A Contribution to the Knowledge of Vascular Flora of the Site of Biological and Ecological Interest of Kharouba in the Central Plateau of Morocco

The current study aims to quantify and evaluate the Tetraclinis stands (Tetraclinis articulata (Vahl.) Masters) richness and floristic diversity at Kharouba Site of Biological and Ecological Interest (SBEI). The 150 floristic surveys conducted in the site allowed us to inventory 143 species distinguished with rare taxa majority that are distributed over 54 families and 123 genera. This reduced number of taxa reflects the alarming biodiversity deterioration of the SBEI. The study also enabled us to define the biological spectrum of the study area that is characterized by a significant abundance of Therophytes

The Vascular Flora of Tetraclinis Ecosystem in the Moroccan Central Plateau

The main objective of this study is to quantify the floral richness and diversity of Tetraclinis ecosystem in the Moroccan Central Plateau. The approach was based on over 300 floristic surveys covering the different parts of the Moroccan Central Plateau forests. It also entails the analysis and processing of data from studies in the region. The results indicate that there are 233 taxa belonging to 56 families

New records of three alien Solanum species in Morocco

Recent floristic surveys conducted in various regions of Morocco have revealed three new records of non-native vascular plants of the genus Solanum, namely, S. abutiloides Bitter & Lillo, S. bonariense L., and S. nitidibaccatum Bitter. The occurrence of these alien species in Morocco is documented here for the first time. For each species, information on its national habitat and distribution are given. More-over, the distinguishing morphological features of these three species are compared with the most similar species (including Moroccan Solanum species)

Effect of Plant Communities and Ecological Parameters on Soil Organic Carbon Stocks in the Mamora Forest, Morocco

Several studies on the assessment of soil organic carbon (SOC) stocks have been carried out at the global level. However, reliable information on SOC stocks is not readily available at the regional level. In addition, very few studies have assessed the factors responsible for the variation of SOC stocks, in particular the effect of plant communities. For this purpose, the main objective was to analyze the effects of three plant communities and ecological parameters on the SOC stock in the Mamora forest. Specifically, we looked to examine the relationships between SOC stock and plant communities and to define the main parameters that directly influence SOC stock. Ten soil profiles with three replications were sampled at each plant community, from which SOC stock was determined. To assess the effect of plant communities on SOC stocks, phytosociological surveys were carried out according to the phytosociological stigma method developed by Braun-Blanquet. The results show that SOC stocks in cork oak soils are characterized by high variability, with values ranging from 55 t ha-1 to 95 t ha-1. Indeed, the findings of this study showed that SOC stocks fluctuated significantly with plant communities. In addition, SOC stocks were also affected by the interactions between plant communities, the amount of litter and the density of the cork oak stand. These outcomes of this study highlight the critical need to incorporate community-specific carbon values into future carbon sequestration modeling

Native plant species growing on the abandoned Zaida lead/zinc mine site in Morocco: Phytoremediation potential for biomonitoring perspective.

This study aims to assess the level of metal contamination and the ecological risk index at the abandoned Zaida Pb/Zn mining site in eastern Morocco and identify native plant species found on the site that can be used in site rehabilitation through phytoremediation strategies. Samples from seven native and abundant plant species at the site, along with their rhizospheric soils, were collected and analyzed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to determine the concentrations of various metal(loid)s, including As, Cu, Ni, Cd, Sb, Zn, and Pb. Indicators of soil pollution and ecological risks were also assessed, including the enrichment factor (EF), pollution index (PI), and ecological risk index (ERI). The Biological Accumulation Coefficient (BAC), Translocation Factor (TF), and Biological Concentration Factor (BCF) of plant samples were calculated. The results reveal polymetallic soil contamination, with notably higher concentrations of Pb, Cu and Zn, reaching respectively 5568 mg kg-1 DW, 152 mg kg-1 DW, and 148 mg kg-1 DW, indicating a significant potential ecological risk. The enrichment factor (EF) was also assessed for each metal(loid)s, and the results indicated that the metal contamination was of anthropogenic origin and linked to intensive mining activities in Zaida. These findings are supported by the pollution index (PI) ranging from 1.6 to 10.01, which reveals an extremely high metal(loid)s pollution level. None of the plant species exhibited a hyperaccumulation of metal(loid)s. However, Artemisia herba alba demonstrated a strong capacity to accumulate Pb in its aboveground parts, with a concentration of 468 mg kg-1 DW. Stipa tenacissima, Retama spherocarpa, and Astragalus armatus, showed a significant Pb accumulation in their roots reaching 280, 260, and 256 mg kg-1 DW.respectively. Based on BAC, TF, and BCF, Stipa tenacissima exhibited potential for Ni and Cd phytostabilization, as well as the ability for Zn phytoextraction. Additionally, Artemisia herba alba displayed the capability to phytoextract Cd and had a high propensity to translocate all the studied metal(loid)s. Astragalus armatus has the potential to be used in the phytostabilization of Zn and Ni, as well as for the phytoextraction of As and Sb. These native species from the Zaida site, although not hyperaccumulators, have the potential to contribute significantly to the phytoextraction or phytostabilization of potentially toxic elements (PTEs). Moreover, they can serve as vegetative cover to mitigate the erosion and dispersion of metal(loid)s

Contribution of geomatics tools to the study of the spatio-temporal evolution of forest stands of the Maamora forest in the face of global changes

A better knowledge of the land use of an environment is based on the establishment and comparison of various spatio-temporal situations of the different components of this space. This work is part of a research on the dynamics of the Maamora forest. It aims to show the contribution of the use of geomatics tools in the evaluation of dynamics of forest cover and therefore the evaluation of the impact of global changes and previous forest management methods. The approach followed for the assessment of forest cover in 1984, 1994, 2004, 2014 and 2019, was based on satellite images of Landsat 5 and Landsat 8, with a spatial resolution of 30 m. The classification supervised by the “Support Vector Machine” (SVM) algorithm made it possible to develop forest cover maps for the dates selected and subsequently to evaluate the changes. The classification evaluation showed a Kappa coefficient over 87% and an overall accuracy over 90% for all the selected dates. The results showed a great dynamic of the forest cover between 1984 and 2019 with two significant periods. The first one is 1984-1994 when areas of cork oak and acacia fell respectively by 20% and 39% in favor of other introduced forest species, mainly eucalyptus and pines, which increased respectively by 28% and 74%. For the second period 1994-2019, there was a reversal trend of regression of cork oak’s area towards an increase of 11%, while the area of eucalyptus plantations was generally stabilized and that of pines and acacia stands fell by 37% and 33% respectively. These results make it possible to provide decision-makers with tools for the future management of the space

Effect of plant Communities and Ecological Parameters on Soil Organic Carbon Stocks in the Mamora Forest, Morocco

Several studies on the assessment of soil organic carbon (SOC) stocks have been carried out at the global level. However, reliable information on SOC stocks is not readily available at the regional level. In addition, very few studies have assessed the factors responsible for the variation of SOC stocks, in particular the effect of plant communities. For this purpose, the main objective was to analyze the effects of three plant communities and ecological parameters on the SOC stock in the Mamora forest. Specifically, the authors looked to examine the relationships between SOC stock and plant communities and to define the main parameters that directly influence SOC stock. Ten soil profiles with three replications were sampled at each plant community, from which SOC stock was determined. To assess the effect of plant communities on SOC stocks, phytosociological surveys were carried out according to the phytosociological stigma method developed by Braun-Blanquet. The results show that the SOC stocks in cork oak soils are characterized by high variability, with values ranging from 55 t•ha-1 to 95 t•ha-1. Indeed, the findings of this study showed that the SOC stocks fluctuated significantly with plant communities. In addition, SOC stocks were also affected by the interactions between plant communities, the amount of litter and the density of the cork oak stand. These outcomes of this study highlight the critical need to incorporate community-specific carbon values into future carbon sequestration modeling

Effect of Tree Shelters and Regeneration Method on Survival and Growth of Cork Oak Plantations in the Maamora Forest, Morocco

Forests are under intense human pressure, hindering their restoration. A potential solution to regeneration problems is the adoption of tree shelters, which have demonstrated protective benefits in the early establishment of forest plantations. A 9-year study was conducted in the Maamora forest (Morocco) to evaluate the effects of tube shelters and regeneration methods (direct seeding and seedling) on the growth and survival of cork oak (Quercus suber) plantations. A split-plot design was developed with three replicates of 36 plants for each of the four shelter treatments, including T0 (control), T1 (Tubex 1.20 m), T2 (Tubex 1.50 m), and T3 (Tubex 1.80 m) for a total of 964 plants, where periodic inventories were conducted to assess plant survival and growth. Our results show regeneration methods and shelters significantly influenced the survival of cork oak. Direct-seeded plants were more successful than those from seedlings, presenting survival rates of up to 97%. Despite a minimal shelter effect at the beginning, their positive influence was strong later on. Only plants installed with the 1.20 m shelter had an overall success rate of over 50%. Regeneration method had a strong influence on height and diameter growth, with seedling units showing taller plants initially, which shifted to direct-seeded plants in subsequent years. Conversely, the effect of shelters on growth parameters was generally non-significant. Nonetheless, sheltered trees exhibited greater height and diameter than unsheltered trees, particularly in the latter years. Sheltered plants showed an overall faster rate of vertical growth, while unsheltered plants showed faster radial growth

Effect of Tree Shelters and Regeneration Method on Survival and Growth of Cork Oak Plantations in the Maamora Forest, Morocco

Forests are under intense human pressure, hindering their restoration. A potential solution to regeneration problems is the adoption of tree shelters, which have demonstrated protective benefits in the early establishment of forest plantations. A 9-year study was conducted in the Maamora forest (Morocco) to evaluate the effects of tube shelters and regeneration methods (direct seeding and seedling) on the growth and survival of cork oak (Quercus suber) plantations. A split-plot design was developed with three replicates of 36 plants for each of the four shelter treatments, including T0 (control), T1 (Tubex 1.20 m), T2 (Tubex 1.50 m), and T3 (Tubex 1.80 m) for a total of 964 plants, where periodic inventories were conducted to assess plant survival and growth. Our results show regeneration methods and shelters significantly influenced the survival of cork oak. Direct-seeded plants were more successful than those from seedlings, presenting survival rates of up to 97%. Despite a minimal shelter effect at the beginning, their positive influence was strong later on. Only plants installed with the 1.20 m shelter had an overall success rate of over 50%. Regeneration method had a strong influence on height and diameter growth, with seedling units showing taller plants initially, which shifted to direct-seeded plants in subsequent years. Conversely, the effect of shelters on growth parameters was generally non-significant. Nonetheless, sheltered trees exhibited greater height and diameter than unsheltered trees, particularly in the latter years. Sheltered plants showed an overall faster rate of vertical growth, while unsheltered plants showed faster radial growth