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Response of Stream Pollution Characteristics to Catchment Land Cover in Cao-E River Basin, China

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Pedosphere 2011年第1期21卷 115-123页

作者： SHEN Ye-Na LUE Jun CHEN Ding-Jiang SHI Yi-Ming Department of Natural Resources College of Environmental Science and Natural Resources Zhejiang University Hangzhou 310029 (China) China Ministry of Education Key Lab of Environmental Remediation and Ecological Health Zhejiang University Hangzhou 310029 (China) Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition Zhejiang University Hangzhou 310029 (China)

This study addressed the relationship of river water pollution characteristics to land covers and human activities in the catchments in a complete river system named Cao-E River in eastern *** on the hydrogeochemical data collected monthly over a period of 3 years,cluster analysis(CA) and principal component analysis(PCA) were adopted to categorize the river reaches and reveal their pollution *** to the differences of water quality in the river reaches and land use patterns and average population densities in their catchments,the whole river system could be categorized into three groups of river reaches,i.e.,non-point sources pollution reaches(NPSPR),urban reaches(UR) and mixed sources pollution reaches(MSPR).In UR and MSPR,the water quality was mainly impacted by nutrient and organic pollution,while in NPSPR nutrient pollution was the main *** nitrate was the main nitrogen form in NPSPR and particulate phosphorus was the main phosphorus form in *** were no apparent trends for the variations of pollutant concentrations with increasing river flows in NPSPR and MSPR,while in UR the pollutant concentrations decreased with increasing river *** dry season was the critical period for water pollution control in ***,catchment land covers and human activities had significant impact on river reach water pollution type,nutrient forms and water quality responses to hydrological conditions,which might be crucial for developing strategies to combat water pollution in watershed scale.

关键词： cluster analysis hydrological conditions pollution factors principle component analysis water quality

MOLECULAR POLARIZATION INDUCTION IN CONCERTED MECHANISM OF ALKOXY MIGRATION

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Chinese Chemical Letters 1991年第12期2卷 933-934页

作者： Guo Qiang CHEN Biochemistry Section, Basic Department, Zhejiang AgricuLturat University, Hangzhou 310029

The rearrangement of α-substituted phenyl-α, α′-dimethoxypropanones (R1) was recently proved to he an [1, 3] siqmatropic migration of methoxy group by study of LFER, solvent effect, crossover experiment, and by other means. The rearrangement catalysed by trace of totuenesulfonic acid gave a negligible value of the Hammett reaction constant. Further experimental results show that the electronic effect of substituent on the aromatic ring for the rearrangement in neutral medium is much greater (Table 1). We propose sigmatropic migration

关键词： Chen MOLECULAR POLARIZATION INDUCTION IN CONCERTED MECHANISM OF ALKOXY MIGRATION

Pollution　monitoring　of　marine　organisms　grown　in　the　Zhoushan　Sea　of　China

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Journal of Environmental Sciences 1997年第3期9卷 35-39页

作者： Zhou Qixing, Zhu Yinmei Department of Environmental Sciences, Zhejiang Agricultural University, Hangzhou 310029, China

The sustainable regeneration of the biggest fishery resource in the Zhoushan Sea area of China has been adversely affected in recent years. Wastewater discharged into the marine ecosystem is the main source of pollution. Affected organisms such as hairtail prawn, jellyfish, crab, laver and kelp were monitored, and the contributions and fluxes of three sort of pollutants(oils, Cr and phenol) from the expansion of rural enterprises in the Yangtze River valley, the Qiantang River valley, the Ningbo coastal area and the Zhoushan islands were calculated. More than 16 chemical pollutants were jointly responsible for the decrease in the yield and quality of marine organisms. Furthermore, combined contamination effects and their joint toxicity differed between summer and winter, because they were varied with different temperature, salinity, pH and E h.

关键词： pollution monitoring marine environment affected organism.

Modified accumulation of selected heavy metals in Bt transgenic rice

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Journal of Environmental Sciences 2009年第11期21卷 1607-1612页

作者： WANG Haiyan, HUANG Jianzhong, YE Qingfu, WU Dianxing, CHEN Ziyuan Institute of Nuclear Agricultural Sciences, Key Laboratory of Nuclear Agricultural Sciences of Ministry of Agriculture and Zhejiang Province, Zhejiang University, Hangzhou 310029, China Institute of Nuclear Agricultural Sciences Key Laboratory of Nuclear Agricultural Sciences of Ministry of Agriculture and Zhejiang Province Zhejiang University Hangzhou 310029 China

Safety assessment of genetically modified crops generally does not take into account the potential hazard of altered patterns of heavy metal accumulation in plants. A pot experiment was conducted under greenhouse conditions to evaluate the impact of heavy metal amendments on the accumulation of Cd, Cu, Pb and Zn in a Bt transgenic rice Ke-Ming-Dao （KMD） and its wild-type Xiushui 11 （Xs11）. In control soils, significant difference was only found in contents of Cu （p 〈 0.01） and Pb （p 〈 0.05） in straw between KMD and Xs11. At three levels of Cd amendments （5, 10, and 20 mg/kg）, the Cd contents in grain and straw of KMD were significantly higher than those of Xs11, and all grain Cd contents were significantly higher than the International Criteria （0.2-0.4 mg/kg） as specified by the Codex Alimentarius Commission （CAC）. These results implied that it may be unsafe for growing Bt transgenic rice in heavily Cd-polluted areas. No significant difference in Zn was found between the two varieties with the exception of roots at Zn amendment level of 600 mg/kg, while Pb contents in KMD were much higher in the straw at the lead amendment level of 1000 mg/kg and in the root at 250 mg Pb/kg. Data on the heavy metal accumulation patterns for the genetically modified rice may be used for the selection of growing areas as well as for plant residue management for Bt rice.

关键词： Bt transgenic rice heavy metal bioaccumulation trace elements

Synthesis of Reassortant Infectious Bursal Disease Virus in Chickens Injected Directly with Infectious Clones from Different Virus Strains

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Acta Biochimica et Biophysica Sinica 2005年第3期37卷 192-198页

作者： Long LI Yao-Wei HUANG Lian-Sheng WANG Wang-Jun WAN Lian YU Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine,Institute of Preventive Veterinary Medicine.Zhejiang University.Hangzhou 310029,China Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine Institute of Preventive Veterinary Medicine Zhejiang UniversityHangzhou 310029 China

The infectious bursal disease virus（IBDV）,a member of the Birnaviridae family,containinga bisegmented double-stranded RNA genome,encodes four structural viral proteins,VP1,VP2,VP3,andVP4,as well as a non-structural protein,VP5,In the present paper,the segment A from two IBDV strains,field isolate ZJ2000 and attenuated strain HZ2,were inserted into one NaeI site by site-directed silent mu-tagenesis and subcloned into the eukaryotic expression plasmid pCI under the control of the human cy-tomegalovirus（hCMV）immediate early enhancer and promoter to construct the recombinant plasmids pCI-AKZJ2000and pCI-AKHZ2,*** of the two recombinants was combined with another recombinant pCIplasroid containing the marked segment B of strain HZ2（pCI-mB）,and injected intramuscularly into non-immunized *** chimeric IBDV strains were recovered from the *** out of eightchickens in each of two groups showed the bursal histopathological *** reassortant virus derivedfrom pCI-AKZJ2000/pCI-mB can infect chicken embryos and shows relatively low *** havedeveloped a novel virus reverse genetic approach for the study of *** results also form the basis forinvestigating the role of VP1 in viral replication and pathogenecity.

关键词： infectious bursal disease infectious bursal disease virus reverse genetics reassortant virus animal model

Empirical Line Method Using Spectrally Stable Targets to Calibrate IKONOS Imagery

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Pedosphere 2008年第1期18卷 124-130页

作者： XU Jun-Feng Institute of Agricultural Remote Sensing and Information Technology Zhejiang University Hangzhou 310029 （China）.

By using speetrally stable targets, the empirical line （EL） method was tested to correct the multispectral IKONOS imagery acquired over Putuo Mountain, Zhejiang, China. A series of calibration targets, which were spectrally stable over time, were selected to establish the linear predicted equation. Subsequently, a series of spectrally stable validation targets were selected to assess the accuracy of the equations. And, validation targets, which were speetrally unstable over time, were used to test the feasibility of using the EL method to calibrate the archival remotely sensed data. Ground reflectance measurements for each target were made using an ASD FieldSpec spectroradiometer. A Trimble GeoXTTM GPS unit with sub-meter accuracy was used to estimate the target position accurately. Linear regression equations for four tKONOS bands were derived. The coefficients of determination for the blue, green, and red bands were all greater than 0.9800 and it was 0.9697 for the near infrared band. It was concluded that reasonable results could be obtained by using speetrally stable targets.

关键词： calibration empirical line method, IKONOS spectrally stable targets

Genotypic Differences of Forage Crop Tolerance to Acid Soils

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Pedosphere 1998年第4期8卷 337-342页

作者： YANG YUAI CHU XIANGYUN YANG XIAOE WANG KE and HE ZHENLI (Department of Soil Science and Agricultural Chemistry, Zhejiang Agricultural University, Hangzhou 310029China) Department of Soil Science and Agricultural Chemistry Zhejiang Agricultural University Hangzhou 310029 China

Twenty eight species of forage crops were planted on acid soils derived from Quaternary red clay (pH 4.16)and red sandstone (pH 4.55) to study genotypic differences of the forage crops in tolerance to acid soils as affected by liming, phosporus and potassium fertilizer application. Eight forage species, Lolium multiflorum L., Brachiaria decumbens, Digitaria sumtisii, Melinis minutiflora, Paspalum dilatatum, Paspalum wettsteinii,Sataria viridis Beanv and Shcep’s Festuca, were highly tolerant to acid soils, and grew relatively well in the tested soils without lime application, whereas most of the other 20 tested forage species such as Lolium perenne L., Meadow Festuca and Trifolium pratense L. were intolerant to acid soils, showing retarded growth when the soil pH was below 5.5 and significant increase in dry matter yields by phosphrus fertilizer application at soil pH 6.0. Results showed that large differences in tolerance to acid soils existed among the forage species,and tolerance of the forage species to acid soils might be closely associated with their tolerance to Al and P efficiency.

关键词： acid soil forage crop species phosphorus fertilizer potassium fertilizer

Heavy Metals, Phosphorus and Some Other Elements in Urban Soils of Hangzhou City, China

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Pedosphere 2004年第2期14卷 177-185页

作者： ZHANGMing-Kui KEZi-Xia DepartmentofNaturalResourceScience CollegeofNaturalResourceandEnvironmentalSciencesZhefiangUniversityHangzhou310029（China）.E-mail：mkzhang@***

Health implications of inhaling and/or ingesting dust particles with high concentrations of heavy metals from urban soils are a subject of intense concern. Understanding the geochemistry of these metals is key to their effective management. Total concentrations of heavy metals,phosphorus (P) and 8 other elements from topsoil samples collected at 82 locations in Hangzhou City were measured to:a) assess their distribution in urban environments; and b) understand their differentiation as related to land use. Metal mobility was also studied using a three-step sequential chemical fractionation procedure. About 8.5%,1.2%,3.6%,11.0% and 30.3% of the soil samples had Cd,Cr,Cu,Pb,and Zn concentrations,respectively,above their allowable limits for public and private green areas and residential use. However,in commercial and industrial areas,most samples had metal concentrations below their allowable limits. Statistical analyses revealed that the 16 measured elements in urban soils could be divided into four groups based on natural or anthropic sources using a hierarchical cluster analysis. Additionally,Cu,Pb,and P showed similar spatial distributions with significant pollution in commercial zones,suggesting vehicle traffic or commercial activities as dominant pollutant sources. Also,Cd,Co,Cr,Ni,Zn,Mn and Fe had the highest concentrations in industrial locations,signifying that industrial activities were the main sources of these seven metals. Moreover,the data highlighted land-use as a major influence on heavy metal concentrations and forms found in topsoils with large proportions of soil Cd,Co,Cr,and Ni found in residual fractions and soil Cu,Pb and Zn mainly as extractable fractions.

关键词： anthropogenic pollution heavy metals phosphorus urban soils

Adsorption of Metsulfuron and Bensulfuron on a Cationic Surfactant-Modified Paddy Soil

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Pedosphere 2007年第1期17卷 101-108页

作者： LIAO Min XIE Xiao-Mei College of Environmental and Resource Sciences Department of Resources Science Zhejiang University Hangzhou 310029 （China）

Adsorption isotherms of metsulfuron and bensulfuron on a hexadecyltrimethylammonium （HDTMA） bromide-modified paddy soil under different ionic strengths, with divalent cation Cu^2＋, or having different pH were studied to describe their adsorptive behavior, and to try to explain the adsorption process of a sulfonylurea compound with a carbamoylsulfamoyl group in the modified soil environment. All the adsorption isotherms fitted the Freundlich equation well, and the HDTMA treatment of paddy soil dramatically enhanced adsorption capacity of metsulfuron or bensulfuron. Also, an increase of ionic strength and the addition of divalent heavy metal cation Cu^2＋ on the HDTMA-modified paddy soil increased the adsorption of metsulfuron or bensulfuron. Additionally, for metsulfuron and bensulfuron in the aqueous phase, adsorption capacity of the HDTMA-modified paddy soft gradually increased with decreasing pH.

关键词： adsorption bensulfuron cationic surfactant metsulfuron paddy soil