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Use of Multivariate Statistical Analysis of Hydrochemical Data for the Identification of the Geochemical Processes in the Tirana-Fushe Kuqe Alluvial Aquifer, North-Western Albania

Raço Endri, Beqiraj Arjan, Cenameri Sabina, Jahja Aurela

Journal of Ecological Engineering

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2022

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Vol. 23, nr 8

327--340

EN

During the research, 71 groundwater samples were collected over a 300 km2 area of Tirana-Fushe Kuqe alluvial aquifer extension (central-western Albania) and subsequently analyzed for 11 parameters (pH, K+, Na+, Ca2+, Mg2+, HCO3-, Cl-, SO42-, NO3-, TH and TDS). Both geochemical conventional (Piper and Chadha diagrams) methods of groundwater classification and multivariate statistical (principal components analysis – PCA and hierarchical cluster analysis – HCA) methods were applied to the dataset to evidence the geochemical processes controlling groundwater geochemistry evaluation through the aquifer. The conventional geochemical methods revealed four (G1–G4) hydrochemical groups where the dominant group is G2 the samples of which are from unconfined to semiconfined recharge zone and the majority of them have Ca-Mg-HCO3 groundwater. Group G3 includes the samples from the confined coastal aquifer having Na-Cl groundwater. Group G1 includes three groundwater samples of Ca-Mg-SO4 from the central part of the aquifer, while group G4, the samples of which are spatially located between G3 and G2 zones, has Na-HCO3 groundwater. The first four components of the PCA account for 85.35% of the total variance. Component PC1 is characterized by very high positive loadings of TH, Ca2+, and Mg2+, suggesting the importance of dissolution processes in the aquifer recharge zone. Component PC2 is characterized by very high positive loadings in Na+, K+, and Cl-and moderate to high loadings of TDS, revealing the involvement of seawater intrusion and diffusion from clay layers. On the basis of their variable loadings, the first two components are defined as the “hardness” and “salinity”, respectively. The HCA produced four geochemically distinct clusters, C1–C4. The samples of cluster C1 are from the coastal confined aquifer and their groundwater belongs to the Na-Cl type. The samples from cluster C2 are located in the south and east recharge areas and most of them have Ca–Mg–HCO3 groundwater, while the samples from cluster C3, which are located in the northeastern recharge zone, have Mg-Ca–HCO3 groundwater. Finally, cluster C4 includes two groundwater subgroups having Na-Cl-HCO3 and Na-Mg-Cl-HCO3 groundwater in the vicinity of cluster C1 as well as Na-HCO3-Cl and Na-Mg-HCO3-Cl groundwater next to cluster C2 and C3.

2

Application of Multivariate Statistical Methods to the Hydrochemical Study of Groundwater Quality in the Sahel Watershed, Algeria

Hakim Djafer Khodja, Amina Aichour, Amina Rezig, Djouhra Baloul, Ahmed Ferhati

Journal of Ecological Engineering

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2022

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Vol. 23, nr 8

341--349

EN

The quality of groundwater is characterized by several numbers of physical and chemical parameters, which determine the use of water (water supply, irrigation, industry). This search paper is a contribution made to know the hydrochemical characteristics of groundwater in the Sahel sub-catchment which belongs to the large Soummam North basin of Algeria. Different multivariate statistical techniques were used such as principal component analysis (PCA), Hierarchical Cluster Analysis (HCA) and Diagram Analysis. These analyses are exercised to a dataset formed from 37 boreholes with 12 chemical variables over the entire surface of the watershed. The samples were collected in 2016. The 37 boreholes are one of the main water resources that supply the wilaya of Bouira with drinking water and irrigation. The analysis of water quality using different methods (ACP, HCA and Diagram) resulted in two chemical kinds: (Chloride, calcium sulfate and magnesium), and (Bicarbonate calcium and magnesium). The results have shown that 74% of the boreholes were contaminated, the rest of boreholes were characterized by a good quality and they have not suffered any contamination and can be consumed without any risk.

3

Clustering of some Liquidambar orientalis samples according to essential oil compositions

Akpolat O., Kaplaner E., Duru M. E.

Elektronika : konstrukcje, technologie, zastosowania

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2018

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Vol. 59, nr 10

27--30

EN

Liquidambar orientalis have been used widely for traditional medicine in Anatolia, especially for wounding injuries. Chemical composition of 17 essential oil of Liquidambar orientalis leaves from different locations were studied using GC-FID. Similarity and the differences of the samples were determined depending on major component contents using Hierarchical Cluster Analysis (HCA) by MATLAB. 11 major essential oil in the samples were identified namely; α-Pinene, β-pinene, thujone-α, terpinolene, α-terpinene, γ-terpinene, 2-carene, terpinen-4-ol, α-terpineol, β-caryophyllene and germacrene-D, respectively. Locations and seasonal changes discriminated the Liquidambar orientalis samples from each other.

PL

Liquidambar orientalis były szeroko stosowane w medycynie tradycyjnej w Anatolii, szczególnie w przypadku ran zranienia. Skład chemiczny 17 olejków eterycznych z liści Liquidambar orientalis z różnych lokalizacji zbadano za pomocą GC-FID. Podobieństwo i różnice w próbkach określano w zależności od głównych składników przy użyciu Hierarchical Cluster Analysis (HCA) firmy MATLAB. Zidentyfikowano 11 głównych olejków eterycznych w próbkach, mianowicie; α-Pinen, β-pinen, tujone-α, terpinolen, α-terpinen, γ-terpinen, 2-carene, terpinen-4-ol, α-terpineol, β-kariofylen i germacren-D, odpowiednio. Lokalizacje i zmiany sezonowe odróżniały próbki Liquidambar orientalis od siebie nawzajem.

4

An identification source of variation on the water quality pattern in the Malacca River basin using chemometric approach

Hua A. K.

Archives of Environmental Protection

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2018

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Vol. 44, no. 4

111--122

EN

The Malacca River basin experienced river water pollution which caused a major deterioration to the ecosystems and environmental health. This study is carried out to assess the water quality data and identify the pattern of water pollution sources in the study area, and also to develop a predictive performance of water quality in the Malacca River basin. A chemometric approach using a combination of HCA, DA, PCA, and MLR, was applied into twenty water quality variables from nine sampling stations that were collected from January until December of 2015 in the river basin. HCA pointed out three clusters, namely Cluster 1 (C1) with low pollution source, Cluster 2 (C2) with moderate pollution source, and Cluster 3 (C3) with high pollution source. In the DA analysis, the results showed 21 variables, 12 variables, and 9 variables for standard mode, forward stepwise mode, and backward stepwise mode, respectively. Meanwhile, the PCA indicated that the main source of pollutants is detected from residential, industrial, commercial, agricultural, animal livestock, as well as forest land. Among the three models developed from MLR analysis, C3 with a high pollution source is detected to be the most suitable model to be used for the prediction of Water Quality Index in the Malacca River basin. This study proposed for an effective river water quality management by having new water quality monitoring network to be designed for more practical use in order to reduce time and effort, as well as cost saving purposes.

5

Multiple compounds determination and fingerprint analysis of Agrimonia pilosa Ledeb by high-performance liquid chromatography

Wang Y., Yin L., Lv G., Xu Y., Xu L., Qi Y., Zheng L., Peng J.

Acta Chromatographica

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2014

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Vol. 26, no. 1

137--156

EN

In the present paper, a simple and reliable high-performance liquid chromatography-diode array detection (HPLC-DAD) method was developed both for quantitative determination and fingerprint analysis of Agrimonia pilosa Ledeb for quality control. Under the optimized HPLC conditions, seven bioactive compounds including rutin, quercetin-3-rhamnoside, luteoloside, tiliroside, apigenin, kaempferol, and agrimonolide were determined simultaneously. For fingerprint analysis, 11 common peaks were selected as the characteristic peaks to evaluate the similarities of 16 different samples collected from different origins in China. Besides, hierarchical cluster analysis (HCA) was also performed to evaluate the variation of the raw materials. This is the first report of using a simple method for quality control of A. pilosa Ledeb through multi-component determination and chromatographic fingerprint analysis to the best of our knowledge.

6

Semi-automatic watershed merging method

Smołka J., Skublewska-Paszkowska M.

Annales Universitatis Mariae Curie-Skłodowska. Sectio AI, Informatica

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2013

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Vol. 13, no. 1

89--97

EN

Watershed transformation frequently produces over-segmented images. The authors propose a solution to this problem. It utilizes hierarchical cluster analysis for grouping watersheds which are treated as objects characterized by a number of attributes. Initially the watershed merging method was meant only for gray-scale images, but later it was adapted for colour images. This paper presents further extension of the method that allows it to either automatically select the numberof classes or to provide a hint as to which numbers in a specified range should be considered first.Segmentation quality assessment functions for colour images are presented. The results obtained using an extended watershed merging method are discussed. The examples of segmentations selected by the method, along with the graphs of assessment functions, are shown.

7

Study of retention of 31 polyoxygenated steroids by normal- and reversed-phase thin-layer chromatography

Tosti T, Natić M, Smoliński A., Milić D, Milojković-Opsenica D, Tešić Ž

Acta Chromatographica

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2011

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Vol. 23, no. 3

429--445

EN

The chromatographic behavior of 31 steroidal compounds on both silica gel and RP-18 silica thin layers using nonaqueous and aqueous-organic mobile phases was investigated. It was found that an application of more polar solvent systems such as acetonitrile-dichloromethane in comparison to acetone-n-hexane resulted in stronger elution of the investigated substances in all investigated cases. Under normal-phase conditions better selectivity was achieved in acetonitrile-dichloromethane and the best in binary mixture with component ratio 1:9 (υ/υ). The selectivity of the separation under reversed-phase conditions was increased with the increased fraction of water in mobile phases used. A conclusion on the influence of substance moiety on the retention behavior of the investigated substances under reversed-phase conditions could not be drawn due to complex retention mechanism. In order to find similarities and dissimilarities between normal- and reversed-phase systems used, retention parameters were investigated by principal component analysis and cluster analysis.

8

Intuitionistic fuzzy sets clustering (IFSC) with an application in psychology

Pasha E., Fatemi A.

Journal of Mathematics and Applications

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2006

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Vol. 28

113-120

EN

In this paper we present a new method for clustering when the sets are IFS.To reach this goal we use distance content in IFSs and hierarchical clustering methods.