The species belonging to the genus Pistacia possess ecological, economic, and medicinal value. They show a very high ecological plasticity. This research is a contribution to the study of the intraspecific diversity and variability of 10 populations of Pistacia lentiscus in different bioclimates. Nine locations in Algeria and one site in France have been selected in order to understand the strategies developed by this species under extreme conditions, including altitude and aridity, and to identify the adaptive processes that can be observed based on the morphological and ultrastructural features of the leaf. As a result of this research, we have collected a large quantity of important information on morphological and microphytodermal leaf variability for the ten studied populations. The statistical analyses showed a very important difference in the studied characteristics between these populations. It has been demonstrated that environmental factors also have a significant impact on the heterogeneity of most measured leaf features. Moreover, the observations with the scanning electron microscope (SEM) enabled us to highlight new characteristics of the studied species, such as the glandular trichomes on the leaflets and embedded stomata in the epidermis. These criteria could supplement the existing morphological characteristics used in the systematic classification of the Pistacia genus. Overall, the studied species have shown xeromorphy features, which give them the opportunity to be used in desertification mitigation programs, due to their ability to withstand conditions of extreme aridity.

Background: The problem of soil contamination is a major concern of emerging countries. Heavy metals such as lead, cadmium, copper, zinc, and mercury cannot be biodegraded, and therefore, persist in the environment for long periods. It has become essential to develop efficient techniques for decontamination of polluted soils. One of these techniques, phytoremediation, is economically viable and compatible with environmental preservation policies. The application of phytoremediation in salty areas requires the use of plants that are able to tolerate heavy metals and high soil salinity. Atriplex halimus is one of the species with a great purification potential, which is a spontaneous halophyte species, and endowed with a fairly important aerial and root biomass. This study aimed to determine the effect of cadmium sulfate (CdSO4 ) on the germination and growth of A. halimus, and to assess its ability to accumulate cadmium and proline. Methods: This is an experimental study of the tolerance of A. halimus to increasing concentrations of CdSO4 by an in vivo test. This study aimed to assess the degree of tolerance of this perennial species towards different concentrations of CdSO4 . Results: The results show a non-significant effect of CdSO4 on the seed germination rate and growth of the aerial and root parts. However, a significant accumulation of proline was observed especially in the aerial part, whereas the highest cadmium content was recorded at the roots. Conclusion: According to the results, this species can be used in phytoremediation to decontaminate soils contaminated by heavy metals.

To combat desertification and land degradation in arid and semi-arid zones, the government has adopted an approach of rehabilitation of pasturelands through forage plantations. This program was launched at the beginning of the 1990s and, to date, there has been no global or national study on the sustainability of the program, particularly its economic profitability. Our work’s principal objective was to perform an economic analysis of the forage plantation program across the different periods since the creation of the program until the year 2020, focusing on the economic evaluation parameters of the projects, such as mean annual net income, net present value, annuity of the net present value, profitability index and payback period, based on the data collected from the official institutions. The results showed that the forage plantation program significantly contributes to sustainable development in steppe areas.

This study aims to examine the impact of dendrometric factors on the natural regeneration of red juniper (Juniperus phoenicea L.) in the semi-arid region, located in the central steppe area. Across ten selected homogeneous stations, a total of 100 temporary observation plots, of 400 m² each, were surveyed via a mixed sampling method (stratified and systematic). Within each plot, dendrometric variables were measured (total height, dominant height, density and cumulative canopy area). This process involved evaluating the natural regeneration of red juniper as well. Data analysis highlighted that the regeneration of red juniper decreases with the magnitude of stand attributes, particularly stand density, dominant height, and canopy projection area. Nonetheless, it is proportional to the average total height and the dominant canopy projection area. The maximum regeneration density of red juniper was observed in stands where canopy cover is moderate (between 16% and 20%), and the density of adult trees ranges between 100 and 115 trees/ha. Keywords: Juniperus phoenicea L. sensu lato; natural regeneration; plant density; dendrometric parameters; steppe area; African semi-arid; North Africa.