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Changes in Soil Hot-Water Extractable C,N and P Fractions During Vegetative Restoration in Zhifanggou Watershed on the Loess Plateau

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Journal of Integrative Agriculture 2013年第12期12卷 2250-2259页

作者： UE Sha LI Peng liu guo-bin LI Zhan-bin ZHANG Chao State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau of Northwest A&F University Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry Water Resources Key Laboratory of Northwest Water Resources and Environment Ecology Ministry of Education/Xi’an University of Technology

The study was conducted in Zhifanggou Watershed,Shaanxi Province,China,to evaluate the effect of different vegetation types on hot-water extractable C,N and P fractions,with the aim to determine whether hot-water extractable fractions could be used as indicators of soil quality change in Loess *** six vegetation types established in 1975 were（i） Robinia pseudoacacia L.,（ii） Caragana korshinkii Kom.,（iii） Pinus tabulaeformis Carr.,（iv） ***-Amorpha fruticosa L.,（v） ***,and（vi） grassland.A cropped hillslope plot and a Platycladus orientalis *** forest plot were used as *** results indicated that the conversion of native forest to cropland resulted in a significant decline in the hot-water extractable C,N and P ***-water extractable C,N,and P increased when cultivated land was revegetated,but after 30 years the amount of hot-water extractable C,N,and P in revegetated fields was still much lower compared to native ***-water extractable fractions increased more under mixed-forest than under pure-forest ***,there was a significant correlation between the hot-water extractable fractions and soil chemical and microbiological *** results showed that hot-water extractable fractions could be used as indicators of soil quality change on the Loess Plateau.

关键词： soil hot-water extractable fraction vegetative restoration Loess Plateau

Effect of Different Vegetation Types on the Rhizosphere Soil Microbial Community Structure in the Loess Plateau of China

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Journal of Integrative Agriculture 2013年第11期12卷 2103-2113页

作者： ZHANG Chao liu guo-bin XUE Sha XIAO Lie State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F University Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources

The Loess Plateau in China is one of the most eroded areas in the world. Accordingly, vegetation restoration has been implemented in this area over the past two decades to remedy the soil degradation problem. Understanding the microbial community structure is essential for the sustainability of ecosystems and for the reclamation of degraded arable land. This study aimed to determine the effect of different vegetation types on microbial processes and community structure in rhizosphere soils in the Loess Plateau. The six vegetation types were as follows：two natural grassland （Artemisia capillaries and Heteropappus altaicus）, two artificial grassland （Astragalus adsurgens and Panicum virgatum）, and two artificial shrubland （Caragana korshinskii and Hippophae rhamnoides） species. The microbial community structure and functional diversity were examined by analyzing the phospholipid fatty acids （PLFAs） and community-level physiological profiles. The results showed that rhizosphere soil sampled from the H. altaicus and A. capillaries plots had the highest values of microbial biomass C, average well color development of carbon resources, Gram-negative （G-） bacterial PLFA, bacterial PLFA, total PLFA, Shannon richness, and Shannon evenness, as well as the lowest metabolic quotient. Soil sampled from the H. rhamnoides plots had the highest metabolic quotient and Gram-positive （G＋） bacterial PLFA, and soil sampled from the A. adsurgens and A. capillaries plots had the highest fungal PLFA and fungal：bacterial PLFA ratio. Correlation analysis indicated a signiifcant positive relationship among the microbial biomass C, G- bacterial PLFA, bacterial PLFA, and total PLFA. In conclusion, plant species under arid climatic conditions signiifcantly affected the microbial community structure in rhizosphere soil. Among the studied plants, natural grassland species generated the most favorable microbial conditions.

关键词： soil microbial biomass microbial community structure PLFA community-level physiological profiles,vegetation types

Soil Microbial Community Composition During Natural Recovery in the Loess Plateau, China

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Journal of Integrative Agriculture 2013年第10期12卷 1872-1883页

作者： XIAO Lie liu guo-bin XUE Sha ZHANG Chao State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F University Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resource

This study aimed to determine the characteristics of soil microbial community composition and its relationship with soil chemical properties during natural recovery in the Loess *** soil microbial community composition was analyzed by comparing the soil microbial phospholipid fatty acids（PLFAs） of eight croplands abandoned for 1,3,5,10,13,15,20,and 30 yr in the Dunshan watershed,northern Loess Plateau,*** results showed that soil organic carbon,total nitrogen,soil microbial biomass carbon,and soil microbial biomass nitrogen significantly increased with the abandonment duration,whereas the metabolic quotient significantly *** Shannon richness and Shannon evenness of PLFAs significantly increased after 10 yr of ***-negative,Gram-positive,bacterial,fungal,and total PLFAs linearly increased with increased abandonment *** analysis showed that the abandonment duration was the most important environmental factor in determining the PLFA microbial community *** soil microbial PLFAs changed from anteiso-to iso-,unsaturated to saturated,and short-to long-chain during natural ***,in the Loess Plateau,cropland abandonment for natural recovery resulted in the increase of the soil microbial PLFA biomass and microbial PLFA species and changed the microbial from chemolithotrophic to a more heterotrophic community.

关键词： abandoned cropland microbial diversity phospholipid fatty acid(PLFA) redundancy analysis(RDA) Loess Plateau

Effects of Vegetation Cover and Rainfall Intensity on Sediment-Bound Nutrient Loss,Size Composition and Volume Fractal Dimension of Sediment Particles

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Pedosphere 2011年第5期21卷 676-684页

作者： ZHANG Guan-Hua liu guo-bin WANG guo-Liang WANG Yu-Xia College of Resource and Environment Northwest A&F University Yangling 712100 (China) Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Yangling 712100 (China)

Vegetation and rainfall are two important factors affecting soil erosion and thus resulting in nutrient loss in the Chinese Loess Plateau.A field experiment was conducted to investigate the effects of rainfall intensities(60,100 and 140 mm h-1) and vegetation(Caragana korshinskii) coverages(0%,30% and 80%) on soil loss,nutrient loss,and the composition and volume fractal dimension of eroded sediment particles under simulated rainfall *** results showed that vegetation cover,rainfall intensity and their interaction all had significant effects on sediment transport and the sedimentbound nutrient *** rainfall intensity and lower coverage led to higher sediment and nutrient *** linear relationships were observed between soil loss and nutrient *** treatments showed more significant effects on the enrichment ratio(ER) of nitrogen(ERN) than organic matter(EROM) and phosphorus(ERP).Compared with the original surface soil,the eroded sediment contained more fine *** the same coverage,the clay content significantly decreased with increasing rainfall *** ER of sediment-bound nutrients was positively correlated with that of clay,suggesting that the clay fraction was preferentially eroded and soil nutrients were mainly adsorbed onto or contained within this *** were increments in the fractal dimension of the sediment particles compared to that of the original surface ***,the fractal dimension was positively correlated with clay,silt,and sediment-bound OM,N,and P contents,whereas it was negatively correlated with sand *** study demonstrated that fractal dimension analysis can be used to characterize differences in particle-size distribution and nutrient loss associated with soil erosion.

关键词： fractal features Loess Plateau particle-size distribution runoff nutrients simulated rainfall

Effects of nitrogen addition on the soil detachment in the typical grasslands of the Loess Plateau

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Journal of Mountain Science 2022年第12期19卷 3503-3516页

作者： LI Pan-pan WANG bing YANG Yan-fen liu guo-bin State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China

Nitrogen deposition will alleviate the nitrogen limitation in terrestrial ecosystems and greatly affect vegetation growth,thereby soil *** is important to clarify the effects of nitrogen addition to the plant roots and soil properties on the soil erosion process.A nitrogen addition experiment was conducted in the grassland dominated by Bothriochloa ischaemum(Linn.)Keng(BI),which has received 0,2.5,5,and 10 g N m^(-2) yr^(-1)(N_(0),N_(2.5),N_(5)and N_(10),respectively)for three consecutive ***,a total of 150 undisturbed soil samples were collected(including bare soil control)and subjected to flowing water to test their soil detachment capacities under six shear stress levels(10.2 Pa to 29.9 Pa).Three-year nitrogen addition increased the soil bulk density,soil cohesion and nitrate nitrogen while decreasing the saturated hydraulic conductivity,soil water-stable aggregates,soil organic carbon,total nitrogen and ammonium *** root mass density and root diameter decreased with nitrogen *** the root length,surface area and volume density of the N_(0) and N_(5) treatments were larger than those of the other treatments,while the plant roots were significantly inhibited by N_(10).Additionally,the soil detachment capacity(D_(c))and rill erodibility(K_(r))of the N_(0) and N_(5) treatments were significantly less than those of the N_(2.5) and N_(10)treatments,of which the Dc(0.020 kg m^(-2) s^(-1))of the N_(0) treatment was 69.0%,24.3%and 66.8%less than that of the N_(2.5),N_(5) and N_(10) treatments,*** Kr of the N_(0) treatment was 0.0012 s m^(-1),which was 72.1%,25.0%and 70.0%less than that of the *** study implies that an increase in nitrogen addition likely exacerbates soil erosion in the early(approximately 2.5 g N m^(-2) yr^(-1))and late phases(more than 10 g N m^(-2) yr^(-1)).However,when the nitrogen addition rate is approximately 5 g m^(-2) yr^(-1),soil erosion may be inhibited because of the responses of the plant ro

关键词： Nitrogen deposition Root traits Soil properties Soil detachment Grassland Loess Plateau

Research and Practice of Production Technology for High Performance Low Alloy Steels in WISCO

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Journal of Iron and Steel Research International 2011年第S1期18卷 99-103页

作者： FU Lian-chun,guo Ai-ming,liu Ji-bin,guo bin,CHEN Yan-tang [Wuhan Iron and Steel (Group) Corporation,Wuhan 430080,Hubei,China] Wuhan Iron & Steel Grp Corp Wuhan 430080 Hubei Peoples R China

The product system of high strength low alloy steels (HSLA) produced by Wuhan Iron and Steel (Group) Corporation (WISCO) was presented.A series of high performance structural steels have been developed for important construction projects around the world in different areas,such as bridge,pressure vessel,pipe line,shipbuilding,architecture,machinery and railway *** order to promote the development of large heat input welding steel,high grade thick pipeline steel and long span bridge steel,a lot of advanced production technologies have been achieved through intensive investigation,such as the control of high purity,high homogenization and free defects in steel slabs,the rules of high melting point particle formation and distribution in micro and nano scale during steel production,and the TMCP technology for ultra low carbon bainite steel for medium and heavy *** will carry on research and application of economic and weather-resistant steels and promote the developing and producing technologies of HSLA steel.

关键词： WISCO high performance low alloy steels production technology

Trueness investigation of routine creatinine assays on nine homogeneous systems in Beijing demonstrates an encouraging outcome that meets clinical requirements

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Chinese Medical Journal 2010年第17期123卷 2364-2369页

作者： liu Yan XU guo-bin Department of Clinical Laboratory Peking University First Hospital Beijing 100034 China

Background Serum creatinine （Scr） measurement plays a key role in glomerular filtration rate estimation （eGFR）,chronic kidney disease （CKD） diagnosis as well as CKD treatment. However, the test results of Scr from different laboratories vary significantly. In order to get comparable results, the European in vitro diagnostic （IVD） directive requires traceability to reference methods and materials. The purpose of this study was to verify the effect of traceability implementation by investigating the trueness of creatinine measurement on nine homogenous systems in Beijing. Methods Commutable frozen human serum reference material, National Institute of Standards ＆ Technology （NIST） Standard Reference Material （SRM） 967, was used to verify the trueness of Scr measurement results from nine homogeneous analytical systems of seven companies which are the most widely used systems in Beijing＇s third-grade hospitals. The methods referred to the Jaffe＇s and Enzymatic methods. Results from nine routine measurement systems were assessed using two criteria： biological variability and Clinical Laboratory Improvement Amendments＇ 88 （CLIA＇ 88）.We simulated a series of broken lines representing the limits of SD and bias that would produce a relative increase （or decrease） of 10% and 20% in the measurement error when estimating GFR （MEeGFR） using the isotope dilution mass spectrometry （IDMS）-traceable Modification of Diet in Renal Disease （MDRD） Study equation. Results of the College of American Pathologists （CAP） 2008-B LN24 Survey were compared with our investigation results. Results Compared with the total error criteria of biological variability, Ortho （traceable to IDMS） met the minimum acceptable criteria; Roche （Jaffe）, Roche （Enzymatic）, Shino and Daiichi met the desirable criteria at level Ⅰ. At level Ⅱ, Ortho （traceable to gas chromatography/isotope dilution mass spectrometry, GC/IDMS）, Dade Behring and Beckman （traceable to rate Jaffe） met the minimum acceptable criteria; Ro

关键词： creatinine glomerular filtration rate standardization

Direct amination of benzene to aniline with several typical vanadium complexes

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Chinese Chemical Letters 2009年第2期20卷 238-240页

作者： Yu Fen Lü Liang Fang Zhu Qiu Yuan liu bin guo Xiao Ke Hu Chang Wei Hu Key Laboratory of Green Chemistry and Technology (Sichuan University) Ministry of Education College of Chemistry Sichuan University Chengdu 610064 PR China

The liquid-phase direct catalytic amination of benzene to aniline was performed in acetic acid water solvent using a series of vanadium （Ⅲ, Ⅳ,Ⅴ） complexes with N,O- or O,O-ligands as catalysts and hydroxylamine hydrochloride as the aminating agent. The vanadium complexes exhibited much higher selectivity towards the production of aniline than NaVO3 or VOSO4. Under the optimized conditions, an aniline yield of 42.5% and a TON of 48 with a high selectivity of above 99.9% was obtained using 0.2 mmol of [VO（OAc）2] as the catalyst.

关键词： Amination Benzene Hydroxylamine Vanadium complexes

Surgical Therapeutic Strategy for Non-small Cell Lung Cancer with Mediastinal Lymph Node Metastasis (N2)

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中国肺癌杂志 2010年第4期13卷 342-348页

作者： Qianli MA Deruo liu Yongqing guo bin SHI Zhiyi SONG Yanchu TIAN Department of Thoracic Surgeryj China-Japan Friendship Hospital~ Beijing 100029 China

Background and objective Approximately 30% of patients who are diagnosed with non-small cell lung cancer (NSCLC) are classified as N2 on the basis of metastasis to the mediastinal lymph nodes. The effectiveness of surgery for these patients remains controversial. Although surgeries in recent years are proved to be effective to some extent,yet due to many reasons,5-year survival rate after surgery varies greatly from patient to patient. Thus it is necessary to select patients who have a high probability of being be cured through an operation,who are suitable to receive surgery and the best surgical methods so as to figure out the conditions under which surgical treatment can be chosen and the factors that may influence prognosis. Methods 165 out of 173 patients with N2 NSCLC were treated with surgery in our department from January 1999 to May 2003,among whom 130 were male,43 female and the sex ratio was 3:1,average age 53,ranging from 29 to 79. The database covers the patients’ complete medical history including the information of their age,sex,location and size of tumor,date of operation,surgical methods,histologic diagnosis,clinical stage,post-operative TNM stage,neoadjuvant treatment and chemoradiotherapy. The methods of clinical stage verification include chest X-ray,chest CT,PET,mediastinoscopy,bronchoscope (+?),brain CT or MRI,abdominal B ultrasound (or CT),and bone ECT. The pathological classification was based on the international standard for lung cancer (UICC 1997). Survival time was analyzed from the operation date to May 2008 with the aid of SPSS (Statistical Package for the Social Sciences) program. Kaplan-Meier survival analysis,Log-rank test and Cox multiplicity were adopted respectively to obtain patients’ survival curve,survival rate and the impact possible factors may have on their survival rate. Results The median survival time was 22 months,with 3-year survival rate reaching 28.1% and 5-year survival rate reaching 19.0%. Age,sex,different histolog

关键词：肺癌癌细胞 NSCLC 治疗