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1

Investigating the role of atmospheric variables on sea level variations in the Eastern Central Red Sea using an artificial neural network approach

100%
Zubier K. M., Eyouni L. S.
Oceanologia
|
2020
|
tom 62
|
nr 3
2
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Recent sea surface temperature trends and future scenarios for the Red Sea

100%
Shaltout M.
Oceanologia
|
2019
|
tom 61
|
nr 4
3
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Heavy metals contamination and distribution of benthic foraminifera from the Red Sea coastal area, Jeddah, Saudi Arabia

100%
Youssef M.
Oceanologia
|
2015
|
tom 57
|
nr 3
4

Trematodes from Red Sea fishes: Gibsonius aegyptensis gen.nov., sp.nov. [Lepocreadiidae Odhner, 1905] and Helicometra interrupta sp.nov. [Opecoelidae Ozaki, 1925]

100%
Hassanine R. M. E.-S.
Acta Parasitologica
|
2005
|
tom 50
|
nr 4
Specimens of the marine fishes Rhabdosargus haffara (Sparidae) and Cociella crocodilo (Platycephalidae) were caught in the Red Sea off the coast of Sharm El-Sheikh, South Sinai, Egypt. Eight (20%) and 15 (43%) of these fishes, respectively, were found to harbour intestinal trematodes. R. haffara was parasitised by Gibsonius aegyptensis gen. nov., sp. nov. (Lepocreadiidae) and C. crocodilo by Helicometra interrupta sp. nov. (Opecoelidae). Gibsonius is similar to Myzoxenus Manter, 1934 and Diploproctia Mamaev, 1970 in having a ventral sucker with two longitudinal lips of a lamellar nature at its aperture, but differs greatly from each in other features: from Myzoxenus in having tegumental spines heavily distributed throughout the entire body surface, symmetrically arranged testes, a cirrus sac extending well posterior to the ventral sucker, a median genital pore, and vitelline follicles terminating posteriorly at the testicular level; and from Diploproctia in having an oval body, intestinal caeca which end blindly near the posterior extremity, a median genital pore between the intestinal bifurcation and ventral sucker, a pretesticular unlobed ovary, a uterus mainly situated dextral to the ovary, and vitelline follicles terminating posteriorly at the testicular level. Helicometra interrupta sp. nov. is similar to H. equilata, H. nasae and H. pteroisi in having a short fore- body and a long cirrus sac extending posterior to the ventral sucker, but differs significantly in having a shorter forebody (about 10% of body length), a curved cirrus sac extending posteriorly to a third of the distance between the ventral sucker and the ovary, vitelline follicles which terminate anteriorly at considerable distance posterior to ventral sucker and which are distinctly interrupted twice in the pre-testicular region, and smaller eggs.
5
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Circulation and winter deep-water formation in the Northern Red Sea

100%
Manasrah R., Badran M., Lass H. U., Fennel W.
Oceanologia
|
2004
|
tom 46
|
nr 1
Water mass characteristics and circulation patterns in the Gulf of Aqaba and northern Red Sea were studied for the first time during the r/v ‘Meteor’ cruise leg 44/2 from February 21st to March 7th 1999 using temperature-salinity profiles and current observations. The deep water in the northern Red Sea had similar characteristics to the well-mixed upper 450 m of water in the Gulf of Aqaba. This indicates that the winter mixed waters of the Gulf of Aqaba contribute significantly to deep-water in the northern Red Sea. Mixing in the Gulf of Aqaba is an annually repeated event that starts with the cooling of the surface water during November–December and reaches a maximum, which in most years extends down the entire water column in March–April. Waters deeper than the mixed layer in the Gulf seems to be rather passive and play no specific role in water mass formation in the northern Red Sea. In contrast to the Gulf of Aqaba, the upper 200 m of the northern Red Sea were stratified (21.5–23.5◦C, and 40.0–40.3 PSU). Stratification at the Strait of Tiran was weak (21.6–22.0◦C, and 40.3–40.5 PSU) and disappeared abruptly in the Gulf of Aqaba (21.4–21.6◦C, and 40.6–40.7 PSU). A well-developed cyclonic gyre with a diameter of about 50–60 km and maximum velocity of about 0.4 m s−1 was observed in the stratified upper 200 m of the northern Red Sea waters. The gyre may contribute to the preconditioning for intermediate water formation in the northern Red Sea.
6
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Relationships between water temperature, nutrients and dissolved oxygen in the Northern Gulf of Aqaba, Red Sea

100%
Manasrah R., Raheed M., Badran M. I.
Oceanologia
|
2006
|
tom 48
|
nr 2
Five years (1998, 2000–2003) of summer records of temperature, nutrients and dissolved oxygen concentrations in the upper 400 m of the water column of the northern Gulf of Aqaba were employed to produce a simple statistical model of the relationship between temperature versus nitrate, phosphate, silicate andd issolved oxygen concentrations. Temperature profiles in the upper 400 m during summer revealeda clear thermocline in the upper 200 m. This was reflected in nutrient ando xygen concentrations as nitrate, phosphate, and silicate increasedfr om the surface to deep water while dissolved oxygen decreased. The best fit relationship between temperature versus nitrate andphosphate was inverse linear and the best fit correlation between temperature versus silicate andd issolvedo xygen was fractional. The observedn utrient concentrations were shaped by a combination of the hydrodynamics and biological factors. Deep winter mixing and high nutrient concentrations dominate during winter. Shortly after the water stratifies in spring, the nutrients are drawn down by phytoplankton during the spring bloom and remain low throughout the rest of the year. The regression equations presented here will be useful in estimating nutrient concentrations from temperature records as long as the annual natural cycle is the main driver of nutrient concentrations and external inputs are insignificant. Deviations from these relationships in the future could provide insight into modifications in the nutrient concentrations probably resulting from new nutrient sources, such as anthropogenic inputs.
7
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Mineralogical and chemical composition of the mud fraction from the surface sediments of Sharm Al-Kharrar, a Red Sea coastal lagoon

84%
Basaham A. S.
Oceanologia
|
2008
|
tom 50
|
nr 4
557-575
Interaction between continental and marine end-members gives rise to the natural biogeochemical processes in Sharm Al-Kharrar, a lagoon in the arid Red Sea region. Twenty-nine surface sediment samples were collected from the area and their mud fraction analysed for grain size, OC, CaCO3, mineralogy and elemental composition. The mud fraction consisted of a mixture of siliciclastic/calcareous materials, dominated by silt size materials and characterised by low OC (average 0.71% ±0.13); CaCO3 varied widely, with an average of 45% ±18. Concentrations of Al, Fe, Mn, Cu, Ni, Cr, V and Ba showed a wide range of variation throughout the Sharm. The results were normalised to Al and subjected to cluster analysis in order to examine the relations between the mineralogy and the elemental composition. The contents of Al, Fe, Mn, Cu, Ni, Cr, V and Ba appeared to be influenced by the mixing of the two end-members in addition to the physiochemical processes associated with the mixing between episodic freshwater flooding and seawater. Zn was the single element that showed a slight departure from the mixing model.
8
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Evaluation of the carbon sequestration capacity of arid mangroves along nutrient availability and salinity gradients along the Red Sea coastline of Saudi Arabia

84%
Shaltout K. H., Ahmed M. T., Alrumman S. A., Ahmed D. A., Eid E. M.
Oceanologia
|
2020
|
tom 62
|
nr 1
9

Larval development and settlement of the barnacle Amphibalanus amphitrite from the Red Sea: Influence of the nauplii hatching season

84%
Al-Aidaroos A. M., Satheesh S.
Oceanological and Hydrobiological Studies
|
2014
|
tom 43
|
nr 2
10
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Effect of temperature on two reef-building corals Pocillopora damicornis and P. verrucosa in the Red Sea

84%
Al-Sofyani A. A., Floos Y. A. M.
Oceanologia
|
2013
|
tom 55
|
nr 4
11
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Spatial and temporal distribution of heavy metals in coastal core sediments from the Red Sea, Saudi Arabia

84%
Al-Mur B. A., Quicksall A. N., Al-Ansari A. M. A.
Oceanologia
|
2017
|
tom 59
|
nr 3
Jeddah is the most industrialized city on the west coast of Saudi Arabia and is under increasing influence of human activities. Heavy metals data were obtained from four near-coast Red Sea sediment cores in close proximity to Jeddah. Chromium, manganese, iron, copper, zinc, and lead were analyzed from depth-resolved sections of each core via heavy acid digestion and inductively coupled plasma-mass spectrometry (ICP-MS). The average concentrations of all four sites were 245.96 mg kg1, 478.45 mg kg1, 8506.13 mg kg1, 251.82 mg kg1, 623.09 mg kg1, and 362.75 mg kg1, respectively. The depth-resolved results showed that highest concentrations of Mn, Cu, and Pb were found in the top 15 cm of the core profile distributions compared to other depth sub-samples. Heavy metal concentrations in core sediments are increased near central Jeddah and have become higher in recent years. The results of enrichment factor calculations indicate little anthropogenic supply of Mn and Cr while Pb, Zn, and Cu show strong anthropogenic input. The Pollution Load Index was higher in the two sites closer to central Jeddah where power and desalination plants and wastewater release are known. This indicates that the area has suffered from heavy metal pollution compared to other non-industrialized sites in the Red Sea. Heavy metal contaminations due to anthropogenic activity should be taken into account to protect the Red Sea during future growth. The results of this work should be considered as a baseline for heavy metals monitoring in the sediments of the Red Sea coast near Jeddah, Saudi Arabia.
12
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Water column conditions in a coastal lagoon near Jeddah, Red Sea

84%
Albarakati A. M. A., Ahmad F.
Oceanologia
|
2012
|
tom 54
|
nr 4
13
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Distribution of the sea squirt Ecteinascidia thurstoni Herdman, 1890 (Ascidiacea: Perophoridae) along Suez Canal and Egyptian Red Sea coasts

84%
Gab-Alla A. A.-F. A.
Oceanologia
|
2008
|
tom 50
|
nr 2
239-253
Ecteinascidia thurstoni is a colonial sea squirt. It has a seasonal rhythm and a tropical and subtropical distribution; it is usually present during the summer months. It synthesizes a group of molecules called ecteinascidins. One of these is ET-743, a compound that has a most original anti-tumoral activity and is today considered to be one of the most promising substances effective against various solid-type tumors (currently sold under the trade name of Yondelis for the treatment of sarcomas and related tumors; it is undergoing phase II/III clinical trails for other kinds of tumors). Worldwide, Ecteinascidia species represent the only available source of this bioactive compound, which was first discovered in E. turbinata. During the present study, the ecology of E. thurstoni along the Suez Canal and Red Sea was investigated. Its populations were observed to be highly gregarious due in part to their low larval dispersal, which is very localized; larvae therefore tend to settle close to their parent colonies. It is only recorded in shallow waters (0.5–1.5 m) as an epiphyte on the pneumatophores of mangroves by the Red Sea, on the pilings of jetties, and the metal or cement banks of the Suez Canal. The morphometric characteristics (zooid length, zooid weight, colony weight) of the Suez Canal population differ significantly from those of the Red Sea. Studying the distribution of this species and locating its different populations along the Suez Canal and Red Sea could help to characterize their genetics, chemistry and bacterial communities at different isolated locations. Ultimately, this will help to define the sources of ET-743 and hence promote its biosynthesis on a commercial scale.
14
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Geochemical fractionation of heavy metals in sediments of the Red Sea, Saudi Arabia

84%
Al-Mur B. A.
Oceanologia
|
2020
|
tom 62
|
nr 1
15
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Characterization of the Northern Red Sea's oceanic features with remote sensing data and outputs from a global circulation model

84%
Eladawy A., Nadaoka K., Negm A., Abdel-Fattah S., Hanafy M., Shaltout M.
Oceanologia
|
2017
|
tom 59
|
nr 3
Sea surface temperature (SST) and surface wind (SW) are considered the most important components in air—sea interactions. This study examines the relationships between SST, SW and various oceanic variables in the northern Red Sea (NRS) during the period of 2000— 2014. The current study is the first attempt to identify the SST fronts and their relationship with the dominant circulation patterns. SST fronts are mapped using the Cayula and Cornillon algorithms. The analysis is performed with available remote sensing and reanalyzed data together with 1/128 HYbrid Coordinate Ocean Model (HYCOM) outputs. Seasonal-trend decomposition procedure based on loess (STL) is applied for trend analysis, and Principal Component Analysis (PCA) is run for the atmospheric parameters. The SST, SW speed and Chlorophyll-a (Chl-a) changes show insignificant trends during the period of 2000—2014. Meridional SST fronts are more significant during the month of January, and fronts that are perpendicular to the sea's axis occur from February to May. Distinct monthly and spatial variations are present in all the examined parameters, although these variations are less pronounced for the wind direction. The SST is mainly controlled by the air temperature and sea level pressure. Significant correlations exist between the SSTand the studied parameters (alongshore wind stress rather than the cross-shore wind stress, surface circulation, MLD, and Chl-a). Surface winds generally flow southeastward parallel to the Red Sea's axis explaining that alongshore wind stress is highly correlated with the studied parameters.
16
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Ecological assessment of heavy metals in the grey mangrove (Avicennia marina) and associated sediments along the Red Sea coast of Saudi Arabia

84%
Alzahrani D. A., Selim E.-M. M., El-Sherbiny M. M.
Oceanologia
|
2018
|
tom 60
|
nr 4
17
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Microfouling development on artificial substrates deployed in the central Red Sea

84%
Balgadi A. A., Salama A. J., Satheesh S.
Oceanologia
|
2018
|
tom 60
|
nr 2
18

Trematodes from Red Sea fishes: Pachycreadium lethrini sp.nov. [Opecoelidae Ozaki, 1925] and Pseudometadena aegyptensis sp.nov. [Cryptogonimidae Ward, 1917], with a review of their genera

84%
Hassanine R. M. E.-S.
Acta Parasitologica
|
2006
|
tom 51
|
nr 3
Specimens of the fishes Lethrinus nebulosus Forsskål (Lethrinidae) and Diplodus noct Valenciennes (Sparidae) were caught in the Red Sea off the coast of Sharm El-Sheikh, South Sinai, Egypt. Ten (33%) and 12 (24%) of these fishes, respectively, were found to harbour intestinal trematodes. L. nebulosus was parasitised by Pachycreadium lethrini sp. nov. (Opecoelidae) and D. noct by Pseudometadena aegyptensis sp. nov. (Cryptogonimidae). P. lethrini sp. nov. is unique in having distinctly unequal testes, contiguous gonads arranged obliquely in the right side of hindbody and a small egg size. However, it differs from each of the other three species of the genus in several other features: from P. gastrocotylum (Manter, 1940) Manter, 1954 in having a smaller sucker ratio and vitelline follicles terminating anteriorly at the level of intestinal bifurcation; from P. carnosum (Rudolphi, 1819) Cortini et Ferretti, 1959 in having a smaller body, a smaller sucker ratio, a genital pore situated ventrally to the anterior border of pharynx, a pretesticular ovary and vitelline follicles extending anteriorly to the level of intestinal bifurcation; and from P. lerneri Sogandares-Bernal, 1959 in having a larger body, a smaller sucker ratio and an unlobed ovary. P. angolensis Aleshkina et Gaevskaya, 1985 is considered an invalid species in Pachycreadium. P. aegyptensis sp. nov. is similar to P. celebesensis Yamaguti, 1952, but mainly differs in having a larger pharynx, a much shorter oesophagus, extensive vitelline acini and a shorter seminal vesicle. Pachycreadium Manter, 1954 and Pseudometadena Yamaguti, 1952 are briefly reviewed.
19

Ecological comments on the intestinal helminths of the rabbitfish Siganus rivulatus [Teleostei, Siganidae] from the Northern Red Sea

84%
Hassanine R. M. E.-S., Al-Jahdali M. O.
Acta Parasitologica
|
2007
|
tom 52
|
nr 3
Between May and September 2006, 640 specimens of the rabbitfish Siganus rivulatus Forsskål (Teleostei, Siganidae) were examined for infections with intestinal helminths. These fishes were caught in the Red Sea off the coast of Sharm El-Sheikh, South Sinai, Egypt, examined in a field laboratory and separated into three size groups of regular length intervals. Only three species of helminths were recovered: the trematode Gyliauchen volubilis Nagaty, 1956 (Gyliauchenidae Fukui, 1929), the acanthocephalan Sclerocollum rubrimaris Schmidt et Paperna, 1978 (Cavisomidae Meyer, 1932) and the nematode Procamallanus elatensis Fusco et Overstreet, 1979 (Cucullanidae Cobbold, 1864). The distribution of these helminths along the intestine of S. rivulatus, in all patterns of single and concurrent infections and the corresponding prevalences and intensities of infection in the different size groups of the fish were recorded. In single infections, each parasite species was found distributed in a well-defined fundamental niche along the intestine of Siganus rivulatus, and a distinct partial overlap between the niches of G. volubilis and Sclerocollum rubrimaris was observed. In concurrent infections with these two species, their fundamental niches were significantly reduced, probably being affected by interactive site segregation and individuals of each species were found segregated in a restricted realised niche. In all other patterns of concurrent infections, each parasite species was normally found in its original fundamental niche. The prevalences of these parasites in the fish examined were relatively low and somewhat similar. In all patterns of single and concurrent infections, the intensity of infection was directly related to fish size. In concurrent infection with G. volubilis and S. rubrimaris, a significant decline was observed in the intensities of both species in the different size groups of the fish, but, in all other patterns of concurrent infections, no significant change in intensity was observed. These observations suggest that the interaction between G. volubilis and S. rubrimaris is probably a negative and symmetrical one. The mode of transmission of these parasites to the fish is also discussed.
20

Intraspecific density-dependent effects on growth and fecundity of Diplosentis nudus [Harada, 1938] Pichelin et Cribb, 2001 [Acanthocephala, Cavisomidae]

84%
Hassanine R. M. E.-S., Al-Jahdali M. O.
Acta Parasitologica
|
2008
|
tom 53
|
nr 3
During June and July of 2007, a total of 130 specimens of the fish Rastrelliger kanagurta Cuvier (Teleostei, Scombridae), ranging between 19–31 cm in total length, were caught in the Red Sea off the coast of Sharm El-Sheikh, South Sinai, Egypt, and examined for infections by acanthocephalans (65 fish/month). Of this number, 29 (22.30%) were slightly or heavily parasitized by the acanthocephalan Diplosentis nudus (Harada, 1938) Pichelin et Cribb, 2001 (Cavisomidae); no other helminth parasites were found in the intestine of R. kanagurta. Twenty-nine infrapopulations of D. nudus, ranging from 23–218 individuals were collected from the infected fishes. These infrapopulations were distributed in a well-defined fundamental niche along the intestine of R. kanagurta, where the distribution of male worms was not random with respect to female worms size and position and suggests that the male-male competition for access to female may be intense and may select for large males. No correlation between fish size and infrapopulation size was observed. Correlations between female-to-male sex ratio and infrapopulation size, numbers of females and their mean lengths, numbers of males and their mean lengths, mean female length and mean male length within infrapopulation were very strong, and clearly suggest that as the infrapopulation size increased, the number of females and their mean lengths decreased and the number of males and their mean lengths increased. Combination of these results strongly suggests density-dependent effects and competition between male worms. The relationship between the mean female length or size and the number of eggs within its pseudocoel was strongly positive; egg production by female worm significantly decreases as the infrapopulation size increases, suggesting density-dependent reduction in female worm fecundity. Tendency for the variability in male testes size was not significant in infrapopulations of D. nudus. All of these results are discussed.
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