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Eutrophication has led to the widespread occurrence of cyanobacterial blooms. Toxic cyanobacterial blooms with high concentrations of microcystins (MCs) have been identified in the Lalla Takerkoust reservoir in Morocco. The objective of this study was to evaluate the efficiency of the Multi-Soil-Layering (MSL) ecotechnology in removing natural cyanobacterial blooms from the lake. Two MSL pilots were used in rectangular glass tanks (60 × 10 × 70 cm). They consisted of permeable layers (PLs) made of pozzolan and a soil mixture layer (SML) containing local soil, ferrous metal, charcoal and sawdust. The main difference between the two systems was the type of local soil used: sandy soil for MSL1 and clayey soil for MSL2. Both MSL pilots effectively reduced cyanobacterial cell concentrations in the treated water to very low levels (0.09 and 0.001 cells/mL). MSL1 showed a gradual improvement in MC removal from 52 % to 99 %, while MSL2 started higher at 90 % but dropped to 54% before reaching 86%. Both MSL systems significantly reduced organic matter levels (97.2 % for MSL1 and 95.8 % for MSL2). Both MSLs were shown to be effective in removing cyanobacteria, MCs, and organic matter with comparable performance. [Display omitted] • Cyanobacterial cell removal by Multi-Soil-Layering (MSL) ranged from 99 % to 100 % • Greater degradation capacity of MC-LR in MSL1 (sandy soil) and MSL2 (clay soil) • MC-YR variant was most persistent in substrate of both MSL systems • qPCR detected degrading bacteria in both MSL systems • MSL1 had significant abundance of mlrA gene copies and degrading bacteria [ABSTRACT FROM AUTHOR]

This study aims to preserve and improve the durability of earthen buildings in rural areas of Morocco, particularly in the Al Haouz province of the Marrakech-Safi region. In this paper, a survey was conducted to identify defects in earthen building materials and investigate factors that lead villagers to use cement over traditional earth-based construction methods. To propose solutions to these shortcomings, mineralogical, physicochemical, and geotechnical studies were conducted on four soils commonly used as rural building materials. Subsequently, some corrections were implemented in the treatment of raw materials and the production process of compressed earth blocks (CEBs), which were then subjected to mechanical, physical, and morphological characterization. The findings of this study revealed several building pathologies in earthen construction in this region, including ceiling water leaks, formulations made, and cracks. Research shows that the key factors influencing the durability of building materials are particle size distribution, mineralogy composition, moisture content, and construction process. • Preserving and improving the durability of earthen buildings in rural areas. • Building pathologies in the earthen construction in Al Haouz region. • Mineralogical, physicochemical, and geotechnical studies of clayey soils. • Relationship between soil properties and building pathologies. [ABSTRACT FROM AUTHOR]

• Evaluating different unstudied Easter Moroccan clayey materials for potential industry usage. • The impact of raw materials' properties and industrial processing on the characteristics of the final product. • Investigation of mineralogical, chemical, and physical properties of the raw materials. • Experimental measurement of the thermal and mechanical properties of the produced bricks. • Comparative study between laboratory and industry scale bricks. This study aims to the valorization of soil materials (unfired and fired) for sustainable buildings in eastern Morocco. To make this study more representative, four clay soils from different areas were considered in this investigation (i.e., Zaio, Oujda, Lota, and Midar). Geotechnical tests revealed that all samples exhibit a high clay content and medium plasticity. X-ray diffraction, thermal gravimetric analysis and energy dispersive X-ray spectroscopy of the soils showed the presence of quartz, calcite and several clay minerals. The significant clay content and the high density of the bricks (1589–1713 kg.m−3) have an effect on the properties of the unfired solid clay brick. Experimental results have shown that the thermal conductivity and compressive strength of the unfired solid clay brick vary between (0.77–1.07 W.m−1K−1) and (1.7–2.4 MPa) respectively. The cavities and firing process for fired hollow clay bricks contributed to the increase in thermal and mechanical resistance of the bricks by (0.19–0.4 W.m−1K−1) and (2.9–5 MPa) respectively. After identification of all the samples, the authors' justified choice was to use the soil collected from the Lota site for the ANSYS-Fluent hybrid wall case studies. In comparison to the other cases, the configuration (Mortar/Fired hollow clay brick and unfired solid clay brick/Mortar) demonstrated a 2 h improvement in time lag and a considerable decrease in the amplitude of the temperature fluctuation. Therefore, unfired solid clay bricks and fired hollow clay bricks may be used in combination to provide thermal comfort for a sustainable building. [ABSTRACT FROM AUTHOR]

This study presents a ground response assessment performed at Nador city (Morocco) and surrounding areas. We carried out the one-dimensional equivalent linear approach using the known geotechnical parameters to derive amplification analysis at studied sites, using the shear wave velocity (V S(30)) derived from boreholes. Seismic hazard assessment is performed using two gridded seismicity models and four ground motions attenuation equations, in order to address the epistemic uncertainty in a logic-tree framework. Seismic hazard maps depicting the mean estimated hazard values and including the uncertainty are presented in terms of spectral acceleration at 0.0, 0.1 and 0.2 s, with 10% and 5% probabilities of exceedance in 50 years, and for B, B/C and C soil conditions, as defined by the National Earthquake Hazards Reduction Program classification and for local site conditions as well. Typical values of Peak Ground Acceleration (PGA) equal to 0.18 g ± 0.03 and 0.26 g ± 0.05 are obtained at the Nador city for 475 and 975 return period respectively and for B/C soil conditions. The deaggregation analysis for both returns periods (475 and 975 years) in terms of magnitude-distance (named 2D deaggregation) and in azimuth (longitude and latitude named 3D deaggregation) allows us to derive the contribution of the different couple of magnitude-distance (M , D) and the different sources, the controlling earthquake are also determined at the five considered cities, for both return periods. From the site-specific seismic hazard analysis performed at five main cities located in the studied area, the seismic hazard curves and the uniform hazard spectra (UHS) are obtained with their uncertainties for the considered return periods and soil conditions, as well as the design spectra proposed by Malhotra (2005). Real accelerogram time-history is used to generate compatible acceleration time-history with the design spectra proposed by Malhotra (2005) and the EC-8 type 2 (Eurocode 8.2004), for both return periods and for B/C soil conditions. The lower root mean square error value (RMSE) is archived by using the Malhotra design spectra for the considered return periods. The results display a clear amplification in silty and clayey soils, greater than in silt-gravely soils, as well as no significant amplification in volcanic soils. Moreover, the resulting fundamental frequency is in the range of 1.4–2.8 Hz, and the maximum amplification factor observed in Nador is about 3.5. These values are consistent with the results derived from ambient noise, seismic records using HVSR technique and with the values given by Moroccan Seismic Code in the 2000 and 2011 regulations. • Amplification analysis is performed at Nador city and surrounding area, based on the one-dimensional equivalent linear approach using given geotechnical parameters. • We performed a probabilistic seismic hazard assessment for the region, in terms of peak ground acceleration (PGA) and spectral acceleration (SA) for different oscillation periods and for two return periods. • Response spectra analysis is carried out from the artificial acceleration, dynamics soil parameters and site amplification has been evaluated for each soil type. • The design spectra is carried out using the Malhotra procedure (Malhotra, 2005) and compared to the design spectra type II proposed by the EC 8. [ABSTRACT FROM AUTHOR]

Declining rainfall with increasing variability, increasing temperature extremes, and declining soil fertility are threatening crop production and ultimately food security in the rainfed Mediterranean environment in Morocco. Conservation agriculture (CA) practices such as reduced tillage, soil cover, and appropriate crop rotation are recognized as a set of adaptive agricultural systems in such climate-sensitive regions. Systematic evaluation of agronomic, economic, and soil fertility indicators with medium-and long-term adoption of CA in different crop rotations in such variable climatic conditions is needed to drive wider adoption of CA in the region. The objective of this study was to systematically evaluate agronomic, economic, and soil fertility indicators under CA and conventional tillage (CT) using field experimentation (medium-term) and simulation modeling (long-term) for a clay soil of a rainfed Mediterranean environment. Methodologies included the following: 1) Field experimentation for 5 years (2015–2019), comparing CA and CT in four major food crops: wheat, barley, lentil, and chickpea, conducted in Merchouch, Morocco. The objective was to determine the effect of CA on crop productivity, yield stability, profitability, precipitation use efficiency, and soil fertility indicators of individual crops and cropping systems. (2) Dynamic simulation modeling to understand the long-term effect of adopting CA and CT under cereal–legume and cereal–cereal rotation systems. Using 5 years of experimental data, we calibrated and validated a Decision Support System for Agrotechnology Transfer (DSSAT) model for four crops; and ran the model for 36 years for two major rotations. Across the five contrasting rainfall years, in comparison to CT, CA had greater yield stability and increased wheat grain yield by 43%, barley by 8%, lentil by 11%, and chickpea by 19%. In 5 years of cereal-legume rotation cycle, CA resulted in increased system yield (by 20%), total benefits (by 40%), precipitation use efficiency (by 13%), and available soil moisture (by14%) with production cost reduced by 14.5%. The CA system had higher soil organic matter (+7%), available phosphorus (+3%), and exchangeable potassium (+15%) than in CT, although all differences were non-significant. Our field experiment and long-term simulation results suggest that CA adoption improves a range of agronomic and economic, and soil fertility indicators compared to CT in the clay soil of a rainfed Mediterranean environment. The outcomes of this experimental and simulation study on the multiple benefits of CA provide evidence for extensionists, policymakers, and farmers to drive its wider adoption in Morocco and similar production environments. [Display omitted] • Rainfed Mediterranean region is facing higher rainfall and climatic variability • Conservation agriculture (CA) can close wheat, barley, lentil, and chickpea yield gaps • Experimental and long-term modeling approaches used to explore the impact of CA • CA improves yields, soil fertility and resilience than conventional in rainfed drylands • Cereal–legume rotation is more resilient than cereal monocrops under variable rainfall [ABSTRACT FROM AUTHOR]