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1.
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
2.
The Late Pleistocene sediments and soils are exposed in the paleogully (or buried balka) in the Aleksandrov quarry (central
part of the European Plain and Middle Russian Upland) The previous Mikulino-Valdai climatic and erosional cycles are illustrated
using silica biomorphic analysis. The distributions of sponge spicules and phytoliths have shown dynamic and stable changes
during the formation of interglacial pedosediments (OIS 5e). Such changes in alluvial, deluvial and pedological processes
formed local landscapes of the European Russia. 相似文献
3.
The genesis, evolution, and paleoecology of soils of the Early Valdai interstadials were investigated in the Aleksandrov quarry (Kursk oblast), a key section of the Late Pleistocene deposits in the periglacial area of the East European Plain. The soils developed in the uppermost parts of the buried hollows (investigated in 2009) were compared with the soils developed in the lower parts of the same hollows (investigated in 1988). The data obtained suggest that the soils in the upper parts of the hollows were developed under wetter and, at the same time, more percolative water regime than the soils in the lower parts of the hollows. These soils were formed in a semihumid climate under the forest-steppe vegetation. Forest groves existed in the upper parts of the erosional network amidst herbaceous meadow steppes. In general, the soil cover pattern of the Early Valdai interstadials corresponded to the modern soil cover pattern within the analogous landscapes. 相似文献
4.
Large-scale climate fluctuations reflected in the alternation of glacial and interglacial epochs have resulted in structural
changes in the landscape shell. Differences in heat and moisture supply have accounted for specific features of soil-forming
processes, zonality structure, and the ratio of soil formation and sedimentation processes. The sequence of types of soil
formation epochs is most completely reflected in the structure of loess-soil cryogenic formations, where specific features
of soil formation and sedimentation during no less than seven natural climatic macrocycles (over the past 800 ka, the Brunhes
paleomagnetic epoch) have been revealed and analyzed. Within macrocycles, three main types of soil formation epochs have been
distinguished: interglacial, interstadial, and pleniglacial (interphasial). Interglacial soil formation evolved from subtropical
in the Eopleitocene and Early Pleistocene to subboreal and boreal in the Middle and Late Pleistocene. Interstadial dark-colored
soils developed during early interstadial warmings at the beginning of glacial epochs and formed complexes with interglacial
soils. Pleniglacial soil formation was characteristic of the coldest phase of the Valdai glaciation, when sedimentation and
physical weathering absolutely prevailed over soil formation, leading to the development of specific synlithogenic soils.
In the periods of climate softening, interstadial soils of cryo-gley genesis were formed. 相似文献
5.
The stratigraphic rank of warming, distinguished in marine deposits as ‘marine oxygen isotope stage 7’ (MOIS 7) and recorded in terrestrial deposits as a palaeosol, has been discussed for a long time. The purpose of this paper is to describe the climate and environment of the time, determined from palaeopedological and palynological investigations of loess‐palaeosol sequences in the peri‐ and metha‐Carpathian zones, and to correlate these sequences with the Pleistocene stratigraphic units. The changes in chemical composition of the deposits were used to reconstruct the processes of chemical weathering and translocation of mobile elements during pedogenesis in three sections (Orzechowce, Galych and Velykyi Glybochok). The variability of the mean annual temperature and precipitation was estimated from the changes of elemental ratios resulting from chemical weathering and vegetation composition. From micromorphological analysis, the stages of palaeosol development and their transformation in cold periods were reconstructed. Pollen analysis carried out for the Velykyi Glyboczok, Maksymivka and Stari Kodaky sites, was used to reconstruct the vegetation cover and the temperature changes of the coldest and warmest months were calculated. The results indicate that the penultimate interglacial period, correlated with MOIS 7, comprised two warming periods separated by a profound cooling period. Warm periods were cooler than the last interglacial and more recent conditions. Vegetation was characterized by the co‐occurrence in changing proportions of patches of mixed forests and steppe vegetation. In the cold period, permafrost developed in places and cryogenic structures were formed. Regional differentiation of biotope environments, resulting from the increase in the continental nature of the climate towards the east, occurred during the whole interglacial period. 相似文献
6.
C. Zucca D. Sechi S. Andreucci S. M. Shaddad M. Deroma S. Madrau F. Previtali V. Pascucci S. Kapur 《European Journal of Soil Science》2014,65(4):420-435
A multidisciplinary approach was followed to study the pedogenic and palaeoclimatic information preserved in a buried palaeosol belonging to a Late Quaternary succession located along the bay of Alghero (north‐western Sardinia). The bay is dominated by a 5‐km long sandy beach‐ridge system backing an N‐S oriented lagoon system (Calich). The succession studied is characterized by basal shallow marine deposits, followed by clayey lagoon sediments and colluvial strata and capped by a relatively thick aeolianite. The research was based on pedological and sedimentological analyses, supported by optically stimulated luminescence (OSL) dating and by an in‐depth micro‐morphological study. Three main climatic pulses were highlighted during the Eemian. A wet period, with intense carbonate leaching occurred at the very beginning of the Eemian interglacial followed by very dry climatic conditions. This dry phase was long and arid enough to allow the formation of a thick calcrete hardpan, a typical feature of semi‐arid environments. The hardpan is dated at about 120 ka (kilo annum) and this dry event is tentatively associated with the late Eemian arid pulse (LEAP). The last phase of the Eemian recorded the restoration of a wetter climate. Finally, the succession indicated that even in a cooler environment, the central Mediterranean most probably maintained temperate conditions at least until the end of the MIS 5c (about 95 ka; early Würm). 相似文献
7.
Numerous studies have been devoted to the physical-chemical weathering processes leading to the creation of unique soil formations having their own history that induce soil-biotic diversity. However, the extent to which unique geomorphic formations influence soil biotic seasonal variation is not clear. Our aim was to define seasonal variations of soil biota in soils of different-aged terraces of the Makhtesh Ramon anticline erosional cirque in southern Israel. The strong effect of Makhtesh Ramon (Ramon Crater) erosional fluvial terrace age initiated by climatic changes during the Late Pleistocene–Early Holocene period on seasonal variations in both soil properties and the abundance and composition of soil biota were demonstrated. However, age dependence was not constant and values for observed soil properties and microbial activity were negligible between younger and older terraces for certain seasons, while free-living nematodes along with bacteria-feeding group were strongly dependent on the geomorphic features of the ages throughout the study period. 相似文献
8.
A generalized chronosequence of changes in the morphometric parameters of chernozems in the past 5100 years is analyzed. It
is shown that the development of chernozems in the center of the East European Plain is characterized by both long-term (interglacial,
encompassing the entire Holocene) and short-term (within separate climatic periods of the Holocene) trends. The long-term
trend of the evolution of ordinary chernozems developed from the loess-like calcareous loam consists of a continuous increase
in the thickness of the soil humus profile and an oscillating increase in the depth of the carbonate accumulations. The Late-Holocene
short-term trends of the natural evolution of chernozems are characterized by the high spatial heterogeneity related to the
patterns of climatic fluctuations and to the lithological composition of parent materials. In that period, the thickness of
genetic horizons in the forest-steppe chernozems was increasing faster than that in the steppe chernozems. 相似文献
9.
The genesis and spatial differentiation of the silty sands and loams deposited during the Late Valdai glaciation have been studied in the central part of the Russian Plain within the Mologa-Sheksna Lowland and on terraced slopes of the Ovinishchensk Upland (Yaroslavl oblast). The stratigraphy of these sediments on different elements of the local topography and data on their particle-size distribution suggest that they belong to the same paragenetic group. Some differences in the particle-size distribution can be explained by the specificity of sedimentation in periglacial lakes found at different geomorphic levels (from 102 to 180 m a.s.l.) during the Ostashkov phase of the Valdai glaciation. For the first time, statistically significant differences in the properties of Holocene soils developed at different hypsometric levels have been revealed. The degree of textural differentiation of the soils developed from silty loams increases with an increase in the absolute height of the surface. The analysis of factual materials makes it possible to suggest that a system of impounded lakes existed in this area during the Ostashkov (maximum) phase of the Valdai cryochron; the water level in these lakes reached a maximum height of 180 m a.s.l. 相似文献
10.
S. A. Sycheva 《Eurasian Soil Science》2009,42(1):13-23
The lithostratigraphic, radiocarbon, macro- and micromorphological, particle-size, and other analyses have been applied to
reconstruct the Holocene evolution of soils and landscapes on the high- and mediumlevel floodplains of the Nepryadva River
in the Kulikovo field area. It is shown that the soils buried within the thickness of alluvial sediments on the high- and
medium-level floodplains were formed in different times and had their own evolution patterns; the polygenetic nature of these
soils is demonstrated. The development of floodplain landscapes in the Holocene was affected by the long-term climatic fluctuations.
The bed of the high floodplain was formed during the Late Valdai glacial stage. The beginning of the development of an intricate
sequence of buried soils and sediments of the floodplain dates back to the Boreal period. This pedosedimentary sequence in
the studied area can be referred to as the Kulikovo sequence. In the course of its formation, the pedogenic stages with a
predominant development of soils alternated with the lithogenic stages of active alluviation and deposition of colluvial deposits
from adjacent slopes on the floodplain. 相似文献
11.
为更好地理解矿区土壤退化机理,该文利用137Cs技术研究了焦作矿区具有15a沉陷历史的采煤沉陷坡土壤侵蚀特征及其对土壤养分的影响。沉陷坡137Cs含量从坡顶到下坡逐渐降低,及至坡脚急剧增大且表现出最高的值。基于137Cs本底(1 645 Bq/m2),沉陷坡坡顶至下坡表现为土壤侵蚀,而坡脚为土壤沉积。沉陷坡土壤侵蚀高达3.75 kg/(m2·a),属于中度侵蚀。沉陷坡土壤黏粒含量沿下坡方向增加,表明水蚀的分选性搬运。与对照区相比,沉陷坡侵蚀区土壤总有机碳(total organic carbon,TOC)、水溶性有机碳(water-soluble organic carbon,WSOC)、全氮、碱解氮、全磷、有效磷含量均出现了显著降低(P0.05);沉积区除WSOC显著降低(P0.05)外,其他养分含量变化不明显(P0.05)。在沉陷坡的侵蚀区,TOC与WSOC含量沿下坡方向逐渐减小,表现出与137Cs一致的分布格局;其他养分含量的坡面变化与137Cs分布不一致。相较于对照区,WSOC/TOC与碳氮比、碳磷比在沉陷坡侵蚀强烈的坡位分别出现了显著增大与降低(P0.05)。研究结果表明:1)焦作矿区自采煤沉陷坡形成以来发生了较严重的水蚀;2)侵蚀引起的土壤再分配影响沉陷坡土壤碳、氮、磷动态,其中,土壤再分配对土壤碳动态的影响最强;3)在土壤侵蚀作用下,采煤沉陷坡侵蚀强烈的坡位土壤有效态碳、氮、磷养分潜在的侵蚀风险大。采煤沉陷坡土壤侵蚀及其对土壤养分的不利影响应引起矿粮复合区土地整治的关注。 相似文献
12.
基于三维激光扫描的崩岗侵蚀的时空分析 总被引：3，自引：6，他引：3
崩岗侵蚀过程及其侵蚀量的精准量化分析,是研究崩岗发育机理及其发展演化的基础,也是测算崩岗流域产沙输沙的前提,对崩岗预防和治理以及水土保持和生态建设具有理论和现实意义。本研究应用三维激光扫描技术,大致以半年为周期,在6次定位监测基础上,以广东五华县莲塘岗崩岗为例,对崩岗侵蚀过程进行了定量分析。研究表明,莲塘岗崩岗年平均侵蚀量为833 m3,其中雨季平均侵蚀量为499 m3,干季平均侵蚀量为291 m3,侵蚀模数高达222 408 t/(km2·a)。24 h降雨量大于等于50 mm的暴雨、特别是大于等于100 mm的大暴雨对崩岗侵蚀影响很大,暴雨总量与崩岗侵蚀量具有正相关关系。崩壁之下的崩积锥部位侵蚀量最大,占总侵蚀量的55.6%。40°~60°坡面的侵蚀量最大,占总侵蚀量的49%。最大侵蚀强度(单位面积侵蚀量)位于50°~60°和70°~80°的两个坡度区间。最为剧烈的侵蚀区为主沟与支沟两侧及沟头部位,侵蚀深度均大于1 m,最大深度可达2.5 m。前3个监测周期,沟道以快速下切、侧蚀和溯源侵蚀为主,兼有小规模崩塌;后2个监测周期,以重力崩塌为主,沟道侵蚀减弱。崩岗地形变化导致其水力与重力作用交替进行,使崩岗侵蚀呈现出波动式变化。 相似文献
13.
Urban pedosediments (cultural layers) dating back to the 10th–11th centuries AD and soddypodzolic soils buried under them
were studied in two archaeological excavations in Velikii Novgorod. Stages of their development were described. It was found
that the buried soddy-podzolic soils at the latest stages of their development were cultivated or were formed under meadow
vegetation. Weakly developed garden soils were described in the thickness of urban pedosediments. The lowermost organic cultural
layers in Velikii Novgorod were waterlogged and represented peatlike mass with well-preserved wood remains. The oxidation
of organic matter, gleyzation, and vivianite formation were described in them. The upper mineral layers were enriched in brick
debris and building lime. The processes of organic matter mineralization, alkalization, calcification, zoogenic turbation,
and biogenic structuring were clearly manifested in this part. Soil solutions infiltrated from the cultural layers caused
some alkalization of the buried soddy-podzolic soil. Diagenetic carbonates and vivianite appeared in some loci within the
eluvial and the upper part of the illuvial horizon of this soil. The entire cultural layer was subjected to contamination
with heavy metals. 相似文献
14.
O. S. Khokhlova N. L. Morgunova A. A. Khokhlov A. A. Gol’eva 《Eurasian Soil Science》2018,51(5):506-517
A multilayered archaeological site Turganik Settlement in the valley of the Tok River in the Cis- Ural steppe (Orenburg oblast) was examined with the use of paleopedological and microbiomorph methods. Ancient people inhabited this area in the Latest Neolithic (Eneolithic) (5th millennium BC) and Early Bronze (4th millennium BC) ages. It was found that cultural layers dating back to the Atlantic period of the Holocene had been formed under conditions of a predominance of grassy–forb vegetation with a small portion of tree species and dry climate; the ancient settlement was not affected by floods and was suitable for permanent living. It is probable that soils of the chestnut type with salinization and solonetzic features were developed in that time. The final stages of the accumulation of cultural layers were marked by strong shortterm floods, whose sediments partly masked the features of the previous long arid epoch. The highest degree of aridity was at the end of the Atlantic period. In the Subboreal and Subatlantic periods, soils of the meadowchernozemic type were formed; the spore–pollen spectra of these periods are characterized by a higher portion of tree species and by the presence of phytoliths of meadow grasses. The climatic conditions were generally colder and more humid, though some short-term aridization stages could take place. Some of these stages are recorded in the thickness of the studied sediments. 相似文献
15.
Three representative soil profiles developed during the Late Quaternary in Northern Cilento (South Italy) were studied by optical microscopy and SEM-EDS observation of thin sections to examine soil features as evidence for past climatic fluctuations.Two of the profiles are polygenetic and the third monogenetic. All these have a clear interglacial imprint, whereas the polygenetic profiles also contain other features, which can be related to periglacial conditions during the stadial glacial periods although in midlatitude coastal areas. All the paleosols show a strong marine influence during development, which probably resulted from windblown processes or submergence during past interglacial phases. 相似文献
16.
Patrick L. Abbott 《CATENA》1981,8(2):223-237
Ancient weathering profiles provide mute evidence of the major climatic regimes that operated in the southern California area during the Cenozoic Era. A tropical climate during part of the Paleocene and Early Eocene caused severe weathering of Jurassic andesitic rocks, Cretaceous granitic rocks and Late Cretaceous and Early Eocene terrigenous rocks. Erosional remnants of this paleosol exist as buried soils up to 30 meters thick and as exhumed soils on some modern hills. The main weathering horizon is overwhelmingly composed of kaolinite with residual quartz grains and minor amounts of iron oxides. This tropical climate was in effect at 35° to 40° north latitude.Late Eocene sedimentary rocks were deposited under a semi-arid climate with 50 to 60 cm of annual rainfall that was concentrated during one season. This interpretation is based on: 1) the dominance of conglomerate and immature sandstone in the Upper Eocene section compared to the relative scarcity of claystone, 2) the immaturity of the clay mineral suite which is dominated by smectite and vermiculite, 3) the presence of fractured clasts presumably split by growth and differential expansion of salts, 4) the multiple caliche beds that individually are up to one meter thick, and 5) the paleohydrology of the fluvial deposits which transported rhyolite gravels over 300 km distance from an eastern bedrock source about 4,000 m high in a river of 1.3 sinuosity with 100 year flood discharges up to 30,000 m3/sec.The extensive marine terraces in San Diego are mantled by relict soils that record composite weathering characteristics from glacial and interglacial climates from Late Pliocene to present. Maximal development of the paleosol includes an ironstone concretion layer (Bir horizon) above an illuvial clay layer (Bt horizon) which rests on an iron- and silicacemented hardpan (Cm horizon). 相似文献
17.
Patrick L. Abbott 《CATENA》1981,8(1):223-237
Ancient weathering profiles provide mute evidence of the major climatic regimes that operated in the southern California area during the Cenozoic Era. A tropical climate during part of the Paleocene and Early Eocene caused severe weathering of Jurassic andesitic rocks, Cretaceous granitic rocks and Late Cretaceous and Early Eocene terrigenous rocks. Erosional remnants of this paleosol exist as buried soils up to 30 meters thick and as exhumed soils on some modern hills. The main weathering horizon is overwhelmingly composed of kaolinite with residual quartz grains and minor amounts of iron oxides. This tropical climate was in effect at 35° to 40° north latitude.Late Eocene sedimentary rocks were deposited under a semi-arid climate with 50 to 60 cm of annual rainfall that was concentrated during one season. This interpretation is based on: 1) the dominance of conglomerate and immature sandstone in the Upper Eocene section compared to the relative scarcity of claystone, 2) the immaturity of the clay mineral suite which is dominated by smectite and vermiculite, 3) the presence of fractured clasts presumably split by growth and differential expansion of salts, 4) the multiple caliche beds that individually are up to one meter thick, and 5) the paleohydrology of the fluvial deposits which transported rhyolite gravels over 300 km distance from an eastern bedrock source about 4,000 m high in a river of 1.3 sinuosity with 100 year flood discharges up to 30,000 m3/sec.The extensive marine terraces in San Diego are mantled by relict soils that record composite weathering characteristics from glacial and interglacial climates from Late Pliocene to present. Maximal development of the paleosol includes an ironstone concretion layer (Bir horizon) above an illuvial clay layer (Bt horizon) which rests on an iron- and silicacemented hardpan (Cm horizon). 相似文献
18.
C.J. Chartres 《Geoderma》1980,23(2):125-146
The field characteristics, texture, mineralogy and micromorphology of the soils of four chronologically separate river terraces of the River Kennet are described. The soils on the three uppermost terraces have illuvial (palaeoargillic) horizons, which have been intensely disturbed by periglacial activity. These horizons are overlain by similarly disrupted eluvial horizons mixed with aeolian silts derived from outside the Kennet catchment. The illuvial horizons most probably result from interglacial pedogenesis under climatic conditions warmer and wetter than at present, whilst the aeolian material was probably added to the soils during the last glacial period (Devensian). The lowest and youngest terrace is characterised by an undisturbed (normal argillic) soil developed in loams derived predominantly from the aeolian silts. Consequently, it is postulated that the soils of the lowest terrace owe their characteristics to a phase of postglacial pedogenesis.The results illustrate that several phases of pedogenesis can be recognised, which provide important information on the Quaternary development of the area. This is especially significant where floral, faunal, or archaeological evidence of environmental changes is unavailable. 相似文献
19.
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
20.
采用模拟增降温法研究了温度变化对麦田地温、土壤水分变化和水分利用效率的影响。结果表明:模拟增温麦田、降温麦田在全生育期5 cm平均地温分别较常规麦田平均升高0.85℃和降低2.57℃,其中模拟增温麦田的增温效应以冬季>秋季>春季,模拟降温麦田的降温效应以春季>秋季>冬季;模拟增温麦田、降温麦田在全生育期5 cm土层的平均容积含水率分别较常规麦田降低3.76%、提高4.84%。对模拟增温麦田、降温麦田和常规麦田0-200 cm土层水分变化研究表明,模拟增温麦田和常规麦田(除成熟期外)各生育期的贮水量均低于模拟降温麦田;全生育期0-200 cm土层土壤耗水量模拟增温麦田大于模拟降温麦田和常规麦田,其中0-100 cm土层耗水量占0-200 cm土层耗水量的比例模拟增温麦田(55.72%)和常规麦田(55.14%)均低于模拟降温麦田(63.45%),而100-200 cm土层耗水量占0-200 cm土层耗水量的比例模拟增温麦田(44.28%)和常规麦田(44.86%)麦田均高于模拟降温麦田(36.55%);水分利用效率模拟增温麦田低于常规麦田和模拟降温麦田。研究结果可为气候变暖对小麦生产系统的影响提供理论依据和技术支撑。 相似文献