Oxidative stress responses of the giant clam (Tridacna maxima (Röding, 1798)) to seasonal variations and contaminations on the Red Sea Coast of Egypt

Statistical downscaling of global climate projections over the Egyptian Red Sea coast

Reducing charge carrier transport losses, improving selectivity, and minimizing non-radiative recombination are essential for enhancing the efficiency and stability of perovskite/silicon tandem solar cells. We used a hybrid two-step perovskite deposition method that is compatible with industry-standard textured silicon, incorporating a perovskite surface treatment based on 1,3-diaminopropane dihydroiodide. The interaction of this molecule with the perovskite surface increased the majority charge carrier concentration at the electron-selective contact, which reduced interfacial recombination. Simultaneously, this field-effect passivation increased the electron concentration across the entire intrinsic perovskite absorber, which increased conductivity and reduced transport losses. Combined, this yields high-performance, fully-textured perovskite/silicon tandem solar cells, achieving a 1-sun AM1.5G conversion efficiency of 33.1% with an open-circuit voltage of 2.01 volts, and an extended outdoor stability in the Red Sea Coast.

Obligate marine fungi associated with mangroves are a unique group that fulfils significant ecological functions in mangrove ecosystems. The present study aimed to assess the antimicrobial, antioxidant, and anticancer potentials of the marine fungus "Swampomyces armeniacus" isolated and characterized (on both morphological and molecular levels) from mangroves located in RAS Mohamed natural protectorate on the Red Sea coast; along with determining the metabolomics profiling of the candidate species. The antimicrobial capability was assessed via the agar well diffusion method against 6 strains (Bacillus cereus, Staphylococcus aureus, Shigella sonnei, Pseudomonas aeruginosa, Candida albicans, and Aspergillus niger) alongside determining the minimum inhibitory concentration (MIC) by two-fold microdilution method. The study findings indicated that S. armeniacus crude extract had antimicrobial activity against all test strains whereas the strongest effect was against B. cereus with MIC value 0.7 μg/ml. Moreover, the antioxidant potential was determined via DPPH which showed strong radical scavenging activity of 88.3% and IC50 = 20.4 μg/mL. Additionally, the extract exhibited significant anticancer activity against A549 lung cancer cells, with an IC50 value of 15.57 ± 0.27 µg/mL, while showing minimal toxicity toward normal Wi38 cells (IC50 = 37.71 ± 0.31 µg/mL). GC-MS investigation of S. armeniacus crude extract exhibiting antimicrobial, antioxidant, and anticancer related bioactive compounds such as (Di-tert-butylhydroquinone, 4-Aminocyclohexanecarboxylic acid) and various fatty acids namely (stearic acid, palmitic acid, Ethanedioic acid, and Butanedioic acid). These results highlight the biological activity of S. armeniacus and emphasizing its potential as a unique source of bioactive molecules for biotechnological and therapeutic applications.

Mangrove ecosystems are remarkable coastal environments that thrive at the interface between land and sea, playing a crucial role in maintaining ecological balance and safeguarding coastal agricultural and fisheries productivity through erosion control, nutrient cycling, and salinity buffering. The physicochemical properties of mangrove soils underpin the health of these ecosystems, particularly for Avicennia marina, a keystone species critical to coastal resilience and habitat provisioning. However, anthropogenic disturbances threaten their sustainability and compromise their ability to deliver vital ecosystem services. Soil samples from undisturbed (Southern Corniche, Jeddah) and disturbed (Masturah) mangrove sites were analyzed for physicochemical characteristics to assess potential anthropogenic impacts along Saudi Arabia’s Red Sea coast. From six locations (undisturbed: Jeddah, n=3; disturbed: Masturah, n=3) soil samples were analyzed for texture, pH, electrical conductivity (EC), total dissolved solids (TDS), water content (%WC), total nitrogen (TN), phosphorus (TP), organic carbon (TOC), macronutrients (Na+, Ca²+, Mg²+, K+), and cation exchange capacity (CEC). Undisturbed soils exhibited significantly higher moisture, TN, TP, and TOC—key indicators of nutrient retention and carbon sequestration capacity—while disturbed soils were more alkaline, a condition linked to diminished nutrient cycling and plant stress. Macronutrient distribution (Na+ > Mg²+ > Ca²+ > K+) remained consistent across sites, suggesting salinity-driven nutrient imbalances may limit mangrove recovery. These findings highlight how soil degradation in disturbed mangroves reduces their ability to stabilize sediments, mitigate saltwater intrusion, and sustain fisheries nurseries, directly impacting coastal communities. Moreover, these soil changes reduce mangrove capacity to buffer adjacent farmland from salinization and erosion, threatening agricultural productivity and undermining carbon sequestration goals central to climate mitigation. To enhance ecosystem resilience, we recommend the application of soil organic amendments and the strategic conservation of high-carbon mangrove zones, in alignment with Saudi Arabia’s Vision 2030 sustainability framework. This study highlights the critical importance of safeguarding mangrove soils as foundational natural infrastructure for climate adaptation and food security in arid coastal environments.

A new species of the gobiid genus Trimma is described from the Farasan Banks in the southeastern Red Sea. The new species is characterized by having a predorsal midline with 7–8 scales, the fifth pelvic-fin ray unbranched, cheek and opercle scaleless, all pectoral-fin rays unbranched, and a dorsal fin VI + I,7, without elongate spines. In life, the species is bright yellow throughout, with a distinctive yellow-green longitudinal band in the central third of the dorsal fins. The new species inhabits caves on exposed offshore reefs at depths between 15 and 30 m where it occurs in small groups of up to 10 individuals. The new species appears to be sister to T.winchi from the western Indian Ocean. We also present a multilocus phylogeny (COI, 16S, Ptr, S7I1), including all known Red Sea Trimma and 21 non-Red Sea species, and an expanded supermatrix tree with 93 species to place Red Sea endemism in broader context. This brings the total number of Trimma species known from the Red Sea to 10, with eight appearing to be endemic to the region. The high proportion of endemism in the genus is noteworthy, even for the Red Sea, which has one of the highest proportions of endemic reef fishes in the Indo-Pacific. Moreover, K2P distances in the two widespread species suggest they may also represent cryptic endemic species, but further analyses are needed. The new species is currently known only from the Farasan Banks region despite extensive sampling along the Saudi Arabian Red Sea coast.

Renewable energy sources are critical choices for achieving long-term energy security while minimizing the effects of climate change. Wind energy in Egypt has received attention, however, wind power potential is dependent on climatic factors such as wind speed and temperature. Therefore, the wind power plan must rely on an in-depth understanding of wind resource sensibility to climate change to guarantee its sustainability, thereby supporting wind plan and climate change strategy. Using GIS analysis, the effect of climate change has been estimated on wind power density by 2065 under the climate change RCP 8.5 scenario. Furthermore, some criteria, such as elevation, slope, road networks, protectorates, archeological sites, touristic sites, and grids, have been used to identify regions that would be suitable for wind projects. The results revealed that wind energy potential is expected to be vulnerable to climate change, reflected in a 1% decrease in regions with high wind power density. Even after considering the effect of climate change, the Suez Gulf region would be the most suitable. Projects can also be expanded to other suitable locations where there are no projects yet, such as the Sinai Peninsula and the Red Sea coast.

Vulnerability Assessment of the Climatic Changes Implications on the Egyptian Red Sea Coast Based on Physical and Socioeconomic Indices

Petrography and sulfur isotope geochemistry of middle Miocene evaporites on the active continental margin, Ras Banas Peninsula, Red Sea coast, Egypt

Utilization of gamma-irradiation for seawater desalination.

Octocorals, a globally distributed class of Cnidaria, inhabit a wide range of environments, from cold to tropical waters and from shallow to deep-sea ecosystems. In the Red Sea, studies on octocoral diversity have mostly been focused on the Gulf of Aqaba and selected families or genera. While these studies have revealed a remarkable richness and diversity of shallow-water species, mesophotic and deep-sea octocoral research remains limited in the region, in particular along the Saudi Arabian coast. Here, we provide a first comprehensive assessment of this group's genetic diversity across the basin's bathymetric and latitudinal gradients. Following six Red Sea oceanographic expeditions and various biodiversity surveys conducted between 2020 to 2023, we analysed a collection of 728 octocoral specimens sampled along 13 degrees of latitude in the Saudi Arabian Red Sea, from shallow-water reefs to deep-sea habitats. We combined morphological identification and sequencing of mitochondrial barcode markers (mtMutS and COI) to delimit lineages. Our integrated results revealed the occurrence of 26 families and 56 genera in the basin from 3 to 859 m of depth. While the description of new species was beyond the scope of this work, here we provide a reference dataset for octocoral diversity from a biodiversity hotspot, as well as essential insights to inform biodiversity management and planning of conservation measures, particularly relevant for the rapidly developing Saudi Arabian Red Sea coast.

Mangroves as a nature-based solution: potential impacts of climate change and community-based mitigation measures for grey mangrove (Avicennia marina) along the Egyptian Red Sea coast

Twenty-nine sediment samples were collected from Hurghada Bay, a highly impacted coastal area along the Northern Red Sea of Egypt, to evaluate environmental quality and human-induced effects on benthic ostracods. As potential bioindicators, benthic ostracods are highly responsive to environmental disturbances, with pollution leading to reduced abundance, lower diversity, and increased opportunistic taxa. To investigate the link between ostracod assemblages and sediment contamination, we measured the concentrations of eight heavy metals (Cu, Cd, Zn, Pb, As, Cr, Ni, and Mn) using inductively coupled plasma–atomic emission spectrometry (ICP-AES). Multivariate statistical analyses identified three distinct ostracod assemblages distributed across three station groups with varying pollution levels. Group I, associated with offshore stations, exhibited low to moderate heavy metal (HM) concentrations and high ostracod abundance and was dominated by Moosella striata, Hiltermannicythere rubrimaris, Ruggieria danielopoli, Neonesidea schulzi, and Paranesidea fracticorallcola, where the water depth and sand content are the main controlling factors. In contrast, Group II, corresponding to stations with the highest HMs and total organic matter (TOM), was dominated by pollution-tolerant species Jugosocythereis borchersi, Cyprideis torosa, Alocopocythere reticulata, and, to a lesser extent, Ghardaglaia triebeli, with reduced ostracod density and diversity. Group III, characterized by stations influenced by the mud-controlling factor, had the lowest HMs and was dominated by pollution-sensitive species Xestoleberis rhomboidei, Paranesidea fortificata, and Loxocorniculum ghardaquensis. These findings highlight the ecological risks posed by HM pollution and emphasize the urgent need for pollution mitigation strategies and continued monitoring to preserve the Red Sea’s benthic biodiversity.

A brooch found in a mid-first-century AD context at the Roman port of Berenike, on the Red Sea coast of Egypt, represents the southernmost find of an Aucissa-type fibula. The item reflects the identity of its wearer, possibly a Roman soldier, for whom it may have held sentimental value.

A new, brightly red-coloured, symbiotic hesionid worm, Parahesione dudahamra sp. nov., is described based on the holotype and single specimen collected in the shore waters of the King Abdullah University of Science and Technology, Thuwal, Red Sea coast of Saudi Arabia. The new species is characterized by simple lateral antennae without distinct ceratophores, longest dorsal cirri reaching chaetiger 12, and longest ventral cirri reaching only chaetiger 4. The holotype was extracted from a burrow of an unknown host in very shallow water, close to mangrove roots. The diversified burrowing fauna of the type locality, including the possible infaunal hosts of P. dudahamra sp. nov., is briefly discussed. In addition, a full description and ecological notes are provided for another hesionid worm, Leocrates giardi Gravier, 1900, of which several specimens were extracted from burrows at the type locality of P. dudahamra sp. nov.

The contamination due to coastal landfill is a growing environmental concern, particularly in fragile marine ecosystems, where leachate can mobilize toxic elements into soil, water, air, and sediment. This study aims to assess the impact of a coastal landfill in Al-Qunfudhah, western Saudi Arabia, on nearby coastal sediments by identifying the concentration, distribution, and ecological risk of potentially toxic elements (PTEs) using geospatial and multivariate analysis tools. The results indicate significant accumulation of Pb, Zn, Cu, and Fe, with Pb reaching alarming levels of up to 1160 mg/kg in the landfill area, compared to 120 mg/kg in the coastal sediments. Zn contamination also exhibited substantial elevation, with values reaching 278 mg/kg in landfill soil and 157 mg/kg in coastal sediment. The enrichment factor values indicate moderate to severe enrichment for Pb (up to 73.20) and Zn (up to 6.91), confirming anthropogenic influence. The contamination factor analysis categorized Pb contamination as very high (CF > 6), suggesting significant ecological risk. Comparison with sediment quality guidelines suggest that Pb, Zn, and Cu concentrations exceeded threshold effect levels (TEL) in some samples, posing potential risks to marine organisms. The spatial distribution maps revealed pollutant migration from the landfill toward the coastal zone, emphasizing the necessity of monitoring and mitigation strategies. As the first comprehensive study on landfill-induced PTEs contamination in Al-Qunfudhah, these findings provide essential insights for environmental management and pollution control policies along the Red Sea coast.

This study presents original data on the winter avifauna of Egypt, based on fieldwork conducted between 2 and 8 February 2022. The research covered over 800 km and included four ecoregions: the Red Sea coastal desert, North Saharan steppe and woodlands, the flooded savannas of the Nile Delta, and the Sahara Desert. Observations were made in natural, agricultural, mountainous, and urban habitats. Data were collected using 12× binoculars and a Canon telephoto camera with GPS-coordinated images via ViewRanger. The collected geodata were analysed in QGIS, and species identification was supported by field guides on North African birds. A total of 41 bird species were recorded: 29 non-passerines and 12 passerines. Notable observations included the early breeding behaviour of the brown-necked raven (Corvus ruficollis) in the Etbai Mountains and a nest of the black-winged kite (Elanus caeruleus) on a date palm in the Nile Valley. Two adult lesser spotted eagles (Clanga pomarina) flying north above Hurghada indicated the onset of spring migration. The Red Sea coast hosted numerous gulls and terns, such as Larus armenicus, Chroicocephalus genei, Ichthyaetus hemprichii, Ichthyaetus leucophthalmus, and Thalasseus bengalensis. Species like the western cattle egret (Bubulcus ibis), white-throated kingfisher (Halcyon smyrnensis), and spur-winged lapwing (Vanellus spinosus) were abundant in agricultural zones of the Nile Valley. Several species of European origin, including Gallinula chloropus, Ardeola ralloides, and Chroicocephalus ridibundus, were recorded wintering in this region. Synanthropic species such as Passer domesticus, Spilopelia senegalensis, and Corvus cornix were found nesting within hotel areas and urban gardens. The presence of the Sardinian warbler (Curruca melanocephala) in the coastal green zone suggests possible breeding activity in quasi-natural shrubby habitats. The study demonstrates the ecological importance of Egypt’s varied habitats for both Afrotropical residents and Eurasian migrants during winter, emphasising the country’s role in transcontinental avian ecology and contributing crucial data to underrepresented seasonal periods.

Abstract Marine and coastal ecosystems have been undergoing dramatic shifts due to global environmental changes. The rise in seawater temperature, ocean acidification, hypoxia, eutrophication, and anthropogenic pollution severely affects marine organisms. There is an urgent need to better understand the influence of such disturbances on the physiology and life cycles of marine organisms. However, conducting controlled laboratory experiments often requires many replicates and information on individual origin, age, and genetic diversity. The availability of tropical model organisms is limited. Large‐scale sampling efforts from wild communities may negatively impact local biodiversity, especially in coral‐reef regions under threat. In this study, we present new methodologies for cultivating the tropical‐origin ascidian (phylum: Chordata, class: Ascidiacea) Phallusia nigra in both closed and open water facilities, demonstrating feasibility to produce viable populations of juvenile P. nigra originating from the South China Sea (Singapore) and the Mediterranean and Red Sea coasts of Israel for research. In an open water system, P. nigra can be reared from eggs to adults for 11 months. Reproductive animals were obtained by the fourth month. As it is possible to rear individuals to maturity, long‐term and cross‐generational effect studies can also be explored. Finally, our work provides a method to produce a tropical model for biomedical research, which in regard to ascidians has so far been restricted to temperate cultivars. P. nigra offers fundamental opportunities for environmental research due to its wide global distribution, easy field sampling, and potential as a biological indicator species for anthropogenic pollution and global climate change.

This study identifies the optimal location for an offshore energy island to supply sustainable power to desalination plants along the Red Sea coast. As demand for clean energy in water production grows, integrating renewables into desalination systems becomes increasingly essential. A decision-making framework was developed to assess site feasibility based on renewable energy potential (solar, wind, and wave), marine traffic, site suitability, planned developments, and proximity to desalination facilities. Data was sourced from platforms such as Windguru and RETScreen, and spatial analysis was conducted using Inverse Distance Weighting (IDW) and Multi-Criteria Decision Analysis (MCDA). Results indicate that the central Red Sea region offers the most favorable conditions, combining high renewable resource availability with existing infrastructure. The estimated regional desalination energy demand of 2.1 million kW can be met using available renewable sources. Integrating these sources is expected to reduce local CO2 emissions by up to 43.17% and global desalination-related emissions by 9.5%. Spatial constraints for offshore installations were also identified, with land-based solar energy proposed as a complementary solution. The study underscores the need for further research into wave energy potential in the Red Sea, due to limited real-time data and the absence of a dedicated wave energy atlas.

The ongoing conflict in Yemen, which began in 2014, has led to one of the world's most severe humanitarian crises. The Hudaydah region, located on the Red Sea coast and home to the country's second-largest port, is critical for the delivery of food and medical supplies. We conducted a two-stage cluster randomised survey to estimate the prevalence of acute malnutrition among children and pregnant and lactating women (PLW). We estimated the prevalence of household food insecurity and quantified death rates. During February-March 2021, acute malnutrition prevalence was 14.1%(95%CI: 12.2-16.2) among children aged 6-59 months, with 4.0%(95%CI: 3.3-4.9) severely malnourished. 43% of malnourished children were not in a nutritional programme. Acute malnutrition among PLW was 25.7%(95%CI: 23.0-28.6). We estimated 54%(95%CI: 44-63) of households were food insecure, 22%(95%CI: 15-31) severely. Crude and under-five death rates were below humanitarian thresholds. More than half of the children reported sickness in the last 14 days, and this proportion was higher among the malnourished.