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1.
The distribution of the fungal biomass and diversity of cultivated microscopic fungi in the profiles of some soils from East (Progress Station, valleys of the Larsemann Hills oasis) and West (Russkaya Station, the Marie Byrd Land) Antarctica regions were studied. The structure of the biomass (spore/mycelium and live cells/dead cells) was analyzed by fluorescence microscopy with staining using a set of coloring agents: calcofluor white, ethidium bromide, and fluorescein diacetate. The species composition of the cultivated microscopic fungi was determined on Czapek’s medium. The fungal biomass in the soils studied is not high (on the average, 0.3 mg/g of soil); the greatest biomass (0.6 mg/g) was found in the soil samples with plant residues. The fungal biomass is mainly (to 70%) represented by small (to 2.5 μm) spores. About half of the fungal biomass is composed of living cells. There are differences in the distribution of the fungal biomass within the profiles of different primitive soils. In the soil samples taken under mosses and lichens, the maximal biomass was registered in the top soil horizons. In the soils with the peat horizon under stone pavements, the greatest fungal biomass was registered in the subsurface horizons. Thirty-eight species of cultivated microscopic fungi were isolated from the soils studied. Species of the genus Penicillium and Phoma herbarum predominated.  相似文献   

2.
The humus characteristics in buried Holocene and Late Pleistocene paleosols of the tundra zone have been studied. It is shown that the paleosol sequences encompassing the time span from 55 to 2.5 ka BP contain paleosols with analogous types of humus, attesting to the cyclic repeatability of the corresponding stages of soil formation. A tendency for an increase in the degree of humification in the course of soil development has been revealed. Within the ultracontinental areas of East Siberia, the accumulation of salts accompanied soil formation in the Late Pleistocene and Holocene.  相似文献   

3.
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   

4.
The development of forest-steppe and steppe chernozems on the Dniester-Prut interfluve in the Holocene was studied on the basis of data on the paleosols buried under archaeological monuments of different ages. The parameters of the mathematic models of the development of the soil humus horizons in different subtypes of chernozems were calculated. They were used to determine the rate of this process and the age of the soils formed on the surface of Trajan’s lower rampart. The climate-controlled changes in the character of the soil’s development in the Late Holocene were differently pronounced in the different subtypes of chernozems. The suggested differentiation of the trends in the development of the humus horizon in the studied chernozems corresponds to the differences in the soil-forming potential of particular areas (as judged from the energy consumption for pedogenesis).  相似文献   

5.
The size, number, and biomass of bacteria and microscopic fungi were studied in chernozems of different land uses (forest, fallow, pasture, and cropland), in paleosols under mounds of different ages in the territories adjacent to the background recent chernozems; and in the cultural layer of an ancient settlement of the Bronze Age, Early Iron Age, and Early Middle Age (4100–1050 years ago). The method of cascade filtration revealed that bacterial cells had a diameter from 0.1 to 1.85 μm; their average volume varied from 0.2 to 1.1 μm3. Large bacterial cells predominated in the soils of natural biocenoses; fine cells were dominants in the arable soils and their ancient analogues. The bacterial biomass counted by the method of cascade filtration was first found to be 10–380 times greater than that determined by luminescence microscopy. The maximal bacterial biomass (350–700 μg/g) was found in the soils of the birch forest edge (~80-year-old) and under the 80-year-old fallow. In the soils of the 15–20 year-old fallows and pastures, the bacterial biomass was 110–180 μg/g; in the arable soils and soils under the mounds, it was 80–130 and 30–130 μg/g, respectively. The same sequence was recorded in soils for the content of fungal mycelium and spores, which predominated over the bacterial mass. With the increasing age of the buried paleosols from 1100 to 3900 years, the share of the biomass of fungal spores increased in the total fungal and total microbial biomasses. In the cultural layer of the Berezovaya Luka (Altai region) settlement that had been functioning about 4000 years ago, the maximal biomass and number of fungal spores and the average biomass of bacteria and fungal mycelium comparable to that in the studied soils were revealed. In this cultural layer, the organic matter content was low (Corg, 0.4%), and the content of available phosphorus was high (P2O5, 17 mg/g). These facts attest to the significant saturation of this layer with microbial cenoses 4000 years ago and to their partial preservation up to now owing to the high concentration of ancient human wastes there.  相似文献   

6.
The difference between the mycobiota in anthropogenically transformed soils of the settlements of the 9th–14th centuries and in the background zonal Podzols and umbric Albeluvisols of the middle and southern taiga subzones in the European part of Russia is demonstrated. The mycological specificity of anthropogenically transformed soils with a cultural layer (CL) in comparison with the background soils is similar for all the studied objects. Its characteristic features are as follows: (1) the redistribution of the fungal biomass in the profile of anthropogenically transformed soils in comparison with zonal soils, (2) the lower amount of fungal mycelium in the CL with the accumulation of fungal spores in this layer, (3) the increased species diversity of fungal communities in the CL manifested by the greater morphological diversity of the spore pool and by the greater diversity of the fungi grown on nutrient media, (4) the change in the composition and species structure of fungal communities in the CL, (5) the replacement of dominant species typical of the zonal soils by eurytopic species, and (6) the significant difference between the fungal communities in the CL and in the above-and lower-lying horizons and buried soils of the same age. Most of the mycological properties of the soils of ancient settlements are also typical of modern urban soils. Thus, the mycological properties of soils can be considered informative carriers of soil memory about ancient anthropogenic impacts.  相似文献   

7.
Chemical and optical characteristics of soil humus have been analyzed as “memory” components of the Pleistocene volcanic paleosols in Mexico. We have studied the A1 horizons of buried Andosols of the Nevado de Toluca series and of the modern Andosols formed under different bioclimatic conditions. Data on the organic matter of buried paleosols suggest that Andosols of the Nevado de Toluca series were formed in humid forest ecosystems. Optical characteristics of the humic acids and data on the molecular-mass distribution of the humus make it possible to assume that these soils were formed under pine forests rather than under fir forests.  相似文献   

8.
Eurasian Soil Science - Results of the study of humus composition in about 200 modern soils of different genesis and more than 100 buried Pleistocene and Holocene paleosols have been collected and...  相似文献   

9.
The soil evolution in the depression of Lake Nero was driven by climate changes in the Holocene and by the history of the relief’s development in this region. In the Alleröd period, dark-colored soils were formed; in the Late Dryas period, they were cryoturbated and covered by colluvial deposits from the adjacent slopes. These specific paleosols are found on relatively high ancient surfaces. In the Early and Middle Holocene (10000–3700 BP), dark-colored horizons of soils with high stability of the organic matter were formed. The properties of humus in these soils are close to the properties of humus in forest-steppe soils. In the past 3500–3700 years, under conditions of some cooling and humidization of the climate with the development of taiga pedogenesis, these soils have evolved into soddy-podzolic soils. Their dark-colored horizons have degraded, though their lower parts are partly preserved in many places as the second humus horizons, the most distinctive feature of the soil polygenesis in the studied region. The soils of the low terrace (100–103 m a.s.l.) are younger than the soils of the higher and more ancient surfaces. Their evolution followed the same stages, though the Alleröd paleosols have not been found on this surface. In the coastal zone, at the heights below 97 m a.s.l., the soil formation began later, about 7000 years ago. Afterwards, the soils of this surface were subjected to the influence of fluctuations in the lake’s level. During the regression phase (7000–3500 BP), which corresponded to the dark-colored pedogenesis, these soils and the habitation deposits of the Bronze Age were formed on the dried bottom of the lake below its modern lake level of 93.2 m a.s.l. In the Late Holocene, these soils in the coastal zone were subjected to waterlogging rather than to podzolization due to the rise in the lake’s level; they have evolved into the soddy gley soils.  相似文献   

10.
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   

11.
Mycelial fungi in a solonchakous chestnut soil, a sulfate solonchak, and a soda solonchak were studied in the western Lake Baikal basin. The humus content, the degree of salinization, and the composition of salts affected the structure of the micromycete communities. In the chestnut soil, more than half of the species identified were found. The species diversity was higher in the nonsaline and humus horizons. The eolian deposit on the soda solonchak was characterized by the presence of six species of fungi that did not occur in other soil horizons. Their occurrence in the fresh deposit seems to be related to the eolian transfer of fungi with the fine earth from the adjacent areas with the nonsaline soils. The soda solonchak fungi are dominated by the haloalkalitolerant and alkalophilic micromycetes, among which the representatives of the Acremonium (A. antarcticum and A. rutilum) and Verticillum genera and Mycelia sterilia were identified. There was also an alkalophilic ascomycete, which is an indicator of soda salinization??Heleococcum alkalinum. On the whole, the soda solonchak had the lowest number of fungal germs and the lowest species diversity of mycelial fungi among the soils compared.  相似文献   

12.
Buried Late Holocene paleosols of the Nienshants historical monument at the junction of the Neva and Okhta rivers (St. Petersburg) have been studied. These soils developed from estuary deposits of the Littorina basin with abundant artifacts of the Neolithic and Early Iron ages (7–2 ka BP). The soil cover of the area consists of the mature dark-humus profile-gleyed soils on elevated elements of the mesotopography (3.0–3.5 a.s.l.) and dark-humus gley soils in the local depressions (2.0–2.6 m a.s.l.). The soils are characterized by the low to moderate content of humus of the fulvate-humate type. The beginning of humus formation in the dark-humus gley soil on the slope facing the Neva River is estimated at about 2600 yrs ago; for the darkhumus profile-gleyed soils of the studied paleocatena, at about 2000 and 1780 yrs ago; and for the darkhumus gley soil, at about 1440 years ago. Judging from the spore-pollen spectra, the development of these soils took place in the Subatlantic period under birch and pine-birch forests with the admixture of spruce and alder trees. The gleyed horizons of the buried soil at the depth of 1.6–1.2 m on the Neva-facing slope date back to the Late Subboreal period (2500–2600 yrs ago), when pine-birch-spruce forests were widespread in the area. The new data contribute to our knowledge of the environmental conditions during the Neolithic and Iron ages.  相似文献   

13.
Borisov  A. V.  Ganchak  T. V.  Demkina  T. S.  Demkin  V. A. 《Eurasian Soil Science》2006,39(1):S106-S111
The contents of fungal mycelium have been studied in paleosols of ancient archeological monuments and in surface soils within the steppe, dry steppe, and desert zones of European Russia, on the Stavropol, Privolzhskaya, and Ergeni uplands. The buried paleosols date back to the Bronze Age (4600–4500 and 4000–3900 BP), the Early Iron Age (1900–1800 BP), and the early 18th century (1719–1721). The fungal mycelium has been found in all these paleosols. The biomass of fungal mycelium varies from 2 to 124 μg/g of soil. The distribution patterns of fungal mycelium in the profiles of buried paleosols and surface soils have been identified. It is shown that the dark-colored mycelium is typical of the ancient paleosols. In some cases, the content of the dark-colored mycelium in them may reach 100% of the total mycelium biomass.  相似文献   

14.
The number, biomass, length of fungal mycelium, and species diversity of microscopic fungi have been studied in soils of the tundra and taiga zones in the northern part of the Kola Peninsula: Al-Fe-humus podzols (Albic Podzols), podburs (Entic Podzols), dry peaty soils (Folic Histosols), low-moor peat soils (Sapric Histosols), and soils of frost bare spots (Cryosols). The number of cultivated microscopic fungi in tundra soils varied from 8 to 328 thousand CFU/g, their biomass averaged 1.81 ± 0.19 mg/g, and the length of fungal mycelium averaged 245 ± 25 m/g. The number of micromycetes in taiga soils varied from 80 to 350 thousand CFU/g, the number of fungal propagules in some years reached 600 thousand CFU/g; the fungal biomass varied from 0.23 to 6.2 mg/g, and the length of fungal mycelium varied from 32 to 3900 m/g. Overall, 36 species of fungi belonging to 16 genera, 13 families, and 8 orders were isolated from tundra soils. The species diversity of microscopic fungi in taiga soils was significantly higher: 87 species belonging to 31 genera, 21 families, and 11 orders. Fungi from the Penicillium genus predominated in both natural zones and constituted 38–50% of the total number of isolated species. The soils of tundra and taiga zones were characterized by their own complexes of micromycetes; the similarity of their species composition was about 40%. In soils of the tundra zone, Mortierella longicollis, Penicillium melinii, P. raistrickii, and P. simplicissimum predominated; dominant fungal species in soils of the taiga zone were represented by M. longicollis, P. decumbens, P. implicatum, and Umbelopsis isabellina.  相似文献   

15.
Paleosol studies of archaeological monuments of different ages have been conducted on the Transural Plateau. The morphological and physicochemical properties of paleosols under burial mounds (kurgans) of the Early Iron Age (the fifth and fourth centuries BC) were compared with the properties of background surface soils. A paleosol of the Savromat epoch (2500 BP) is characterized by high contents of gypsum and soluble salts. The presence of humus tongues in its profile attests to the aridity and continentality of the climatic conditions during that epoch. Paleosols buried under kurgans of the Late Sarmatian epoch and the Hun epoch (about 1600 BP) are characterized by a higher content of humus and greater depth of the carbonate horizon, which attests to the humidization of climatic conditions. The evolution of soils as related to climate dynamics in the first millennium BC and the first millennium AD is characterized.  相似文献   

16.
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   

17.
The difference between fungal communities in the cultural layer of a medieval settlement and in the background soddy calcareous soil is shown. In the cultural layer, the portion of spores, especially large spores (d > 6 μm), in the total fungal biomass is increased, whereas the portion of mycelium, especially with a thickness of > 4 μm, is decreased. The species composition of micromycetes in the cultural layer is also transformed; species from the Aspergillus and Fusarium genera predominate. The frequency and diversity of Penicillium representatives decreases, whereas the fungal species from the Phoma, Doratomyces, Geomyces, and Verticillium genera, which are not typical of the background soil horizons, increases. The diversity of the minor fungal species also increases in the cultural layer. An increased content of keratin-decomposing soil fungi is found in the cultural layer. It is argued that the use of the entire set of these characteristics makes it possible to perform mycological indication of the parts of the cultural layer that served different purposes (ancient streets, house floors, backing of the walls, etc.) within the settlement.  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.
In the organic horizons of the Al-Fe-humus podzols under the old pine forests of the northern taiga, the biomass of all the groups of microorganisms, the length of the fungal and actinomycete mycelium, the number of fungal spores, and the bacterial population were maximal (13 mg/g) irrespectively of the stage of pyrogenic succession. The share of fungi (mainly, of basidiomycetes) exceeded 90%. In the mineral root-inhabited soil horizons, the biomass of microorganisms was not greater than 1.0 mg/g. The soil under the lichen pine forest had the smallest biomass of microorganisms as compared to the soil under the pine forests that were not exposed to fire for a long time. At all the stages of the pyrogenic succession, the most favorable conditions for the functioning of microorganisms were in the root-inhabited horizons of the soils in near-stem sites due to the accumulation of nutrients there. In the soils of these zones, the basidiomycete biomass was greater than that in the soils of the gaps. In the mineral soil horizons, buckleless micromycetes demonstrated the same trend. No distinct parcella differences, with respect to the soil nutrient regime, were found only for the prokaryotes. The fungi in the Al-Fe-humus podzols may be used as indicators for the pyrogenic succession stages of forest ecosystems. At the early stages, micromycetes without buckles prevailed, and, in the course of succession, the share of basidiomycetes clearly increased. The density and structure of mycorrhiza were tightly related to the nutrient regime of the soils. The increase in the concentration of available biogenic elements in the root-inhabited soil horizons did not cause the necessity of developing complex mycorrhiza forms.  相似文献   

20.
Soil biodiversity includes organisms which spend a part or all of their life cycle on or in the soil. Among soil-dwelling animals, macro-fauna as an important group of animals have important effects on the dynamics of soil organic matter and litter decomposition process. The humus forms interact with the climatic conditions, flora, as well as soil fauna, and microbial activity. In new humus form classifications, soil organisms play an important role in separation of humus horizons from one another. The subject of this study was to determine the diversity of macro fauna for different humus forms. We determined humus forms using morphological classification, and then 69 random samples were taken from plots of 100 cm2 in area, and soil macro-fauna species were collected by hand sorting method. Two classes of humus forms, including Mull (with three humus orders, namely Dysmull, Oligomull, and Mesomull,) and Amphi (with four humus orders, namely Leptoamphi, Eumacroamphi, Eumesoamphi, and Pachyamphi) were identified. A number of 13 macro-fauna orders were identified using identification key. Among the humus orders, Shannon diversity, Simpson evenness and Margalef richness indices were the highest in Pachyamphi order. Arthropod diversity in Pachyamphi humus order was higher than those of Mull. These results showed that diversity of soil macrofauna increase by increasing the thickness of the organic horizons (OL, OF, OH), especially OH horizon.  相似文献   

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