scholarly journals Hydro-chemical and microbiological characterization of Lower Cretaceous waters in a semi-arid zone Beni-Ounif syncline, South-West of Algeria

2019 ◽  
Vol 40 (1) ◽  
pp. 67-80
Author(s):  
Fatima Zahra Merzougui ◽  
Ahmed Makhloufi ◽  
Touhami Merzougui

Abstract The article analyses the water quality of the Lower Cretaceous aquifer in the Beni-Ounif syncline. To this end, 42 samples were taken for physico-chemical analysis and 28 for microbiological analysis in March, May and October 2017 from 14 sampling points. The results of physico-chemical analysis were processed by multi-variety statistical analysis methods: principal component analysis (PCA) and hierarchical cluster analysis (HCA) coupled to hydro chemical methods: Piper diagram. The PCA allowed us to explore the connections between physico-chemical parameters and similarities between samples and to identify the most appropriate physico-chemical elements to describe water quality. The HCA allowed us to classify the sampling points according to the similarity between them and thus reduce them for the next follow-up analysis. Waters of the syncline are characterized by medium to low mineralization (320 < EC < 7600 μS∙cm–1 and 200 < RS < 4020 mg∙dm−3) and hardness of between 22 and 123°f. Only 19% of the samples show NO3 concentrations exceeding the Algerian standards. Microbiologically, the study reports the presence of bacteria: coliforms (<8 CFU∙0.1 dm−3), Streptococcus D (<1100 CFUꞏ0.1 dm–3), Clostridium sulphito-reducer of vegetative form (<90 CFUꞏ0.02 dm–3) and sporulate (<4 CFUꞏ0.02 dm–3), total aerobic mesophilic flora at 22°C (<462 CFUꞏ0.001 dm–3) and at 37°C (<403 CFUꞏ0.001 dm–3). It must be noted that no presence of thermo-tolerant coliforms is observed.

Author(s):  
Andressa Beló ◽  
Alvaro Luiz Mathias ◽  
Carlos Alberto Ubirajara Gontarski

The cyanobacterial bloom is a consequence of eutrophication in a lentic environment. It is attributed to the contribution of nutrients related to anthropic action, as well as geographic and physico-chemical conditions. Water quality parameters of Alagados reservoir, which supplies Ponta Grossa, were determined between 08/2013 and 08/2014 to evaluate their effects on the occurrence of bloom. Some parameters, such as pH (9.1), DO (4.2 mg L-1), BOD (39 mg L-1), TP (0.86 mg L-1) and number of cyanobacterial cells (372,536 cells mL-1), were outside the limits recommended by CONAMA 357/05 for Class II and Decree 2,914/11 of the Ministry of Health. The bloom was predominantly caused by the overdevelopment of Cylindrospermopsis sp. and required additional use of chemical products in the treatment of municipal water supplies, to include coagulant (19.6%), polymer (21.0%) and activated carbon (1,889%), with a corresponding cost increase of 58%. The Water Quality Index confirmed the worsening of reservoir water quality during bloom. The Principal Component Analysis of historical data (01/2003 to 08/2014) did not discriminate the cyanobacteria levels classes (< 2,000, 2,000-20,000, 20,000-50,000 and > 50,000 cells mL-1) based on Brazilian standards, which was confirmed by the Hierarchical Cluster Analysis; although it confirmed a logical correlation between some parameters (climatic condition-reservoir rainfall-reservoir level and BOD-COD). The unidentified correlations can be attributed to the adaptability of Cylindrospermopsis sp. and the ecological complexity that requires higher sampling frequency.


2016 ◽  
Vol 75 (6) ◽  
pp. 1319-1331 ◽  
Author(s):  
M. E. Monapathi ◽  
C. C. Bezuidenhout ◽  
O. H. J. Rhode

Yeasts from water sources have been associated with diseases ranging from superficial mucosal infections to life threatening diseases. The aim of this study was to determine the water quality as well as diversity and antifungal susceptibility of yeasts from two rivers. Yeast levels and physico-chemical parameter data were analyzed by principal component analysis to determine correlations between physico-chemical data and yeast levels. Yeast morphotypes were identified by biochemical tests and 26S rRNA gene sequencing. Disk diffusion antifungal susceptibility tests were conducted. Physico-chemical parameters of the water were within target water quality range (TWQR) for livestock farming. For irrigational use, total dissolved solids and nitrates were not within the TWQR. Yeast levels ranged between 27 ± 10 and 2,573 ± 306 cfu/L. Only non-pigmented, ascomycetous yeasts were isolated. Saccharomyces cerevisiae and Candida glabrata were most frequently isolated. Several other opportunistic pathogens were also isolated. A large number of isolates were resistant to azoles, especially fluconazole, but also to other antifungal classes. Candida species were resistant to almost all the antifungal classes. These water sources are used for recreation and religious as well as for watering livestock and irrigation. Of particular concern is the direct contact of individuals with opportunistic yeast, especially the immune-compromised. Resistance of these yeast species to antifungal agents is a further health concern.


Author(s):  
Gabrielle Nunes da Silva ◽  
Letícia Delduque Alves ◽  
Isabella Escobar dos Santos ◽  
Daniele Maia Bila ◽  
Alfredo Akira Ohnuma Júnior ◽  
...  

This study evaluates the rainwater harvesting system to determine the chemical quality of the water and allocate it for use. Samples were collected in the city of Rio de Janeiro at the points of Direct Precipitation (DP), First Flush (FF) and Reservoir (RR). The methodology involved carrying out an analysis of Ca, Cd, Cu, Na, Ni, Fe, K, Mg, Pb, Zn, conductivity, turbidity, pH and chloride. The R language was used for the principal component analysis, Pearson coefficient correlation, hierarchical cluster analysis, Tukey test and boxplot. The results show that when there is no interference from the catchment surface (DP), the rainwater has a low concentration of metals, although the first millimeters of rain have a concentration above what is permissible in the guidelines issued by the Ministry of Health (Ordinance n° 05/2017). The disposal system (FF) reduced the concentration of pollutants in the RR, but not enough to comply with legislation. It was noted that Ca, K and Na are the main metals found in rainwater. During the dry period, there were significant correlations between the physico-chemical and meteorological parameters. The high concentration of metals in the wet period suggests that rain assists the cleaning of the atmosphere and that most metals are present in the form of aerosols or fine particles suspended in the air. The findings reveal significant indications of acid rain and pre-treatment is recommended to ensure rainwater can be used safely for more mundane purposes.


2008 ◽  
Vol 5 (3) ◽  
pp. 487-492 ◽  
Author(s):  
Arunabh Mishra ◽  
Vasishta Bhatt

A report of physico-chemical and microbial study of the water samples taken from the region nearby Anand district of central Gujarat is presented here. Six water samples are subjected to physico- chemical analysis like pH, TDS, hardness, conductivity, dissolved oxygen and chemical oxygen demand. The MPN count resulted from the bacteriological study of these samples has given the information regarding the suitability of the water for drinking and other domestic applications. The results are analyzed comparatively and conclusions regarding the suitability of the use of such waters are made.


Author(s):  
Souley Maman Sadi ◽  
Addam Kiari Saidou ◽  
Morou Boubé ◽  
Jens B. Aune

The low nutrient availability rainfall patterns regimes are the main constraints to agricultural production in Niger. This was a study of the decomposition and mineralization of nutrients of four types of composts (M1P, M2P, M1H and M2H) in a sandy soil. It was carried out at the experimental N'Dounga station (CERRA Kollo) located about 15 km from Niamey. A randomized blocks design with five repetitions was used. For the evaluation of yield, two doses (1 t ha-1 and 1.5 t ha-1) were applied per millet. Decomposition and mineralization were assessed after burial at 10 cm depth between of a small bag containing 100 g (five small bags / compost). The characterization of the physico-chemical elements of composts samples after incubation has shown that composts are rich in nutrients. Nitrogen ranged from 0.8% to 1.1%, phosphorus from  9.99 mg.kg-1 to 12.76 mg.kg-1 and potassium from 19.94 cmolc dm-3 to 26.26 cmolc dm-3. All four composts are basic (pH> 7). Compost M2H lost more than 80% of its weight during the 10 weeks of the experiment compared to 48% for the M1P. the mineralization of N, P and K is greater at compost M1P (83.6% N, 72.72% P and 89.5% K). This compost also gave the highest yield (1272.5 kg ha-1). The decomposition and mineralization of the main elements (N, P and K) allow the synchronization between the release of nutrients from these composts and the nutrient requirements of millet in a sandy soil.


2021 ◽  
pp. 56-77
Author(s):  
Thyego Silva ◽  
Mariucha Lima ◽  
Teresa Leitão ◽  
Tiago Martins ◽  
Mateus Albuquerque

A hydrochemical study was conducted on the Quaternary Aquifer, in Recife, Brazil. Groundwater samples were collected in March–April 2015, at the beginning of the rainy season. Conventional graphics, ionic ratios, saturation indices, GIS mapping, and geostatistical and multivariate statistical analyses were used to water quality assessment and to characterize the main hydrochemical processes controlling groundwater’s chemistry. Q-mode hierarchical cluster analysis separated the samples into three clusters and five sub-clusters according to their hydrochemical similarities and facies. Principal Component Analysis (PCA) was employed to the studied groundwater samples where a three-factor model explains 80% of the total variation within the dataset. The PCA results revealed the influence of seawater intrusion, water-rock interaction, and nitrate contamination. The physico-chemical parameters of ~30% groundwaters exceed the World Health Organization (WHO) guidelines for drinking water quality. Nitrate was found at a concentration >10 mg NO3−/L in ~21% of the wells and exceeded WHO reference values in one. The integrated approach indicates the occurrence of the main major hydrogeochemical processes occurring in the shallow marine to alluvial aquifer as follow: 1) progressive freshening of remaining paleo-seawater accompanying cation exchange on fine sediments, 2) water-rock interaction (i.e., dissolution of silicates), and 3) point and diffuse wastewater contamination, and sulfate dissolution. This study successfully highlights the use of classical geochemical methods, GIS techniques, and multivariate statistical analyses (hierarchical cluster and principal component analyses) as complementary tools to understand hydrogeochemical processes and their influence on groundwater quality status to management actions, which could be used in similar alluvial coastal aquifers.


2018 ◽  
Vol 69 (1) ◽  
pp. 214-221
Author(s):  
Danut Gabriel Cozma ◽  
Carmen Luiza Costuleanu ◽  
Ion Sandu ◽  
Doina Lutic

The multivariate statistics analysis was used to analyze the correlations between 24 physical and chemical parameters values, for raw and potable water quality characterization, using data collected monthly from a potable water preparation plant during two years, 2015 and 2016. The t-Test (Student) and the Principal Component Analysis were used in order to analyze if there are tight dependences between the analyzed parameters, allowing eventually to purpose the analysis scheme schedule modification.


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