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1.
黄淮海平原晚第四纪古土壤 总被引：4，自引：0，他引：4
本文运用孢子花粉,古生物化石和放射性碳断代等手段,从土壤剖面层段的特征,土壤年龄和环境变化方面证明,分布于黄淮海平原的变性土不是现代土壤,而是古土壤,该古土壤自晚新世晚期以来经历了三次沉积－成土作用旋回,其土壤发育程度较弱,且是由钙质结核土层,暗色土层,表土层和（或）淤土层组成的一个叠置型古土壤。 相似文献
2.
A sequence of five paleosol units (with seven individual paleosol profiles) buried in the Late Pleistocene (20–40 ka) deposits
was studied at the Kostenki 14 (K14) key section in Voronezh oblast with the use of a set of morphological, physicochemical,
and instrumental methods. The upper-lying paleosols differed from the lower-lying paleosols in the less pronounced gley features,
stronger aggregation of the soil material, more significant accumulation of carbonates, and higher percentage of calcium humates
and fulvates. These features attested to the higher aridity of the paleoclimate and the development of the upper-lying paleosols
under grassy vegetation. Within the studied paleosol sequence, the most developed profiles were typical of the soils that
formed 27–32 ka ago during the Bryansk interstadial. The good aggregation, the presence of features left by the soil fauna
activity, the high magnetic susceptibility, and the morphology of the secondary carbonates in the studied paleosols suggest
that they were formed under meadow-steppe vegetation in well-drained positions and resembled modern cryoarid soils. 相似文献
3.
中国西北地区 ,从中新世以来就有持续不断的风尘沉积。这种风尘沉积作用即使在气候较为湿热的古土壤发育时期也未中断。黄土上土壤发生的独特性在于成土过程与风尘沉积的同步性。这种独特的成土过程使得土壤剖面深厚而均匀 ,常呈复合性状。古土壤与下伏黄土 ,不再是土壤与母质的关系 ;古土壤的真正母质应是成土过程中不断添加的风尘物质。古土壤中并不存在埋藏A层 ,对古土壤进行A、B、C等发生学层次的划分值得商榷。由于富含碳酸钙风尘物质的不断添入 ,成土作用强度受到不断削弱 ,绝大多数古土壤的成土作用强度未达到棕壤的发育强度。 相似文献
4.
Paleosols of the S coastal plain of Israel were studied in a characteristic sequence situated in the Ruhama badlands area. At the upper part of the sequence, there is a Loessial Arid Brown Soil (Calciorthids), characteristic of the mildly arid climate of the area. The soil has two calcic horizons and four clayey layers alternating with four calcareous layers which are beneath them. Physical, chemical, and magnetic‐susceptibility data and micromorphological evidence indicate that each clayey layer together with the calcareous layer beneath it forms a single pedogenic unit. These units are similar to modern Grumusolic soils (Xeric Paleargids or Xererthic Calciargids) that occur in the semiarid belt of the S coastal plain and develop on eolian‐dust parent material. The calcareous layers are in fact calcic horizons formed by leaching of the carbonates from the clayey layers and accumulated in the form of in situ carbonate nodules. The leaching of the carbonates is not complete; they were never completely leached in the past. This feature together with a typical brown color is also characteristic of the modern soils developed in the semiarid water regime of the area. The four superimposed paleosols represent four cycles. It is suggested that they were formed in two phases. During a dry environment, a short phase of rapid eolian‐dust accumulation prevailed, followed by a stable phase of soil development in a somewhat wetter climate. Dating by optically stimulated luminescence and previous dating by 14C in the area suggest that the upper two paleosol cycles belong to the Last Glacial period whereas the other two cycles are of an earlier age. The magnetic‐susceptibility values decrease with age and react different from temperate areas. Below the four cycles, two totally leached paleosols developed on sandy parent material occur. Both paleosols have a reversed magnetic polarity and are hence older than 780 ky BP. The upper one is a Brown Mediterranean soil, and the lower one is a Red Mediterranean soil. Thin‐section evidence suggests that they formed on terrestrial sand dunes. 相似文献
5.
6.
Conceptual models are suitable for describing internal relationships of complex systems, including soil. We used conceptual models, the Jenny's and Johnson and Watson-Stegner's models to understand the formation and evolution of soil. We studied 20 pedons in granitic hilly lands, loessial piedmont, and piedmont plain in southern Mashhad, northeast Iran. These soils were characterized by high levels of gypsum, especially in the granitic saprolites, which suggested the importance of the wind in shaping the soil structure. Jenny's model is a developmental and equilibrium model, which only describes the state of the soil formation factors and considers that each bioclimatic zone has a specific climax soil. It focuses on the genesis of the surface soil and is not suitable for buried soils and paleosols. Johnson and Watson-Stegner's model describes soil as a product of progressive and regressive processes due to horizonation or haploidization. Progressive processes during the last interglacial cycle created a well-developed paleosol with an argillic horizon in all landforms, except the piedmont plain. Developmental soil up-building by aeolian addition led to gypsum enrichment of the granitic saprolite. Erosion decreased soil thickness and exposed the argillic horizon. The Last Glacial Maximum led to greater deposition of loess, covering the paleosol. Humidity was higher during the early Holocene than today, leading to the development of a Bk horizon. This horizon was preserved in the stable surfaces of granitic hilly land and in the loessial piedmont, but buried on the piedmont plain via the deposition of alluvial sediments. Jenny's model could be used for current soil formation factors, whereas Johnson and Watson-Stegner's model required morphological characteristics of pedons for interpretation. 相似文献
7.
S. A. Sycheva S. N. Sedov M. A. Bronnikova V. O. Targulian E. Solleiro-Rebolledo 《Eurasian Soil Science》2017,50(9):991-1009
The results of a hierarchical morphogenetic, physicochemical, and mineralogical study of the Ryshkovo full-profile texture-differentiated paleosol of the Mikulino Interglacial from the section at Aleksandrov quarry in Kursk oblast are discussed. The correlation analysis of the stratigraphy of this section with global geological records made it possible to determine the position of the Ryshkovo paleosol in the chronostratigraphic system of the Late Pleistocene and to attribute it to stage MIS 5e; the duration of pedogenesis for this paleosol was no more than 12–15 ka. The results of the study indicate that the Ryshkovo paleosol is close in its properties to the Holocene soddy-podzolic soils of the East European Plain. No direct evidences in favor of the former interpretation of this paleosol as a lessivated soil genetically close to Luvisols of nemoral broadleaved forest of Central Europe have been found. The difference between the paleosol of the Mikulino Interglacial and the modern soddy-podzolic soils is mainly related to the distribution of clay coatings. In the upper part of the illuvial horizon of Mikulino paleosol, clay coatings are few in number, and typical tongues of podzolized (albic) material are absent in the profile. At the same time, silty coatings (skeletans) are abundant even in the lower part of the illuvial horizon. In general, the Mikulino paleosol is characterized by a smaller diversity of clay pedofeatures. These differences might be related to less contrasting fluctuations of the environmental conditions in the second half of the Mikulino Interglacial, to the periodical renewal of the eluvial part of Mikulino paleosol by erosional and accumulative processes, and to the absence of anthropogenic impacts on the soil during the Mikulino Interglacial. The burying of the Ryshkovo paleosol took place due to the intense development of erosional processes induced by the contrasting climatic events at the end of the interglacial period accompanied by catastrophic forest fires and sharp cooling of the climate upon the transition to the Valdai glaciation. 相似文献
8.
T. S. Demkina T. E. Khomutova N. N. Kashirskaya E. V. Demkina I. V. Stretovich G. I. El-Registan V. A. Demkin 《Eurasian Soil Science》2008,41(13):1439-1447
Chestnut paleosols buried under steppe kurgans about 4800, 4000, and 2000 years ago and their background analogues were studied
in the dry steppe zone on the Volga-Don interfluve. Morphological, chemical, microbiological, biochemical, and radiocarbon
studies were performed. Paleoclimatic conditions in the region were reconstructed on the basis of paleosol data. The ages
of microbial fractions isolated from the buried and surface soils were determined using the method of 14C atomic mass-spectrometry. It reached 2100 years in the A1 horizon of the buried paleosol, which corresponded to the archaeological
age of the kurgan (1st century AD). The ages of microbial biomass isolated from the B2 horizons of the buried paleosol and
the background surface soil comprised 3680 ± 35 and 3300 ± 30 years, respectively. The obtained data confirmed our assumption
about preservation of microorganisms of the past epochs in the paleosols buried under archaeological monuments. It is ensured
by various mechanisms of adaptation of soil microbial communities to unfavorable environmental conditions (anabiosis, transformation
of bacteria into nanoforms, etc.). The possibility to stimulate germination of the ancient dormant microbial pool isolated
from the buried paleosols by 2–3 orders of magnitude with the use of β-indolyl-3-acetic acid as a signal substance was demonstrated. 相似文献
9.
T. E. Khomutova T. S. Demkina A. V. Borisov I. I. Shishlina 《Eurasian Soil Science》2017,50(2):229-238
The size and structure of microbial pool in light chestnut paleosols and paleosolonetz buried under kurgans of the Middle Bronze Age 4600–4500 years ago (the burial mound heights are 45–173 cm), as well as in recent analogues in the desert-steppe zone (Western Ergeni, Salo-Manych Ridge), have been studied. In paleosol profiles, the living microbial biomass estimated from the content of phospholipids varies from 35 to 258% of the present-day value; the active biomass (responsive to glucose addition) in paleosols is 1?3 orders of magnitude lower than in recent analogues. The content of soil phospholipids is recalculated to that of microbial carbon, and its share in the total soil organic carbon is determined: it is 4.5–7.0% in recent soils and up to three times higher in the remained organic carbon of paleosols. The stability of microbial communities in the B1 horizon of paleosols is 1.3–2.2 times higher than in the upper horizon; in recent soils, it has a tendency to a decrease. The share of microorganisms feeding on plant residues in the ecological–trophic structure of paleosol microbial communities is higher by 23–35% and their index of oligotrophy is 3–5 times lower than in recent analogues. The size of microbial pool and its structure indicate a significantly higher input of plant residues into soils 4600–4500 years ago than in the recent time, which is related to the increase in atmospheric humidity in the studied zone. However, the occurrence depths of salt accumulations in profiles of the studied soils contradict this supposition. A short-term trend of increase in climate humidity is supposed, as indicated by microbial parameters (the most sensitive soil characteristics) or changes in the annual variation of precipitation (its increase in the warm season) during the construction of the mounds under study. 相似文献
10.
A vertical sequence of seven buried paleosols composing the Klimovsk pedocomplex was studied in the basin of the Sukhona River
(Vologda oblast). These paleosols were formed according to the accumulative model of pedogenesis (pedosedimentation model).
They had monogenetic profiles with eluvial-gley, structural, and carbonate-illuvial types of differentiation. The set of elementary
pedogenic processes responsible for the development of these soils included gleyzation in the surface horizon and around the
roots, the inter- and intrahorizon translocation and segregation of iron, structuring, humification, weathering, lessivage,
the migration and segregation of carbonates, and the synthesis of palygorskite and analcime. The studied paleosol profiles
make it possible to reconstruct seven pedogenetic stages; each of them lasted for about n × 102–103 years. The paleosols were formed on a flat lacustrine-alluvial plain with drying lakes and temporary streams. The stages
of inundation and water stagnation on the surface alternated with the stages of drying of the territory. The climate was warm,
with well-pronounced wet and dry seasons. Against this general climatic background, arid climatic epochs marked by the development
of calcic paleosols alternated with humid climatic epochs marked by the development of noncalcareous paleosols. 相似文献
11.
12.
A chronosequence of five Visean (Aleksinian–Venevian interval, C1v, 326–336 Mya) paleosols on the territory of Moscow calcareous sedimentary basin (Brontsy quarry, Kaluga region) was studied in detail. Two lowermost paleosols are coastal peat-bearing paleosols developed under mangrove vegetation. Three upper paleosols develop pedocomplexes, in which the lower part is the marine limestone altered to different degrees by weathering/pedogenesis with the formation of eroded Rendzina-type soil. It is overlain by paleosols developed from terrigenous sediments of playa origin. They are characterized by elevated concentrations of Fe, Mg, Ti, Ga, and some other elements; the formation of secondary micritic carbonates, iron oxides, and smectites; and increased values of geochemical indexes (such as CIA-K). Smectite (low-charged beidellite) predominates in these paleosols. Iron oxides are represented by goethite and lepidocrocite attesting to the predominance of oxygenic environments. Pedocomplex at the Mikhaylovian/Venevian boundary is overlain by non-marine palustrine deposits known as “black rhizoidal limestone.” The paleoclimate reconstruction based on the chemical composition data attests to its polycyclic character. The Mikhaylovian time was most humid was (~1000 mm/yr). Later, starting from Venevian, gradual aridization of the climate began and annual precipitation decreased to 750 mm/yr and less. 相似文献
13.
Smuel Jakab 《CATENA》2007,71(3):406
A sequence of surface soil profiles and buried soils described on the 4th, 3rd, 2nd and 1st terraces of different rivers in Transylvania is presented as part of an attempt to perform a paleopedologic interpretation of the dominant soil types of this area. Excepting the first terrace, the described soils were formed from Pleistocene slopewash deposits of Würm, or possibly of Riss age, which overlay alluvial terrace deposits. On the basis of fossil animal remains, periglacial cryostructures, prehistoric artifacts (Coţofeni culture of the transition period from the Neolithic to the Bronze Age) and Scythian graves an approximate age of different soil horizons, as well as the polycyclic nature of soils was established. There is no essential difference between a Würmian buried soil horizon and the argic Bt horizon of the surface soils; moreover, in some cases, the buried paleosols become the Bt horizon itself of the surface soils, through the thinning of the overlying deposits. Even if the possibility of formation of the argic Bt horizons during the postglacial until the end of Neolithic, cannot be excluded, from the presented situations it seems that these horizons in the Transylvanian Basin are Würmian relics, formed in the periglacial interstadials. In most of the cases Bt horizon has nothing in common genetically with the topsoil. 相似文献
14.
The mineralogical composition of the clay fraction and microfabrics of the cryogenic soil-loess sequences of the Middle and Late Pleistocene ages have been studied near the northern boundary of loess sediments on the East European Plain. Poorly ordered mixed-layered mica-smectitic minerals with different portions of smectitic layers predominate in the clay fraction; di-and trioctahedral hydromicas occupy the second place. The clay fraction also contains chlorite, clay-size quartz grains, and feldspars. Individual smectite is present in some of the samples. Interstadial chernozem-like paleosols are specified by the higher content of clay, the maximum concentration of smectitic layers in the mixed-layered minerals, and the presence of individual smectite. The clay fraction in the profiles of interglacial paleosols is sharply differentiated: in the eluvial part, it is depleted of smectite and enriched in kaolinite, hydromica, and clay-size quartz. These features allow us to suppose that interglacial paleosols were subjected to podzolization processes. According to the mineralogical indices, Middle Pleistocene paleosols can be differentiated into those subjected to lessivage (the Kamenskii interglacial paleosol) and podzolization (the Inzhavin interglacial paleosol). 相似文献
15.
M.L. Leamy 《Geoderma》1975,13(1):53-60
Field and laboratory methods used for the identification of paleosols in New Zealand are discussed, and examples are given of their application to both buried and relict paleosols. Field methods include a pedomorphic index based on the quantitative assessment of four or more selected diagnostic properties for each horizon, which is useful under certain conditions to express the relative degree of development of several profiles.The significance of paleosol identification is only fully appreciated when the paleosol is defined stratigraphically and interpreted in terms of time and environment. The basis for defining soil-stratigraphic units in parts of New Zealand is outlined. 相似文献
16.
P. G. Panin 《Eurasian Soil Science》2007,40(2):126-139
Paleosol studies were conducted on the Moskva-Oka interfluve in the center of the East European Plain. Three paleosol complexes were distinguished in the sequence of soil-loess deposits: the Mezin complex of the Late Pleistocene age and the Kamensk and Inzhavin complexes of the Middle Pleistocene. Each of them consisted of the paleosols of two phases: the earlier interglacial phase and the later interstadial phase. In some cases, the paleosols of these two phases were separated by a thin layer of sediments with distinct features of cryoturbation. Paleosols of the interstadial phases are represented by the dark-colored humus-rich meadowchernozemic and chernozem-like prairie soils. During the interglacial periods in the Middle and Late Pleistocene, the soils with pronounced eluvial-illuvial differentiation of their profiles were developed under forest cenoses. Data on the morphology of paleosols; their physical, chemical, and physicochemical properties (particle-size distribution, pH, humus, carbonates, amorphous and crystallized iron oxides, etc.); and their micro-morphological features studied in thin sections prepared from undisturbed soil monoliths make it possible to judge the character of the pedogenesis during different epochs. 相似文献
17.
Buried soil chronosequences under a series of Early Alan kurgans (burial mounds) in the Vladikavkazkaya depression of the Northern Caucasus, Russia, were studied to derive a high-resolution paleoclimatic record from the variations of the selected paleosol properties. Haplic Chernozems occur under kurgans and on the actual land surface. Three kurgan cemeteries, Brut 1, Brut 2 and Beslan, dated from the end of the second to the beginning of the seventh centuries AD have been studied. The cemeteries are situated close to each other under similar lithological and geomorphological conditions but differed in the paleosols' preservation. The Brut 2 site has been recently altered due to annual ploughing and intensive irrigation for more than 30 years. The background soils and paleosols of the Brut 2 site have been compared with synchronous soils of non-irrigated Brut 1 and Beslan sites to detect pedogenic properties that are less changed by irrigation and thus comprise the “soil memory”. Stronger black color of humus horizon, increase of humus content and decrease of humus δ13C values; clear signs of biological activity, absence of morphological and analytical signs of solonetz properties; diffused carbonate white soft spots in the Bca horizon and decreasing carbonate content are thought to be related to the comparatively humid climatic conditions in the region. On the contrary, relatively low humus content, tongue-like lower boundary of humus horizon, increase of humus δ13C values, morphological signs of solonetz properties together with high content of exchangeable Na, relatively large and clearly shaped carbonate white soft spots in the paleosols of the Brut 2 site, as well as increase of density, thickness of the carbonate pseudomicellium and high carbonate content in the upper part of profiles in the paleosols of the non-irrigated Brut 1 site are assumed to be xeromorphic features, indicating comparatively drier climatic conditions. The paleosols of the earliest chronointerval of burial (the end of the second to the beginning of the third centuries AD) demonstrate clear xeromorphic properties which indicate a relatively dry climate with a mean annual precipitation 50–100 mm less than today. The estimated duration of the period with such climatic conditions is thought to be not less than 100 years. In addition, those paleosols have some weak signs of humid conditions indicating that between the end of the first and the middle of the second centuries AD the climate was getting more moist, mean annual precipitation became equal or slightly higher than today. The paleosols buried in the first half of the fifth century AD again demonstrate the gradual enhancement of xeromorphic properties reflecting the next stage of droughts. Thus, the period with favourable humid climate when the Early Alan culture flourished in the Northern Caucasus was relatively short (about 400 years). Studying the detailed chronosequence in the non-irrigated Brut 1 site the records of intercentennial time scale soil properties variability produced by comparatively “fast” pedogenic processes typical for the steppe zone i.e., humus formation and accumulation, bioturbation, carbonate accumulation and transformation and solonetzization, have been provided. 相似文献
18.
B. N. Zolotareva L. A. Fominykh A. L. Kholodov L. T. Shirshova 《Eurasian Soil Science》2009,42(5):496-506
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
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.
利用放射性碳对中国变性土的年代确定 总被引：1，自引：0，他引：1
LIU Liang-Wu 《土壤圈》1996,6(2):147-153
Vertisols,which are mainly developed on fluvial and lacustrine deposits and basalt,are extensively distributed in China.66 samples of them for radiocarbon dating were collected across 5 porvinces and 1 autonomous region,ranging from warm-temperate to subtropical and tropical zones in China.The soil organic matter was dated via surface horizon,black soil horizon and dark-colour horizon of the vertisols,whereas carbonate through calcareous concretions and dispersed carbonate in soil profile using radiocarbon method.The present article elucidates the dates of genetic horizons,and of surface and buried vertisols as well.14C dating indicates that the surface vertisols were formed during the end of the late Pleistocene.ca.15600 years ageo.Correlation between depth of sampling and measured 14C age shows that age characteristics of the vertisols of China are close to those of West Germany,Italy,TUrnisia,Australia and Argentina,However,two buried vertisols developed on fluvial and lacustrine deposits were formed during different geological periods,The buried soils in warm-temperate zone were formed in the mid Holocene,while those in subtropics were buried at 12930 years B.P., and formed in the end of the late Pleistocene. 相似文献