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Chinese Science Bulletin 1994年第15期39卷 1290-1294页

作者：李取生 Changchun Institute of Geography Academia Sinica Changchun 130021 PRC

In Northeast China, peatlands and paleosols have developed very well in the eastern swamps and western sandy lands, respectively. They become an important object of studying the paleoenvironment in this region. Since both of them were formed under humid climate conditions, it is significant to compare their formation and ages for the unification of climatic change divisions and the reconstruction of the

关键词： Northeast China peatlands and paleosols of sandy land comparison study change of aridity.

paleosols AND THEIR ENVIRONMENTAL SIGNIFICANCE DURING HOLOCENE IN DAQINGSHAN MOUNTAIN REGION OF INNER MONGOLIA,NORTH CHINA

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Journal of Geographical Sciences 1992年第1期 72-83页

作者： Wu Wanli Department of Geography Peking University

Studies on the paleosol and the environmental changes during the Holocene in the Daqingshan Mountain were carried out based on the analyses of strata section structure,morphological properties,C data,physico-chemical characteristics and soil *** paleosol developed in five periods and are usually separated by horizons rich in gravels（"stone line"layers）.Fairly strong humus accumulation and weak carbonate eluviation processes are characteristic of the paleosol forming periods;and the"stone line"layers,consist of very high gravel content（30-60 percent）and low organic *** suggest that the climate condition in the paleosol forming period were warmer and wetter than that in the"stone line"forming ***,the sedimentary rhythm of the paleosol sections reveals the climatic fluctuation during the Holocene in this *** is believed that there probably experienced five climatic changes with coldarid and warm-humid climate alternating during the Holocene.

关键词： paleosols 14C age climatic change Inner Mongolia

paleosols and climates in the quaternary of south America

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Chinese Science Bulletin 1999年第S1期44卷 8-14页

作者： MartinH.Iriondo CONICET-Argentina Casilla de Correo 487 (3100)

Numerous paleosols have been described in the Quaternary as well as a fewpaleosols in pre-Quaternary rocks of South America. A broad ordering of the more importantoccurrences of paleosols show four main regions for pedogenesis: A) The lowlands adjacent to theSouth Atlantic (the Pampa and surrounding areas) with typical loess-paleosol and similarsequences. B) The Andes, characterized by paleosols intercalated with moraines, as high as 4000m.a.s.l., which are frequently developed in pyroclastic materials. C) The Caribbean region, wheresoil-forming processes underwent the following succession: Oxisols in the Lower Quaternary →Ultisols → Alfisols → Vertisols → Entisols in the Holocene. D) The Amazonian region locatedalmost permanently under udic moisture regimes of different types. The soils are typically Oxisolsand Ultisols.

关键词： paleosols climate Quaternary south America

Clay minerals in paleosols of cretaceous age in Istria,Croatia

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Chinese Science Bulletin 1999年第S1期44卷 145-151页

作者： F.OTTNER G.DURN B.SCHWAIGHOFERAND J.TIsLJAR University of Agricultural Sciences Vienna Department of Applied GeologyPeter Jordan Strasse 70 A1190.ViennaAustria University of Zagreb Faculty of mininggeology and petroleum engineeringPierottijeva 6HR-10000 ZagrebCroatia

Greenish clays often occur as thin layers in Early Cretaceous shallow-water carbonatesediments of Istria where they mark the top of fining upwards sequences. When they showevidence of subaerial exposure and pedogenesis they are considered paleosols. The claymineralogical composition is as follow: (1) randomly oriented I/S mixed layer, (2) regularlyoriented I/S mixed layer, (3) illitic material, (4) kaolinite and (5) chlorite. The insoluble limestoneresidue situated immediately below the greenish clays is dominated by smectite, and also containskaolinite and illitic material. The very high smectite content in the insoluble residue is probablythe result of additions of volcanic dust during carbonate sedimentation. That clay mineralcomposition in the pelitic material clearly indicates the influence of both pedogenic and diageneticprocesses. It may also indicate additional volcanic dust contribution before and during thesubaerial exposure.

关键词： Istria paleosols clay minerals illitization fining upwards sequences subaerial exposure

Middle Jurassic climate oscillations from paleosol records of the Sichuan Basin,SW China

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Journal of Palaeogeography 2022年第1期11卷 97-122页

作者： Jun Li Cheng-Min Huang Guo-Lin Yang Yuan-Yuan Pan Xing-Yue Wen College of Urban Environment Lanzhou City UniversityLanzhou 730070Gansu ProvinceChina Department of Environmental Science and Engineering Sichuan UniversityChengdu 610065Sichuan ProvinceChina BaiLie School of Petroleum Engineering Lanzhou City UniversityLanzhou 730070Gansu ProvinceChina School of Environmental Science and Engineering China West Normal UniversityNanchong 637002Sichuan ProvinceChina

The Middle Jurassic is characterized by major plate tectonic changes,variable atmospheric CO_(2)concentrations(pCO_(2)),and climate oscillations in both marine and terrestrial ***,the limited evidence from the terrestrial sedimentary records hampers a comprehensive understanding of global climate state in this ***-exposed strata of the Shaximiao Formation in the Sichuan Basin,Southwest China,preserve successions of paleosols that offer the possibility of evaluating the terrestrial paleoclimatic changes during the Middle Jurassic(Bajocian to Callovian).A total of 151 paleosol profiles belonging to four paleosol types(Entisol-like,Inceptisol-like,Aridisol-like and argillic Inceptisol-like paleosols)were identified and *** quantitative paleoclimate reconstructions based on the bulk geochemistry of paleosol horizons and depths of carbonate nodules indicate a generally semiarid-subhumid climate alternating with arid-humid and cool/warm-temperate climates during this time *** dynamic climate terminated in a dry,subhumid,humid/perhumid and superhumid moisture regime characterized by steppe/wet or rain forest floral *** suggest that these climatic fluctuations may have been related to global geodynamic(e.g.,the fragmentation of Pangea,“megamonsoonal”circulation,and bolide impacts)and regional tectonic uplift(e.g.,the uplift of the Longmenshan Mountains in the South China Block)during the Middle *** pCO_(2)estimates suggest relatively low pCO_(2)levels within the range of~100 ppm-~890 ppm during the Bajocian to *** results coincide with the threshold for the initiation of glaciation and may help to explain the occurrence of cool intervals in the generally warm *** pCO_(2)fluctuations,which coincide with paleotemperature variations in the low paleolatitudes of the Northern Hemisphere,are possibly attributable to global geological events(e.g.,wildfire events,eustatic sea-level oscillations,and th

关键词： paleosols Paleoprecipitation Paleotemperature Paleoatmospheric CO_(2) Shaximiao Formation Bajocian-Callovian

Authigenic titanite in weathered basalts: Implications for paleoatmospheric reconstructions

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Geoscience Frontiers 2020年第6期11卷 2183-2196页

作者： Alexey A.Novoselov Dailto Silva Carlos Roberto de Souza Filho Institute of Applied Economic Geology Universidad de ConcepcionConcepcionChile Institute of Geosciences University of CampinasCampinasSPBrazil

The stability of titanite is sensitive to temperature and partial pressure of *** finding of authigenic titanite grains in weathering regolith formed on Parana basalts,Brazil,under tropical climatic conditions,reveals the thermodynamically-driven conversion from calcite to titanite at elevated ambient *** unusual nowadays,this phase transition provides important implications for the understanding of silicate weathering in earlier geological *** types of secondary titanites were identified in the weathering profile of the study *** tiny grains of 10 μm are forming in the microscopic voids in the ***,large fractures filled with Fe-rich clay minerals contain bigger specimens of up to 170μ*** titanites of second type often coexist with chalcedony and *** carbonate minerals were found in the weathering *** sphene can be discriminated from other titanite types by its strong positive Eu anomaly,increased Al2 O3 content and low content of trace *** specific chemical composition and reactive transport modeling link this secondary mineral with dissolution of *** titanite precipitation is controlled by slow diffusion in poorly-aerated,highly-alkaline pore *** subaerial weathering of basaltic rocks provides a significant reservoir for atmospheric ***,the deposition of carbonate minerals is thermodynamically avoided at the stability field of *** demonstrate a complex feedback between CO2 and soil *** rise in pCO2 triggers the precipitation of calcite in the weathering regolith,but the greenhouse effect increasing the temperature can cease carbonate *** titanites were found in several paleosols and at least a part of them can be of weathering origin.

关键词： Titanite Sphene Calcite paleosols Weathering Paleoclimates

Bacterial Communities in a Buried Ancient Paddy Soil from the Neolithic Age

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Pedosphere 2010年第3期20卷 389-398页

作者： SHEN Wei-Shou YIN Rui LIN Xian-Gui CAO Zhi-Hong State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of SciencesNanjing 210008 (China) College of Chemistry and Environmental Science Nanjing Normal University Nanjing 210097 (China) Joint Open Laboratory of Soil and Environment Institute of Soil Science Chinese Academy of Sciences and Hong KongBaptist University Nanjing 210008 (China)

An ancient irrigated paddy soil from the Neolithic age was excavated at Chuodunshan Site in the Yangtze River Delta, close to Suzhou, China. The soil organic matter (SOM) content in the prehistoric rice soil is comparable to the average SOM content of present rice soils in this region, but it is about 5 times higher than that in the parent materials. As possible biomarkers to indicate the presence of the prehistoric paddy soil, the bacterial communities were investigated using the techniques of aerobic and anaerobic oligotrophic bacteria enumeration, Biolog analysis, and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). The results showed that in the buried soil layers, the prehistoric paddy soil had the largest number of aerobic and anaerobic oligotrophic bacteria, up to 6.12 and 5.86 log cfu g-1 dry soil, respectively. The prehistoric paddy soil displayed better carbon utilization potential and higher functional diversity compared to the parent materials and a prehistoric loess layer. The Shannon index and richness based on DGGE profiles of bacterial 16S rRNA genes were higher in prehistoric paddy soil than those in the prehistoric loess soil. It might be concluded that the prehistoric irrigated rice cultivation accumulated the SOM in plowed soil layer, and thus increased soil bacterial populations, metabolic activity, functional diversity and genetic diversity. Bacterial communities might be considered as the sensitive indicators of the presence of the prehistoric paddy soil in China's Yangtze River Delta.

关键词： biomarker denaturing gradient gel electrophoresis oligotrophic bacteria paleosols prehistoric paddy soil

Progress of loess research in China

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Journal of Geographical Sciences 2004年第S1期14卷 59-63页

作者： ZHAO Jingbo1,2, HUANG Chunchang1(1. Department of Geography, Shaanxi Normal University, Xi'an 710062, China 2. State Key Laboratory of Loess and Quaternary, Institute of Earth Environment, CAS, Xi'an 710075, China) Department of Geography Shaanxi Normal UniversityXi'an 710062China State KeyLaboratory of Loess and Quaternary Institute of Earth EnvironmentCASXi'an 710075China Department of Geography Shaanxi Normal UniversityXi'an 710062China

Progress in Chinese loess research made in recent 15 years was introduced in this paper, including mainly distribution and paleoenvironment significance of Chinese loess, new development of loess formation age, red-brown paleosol types and environmental change, loess-paleosol sequence and climate cycles, monsoon strength change during last interglacial and last glacial periods in the Loess Plateau, climate events, and source areas of loess and material.

关键词： Chinese loess paleosols loess age monsoon strength climate events material source

Influence of Elevation on Carbonate Contents in Stratified Soils, Northern Great Basin and Adjacent Mountains, U.S.A

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Open Journal of Soil Science 2011年第2期1卷 61-69页

作者： Arno Kleber 不详

Many soils in the western U.S.A. contain one or several carbonate-enriched zones (CEZ). Their carbonate admixture is often attributed to steady eolian influx, with intermittent leaching episodes of variable intensity leading to pedogenic enrichment at various depths. This hypothesis would require carbonate contents to decrease and depths to those horizons to increase with elevation. Here I compute correlations for the upper three CEZ of the surface soil and of up to two buried soils between elevation, carbonate content, depth to horizon, and particle-size distribution to test for elevation- dependent trends. Actually, carbonate-content decreases with elevation indicate such trends exist and can be determined with this approach. However, some significant relationship of elevation and depth to CEZ is not supported by the data. Furthermore, influence of local carbonate on CEZ in the surface soils calls for lateral translocation. Gravelly, now-buried sediments collected eolian carbonate better than finer ones, which finding implies these sediments were at the surface once and fossilized later. Altogether, the data indicate cyclical evolution: Several cycles of the formation of colluvial slope deposits with admixed carbonate-bearing loess particles were each followed by pedogenic translocation of the carbonate just to the depth of the next parent-material disconformity. Thus, disconformities are major triggers of soil-carbonate accumulation.

关键词： Soils and Elevation paleosols Soil Carbonate Pedogenesis Parent Materials

High resolution particle siz e analysis as a tool for interpreting incipient soils in loess

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Chinese Science Bulletin 1999年第S1期44卷 70-74页

作者： Joseph A. MASON PeterM.JACOBS IConservation and Survey Division and Department of Geosciences University of Nebraska-Lincoln 113 Nebraska Hall Lincoln Nebraska 68588-0517 U.S.A. Department of Geography University of Wisconsin-Whitewater. 800 West Main Street. Whitewater Wisconsin 53190 U. S. A.

Thick loess deposits in the central U.S.A. often contain incipient soil zones that haveslightly darker color, more clay, and in most cases, stronger soil structure than surroundingunweathered loess. These incipient soil zones can be interpreted as the direct result of warmer orwetter climatic episodes, or as the sedimentary result of changes in local loess deposition ***-resolution particle size analyses by laser diffraction support a sedimentary explanation forincipient soil zones in Illinois and Nebraska, U.S.A. The soil zones contain more fine silt and claythan loess above and below. This could have resulted from a temporary reduction in the localloess deposition rate, leading to a greater relative contribution of far-traveled dust that containedmore fine silt and clay.

关键词： loess paleosols particle size analysis laser diffraction