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The Impact of RDF Valorization on the Leachate Quality and on Emissions from Cement Kiln (Case Study of a Region in Morocco)
2021
Ouigmane, Abdellah | Boudouch, Otmane | Hasib, Aziz | Ouhsine, Omar | Abba, El Hassan | Isaifan, Rima J. | Berkani, Mohamed
Energy recovery is a sustainable method of municipal solid waste (MSW) management. The co-incineration of refuse derived fuel (RDF) has shown several economic and environmental advantages. The objective of this research is to assess the impact of RDF recovery on leachate quality using leachate tests and calculation of greenhouse gases (GHG) reduction in the kilns of a cement plant. The qualitative results of the eluate show that there is an impact on leachate quality depending on the type of waste. The values of the chemical oxygen demand (COD), biological oxygen demand (BOD5), electrical conductivity and pH of the leachate from the raw waste after 120 hours of leaching are 29.33 gO2/kg DM, 14.00 g O2/kg DM, 4.27 ms/cm and 7.57. On the other hand, the values of the same quality parameters of the eluate generated by the waste without RDF are 19.33 g O2/kg DM, 20.67 g O2/kg DM, 2.77 ms/cm and 7.13; respectively. The calculation of GHG reduction shows that the substitution of 83,000 tonnes per year of petroleum coke by 15% of RDF (25,493 tonnes per year) can reduces 28,970 tCO2 eq.
显示更多 [+] 显示较少 [-]Physics-informed machine learning algorithms for forecasting sediment yield: an analysis of physical consistency, sensitivity, and interpretability
2024
El Bilali, A. | Brouziyne, Youssef | Attar, O. | Lamane, H. | Hadri, A. | Taleb, A.
The sediment transport, involving the movement of the bedload and suspended sediment in the basins, is a critical environmental concern that worsens water scarcity and leads to degradation of land and its ecosystems. Machine learning (ML) algorithms have emerged as powerful tools for predicting sediment yield. However, their use by decision-makers can be attributed to concerns regarding their consistency with the involved physical processes. In light of this issue, this study aims to develop a physics-informed ML approach for predicting sediment yield. To achieve this objective, Gaussian, Center, Regular, and Direct Copulas were employed to generate virtual combinations of physical of the sub-basins and hydrological datasets. These datasets were then utilized to train deep neural network (DNN), conventional neural network (CNN), Extra Tree, and XGBoost (XGB) models. The performance of these models was compared with the modified universal soil loss equation (MUSLE), which serves as a process-based model. The results demonstrated that the ML models outperformed the MUSLE model, exhibiting improvements in Nash–Sutcliffe efficiency (NSE) of approximately 10%, 18%, 32%, and 41% for the DNN, CNN, Extra Tree, and XGB models, respectively. Furthermore, through Sobol sensitivity and Shapley additive explanation–based interpretability analyses, it was revealed that the Extra Tree model displayed greater consistency with the physical processes underlying sediment transport as modeled by MUSLE. The proposed framework provides new insights into enhancing the accuracy and applicability of ML models in forecasting sediment yield while maintaining consistency with natural processes. Consequently, it can prove valuable in simulating process-related strategies aimed at mitigating sediment transport at watershed scales, such as the implementation of best management practices.
显示更多 [+] 显示较少 [-]Morocco's coastal aquifers: Recent observations, evolution and perspectives towards sustainability
2022
Ez-zaouy, Yassine | Bouchaou, Lhoussaine | Saad, Aicha | Hssaisoune, Mohammed | Brouziyne, Youssef | Dhiba, Driss | Chehbouni, Abdelghani
During the last decades, the coastal areas of Morocco have witnessed an intense socioeconomic development associated with a continuous population growth and urban extension. This has led to an overexploitation of coastal aquifers leading to a degradation of their water quality. In order to obtain large scale overview on the quality status of Morocco's coastal aquifers (MCA) to assist national water managers to make informed decisions, a comprehensive scrutinization of the MCA against common indicators and using unified methods is essential. In this study, databases from thirteen MCA were analyzed, using multivariate statistical approaches and graphical methods in order to investigate the degree of mineralization in each aquifer and to identify the main salinization processes prevailing in groundwater. The results showed that the dominant groundwater types are Na–Cl, Ca–Mg–Cl, Ca–Mg–SO₄, Ca–Mg–HCO₃ and Ca–HCO₃–Cl. The Gibbs diagram and the seawater contribution (0–37%) indicate that the mineralization is mainly due to the seawater intrusion and water-rock interaction. The salinity degree diagram illustrates that almost all groundwater samples are located in the moderate to very saline zone, indicating that MCA are recharged by water from variable sources. The groundwater quality assessment shows a deterioration, particularly by seawater intrusion and significant nitrate pollution. The temporal evolution confirm that the MCA are influenced by seawater namely in the Atlantic part. The Wilcox and USSL diagram indicate that the majority of sampled water are unsuitable for irrigation uses. In addition, and by referring to the WHO and the Moroccan standards for water potability, large number of samples from the groundwaters of the MCA is not fully adequate for drinking purposes. A set of management actions (e,g., artificial recharge) are proposed in order to mitigate the effect of groundwater overexploitation and seawater intrusion to ensure the sustainability of MCA.
显示更多 [+] 显示较少 [-]Health and ecological risk assessment based on pesticide monitoring in Saïss plain (Morocco) groundwater
2021
Berni, Imane | Menouni, Aziza | El Ghazi, Ibrahim | Godderis, Lode | Duca, Radu-Corneliu | Jaafari, Samir El
In many countries, including Morocco, groundwater contamination with pesticides such as globally banned organochlorides (e.g., dichlorodiphenyltrichloroethane (DDT)) and some accredited organophosphates and pyrethroids poses ecological and human health risks. To assess these risks, we herein monitored pesticides in Saïss plain groundwater (Morocco) during the summer of 2017 and the winter of 2018 using polar organic chemical integrative samplers. The two types of passive samplers were deployed in 22 traditional wells for 14–20 days and subjected to solid-phase extraction. The extracts were analyzed by gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry using a multiresidue method, and 27 pesticides were detected in total. In the summer campaign, 22 pesticides with individual concentrations ranging from <limit of quantitation (LOQ) to 243.1 ng L⁻¹ were identified, whereas 17 compounds with concentrations ranging from <LOQ to 53.8 ng L⁻¹ were detected in the winter campaign. In the summer period, the maximum individual concentrations of chlorothalonil, DDT, and α-hexachlorocyclohexane (α-HCH) equaled 111.7, 36.1, and 22.3 ng L⁻¹, respectively, with the respective values for the winter period equaling 18.14, 16.62, and 22.2 ng L⁻¹. Health risk assessment indicated that the carcinogenic α-HCH, β-HCH, DDT, and dichlorodiphenyldichloroethylene present in groundwater may also contaminate drinking water and thus pose a threat to human health, particularly to that of infants and children. Further analysis revealed that the Saïss aquifer presents a high ecological risk. Thus, the monitoring of pesticides in groundwater by passive sampling was effective and could be combined with human health and ecological risk assessment to develop ways of reducing human and environmental exposure to pesticides.
显示更多 [+] 显示较少 [-]Microplastic ingestion by Atlantic horse mackerel (Trachurus trachurus) in the North and central Moroccan Atlantic coast between Larache (35°30′N) and Boujdour (26°30′N)
2021
Maaghloud, Hind | Houssa, Rachida | Bellali, Fatima | El Bouqdaoui, Karima | Ouansafi, Soukaina | Loulad, Safia | Fahde, Abdelilah
Horse mackerel is a semi-pelagic species found in abundance in the Moroccan coasts and occupies the first ranks in the catches landed by the coastal fleet. In this study, we investigated the ingestion of Polyamide, Acrylic and Polystyrene by Atlantic horse mackerel, in the Moroccan Atlantic coastal area located between Larache (35°30′N) and Boujdour (26°30′N). The objective is to map the spatial distribution of horse Mackerel containing microplastics (MPs) in their stomachs and identify hot spot areas. We also aim to verify the most ingested polymer by this fish characterized by significant daily vertical migrations. The results show that the three studied polymers were detected in the stomach contents of more than 73% of studied fishes. The hot spot areas are located more in the northern part where urbanization and fishing activity are important. Polyamide, the densest polymer, is the most abundant (86% of cases), followed by acrylic. These two polymers were found in association in 47% of cases. No correlation between the presence of MPs in the stomach contents and the size of the individual fishes was noted. Interestingly, the group of mature specimens ingested more MPs than the immature group.
显示更多 [+] 显示较少 [-]Bacteriological and geochemical features of the groundwater resources: Kettara abandoned mine (Morocco)
2019
Zouhri, Lahcen | El Amari, Khalid | Marier, David | Benkaddour, Abdelfattah | Hibti, Mohamed
Waste water of the Kettara village, as well as the abandoned tailings, constitute a potential environmental issue with direct consequences on air, soil, water resources qualities and, on human health. In this paper, experimental investigations examine the environmental impact which is induced by the wastewater, mine tailings and the lithological factors of rocks. This multidisciplinary research allows to i) understand the transfer of the Metallic Trace Elements (selenium, arsenic, nickel and zinc) and sulfate ions in the fractured shales media, ii) to assess the water potability by using the microbiological analysis. The microbiological results reveal the domestic impact by the presence of several kinds of bacteria in the groundwater resources: E. coli, Fecal coliforms, Total coliforms, Enterococci, Mesophilic Aerobic Flora, Sulphite-reducing bacteria and Salmonella.Selenium, arsenic and the bacteriological contamination of the groundwater could be explained by five kinds of factors: i) the geological formations and the nature of the hydrogeological system (unconfined layer), ii) the groundwater flow, the hydraulic relation between the hydrogeological wells and, the fractures network in the shale aquifer. The piezometric map allows to highlight the groundwater flow from the North-East to North-West and to the South-West, the drainage axis towards the P21 well and the presence of the dividing axis in the contaminated zone by the arsenic, iii) the absence of the unhealthy habitats with permeable traditional septic tanks in the village; iv) the transfer of the spreading animal excrements from the soil to groundwater and, v) the migration of the wastewater towards downstream of the groundwater flow. The presence of the reed beds could explain the reduction of bacteria in the hydrogeological wells of the study area.
显示更多 [+] 显示较少 [-]Groundwater assessment and environmental impact in the abandoned mine of Kettara (Morocco)
2017
Moyé, Julien | Picard-Lesteven, Tanguy | Zouhri, Lahcen | El Amari, Khalid | Hibti, Mohamed | Benkaddour, Abdelfattah
Many questions about the soil pollution due to mining activities have been analyzed by numerous methods which help to evaluate the dispersion of the Metallic Trace Elements (MTE) in the soil and stream sediments of the abandoned mine of Kettara (Morocco). The transport of these MTE could have an important role in the degradation of groundwater and the health of people who are living in the vicinity. The present paper aims to evaluate the groundwater samples from 15 hydrogeological wells. This evaluation concerns the hydrogeological parameters, pH, Electrical conductivity, temperature and the groundwater level, and the geochemical assessment of Mg, Ca, Ti, Cr, Mn, Fe, Co, Ni, Zn, Cu, As, Se, Cd, Sb, Tl and Pb. Furthermore, the Metallic Trace Elements are transported in the saturated zone via the fractures network. The groundwater flow is from the north-east to south-west. The spatial distribution of As, Fe, Zn and Mn is very heterogeneous, with high values observed in the north, upstream, of the mine site. This distribution is maybe related to: i) the existence of hydrogeological structures (dividing and drainage axes); ii) the individualization of the fractures network that affects the shaly lithostratigraphical formation; iii) the transport of the contaminants from the soil towards groundwater; and iv) interaction water/rocks. Some MTE anomalies are linked to the lithology and the fracturation system of the area. Therefore, the groundwater contamination by Arsenic is detected in the hydrogeological wells (E1 and E2). This pollution which is higher than guideline standards of Moroccan drinking water could affect the public health. The hydrogeological and geochemical investigations favor the geological origin (mafic rocks) of this contamination rather than mining activities.
显示更多 [+] 显示较少 [-]Multiple stable isotopes and geochemical approaches to elucidate groundwater salinity and contamination in the critical coastal zone: A case from the Bou-areg and Gareb aquifers (North-Eastern Morocco)
2022
Elmeknassi, Malak | Bouchaou, Lhoussaine | El Mandour, Abdennabi | Elgettafi, Mohammed | Himi, Mahjoub | Casas, Albert
Mediterranean areas are characterized by complex hydrogeological systems, where water resources are faced with several issues such as salinity and pollution. Fifty-one water samples were gathered from the Bou-areg coastal and the Gareb aquifers to evaluate the source of water salinity and to reveal the processes of the different sources of pollution using a variety of chemical and isotopic indicators (δ²H–H2O, δ¹⁸O–H2O, δ³⁴S–SO4, and δ¹⁸O–SO4). The results of the hydrochemical analysis of water samples show that the order of dominated elements is Cl⁻ > HCO₃⁻ > SO4₂⁻ > NO₃⁻ and Na⁺ > Ca²⁺ > Mg²⁺ > K⁺ and evidenced extremely high salinity levels (EC up to 22000 μS/cm). All samples exceeded the WHO drinking water guidelines, making them unfit for human consumption. Ion ratio diagrams, isotopic results, and graphical comparing indicate that the mineralization of groundwater in the area, is controlled by carbonate dissolution, evaporite dissolution, ion exchange, and sewage invasion. The return of irrigation water plays a significant role as well in the groundwater recharge and its mineralization by fertilizers mainly. Evaporites (Gypsum), sewage, and fertilizers constitute the main sources of sulfates in the investigated water resources. These scientific results will be an added value for decision-makers to more improve the sustainable management of groundwater in water-stressed regions. The use of chemical and isotopic tracers once again shows their relevance in such zones where systematic monitoring is lacking.
显示更多 [+] 显示较少 [-]Lead-based paints and children's PVC toys are potential sources of domestic lead poisoning – A review
2019
Njati, Shukuru Yusufu | Maguta, Mihayo Musabila
Lead (Pb) both in paints and children's Polyvinyl chloride (PVC) toys is a major public health concern which has attracted attention of the international community. Concentrations of Pb both in lead-based paints and children's PVC toys have been assessed through various studies across the globe. Therefore, the purpose of this article was to summarize the results reported in these studies and provide some comprehension on their implications to human health for law enforcement as well as for awareness raising to the general public. Highlights on identified gaps have been provided to pave ways for further research interventions in order to establish comprehensive information on the subject.Regardless of regulatory limits on the content of lead, both in paints and children's PVC toys existing in different countries in the world, some of the reviewed articles have revealed significant levels of lead in these two items far above the permissible limits.High lead levels in paints have been recorded in China (116,200 ppm), Cameroon (500,000 ppm), South Africa (189,000 ppm), Tanzania (120,862.1 ppm), Uganda (150,000 ppm), Thailand (505,716 ppm) and Brazil (170,258.4 ppm) just to mention a few.Lead poisoning cases in children have been reported in several countries including France, Morocco, South Africa and United States. Countries where high levels of lead in children's PVC toys have been recounted include; China (860,000 ppm), South Africa (145,000 ppm), United States (22,550 ppm), Thailand (4,486.11 ppm), Palestine (6,036 ppm) and India (2,104 ppm).Awareness raising among parents is vital to impart them with knowledge on the matter so that they can take strenuous measures to protect their children from lead poisoning emanating from playing with toys and paint dust. Law enforcement on phasing out lead-based paints and control of lead content in children's PVC toys worldwide is also highly recommended.
显示更多 [+] 显示较少 [-]Assessment of seasonal and spatial variation responses of integrated biomarkers in two marine sentinel bivalve species: Agadir Bay (Southern of Morocco)
2022
Chahouri, Abir | Agnaou, Mustapha | El Hanaoui, Mohamed | Yacoubi, Bouchra | Moukrim, Abdellatif | Banaoui, Ali
The present study aims to assess the effects of contamination of the Agadir bay coasts using bivalves as a biomonitoring sentinel species. Seasonal variations of biochemical composition in terms of total protein content and oxidative stress biomarkers including glutathione-S-transferase, malondialdehyde, catalase and acetylcholinesterase were evaluated in the soft tissues of Scrobicularia plana and Donax trunculus specimens. The latter were collected from two sites in Agadir bay during two-year span (2018–2020). The Integrated Biomarker Response Index (IBR) was performed to classify the stress response in both species and to assess the level of exposure to xenobiotics. The data showed maximum annual values of acetylcholinesterase and malondialdehyde for Donax trunculus in Agadir beach (AG) with 6.25 nmol/mn/mg and 3 nmol/mg of protein, respectively. Those of catalase and glutathione-S-transferase for Scrobicularia plana in Oued Souss estuary (OS) were of 4.41 μmol/mn/mg and 14.43 nmol/mn/mg of protein, respectively. The studied species are considered good indicators in aquatic ecosystems.
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