Sea water quality monitoring using remote sensing techniques: a case study in Tangier-Ksar Sghir coastline.

Water quality is an extremely important factor as it affects the ecological balance of ecosystems and the development of the social and economic wellbeing of the countries bordering it. Remote sensing multiconcept helps to understand the natural environment, managing water resources and assessing water pollution on local and regional levels. Landsat 8 data were used to monitor coastal water quality in the region of Tangier-Ksar Sghir. The main purpose of the current study is to establish a mathematical relationship between the amount of light emitted from the water bodies and the measured water parameters. The results permit to create a spatial distribution maps for the water quality parameters. The present work study three water parameters: total suspended solids (TSS), dissolved oxygen (DO), and total dissolved sediments (TDS). Thirty-four sampling points were used to represent water parameters measurements along the coastline. The 75% of the in situ measurements were used to build the statistical models by using the spectral characteristics obtained from the sensors, while the remaining 25% were used for testing the accuracy of the developed equations. For the correlation analysis and the regression development, the Statistical Package of the Social Sciences (SPSS) software was used. The final results of the statistical analysis showed a high correlation between the calculated data and the observed ones with R2 ˃ 0.713 and p value ˂ 0.001. The obtained values showed a high accuracy as well (RMSE ranging between 0.23 and 0.69 and SEE ranging between 0.01 and 0.47). SNAP software and Qgis were used to do the image processing and to create the spatial distribution maps for the water parameters in the coastline of Tangier-Ksar Sghir region.

Preliminary Assessment of Occurrence, Potential Origin, and Human Health Risk of Volatile Organic Compounds in Uncontrolled Springs, North Morocco.

In recent years, with the drastic increase in worldwide pollution rates, considerable attention has been paid to the volatile organic compounds (VOCs) that might lead to serious health problems, e.g., cancer. As there appears to be a notable lack of research on the pollution (specifically, VOCs) of water bodies in Morocco, we aimed to assess the occurrence of VOCs in some uncontrolled springs in the north of Morocco that have not been previously investigated. We also discuss the estimation of health risks posed by ingestion and dermal contact as well as the different potential origins of these pollutants. For this purpose, water samples were collected from twenty-six sampling sites and were analyzed via headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC-MS). Out of the 60 suspected VOCs, a total of 15 compounds belonging to five distinct groups were identified and quantified. Among them, fumigants, solvents, and gasoline hydrocarbons were the most abundant groups, with proportions of 40%, 26.7%, and 20%, respectively. A heatmap clustered the provinces based on their degree of pollution, while a dendrogram was used to classify the studied springs into six main groups. Regarding carcinogenic risk, all the samples were safe for consumption as well as for dermal contact, except for S17, S18, and S8, and S19, which might present a severe threat to inhabitants due to their contents of, respectively, naphthalene (2.1 × 10-3), chloroform (2.5 × 10-4), and cis and trans-dichlropropene (1.61 × 10-4 and 1.11 × 10-4). Our investigation revealed several anthropogenic sources of water contamination, which could aid authorities in limiting contamination spread in water bodies.