The study combines three types of analyses. A palynological analysis reconstructs changes in the vegetation environment. A grain-size analysis of sediment particles, combined with End-Member Modeling, identifies sediment sources (fluvial versus aeolian transport). Finally, X-ray fluorescence (XRF) analysis, using the Fe/Ca intensity ratio, compares terrigenous inputs (Fe) to marine carbonate production (Ca), thereby reflecting environmental variations (erosion, river floods, dust inputs, etc.).

The results show that between 650 and 850 AD, the sedimentation rate increased significantly (rising from about 100 to 300 cm per 1,000 years), accompanied by a doubling of pollen flux and the Fe/Ca ratio. These converging signals indicate a substantial increase in terrestrial inputs to the marine environment and suggest a strengthening of erosion processes and fluvial transport to the ocean. At the same time, marked changes are observed in the pollen record: a sharp increase in Cichorioideae, Artemisia, and Plantago pollen—taxa indicative of open or anthropogenically disturbed environments—and a decline in deciduous oak pollen, while evergreen oaks show more limited variations.

These transformations are interpreted as resulting from intensified human pressures, consistent with socio-historical dynamics associated with the arrival and spread of Islam from the 7th century onward, a period marked by the expansion of human settlement, agriculture, and pastoralism in the region. The increase in agropastoral activities, particularly goat herding, likely promoted the degradation of woody vegetation and intensified erosional processes.

After 850 AD and up to the present, sedimentary indicators (sedimentation rate, Fe/Ca) remain relatively stable, suggesting lower variability in terrigenous inputs. In contrast, pollen assemblages continue to indicate degradation of natural vegetation, including signs of expansion of tree crops (olive, argan) and the introduction of exotic species such as eucalyptus over the past 150 years.

Overall, the results highlight the significant impact of socio-economic dynamics on vegetation and regional erosion, as recorded in marine sediment archives.

McGregor H.V., Dupont L., Stuut J.-B. W & Kuhlmann H., 2009 - Vegetation change, goats, and religion: a 2000-year history of land use in southern Morocco. Quaternary Science Reviews 28, 1434–1448.

However, the direct transfer of this framework to the North African context encounters major biogeographical and ecological limitations. The present typology therefore undertakes a reasoned adaptation of the EUNIS framework, based on consideration of Morocco’s climatic, geomorphological, and phytogeographical specificities. In particular, it incorporates arid and Saharan habitats that have no strict equivalents in the European reference system (argan woodlands, arid and Saharan steppes, formations dominated by thuya, Acacia spp. or Euphorbia spp., oases, chotts and desert sebkhas). It also takes into account structuring geomorphological units (graras, regs, ergs, wadi beds), as well as the major vegetation units described for Morocco by Ionesco and Sauvage (1962), whose physiognomic and ecological significance remains decisive in landscape organization.

The typology is based on a nested hierarchical structure. The first level corresponds to major environment types (Level 1, referred to as the highest level of description). Each Level 1 unit is subdivided into Level 2 units, which are themselves divided into Level 3 units. This graduated structuring progressively increases the degree of descriptive precision and refines the ecological characterization of habitats.

Within the scope of the present essay, the hierarchy does not extend beyond the third level. At lower levels, discriminating criteria become more specialized and draw upon conceptual frameworks that do not always benefit from scientific consensus. In particular, the definition of finer units could rely on a phytosociological approach. Although this approach provides a rigorous theoretical basis, its application often remains challenging in operational contexts, due to its technical complexity and its relative difficulty of appropriation by a broader audience of stakeholders, particularly managers and field practitioners. At this stage, the authors have therefore favored a consultative approach, leaving open the possibility of further refinement based on feedback and the input of managers.

The classification distinguishes 11 major environment types, whose degree of resolution varies according to the state of available knowledge and existing literature. It builds upon the Moroccan phytosociological tradition while adopting a structure compatible with international standards. In its current form, this proposal constitutes an operational reference framework for the identification and mapping of Morocco’s continental habitats. It demonstrates satisfactory internal coherence and defensible conceptual robustness, and provides a methodological foundation capable of evolving toward finer levels of precision as knowledge advances and scientific consensus is consolidated.

Réf. Sghir Taleb M. & Fennane M., 2025 - Essai de classification des habitats continentaux du Maroc (niveaux hiérarchiques supérieurs et moyens). Université Mohammed V de Rabat, travaux de l’Institut Scientifique, série Générale, n° 10, 122 p.

In this study, the researchers carried out a comprehensive analysis of the argan tree genome to identify and characterize genes encoding SODs. In total, nine SOD genes were identified and classified into three groups according to the metal cofactor involved. This classification was confirmed through analyses of their gene structures, evolutionarily conserved protein sequences essential for enzymatic function, as well as phylogenetic relationships with SODs from other plant species. In addition, analysis of the regulatory regions of these genes revealed the presence of several cis-regulatory elements associated with stress responses, suggesting a potential role of SOD genes in the adaptation of the argan tree to unfavorable environmental conditions.

Finally, 36 pairs of specific primers were designed to facilitate the analysis of gene expression in future experiments. Their efficiency and specificity were evaluated through in silico analyses, indicating satisfactory performance for subsequent applications.

Overall, this study provides a solid foundation for a better understanding of the role of SOD genes in the argan tree. These findings could ultimately contribute to the development of more stress-tolerant plants capable of better withstanding drought, salinity, and other environmental constraints.

Ref. Chahidi M., El Faqer A., Rabeh K. & Belkadi B., 2025 - Genome-wide survey of superoxide dismutase (SOD) genes in Argania spinosa L., an endemic tree species. Discover Plants (2025) 2:362 – https://doi.org/10.1007/s44372-025-00379-x

The seeds used originated from two distinct sites: Aoulouz, located to the west at the bottom of the Souss plain at the foothills of the High Atlas Mountains (altitude: 700–850 m; average annual rainfall of approximately 232 mm; mean minimum and maximum temperatures of 5.6 °C and 35.7 °C, respectively), and Lakhssas, situated to the south in the Guelmim region (altitude: 916–988 m; annual rainfall of approximately 189 mm; mean minimum and maximum temperatures of 7.3 °C and 31.2 °C, respectively).

The experiment involved twelve one-year-old plants grown in 15 × 15 cm pots containing a substrate composed of a 4:1 mixture of forest soil and peat, and evenly distributed between the two ecotypes and the two experimental conditions (water stress and control). Metabolite identification was carried out using an analytical technique combining gas chromatography and mass spectrometry (GC–MS).

Under water stress conditions, statistical analysis (t-test, p < 0.05) identified 44 metabolites significantly affected in the Lakhssas ecotype and 56 in the Aoulouz ecotype.

A volcano plot was then used to distinguish overexpressed and underexpressed metabolites under water stress. In this graph, the log₂ fold change (log₂FC), representing the relative variation in metabolite abundance between water-stressed and control conditions, is plotted on the x-axis, while the y-axis (−log₁₀(p)) indicates statistical significance. Metabolites located on the right side of the graph (positive log₂FC) correspond to overexpressed metabolites (significantly higher concentration under water stress compared to the control), whereas those on the left (negative log₂FC) are underexpressed (significantly decreased concentration under water stress compared to the control). Accordingly, 34 metabolites were overexpressed and 10 underexpressed in Lakhssas, while in Aoulouz, 25 metabolites were overexpressed and 31 were underexpressed.

The relative importance of each metabolite was assessed using Variable Importance in Projection (VIP) analysis, which allows identification, within a multivariate model, of compounds contributing most to the discrimination between the two ecotypes. Based on this analysis, twenty metabolites with a VIP score ≥ 1, indicating a significant contribution, were selected.

Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) revealed a clear separation between control samples and those subjected to water stress. Based on the importance of variables in projection scores as well as receiver operating characteristic (ROC) curve analyses, ten potential biomarkers of drought tolerance were identified.

In the Aoulouz ecotype, two overexpressed metabolites, M65 (lupeol) and M102 (octadecane), as well as three underexpressed metabolites, M108 (octacosane), M123 (5-octadecene, E), and M200 (diethyl ester of 4-nitrobenzylidenemalonic acid), were found to be determinant. In contrast, the Lakhssas ecotype exhibited five overexpressed biomarkers: M6 (methyl hexadecanoate), M54 (1,3,6,10-cyclotetradecatetraene, 3,7,11-trimethyl-14-(1-methylethyl)), M88, M91, and M142.

Metabolites M65 and M102 in Aoulouz likely contribute to strengthening cuticular integrity and mitigating oxidative stress responses. Conversely, the overexpression of M6 and M54 in Lakhssas suggests an adaptation strategy relying more heavily on lipid signaling and energy metabolism. However, this ecotype may prove less resilient to prolonged drought due to a greater capacity for metabolic reallocation.

In conclusion, the study demonstrates that the two ecotypes adopt distinct strategies: the Aoulouz ecotype develops durable tolerance through reinforcement of the cuticle and improved management of oxidative stress, while the Lakhssas ecotype relies on transient metabolic adjustments. These findings are valuable as they link measurable metabolic signatures to effective physiological strategies, paving the way for practical applications in plant breeding and sustainable agriculture under water stress conditions.

Réf. Rabeh K., Farid Rachidi F., Sbabou L. et al.,2025 - Potential metabolite biomarkers of drought tolerance in contrasting Sideroxylon spinosum L. ecotypes using a metabolomic approach. J. Sci. Food Agric. (wileyonlinelibrary.com) DOI 10.1002/jsfa.70365

More specifically, the analysis focuses on the entire body of scientific literature related to argan oil—whether its nutritional, cosmetic, or medicinal uses—as well as on the biology, ecology, and conservation issues surrounding the argan tree. It also covers the applications of remote sensing for mapping and monitoring the spatio-temporal dynamics of argan woodlands. The ultimate goal is to highlight existing sustainable management practices and identify the main challenges ahead.

The quantitative analysis of scientific output was carried out using the Bibliometrix software package and its Biblioshiny interface, powerful tools based on the R language that enable the examination of a research field’s structure, evolution, and dynamics through advanced network analysis and visualization methods. The construction and representation of networks (keyword co-occurrence, author collaboration, co-citations, citations) were performed with the VOSviewer software.

The first stage of the analysis focused on the scientific literature devoted to argan oil. Between 1992 and May 2024, six hundred contributions were recorded. Examination of the co-occurrence of the 2,678 keywords from this corpus reveals three thematic clusters that are strongly interconnected.

The first group (16 items) concerns the effects of argan oil on health and includes notions such as “phenolic compounds” and “oxidative stress.” The second group (also 16 items) relates to the assessment of oil quality and its health implications, featuring keywords such as “adulteration” and “tocopherol.” The third group (11 items) refers to the botanical characteristics of the argan tree and its ecological role in Morocco.

The analysis of six hundred publications highlights a marked increase in scientific output starting in 2009, as well as the diversity of contributors, research hubs, and collaboration networks. Unsurprisingly, Morocco—where the argan tree is an endemic species—holds the leading position in this field. Moroccan institutions also maintain numerous partnerships with French and German establishments.

The second phase of the analysis focuses on studies dedicated to the ecology and physiology of the argan tree. Between 1992 and 2024, three hundred and ninety contributions were recorded. Examination of the co-occurrence network of the 134 most frequently used keywords in this literature reveals seven major research themes: the biochemical, molecular, and biological properties of argan compounds; ecological, physiological, and conservation-related dimensions; ecology, management, and uses; physiological responses to abiotic stress; growth and development; genetics, ecology, and evolutionary biology; as well as environmental processes and management strategies.

In recent years, the integration of advanced remote-sensing and machine-learning techniques, relying on multi-source satellite imagery, has significantly improved the mapping and monitoring of argan woodlands, thereby contributing to the conservation and sustainable management of this forest ecosystem.

Réf. El Moussaoui EH., Moumni A., Khabba S. et al., 2025 Bibliometric and review analysis of argan trees studies: global research trends and challenges. Agroforest Syst, 99:132 https://doi.org/10.1007/s10457-025-01228-2

Réf. Homrani Bakali A. & Khamar H., 2025 New records and floristic notes on the genus Oenothera (Onagraceae) in Morocco. – Botanica, 31(4): 142–154. https://doi.org/10.35513/Botlit.2025.4.1

The results derived from the three datasets are fully congruent: the four analyzed populations of Nepeta nepetoides form a well-supported, distinct clade that is sister to other members of the subtribe Menthinae, rather than to those of the Nepetinae. Consequently, this species should no longer be retained within the genus Nepeta but must be transferred to the genus Pitardia.

Pitardia can be distinguished from Nepeta by several diagnostic morphological traits: the presence of two stamens and the absence of staminodes (four stamens in Nepeta), a calyx tube with 10 veins (typically 15 [13–17] in Nepeta), and a convex, entire median lobe of the lower corolla lip (usually crenate in Nepeta).

Ref. Homrani Bakali A., Dirmenci T., Celep F. & Drew B.T., 2025 - Pitardia resurrected: A new member of subtribe Menthinae (Lamiaceae). Taxon, https://doi.org/10.1002/tax.70053

Molecular data suggest that the divergence between E. balsamifera and E. adenensis occurred during the Pliocene, a period spanning approximately 5.3 to 2.6 million years ago. This era coincides with a major episode of climate aridification in the subtropical regions of the Old World, leading to the fragmentation of forest habitats in favor of more open and arid landscapes. These new environmental conditions likely facilitated a rapid adaptive radiation of the ancestral group, meaning the emergence of several lineages specialized for arid habitats.

In this context, E. balsamifera is thought to have colonized the Canary Islands from northwestern Africa. This colonization may be explained by the "surfing syngameon" mechanism—an evolutionary hypothesis in which a flexible gene pool (or syngameon) "surfs" waves of dispersal into new territories while maintaining sufficient genetic diversity to allow rapid adaptation to novel environments.

Computer models using convolutional neural networks (a form of artificial intelligence) suggest that E. balsamifera first settled on the eastern islands (Lanzarote, Fuerteventura), before migrating westward (Tenerife, Gran Canaria).

Contrary to what one might assume, the populations in North Africa are not remnants of an ancestral continental population. Instead, they result from migratory events originating from the islands of Lanzarote and Fuerteventura. These back-colonization events likely occurred during the Middle Pleistocene, although this still requires confirmation.

This finding challenges the notion that islands merely "receive" genetic diversity from the continent. In this case, the Canary Islands actually generated new genetic diversity that subsequently spread back to the African mainland.

Ref. : Rincón-Barrado M., Villaverde T., Perez M.F., Sanmartín I. & Riina R., 2024 - The sweet tabaiba or there and back again: phylogeographical history of the Macaronesian Euphorbia balsamifera. Annals of Botany 133 : 883–903. https://doi.org/10.1093/aob/mcae001, available online at www.academic.oup.com/aob

The literature search was conducted using the same keywords in the Scopus and Web of Science databases, selecting publications in English and French published between 2000 and 2024. Using the PRISMA method, 55 articles were selected, the majority of which (36) originate from Morocco, the native country of the argan tree.

The bibliometric analysis, performed using the VOSviewer software, enabled the visualization of links between the main keywords related to argan tree research. This map highlights the central position of germination, around which micropropagation, seed sowing, in vitro culture, and vegetative propagation are organized.

The discussion compares the different techniques: seed germination, which has a low success rate, is contrasted with the advantages of cutting and grafting, which allow for rapid rooting and greater genetic stability. In vitro micropropagation also appears to be a promising method, although it requires strict acclimatization conditions.

In conclusion, the study emphasizes the importance of combining traditional methods with modern biotechnological approaches to ensure the reproduction and sustainable conservation of this emblematic species.

Ref. : Tesse R., Boutaleb F., Bahlaouan B., Brett-Crowther M., El Antri S., & Boutaleb N., 2025 - Micrografting and Other Regeneration Techniques for the Argan Tree (Argania spinosa): A PRISMA-Based Systematic Review and Meta-Analysis. Natural Built Social Environment Health 1(3). DOI :10.63095/NBSEH.25.180342

Ref. : Homrani Bakali H., Chatelain C. & Khamar H., 2025 - New non-native species recorded in cumin crop in southeastern region of Morocco. Botany Letters, DOI : 10.1080/23818107.2025.2506559 (18 Jun).