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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, chinese academy of {3.s, Xi’an 710075, china 2. Department of Urban and Resources {3.s, nanjing University, nanjing 210093. china 3. Department of Earth {3.s, 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 {3.s, Beijing 100029, china 6 Department of Geography, Qinghai Normal University, Xining 810008, china 7. Graduate school of the chinese 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 sciences 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 25 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.

Effect of Lanthanum on Major Microbial Populations in Red soil

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Pedosphere 2001年第1期11卷 73-76页

作者： CHU HAIYAN, WANG JUNHUA, XIE ZUBIN, ZHU JIANGUO, LI ZHENGAO and CAO ZHIHONG (institute of soil science, the {3. academy of sciences, nanjing 21.008 (china)) 中科院南京土壤所江苏南京 210008

Pure culture and pot culture experiments were carried out to study the effect of lanthanum (La) on bacteria, actinomyces and fungus, and some microbial physiological groups , nitrifier, azotobacter and phos- phobacteria, in a red soil taken form the Ecological Experimental station of Red soil, the chinese {3. of sciences, Jiangxi Province. LaCl3.was added into media at levels of 0, 25, 50, 100, 150, 200, 250 and 500 mg L-1 in the pure culture experiment, and into soil samples in porcelain pots before rice growing at levels of 0, 6, 3., 150, 3.0, 600 and 900 mg kg-1 dry soil in the pot culture experiment. The populations of the three soil microbes in the pure culture experiment decreased with the addition level of La, indicating that La was toxic to the soil microbes in pure culture, and the sensitivity of the 3.major microbial types to La was in a decreasing order of actinomyces > bacteria > fungus. In the pot experiment, La had slightly stimulative effect on soil bacteria and actinomyces when applied at low concentrations while had inhibitory effect on soil bacteria, actinomyces and fungus at high concentrations. When the concentration of La was low, soil azotobacter was stimulated slightly while soil nitrifier was stimulated strongly and the maximum increase was up to 50%. When the concentration of La was high, both soil azotobacter and nitrifier were inhibited, and the inhibition of La to the nitrifier increased with La concentration. La added at all the levels had stimulative effect on soil inorganic and organic phosphobatteria. Among the 4 physiological groups, soil nitrifier was most sensitive to La, so , it might be reasonable to assume that soil nitrifier was a sensitive indicator for evaluating the biological and environmental effects of rare earths.

关键词： lanthanum microbial populations physiological groups rare earths red soil

sustainable Nutrient Management in chinese Agriculture: Challenges and Perspective

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Pedosphere 2006年第2期16卷 253-263页

作者： GAO Chao sUN Bo ZHANG Tao-Lin Department of Geography Nanjing University Nanjing 210093 （China）. institute of soil science Chinese Academy of Sciences Nanjing 2100（78 （China）

china has to raise agricultural productivity in its limited and shrinking farmland to guarantee food security for its huge and ever-growing population. sustainable soil nutrient management is of paramount importance to the world's most populous country. Critical challenges the country is facing in sustaining soil fertility and in alleviating the hazardous impact of intensive fertilizer use are discussed in this paper. It is emphatically pointed out that national strategies as well as area-specific action plans with respect to scientific nutrient management are urgently needed to balance productivity and sustainability in the future. Relevant proposals for addressing those challenges are also presented.

关键词： china food security nutrient management soil fertility water quality

Modeling Nitrogen Mineralization in Paddy soils of shanghai Region

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Pedosphere 2003年第4期13卷 331-336页

作者： LI Hui-Lin, HAN Yong and CAI Zu-CongLaboratory of Material Cycling in Pedosphere, institute of soil science, the {3. academy of sciences, P. O. Box 821, nanjing 21.008 (china). E-mail: lihuilin@*** Laboratory of Material Cycling in Pedosphere Institute of Soil Science the Chinese Academy of SciencesP. O. Box 821 Nanjing 210008 China

six paddy soils of shanghai, china, were studied after 120 days of anaerobicincubation at 25 deg C and 3. deg C. Four models, the effective accumulated temperature model, theone-component first-order exponential model (the one-pool model), the two-component first-orderexponential model (the two-pool model), and the two-component first-order plus zero-orderexponential model including a constant term (the special model), were fitted to the data of observedmineral-N during incubation using non-linear regression procedures. The two-pool model and thespecial model gave the best fits amongst the four models, and parameters in the special model weremore reasonable than those in the other three. Results showed that the special model gave a betterprediction of nitrogen mineralization under flooded conditions than the other three models.

关键词： anaerobic incubation nitrogen mineralization paddy soil simulation model

surface N Balances in Agricultural Crop Production systems in china for the Period 1980-2015

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Pedosphere 2008年第3期18卷 304-315页

作者： sUN Bo sHEN Run-Ping A. F. BOUWMAN Institate of soil science Chinese Academy of Sciences Nanjing 210008 （China） nanjing University of Information science and Technology Nanjing 210044 （China） National institute for Public Health and the Environment P. O. Box 303 3720 AH Bilthoven （The Netherlands）

surface nitrogen （N） balances for china＇s crop production systems was estimated using statistical data collected from 1980 to 2004 at the national and provincial scale and from 1994 to 1999 at the county level. There was a surplus N balance throughout these periods, but the surplus was nearly stable in recent years. Projections using nonseasonal Box-Jenkins model or exponential models show that the N surplus for the total cultivated land in china was likely to increase from 142.8 kg ha^-1 in 2004 to 168.6 kg ha 1 in 2015. The N balance surplus in the more developed southeastern provinces was the largest, and was slightly less in the central region, which caused the nitrate pollution in the ground water. The N surplus was much less in the western and northern provinces because of lower synthetic fertilizer inputs. The region with high N risk includes Beijing Municipality and Jiangsu, Zhejiang, Fujian, Guangdong, Hubei, and shandong provinces for 2002-2004. The projections suggested that 15 provinces （or municipalities） in the middle and southeastern part of china except Jiangxi and shanxi provinces would become the high-risk region by 2015. The level of economic development, transportation, and labor force condition had an important effect on the N balance surplus at the county level, but the last two factors showed remarkable impact at the provincial level. To decrease the nonpoint pollution （Npp） risk from crop production, the authors suggested to reduce the target level for national grain self-sufficiency to 90%-95% and change the regional structure of grain production by moving some of the future grain production from the high Npp risk areas of eastern china to parts of the central and western provinces where the Npp risk was much less.

关键词： agriculture china driving force nonpoint pollution risk surface nitrogen balance

spatial distribution of surface rock fragment on hillslopes in a small catchment in wind-water erosion crisscross region of the Loess Plateau

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science china Earth sciences 2008年第6期51卷 862-870页

作者： ZHU YuanJun1,2 & sHAO MingAn1 1 institute of soil and Water Conservation, chinese {3. of sciences and Ministry of Water Resources, Northwest Agriculture and Forestry University, Yangling 712100, china 2 institute of Geographical sciences and Natural Resources Research, chinese {3. of sciences, Beijing 100101, china 1. institute of soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Northwest Agriculture and Forestry University Yangling 712100 China 2. institute of Geographical {1.s and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

The cover and size distributions of surface rock fragment in hillslopes were investigated by using digital photographing and treating technique in a small catchment in wind-water erosion crisscross region of the Loess Plateau. The results indicated that the maximal cover of rock fragment was pre-sented at mid-position in steep hillslope. Rock fragment presented a general decreasing-trend along the hillslope in gentle hillslope. Rock fragment cover was positively related to gradient, rock fragment size decreased generally along the hillslope, and the size reduced with the gradient. The mean size of rock fragment was at a range of 6―20 mm in the steep hillslope, rock fragment size > 50 mm was rarely presented. The covers of rock fragment at different positions were markedly related to the quantities of rock fragment stribution of rock fragment in the hillslopes.

关键词： wind-water erosion crisscross region of the Loess Plateau small catchment hillslope surface rock fragment cover and size

Evaluation of N2-Fixation Capacity of Leguminous shrub Plants

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Pedosphere 2000年第2期10卷 159-163页

作者： sHI sHULIAN DU LIJUAN, CAO YACHENG and sUN GUOQING(institute of soil science, the {3. academy of sciences, P.O. Box 821, nanjing 21.008 china) 中科院南京土壤所江苏南京 210008

N2-fixation percentages in the aerial parts of the first and second cuttings of five species of leguminousshrub plants, i.e., Lespedeza formosa (Vog.) Koehne from Jiangxi, Lespedeza pllosa (Thunb.) sieb et Zucc.,LesPedeza formosa (Vog.) Koehne from Zhejiang, Cajanus cajan (L.) Millsp. and Indigofera pseudotinctoriaMats., of three genera were investigated in terms of pot culture experiment using natural 15N abundancemethod with Bischofia javanica B1., Camptotheca acuminata Decne. and Gardenia jasminoides Ellis asreference plants. Results showed that the N2-fixation percentages were different for the three genera ofleguminous shrubs but almost the same for three species in the same genus. I. pseudotinctoma Mats. hadthe highest N2-fixation percentage in its aerial part, and then followed by Lespedeza and C. cajan. TheN2-fixation percentages in the aerial parts of the plants that had grown for three years tended to be lowerthan those of the onesyear-old plants except L. formosa (Vog.) Koehne from Zhejiang and L. formosa (Vog.)Koehne from Jiangxi.

关键词： leguminous shrub natural 15N abundance method N2-fixation percentage

Wien Effect Characterization of Interactions Between Ions and Charged sites on Clay surfaces of Variable-Charge soils

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Pedosphere 2009年第5期19卷 545-553页

作者： ZHU Hao-Wen WANG Yu-Jun ZHOU Jun JIANG Jun LI Cheng-Bao ZHOU Dong-Mei s. P. FRIEDMAN Key Laboratory of soil Environment and Pollution Remediation Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) state Key Laboratory of soil and sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) institute of soil Water and Environmental Sciences Agricultural Research Organization the Volcani Center Bet Dagan 50250 (Israel)

To investigate the interactions of oppositely charged sites on the surfaces of variable-charge soil particles with cations and anions, and to evaluate the mean Gibbs free binding and adsorption energies of various cations on particles of red soil and latosol, clay fractions smaller than 2 μm were separated from samples of the two variable-charge soils. Ferric oxides were removed from part of the clay fractions, which were then saturated with various chlorides （NaC1, KCl, CaCl2, CdCl2 or LaCl3.. Electrical conductivities （EC） of dilute suspensions of the original and of the iron oxides-free clay fractions in deionized water were measured with the sHP-2 short high-voltage pulse apparatus, which enables measurement of the Wien effect at field strengths （E） from 14 to 250 kV cm^-1. The Wien effect （EC-E） curves revealed EC increases of red soil suspensions between 14 and 200 kV cm^-1, of 8.3. 8.4, 12.1, 5.9, and 1.2 μs cm^-1 for NaCl, KCl, CaCl2, CdCl2, and LaCl3. respectively, reflecting the differing interactions with the various cations and chloride. The EC increments with the iron-free red soil suspensions were higher, being 29.7, 17.2, and 15.3.μs cm^-1 for NaCl, CaCl2, and CdCl2, respectively. In the natural latosol suspensions the EC increments were practically zero, whereas in the iron-free fractions there were significant EC increments of 10.3. 5.7, 5.0, and 1.6μs cm^-1 for NaCl, CaCl2, CdCl2, and LaCl3. respectively.

关键词： electrical conductivity field strength iron oxide overlapping ζ potential

Microbial Biomass Carbon and Total Organic Carbon of soils as Affected by Rubber Cultivation

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Pedosphere 2003年第4期13卷 353-357页

作者： ZHANG Hua and ZHANG Gan-Lininstitute of soil science, the {3. academy of sciences, P. O. Box 821, nanjing 21.008 institute of soil science the Chinese Academy of Sciences P. O. Box 821 Nanjing 210008 China

soil samples were collected from different rubber fields in twenty-five plotsselected randomly in the Experimental Farm of the chinese academy of Tropical Agriculture {3.slocated in Hainan, china, to analyse the ecological effect of rubber cultivation. The results showedthat in the tropical rubber farm, soil microbial biomass C (MBC) and total organic C (TOC) wererelatively low in the content but highly correlated with each other. After rubber tapping, soil MBCof mature rubber fields decreased significantly, by 55.5 percent. compared with immature rubberfields. soil TOC also decreased but the difference was not significant. Ratios of MBC to TOCdecreased significantly. The decreasing trend of MBC stopped at about ten years of rubbercultivation. After this period, soil MBC increased relatively while soil TOC still kept indecreasing. soil MBC changes could be measured to predict the tendency of soil organic matterchanges due to management practices in a tropical rubber farm several years before the changes insoil TOC become detectable.

关键词： microbial biomass carbon organic C rubber tropical soils