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Denitrification Losses and N_2O Emissions from Nitrogen Fertilizer Applied to a Vegetable Field

Pedosphere 2006年第3期16卷 390-397页

作者： CAO Bing He Fa-Yun Xu Qiu-Ming Yin Bin CAI Gui-Xin State Key laboratory of soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Graduate School of the chinese academy of sciences Beijing 100039 （China） institute of Plant Nutrition and Resources Beijing Academy of Agricultural and Forestry Sciences Beijing 100089 （China）

A field experiment was conducted on chinese cabbage （Brassica campestris L. ssp. pekinensis （Lour.） Olsson） in a Nanjing suburb in 2003. The experiment included 4 treatments in a randomized complete block design with 3 replicates： zero chemical fertilizer N （CK）; urea at rates of 300 kg N ha^-1 （U300） and 600 kg N ha^-1 （U600）, both as basal and two topdressings; and polymer-coated urea at a rate of 180 kg N ha^-1 （PCU180） as a basal application. The acetylene inhibition technique was used to measure denitrification （N2 ＋ N2O） from intact soil cores and N2O emissions in the absence of acetylene. Results showed that compared to （3K total denitrification losses were significantly greater （P ≤ 0.05） in the PCU180, U300, and U600 treatments,while N2O emissions in the U300 and U600 treatments were significantly higher （P ≤ 0.05） than （3K. In the U300 and U600 treatments peaks of denitrification and N2O emission were usually observed after N application. In the polymer-coated urea treatment （PCU180） during the period 20 to 40 days after transplanting, higher denitrification rates and N2O fluxes occurred. Compared with urea, polymer-coated urea did not show any effect on reducing denitrification losses and N2O emissions in terms of percentage of applied N. As temperature gradually decreased from transplanting to harvest, denitrification rates and N2O emissions tended to decrease. A significant （P ≤0.01） positive correlation occurred between denitrification （r = 0.872） or N2O emission （r = 0.781） flux densities and soil temperature in the CK treatment with a stable nitrate content during the whole growing season.

关键词： denitrification loss N2O emission polymer-coated urea urea vegetable field

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EFFECT OF SENSOR ARRAY GEOMETRY ON MICROSEISMIC SOURCE LOCATION ALGORITHMS

EFFECT OF SENSOR ARRAY GEOMETRY ON MICROSEISMIC SOURCE LOCAT...

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The 7th International Symposium on rockburst and Seismicity in Mines(RaSiM7)

作者： BING-RUI CHEN,XIA-TING FENG State Key Laboratory of Geomechanics and Geotechnical Engineering,institute of rock and soil mechanics,the chinese academy of sciences,wuhan 430071,P.R.china

The algorithms of source location can be classified into four classes in terms of required solved parameters theoretically:firstly,velocity structure is given,and locations of microseismic sources and time of microseismic occurrence are identified on basis of arrival time recorded;secondly,given locations of microseismic sources, velocity structure and time of microseismic occurrence are solved in terms of arrival time;thirdly,velocity structure and locations of microseismic sources are inversed based on the time difference of sensor-pairs;lastly,velocity structure,locations of microseismic sources and time of microseismic occurrence are recognized together based on arrival *** effect of sensor array geometry on the four algorithms of source location is studied systematacially. Studies show that velocity of convergence is faster and precision of convergence is higher in ranges of sensor array than out of sensor array for the first algorithm;if only sensors can receive microseismic signals,the solution is unique and sensor locations are unlimited theoretically for the second conditions;the same association characteristics are found for the last two algorithms by theoretical analysis and the necessary condition that the association occurs, isΔL/V=Δ*** to improve precision of source location,the different algorithms should adopt different strategy for acquiring good sensor array geometry.

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Relationship between precipitation and the infiltration depth over the middle and lower reaches of the Yellow River and Yangtze-Huaihe River Valley

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Progress in Natural Science:Materials International 2008年第9期18卷 1123-1128页

作者： Zhixin Hao a, Jingyun Zheng a, Quansheng Gea,, Xifeng Guoa,b a institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, 11A, Datun Road Anwai, Chaoyang District, Beijing 100101, china b Graduate University of chinese academy of sciences, Beijing 100049, china institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences 11A Datun Road Anwai Chaoyang District Beijing 100101 China Graduate University of chinese academy of sciences Beijing 100049 China

The purpose of the paper is to extract and make the best use of rainfall information contained in the chinese historical archives of Qing Dynasty, and reconstruct the precipitation series during *** study followed the Yu-Fen-Cun (rainfall infiltration depth) observation method in Qing Dynasty, to conduct soil infiltration experiment under the natural rainfall conditions during *** related parameters, such as precipitation, intensity, initial soil moisture content and infiltration depth have been measured at 10 stations (east of 105°E, 30°-40°N) with representative climatic conditions and soil physical texture in the middle and lower reaches of the Yellow River and Yangtze-Huaihe River *** statistical results indicate that precipitation is the primary infiuencing factor to infiltration depth and is positively correlated with the infiltration ***, the efiects of every factor on infiltration depth are significantly difierent between the middle and lower reaches of the Yellow River and Yangtze-Huaihe River ***, the relationship equations of precipitation and infiltration depth are established for each site, most of which can pass over 60% of the variance explanations and provide quantitative models to reconstruct the precipitation series using Yu-Fen-Cun records in Qing Dynasty.

关键词： Middle and lower reaches of the Yellow River and Yangtze-Huaihe River Valley Precipitation Infiltration depth Yu-Fen-Cun Climate reconstruction

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In situ experiments on width and evolution characteristics of excavation damaged zone in deeply buried tunnels

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Science china(Technological sciences) 2011年第S1期54卷 167-174页

作者： LI ShaoJun 1,FENG XiaTing 1,LI ZhanHai 3,CHEN BingRui 1,JIANG Quan 1,WU ShiYong 2,HU Bin 2 &XU JinSong 2 1 State Key Laboratory of Geomechanics and Geotechinical Engineering,institute of rock and soil mechanics,chinese academy of sciences,wuhan 430071,china 2 Ertan Hydropower Development Company,Ltd.,Chengdu 610051,china 3 School of Resources and Civil Engineering,Northeastern University,Shenyang 110004,china 1. State Key Laboratory of Geomechanics and Geotechinical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China3. School of Resources and Civil Engineering Northeastern University Shenyang 110004 China2. Ertan Hydropower Development Company Ltd. Chengdu 610051 China

The seven long tunnels of Jinping II hydropower station are deeply *** width and evolution characteristics of excavation damaged zone(EDZ) are the key problem to the design of tunnels excavation and *** order to study this problem,several specific experimental tunnels with different overburden and geometric sizes were excavated at this *** borehole camera,sliding micrometer,cross-hole acoustic wave equipment and acoustic emission apparatus were *** paper introduced the comprehensive in situ experimental methods through pre-installed facilities and pre-drilled *** properties of the surrounding rock mass,including cracks,deformation,elastic wave and micro fractures,were measured during the whole process of the tunnel *** width and characteristics of formation and evolution of tunnels EDZ were analyzed under different construction methods involving of TBM and drilling and blasting,the test tunnels were excavated by full-face or two *** relationships between EDZ and tunnel geometry sizes,overburden and excavation method were described as *** results will not only contribute a great deal to the analysis of rock mass behavior in deeply buried rock mass,but also provide direct data for support design and rockburst prediction.

关键词： deeply buried tunnel excavation damaged zone evolution characteristics in situ experiments

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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 chinese academy of sciences, P. O. Box 821, Nanjing 210008 (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 35 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

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Phenolic Acids in Plant-soil-Microbe System: A Review

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Pedosphere 2002年第1期12卷 1-14页

作者： LI SHOUTIAN, ZHOU JIANMIN, WANG HUOYAN and CHEN XIAOQIN institute of soil Science, the chinese academy of sciences, P. O. Box 821, Nanjing S10008 (china) institute of soil Science the Chinese Academy of Sciences P. O. Box 821 Nanjing 210008

Phenolic acids are very common compounds in pedosphere. Theobjective of this review was to summarize the current knowledge ofthe behaviors of phenolic acids in plant-soil microbe system. Whenphenolic acids originated form leaching, decomposition and exudationof living and dead plant tissues enter soils, they can reactphysiochemically with soil particle surfaces and/or incorporate intohumic matter. Phenolic acids desorbed from soil particle surfaces andremained in solution phase can be utilized by microbe as carbonsources and absorbed by plants.

关键词： allelopathic activity phenlic acids plant-soil-microbe system

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Methane Emission from Natural Wetlands in china:Summary of Years 1995-2004 Studies

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Pedosphere 2007年第4期17卷 475-486页

作者： DING Wei-Xin CAI Zu-Cong State Key Laboratory of soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）.

From studies undertaken during 1995-2004, annual budgets of CH4 emissions from natural wetlands and its temporal and spatial variations were examined throughout china, and various factors influencing CH4 emissions were also evaluated. The seasonal variation in CH4 emissions that increased with increasing plant growth reached its peak in August; decrease in the emissions was found in freshwater marshes but not in peatlands. Emissions were mainly controlled by temperature and depth of standing water. Low CH4 emissions at the early plant growing stages were not because of deficiency of organic C for CH4 production but because of low temperatures. Low temperatures not only reduced CH4 production but also stimulated CH4 oxidation by lowering the activity of other aerobic microbes which left more 02 in the rhizosphere for methanotrophs. Low summer temperatures （below 20 ℃） in the Qinghai-Tibetan Plateau lowered CH4 production and CH4 emission resulting in little or no seasonal variation of emissions. Diel and spatial variation in CH4 emissions depended on plant species. For plants that transport CH4 using the pressure-driven convective through-flow mechanism, diel variation in CH4 emissions was governed by diel variation of solar energy load （that produces temperature and vapor pressure differences within various plant tissues） and stomatal conductance. For plants that transport gases using the molecular diffusion mechanism only, the diel variation of CH4 emissions was because of differences in the magnitude of O2 produced through photosynthesis and then delivered into the rhizomes and/or rhizosphere for CH4 oxidation. Emergent plants could transport more CH4 than submerged plants because the former transport CH4 directly into the atmosphere rather than into water as do submerged plants where CH4 can be further be oxidized during its diffusion from water to the atmosphere. Emergent plants with high gas transport capacity could not only transport more CH4 into the atmosphe

关键词： diel variation methane emission seasonal variation temporal variation wetland

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Initiation and Development of Water Film by Seepage

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Journal of Mountain Science 2010年第4期7卷 361-366页

作者： LU Xiaobing CUI Peng HU Kaiheng ZHANG Xuhui institute of mechanics Chinese Academy of Sciences Beijing 100080 China institute of Mountain Hazards & Environment Chinese Academy of Sciences Chengdu 610041 China

When water seeps upwards through a saturated soil layer,the soil layer may become instability and water films occur and *** film serves as a natural sliding surface because of its very small ***,debris flow may *** investigate this phenomenon,a pseudothree-phase media is presented *** discontinuity method is used to analyze the expansion velocity of water ***,perturbation method is used to analyze the case that a water flow is forced to seep upwards through the soil layer while the movement of the skeleton may be neglected relative to that of *** theoretical evolutions of pore pressure gradient,effective stress,water velocity,the porosity and the eroded fine grains are *** can be seen clearly that with the erosion and redeposited of fine grains,permeability at some positions in the soil layer becomes smaller and smaller and,the pore pressure gradient becomes bigger and bigger,while the effective stress becomes smaller and *** the effective stress equals zero,***,the water film *** is shown also that once a water film occurs,it will be expanded in a speed of U(t)(1-ε).

关键词： Slope Seepage Debris flow Water film

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Effect of Groundwater Irrigation on soil PAHs Pollution Abatement and soil Microbial Characteristics:A Case Study in Northeast china

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Pedosphere 2010年第5期20卷 557-567页

作者： ZHANG Jing ZHANG Hui-Wen ZHANG Cheng-Gang institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 (China) State Key Laboratory of soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China)

To evaluate the effect of groundwater irrigation on the polycyclic aromatic hydrocarbons(PAHs) pollution abatement and soil microbial characteristics,a case study was performed in the Shenfu irrigation area of Shenyang,Northeast china,where the irrigation with petroleum wastewater had lasted for more than fifty years,and then groundwater irrigation instead of wastewater irrigation was applied due to the gradually serious PAHs pollution in *** chemical properties,including PAHs and nutrients contents,and soil microbial characteristics,including microbial biomass carbon,substrateinduced respiration,microbial quotient(qM),metabolic quotient(qCO2),dehydrogenase(DH),polyphenol oxidase(PO),urease(UR) and cellulase(CE) in surface and subsurface were *** organic C,total N,total P,and available K were significantly different between the sites *** PAHs concentrations ranged from 610.9 to 6362.8 μg kg-1 in the surface layers(0-20 cm) and from 404.6 to 4318.5 μg kg-1 in the subsurface layers(20-40 cm).From the principal component analysis,the first principal component was primarily weighed by total PAHs,total organic C,total N,total P and available K,and it was the main factor that influencing the soil microbial *** the tested microbial characteristics,DH,PO,UR,CE,qM and qCO2 were more sensitive to the PAHs stress than the others,thus they could serve as useful ecological assessment indicators for soil PAHs pollution.

关键词： microbial biomass paddy soil polycyclic aromatic hydrocarbons soil enzyme activities

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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 chinese academy of sciences, P.O. Box 821, Nanjing 210008 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

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