Search Results (241)

The management of water resources is a critical factor in the emergence of civilizations, particularly in arid regions like the Arabian Peninsula. The ancient Marib Dam represents a systematic application of hydraulic planning within the Sabaean civilization. This study analyzes the scientific rationale behind the dam’s site selection by assessing key hydrological and geomorphological factors using Geographic Information Systems (GISs) and Weighted Overlay Analysis (WOA). The analysis revealed that the dam’s location precisely corresponds with a (very high) potential runoff accumulation zone, a critical area constituting only 0.8% of the total landscape studied. By providing this quantitative assessment, this study moves beyond historical interpretation to offer the first geospatial evidence that the dam’s site selection was deliberate and quantitatively informed, establishing a replicable model for the field of archaeohydrology. Full article

Cyanobacterial species in the Arabian Peninsula region display a diverse range of potential biotechnological application. This review summarizes the cyanobacteria diversity found in the Peninsula region, the bioactive compounds found in these species, and the several health benefits and applications. The Arabian Peninsula region comprises a wide range of cyanobacteria with representatives from the orders Oscillatoriales, Chroococcales, Stigonematales, and Nostocales. These microorganisms produce specialized metabolites such as photosynthetic pigments, pigment–protein complexes, lipopeptides, phenolic compounds, and unique secondary metabolites. Many of the metabolites offer beneficial biological functions including antioxidants, antibacterial, anti-cancer, anti-inflammatory antiviral, and neuroprotective ones. In addition to the medical-related practices, cyanobacteria in the Peninsula region might have several other applications. Other probable uses include their potential bioremediation capability to remove pollutants or heavy metals, as a potential biohydrogen source for renewable energy, and as biofertilizers and soil enhancement to support sustainable agriculture; other useful applications include bioplastics production (polyhydroxyalkanoates), soil microbiota improvement, and methane reduction. The review highlights the potential diverse biotechnological applications of Arabian Peninsula cyanobacteria toward bioremediation, bioplastics, ecosystem regeneration, biofertilizers, bioenergy, and agro-sustainability, as well as human health. This review highlights the importance of the further exploration and exploitation of these resourceful microorganisms for sustainable development in the Arabian Peninsula region. Full article

The peach fruit fly, Bactrocera zonata (Saunders) (Diptera: Tephritidae), is a climate-sensitive agricultural invader that threatens fruit production across the Arabian Peninsula, yet its realized climatic niche and future exposure under warming remain insufficiently resolved. We used Maximum Entropy (MaxEnt) modeling to quantify current and projected habitat suitability across the region (~3.2 million km²) under two Shared Socioeconomic Pathway scenarios (SSP1-2.6 and SSP5-8.5) for the 2050s and 2070s, based on 55 spatially filtered occurrence records and seven non-collinear environmental predictors, with sampling bias controlled using a Gaussian kernel density bias file. Model performance was robust, with mean training AUC of 0.922 ± 0.011 (SD) and mean TSS of 0.538 ± 0.115 (SD; range: 0.368–0.692), indicating moderate variability across replicates. Suitability was governed primarily by elevation, mean temperature of the driest quarter (Bio 9), mean diurnal temperature range (Bio 2), and precipitation of the coldest quarter (Bio 19), which together contributed over 97% of the model output, indicating strong climatic and topographic control on range persistence. Under present conditions, 790,714 km², or 28.38% of the study area, was suitable, concentrated in the southwestern highlands of Saudi Arabia and Yemen, the Omani mountain ranges, and coastal fringes of the Arabian Gulf and Gulf of Oman. Future projections showed a consistent net contraction of suitable habitat across all scenarios, from 7.4% under SSP1-2.6 in the 2050s to 28.0% under SSP5-8.5 in the 2070s. In all cases, contraction exceeded expansion, although the eastern Omani highlands remained a potential climatic refugium. These patterns indicate that warming is likely to reorganize rather than uniformly expand suitability, providing a spatial basis for climate-informed biosecurity, surveillance, and regional pest management. Full article

Brominated flame retardants (BFRs) are widely used in automotive polymers and electronic components, yet vehicles remain an under-characterized and potentially high-exposure microenvironment, particularly in hot climates. This study provides the first comprehensive assessment of BFR occurrence, sources, and exposure risks in vehicle dust from Saudi Arabia, addressing a critical regional data gap. This study systematically investigates the occurrence, compositional patterns, sources, and human exposure risks of polybrominated diphenyl ethers (PBDEs) and selected alternative BFRs in dust from 80 vehicles (domestic cars and taxis; model years 2015–2022) operating in Jeddah, Saudi Arabia. Dust samples were collected using a standardized vacuuming protocol, extracted and cleaned using solvent extraction and silica SPE, and analyzed via GC–NCI–MS. Both legacy PBDE congeners and emerging alternatives (including DBDPE and TBB) were consistently detected, with BDE-209 dominating the overall BFR burden with mean concentrations of 6560 ng/g in domestic vehicles and 5454 ng/g in taxis, with maximum values reaching 220,860 ng/g. Lower-brominated PBDEs occurred at substantially lower concentrations, reflecting the ongoing global transition away from Penta- and Octa-BDE formulations. Taxis exhibited generally higher concentrations than domestic vehicles, likely due to prolonged occupancy, increased usage intensity, and enhanced dust resuspension dynamics. Multivariate analysis (PCA and correlation) revealed two distinct source categories: (i) legacy Penta-BDE-related congeners associated with polyurethane foam and textile materials and (ii) high-brominated PBDEs and DBDPE linked to hard plastics and electronic components. Human exposure assessment demonstrated that dust ingestion is the dominant exposure pathway, while dermal and inhalation routes contribute minimally. Non-carcinogenic hazard indices (HI) were well below unity for all compounds (HI < 1.67 × 10⁻⁶), and incremental lifetime cancer risks (ILCR) for BDE-209 remained within or near accepted risk thresholds (7.52 × 10⁻⁶–1.04 × 10⁻⁵), although occupational exposure among taxi drivers was consistently higher. Overall, the results demonstrate that modern vehicle cabins act as significant microenvironments for chronic BFR exposure, particularly under high-temperature conditions. Despite generally low estimated risks, the combined effects of chemical persistence, bioaccumulation potential, and mixture toxicity—amplified by extreme in-cabin temperatures—highlight vehicles as overlooked yet significant exposure environments. These findings provide the first comprehensive dataset for the Arabian Peninsula and emphasize the need for climate-sensitive exposure assessment, safer material design, and targeted mitigation strategies in vehicle interiors. Full article

The genus Desmidorchis Ehrenb. (Apocynaceae) is a characteristic component of the succulent flora of the Arabian Peninsula, where high levels of endemism and increasing environmental pressures highlight the need for integrated genomic and conservation research. This study assessed the conservation status of three ethnomedicinally important endemics—D. adenensis, D. arabica, and D. awdeliana—and characterizes their complete plastomes to resolve their evolutionary and temporal history. Conservation assessments were conducted following IUCN Red List criteria, and complete plastomes were sequenced and compared within a dataset of 15 subtribe Stapeliinae taxa. Comparative analyses examined the genome structure, divergence hotspots, repetitive sequences, codon usage bias, and selection pressure, while divergence times were estimated using fossil-calibrated molecular clock analyses. All three species were classified as Near Threatened (NT), primarily due to anthropogenic and environmental pressures. Plastome analyses revealed a highly conserved genome structure; however, hypervariable regions, particularly ycf1 and clpP1, exhibited elevated sequence divergence and phylogenetic informativeness. Simple sequence repeats (SSRs) were also identified as potentially informative features at the genus level. Codon usage and Ka/Ks analyses further indicated that most plastid protein-coding genes are under strong purifying selection, whereas only a few loci, particularly clpP1, showed comparatively elevated evolutionary rates. Phylogenomic analyses supported the monophyly of Desmidorchis, with molecular dating indicating recent Pleistocene diversification (~0.34–1.51 Ma), potentially associated with Quaternary climatic oscillations. Overall, this study provides an important genomic foundation for future taxonomic, evolutionary, and conservation studies of rare Arabian taxa. Full article

A new species of Scorpio Linnaeus, 1758 is described from Al Ula Governorate, Al Madinah Province, Saudi Arabia. Scorpio furvus sp. nov. is distinguished from closely related congeners, including S. fuscus, S. kruglovi, S. palmatus, S. jordanensis, and S. yemenensis, by a unique combination of morphological characters notably the granulation pattern of the pedipalp chela, metasomal proportions, pectinal structure and length, and overall dark coloration. Morphometric comparisons further support its distinct status. The discovery of this species highlights the underestimated diversity of the genus Scorpio in the Arabian Peninsula and reinforces the view that the Scorpio maurus complex comprises multiple geographically restricted taxa requiring continued integrative taxonomic investigation. Full article

Ground-level ozone (GLO₃) poses a critical threat to public health and the success of the Saudi Green Initiative, yet its long-term spatiotemporal evolution across the Arabian Peninsula remains poorly constrained. Utilizing CAMS-derived mixing ratios (1000–850 hPa) from 2003 to 2024, this study identifies a major systemic regime shift occurring in 2016–2017, marking a transition toward a more O₃-enriched atmospheric state across Saudi Arabia. While the early study period was characterized by pronounced spatial heterogeneity, post-2017 diagnostics reveal a synchronized intensification of GLO₃, particularly within the urban industrial belts of the Eastern and Western Provinces. Statistical trend metrics, including Mann–Kendall and regime-shift detection, show a persistent upward trend in GLO₃ concentrations, most significantly during winter and over the southwestern highlands. These trends are robustly coupled with increasing boundary-layer height, temperature, and UV-B radiation, alongside shifting precursor stoichiometry (CO, VOCs, NO_x) that separates titration-dominated from production-dominated regimes. Our results suggest that this mid-decade intensification reflects a convergence of anthropogenic forcing under Saudi Vision 2030 and shifting regional climatic drivers. By uncovering the transition from localized variability to kingdom-wide synchronization, this research provides a process-based foundation for targeted air quality management and the safeguarding of regional sustainability frameworks. Full article

Regular social, economic and agricultural interactions occurred between the Horn of Africa and Southern Arabian Peninsula for millennia, raising questions about potential geo-culinary exchanges, including of the little-studied fermented flatbreads produced in these areas. A comparative analysis of Somali laxoox/canjeero, Ethiopian injera, Sudanese kisra and Yemeni/Saudi lahoh was conducted by combining a literature review and consultations with 17 local experts, then processing the data in a hierarchical cluster analysis to quantify “biocultural” diversity. In an interdisciplinary approach, technical aspects (bread appearance, ingredients, and production stages) and cultural characteristics (consumption patterns and social function) were considered to identify key descriptors of the breads. A dendrogram generated through cluster analysis of a binary (0/1) matrix, structured with the key descriptors, showed that each bread has a distinct biocultural identity, and enabled the quantification of their similarities. Somali laxoox/canjeero and Yemeni/Saudi lahoh had a 64% similarity to each other (Jaccard index); each had a 53% similarity to Ethiopian injera; while all of them were 41% similar to Sudanese kisra. Hierarchical cluster analysis, applied for the first time to flatbreads, contributes to their comprehensive characterization and comparison in this unique geographic region and lays the foundations for policies to protect their identity and quality. Full article

The desert ecosystem harbors a resilient microbial community that sustains plant life under extreme stress. Understanding the endophytic microbiota of desert flora provides key insights into how these microorganisms enable plant survival and maintain ecological balance in arid landscapes. To date, the endophytic bacterial communities of dominant desert plants in the Arabian Peninsula have not been comprehensively characterized. Here, we investigated the endophytic microbiota of five co-adapted desert species, namely, Schweinfurthia papilionacea, Sesuvium verrucosum, Ochtocloa compressa, Helianthemum nummularium, and Convolvulus arvensis. These plants coexist in hyper-arid habitats and exhibit exceptional tolerance to drought, salinity, and nutrient scarcity. We hypothesized that, despite their phylogenetic divergence, these plants host functionally convergent microbial communities shaped by desert selection pressures. Using 16S rRNA gene amplicon sequencing, we obtained 3.4 million high-quality reads from 25 samples. Clustering at 97% similarity revealed 35 phyla and 17 dominant genera, highlighting notable microbial richness and ecological complexity. Alpha-diversity indices showed comparable species richness across hosts, while beta-diversity indicated community differentiation driven by environmental filtering. The dominant phyla included Pseudomonadota, Actinomycetota, Cyanobacteriota, and Bacillota, reflecting microbial adaptation to extreme desert conditions. Functional pathway prediction revealed enrichment of genes associated with DNA repair and protein turnover, suggesting metabolic flexibility and enhanced survival under stress. Overall, this study provides a comparative metagenomic insight into the endophytic bacterial communities of five desert plant species, uncovering a consistent pattern of functional convergence across diverse hosts. The findings suggest the presence of shared functional traits among the endophytic microbiota examined here, offering preliminary evidence for microbial contributions to plant resilience in arid environments. Full article

Rift Valley fever virus (RVFV) is a re-emerging, vector-borne pathogen endemic to Africa and the Arabian Peninsula, posing an increasing threat to human and animal health. Outbreaks have severe economic and social impacts on farmers, communities, and governments. Current diagnostic methods rely on PCR and ELISA; however, rapid pen-side tests would enable faster, cost-effective monitoring and outbreak control. Here, a species- and immunoglobulin class-independent capillary flow immunodiagnostic assay (lateral flow test; LFT) for detecting RVFV-specific antibodies is described. The assay uses a double-antigen approach, coupling the RVFV nucleocapsid protein, a major viral antigen, both to carbon nanoparticles and to a nitrocellulose membrane. The method was qualified with immune sera from sheep, calves, goats, and humans and benchmarked against a newly developed double-antigen ELISA and a commercial competition ELISA. Both the LFT and double-antigen ELISA demonstrated high specificity and sensitivity. This advancement brings RVFV-specific pen-side testing significantly closer to practical implementation. Full article

This experiment evaluated the productivity and economic viability of wheat under an integrated net house with a closed hydroponic irrigation system versus an open field. The objective was to assess this water-saving innovation under the Arabian Peninsula’s resource-constrained environments. The integrated system achieved markedly superior results, producing a grain yield of 13.0 t/ha—a 117% increase over the open-field yield of 6.0 t/ha. Biomass yield reached 40.0 t/ha versus 16.0 t/ha in open fields, a 150% improvement. These gains were attributed to controlled growing conditions and balanced nutrient delivery, which optimized plant performance and reduced environmental stress. The system also demonstrated significant savings in resources, offering enhanced resource-use efficiency per unit of production. The estimated total values of productivity and resource savings were substantial when adjusted to the land area conserved. For ROI, BCR, and IRR, hydroponic wheat production scored 3.13, 4.13, and 312.8% in season (1) vs. 1.97, 2.97, and 197.1% for open-field production. In season (2), hydroponics scored 1.62, 2.63, and 163.0% vs. 0.043, 1.04, and 4.32% for open fields. Higher yields in 2022/2023 resulted from 30 vs. 10 min/day of irrigation due to higher relative humidity reflecting higher rainfall in the first season. Full article

Background/Objectives: Candidozyma auris is the most frequent multidrug-resistant fungal infection in the Arabian Peninsula, with high mortality rates; therefore, new medications are in high demand. Microbes in marine habitats have genetically evolved to survive under a variety of adverse conditions, including severe temperatures, salinity, pH, and other stress factors, by generating various bioactive metabolites. These bioactive secondary metabolites have strong potential for use as antifungal agents. Due to the shortage of antifungal medications and the emergence of treatment resistance in C. auris, identifying new therapeutics from synthetic bacterial components or natural materials has become a necessity. Natural molecules have numerous advantages over synthetic substances, including structural variation and low toxicity. Few next-generation sequence-based investigations have been carried out on anti-Candidozyma auris bacterial species to identify potential therapeutic candidates. Therefore, the aim of this study is to identify biosynthetic gene clusters from marine bacteria using next-generation sequencing to discover novel drug compounds against multidrug-resistant C. auris. Methods: More than 68 isolates were collected from various marine environments using standard techniques. All isolates were tested against the multidrug-resistant C. auris. Scanning electron microscopy was utilized to investigate the cell membrane rupture caused by defused metabolites of the IRMCESH58L bacterium in C. auris. The Vibrio sp. IRMCESH58L genome was sequenced using long-read nanopore sequencing technology. Results: The bacterial strain IRMCESH58L, isolated from a fish liver sample, showed the highest and most constant activity against C. auris. An in vitro toxicity test found that IRMCESH58L had no cell cytotoxicity against HFF-1 cells. The assembled plasmid-free genome is 6,556,025 bp (48.93% G+C), with an N50 of 909243. Comparative analysis confirmed its relation to Vibrio alginolyticus. Conclusions: Whole-genome analysis of the native bacterial strain IRMCESH58L revealed various biosynthetic gene clusters, including those involved in surfactin’s biosynthesis of putative natural anti-C. auris chemicals, but no pathogenic protein-coding genes, emphasizing the importance of marine bacteria in the fight against C. auris. Following this in vivo study, therapeutic targets will later be selected for further pre-clinical studies. Full article

Background/Objectives: The Bedouins (nomads) and the Fellahin (farmers) of Jordan represent two distinct subpopulations, characterized by unique lifestyles, settlement patterns, and linguistic features. This study aims to estimate the frequency of 27 Y-STRs in these two Jordanian subpopulations, along with various forensic parameters and paternal lineage comparisons with neighboring populations. Methods: Twenty-seven Y-STRs were typed in two major Jordanian subpopulations: Bedouin nomads (n = 101) and Fellahin farmers (n = 98). The forensic and paternal genetic lineage parameters and Y-haplogroup predictions were estimated. In addition, we conducted multidimensional scaling (MDS) and centroid analyses based on the Fst distance matrix to compare the sampled communities with neighboring populations from the MENA region, East Africa, Southeast Europe, and South Asia. Results: The Y-haplogroup predictions revealed differences in the predicted lineage composition based on the Y-STR profiles. The predicted J1a2a1a2 haplogroup predominated among the Bedouins (74.3%), whereas the Fellahin displayed a more heterogeneous profile, with notable frequencies of J1 (40%) and J2 (17.3%). Furthermore, the Fellahin exhibited remarkable genetic diversity and significant gene flow, providing plausible evidence of kinship with neighboring Levantine and Arabian groups. In contrast, the Bedouins showed consistently lower diversity across multiple loci, indicating long-term tribal isolation and, therefore, the potential effects of genetic drift. The MDS and centroid analyses positioned the Fellahin among the genetically interconnected Middle Eastern populations, while the Bedouins were clustered with the Arabian Peninsula populations. Conclusions: Overall, the contrasting genetic signatures of the two Jordanian subpopulations reflect their settlement patterns and sociocultural practices. In addition, the Y-STR dataset generated in this study enhances the Jordanian forensic database and to extends our understanding of paternal lineage structures in the West Asian/Levantine region. Full article

The accurate representation of land cover is fundamental to sustainable land management, environmental monitoring, and spatial policy development. However, many national systems lack semantic interoperability, flexibility, and are often developed for narrowly focused purposes. This study presents an ontology-based approach to developing the Libyan National Land Cover Reference System (LLCRS) using the Land Cover Meta Language (LCML), defined in ISO 19144-2. The aim is to shift from fixed class labels to a structured set of observable descriptors—such as cover percentage, phenology, height, and spatial pattern—allowing for more precise, scalable, and interoperable representations of land cover. Using Libyan national classification schemes as a foundation, land cover classes were translated into LCML descriptors through iterative modeling and validation, supported by the Land Characterization System (LCHS) software. The resulting reference system offers a standardized, modular structure that facilitates crosswalks between national, regional, and global classification frameworks. It enhances consistency across mapping efforts and supports integration into national land monitoring workflows. The framework is tailored to Libya’s arid context but offers potential for adaptation and reusability in other arid/semi-arid regions, such as those in the Sahel or Arabian Peninsula, by adjusting descriptors to local environmental conditions while maintaining biophysical focus and excluding socio-economic or land-use dynamics. Full article

Orbea is a morphologically diverse lineage within the subtribe Stapeliinae, yet plastome evolution in Arabian taxa remains insufficiently characterized. This study reports the first complete chloroplast genomes of Orbea sprengeri subsp. commutata and O. wissmannii var. eremastrum and investigates plastome structure, sequence variability, and phylogenetic relationships across tribe Ceropegieae. Chloroplast genomes were assembled, annotated, and compared with 13 published plastomes representing major Ceropegieae lineages. Both Arabian plastomes displayed the typical quadripartite structure and identical gene content of 114 unique genes, including 80 protein-coding genes, 30 transfer RNA genes, and four ribosomal RNA genes. However, O. wissmannii var. eremastrum exhibited pronounced structural divergence, possessing the largest plastome recorded for the tribe (170,054 bp), an 8.9 kb expansion of the inverted repeat regions, and an 8.4 kb inversion spanning the ndhG–ndhF region. Comparative analyses revealed conserved gene order across Ceropegieae but identified six highly variable loci (accD, clpP, ndhF, ycf1, psbM–trnD, and rpl32–trnL) as potential DNA barcodes. Selection pressure analyses indicated strong purifying selection across most genes, with localized adaptive signals in accD, ndhE, ycf1, and ycf2. Phylogenomic reconstruction consistently resolved the two Arabian Orbea taxa as a distinct clade separate from the African O. variegata. This study fills a gap in Ceropegieae plastid genomics and underscores the importance of sequencing additional Orbea species to capture the full extent of genomic variation within this diverse genus. Full article