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Water quality index (WQI) is the primary method applied to characterize water quality in the world. The current study employed the statistical analysis and multilayer perceptron (MLP) approaches for predicting groundwater quality in the Ghiss-Nekkor aquifer, northeast of Al Hoceima, Morocco. Fifty sampled groundwater were identified and analyzed for major anions and cations throughout May 2019. Several physicochemical parameters of all the samples were identified in this investigation, such as TDS, pH, EC, Na, K, Ca, Mg, HCO3, NO3, Br, SO4, and Cl. The entropy-weighted groundwater quality index (EWQI) was calculated from these parameters. The WQI procedure determined the suitability of groundwater for consumption. The WQI value varied from 90.98 to 337.28. The EC, TDS, WQI, and Cl- spatial distribution showed that EC and Cl- are associated with poor groundwater quality. A single sample (W16) represented unsuitable water for drinking purposes and offered a WQI value of 337.28, indicating poor drinking quality due to seawater intrusion, overexploitation, and harsh weather conditions. The majority of the values obtained for the parameters exceeded the recommended limit of the World Health Organization (WHO)’s guidelines for consumption. The findings show that using parameters is a straightforward method for predicting water quality indexes with sufficient and suitable precision. The MLP model shows good predictive performances in terms of the coefficient of determination R2, mean absolute error (MAE), and root-mean-square error (RMSE) with values of 0.9885, 5.8031, and 4.7211, respectively. The ANN approach was applied to develop a model that can accurately predict WQI utilizing mineralization, TH, NO3, and NO2 as inputs. The MAE for the model’s performance was calculated to be 4.72. A Bland–Altman test was used to validate that the model is suitable. Following the test, it was determined that the model is appropriate for predicting WQI, with an error of just 0.1%.

Soil erosion is an increasingly issue worldwide, due to several factors including climate variations and humans’ activities, especially in Mediterranean ecosystems. Therefore, the aim of this paper is: (i) to quantify and to predict soil erosion rate for the baseline period (2000–2013) and a future period (2014–2027), using the Revised Universal Soil Loss Equation (RUSLE) and the Soil and Water Assessment Tool (SWAT) model in the R’Dom watershed in Morocco, based on the opportunities of Remote Sensing (RS) techniques and Geographical Information System (GIS) geospatial tools. (ii) we based on classical statistical downscaling model (SDSM) for rainfall prediction. Due to the lack of field data, the model results are validated by expert knowledge. As a result of this study, it is found that both agricultural lands and bare lands are most affected by soil erosion. Moreover, it is showed that soil erosion in the watershed was dominated by very low and low erosion. Although the area of very low erosion and low erosion continued to decrease. Hence, we hereby envisage that our contribution will provide a more complete understanding of the soil degradation in this study area and the results of this research could be a crucial reference in soil erosion studies and also may serve as a valuable guidance for watershed management strategies.

This article is devoted to the analysis of the confinement effects of the neutral dynamics generated by a short-gap (0.5 mm) discharge inside three different microcavity geometries (cylinder, cube, and bricklike) filled with air at atmospheric pressure (760 Torr) and ambient temperature (293 K). The discharge is modelled by two mathematical functions representing the Joule heating and the momentum transfer between charged and neutral particles. Their spatio-temporal evolution are taken from experimental results with 470 ns for the duration and 13.5 W for the maximum injected power. The neutral gas evolution is described by the classical transport equations and solved by a powerful numerical monotonic upstream-centered scheme for conversion laws. Because of the microcavity dimensions considered, particular care has been used in the analysis of the thermal and hydrodynamics boundary layers which condition the gas–solid interaction in terms of viscous slip effects and thermal exchanges. The results presented show the microcavity geometry effects on the distribution of the initial cylindrical pressure wave as soon as it reaches the lateral walls. They show the specificity of the cube and bricklike microcavities due to the delayed reflections on the corners leading to a more heterogeneous gas behavior than in the case of the cylindrical microcavity. We also discuss the specific gas behaviors near the wall resulting from heat exchange and viscous stress.

The objective of the study is to raise awareness of the effect of anthropogenic activity on groundwater in the urban area, water samples were collected from 12 wells in the area in April and September 2019.  From these samples, pH and conductivity were determined using a pH meter/conductivity meter. From these samples, pH and conductivity were determined using a pH meter/conductivity meter, while heavy metal concentrations (Mn, Fe, Pb, Cu and AL) were determined by atomic analysis and ICP-MS. The study showed that groundwater in the study area is (0.01mg/l<Mn2+<0.06 mg/l) and contains (0.14mg/l<Cu2+<0.03 mg/l), (0.02mg/l<Fe2+<0.4 mg/l), (0.02mg/l<Zn2+<1.8mg/l) and (0.01mg/l<AL3+<0.05mg/l). These concentrations are above the permissible limits recommended by the World Health Organization (0.05, 0.2, 0.3, 5 and 0.2 mg/l, respectively; p > 0.05). Bacteriological analyses show that the vast majority of the wells studied in the Ben Taib area harbour high densities of Faeceal coliform (0 to more than 420 CFU/100ml) and Fecal Streptococci (0 to over 25 CFU/100ml). The presence of these high quantities of pathogens, which are indicators of pollution and bacteriological contamination by wastewater, could be due to anthropic activities.

The groundwater of the Ghis-Nekor aquifer (Central Rif of Morocco) is the main water resource used by the inhabitants for agricultural and domestic purposes. However, its low quality may affect the health of the consumer and weaken agricultural production. The existence of the WWTP at the level of this plain, makes it a probable source of pollution for these groundwater and requires urgent water managers’ intervention. Groundwater pollution in this area may be related to natural, anthropogenic and undefined sources (agricultural and industrial activities). To assess the impact of WWTP effluent on this aquifer, ten well water samples were collected upstream and downstream of this WWTP in 2018, and then analysed for physicochemical quality. Multivariate and principal Component Analysis (PCA) of the results obtained revealed two main components, in which the largest source of total variation being F1 presented at 54.75%. The PCA has visualized two groups that distinguish slightly mineralized well waters upstream to moderately from other wells downstream of the WTTP that are highly mineralized. Generally, the groundwater in the study area is characterized by high levels of salinization. The results of this study may be useful for monitoring and managing groundwater pollution in the study area.

Together with geological survey data, satellite imagery provides useful information for geological mapping. In this context, the aim of this study is to map geological units of the Saka region, situated in the northeast part of Morocco based on Landsat Oli-8 and ASTER images. Specifically, this study aims to: (1) map the lithological facies of the Saka volcanic zone, (2) discriminate the different minerals using Landsat Oli-8 and ASTER imagery, and (3) validate the results with field observations and geological maps. To do so, in this study we used different techniques to achieve the above objectives including color composition (CC), band ratio (BR), minimum noise fraction (MNF), principal component analysis (PCA), and spectral angle mapper (SAM) classification. The results obtained show good discrimination between the different lithological facies, which is confirmed by the supervised classification of the images and validated by field missions and the geological map with a scale of 1/500,000. The classification results show that the study area is dominated by Basaltic rocks, followed by Trachy andesites then Hawaites. These rocks are encased by quaternary sedimentary rocks and an abundance of Quartz, Feldspar, Pyroxene, and Amphibole minerals.