (1718–1720) and in their recent analogues on virgin plots. It was found that the decrease in the humus content of the paleosols as a result of the diagenetic processes is exponentially related to the age of the soil burial. The loss of humus from the upper 30 cm of the paleosol buried 3500 yrs ago amounted to 76 ± 14%, and this system did not reach a stationary state. The constants of the humus mineralization in the paleosols were determined. A tendency for an increase in the degree of the organic matter humification in the chestnut soils during the past 3500 yrs was found. With an increase in the age of the burial, the portion of aromatic structures in the structure of the humic acids increased and the portion of aliphatic fragments decreased. The cyclic changes in the composition of the humus related to the secular variations in the climatic humidity were identified. 相似文献
19.
河北省土壤硫含量、形态与分布 总被引：15，自引：1，他引：15
对河北省主要土壤类型耕层硫含量进行了分析测定。结果表明 ,河北省土壤全硫平均含量为 250.1mg/kg(50～940mg/kg)。土壤全硫平均含量以沼泽土最高 ,灰色森林土最低 ;土壤有效硫平均含量为 46.1mg/kg ,以沼泽土最高 ,红粘土和栗褐土最低。土壤硫主要以有机态存在 ,占全硫含量的 81.6% ;无机态硫占 18.4%。按土类划分土壤无机硫含量最高的是沼泽土 ,灰色森林土最低 ;土壤有机硫含量也以沼泽土最高 ,灰色森林土最低。土壤全硫含量主要受土壤有机质含量、阳离子代换量和土壤碳酸钙含量的影响。根据土壤硫供应水平计算 ,全省约有20.4%的土壤缺硫 ,北部缺硫面积较大 ,南部缺硫面积较小。根据土壤有效硫含量多寡 ,可把全省土壤硫含量划分为极缺乏区、缺乏区、中等区、丰富区及极丰富区 5类 相似文献
20.
V. A. Demkin A. V. Borisov T. S. Demkina T. E. Khomutova N. N. Kashirskaya 《Eurasian Soil Science》2010,43(13):1515-1526
On the basis of studies of subkurgan pedochronoseries, the main mechanisms of the development of soils of arid and desert
steppes in drained landscapes of the southeastern Russian plain in the Late Eneolithic and Bronze ages (6000−3000 years ago)
were established. During the fourth to third millennia BC, evolution of soils took place at the level of subtypes with a shift
of boundaries of soil subzones toward the north. In each of the studied natural regions (Central Russian Upland, Volga Upland,
Ergeni Hills, and Caspian Depression), an increase in the aridization of the climate in the second half of the third millennium
BC can be distinctly traced, owing to which a convergence of the topsoil with the transformation of dark-chestnut, chestnut,
and light-chestnut soils in chestnut-like semiarid soils, which dominated the region 4200–3900 years ago, occurred. In the
first half of the second millennium BC, another change in the conditions of soil formation occurred that was caused by an
increase in the degree of atmospheric humidity. It induced the divergence of the topsoil with a secondary formation of areas
of zonal chestnut soils and solonetzes in place of chestnut-like soils by the middle of the second millennium BC. The obtained
data gives reason to suggest that the age of modern chestnut solonetz complexes of the region does not exceed 3500 years. 相似文献