scholarly journals Surface and Groundwater Characteristics within a Semi-Arid Environment Using Hydrochemical and Remote Sensing Techniques

Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 277
Author(s):  
Abdellatif Rafik ◽  
Mohammed Bahir ◽  
Abdelaziz Beljadid ◽  
Driss Ouazar ◽  
Abdelghani Chehbouni ◽  
...  

The understanding of hydro systems is of great importance in monitoring quantitative and qualitative changes in water resources. The Essaouira region at the edge of the Moroccan Atlantic Ocean is subject to a semi-arid climate. The decrease in rainfall as a result of climate change and the increase in the exploitation of surface and groundwater have disrupted the stability of these resources and threaten the socio-economic and environmental balance in the area under investigation. Climate scenarios estimate that precipitation will decrease by 10–20% while warming increases by 3 °C over the next 30 years. The physico-chemical parameters studied show that the evolution of the pH and temperature of the groundwater remained stable with a neutral (pH ≈ 7) and a hypothermal character (T < 30 °C). For the electrical conductivity, it showed an increasing trend from 2017 to 2020. A hydrochemical approach showed that the groundwater mineralization was controlled by the dissolution of evaporites and carbonates, by cation exchange processes, and by seawater contamination. A groundwater assessment for drinking use was made by comparing the concentrations of the chemical elements with the standards set by the World Health Organization. The results obtained show that the groundwater from the aquifers studied requires treatment before being consumed, in particular for Cl− and SO42−. Furthermore, the groundwater quality for irrigation was evaluated based on the parameters Na% and Sodium Adsorption Ratio (SAR). The results showed that the groundwater was adequate for agricultural purposes, especially for the plants that adapt to high salinity. The monitoring of surface water by processing the satellite images via the calculation of the normalized difference water index (NDWI) showed an increase in water surface areas in the region following the commissioning of two large dams (Zerrar and Igouzoullene). Despite the installation of these hydraulic structures, a drop of 4.85 km2 in water surface area was observed beyond 2016. This situation requires intervention in order to preserve this vital resource.

2016 ◽  
Vol 40 (2) ◽  
pp. 152-155 ◽  
Author(s):  
TE Shishniashvili ◽  
NN Suladze ◽  
VV Margvelashvili

Objectives: To study the influence of environmental pollution on the mineralization of dental hard tissues by using biosubstrates: teeth and hair. :Study design: At the first stage epidemiological survey was conducted in polluted and less polluted areas of Tbilisi (Georgia). We studied 525 children aged 3 and 4 years. Caries prevalence and intensity was defined by the methodology of World Health Organization. At the second stage the chemical elements content was studied in hair and teeth hard tissues of 24 children by X - ray fluorescent spectroscopy method. Results: The prevalence of dental caries in the polluted region was 46%, caries intensity − 1.92 (± 2.842). In the less polluted region prevalence was 37%, caries intensity − 1.47 (± 2.571). These data are statistically reliable (p &lt; 0.05). The study of hair and tooth tissues showed that the toxic elements (Pb, Hg, Sn, Ti) content in these tissues was higher in environmentally unfavorable than in favorable conditions. Conclusion: Hair and dental tissues can be used as indicators of environmental pollution. Our survey showed that toxic elements content in dental hard tissues was higher and the level of essential elements was less in polluted than in less polluted areas of Tbilisi.


2020 ◽  
Vol 24 (3) ◽  
pp. 511-517
Author(s):  
O.B. Ovonramwen

Physicochemical analyses of surface and groundwater samples from eleven different locations in Ugbomro and Iteregbi, Delta State, Nigeria were sampled and analyzed for physicochemical parameters according to standard methods for the examination of water and wastewater. The following  mean and standard deviation were obtained from the groundwater of the communities: temp (oC) 22.46 ± 0.50 and 23.23 ± 0.99, pH 6.63 ± 0.68 and6.69 ± 0.24, dissolved oxygen (DO) (mg/L) 5.91 ± 0.46 and 5.73 ± 0.46, chemical oxygen demand (COD) (mg/L) 4.24 ± 0.01 and 4.43 ± 0.10, biochemical oxygen demand (BOD) (mg/L) 3.51 ± 0.38 and 3.84 ± 0.21, Turbidity (NTU) 1.22 ± 1.07 and 3.56 ± 0.77, electrical conductivity (EC) (μs/cm) 748.9 ± 215.79 and 786.67 ± 226.77, color (TCU) 1.22 ± 2.12 and 6.11 ± 2.11, total alkalinity (TA) (mg/L) 6.22 ± 7.38 and 14.11 ± 11.19, HCO3- (mg/L) 6.22 ± 7.38 and 14.11 ± 11.19, NO3 - (mg/L) 1.13 ± 0.62 and 2.89 ± 1.25, total solids (TS) (mg/L) 489.09 ± 180.17 and 664.95 ± 373.37, total suspended solids (TSS) (mg/L) 32.25 ± 24.29 and 123.86 ± 82.79, total dissolved solids (TDS) (mg/L) 456.78 ± 163.73 and 542.20 ± 450.66, Cl- (mg/L) 21.20 ± 3.20 and 20.10 ± 3.89, total hardness (TH) (mg/L) 26.67 ± 22.83 and 46.78 ± 36.17, Na (mg/L) 1.26 ± 0.06 and 1.16 ± 0.04, K (mg/L) 0.04 ± 0.01 and 0.06 ± 0.03, Mg (mg/L) 4.32 ± 3.23 and 6.96 ± 5.49, Ca (mg/L) 8.68 ± 9.35 and 18.12 ± 13.71 respectively. The results obtained were subjected to statistical analysis and compared with the standard set by the Standards Organization of Nigeria (SON) and the World Health Organization (WHO) for water samples. Some of the parameters did not meet the standards, hence the need for treatment. The present physio-chemical analyses of surface and groundwater quality of the two neighboring university areas, Ugbomro and Iteregbi, were done to assess the environmental status of  the environment before socio-economic impacts. Keywords: physicochemical, surface water, groundwater, water quality


2017 ◽  
Vol 68 (2) ◽  
pp. 420-423
Author(s):  
Abdenour Sedrati ◽  
Belgacem Houha ◽  
Gheorghe Romanescu ◽  
Ioan Gabriel Sandu ◽  
Daniel Constantin Diaconu ◽  
...  

The El-Meita plateau is situated in the south of the city of Khenchela and it is delimited by the Saharan Atlas to the north and Chott Melghir to the south. The agricultural importance and the high productivity of this region are provided by the aggressive use of chemical fertilizers. For this reason, we have decided to conduct this study, considering that all water bodies � superficial waters and groundwaters � record significant amounts of NO3-, NO2-, NH4-, heavy metals (Pb, Cd, Cu, Zn and Hg) and other major chemical elements. The campaign of collecting the 30 water samples took place in the month of May 2016. The chemical analyses were conducted in the Lacip ain-Mlila laboratory in Algeria. Findings show a contamination of groundwater by nitrates and lead; values exceed the maximum limits approved by World Health Organization (WHO). TDS were also found in high concentrations, which limit the use of water for some agricultural cultures, but which can be admissible for certain salinity-resistant species.


2020 ◽  
Vol 18 (6) ◽  
pp. 1050-1064
Author(s):  
Isabel Cipriani-Avila ◽  
Jon Molinero ◽  
Eliza Jara-Negrete ◽  
Miren Barrado ◽  
César Arcos ◽  
...  

Abstract Chemical elements, which are present in drinking water, could vary due to water sources, treatment processes or even the plumbing materials. Most of these elements do not represent a threat, while others, such as heavy metals, have been proven to cause harmful effects over human and aquatic wildlife. In this study, the quality of drinking water in three cities in Ecuador, Quito, Ibarra and Guayaquil was assessed through a multielement analysis and the heavy metal pollution index (HPI). A total of 102 drinking water samples and six natural water samples were collected and analyzed. Within the scope of analysis, results show that water quality complies with local and international guidelines. HPI did not show significant differences in the water that is supplied to the different neighborhoods of the three cities studied. However, actions should be taken to protect the sources of water, especially in Guayaquil, due to the presence of lead and chromium. For instance, lead was found in 2.8% of the samples in concentrations above World Health Organization (WHO) recommended values. Thus, we suggest to assessing the quality and age of the plumbing system within the whole country, in order to avoid drinking water contamination with heavy metals.


2021 ◽  
Vol 63 (9) ◽  
pp. 822-828
Author(s):  
Faruk Karaca ◽  
İlhan Can

Abstract International organizations such as the World Health Organization (WHO) and the International Labor Organization (ILO) have called for an end to the use of asbestos and its derivatives in all sectors, primarily due to the negative effects on human and environmental health. For this reason, manufacturing and use of asbestos linings are also prohibited in most developed countries. For this purpose, there are many studies in the literature on the development and research of nonasbestos linings. In the literature, topics such as material content, production, cost, braking performances and mechanical properties of composite linings are commonly encountered. With the technology in the developing world, the working conditions of vehicle elements are getting more difficult. For this reason, during braking, the amount of energy required to be damped against the unit area in the pad surfaces increases, and since the lining surface areas get smaller, the operating temperatures exceed the limits of the material components. Under these conditions, the design of the lining material content is extremely important, taking into account parameters such as load and operating conditions, in order to slow down or stop the vehicle safely. In this study, the braking performance, mechanical and tribological properties of the samples obtained from a number of production processes such as mixing, pre-shaping and pressing of the materials by altering the particle sizes (50 μm, 75 μm and 125 μm) of the filler and friction materials used together with powdered alumina (Al2O3) were investigated. The most suitable parameters were determined as lining material for the samples obtained.


2020 ◽  
Vol 2 ◽  
pp. 65-70 ◽  
Author(s):  
Malik H. Kheder ◽  
Hanaa N. Azeez ◽  
Firas M. Al-Jomaily

Cosmetics play an important role of human external appearance, its products used to alter or enhance the facial appearance or the body and skincare, currently worldwide consumed with frequently use increasing the human body exposure to the various chemical elements including radioactive substances. This research aimed to measure the concentrations of alpha emitters, and the annual effective dose AED resulting from radon intake. LR-115 track detector used to measure radon, and radium concentrations in 20 cosmetics samples selected from markets. In this work the concentrations of radon in the samples found to vary from 9.876 to 30.97 Bq/m3 with 22.11 Bq/m3 a mean value, this mean value is a very small than 100 Bq/m3 the reference level limits of the World Health Organization (WHO). The annual radon effective dose varied between 0.249–0.781 mSv/y which is within the range of 0.2-10 mSv/y (UNSCEAR). Radium contents vary between 0.041–0.249 Bq/Kg with 0.115 Bq/Kg as a mean value. This work identified law measured concentrations of radionuclide present in cosmetics showed its safe for use


2009 ◽  
Vol 14 (3) ◽  
pp. 3-6
Author(s):  
Robert J. Barth

Abstract “Posttraumatic” headaches claims are controversial because they are subjective reports often provided in the complex of litigation, and the underlying pathogenesis is not defined. This article reviews principles and scientific considerations in the AMAGuides to the Evaluation of Permanent Impairment (AMA Guides) that should be noted by evaluators who examine such cases. Some examples in the AMA Guides, Sixth Edition, may seem to imply that mild head trauma can cause permanent impairment due to headache. The author examines scientific findings that present obstacles to claiming that concussion or mild traumatic brain injury is a cause of permanent headache. The World Health Organization, for example, found a favorable prognosis for posttraumatic headache, and complete recovery over a short period of time was the norm. Other studies have highlighted the lack of a dose-response correlation between trauma and prolonged headache complaints, both in terms of the frequency and the severity of trauma. On the one hand, scientific studies have failed to support the hypothesis of a causative relationship between trauma and permanent or prolonged headaches; on the other hand, non–trauma-related factors are strongly associated with complaints of prolonged headache.


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