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Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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science china Earth sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2. JI Junfeg3. WANG Xiaoyong1,7, ZHAO Jingbo4, HUANG Baochun5 & LI Zhen6 1. SKLLQG, institute of Earth Environment, {2. academy of {3.s, Xi’an 710075, china 2. Department of Urban and Resources {3.s, nanjing University, nanjing 2.0093. china 3. Department of Earth {3.s, nanjing University, nanjing 2.0093. china 4. Department of Geography, Shaanxi Normal University, Xi’an 710062. china 5. institute of Geology and Geophysics, {2. academy of {3.s, Beijing 10002., china 6 Department of Geography, Qinghai Normal University, Xining 810008, china 7. Graduate School of the {2. academy of {3.s, Beijing 10003., china 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. Graduate School of the chinese academy of {2.s Beijing 100039 China 2. Department of Urban and Resources sciences Nanjing University Nanjing 210093 China 3. Department of Earth sciences Nanjing University Nanjing 210093 China 4. Department of Geography Shaanxi Normal University Xi’an 710062 China 5. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. Department of Geography Qinghai Normal University Xining 810008 China

The Red Earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 2. visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the {3.Loess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63.μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63.μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4 Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

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Spatial and Temporal Variability of N, P and K Balances for Agroecosystems in china

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Pedosphere 2005年第3期15卷 347-355页

作者： SHENRun-Ping SUNBo ZHAOQi-Guo instituteofsoil{2. ChineseAcademyofSciencesNanjing210008（China）／／DepartmentofSpatialInformationScienceNanjingUniversityofInformationScienceandTechnologyNanjing210044（China） instituteofsoil{2. ChineseAcademyofSciencesNanjing210008（China）

Nitrogen, phosphorus, and potassium balances for agroecosystems in china from 1993.to 2.01 were calculated at national and provincial levels using statistical data and related parameters, and their spatial and temporal variabilities were analyzed with GIS to estimate the potential impacts of nutrient N, P and K surpluses or deficits to {2., water and air. At the national scale, the N and P balances from 1993.to 2.01 showed a surplus, with the nitrogen surplus remaining relatively stable from 1997—2.01. Although during this period the P surplus pattern was similar to N, it had smaller values and kept increasing as the use of phosphate fertilizer increased year by year. However, K was deficient from 1993.to 2.01 even though from 1999 to 2.01 the K deficit decreased. The spatial analysis revealed higher N surpluses in the more developed southeastern provinces and lowest in the western and northern provinces where there was less chemical fertilizer input. The serious K deficit mainly occurred in Shanghai and Beijing municipalities, Jiangsu, Zhejiang and Hubei provinces, and Xinjiang autonomous regions. For the years 1992. 1996 and 2.01, N surpluses and K deficits had significant positive spatial correlations with per capita gross domestic product (GDP), per capita gross industrial output value, and per capita net income of rural households. This showed that the level of economic development played an important role on nutrient balances in the agroecosystems.

关键词： china economic factors NPK balance spatial and temporal variability

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Interaction of NPK Fertilizers During Their Transformation in soils: I. Dynamic Changes of soil pH

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Pedosphere 2003年第3期13卷 257-262页

作者： WANG HUOYAN, ZHOU JIANMIN, CHEN XIAOQIN, LI SHOUTIAN, DU CHANGWEN and DONG CAIXIAinstitute of soil {2., the {3. academy of {2.s, nanjing 2.0008 (china) institute of soil {2. the Chinese Academy of Sciences Nanjing 210008

Dynamic changes of soil pH as influenced by ammonium sulfate (AS),monocalciuin phosphate (MCP), potassium chloride (KCl) and their interaction in soils were evaluatedin incubation experiments. Applying these fertilizers significantly reduced soil pH values in allcases and followed sequences of AS > MCP > KCl, MCP > KCl > AS and KCl > AS > MCP for the paddy,calcareous and red soils, respectively. The AS-induced reduction of pH in the three soils followedthe sequence of red soil > paddy soil > calcareous soil, while in MCP and KCl systems the reductionof pH followed the sequences of calcareous soil > paddy soil > red soil and red soil > calcareoussoil > paddy soil, respectively. The interactions of the NPK fertilizers on pH were significant. MCPplus KCl or MCP plus AS reduced pH values more than the fertilizers applied solely in the paddysoil, but AS partly counteracted the effect of MCP on pH in the 1 d sample of the calcareous *** effect of MCP on pH was trivial when MCP was applied in combination with KCl or AS in the redsoil. When applied in combination with AS, KCl did not affect soil pH initially, but suppressed thereduction of pH at the later incubation stage, which was related to inhibition of nitrification byKCl in the soils.

关键词： nitrogen pH phosphorus potassium

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Nutrient Cycling and Balance in Red soil Agroecosystem and Their Management

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Pedosphere 2000年第2期10卷 107-116页

作者： HE YUANQIU and LI ZHIMING.(institute of soil {2., the {3. academy of {2.s, P.O. Box 82., nanjing 2.0008 china) 中科院南京土壤所江苏南京 210008

An experiment was conducted in a red soil derived from Quaternary red clay in the Ecological ExperimentStation of Red soil, the {2. {3. of sciences, located in Yingtan (2.° 15′ 3.″ N, 116° 55′ 3.″E), Jiangxi Province. The results show that the major ways of nutrient loss are leaching and nitrogenvolatilization. Rationalizing crop distribution, stimulating nutrient recycling, and improving internal nutrientflow are effective measures to decrease nutrient loss and to promote nutrient utilization efficiency. Theimportant ways of regulating nutrient cycling and balance in the agroecosystem of the red soil are to establishoptimal eco-agricultural models, practice balanced fertilization and combine the cropping system with thelivestock system.

关键词： balance nutrient cycling red soil agroecosystem regulation options

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^(15)N NMR Spectroscopic Study on Nitrogen Forms in Humic Substances of soils

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Pedosphere 2001年第1期11卷 1-9页

作者： WEN QIXIAO, ZHUO SUNENG and CHENG LILI (institute of soil {2., the {3. academy of {2.s, P.O. Box 82., nanjing 2.0008 (china)) 中科院南京土壤所江苏南京 210008

Nitrogen forms of humic substances from a subalpine meadow soil, a latentic red soil and a weathered coal and the effect of acid hydrolysis on N structures of soil humic substances were studied by using 15N cross-polarization magic angle spinning nuclear magnetic resonance (CPMAS NMR) spectroscopy. Of the detectable 15N-signal intensity in the spectra of soil humic substances 71%-79% may be attributed to amide groups, 10%-18% to aromatic/aliphatic amines and 6%~11% to indole- and pyrrole-like N. Whereas in the spectrum of the fulvic acid from weathered coal 46%, at least, of the total 15N-signal intensity might be assigned to pyrrole-like N, 14% to aromatic/aliphatic ammes, and the remaining intensities could not be assigned with certainty. Data on nonhydrolyzable residue of protein-sugar mixture and a 15N-labelled soil fulvic acid confirm the formation of nonhydrolyzable heterocyclic N during acid hydrolysis. Project (No. 3.790100) supported by the National Natural science Foundation of china.

关键词： forms of N humic substances mineral soils 15N CPMAS NMR weathered coal

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Grey Disorder in Field Flue-Cured Tobacco

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Pedosphere 1999年第4期9卷 369-374页

作者： ZHANG XIN ZHAO QIBO YU HUIMEI CAO ZHIHONG(1institute of soil {2., the {3. academy of {2.s, nanjing 2.0008 (china))(2.iangsu Provincial Tobacco Company, nanjing 2.0O2. (china)) 中科院南京土壤所江苏南京 210008 江苏省烟草公司江苏南京中科院南京土壤所江苏南京

A field study was carried out on the grey disorder in fine-cured tobacco (Nicotiana tabacum L.) *** results showed that low Eh and high available Fe content in the soils were responsible for the grey tobaccoand dead roots. Grey disorder leaves produced low quality lamina, which was low in N, nicotine, reducedsugar and K contents. In this study’ soil available Mn and leaf Mn contents were in a relatively low level andshould not be an important factor in the occurrence of grey disorder in fine-cured tobacco.

关键词： flue-cured tobacco grey disorder iron manganese toxicity

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Fractionation of Heavy Metals in soils as Affected by soil Types and Metal Load Quantity

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Pedosphere 2002年第4期12卷 309-319页

作者： ZHOU DONGMEI, CHEN HUAIMAN, HAO XIUZHEN and WANG YUJUNinstitute of soil {2., the {3. academy of {2.s, nanjing 2.0008 (china) institute of soil {2. the Chinese Academy of Sciences Nanjing 210008

Two series of soil subsamples, by spiking copper (Cu), lead (Pb), zinc (Zn) and cadmium (Cd) in an orthogonal design, were prepared using red soil and brown soil, respectively. The results indicated that heavy metal fractions in these soil subsamples depended not only on soil types, but also on metal loading quantity as well as on interactions among metals in soil. Lead and Cu in red soil appeared mostly in weakly specifically adsorbed (WSA), Fe and Mn oxides bound (OX), and residual (RES) fractions. Zinc existed in all fractions except organic bound one, and Cd was major in water soluble plus exchangeable (SE) one. Different from the results of red soil, Pb and Cu was present in brown soil in all fractions except organic one, but over 75% of Zn and 90% of Cd existed only in SE fraction. Meanwhile, SE fraction for any metal in red soil was lower than that in brown soil and WSA and OX fractions were higher. It is in agreement with low cation exchange capacity and large amounts of metal oxides included in red soil. Metal fractions in soil, especially for water soluble plus exchangeable one, were obviously influenced by other coexisting metals. The SE fraction of heavy metals increased with increasing loading amounts of metals in red soil but not obviously in brown soil, which suggest that metal availability be easily affected by their total amounts spiked in red soil. In addition, more metals in red soil were extracted with 0.2. mol L-1 NH4Cl (pH 5.40) than that with 1.0 mol L-1 Mg(NO3.2.(pH 7.0), but the reverse happened in brown soil, implicating significantly different mechanisms of metal desorption from red soil and brown soil.

关键词： fraction heavy metal interaction ionic impulsion soil

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Using soil surface gray level to determine surface soil water content

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science china Earth sciences 2010年第10期53卷 1527-1532页

作者： ZHU YuanJun1,2.WANG YunQiang1,2.& SHAO MingAn1,2.1 State Key Laboratory of soil Erosion and Dryland Farming on Loess Plateau,institute of soil and Water Conservation,Northwest A & F University,Yangling 712.00,{3. 2.institute of soil and Water Conservation,chinese academy of sciences & Ministry of Water Resources,Yangling 712.00,{3. 1. State Key Laboratory of soil Erosion and Dryland Farming on Loess Plateau Institute of Soil and Water Conservation Northwest A & F University Yangling 712100 China2. Institute of Soil and Water Conservation Chinese Academy of Sciences & Ministry of Water Resources Yangling 712100 China

How to determine surface soil water content(SWC) quickly and accurately is fundamental in studying eco-hydrological processes and their *** we use laboratory experiments to determine surface SWC using soil surface gray level(SGL) values.A negatively exponential relationship exists between SGL and SWC,i.e.,SGL increases with the decrease of *** can be estimated based on initial SGL value(surface gray level when SWC=0),SWC,and a surface roughness coefficient characterized by mean soil particle *** variation range of SGL was larger than that of SWC,indicating that changes in SWC were enhanced in SGL,and that SGL would thus be sensitive to changes in soil *** the 95% confidence level,SWC can be determined by using the relationship between SWC and SGL established by the *** determination of SWC has a high precision when SWC was between dry and saturated.

关键词： Loess Plateau soil water remote sensing surface roughness

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Impacts of Choerospondias axillaris Growth on Acidity of Udic Ferrosols in Subtropical china

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Pedosphere 2005年第1期15卷 95-102页

作者： LIQing-Man WANGXing-Xiang BIShu-Ping instituteofsoil{2. ChineseAcademyofSciencesNanjing210008China instituteofHydrobiology ChineseAcademyofSciencesWuhan430072China／／DepartmentofChemistryNanjingUniversityNanjing210093China DepartmentofChemistry NanjingUniversityNanjing210093China

Changes in acidity of Udic Ferrosols, caused by growth of Choerospondias axillaris (Roxb.) Burtt et Hill, in comparison to wild grass, were investigated for pH distribution in the soil profile, exchangeable acidity, and cation status in the soil leachate of a simulated leaching experiment. soils were sampled in profiles at 5 cm intervals to a depth of 100 cm. In the 15-60 cm layer the soils with 10-year old C. axillaris had significantly lower pH (P < 0.05), with the largest difference being 0.41; and in…

关键词： acidification Choerospondias axillaris Udic Ferrosols

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Theory and practice concerning classification for expansive soils using standard moisture absorption water content

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science china(Technological sciences) 2005年第1期48卷 31-40页

作者： YAO Hailin1, CHENG Ping2. YANG Yang1 & WU Wanping2.1. institute of Rock and soil Mechanics, {2. {3. of sciences, Wuhan 43.071, china 2. china Communications Second Highway Survey Design and Research institute, Wuhan 43.052. china 1. institute of Rock and soil Mechanics Chinese Academy of Sciences 430071 Wuhan China 2. china Communications Second Highway Survey Design and Research institute 430052 Wuhan China

A series of tests on physical, mechanical and chemical properties of expansive soils have shown that the standard moisture absorption water content (SMA) of expansive soils has a good linear relationship with montmorillonite content, cation exchange capacity, specific surface, and it also presents a linear relationship tendency to plastic index and free swell ratio. All this indicates that the above SMA is of clear significance in physics. The plastic index can better reflect the interaction extent between composition and dispersing character of grains, cation and clay minerals. Consequently, SMA can reflect the basic essential properties of expansive soils. On the basis of the classification results that have been published in literature and in consideration of the succession to the classification results for the free swell ratio, this paper puts forward three indexes, i.e. the SMA, plastic index and free swell ratio to classify expansive soils. The tests proposed for the classification indexes are easy to operate, simple in testing device and last a short time. Compared with the latest issued “Classification Standard Code for Rocks and soils of Railway Projects” (TB10077-2.01), the method proposed in this paper is more convenient and reasonable, and can be popularized, when environment conditions ripen, for the application in field of exploration and design of highway in the areas surrounded by expansive soils.

关键词： expansive soil, standard moisture absorption water content (SMA), plasticity index, free expansive ratio, identification and classification of expansive soils.

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