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Pedosphere 1996年第2期6卷 167-173页

作者： WU YOUXIAN(institute of soil science,Acodemia sinica,P.O.Box 821,{3. 21.008 china) institute of soil science Academia Sinica P. O. Box 821 Nanjing 210008 China

some electrochemical properties,such as PH,Eh,and voltammetric behavior,of the decomposition products of rice straw and the in eractions of these products with soils were *** PH,Eh,and amounts of organic reducing substances changed markedly during the 60-day anaerobic *** decreased sharply to pH 5 on the tenth day and then increased gradually to 7 on the 45th *** amouats of organic reducing substances increased almost synchronously with the fall of redox potential during the first 15 *** differential pulse voltammetric(dpv) behavior changed not only in the peak current but also in the peak *** fractions with apparent molecular weights lower than 200 dations appeared to be active in dpv *** electric charge of organic reducing substances was closely related to the decomposition *** 6th day of incubation was the crucial time before and after which the major part of the components was negatively charged and positively charged, *** group with a low apparent molecular weight and a negative charge was the main components responsible for the lower anodic peak *** were oxidized first during the interactions of the organic reducing substances with soils.

关键词： electrochemical properties organic reducing substances rice straw variable charge soils

Radiocarbon Dating of Vertisols in china

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Pedosphere 1996年第2期6卷 147-153页

作者： LIU LIANGWU(institute of soil science,Academia sinica,P.O.Box 821,{3. 21.008 china) institute of soil science Academia Sinica P. O. Box 821 Nanjing 210008 China

Vertisols,which are mainly developed on fiuvial and lacustrine deposits and basalt,are extensively distributed in china. 66 samples of them for radiocarbon dating were collected across 5 provinces and 1 autonomous region, ranging from warm-temperate to subtropical and tropical zones in *** 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 *** 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 Argeentia. However, two buried vertisols developed on fluvial and lacustrine deposits were formed during different geological *** buried {1.s in warm-temperate zone were formed in the mid Holocene, while those in subtropics were buried at 1293. years B.P.,and formed in the end of the late Pleistocene.

关键词： buried vertisois soil￣(14)C age surface vertisols

Effect of Arbuscular Mycorrhizal Inoculation on Plant Growth and Phthalic Ester Degradation in Two Contaminated soils

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Pedosphere 2005年第2期15卷 263-269页

作者： CHENRui-Rui YINRui LINXian-Gui CAOZhi-Hong instituteofsoilscience ChineseAcademyofSciencesNanjing210008（China）

A 60-day pot experiment was carried out using di-(2-ethylhexyl) phthalate (DEHP) as a typical organic pollutant phthalic ester and cowpea (Vigna sinensis) as the host plant to determine the effect of arbuscular mycorrhizal inoculation on plant growth and degradation of DEHP in two contaminated soils, a yellow-brown soil and a red soil. The air-dried soils were uniformly sprayed with different concentrations of DEHP, inoculated or left uninoculated with an arbuscular mycorrhizal (AM) fungus, and planted with…

关键词： arbuscular mycorrhizae phthalic ester degradation plant growth soil pollution

Dynamic calculation model and seismic response for frame supporting structure with prestressed anchors

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science china(Technological sciences) 2010年第7期53卷 1957-1966页

作者： DONG JianHua1’2, ZHU YanPeng1, ZHOU Yong1 & MA Wei2 1 College of Civil Engineering, Lanzhou University of Technology, Lanzhou 73.050, china 2 state Key Laboratory of Frozen soil Engineering, Cold and Arid Regions Environmental and Engineering Research institute, {3. academy of sciences, Lanzhou 73.000, china 1. College of Civil Engineering Lanzhou University of Technology Lanzhou 730050 China2. State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

A dynamic calculation model of frame supporting structures with prestressed anchors for the slope stability is proposed. The frame and soil are closely contacted in the role of prestressed anchors and they cannot be separated along the whole slope. The lateral displacement of frame and soil is nearly in phase. The movement characteristic satisfies the theory of elastic foundation beam. The frame is treated with elastic foundation beam in this model. The influence of prestressed anchors is simplified as linear spring and damped system related with velocity. Under the condition of horizontal earthquake excitation, the equation of vibration response is established by using the model of dynamic Winkler beam and the analytical solutions are obtained for simple harmonic vibration. This method is applied to a case record for illustration of its capability, in order to verify the method, 3. nonlinear FEM (ADINA) is used to analyze the seismic performance of this case, the comparative results show that the design and the analysis are safe and credible by using the proposed method. The calculation model provides a new way for earthquake analysis and seismic design of slope stability supported by frame structure with prestressed anchors.

关键词： frame supporting structure with prestressed anchor slope dynamic calculation model seismic performance seismic design

Difference in selenium Accumulation in shoots of Two Rice Cultivars

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Pedosphere 2006年第5期16卷 646-653页

作者： ZHANG Lian-He sHI Wei-Ming WANG Xiao-Chang state Key Laboratory of soil and sustainable Agriculture Institute of Soil Science Chinese Academy of SciencesNanjing 210008 （China） Agricultural College Henan University of Science and Technology Luoyang 471003 （China） Department of Tea science Zhejiang University Hangzhou 310029 （China）

Two japonica rice （Oryza sativa L.） cultivars, Xiushui 48 and s. Andrea, differing in their ability to accumulate se in the grain （as high as a three-fold difference）, were compared for selenium （se） accumulation in their shoots when their growth media was supplied with different forms of se. Results indicated that when treated with 0.25μmol L^-1 Na2seO3. Xiushui 48 accumulation of se in the shoots was significantly more rapid （P〈0.05） than s. Andrea, probably because of greater se uptake and transport in Xiushui 48. Xiushui 48 rice seedlings had a higher shoot-se accumulation rate and absorbed selenocysteine （se-Cys） more rapidly than s. Andrea seedlings. However, when treated with se as 0.25μmol L^-1.selenomethionine （se-Met）, the s. Andrea seedlings＇ accumulation rate was significantly greater （P〈0.05） than that of Xiushui 48. Possibly, the high se accumulation rate of Xiushui 48 seedling shoots compared to s. Andrea shoots was the result of a higher capacity of Xiushui 48 to transform selenite to organic se compounds and a higher selenite uptake rate.

关键词： rice cultivars se accumulation selenite transport uptake rate

Effect of Long-Term Rice straw Return on soil Glomalin, Carbon and Nitrogen

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Pedosphere 2007年第3期17卷 295-302页

作者： NIE Jun ZHOU Jian-Min WANG Huo-Yan CHEN Xiao-Qin DU Chang-Wen institute of soil science Chinese Academy of Sciences Nanjing 210008 （China） soil and Fertilizer institute of Hunan Changsha 410125 （China） Graduate University of chinese academy of sciences Beijing 100049 （China）

A long-term experiment was conducted to investigate how long-term fertilization and rice straw incorporation into soil affect soil glomalin, C and N. The combined application of chemical fertilizer and straw resulted in a significant increase in both soil easily extractable glomalin (EEG) and total glomalin (TG) concentrations, as compared with application of only chemical fertilizer or no fertilizer application. The EEG and TG concentrations of the NPKs (nitrogen, phosphorus, and potassium fertilizer application + rice straw return) plot were 4.68% and 5.67% higher than those of the CK (unfertilized control) plot, and 9.87% and 6.23. higher than those of the NPK (nitrogen, phosphorus, and potassium fertilizer applied annually) plot, respectively. Application of only chemical fertilizer did not cause a statistically significant change of soil glomalin compared with no fertilizer application. The changes of soil organic C (sOC) and total N (TN) contents demonstrated a similar trend to soil glomalin in these plots. The sOC and TN contents of NPKs plot were 15.01% and 9.18% higher than those of the CK plot, and 8.85% and 14.76% higher than those of the NPK plot, respectively. Rice straw return also enhanced the contents of microbial biomass C (MBC) and microbial biomass N (MBN) in the NPKs plot by 7.76% for MBC and 3..42% for MBN compared with the CK plot, and 12.66% for MBC and 15.07% for MBN compared with the NPK plots, respectively. Application of only chemical fertilizer, however, increased MBN concentration, but decreased MBC concentration in soil.

关键词： C glomalin long-term fertilizer experiment N rice straw return

3. thermo-hydro-mechanical-migratory coupling model and FEM analyses for dual-porosity medium

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science china(Technological sciences) 2010年第8期53卷 2172-2182页

作者： ZHANG YuJun 1&ZHANG WeiQing 2 1.state Key Laboratory of Geomechanics and Geotechnical Engineering,institute of Rock and soil Mechanics, {3. academy of sciences,Wuhan 43.071,china 2school of Civil Engineering,southwest Jiaotong University,Chengdu 61003.,china 1. state Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China2. School of Civil Engineering Southwest Jiaotong University Chengdu 610031 China

One kind of 3. coupled thermo-hydro-mechanical-migratory model for saturated-unsaturated dual-porosity medium was established,in which the stress field and the temperature field are single,but the seepage field and the concentration field are double,and the influences of sets,spaces,angles,continuity ratios,stiffness of fractures on the constitutive relationship of the medium can be *** relative three-dimensional program of finite element method was also *** comparing with the existing computation example,reliability of the model and the program were *** a hypothetical nuclear waste repository as a calculation example,the radioactive nuclide leak was simulated numerically with both the rock mass and the buffer being unsaturated media,and the temperatures,negative pore pressures,flow velocities,nuclide concentrations and normal stresses in the rock mass were *** results showed that the temperatures,negative pore pressures and nuclide concentrations in the buffer all present nonlinear changes and distributions that even though the saturation degree in porosity is only about 1/9 of that in fracture,the flow velocity of underground water in fracture is about 6 times of that in porosity because the permeability coefficient of fracture is almost four orders higher than that of porosity,and that the regions of stress concentration occur at the vicinity of two sides of the boundary between buffer and disposal pit wall.

关键词： dual-porosity medium thermo-hydro-mechanical-migratory coupling three-dimensional model FEM analysis

Lake sediments from Dianchi Lake:A Phosphorus sink or source?

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Pedosphere 2004年第4期14卷 483-490页

作者： GAOLi YANGHao ZHOUJian-Min LüJun-Jie stateKeyLaboratoryofsoilandsustainableAgriculture InstituteofSoilScienceChineseAcademyofSciencesNanjing210008（China）.

Dianchi Lake is a highly eutrophic lake in southwestern china where phosphorus (P) is the limiting element for eutrophication and where lake sediments play an important role in the P cycle. One hundred and eighteen sites were sampled throughout Dianchi Lake in 2002 to investigate the P loading of the lake sediments, while fresh surface sediments were studied in the laboratory to clarify its role for phosphorus. The results showed that concentrations of total phosphorus (TP) in sediments were very high, with a maximum value of 6.66 g kg-1, and decreased with sediment depth. P adsorption on surface sediments was rapid with adsorption amounts higher in acidic than in alkaline conditions. The release experiments showed that P release increased as pH rose from 7.0 to 10.5. Additionally, compared with aerobic conditions, P release was much higher under anaerobic conditions, especially with low P content in the lake water. At present, the sediments in Dianchi Lake still function as a sink for phosphorus at high P levels in lake water. However, if the external P load was reduced and P content in lake water became low, the sediment would have a large potential for P release under anaerobic conditions.

关键词： adsorption Dianchi Lake phosphorus release sediment

Classification of Ferrallitic soils in chinese soil Taxonomy

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Pedosphere 2000年第2期10卷 125-133页

作者： GONG ZITONG CHEN ZHICHENG ZHAO WENJUN and sHI HUA(institute of soil science, the {3. academy of sciences, P.O. Box 821, Naroing 21.008 china) 中科院南京土壤所江苏南京 210008

The development of the classification of ferrallitic soils in china is reviewed and the classification ofFerralisols and Ferrisols in chinese soil Taxonomy is introduced in order to discuss the correlation betweenthe ferrallitic soil classification in the chinese soil Taxonomy and those of the other soil classification *** the former soil classification systems of china, the ferrallitic soils were classified into the soil groups ofLatosols, Latosolic red soils, Red soils, Yellow soils and Dry red soils, according to the combination of soilforming conditions, soil-forming processes, soil features and soil properties. In the chinese soil Taxonomy,most of ferrallitic soils are classified into the soil orders of Ferralisols and Ferrisols based on the diagnostichorizons and/or diagnostic characteristics with quantitatively defined properties. Ferralisols are the soilsthat have ferralic horizon, and they are merely subdivided into one suborder and two soil groups. Ferrisolsare the soils that have LAC-ferric horizon but do not have ferralic horizon, and they are subdivided intothree suborders and eleven soil groups. Ferralisols may correspond to part of Latosols and Latosolic red *** may either correspond to part of Red soils, Yellow soils and Dry red soils, or correspond to part ofLatosols and Latosolic red soils.

关键词： Ferralisols Ferrisols chinese soil Taxonomy

The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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science china Earth sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2, CAI Qiangguo1, YUE Zhongqi3. LU Zhongchen4, LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land surface Processes, institute of Geographic {1.s and Natural Resources Re-search, chinese {3. of {1.s, Beijing 100101, china 2. institute of Forestry, chinese {3. of Forestry {1.s, Beijing 100091, china 3. Department of Civil Engineering, University of Hong Kong, Hong Kong, china 4. Eco-environmental Research Center, chinese {3. of {1.s, Beijing 100085, china 5. College of Resources and Environment, southwest Agricultural University, Chongqing 400716, china Correspondence should be addressed to Chen Hao 1. Key Laboratory of Water Cycle and Related Land surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. institute of Forestry Chinese Academy of Forestry Sciences 100091 Beijing China 3. Department of Civil Engineering University of Hong Kong Hong Kong China 4. Eco-environmental Research Center Chinese Academy of Sciences 100085 Beijing China 5. College of Resources and Environment Southwest Agricultural University 400716 Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 53. mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4% less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2, it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 3.%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.