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Crop residue incorporation and nitrogen fertilizer effects on greenhouse gas emissions from a subtropical rice system in Southwest China

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Journal of Mountain Science 2018年第9期15卷 1972-1986页

作者： wang xiao-guo LUO Yong Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and Environment Chinese Academy of Sciences Key laboratory of Geological Spatial information Technology of Ministry of Land and Resource Chengdu University of Technology

Crop residue incorporation has been widely accepted as a way to increase soil carbon(C) sequestration and sustain soil fertility in agroecosystems. However, effect of crop residue incorporation on greenhouse gas(GHG) emissions in rice paddy soils remains uncertain. A field experiment was conducted to quantify emissions of CH_4 and N_2O and soil heterotrophic respiration(RH) from a paddy rice field under five different crop residue treatments(i.e., 150 kg N ha^(-1) of synthetic N fertilizer application only [NF], 150kg N ha^(-1) of synthetic N fertilizer plus 5.3 Mg ha^(-1) wheat residue [NF-WR1], 150 kg N ha^(-1) of synthetic N fertilizer plus 10.6 Mg ha^(-1) wheat residue [NF-WR2], 75 kg N ha^(-1) of synthetic N fertilizer plus 10.6 Mg ha^(-1) wheat residue [50%NF-WR2] and 150 kg N ha^(-1) of synthetic N fertilizer plus 21.2 Mg ha^(-1) wheat residue [NF-WR3]) in southwest China. Our results showed that crop residue incorporation treatments(NF-WR1, NF-WR2, 50%NF-WR2, NF-WR3) significantly increased CH_4 emissions by at least 60%, but N_2O emissions were not enhanced and even suppressed by 25% in the NF-WR3 treatment as compared to the NF treatment. Soil RH emissions were comparable among experimental treatments, while crop residue incorporation treatments significantly increased soil carbon sequestrations relative to the NF treatment. Overall, CH_4 emissions dominated total global warming potentials(GWP) across all experimental treatments. The average yieldscaled GWPs for the NF and NF-WR1 treatments were significantly lower than for the NF-WR2, 50%NFWR2 and NF-WR3 treatments. Given the comparable yield-scaled GWPs between the NF and NF-WR1 treatments, the NF-WR1 treatment could gain net carbon sequestration as compared with the NF treatment with net soil carbon loss. Our findings suggest that the NF-WR1 treatment should be an effective option to sustain rice production while mitigating GHG emissions from the rice field in China.

关键词： Methane Nitrous oxide Crop residueSoil carbon sequestration Global warming potentialPaddy field

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Prediction of Toxicity of Phenols and Anilines to Algae by Quantitative Structure-activity Relationship

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Biomedical and Environmental Sciences 2008年第3期21卷 193-196页

作者： GUANG-HUA LU CHAO wang xiao-LING guo State Key Laboratory for Hydrology-water Resources and Hydraulic Engineering College of Environmental Science and Engineering Hohai University Nanjing 210098 Jiangsu China

Objective To measure the toxicity of phenol, aniline, and their derivatives to algae and to assess, model, and predict the toxicity using quantitative structure-activity relationship （QSAR） method. Methods Oxygen production was used as the response endpoint for assessing the toxic effects of chemicals on algal photosynthesis. The energy of the lowest unoccupied molecular orbital （ELUMO） and the energy of the highest occupied molecular orbital （EHOMO） were obtained from the ChemOffice 2004 program using the quantum chemical method MOPAC, and the frontier orbital energy gap （△E） was obtained. Results The compounds exhibited a reasonably wide range of algal toxicity. The most toxic compound was α-naphthol, whereas the least toxic one was aniline. A two-descriptor model was derived from the algal toxicity and structural parameters： logl/EC50=0.2681ogKow-1.006△E＋11.769 （n=20, r^2=0.946）. This model was stable and satisfactory for predicting toxicity. Conclusion Phenol, aniline, and their derivatives are polar narcotics. Their toxicity is greater than estimated by hydrophobicity only, and addition of the frontier orbital energy gap AE can significantly improve the prediction of logKow-dependent models.

关键词： Toxicity QSARs Frontier orbital energy gap Prediction

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Synthesis and Crystal Structure of N-[4-(4-Methyl-phenylsulfamoyl)-phenyl]- 4-methyl-1,2,3-thiadiazole-5-carboxamide

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Chinese Journal of Structural Chemistry 2007年第5期26卷 501-504页

作者： wang Jian-guo xiao Yong-Jun Li Zheng-Ming SONG Hai-Bin （Elemento-organic Chemistry hlstitute State Key Laboratory ofElemento-organic Chemistry Nankai University Tianjin 300071 China

The crystal structure of the title compound （C17H16N4O3S2, Mr = 388.46） has been determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c with a = 13.688（2）, b = 16.704（3）, c = 8.3308（12）A, β = 99.474（6）°, V = 1878.8（5） A^3, Mr = 388.46, Z = 4, Dc = 1.373 g/cm3, μ = 0.308 mm^–1, F（000） = 808, R = 0.0389 and wR = 0.0917. X-ray analysis reveals that the crystal structure involves intermolecular N–H…O and N–H…N hydrogen bonds, which link the molecules into a layer parallel to the ac plane.

关键词： X-ray diffraction crystal structure synthesis

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Assessment of Soil Organic Carbon Stock in the Upper Yangtze River Basin

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Journal of Mountain Science 2013年第5期10卷 866-872页

作者： wang xiao-guo ZHU Bo HUA Ke-ke LUO Yong ZHANG Jian ZHANG An-bang Key Laboratory of Mountain Surface Processes and Ecological Regulation Chinese Academy of Sciences Henan Institute of Science and Technology

Soil organic carbon is of great importance to terrestrial ecosystems. Studies on the amount and spatial distribution of soil organic carbon stock in various types of soil can help to better understand the role of soil in the global carbon cycle and provide a scientific basis for the assessment of the magnitude of carbon stored in a given area. Here we present estimates of soil organic carbon stock in soils in the upper reaches of the Yangtze River based on soil types as defined by Chinese Soil Taxonomy and recently compiled into a digital soil database. The results showed that the total soil organic carbon stock of the upper Yangtze River to a depth of 100 cm was 1.452x1013 kg. The highest soil organic carbon stock was found in felty soils （2.419x10TM kg）, followed by dark brown soils （1.269x10=kg）, and dark feltysoils （L139x10=kg）. Chernozems and irrigation silting soils showed the lowest soil organic carbon stock, mainly due to the small total area of such soils. The soil organic carbon density of these major soil types ranged from 5.6 to 26.1 kg m2- The average soil organic carbon density of the upper reaches of the Yangtze River was 16.4 kg m-2, which was higher than that of the national average. Soil organic carbon density indicated a distinct decreasing trend from west to east, which corresponds to the pattern of increasing temperature from cold to subtropical.

关键词： Soil Organic carbon Carbon stock YangtzeRiver

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The impact of nitrogen amendment and crop growth on dissolved organic carbon in soil solution

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Journal of Mountain Science 2016年第1期13卷 95-103页

作者： wang xiao-guo LI Chang-sheng LUO Yong HUA Ke-ke ZHOU Ming-hua The Key Laboratory of Mountain Environment Evolution and its Regulation Institute of Mountain Hazards and Environment ResearchChinese Academy of Sciences Institute for the Study of Earth Ocean and SpaceUniversity of New Hampshire Key Laboratory of Geosciences Spatial Information Technology Ministry of Land and Resources of the ChinaChengdu University of Technology Soil and Fertilizer Research Institute Anhui Academy of Agricultural Sciences Institute for Meteorology and Climate Research Atmospheric Environmental Research (IMK-IFU)Karlsruhe Institute of Technology

Dissolved organic carbon(DOC) is an important component of the terrestrial carbon ***,the sources and controlling factors of DOC in soils remain *** this study,the effects of nitrogen(N) amendment and crop growth on DOC in soil solution were examined at a maize-wheat rotated field located in the central Sichuan Basin in southwestern *** treatments in this study included 150 kg N ha-1 season-1,200 kg N ha-1 season-1 and the control without any fertilizer *** the whole experimental period,we observed significant decreases(p<0.05) in DOC concentrations in the sampled soil solutions associated with increase in N inputs at the bare soil plots,but no change in DOC at the plots with crop *** estimated average contributions of plantderived DOC were 16%,24% and 32% of total DOC in the summer maize season and 21%,32% and 38% in the winter wheat season along with the gradient of N fertilizer application *** results implied thatthe crop growth could play a key role in the soil DOC production,and the N input enhanced DOC production by increasing crop *** relationship between the DOC concentrations and the crop root biomass was statistically significant for both the maize and winter wheat *** observations indicated that crop growth exerted greater influence on the seasonal variability of DOC concentration in soil solutions at the experimental site,which overwhelmed the effect of soil native organic matter decomposition on DOC concentrations in soil solutions.

关键词： season winter amendment maize wheat fertilizer dissolved uncertain biomass exerted

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Expression of CC Chemokine Ligand 5 in Patients with Rheumatoid Arthritis and Its Correlation with Disease Activity and Medication

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Chinese Medical Sciences Journal 2009年第1期24卷 50-54页

作者： Ming-hui Yang Feng-xia Wu Chuan-mei Xie Yu-feng Qing Guang-rong wang xiao-lan guo Zhong Tang Jing-guo Zhou guo-hua Yuan Institute of Rheumatology and Immunology Affiliated Hospital of North Sichuan Medical College Nanchong Sichuan 637000 China

Objective To determine the levels of CC chemokine ligand 5 (CCL5) in serum and synovial fluid (SF) from patients with rheumatoid arthritis (RA) and their relations with disease activity and medication. Methods CCL5 in serum and SF was quantified by enzyme-linked immunosorbent assay (ELISA) in 28 RA patients and 21 osteoarthritis (OA) patients. In RA patients, the correlations of CCL5 levels in serum and SF with disease activity were analyzed. Meanwhile, the serum CCL5 levels among RA patients treated with disease-modifying antirheumatic drugs (DMARDs), Tripterygium Glucosides, and other Chinese herbs without disease-modifying effects were also compared. Results CCL5 levels in both serum and SF of RA patients were significantly higher than those of OA patients (P<0.05). Moreover, the level of CCL5 was higher in SF than that in serum of RA patients (P<0.01). Serum CCL5 level was correlated significantly with the number of swollen joints (r=0.3329, P<0.05), erythrocyte sedimentation rate (r=0.4001, P<0.05), and C reactive protein (r=0.3735, P<0.01). In addition, the level of CCL5 had a trend of lower in patients treated with DMARDs or Tripterygium Glucosides than those treated with other Chinese herbs, although the difference was not significant among those patients due to the small number of patients in each group. Conclusions In RA patients, the expression of CCL5 increases and correlates with some clinical and laboratory parameters of RA, which indicate that CCL5 plays an important role in RA and may serve as a useful marker of disease activity. DMARDs and Tripterygium Glucosides might exert their clinical effects through reducing CCL5 production in RA.

关键词： rheumatoid arthritis chemokine CC chemokine ligand 5

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RESEARCH ON FRACTAL CHARACTERISTICS OF URBAN TRAFFIC NETWORK STRUCTURE BASED ON GIS

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Chinese Geographical Science 2002年第4期12卷 346-349页

作者： LI Jiang,wang xiao-yan,guo Qing-sh eng(School of Resources and Environment al Sciences,Wuhan University,Wuhan 430079,P.R.China) School of Resources and Environmental Sciences Wuhan University Wuhan P. R. China

Traffic network is an importance asp ect of researching controllable parameters of an urban spatial *** on GIS,traffic network str ucture complexity can be understood by using fractal geometry in which th e length-radius dimension describes change of network density,and ramification-radius dimension describes complexity and accessibility of urban *** i s propitious to analyze urban traffic network and to understand dynamic c hange process of traffic network using expanding f ractal-dimension *** the length-radius dimension and ramifica-tion-radius dimension could be rega rd as reference factor of quantitative describing urban traffic network.

关键词： urban traffic network expanding fractal dimension characteristics GIS

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Effect of Nb-V microalloying on the hot deformation behavior of medium Mn steels

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 360-368页

作者： Yumeng wang Qinyi guo Bin Hu Haiwen Luo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression *** establishing the constitutive equations for simulating the measured flow curves,we successfully constructed deformation activation energy(Q)maps and processing maps for identifying the region of flow *** concluded the following consequences of Nb-V alloying for MMS.(i)The critical strain increases and the increment diminishes with the increasing deformation temperature,suggesting that NbC precipitates more efficiently retard dynamic recrystallization(DRX)in MMS compared with solute Nb.(ii)The deformation activation energy of MMS is significantly increased and even higher than that of some reported high Mn steels,suggesting that its ability to retard DRX is greater than that of the high Mn content.(iii)The hot workability of MMS is improved by narrowing the hot processing window for the unstable flow stress,in which fine recrystallized and coarse unrecrystallized grains are present.

关键词： medium manganese steel niobium-vanadium microalloying flow behavior dynamic recrystallization hot workability

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基于DCT和KDA的人脸特征提取新方法

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电子科技大学学报 2006年第4期35卷 450-453页

作者：王孝国张雄伟解放军理工大学通信工程学院南京210007

提出了一种新的人脸特征提取方法,该方法采用DCT对人脸图像进行降维和去噪,并通过KDA提取人脸特征。基于该特征,采用NN分类器,对ORL人脸库进行分类识别,仅用28个特征平均识别率就达到97.3%,“留一法”识别率为99.5%。仿真结果表明:该方... 详细信息

提出了一种新的人脸特征提取方法,该方法采用DCT对人脸图像进行降维和去噪,并通过KDA提取人脸特征。基于该特征,采用NN分类器,对ORL人脸库进行分类识别,仅用28个特征平均识别率就达到97.3%,“留一法”识别率为99.5%。仿真结果表明:该方法有效地滤除了人脸图像中的高频干扰信息,明显增强了特征的辨别能力,同时显著地降低了特征维数和计算复杂度。

关键词：人脸识别核辨别分析最近邻分类器

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券商资产管理业务风险生成机制的实证研究

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山西财经大学学报 2006年第2期28卷 99-104页

作者：王晓国南开大学经济学院天津300061

从竞争力角度研究了券商资产管理业务的风险生成机制,结果表明,券商资产管理业务有12个风险因子,其运动变化的微观机理刻画了风险生成的路线图。实证研究发现,乘数因子是我国券商资产管理业务的主要风险因子,其生成风险的机制是垄断竞... 详细信息

从竞争力角度研究了券商资产管理业务的风险生成机制,结果表明,券商资产管理业务有12个风险因子,其运动变化的微观机理刻画了风险生成的路线图。实证研究发现,乘数因子是我国券商资产管理业务的主要风险因子,其生成风险的机制是垄断竞争市场结构,采用资金堆积做庄、博取差价的粗放投资模式,加之存在向自营业务输送利益,导致理财效率丧失、风险频发。

关键词：证券公司资产管理业务风险生成机制

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