Red Sea Coast Research Articles

Antimicrobial and Antioxidant Activities of Some Selected Seaweeds Species from the Western Coast of the Northern Egyptian Red Sea

Antimicrobial and Antioxidant Activities of Some Selected Seaweeds Species from the Western Coast of the Northern Egyptian Red Sea

The Morphological Characterization of the Abundant Amphipods Associated with Cystoseira crinita Duby, 1830: A Case Study from the Northwestern Red Sea Coast, Egypt

The Morphological Characterization of the Abundant Amphipods Associated with Cystoseira crinita Duby, 1830: A Case Study from the Northwestern Red Sea Coast, Egypt

Biomass Carbon Stock and Carbon Sequestration Potentiality in Mangrove Ecosystem along the Egyptian Red Sea Coast

Biomass Carbon Stock and Carbon Sequestration Potentiality in Mangrove Ecosystem along the Egyptian Red Sea Coast

Occurrence, distribution, and composition of black sand along the Red Sea, Egypt

Black sand along the Red Sea is often composed of volcanic minerals and heavy minerals. The Red Sea region is known for its unique geological features, and black sand beaches can be found in various areas along its shores. The study presents a comprehensive semi-quantitative chemical analysis of black sand samples collected from various locations along the red sea, revealing significant variations in their elemental compositions. The main oxides were identified in each sample, determined through X-ray diffraction (XRD) and X-ray fluorescence (XRF) analyses, indicate diverse mineralogical compositions. The spatial distribution of minerals at each site is depicted through mapping. Additionally, Fourier-transform infrared (FTIR) spectra offer information on the functional groups present in the samples, revealing the existence of hydroxyl groups, aliphatic compounds, and adsorbed water molecules. For Qusier-Elsharm Alqbly, Safaga, Marsa Alam, Gabal Alrosass, Hurghada Titanic, Hurghada Elahiaa, Gemsa, and Ras Elbehar samples, the results highlight the presence of various minerals, such as Quartz, Calcite, Titanium Dioxide, Magnetite, Hematite, Aluminum Oxide, Zirconium Dioxide, Chromium (III) Oxide, and others, providing insights into the geological characteristics of each location. The differences in mineral content among the examined sites are linked to the geological and mineralogical makeup of the source rocks upstream and midstream in the basins that discharge into the surveyed regions. So, variations in black sand concentrations among different locations offer insights into the geological and mineralogical diversity of the studied areas along the Red Sea coast. This study addresses the existing knowledge gap by focusing on the preliminary exploration and description of the occurrence, distribution, and composition of black sand along the Red Sea in Egypt. whereas the results provide valuable insights into the geological diversity of black sand deposits in the surveyed areas, underscoring the need for additional research and interpretation of these variations. Therefore, the in-depth examination of mineralogical composition and crystal structures establishes a foundation for future investigations in the field of geology and earth sciences.

Depositional mechanism of Duwi Formation organic-rich rocks in anoxic Campanian-early Maastrichtian condensed sections in the Qusseir–Safaga region in Eastern Desert of Egypt and their economic importance

The organic-rich rocks of the Duwi Formation have gained much attention in recent years because of the growing demand for their utilization as energy and metal sources. A depositional model for these important rocks is delineated in the present study based on multiple analytical approaches. Samples from these organic-rich rocks were collected from eight mines in the Qusseir-Safaga region along the Red Sea coast in the Eastern Desert of Egypt. These mines are located at El Nakheil, Younis, El Beida, Atshan, Hamadat, Tundub Bahri, Tundub Qubli, and Zog EL Bahr. The depositional model is based firstly on organic geochemical and petrographical analyses of the organic matter to identify its enrichment, composition, hydrocarbon potential, types and origin, and their relationship to rock minerals. Secondly, the inorganic geochemical analysis, including mineralogy and trace elements, is integrated to explore the lithological characteristics and to confirm the results obtained from other analyses. Only the El Nakheil, Atshan, Tundub Bahri, and Tundub Qubli mines are found to have total organic carbon content above 10 wt%. These mines contain hydrogen-rich organic matter that reached a maximum in the El Nakheil Mine as reflected in the Rock-Eval parameters of S2 (137.95 mg HC/g rock) and hydrogen index (HI of 707 mg HC/g TOC). The organic matter is composed mainly of large sheet-like alginite particles and prasinophytes that are finely laminated with minerals, planktonic debris of fish bones, and foraminifera without any sign of the presence of benthic organisms or bioturbation. This lamination is attributed to the occurrence of condensed sections in the studied mines. In addition, the high organic enrichment in terms of quantity and quality is accompanied by enriched metal composition including trace elements that signify anoxic conditions and low sedimentation rates. This composition points to the occurrence of prominent anoxic conditions that are stabilized by a slow sea level rise, which inhibits water circulation and water column stagnation in a restricted basin. The depositional model emphasizes the optimal balance between anoxia, sedimentation rate, and paleoproductivity that resulted in enhanced organic matter preservation in a condensed section. The deposition of the organic-rich rocks is situated in the deep parts of the basin or depocenters that reached their present-day distribution by topographic inversion. The organic and metalliferous reserves in these organic-rich sediments are calculated in the studied mines. The estimation of these reserves is found to be economic for many trace metals in an ore reserve that reached 151742 tons in one bed alone within the Duwi Formation.

Exploration and identification of ancient Roman shipwreck located at Quseir, Red Sea

Recent marine geophysical investigations in front of the Myos Hormos Port (also known as Quseir al-Qadim) on the Red Sea coast of Egypt indicated the existence of an ancient Roman shipwreck, among other features on the seafloor. The study showed that side scan sonar imaging is a powerful technique for classifying the seafloor and detecting submerged targets among other seafloor features with resembling acoustic signatures. Integrating bathymetric data with sonar imageries displayed the seafloor topography in front of the ancient port where reef habitats were dominant. The Autonomous Underwater Vehicle was efficient in mapping closed and near-shore areas like bays. This vehicle provided high-resolution bathymetric and sonar data for the semi-closed bay area located at the entrance of the ancient port. Acoustic measurements were done for the sunken shipwreck using sonar software, and a structural model was established for the ∼ 32 m long sunken ship. The model suggested the presence of a pile of shipload gathered around the shipwreck. Results can contribute to the development of Egypt's tourism industry by promoting underwater cultural heritage preservation, as the discovery of an ancient Roman shipwreck is a significant finding that can attract tourists worldwide.

Innovative approach for predicting daily reference evapotranspiration using improved shallow and deep learning models in a coastal region: A comparative study

Accurate and reliable estimation of Reference Evapotranspiration (ETo) is crucial for water resources management, hydrological processes, and agricultural production. The FAO-56 Penman-Monteith (FAO-56PM) approach is recommended as the standard model for ETo estimation; nevertheless, the absence of comprehensive meteorological variables at many global locations frequently restricts its implementation. This study compares shallow learning (SL) and deep learning (DL) models for estimating daily ETo against the FAO-56PM approach based on various statistic metrics and graphic tool over a coastal Red Sea region, Sudan. A novel approach of the SL model, the Catboost Regressor (CBR) and three DL models: 1D-Convolutional Neural Networks (1D-CNN), Long Short-Term Memory (LSTM), and Gated Recurrent Unit (GRU) were adopted and coupled with a semi-supervised pseudo-labeling (PL) technique. Six scenarios were developed regarding different input combinations of meteorological variables such as air temperature (Tmin, Tmax, and Tmean), wind speed (U2), relative humidity (RH), sunshine hours duration (SSH), net radiation (Rn), and saturation vapor pressure deficit (es-ea). The results showed that the PL technique reduced the systematic error of SL and DL models during training for all the scenarios. The input combination of Tmin, Tmax, Tmean, and RH reflected higher performance than other combinations for all employed models. The CBR-PL model demonstrated good generalization abilities to predict daily ETo and was the overall superior model in the testing phase according to prediction accuracy, stability analysis, and less computation cost compared to DL models. Thus, the relatively simple CBR-PL model is highly recommended as a promising tool for predicting daily ETo in coastal regions worldwide which have limited climate data.

Land use and land cover mapping using Landsat-8 and Sentinel-2 data in Al Qunfudhah coast, western Saudi Arabia: A comparative study

Al Qunfudhah Governorate has assumed a tourist status in the strip of Saudi coastal cities on the Red Sea coast. Agriculture, food industries, and engineering industries are among the most important economic activities in the city. As a result, Land use and land cover (LULC) detection is essential for several reasons: urban planning, sustainability, resource management and environmental preservation. This research aims to identify the LULC of the Al Qunfudhah area in western Saudi Arabia by comparing Landsat-8 and Sentinel-2 data outputs and evaluating their accuracy results. Various methods are used to process satellite image data to enhance the contrast between surface features. Some of these techniques are true colour composite (TCC) images, enhanced true colour composite (ETCC) images, false colour composite (FCC) images, principal component analysis (PCA), band ratios and Maximum Likelihood Algorithm (MLA) Supervised Classification. By utilising band combination methods, PCA methods, and band ratio methods, we were able to map a variety of features, including vegetation cover, mangroves, Sabkha and non-Sabkha deposits, wadi basins, shallow and deep shelf areas, islands, sand and mud sediments, rocky reefs and urban areas. As part of the study, ArcGIS 10.8's supervised classification tool was employed to categorise the study region's features and calculate the percentage of each class. In both Landat-8 and Sentinel-2 classification images, the same classes were identified (i.e. sand and mud sediments, sabkhas, wadi basins, aeolian sand and loess sediments, islands, urban areas, vegetation, and mangroves). The accuracy of the classification results was determined using a reliable statistical approach. The accuracy assessments of Landsat-8 and Sentinel-2 revealed accuracy rates of 87% and 89.1% respectively, along with kappa coefficients of 84.9% and 87.3%. For the investigated area, the Landsat-8 and Sentinel-2 satellites were effective in producing LULC maps.

Landslide susceptibility assessment along the Red Sea Coast in Egypt, based on multi-criteria spatial analysis and GIS techniques

The Egyptian Red Sea coast, a mountainous coastal region, is periodically exposed to landslide that cause severe man and economic losses. That is due to its geological, hydrogeomorphological, and seismological nature. This research aims to map landslide susceptibility in the study area using a multi-criteria overlay analysis approach. Slopes, elevations, aspects, curvature, lineaments, faults, earthquakes, rainfall, stream network, and rock units are the factors used to derive the landslide's susceptibility map. The data were obtained from research organizations and open-source geospatial platforms. The landslide susceptibility map of the area under investigation ranges from low to high as follows: 1) low (23 %), 2) moderate (43 %), and 3) high (34 %) from total area. The used model is validated using direct field check and statistical analysis by Receiver operating characteristic (ROC) curve test 40 landslides events. Based on ROC, the multi-criteria overlay analysis approach can predict landslides by 82 % at a 95 % confidence level. The leading causes of landslides are geological, topographical, hydrogeomorphological, and seismological. For long-term development, the study's findings would assist decision-makers in lowering the risks connected with landslides in the areas. To reduce the chance of landslides, the study recommended it is important to take into account the rugged topography of zones where landslides are likely to occur and implement rockfall protection systems like barriers, embankments, or mesh.

Increase in dengue fever in travellers returning from Egypt, Germany 2023.

Dengue virus (DENV) infections after exposure in Egypt increased in Germany in 2023, with 36 cases vs zero to eight in 2017 to 2022. Over 90% of the patients had stayed on the Red Sea Coast (mostly Hurghada), almost 50% in private residences. Case numbers increased more strongly than traveller numbers. Mosquito control is more difficult in towns than hotel grounds, increasing the risk of infection at private residences. Physicians should consider dengue for unexplained fever after return from Egypt.

An attempt to calculate the curie point in the Eastern part of Egypt

A curie point depth (CPD) map of the selected area in Egypt (Safaga–Hurghada area along the Red Sea coast), was constructed from the spectral analysis of aeromagnetic data. It was chosen there because the Red Sea and the Gulf of Suez coasts are considered as two of the highest temperature geothermal potential in Egypt. The CPD values were estimated from 10 overlapping blocks, 90 × 90 km in size, using band-pass filtered of aeromagnetic data. The Curie point depth was calculated. The CPD for the region ranges between 26.69 km and 42.69 km.A corresponding heat flow map was also generated from CPD and thermal gradient estimation. The boundaries between the zones of the shallow and deep CPD's coincide well with faults trending NW direction (more or less parallel to the Red Sea) and NE direction. Deepening of CPD's (low heat flows) was detected in two parts, the first one at the northern part of the study area (NW part of Ras Gemsa region). The second, at the southern part (east of Qena).

Assessment of heavy metals at mangrove ecosystem, applying multiple approaches using in-situ and remote sensing techniques, Red Sea, Egypt.

Mangrove areas are considered the most retention zone for heavy metal pollution as it work as an edge that aggregates land and sea sediments. This study aims to examine if the heavy metals' existence in the mangrove sediment is related to contamination or natural resources. In addition, it gives an interpretation of the origin of these metals along the Egyptian Red Sea coast. Twenty-two samples of mangrove sediments were collected and then, analyzed for metals (Mn, Ni, Cu, Fe, Cd, Ag, and Pb) using inductively coupled plasma mass spectroscopy (ICP-MS). Integration between the in-situ data, contamination indices, and remote sensing and geographical information science (GIS), and multivariate statistical analysis techniques (PCA) were analyzed to assess and clarify the spatial origin of heavy metals in sediment at a regional scale. The average concentration of heavy metals from mangrove sediments were shown to be substantially lower than the referenced value, ranging from moderate to significant except the levels of Ag were very high. The heavy metals concentrations were expected to be naturally origin rather than anthropogenic and that be confirmed by mapping of Red Sea alteration zones spots. These alteration zones are parallel to mangrove sites and rich by several mineralization types including heavy metals that are carried by flooding to the coastline. Remote sensing and GIS techniques successfully contributed to interpreting the pattern of the origin of heavy metals and discharging systems that control the heavy metals concentration along the Red Sea coast.

Occurrence, Distribution, and Sources of Aliphatic and Cyclic Hydrocarbons in Sediments from Two Different Lagoons along the Red Sea Coast of Saudi Arabia

Surface sediment samples from Al-Qahma lagoon in the southern part and Al-Wajh lagoon in the northern part of the Red Sea coast of Saudi Arabia were collected by a Van Veen grab sampler to determine the characteristics, distribution, and sources of aliphatic and cyclic hydrocarbons. The total extractable organic matter (TEOM) was extracted with a dichloromethane/methanol mixture after drying and sieving the sediments and identified by gas chromatography–mass spectrometry. The TEOM comprised n-alkanes (302.6 ± 446.7 ng·g−1 and 64 ± 50 ng·g−1), hopanes (29.8 ± 132.3 ng·g−1 and 1.0 ± 2.5 ng·g−1), steranes (0.0 and traces), n-alkanoic acids (745.8 ± 799.6 ng·g−1 and 120.7 ± 92.0 ng·g−1), n-alkanols (457.4 ± 1085.6 ng·g−1 and 49.7 ± 32.3 ng·g−1), polycyclic aromatic hydrocarbons (PAHs) (54.5 ± 96.8 ng·g−1 and 7.8 ± 8.5 ng·g−1), and phthalates (185.3 ± 169.9 ng·g−1 and 67.4 ± 70.4 ng·g−1) in the Al-Qahma and Al-Wajh lagoon sediments, respectively. The percentages of the various sources relative to total aliphatic and cyclic hydrocarbon concentrations were 6.9 ± 6% for terrestrial plants, 53.7 ± 19% for algae, 10 ± 2% for microbial, 16 ± 12% for petroleum, and 13.4 ± 7 for plasticizer inputs in Al-Qahma lagoon. In Al-Wajh lagoon, they were 9.7 ± 4% for terrestrial plants, 30.8 ± 14% for algae, 25.2 ± 5% for bacteria, 11.2 ± 3% for petroleum, and 23.1 ± 11% for plasticizers.

Nesting Distribution and Conservation of the Brown Booby (Sula leucogaster) on the Red Sea Coast of Saudi Arabia

Nesting Distribution and Conservation of the Brown Booby (Sula leucogaster) on the Red Sea Coast of Saudi Arabia

Statistical Downscaling of Surface Air Temperature Projection over the Egyptian Red Sea Coast

Statistical Downscaling of Surface Air Temperature Projection over the Egyptian Red Sea Coast

Environmental Assessment of Heavy Metals in Coastal Water of Suez Bay, Northern Red Sea Coast

Environmental Assessment of Heavy Metals in Coastal Water of Suez Bay, Northern Red Sea Coast

Levels, spatial distributions, and provision of petroleum hydrocarbons and phthalates in sediments from Obhur lagoon, Red Sea coast of Saudi Arabia.

The levels, spatial distribution, and sources of petroleum hydrocarbons and phthalates were assessed in surface sediment samples from the urban lagoon of Obhur near Jeddah, the largest city on the Red Sea coast of Saudi Arabia. The lagoon was divided into the inner zone, middle zone, and outer zone based on its geomorphological features and developmental activities. n-Alkanes, hopane and sterane biomarkers, and unresolved complex mixture were the major petroleum hydrocarbon compounds of the total extractable organic matter. Phthalates were also measured in the sediment samples. In the three zones, n-alkanes ranged from 89.3 ± 88.5 to 103.2 ± 114.9ng/g, whereas the hopane and sterane biomarkers varied from 69.4 ± 75.3 to 77.7 ± 69.9ng/g and 72.5 ± 77.9-89.5 ± 82.2ng/g, respectively. The UCM concentrations ranged from 821 ± 1119 to 1297 ± 1684ng/g and phthalates from 37.4 ± 34.5 65 ± 68ng/g. The primary origins of these anthropogenic hydrocarbons in the lagoon sediments were petroleum products (boat engine discharges, boat washing, lubricants, and wastewater flows) and plasticizers (plastic waste and litter). The proportions of anthropogenic hydrocarbons derived from petroleum products in the sediment's TEOM ranged from 43 ± 33 to 62 ± 15%, while the percentages for plasticizers varied from 2.9 ± 1.2 to 4.0 ± 1.6%. The presence and inputs of these contaminants from petroleum and plastic wastes in the lagoon's sediments will eventually have an impact on its habitats, including the benthic nursery and spawning areas.

New occurrence of Cirolana capricornica (Isopoda: Cirolanidae) from Epinepheluschlorostigma in Suez Governorate, Egypt.

The isopods of the Crustacea are noteworthy. All marine, fresh, and brackish waterways at all depths are home to aquatic organisms. This order also includes species that live on land. This study aimed to report a new occurrence of the isopod Cirolana capricornica on the operculum, mouth, and body cavities of Epinephilus chlorostigma in the Suez Governorate, Egypt. With the help of fishermen, 50 live E. chlorostigma (Linnaeus, 1758) were randomly gathered along the Red Sea coast of the Suez Governorate during November and December 2019 for the current investigation. Isopods were isolated from the fish samples and captured using light and electron microscopy for morphological identification. Some fish were emaciated, and minute white isopods were attached externally to the skin near the gills and mouth cavity, and internally to the mouth cavity. No correlation was observed between body cavity attachment and gross lesions. The prevalence of infestation was 16%. C. capricornica was identified using optical and electron microscopy to analyze the isopod specimens' morphology. This scavenging isopod species is newly discovered in Egypt.

PRESERVING AND SUSTAINING THE ENVIRONMENTAL IDENTITY OF ISLAMIC RESIDENTIAL BUILDINGS IN THE HEJAZ REGION IN KSA

The Kingdom of Saudi Arabia has a rich urban and architectural legacy that dates back to the numerous eras of Islamic civilization. This study investigates the environmental influence on Ottoman-style heritage structures in the Kingdom of Saudi Arabia, particularly in the Hejaz Region. The region was chosen because of its diverse climates, which include a hot, dry environment in the middle of the Western Desert and a hot, humid climate on the Red Sea coast. Heritage buildings are examined from design, architectural, and urban perspectives to learn how environmental sustainability is achieved and to examine building materials and their sustainability. Furthermore, common architectural characteristics, systems, and designs are recognized to be integrated into modern building design for the contemporary era to maintain their design uniqueness.

Environmental implications of illegal heavy metal mining in the Shalten area, Egypt’s Eastern Desert

ABSTRACT Most of Africa’s illegal mining operations are conducted in rural areas, but along the Red Sea coast, they primarily occur in the Eastern Desert, where they are regarded as the major source of revenue. Soil samples were collected and examined at an illegal gold mining site in the far south of Egypt’s Eastern Desert to determine the toxicity levels of eight heavy metals for pollution load index (PLI), Igeo, and health (Au, Ag, As, Hg, Ni, Cr, Zn, and Pb). The methodology used in this study was categorized into fieldwork with restricted rules within the visit, soil samples collected from the field, chemical analyses for heavy metals, and statistical analyses by applying six equations to define the environmental status of the study area. It was found that the PLI increases contamination as an environmental risk grade, Igeo, reaches grade 6, which is highly contaminated, and the average hazard index (HI) for the individual elements is high (>0.01). The health risk assessment results for Ni and Cr showed that oral intake was the main mode of exposure to heavy metals in the tailings of illegal mines. In addition, the average levels of As, Hg, Cr, Ni, Pb, and Zn were higher than the equivalent background levels for soils. Thus, adult cancer risk (CR) exceeds the permissible level of 10−4. The illicit mining activities in the Eastern Desert also resulted in heavy metal contamination with substantial noncarcinogenic hazards for As and Zn, necessitating urgent remediation.