Abdelkrim Benaradj

Lygeum spartum, a steppe formation in the arid Mediterranean region, can be found in the high Oranian steppe plains of Naâma. A spring 2020 phytoecological study was conducted on a steppe community in the Naâma region of western Algeria. This group occupies vast steppe areas in the high plains of Oran. This study used qualitative and quantitative floristic analysis to examine ecological factors. This study conducted 50 phytoecological surveys to evaluate the formation’s floristic composition and ecology. This method allows for the inventory and ecological characterization of natural vegetation in relation to edapho-climatic conditions. The data was analyzed using Factor Correspondence Analysis. The floristic analysis shows less than 20% vegetation cover. Quantitative analysis shows a diverse floristic composition of 47 species from 19 families. The identified plant species mainly belong to the Poaceae and Asteraceae families. Esparto grass accounts for 41% of the floristic composition. The biological spectrum includes therophytes, chamaephytes, and hemicryptophytes. The biogeographical components show 13 taxa with Mediterranean affinity. Floristic data shows three plant subgroups. (i) Lygeum spartum and Caroxylon vermiculatum dominate these gypso-halophyte steppes. (ii) Psammophytes like Thymelaea microphylla dominate these degraded steppes. (iii) Therophytes like Atractylis caespitosa, Peganum harmala, and Plantago albicans characterize another type of degraded steppe. The esparto group is ecologically versatile due to its climate and soil adaptability. This group is prominent in the South Oranian steppes.

The progressive silting up of dams in arid and semi-arid zones is a major problem, affecting storage capacity, the durability of hydraulic structures, and the sustainable management of water resources. In this context, the Brézina Dam, located in the El-Bayadh province (southwest Algeria) and with a capacity of approximately 123 million m³, was studied to characterize the morpho-sedimentary evolution of the catchment and reservoir over the period 2000–2025. The methodological approach is based on the spatio-temporal analysis of multi-date Digital Terrain Models (DTMs) using Google Earth Engine (GEE) and the calculation of the ?DTM, allowing for the identification and quantification of erosion and sedimentation zones. Descriptive and inferential statistical indicators, combined with automated thematic maps, were used to analyze topographic variations and estimate sediment volumes.The results highlight a dynamic dominated by sedimentation, with variations in the DEM (Digital Elevation Model) ranging from ?12 to +25 m and a statistically significant average increase in elevation (t ? 28.04; p < 10?¹?). Sedimentary deposits are mainly concentrated in valleys and near the dike, particularly in the 900–910 m elevation range observed in 2025. Volumetric analysis indicates that 59.54% of the surface area is affected by low-intensity sedimentation, compared to 31.42% affected by erosion, with an estimated eroded volume of 3.92 million m³ and a net positive sediment budget of +8.81 million m³.Beyond the hydraulic challenges, these results highlight the potential for valorizing dredged mud as organo-mineral amendments to improve the structure, water retention and fertility of sandy soils in arid areas, thus contributing to integrated and sustainable management of dams and agricultural systems. Keywords: Siltation, valorization, erosion, sedimentation, remote sensing, dam.

This study focuses on the phytoecological characterization of Pistacia atlantica in the Saharan Atlas of Naâma (western Algeria). A floristic inventory, conducted through 32 field surveys, identified significant biological diversity. The results reveal a systematic structure composed of 103 plant species, distributed across 81 genera and 30 botanical families. This floristic richness testifies to the importance of diversity and ecological plasticity in this pre-forest community within the Saharan Atlas. The Pistacia atlantica community exhibits unique floristic diversity, combining endemic Mediterranean and Saharan species adapted to the arid bioclimatic environment. This drought-resistant and structurally rich vegetation constitutes a valuable biological resource requiring conservation measures in the face of anthropogenic and climatic threats.

Algeria has a diverse bird fauna, yet data from arid and semi-arid regions are scarce. To fill this knowledge gap, we conducted a study on the composition and conservation status of bird species of Djebel Aïssa National Park in the Naama province of Southwestern Algeria between September 2021 and September 2023. We collected data by using progressive frequency sampling (PFS) and line transects, which allowed us to systematically assess bird species across different habitats within the park. We recorded 94 species of birds belonging to 11 orders and 27 families. Passeriformes was the most abundant order, comprising 16 families and 67 species. The bird species detected were predominantly sedentary (50%) or wintering (39%), and some were visiting (8%) or migratory (3%). Most species were insectivores (45%), followed by granivores/insectivores (24%), carnivores (13%), omnivores (7%), granivores (6%), and carnivores/insectivores (5%). Most bird species were classified as “Least Concern” by the IUCN Red List, two species were “Near Threatened”, and one was “Vulnerable”. In addition, 29 species are protected under Executive Fiat 12–235 of 24 May 2012. Our study provides a baseline for future monitoring efforts and a basis for the development and implementation of conservation strategies in Djebel Aïssa National Park and the surrounding regions.

Flooding is a major hazard in semi-arid regions, where intense but irregular rainfall interacts with fragile soils. Assessing soil properties is essential for understanding vulnerability and supporting effective watershed management. This study analyzes the physicochemical characteristics of soils in the Oued Tinn watershed (northwestern Algeria), part of the Macta basin, with the aim of evaluating their susceptibility to flooding caused by rainwater stagnation. Forty soil profiles were collected across 29 sub-watersheds and analyzed for texture, pH, organic matter, calcium carbonate, electrical conductivity, and total nitrogen. Multivariate statistical methods, including Principal Component Analysis (PCA) and Hierarchical Ascending Classification (HAC), were applied to identify the main factors influencing hydrological behavior and to classify soils into vulnerability groups. Results showed that soils are predominantly clayey to clay-loam, with neutral to basic pH, low organic matter, and moderate calcium carbonate content. PCA highlighted texture and carbonate levels as the primary drivers of variability, while HAC grouped the profiles into five distinct classes. Clay- and silt-rich soils with high carbonate content emerged as the most vulnerable due to low permeability, whereas sandy soils were less prone to stagnation but more exposed to fertility loss and erosion. These findings emphasize the need to integrate soil properties into flood risk assessments in semi-arid landscapes. The combined use of soil analysis, multivariate statistics, and spatial mapping provides a replicable framework for identifying high-risk areas and guiding sustainable land-use and soil conservation practices under increasing climatic pressures.

Naâma province occupies 3 million hectares, rich in natural resources (biological, edaphic and water), but unfortunately it undergoes a process of continuous degradation due mainly to clearing, overgrazing, overexploitation, desertification and sand encroachment. This requires the development of steppe rangelands (protection, rehabilitation and restoration) by adopting biological measures (pastoral plantations, creation of protected areas, dune fixations, as well as afforestation and the large green dam project). The result of this approach is characterized by a particular adaptation of different measures to the biophysical characteristics of the environment and different actions undertaken for restoration and rehabilitation that are part of a national strategy for pastoral improvement of degraded steppe rangelands. The sustainability of the various measures taken requires participatory management of the local population in rehabilitation programmes.

The Atlas pistachio tree (Pistacia atlantica) is a woody deciduous species from the family Anacardiaceae. It thrives in the steppe plains and Saharan Atlas of the Naâma region in south-western Algeria. This tree is well known in traditional Algerian medicine for its active phenolic compounds, particularly those found in its seeds and leaves. To promote its use, an ethnobotanical survey was conducted among herbalists and other knowledgeable individuals in the Naâma region, utilizing 100 questionnaires divided among 25 municipalities. The findings revealed that leaves (42%) and fruits (31%) are the most commonly utilized parts. The predominant preparation methods include decoction and grinding, but also other forms are popular, such as herbal tea or powder mixed with honey, dates, milk, or water. Administration is mainly oral, though external applications are also common, particularly for localized issues. The most frequently treated conditions include oral diseases, stomach ulcers, respiratory infections, Malta fever, and skin rashes, with values of fidelity index ranging from 2% to 14%. Most reported outcomes from these treatments are positive, indicating either cures or improvements. The frequency of use for this plant among the respondents is 100%, underscoring its significant cultural importance. The informant consensus exceeded 0.70, reflecting a robust therapeutic understanding of the plant. The global knowledge index regarding its uses is notably high, highlighting its essential role in the community for medicinal and other applications.

The present study contributes to the identification of cropping systems applied to traditional argosystems in Naama region (southwest of Algeria). A series of farm surveys were conducted for 30 oases farmers using a semi-structured questionnaire on aspects related to systemic typology crops practiced in Moghrar and Tiout oases in Naama region. The obtained results showed a diversification of crops grown intensively in these oases. They are characterized by the practice of mixed food crops cultivation in underlying strata, associated with family-type livestock farming. Truly, the presence of 35 different crops: date palm cultivar, 5 forage crops, 16 market gardens and 13 fruit trees has been recorded. This oasis system represents an ancestral oasis heritage built and maintained by the local population owing to a careful management of natural resources.

This research paper presents a detailed investigation into the morphometric characteristics of sub-basins within the Naama region of Algeria, aiming to prioritize areas vulnerable to soil erosion and runoff risks. Focusing on five key sub-basins that collectively represent 75% of the Wilaya of Naama, the study employs a comprehensive methodological framework, integrating morphometric analysis (MA), weighted sum analysis (WSA), principal component analysis (PCA), and the novel approach of compositional data analysis (CoDA). Through the rigorous evaluation of sixteen distinct morphometric parameters selected based on their relevance to hydrological and geomorphological processes that influence erosion and runoff, this research provides a nuanced understanding of the factors influencing erosion susceptibility within each sub-basin. The analysis reveals a clear hierarchy of sub-basins based on their calculated compound parameters, effectively classifying them into high, moderate, and low priority categories for targeted intervention and resource allocation. The results highlight the Ain Sefra and Wadi Er Rosafa sub-basins as the highest priority areas, collectively encompassing 31.51% of the wilaya and posing the most significant threats of runoff and soil erosion. This identification allows for the prioritization of conservation efforts and the implementation of tailored management strategies in these critical areas. Furthermore, the integration of multiple prioritization approaches, including the innovative application of CoDA, ensures a robust and comprehensive assessment of the sub-basin landscapes. This multi-faceted approach provides a more nuanced understanding of the complex interplay between various morphometric parameters and their influence on erosion and runoff potential. The findings of this research have significant implications for sustainable land and water resource management within the Naama region. By identifying and prioritizing vulnerable sub-basins, the study provides a crucial foundation for informed decision-making, enabling stakeholders to implement targeted interventions and mitigate the detrimental impacts of soil erosion and excessive runoff. Moreover, the methodological framework presented in this research paper offers a valuable blueprint for similar studies in other regions facing comparable challenges. The cost-effective and time-efficient nature of the approach makes it a practical tool for prioritizing erosion and runoff risks in arid and semi-arid environments worldwide, contributing to the broader goals of environmental sustainability and land degradation neutrality.

The steppe space of Naâma covers an appreciable pastoral area of 3 million ha (i.e., more than 74% of the area of the wilaya). It is essentially characterized by plant formations that are very diversified by the abundance of bunchgrasses, a shrub layer (chamephytes), and an herbaceous layer including therophytes (annual species). This space is mainly made up of alfa pastures (Stipa tenacissima), spartan pastures (Lygeum spartum), psammophytic pastures in Drinn (Stipagrostis pungens), and bushy steppe pastures with Remth (Hammada scoparia). This chapter consists of an ecological characterization of steppe groups in the South Oran region of Naama with the aim of better understanding the dynamics of vegetation and better understanding the ecological factors that govern these plant formations.