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Pedosphere 2011年第2期21卷 178-185页

作者： LI Zhi-Guo Key Laboratory of Oasis Ecology and Desert Environment Xinjiang Institute of Ecology and Geography Chinese Academy ofSciences Urumqi 830011 (China) Graduate University of chinese Academy of sciences Beijing 100049 (China) institute of soil {2. Chinese Academy of Sciences Nanjing 210008 (China) Earth System science Interdisciplinary Center University of Maryland College Park MD 20740 (USA)

In northwestern china, there has been a change from traditional cultivation system （TC） with no mulching and flood irrigation to a more modern cultivation system （MC） using plastic film mulching with drip irrigation. A field study was conducted to compare soil ＇C02.concentrations and soil surface COs fluxes between TC and MC systems during a cotton growing season. CO2.concentrations in the soil profile were higher in the MC system （3.07-92.2.L L-1） than in the TC system （1 2.5-8994 μL L-1） but the rate of CO2.flux was lower in the MC system. Possible reasons for this included decreased gas diffusion and higher soil moisture due to the mulching cover in the MC system, and the consumption of soil CO2.by weathering reactions. Over the whole cotton growing season, accumulated rates of CO2.flux were 3.0 and 3.4 g C m-2.for the MC and TC systems, respectively. When agricultural practices were converted from traditional cultivation to a plastic film mulching system, soil CO2.emissions could be reduced by approximately 100 g C m-2.year-1 in agricultural lands in arid and/or semi-arid areas of northern and northwestern china.

关键词： agricultural practice carbon cycle greenhouse gas emission soil respiration weathering reaction

Erosion response to anthropogenic activity and climatic changes during the Holocene: case studies in northwestern china and southern Norway

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Journal of Geographical sciences 2002年第4期12卷 467-471页

作者： HE Xiubin1,2. TANG Keli1, John A Matthews3. Geraint Owen3.1. {2. of soil and Water Conservation, CAS, Yangling 712.00, china 2. Northwest SCI-Tech University of Agriculture and Forestry, Yangling 712.00, china 3. Department of Geography, Univer institute of soil and Water Conservation CAS Yangling China Northwest SCI-Tech University of Agriculture and Forestry Yangling China Department of Geography University of Wales Swansea UK

soil erosion assessment and prediction play critical roles in addressing problems associated with erosion control or soil conservation. The past dynamics of soil erosion can provide valuable information for us to understand the relations of soil erosion to environmental change and anthropogenic activity. The present paper has compared Holocene climatic changes in northwestern china with those in southern Norway, and investigated the past dynamics of erosion activity during the Holocene. Modern soil erosion on the Loess Plateau is a combination of the intensive natural erosion and human-induced erosion, the latter being four times greater than the former. Because of global warming and increasing human activities, climate on the Loess Plateau is becoming dryer and more unstable, causing an enhanced erosion problem and water scarcity. In the arctic-alpine region of southern Norway, however, the global warming and regional wetting caused expansion of the largest European ice cap. This has accentuated the erosion in that region, with a higher frequency of avalanches and debris flows.

关键词： anthropogenic activity china climate changes erosion response Norway

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 {2.s and Natural Resources Re-search, chinese Academy of {2.s, Beijing 100101, china 2. institute of Forestry, chinese Academy of Forestry {2.s, Beijing 100091, china 3. Department of Civil Engineering, University of Hong Kong, Hong Kong, china 4. Eco-environmental Research Center, chinese Academy of {2.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 {2. 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.

Validation of three infiltration models on purple soil under simulated rainfall

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Progress in Natural science:Materials International 2007年第9期17卷 1059-1066页

作者： Wang Yukuan1,2.Fu Bin1,3.Xu Pei1,2.Wang Daojie1,2.Wang Xiantuo1,3.and Wang Yongqiang1,3.1.Key Laboratory of Mountain Surface Process and Hazards,chinese Academy of Seiences,Chengdu 610041,china 2.institute of Mountain Hazards and Environment,chinese Academy of sciences,Chengdu 610041,china 3.Graduate University of the chinese Academy of sciences,Beijing 100049,china) Key Laboratory of Mountain Surface Process and Hazards Chinese Academy of Seiences Chengdu 610041 China institute of Mountain Hazards and Environment， chinese Academy of {2.s， Chengdu 610041 China Graduate University of the chinese Academy of sciences Beijing 100049 China

So as to find models suitable for the prediction of water infiltration in purple soil,infiltration rates simulated by three popular empirical infiltration models,Horton model,Kostiakov model,and the modified Kostiakov model,were compared by using those observed results on slope in purple soil under rainfall simulation.2. sets of infiltration data were divided into two parts for parameter estimation and validation *** performance of the three infiltration models was evaluated with the Nash and Sutcliffe efficiency *** results show that the percent for Nash and Sutcliffe efficiency greater than 0.7 is about 69.7% for the Horton model,and 48.48%,and 54.55% for the Kostiakov model and the modified Kostiakov model,*** model is better than Kostiakov model and the modified Kostiakov model in most rain events in the ***,Kostiakov model is still suitable for reasonable prediction of the infiltration in purple soil sloping farmland because fewer parameters are ***,rainfall intensity has significant effects on the parameter values used in the simulation *** simulation results can be improved by choosing suitable parameters according to the rainfall intensity.

关键词： infiltration model sloping farmland purple soil rainfall simulation

A new elliptic-parabolic yield surface model revised by an adaptive criterion for granular soils

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science china(Technological sciences) 2010年第8期53卷 2152-2159页

作者： LIU HanLong 1,2.,XIAO Yang 1,2.,LIU JinYuan 3.&LI GuoYing 4 1 Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering,Hohai University, nanjing 2.0098,{2. 2.Geotechnical Research institute,Hohai University,nanjing 2.0098,{2. 3.epartment of Civil Engineering,Ryerson University,Toronto,Canada 4 Department of Geotechnical Engineering,nanjing Hydraulic Research institute,nanjing 2.0014,{2. 1. Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai University Nanjing 210098 China2. Geotechnical Research Institute Hohai University Nanjing 210098 China3. Department of Civil Engineering Ryerson University Toronto Canada4. Department of Geotechnical Engineering Nanjing Hydraulic Research Institute Nanjing 210014 China

An adaptive criterion for shear yielding as well as shear failure of soils is proposed in this paper to address the fact that most criteria,including the Mohr-Coulomb criterion,the Lade criterion and the Matsuoka-Nakai criterion,cannot agree well with the experimental results when the value of the intermediate principal stress parameter is too *** new criterion can adjust an adaptive parameter based on the experimental results in order to make the theoretical calculations fit the test results more *** original elliptic-parabolic yield surface model can capture both soil contraction and dilation ***,it normally over-predicts the soil strength due to its application of the Extended Mises criterion.A new elliptic-parabolic yield surface mode is presented in this paper,which introduces the adaptive criterion in three-dimensional principal stress *** new model can well model the stress-strain behavior of soils under general stress *** to the original model which can only simulate soil behavior under triaxial compression conditions,the new model can simulate soil behaviors under both triaxial compression conditions and general stress conditions.

关键词： principal stress space intermediate principal stress yield surface failure criterion constitutive model

Comparison of Extraction Techniques with Different Solvents for DDT Analogues in Sediments

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Pedosphere 2005年第5期15卷 628-633页

作者： LANG Yin-Hai JIANG Xin D. MARTENS ZHAO Qi-Guo College of Environmental science and Engineering Ocean University of China Qingdao 266003 （China） institute of soil {2. Chinese Academy of Sciences Nanjing 210008 （China） institute of Ecological Chemistry GSF-National Research Center for Environment and HeaLth Neuherberg 85764（Germany）

Four techniques, Soxhlet extraction (SOX), ultrasonic extraction (USE), fluidized-bed extraction (FBE) and acce-lerated solvent extraction (ASE) with different solvents (methanol, hexane/acetone and acetonitrile) were used for theextraction of DDT analogues in sediments. Results revealed that the four extraction techniques had high recoveries (>86.0%) with low standard deviations (2.0%) for most of DDT analogues, meaning that they could all successfully extractDDT analogues in sediments. Accelerated solvent extraction using methanol and hexane/acetone (1:1), fluidized-bedextraction using hexane/acetone (1:1) and the ultrasonic extraction using hexane/acetone (1:1) were comparable or betterthan Soxhlet extraction using hexane/acetone (1:1). Considering solvent- and time-consumption, level of automation,and environmental risk, accelerated solvent extraction with hexane/acetone (1:1) was better than the other extractiontechniques.

关键词： DDT analogues extraction techniques sediment solvents

Anomaly feature of seasonal frozen soil variationson the Qinghai-Tibet Plateau

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Journal of Geographical sciences 2002年第1期12卷 99-107页

作者： WANG Cheng-hai1,2. DONG Wen-jie3. WEI Zhi-gang2.(1. College of Resource and Environmental science, Lanzhou University, Lanzhou 73.000, china 2. Cold and Arid Regions Environmental and Engineering Research institute, CAS, Lanzhou 73.000, china 3. Insti College of Resource and Environmental science Lanzhou University Lanzhou 730000 Cold and Arid Regions Environmental and Engineering Research institute CAS Lanzhou 730000 institute of Atmospheric Physics CAS 北京 Beijing

The seasonal frozen soil on the Qinghai-Tibet Plateau has strong response to climate change, and its freezing-thawing process also affects East Asia climate. In this paper, the freezing soil maximum depth of 46 stations covering 1961–1999 on the plateau is analyzed by rotated experience orthogonal function (REOF). The results show that there are four main frozen anomaly regions on the plateau, i.e., the northeastern, southeastern and southern parts of the plateau and Qaidam Basin. The freezing soil depths of the annual anomaly regions in the above representative stations show that there are different changing trends. The main trend, except for the Qaidam Basin, has been decreasing since the 1980s, a sign of the climate warming. Compared with the 1980s, on the average, the maximum soil depth decreased by about 0.02.m, 0.05 m and 0.14 m in the northeastern, southeastern and southern parts of the plateau, but increased by about 0.57 m in the Qaidam Basin during the 1990s. It means there are different responses to climate system in the above areas. The spectrum analysis reveals different change cycles: in higher frequency there is an about 2.year long cycle in Qaidam Basin and southern part of the plateau in the four representative areas whereas in lower frequency there is an about 14-year long cycle in all the four representative areas due to the combined influence of different soil textures and solutes in four areas.

关键词： Qinghai-Tibet Plateau seasonal frozen soil rotated empirical orthogonal function analysis anomaly areas

Changes in soil C and N Contents and Mineralization Across a Cultivation Chronosequence of Paddy Fields in Subtropical china

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Pedosphere 2005年第5期15卷 554-562页

作者： LI Zhong-Pei ZHANG Tao-Lin HAN Feng-Xiang P. FELIX-HENNINGSEN institute of soil {2. Chinese Academy of Sciences Nanjing 210008 （China） Diagnostic Instrumentation and Analysis Laboratory Mississippi State University Starkville MS 39759 （USA） institute of soil {2. and soil Conservation Justus-Liebig-University Giessen D-35392 （Germany）

Dynamics of soil organic matter in a cultivation chronosequence of paddy fields were studied in subtropical *** of soil organic matter was determined by measuring CO2.evolution from soil during 2. days of laboratoryincubation. In the first 3. years of cultivation, soil organic C and N contents increased rapidly. After 3. years, 0-10 cmsoil contained 19.6 g kg-1 organic C and 1.62.g kg-1 total N, with the corresponding values of 18.1 g kg-1 and 1.50g kg-1 for 10-2. cm, and then remained stable even after 80 years of rice cultivation. During 2. days incubation themineralization rates of organic C and N in surface soil (0-10 cm) ranged from 2.2. to 3.3. and from 2.8% to 6.7%,respectively, of organic C and total N contents. Biologically active C size generally increased with increasing soil organicC and N contents. soil dissolved organic C decreased after cultivation of wasteland to 10 years paddy field and thenincreased. soil microbial biomass C increased with number of years under cultivation, while soil microbial biomass Nincreased during the first 3. years of cultivation and then stabilized. After 3. years of cultivation surface soil (0-10 cm)contained 3.2.8 mg kg-1 of microbial biomass C and 2.3}85 mg kg-1 of microbial biomass N, which were 111% and 47%higher than those in soil cultivated for 3.years. It was suggested that surface soil with 3. years of rice cultivation insubtropical{13. would have attained a steady state of organic C content, being about 19 g kg-1.

关键词： cultivation chronosequence mineralization paddy fields soil C soil N

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

Virtual multi-dimensional internal bonds model and its application in simulation of rock mass

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science china(Technological sciences) 2008年第2期51卷 192-201页

作者： ZHANG ZhenNan1,2.& GE XiuRun3.4 1 Department of Civil Engineering,Shanghai University,Shanghai 2.0072.china 2.Shanghai {2. of Applied Mathematics and Mechanics,Shanghai University,Shanghai 2.0072. china 3.{2. of Geotechnical Engineering,Shanghai Jiao Tong University,Shanghai 2.003.,china 4 {2. of Rock and soil Mechanics,chinese Academy of sciences,Wuhan 43.071,china 1. Department of Civil Engineering Shanghai University Shanghai 200072 China 2. Shanghai institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China 3. institute of Geotechnical Engineering Shanghai Jiao Tong University Shanghai 200030 China 4. institute of Rock and soil Mechanics Chinese Academy of Sciences Wuhan 430071 China

VMIB (virtual multi-dimensional internal bonds) is a multiscale mechanical model developed from the VIB (virtual internal bond) theory. In VIB theory,the solid mate-rial is considered to consist of random-distributed material particles in microscale. These particles are connected with normal bonds. The macro constitutive relation is derived from the cohesive law between particles. However,in VMIB,the micro particles are connected with both normal and shear bonds. The macro constitutive relation is derived in terms of bond stiffness coefficients. It has been theoretically certified that there exists a corresponding relationship between the two bond stiffness coefficients and the two macro material constants,i.e. the Young’s modulus and Poisson ratio. This corresponding relationship suggests that it should be necessary and sufficient to simultaneously account for the normal and shear interactions between particles. Due to the fact that the fracture criterion is directly incorporated into the constitutive relation,both VIB and VMIB present many advantages in simulating fractures of materials. In the damage model of rock mass,a damage tensor is usually defined to describe the distribution of cracks. The damage value in one direction determines the relative stiffness of rock mass in this direction. In VMIB solid,the relative distribution density of micro bonds in one direction determines the relative macro stiffness of the material in this direction. The effects of the damage value and the relative distribution density of bonds are consistent. To simulate the failure behavior of rock mass with VMIB,the presented paper sets up a quantitative relationship between the damage tensor and the rela-tive distribution density of bonds. Comparison of the theoretical and the experi-mental results shows that VMIB model can represent the effect of distributed cracks on rock mass with this relationship. The presented work provides a founda-tion for further simulating fracture behavior

关键词： VMIB (virtual multi-dimensional internal bonds) rock mass VIB (virtual internal bonds) multi-cracked body numerical simulation