Essaouira Region Research Articles

Combined Effect of Subsurface Water Retention Technology and Arbuscular Mycorrhizal Fungi on Growth, Physiology and Biochemistry of Argan Seedlings under Field Conditions.

The argan (Argania spinosa L. Skeels) ecosystem is severely degrading in arid and semi-arid lands due to climate change, particularly in terms of density loss and reforestation failure. Thus, it is important to adopt innovative effective sustainable practices to optimize the densification and reforestation success of the argan tree. The purpose of the present research was to investigate the combined effect of subsurface water retention technology (SWRT) and the use of native arbuscular mycorrhizal fungi (AMF) on edaphic, growth, physiological and biochemical parameters of field-grown argan seedlings in the Essaouira region, Morocco. In this experiment, one-year-old argan seedlings were transplanted in the absence and presence of biodegradable plastic and AMF. Our findings revealed that the application of SWRT enhanced soil profile moisture up to 640% at 40 cm depth compared to the control. The combination of this technology with AMF also improved soil fertility. Furthermore, the application of SWRT, with or without AMF, significantly enhanced argan seedling height (208 and 168%, respectively), stomatal conductance (54 and 33%, respectively), and chlorophyll fluorescence (21 and 20%, respectively). Similarly, the combined application of SWRT and AMF significantly improved protein and sugar content (36 and 57%, respectively), as well as antioxidant enzyme activities (peroxidase and polyphenol oxidase) and chlorophyll pigments content compared to the control. However, this treatment reduced malondialdehyde and H2O2 content in the argan leaves. As a summary, SWRT technology combined with AMF may be used as a valuable strategy to promote the success of argan reforestation and to limit soil erosion and desertification in arid and semi-arid climates.

Assessing the influence of different Synthetic Aperture Radar parameters and Digital Elevation Model layers combined with optical data on the identification of argan forest in Essaouira region, Morocco

Assessing the influence of different Synthetic Aperture Radar parameters and Digital Elevation Model layers combined with optical data on the identification of argan forest in Essaouira region, Morocco

Examining the methods used to extract various grades of Argan oil sold on the Moroccan market: Implications for quality and safety

The present study focused on the comparison of Argan oil extraction processes and their influence on oil and cake quality and safety. A survey was conducted among Argan oil producers in the Essaouira region of Morocco. The responses revealed that the quality of Argan products is influenced by several factors, the main one being the quality of the fruit. For 25% of responses, representing the women selling Argan oil in the souks, Argan fruits “AQAY” are soaking in water to facilitate the crushing stage. However, this maceration can lead to fermentation and mold. Besides, the quality of the mixing water is different from one response to another. Just 50% of responses came from cooperatives use high microbiological quality water. Eventually, poor-quality water affects the composition and shelf life of Argan products besides consumer health and safety. Furthermore, there is also significant variation in roasting time and temperature, roaster type, and storage conditions. Indeed, these factors have the greatest influence on the quality of Argan products. Consequently, the present investigation has shown that the extraction process from raw material to final product varies considerably between the obtained results. Therefore, extraction processes and storage conditions need to be standardized. This will improve the quality of Argan oil and cake.

The Study of the Heterogeneity of the Qualities of Argan Oils and Pomaces from Different Cooperatives in the Essaouira Region (Morocco)

In this study, a comparison of the intra-regional variation in the quality of Argan oil and pomace collected from 12 cooperatives in the Essaouira region (Morocco) during the COVID-19 period was carried out. All studied Argan pomaces together with the extraction solvents showed a significant difference (p ≤ 0.05) in the total phenolic compounds, flavonoids, and tannins contents. The proteins, residual oils, total sugars, and total reducing sugars contents in the collected pomaces vary considerably among cooperatives of origin, with maximum averages of 50.45%; 30.05%; 3.82 milligrams of glucose equivalent per gram of dry matter; and 0.53 milligrams of glucose equivalent per gram of dry matter, respectively. Therefore, it is a very valuable ingredient for livestock feed and some cosmetic products that may contain it. The remaining Argan oil content in the pomace varied significantly among cooperatives, ranging from 8.74 to 30.05%. Pomace from traditional extraction recorded the highest content (30.05%), showing that the artisanal and modern extraction processes are not standardized. The measurements of acidity, peroxide value, specific extinction coefficient at 232 nm and 270 nm, and conjugated dienes were carried out in accordance with Moroccan Standard 08.5.090 in order to qualitatively classify all investigated Argan oils. Accordingly, the analyzed oils were categorized as "extra virgin Argan oil," "fine virgin Argan oil," "ordinary virgin Argan oil," and "lampante virgin Argan oil." Therefore, several factors can explain these variations in quality grades, both endogenous and exogenous. Overall, the variation observed in the obtained result allows us to deduce the most significant variables impacting the quality of Argan products and by-products.

THE INFLUENCE OF THE FORMS ON THE QUALITY, CHEMICAL COMPOSITION AND ANTIOXIDANT ACTIVITY OF ARGAN OIL GROWN IN MOROCCO

Argan oil plays a significant socio-economic role in southwestern Morocco, with many applications in cosmetics and nutrition. In this study, the chemical composition, the quality, as well as antioxidant activity of Argan oils extracted from different fruit shapes (apiculate, oval, spherical, and fusiform) in Essaouira and Agadir were evaluated. The results collected indicated a slight resemblance in the chemical composition of fatty acids, sterols, tocopherols, and polyphenols of Argan oils. These, extracted from two different regions, also show similar yields in the oval form, with values of 53.53 % for the Essaouira region and 54.86 % for that of Agadir. However, a slight difference was noted in the shape of the fruit. Indeed, the total sterols content for the oval shape showed values of 178.64 mg/100g in the Essaouira region and 171.97 mg/100g in the Agadir region. Also, γ-tocopherol was the predominant tocopherol in all tested oils.

Geochemical and isotopic evidence of groundwater salinization processes in the Essaouira region, north-west coast, Morocco

The city of Essaouira is located along the north-west coast of Morocco, where groundwater is the main source of drinking, domestic and agricultural water. In recent decades, the salinity of groundwater has increased, which is why geochemical techniques and environmental isotopes have been used to determine the main sources of groundwater recharge and salinization. The hydrochemical study shows that for the years 1995, 2007, 2016 and 2019, the chemical composition of groundwater in the study area consists of HCO3–Ca–Mg, Cl–Ca–Mg, SO4–Ca and Cl–Na chemical facies. The results show that from 1995 to 2019, electrical conductivity increased and that could be explained by a decrease in annual rainfall in relation to climate change and water–rock interaction processes. Geochemical and environmental isotope data show that the main geochemical mechanisms controlling the hydrochemical evolution of groundwater in the Cenomanian–Turonian aquifer are the water–rock interaction and the cation exchange process. The diagram of δ2H = 8 * δ18O + 10 shows that the isotopic contents are close or above to the Global Meteoric Water Line, which suggests that the aquifer is recharged by precipitation of Atlantic origin. In conclusion, groundwater withdrawal should be well controlled to prevent groundwater salinization and further intrusion of seawater due to the lack of annual groundwater recharge in the Essaouira region.

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

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.

An assessment of the changes in the behavior of the groundwater resources in arid environment with global warming in Morocco

This study aims to assess the effect of climate change on water resources in semi-arid environments, taking the Essaouira region in Morocco as an example. Analysis of climate data shows a decrease in precipitation of 12–16% and an increase in air temperature of 2.3 °C over the past three decades. A continuous drop in the piezometric level of more than 12 m for the Cenomanian-Turonian aquifer, 17 m for the Plio-Quaternary aquifer, around 8 m for the Barremian-Aptian aquifer and 5 m for the Hauterivian. Hydrogeochemical analysis together show that (i) the groundwater mineralization is controlled by the dissolution of evaporitic and carbonates minerals, by the reverse ions exchange phenomenon, and by sea water intrusion, especially at Plio-Quaternary aquifer; and (ii) the groundwater quality in the study area deteriorates gradually over time and space. The isotopic data shows that (i) the groundwater recharge in the study area is ensured by precipitation of oceanic origin without significant evaporation and that (ii) climate change has no remarkable effect on the isotopic content of the groundwater of the study area. However, the results of this article reflect that the Essaouira basin is very vulnerable to climate change.

Absence of Hemolivia mauritanica (Apicomplexa: Haemogregarinidae) in natural populations of Testudo graeca in Morocco.

During spring 2018, we captured 101 spur-thighed tortoises, Testudo graeca, from seven localities in central Morocco. All tortoises were examined for the presence of blood parasites Hemolivia mauritanica and Hyalomma aegyptium ticks, the known vectors. We looked for H. mauritanica infection by examination of blood smears and by genetic analysis with PCR using extractions from both tortoises and ticks. On all tortoises collected, 71.29% were infested with at least one tick, with a mean infestation intensity of 7.12 ticks/tortoise and maximum of 15.55 ticks/tortoises in Had Draa locality (Essaouira region). Although the definitive host is present and abundant in all tortoise populations, all blood samples were Hemolivia-negative. Our results support and confirm the finding of studies previously conducted in other populations of Morocco and indicate that H. mauritanica has a narrower distribution range than its tick vector.

Global warming and groundwater from semi-arid areas: Essaouira region (Morocco) as an example

Climate change is undoubtedly becoming a subject of great concern for public authorities in all regions of the globe, in particular, the regions under Saharan, arid, and semi-arid climate. In this regard, this study aims to assess the effect of climate change on groundwater from semi-arid environments, taking the Essaouira basin as an example. The climate approach shows a downward trend in precipitation from 12 to 16% and an increase in temperature from 1.2 to 2.3 °C, and this during the last three decades. A continuous decline in the piezometric level exceeding 12 m for the Cenomanian–Turonian aquifer and 17 m for the Plio-Quaternary aquifer has been observed. The groundwater mineralization is controlled by the dissolution of evaporate and carbonate minerals, by the bases exchange phenomenon, and by the marine intrusion, especially in Plio-Quaternary aquifer. Also, the groundwater quality in the study area deteriorates gradually over time and space. However, the results of this study confirm that the groundwater from Essaouira basin is vulnerable to the global warming.

Climate change effect on groundwater characteristics within semi-arid zones from western Morocco

The purpose of this study is to evaluate quantitatively and qualitatively the groundwater from semi-arid environment in the context of climate change by taking the Barremian-Aptian and Hauterivian aquifers of Essaouira basin (Morocco) as an example. For a period of 43 years (1976–2019), the piezometric level shows a continuous decline which reaches 8 m for the Barremian-Aptian aquifer and 5 m for the Hauterivian. Hydrogeochemical analysis shows (i) a remarkable evolution of the facies from the Cl–Na facies to the Cl–Ca–Mg facies, (ii) the groundwater mineralization is governed by the dissolution and bases exchange phenomenon, (iii) the spatial-temporal evolution of the groundwater quality shows a gradual deterioration in time and space. The isotopic technique shows that the groundwater recharge is ensured by precipitation of oceanic origin without notable evaporation. Tritium tracing shows that the recharge of groundwater is post-nuclear, confirming that the recharge of the aquifers within the study area is in close relation to the precipitation. This recharge takes place at altitudes varying between 500 and 700 m asl for the Barremian-Aptian aquifer and between altitudes 350 and 400 m asl for the Hauterivian aquifer.However, the results obtained indicate that the water resource of Essaouira region is very vulnerable to global warming and requires adequate intervention of decision-makers in terms of management, protection and planning.

A case of massive infestation of a female Spur-thighed tortoise Testudo graeca by blood-sucking ticks Hyalomma aegyptium (Acari: Ixodidae)

ABSTRACTInfestation by ticks affects several vertebrate groups, including tortoises. Testudo species are among chelonian fauna that are infested in their natural habitat by several tick species, with Hyalomma aegyptium as the dominant one. We report a heavy tick infestation found in female T. graeca in May 2018 in Had Draa (Essaouira region, Morocco). The female, with carapace length of 175 mm and body weight of 779.3 g was found to be infested by 288 H. aegyptium in different stages. It was more infested by female ticks than males, and the hind limbs (59.6%) and forelimbs (30.25%) were the most frequent predilection sites of ticks. Our data provide the first record of massive parasitism by H. aegyptium in this vulnerable and threatened tortoise.

Contributions of indigenous arbuscular mycorrhizal fungi to growth of retama monosperma and acacia gummifera under water stress (case study: essaouira sand dunes forest)

ABSTRACTTwo leguminous plant species: Retama monosperma and Acacia gummifera were selected for water deficit tolerance test for future use in reforestation programs of the Atlantic sand dunes forest of Essaouira region. Mycorrhizal fungal colonization was used to help plants amend the water deficit. To assess R. monosperma and A. gummifera response to water stress and the effectiveness of mycorrhizal formation alleviating it, two categories for each plant species were made, one inoculated with mycorrhizal fungi and the other not, were submitted to a hydric deficit treatment of four levels for 6 months. This treatment impact on the plants was assessed by comparing root/shoot dry weight ratios, levels of nitrogen and phosphorus, and by measuring mycorrhizal colonization frequencies and intensities. Results showed that these parameters were significantly affected by water deficit. The presence of the mycorrhizal fungi had significantly enhanced plants phosphorus uptake by 72–124% for Acacia gummifera and 87–161% for Retama monosperma. Nitrogen uptake was increased by 134–388% for Retama monosperma and 510–901% for Acacia gummifera. The colonization frequencies changed significantly only for the treatment extreme level and stayed between 80%-90% for the other levels. The mycorrhization intensities showed significant lessening between each treatment level decreasing from 35% to 10%.

Analysis of symbiotic microbial status of Atlantic sand dunes forest and its effects on Acacia gummifera and Retama monosperma (Fabaceae) to be used in reforestation

Atlantic forest natural soil flora was tested on two leguminous pioneer species Acacia gummifera and Retama monosperma to be used in rehabilitation programs of the coastal sand dunes forest of the Essaouira region. The rhizospheric soil of two endemic plant species: R. monosperma and Juniperus phoenicea was sampled and split into two categories, one from native rhizospheric soil, the other of the sterilized rhizospheric soil. Investigation was focused on mycorrhizal formations, but other forms of beneficial symbiosis such as rhizobia and viable soil microflora were also studied. Growth and nutrition variables assessed included lengths of roots and shoots, number of branches, ratio of root to shoot dry mass and water, nitrogen and phosphorus levels. Results showed important mycorrhizal associations in roots of both plants, presence of nodules and abundance of viable soil microflora. J. phoenicea had a 100% frequency of mycorrhizal formation and an intensity of 80% compared to a frequency of 80% and intensity of 54% for R. monosperma. Nodules had the same density of CFU regardless of the origin. Abundance of viable microflora in rhisospheric soil of R. monosperma, J. phoenicea and the control differed significantly. Among the studied variables for A. gummifera and R. monosperma, nitrogen and phosphorus uptakes significantly wit the use of the nonsterilized rhizospheric soil. Both species doubled their phosphorus uptake when colonized by mycorrhizal species, R. monosperma doubled its nitrogen uptake and A. gummifera increased it by seven times compared with the control. No significant difference was noted for the other variables.

Hydrogeochemical investigation and groundwater quality in Essaouira region, Morocco

Given the scarcity, or even absence, of surface water and the domination of the semi-arid climate in the coastal zone of the Essaouira basin (Morocco), the Plio-Quaternary, Turonian, Barremian–Aptian and Hauterivian aquifers represent the main source of water for fine consumption and agriculture. However, the study of their quality is a priority. So as to reach the objective of this study, the combination of the two hydrogeochemical and geographical information system tools was used. The results obtained showed that the facies characterising the Plio-Quaternary aquifer was a combination of Ca–Mg–Cl and Na–Cl, and that characterising the Turonian, Barremian–Aptian and the Hauterivian aquifer was a combination of Ca–Mg–Cl. However, flagship ions in the study area are Cl, Na, Ca and Mg. For consumptions purpose, the comparison of the concentrations of major elements with the standards of the World Health Organization showed that all the elements presented concentrations below the threshold, except for chlorides, the concentrations of which exceeded the threshold. For the agricultural purposes, the two Wilcox and United States Salinity Laboratory (USSL) diagrams, and the spatial distribution of parameters total dissolved solids, total hardness, permeability Kelly’s ratio, sodium hazard, sodium percentage and nitrates showed that the groundwater in the study area is adequate for persistent plants with a high to very high salinity tolerance.

Comparative analysis of some biochemical parameters of argan pulp morphotypes (Argania spinosa (L) Skeels) during maturity and according to the continentality in Essaouira region (Morocco).

Argania spinosa (L.) Skeels is an endemic forest tree for Morocco. The phytochemical compounds evaluation of four different morphotypes of their fruit pulps was investigated. The total content of sugar, protein and phenolic compounds were monitored during three different stages of maturation in the semi-continental (Mejji) and littoral regions (R'zwa). Total sugars, proteins, phenolics increased up to the ripe stage of all argan fruit morphotypes in the two regions. Spherical shape had higher sugar and protein content than other morphotypes. A significant difference (p<0.05), was demonstrated by Pearson's test, between the different morphotypes at three stages studied for all the phytochemicals compounds. Likewise, ANOVA test established that the variation of this compounds was influenced by the stage of maturation and/or region of development and/or their interaction according to fruit shape. Results from this study revealed that the increase of these parameters level take place for the most part during the last stages of maturity which synchronize with fruit softening. Furthermore, our results showed information about the richness of argan fruit pulp in carbohydrates compounds and secondary metabolites as the possibility of their contribution in nutritive forage value especially at ripe stage.

The last occurrence of Megaceroides algericus Lyddekker, 1890 (Mammalia, Cervidae) during the middle Holocene in the cave of Bizmoune (Morocco, Essaouira region)

During the course of archaeological test excavations carried out in 2007 in the cave of Bizmoune (Essaouira region, Morocco), seven archaeological layers yielding Pleistocene and Holocene artefacts and faunal remains were identified. In the layers C4, C3 and C2, respectively from the oldest to the most recent, terrestrial Helicidae mollusk shells (Helix aspersa) were dated by 14C. These layers also contained many fragments of eggshell, belonging to Struthio cf. camelus, associated with mammal remains such as Oryctolagus/Lepus, Gazella sp., Sus scrofa, Ammotragus lervia, Alcelaphus buselaphus, Equus sp., Phacochoerus aethiopicus and an undetermined Caprini. Among these remains, an incomplete mandible of Megaceroides algericus Lydekker, 1890 with M1 and M2 was found in layer C3. The 6641 to 6009 cal BP time range attributed to this layer has provided the most recent date known so far for M. algericus. In this study, we review and contextualize the findings of this particular species both in time and space and discuss its systematic position. We describe the morphology of the typical pachyostosic mandibular bone with the teeth and compare the dimensions with existing data. The assumption of the combined development, on the one hand, of the pachyostosic phenomenon and on the other hand, of the body weight fluctuations and growth of antlers for cervids strongly affected by seasonality is not supported. In order to understand the origin and the extinction of M. algericus, we examined the AMS radiocarbon dates available in the literature and calibrated them with RenDateModel software. Comparisons are then made with sea surface temperatures (e.g. GISP2 δ18O), eustasy and related environmental changes throughout the time span of this species. Based on these data a possible migration route by the Strait of Gibraltar connected with with eustatic rises in sea-level rises are discussed. The speciation-extinction processes for M. algericus and their correlations with climatic shifts on a long time-scale in North Africa (e.g. Heinrich events, 8200 cal BP event) are also considered. Finally, this new discovery in Bizmoune cave clearly shows that M. algericus lasted until the very end of the Epipaleolithic, around 6000 cal BP (middle Holocene), whereas this species was formerly not believed to have survived until the early Epipaleolithic (around 8000 cal BP).

Simulation of PV–Wind-hybrid systems combined with hydrogen storage for rural electrification

Since many years, engineering, research and development of hybrid systems for rural electrification are strongly supported by computer simulations. Different software packages have been used according to the required level of details along with the progress of the project HYRESS. For the development of optimal system control and load/energy management strategy, different simulation models from APL (Alternative Power Library) have been used for a Hybrid PV–wind-hydrogen system that will be installed in the Essaouira region in Morocco. This library provides models developed by IWES for the simulation of regenerative power supply systems and it is used to investigate the integration of a hydrogen storage path in hybrid system operation.

Shrewd shrikes and spiny shrubs: a calamity for hatchling Moorish tortoises (Testudo graeca graeca)

Cheloniansliveinasafe-boxthatoffersanef-Þcientprotectionagainstmostpredators,atleastin adults and sub-adults (Wilbur and Morin,1988). Nevertheless, in hatchlings, and to alesser extent, in juveniles the shell is soft and/ornot solid enough to resist to many predatorssuch as monitors, dogs, or birds for example(DouglasandWinegarner,1977;FitzpatrickandWoolfenden, 1978; Branch and Els, 1990; Gef-fen and Mendelssohn, 1997; Keller et al., 1998;Hill, 1999; Lagarde et al., 2001; Boarman,2002). In an open landscape, the predation onthese fragile tortoises can be severe; sometimesleaving strong marks on the population dynam-ics (Boarman, 2002). In April 2003, during aÞeld study on the ecology of Testudo graecagraeca in Morocco (Essaouira region, 31 23 N,9 42 W), we found several hatchling tortoisesimpaled on spiny shrubs ( Argania spinosa )ina typical shrike manner (Cramps and Perrins,1993). Therefore, several observations of shrike(Lanius excubitor ) were made in the study areaand even on the involved shrubs. We searchedintensively the study site and the surroundingarea (the total prospected area was 50 ha) anddiscovered a total of 25 impaled tortoises in 3spiny shrubs (respectively 17, 7 and 1 tortoisespershrub).WithanaverageShriketerritorysizeof 75 ha (Cramps and Perrins, 1993), such pre-dation may be due only to one Shrike breed-

Transtensive synsedimentary tectonics associated with ocean opening: the Essaouira–Agadir segment of the Moroccan Atlantic margin

The Mesozoic–Cenozoic sedimentary sequences of the Agadir–Essaouira region were studied by field observations in the onshore basin and offshore by seismic profiles and borehole data. During the Late Jurassic and the Early Cretaceous, they were frequently disturbed by repeated synsedimentary tectonic instability, extensively demonstrated by structures such as slumps, breccias, faults, etc. Regionally, these movements led to the initiation of ridges, in some cases diapiric, as well as depocentres. These are mainly N 70°E to E–W trending. Contemporaneously with a slight tectonic inversion of some of the offshore half grabens, the Late Jurassic–Cretaceous regional deformation converted the synsedimentary ridges to anticlines, and the depocentres to synclines, before the latest ‘Atlasic’ orogenic uplift, during the Cenozoic. This structural evolution distinguishes the Agadir–Essaouira segment from other parts of the Atlantic margin of Morocco. It results from an interference between the N20°E-oriented passive margin of Morocco and the N70°E-oriented Atlasic zone. The latter acted as a transform zone during Late Jurassic–Early Cretaceous times and then suffered a N–S compression during the Atlasic orogeny.