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Application of multivariate statistical techniques in assessment of surface water quality in Second Songhua River basin,China

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Journal of Central South University 2016年第5期23卷 1040-1051页

作者：郑力燕于宏兵王启山 College of Environmental Science and Engineering Nankai University

multivariate statistical techniques,such as cluster analysis(CA),discriminant analysis(DA),principal component analysis(PCA) and factor analysis(FA),were applied to evaluate and interpret the surface water quality data sets of the Second Songhua River(SSHR) basin in China,obtained during two years(2012-2013) of monitoring of 10 physicochemical parameters at 15 different *** results showed that most of physicochemical parameters varied significantly among the sampling *** significant groups,highly polluted(HP),moderately polluted(MP) and less polluted(LP),of sampling sites were obtained through Hierarchical agglomerative CA on the basis of similarity of water quality *** identified p H,F,DO,NH3-N,COD and VPhs were the most important parameters contributing to spatial variations of surface water ***,DA did not give a considerable data reduction(40% reduction).PCA/FA resulted in three,three and four latent factors explaining 70%,62% and 71% of the total variance in water quality data sets of HP,MP and LP regions,*** revealed that the SSHR water chemistry was strongly affected by anthropogenic activities(point sources:industrial effluents and wastewater treatment plants;non-point sources:domestic sewage,livestock operations and agricultural activities) and natural processes(seasonal effect,and natural inputs).PCA/FA in the whole basin showed the best results for data reduction because it used only two parameters(about 80% reduction) as the most important parameters to explain 72% of the data ***,this work illustrated the utility of multivariate statistical techniques for analysis and interpretation of datasets and,in water quality assessment,identification of pollution sources/factors and understanding spatial variations in water quality for effective stream water quality management.

关键词： Second Songhua River basin water quality multivariate statistical techniques cluster analysis discriminant analysis principal component analysis factor analysis

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Chemical comparison of Semen Euphorbiae and Semen Euphorbiae Pulveratum by UPLC-Q-TOF/MS coupled with multivariate statistical techniques

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Journal of Chinese Pharmaceutical Sciences 2020年第7期29卷 470-479页

作者： Huinan Wang Jingzhen Zhang Yuexin Cui Siyu Wang Hui Gao Yao Zhang Xinjie Wang Ziye Yang Mengyu Chen Peihua Wang Guimei Zhang Yingzi Wang Chao Zhang School of Chinese Materia Medica Beijing University of Chinese MedicineBeijing102488China School of Pharmaceutical Sciences Shandong University of Traditional Chinese MedicineJinan 250355China

In the present study,we aimed to assess the chemical composition changes of Semen Euphorbiae(SE)and Semen Euphorbiae Pulveratum(SEP)by UPLC-Q-TOF/MS and multivariate statistical *** UPLC-Q-TOF/MS method and SIMCA-P software were used to analyze the changes of chemical components of SE and SEP based on PCA and PLS-DA multivariate statistical methods.A"component-target-disease"network model was constructed by Intelligent Platform for Life Sciences of traditional Chinese medicine(TCM)to predict potential related *** differences of chemical composition were significant between SE and *** positive ion mode,the amounts of Euphorbia factor L2,L3,L7a,L8,L9 and lathyrol were obviously decreased after *** negative ion mode,the amounts of aesculetin,bisaesculetin,ingenol and cetylic acid were increased obviously,while Euphorbia factor L1,L4 and L5 were decreased obviously after processing,and the components of euphobiasteroid,aesculetin,lathyrol and linoleic acid among the 14 differentiated compounds were closely related to the SE-related diseases through the"component-target-disease"network ***-Q-TOF/MS technology in combination with multivariate statistical methods had certain advantages in studying the complex changes of chemical composition before and after manufacturing pulveratum of *** provided a basis for clarifying the toxicity-attenuated mechanisms of SE manufacturing pulveratum,and laid the foundation for its further development and utilization.

关键词： Semen Euphorbiae Semen Euphorbiae Pulveratum UPLC-Q-TOF/MS multivariate statistical techniques Chemical constituents Manufacturing pulveratum

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Temporal and spatial variations hydrochemical components and driving factors in Baiyangdian Lake in the Northern Plain of China

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Journal of Groundwater Science and Engineering 2024年第3期12卷 293-308页

作者： Tian-lun Zhai Qian-qian Zhang Long Wang Hui-wei Wang Hebei and China Geological Survey Key Laboratory of Groundwater Remediation Institute of Hydrogeology and Environmental GeologyChinese Academy of Geological SciencesShijiazhuang 050061China

Understanding the temporal and spatial variation of hydrochemical components in large freshwater lakes is crucial for effective management and *** this study,we identify the temporalspatial characteristics and driving factors of the hydrochemical components in Baiyangdian Lake using geochemical methods(Gibbs diagram,Piper diagram and End-element diagram of ion ratio)and multivariate statistical techniques(Principal component analysis and Correlation analysis).16 sets of samples were collected from Baiyangdian Lake in May(normal season),July(flood season),and December(dry season)of *** indicate significant spatial variation in Nat,ci,SO and NO,,suggesting a strong influence of human *** concentrations exhibit greater seasonal variation in the dry season compared to the flood season,while the concentrations of the four anions show inconsistent seasonal changes due to the combined effects of river water chemical composition and human *** hydrochemical type of Baiyangdian Lake is primarily HCO,***,Mg*and HCO,originate mainly from silicate and carbonate rock dissolution,while Kt,Nat and CI originate mainly from sewage and salt dissolution in ***42 may mainly stem from industrial wastewater,while NO,primarily originates from animal feces and domestic *** the use of Principal Component Analysis,it is identified that water-rock interaction(silicate and carbonate rocks dissolution,and dissolution of salt in sediments),carbonate sedimentation,sewage,agricultural fertilizer and manure,and nitrification are the main driving factors of the variation of hydrochemical components of Baiyangdian Lake across three hydrological *** findings suggest the need for effective control of substandard domestic sewage discharge,optimization of agricultural fertilization strategies,and proper management of animal manure to comprehensively improve the water environment in Baiyangdian Lake.

关键词： Hydrochemical variation Sources Human activities Water-rock interaction multivariate statistical techniques

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multivariate analysis of surface water quality in the Three Gorges area of China and implications for water management

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Journal of Environmental Sciences 2011年第9期23卷 1460-1471页

作者： Jian Zhao Guo Fu Kun Lei Yanwu Li Chinese Research Academy of Environmental Sciences Beijing 100012 China.

multivariate statistical techniques,cluster analysis,non-parametric tests,and factor analysis were applied to analyze a water quality dataset including 13 parameters at 37 sites of the Three Gorges area,China,from 2003–2008 to investigate spatio-temporal variations and identify potential pollution *** cluster analysis,the twelve months of the year were classified into three periods of lowflow （LF）,normal-flow （NF）,and high-flow （HF）;and the 37 monitoring sites were divided into low pollution （LP）,moderate pollution （MP）,and high pollution （HP）.Dissolved oxygen （DO）,potassium permanganate index （COD Mn ）,and ammonia-nitrogen （NH 4 ＋-N） were identified as significant variables affecting temporal and spatial variations by non-parametric *** analysis identified that the major pollutants in the HP region were organic matters and nutrients during NF,heavy metals during LF,and petroleum during *** the MP region,the identified pollutants primarily included organic matter and heavy metals year-around,while in the LP region,organic pollution was significant during both NF and HF,and nutrient and heavy metal levels were high during both LF and *** main sources of pollution came from domestic wastewater and agricultural activities and runoff;however,they contributed differently to each region in regards to pollution *** the HP region,inputs from wastewater treatment plants were significant;but for MP and LP regions,water pollution was more likely from the combined effects of agriculture,domestic wastewater,and chemical *** results provide fundamental information for developing better water pollution control strategies for the Three Gorges area.

关键词： water quality spatial variations seasonal variations multivariate statistical techniques the Three Gorges

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The role of graveyards in species conservation and beta diversity:a vegetation appraisal of sacred habitats from Bannu,Pakistan

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Journal of Forestry Research 2020年第4期31卷 1147-1158页

作者： Saqib Kamran Shujaul Mulk Khan Zeeshan Ahmad Amjad Ur Rahman Majid Iqbal Fazal Manan Zahoor Ul Haq Saif Ullah Department of Plant Sciences Quaid-i-Azam UniversityIslamabadPakistan

Graveyards or sacred groves are often places of natural vegetation protected by spiritual believers because of their sacred beliefs and indigenous culture.A study of graveyards was conducted to determine their role in species conservation,community formation,and associated indicators and species composition using multivariate statistical *** was hypothesized that variations in the age of graveyards would give rise to diverse plant communities under the impact of various edaphic and climatic *** ecological techniques were applied to determine various phytosociological *** the data were put in MS Excel for analysis in PCORD and CANOCO softwares for cluster analysis(CA),two-way cluster analysis(TWCA),indicator species analysis and canonical correspondence *** and TWCA through Sorenson distance measurements identified five major graveyard plant communities:(1)FicusBougainvillea-Chenopodium;(2)Acacia-Datura-Convolvulus;(3)Ziziphus-Vitex-Abutilon;(4)Acacia-Lantana-Salsola;and(5)*** such as Capparis decidua,Herniaria hirsuta,Salvadora oliedes and Populus euphratica were only present inside graveyards rather than outside and advocate the role of graveyards in species *** impact of different environmental and climatic variables plus the age of the graveyards were also assessed for comparison of plant communities and their respective indicator *** results indicate that higher chlorine concentration,age of graveyards,low soil electrical conductivity,lower anthropogenic activities,higher nitrogen,calcium and magnesium concentrations in the soil,and sandy soils were the strong environmental variables playing a significant role in the formation of graveyard plant communities,their associated indicators and species distribution *** results could further be utilized to evaluate the role of edaphic and climatic factors,indicator species and conservation management practices at a gr

关键词： Graveyards/Sacred groves Plant communities multivariate statistical techniques Indicator species Edaphic factors Conservation PCORD software

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Multicriteria to estimate the environmental risk of sediment from the Obedska Bog(Northern Serbia),a reservation area on UNESCO's list

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International Journal of Sediment Research 2020年第5期35卷 527-539页

作者： Dejan Kr?mar Nenad Grba Marijana Kragulj Isakovski Nata?a Varga Jelena Spasojevi? Jasmina Agbaba Bozo Du?an Dalmacija University of Novi Sad Faculty of Sciences Department of ChemistryBiochemistry and Environmental Protection

The objective of this current study is to compare related sediment legislation standards and norms to the diversity and influence of anthropogenic and natural(geogenic) sources of pollution in the investigated fluvial relief test site region of the Obedska *** metals(nickel(Ni).zinc(Zn),cadmium(Cd),copper(Cu) and lead(Pb) except chromium(Cr)) and arsenic(As) have higher values than the Upper Continental Crust(UCC) for loess *** sharp leaps in the enrichment factor(r) suggested "indicators of anthropogenic metal pollution" for Cd,Cu(r> 5.0) and Zn,Ni(r> 1.0) for this *** addition,the Chemical Proxy of Alteration(CPA,60-95) from the unique Jadar block terrane and neighbouring representative catchment areas,confirmed moderate to higher intensity of *** Component Analysis/Factor Analysis(PCA/FA) and cluster analysis suggest that Ni,Zn,Cu and Cd are derived from several anthropogenic sources,whereas As is convincingly of geogenic origin,and Pb and Cr exhibit dual *** sum of 16 *** Protection Agency Polycyclic Aromatic Hydrocarbons(EPA PAHs) indicated heterogenic sources,but minor effects to *** results of the current investigation indicated intensive and highly diffuse sources of pollution in this United Nations Educational,Scientific and Cultural Organization [UNESCO's] *** outcomes indicate that Cu should be added to the European Union [EU] watch list of emerging contaminants.

关键词： Priority substances in sediment Contamination criteria multivariate statistical techniques Heterogeneous sources

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