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1.
We undertook breeding surveys between 2010 and 2011 to assess the status of breeding birds on 16 islands in the northern Saudi Arabia. Sixteen bird species were found breeding at three different seasons; i.e. winter (Osprey), spring (Caspian and Saunder’s Terns), and summer (Lesser Crested, White-cheeked, Bridled Terns). It is postulated that food availability is an important factor influencing the breeding of seabirds in the northern Saudi Arabian Red Sea. Several species laid eggs earlier in northern parts of the Red Sea than in southern parts. The predicted increases in temperatures (Ta) could have a negative effect on species survival in the future, especially on those whose nests that are in the open. Finally, disturbance, predation and egg collection were probably the main immediate threats affecting the breeding seabird species in the northern Red Sea.  相似文献   

2.
Sea Urchin is not only the crucial keystone species for the coral reef restoration but also it has antimicrobial and anti-cancer activities. This study undertaken to focus on length weight relationship, size fecundity distribution and the estimation of fecundity from the long-spined Sea Urchin, Diadema savignyi at the coastal water of the middle Red Sea, Saudi Arabia. A total of 633 specimen of D. savignyi has been collected from the coastal water of Obhur Creak during the sampling time. In each species, total length (TL) measured as a TW = 11.908 × 0.9995 (R2 = 0.8975) through the linear regression graph and digital slide callipers and, individual body weight estimated by the digital balance. The natural and fishing mortality 2.02/yr and 0.19/yr respectively has documented from study area. The Asymptotic length value (L∞) (cm) were estimated 7.35 where the growth coefficient (K) was 0.67 from the monthly length-frequency numeric data by using FAO FISAT II software for generating and estimating the population parameters and age. However, the recruitment pattern was observed to be increased gradually with the maximum recruitment peak between the months of September and October 2021. Therefore, the estimation of fecundity varied from 49,226 ova (total length 3.1 cm) to 466,133 ova (total length 6.8). As a result, analysis of the relationship between the absolute fecundity (F) and total length (TL), and between the fecundity and drained body weight (DW), revealed a linear regression model with a positive and significant relationship at p < 0.05. This is the first approach to study the detailed population dynamic of the ecologically and economically important tropical long spine sea urchin (D. savignyi) endemic to the region. However, the result so far obtained from this research would greatly be useful towards the understanding of the detailed population structure and growth patterns that will undoubtedly help us to develop captive breeding, seed production, culture protocols, conservation strategies and isolation bioactive compounds of this high-valued species incommensurate with national and international perspectives.  相似文献   

3.
The intensive development of industry and urban structures along the seashores of the world, as well as the immense increase in marine transportation and other activities, has resulted in the deposition of thousands of new chemicals and organic compounds, endangering the existence of organisms and ecosystems. The conventional single biomarker methods used in ecological assessment studies cannot provide an adequate base for environmental health assessment, management and sustainability planning. The present study uses a set of novel biochemical, physiological, cytogenetic and morphological methods to characterize the state of health of selected molluscs and fish along the shores of the German North Sea, as well as the Israeli Mediterranean and Red Sea. The methods include measurement of activity of multixenobiotic resistance-mediated transporter (MXRtr) and the system of active transport of organic anions (SATOA) as indicators of antixenobiotic defence; glutathione S-transferase (GST) activity as an indicator of biotransformation of xenobiotics; DNA unwinding as a marker of genotoxicity; micronucleus test for clastogenicity; levels of phagocytosis for immunotoxicity; cholinesterase (ChE) activity and level of catecholamines as indicators of neurotoxicity; permeability of external epithelia to anionic hydrophilic probe, intralysosomal accumulation of cationic amphiphilic probe and activity of non-specific esterases as indicators of cell/tissue viability. Complete histopathological examination was used for diagnostics of environmental pathology. The obtained data show that the activity of the defensive pumps, MXRtr and SATOA in the studied organisms was significantly higher in the surface epithelia of molluscs from a polluted site than that of the same species from control, unpolluted stations, providing clear evidence of response to stress. Enhanced frequency of DNA lesions (alkaline and acidic DNA unwinding) and micronucleus-containing cells was significantly higher in samples from polluted sites in comparison to those from the clean sites that exhibited genotoxic and clastogenic activity of the pollutants. In all the studied molluscs a negative correlation was found between the MXRtr levels of activity and the frequency of micronucleus-containing hemocytes. The expression of this was in accordance with the level of pollution. The complete histopathological examination demonstrates significantly higher frequencies of pathological alterations in organs of animals from polluted sites. A strong negative correlation was found between the frequency of these alterations and MXRtr activity in the same specimens. In addition to these parameters, a decrease in the viability was noted in molluscs from the polluted sites, but ChE activities remained similar at most sites. The methods applied in our study unmasked numerous early cryptic responses and negative alterations of health in populations of marine biota sampled from the polluted sites. This demonstrates that genotoxic, clastogenic and pathogenic xenobiotics are present and act in the studied sites and this knowledge can provide a reliable base for consideration for sustainable development. Received: 2 March 1999 / Received in revised form: 2 August 1999 / Accepted: 3 August 1999  相似文献   

4.
A. A. Aleem 《Hydrobiologia》1990,208(1-2):7-15
Transgression on marine habitats (seagrass beds, coral reefs and mangrove stands) along the Jeddah coast and adjacent lagoons, owing to increased human activity, resulted in regression, degeneration or substitution of plant and animal communities.The effect of organic and thermal pollution on benthic life is examined. A need for baseline studies on such habitats is stressed for the identification and conservation of endangered biota.  相似文献   

5.
Mangrove sediments were collected from major mangrove stands on the Red Sea Coast of Saudi Arabia. Forty five isolates belonging to 12 genera were purified and five isolates as well as their consortium were found to be able to grow in association with petroleum oil as sole carbon source under in vitro conditions. The isolated strains were identified based on internal transcribed spacer (ITS) rDNA sequence analysis. The fungal strains with the greatest potentiality to degrade diesel oil, without developing antagonistic activity, were identified as Alternaria alternata, Aspergillus terreus, Cladosporium sphaerospermum, Eupenicillium hirayamae and Paecilomyces variotii. As compared to the controls, these fungi accumulated significantly higher biomass, produced extracellular enzymes and liberated larger volumes of CO2. These observations with GC–MS data confirm that these isolates displayed rapid diesel oil bioremoval and when used together as a consortium, there was no antagonistic activity.  相似文献   

6.
Blepharis saudensis, from small islands in the Red Sea of Jazan Provence, Saudi Arabia, is described as a new species and illustrated. This species differs from other known species in this genus by having a combination of long stems, oblong-lanceolate to linear leaves with entire margins and pubescence.  相似文献   

7.
Summary In a fringing reef at Aqaba at the northern end of the Gulf of Aqaba (29°26′N) growth rates, density, and the calcification rate ofPorites were investigated in order to establish calculations of gross carbonate production for the reefs in this area. Colony accretion ofPorites decreases with depth as a function of decreasing growth rates. The calcification rate ofPorites is highest in shallow water (0–5 m depth) with 0.9 g·cm−2·yr−1 and falls down to 0.5 g·cm−2·yr−1 below 30 m. Scleractinian coral gross production is calculated from potential productivity and coral coverage. It is mainly dependent on living coral cover and to a lesser extent on potential productivity. Total carbonate production on the reef ranged from 0 to 2.7 kg/m2 per year, with a reef-wide average of 1.6 kg/m2 perycar. Maximum gross carbonate production by corals at Aqaba occurs at the reef crest and in the middle fore-reef from 10 to 15 m water depth. Production is low in sandy reef parts. Below 30 m depth values still reach ca. 50% of shallow water values. Mean potential production of colonies and gross carbonate production of the whole reef community at Aqaba is lower than in tropical reefs. However, carbonate production is higher than in reef areas at the same latitude in the Pacific, indicating a northward shift of reef production in the Red Sea.  相似文献   

8.
Eighteen scleractinian coral species belonging to 13 genera, 8 families and 4 suborders have been identified from the lower and upper parts of the Upper Jurassic (Oxfordian) Hanifa Formation at Jabal Al-Abakkayn, central Saudi Arabia. Actinastrea bernensis, A. crassoramosa, Coenastraea hyatti, Stylina kachensis, Cryptocoenia slovenica, C. wegeneri, Isastrea hemisphaerica, I. bernensis, Montlivaltia cornutiformis, M. frustriformis, Collignonastraea jumarensis, Ovalastrea michelini and Vallimeandropsis davidsoni are believed to be recorded for the first time from the Jurassic rocks of central Arabia. Most corals have massive hemispherical and globular forms, and few corals have dendroid and conical growth forms. They occur as small, isolated patches, about 0.5 m thick and about 10–30 m wide, in argillaceous reefal limestones. The identified corals show Africa, north America, northern, southern and western Europe, and southern or eastern Asia corals. The low diversity and abundance as well as the small size of colonies are attributed to inimical palaeoecological factors throughout the reefoids formation such as muddy substratum, water turbidity, high rate of sedimentation.  相似文献   

9.
This study was conducted to investigate phytophagous and predatory mites associated with vegetable plants in Riyadh, Saudi Arabia. Eight phytophagous and 10 predacious mites were collected from 14 species of vegetable crops covering five major production localities. Out of these 18 mite species, 13 species are new to the mite fauna of Saudi Arabia. In addition, the two species, Tenuipalpus punicae and Agistemus exsertus, are reported for the first time on vegetable crops in Saudi Arabia. For each mite species found, notes on host plant association and occurrence period are given. An illustrated key for the identification of the 18 mite species reported in this study is provided and this can be used to improve the IPM programs by applying the local natural predatory mites in controlling mite pests in Saudi Arabia.  相似文献   

10.
The ctenodactylids from the Lower and Middle Miocene of Saudi Arabia are represented by two species: Sayimys intermedius (Sen and Thomas, 1979) and Sayimys assarrarensis sp. nov. This new taxon differs from the other species of Sayimys by its larger size together with an association of characters such as the presence of a metalophulid II in d4 and the strength of the anteroloph and posteroloph in P4. A cladistic analysis involving Prosayimys flynni , Sayimys obliquidens , S. assarrarensis sp. nov., S. intermedius, S. sivalensis, S. baskini , and Metasayimys curvidens is provided. Sayimys assarrarensis sp. nov. nests between Sayimys obliquidens and Metasayimys curvidens as a relatively primitive taxon.  相似文献   

11.
Marine algae are known to produce a wide variety of bioactive secondary metabolites and several compounds have been derived from them for prospective development of novel drugs by the pharmaceutical industries. However algae of the Red sea have not been adequately explored for their potential as a source of bioactive substances. In this context Ulva reticulata, Caulerpa occidentalis, Cladophora socialis, Dictyota ciliolata, and Gracilaria dendroides isolated from Red sea coastal waters of Jeddah, Saudi Arabia, were evaluated for their potential for bioactivity. Extracts of the algae selected for the study were prepared using ethanol, chloroform, petroleum ether and water, and assayed for antibacterial activity against Escherichia coli ATCC 25322, Pseudomonas aeruginosa ATCC 27853, Stapylococcus aureus ATCC 29213, and Enterococcus faecalis ATCC 29212. It was found that chloroform was most effective followed by ethanol, petroleum ether and water for the preparation of algal extract with significant antibacterial activities, respectively. Results also indicated that the extracts of red alga G. dendroides were more efficient against the tested bacterial strains followed by green alga U. reticulata, and brown algae D. ciliolata. Chemical analyses showed that G. dendroides recorded the highest percentages of the total fats and total proteins, followed by U. reticulata, and D. ciliolate. Among the bioflavonoids determined Rutin, Quercetin and Kaempherol were present in high percentages in G. dendroides, U. reticulata, and D. ciliolate. Estimation of saturated and unsaturated fatty acids revealed that palmitic acid was present in highest percentage in all the algal species analyzed. Amino acid analyses indicated the presence of free amino acids in moderate contents in all the species of algae. The results indicated scope for utilizing these algae as a source of antibacterial substances.  相似文献   

12.
Parrotfishes (family Scaridae) are important agents in marine bioerosion. Here, the feeding ecology of seven species of parrotfishes was studied on Egyptian Red Sea reefs. The most abundant species on both the reef flat and slope was Chlorurus sordidus. In contrast, C. gibbus had the lowest abundance on the reef flat, and Cetoscarus bicolor was the least abundant species on the reef slope. Scarus niger exhibited the highest feeding rate (98.9 bites 5 min− 1), followed by C. sordidus (76.5 bites 5 min− 1), whereas the rates for C. bicolor and C. gibbus were low (29.4 and 31.9 bites 5 min− 1, respectively). The daily feeding patterns of all seven species showed agreement in that activity was relatively constant over the day, with highest values in the early afternoon (1400 h) and a steady decrease until 1800 h. C. sordidus was more similar to S. niger and S. ghobban in showing somewhat higher activities in the morning (0800 h) followed by a slight decrease until noon. The average bite volumes of C. gibbus and C. bicolor were high (0.114 and 0.110 cm3, respectively), whereas S. niger had the lowest average value (0.002 cm3). Based on their feeding intensity, C. gibbus, S. ghobban and C. bicolor have high bioerosion rates on the Egyptian Red Sea reefs. Overall, S. ghobban is the most important bioeroder because it is more abundant than the other two species. All parrotfish species fed on dead coral and hard substrates which are rich in algae, but C. gibbus, C. bicolor and S. ghobban also fed on live coral on both reef zones; C. sordidus avoided live coral. The fresh scars on live coral were bigger than on dead coral because the three large parrotfish (C. gibbus, C. bicolor and S. ghobban) fed mainly on live corals.  相似文献   

13.
Summary This is the first study based on numerical analysis of the abundance of 11 scleractinian corals of depths at between 100–210 m in the Red Sea twilight zone. Two distinct coral communities were found: a Leptoseris fragilis community at a depth of 100–130 m (zone 1) and a Dendrophillia horsti community below 130 m (zone 2, 3). Population densities and coral coverage are very low; distribution of individuals is highly clumped. Highest observed densities on 100 m2 were 2720 individuals for L. fraglis, 2720 for D. horsti and 2260 for Javania insignis. Calculated coverage rates were maximally 3.6% (L. fragilis), 0.08% (D. horsti) and 0.11% (J. insignis). L. fragilis, the only symbiont bearing coral, was very abundant. It has an unusual depth range for a photosynthesising coral. Coral density is only weakly correlated with hard bottom coverage. Species diversity with an average of 8 species is highest at 120–170 m and decreases in shallower and deeper water. The study depth range is a transient zone for coral distribution. It contains the upper distribution limits of a few deep sea corals and the lower ones of several shallower water species. Ahermatypic corals, collected at 160–170 m depth, were transplanted from their original depth to 159, 118, 70 and 40 m; after one year most species survived transplantation far beyond their upper distributional limits. The symbiotic L. fragilis, collected at 120 m, survived transplantation to deep water (159 m) as well as shallow zones (90, 70 and 40 m). The study demonstrates the feasibility of line-transect methods for coral community studies with a submersible.  相似文献   

14.
Schindleria parva, a new species of the family Schindleriidae, is described from two specimens collected from the central Red Sea of Saudi Arabia. The new species is characterized by lack of pigmentation on the body, possession of an inconspicuous gas bladder and the presence of small teeth on the premaxillae. The holotype is a female of 11 mm standard length (SL) (11.9 mm total length) and the paratype is a male of 9 mm SL. Dorsal fin rays 10 (9) anal fin rays 9 (7). The body depth at pectoral-fin origin 5% (4%) of SL, depth at anal-fin origin 8% (7%) SL, predorsal length 63% (65%) SL, preanal length 72% (72%) SL, the first anal-fin ray situated below the fourth dorsal-fin ray), a total of 23 + 16 myomeres. The female contained a series of 30 rectangular eggs in a single row, whereas the male is characterized by a short rod-like urogenital papilla. Species of the genus Schindleria are likely the smallest marine vertebrates on the planet and S. parva is likely the smallest Schindleria species in the Red Sea. The global diversity of Schindleria is likely underestimated due to the paedomorphic features of this genus. Its fast generation times make it a species-rich genus of high turnover rates, thus potentially highly important for the trophic food webs of coral reefs. Thus, this finding advances knowledge on the biodiversity of the Red Sea, highlights its conservation significance, and contributes towards the understanding of the complexity of the coral-reef fish community.  相似文献   

15.
Population genetic studies in Saudi Arabia are performed for EsD, GPT, AcP, ADA, AK, 6-PGD, PGM, C3, Tf, Hp, Gc, Pi, Bf, Hb, ABO-blood groups and Rh-factor, level of the third component of complement and immunoglobulins. The data are compared with reported frequencies in European and African populations.  相似文献   

16.
Airborne Pollen grains and Spores of three different cities viz., Al-Khobar (1987–1988), Abha (1991–1992) and Hofuf (1992–1993) in Saudi Arabia were studied using Burkard Volumetric Seven-Day Spore Trap. The data were analyzed in relation to their allergenic capability and one-year pollen and spore calendars were designed to correlate the patients’ symptoms as well as for selection of appropriate allergen extracts for diagnosis and treatment of allergic diseases. Amongst pollen group, Amaranthus viridis, Plantago spp., Chenopodium album, Ricinus communis, Rumex vesicarius, Juniperus spp., Parkinsonia aculeata, Prosopis spp., and Phoenix dactylifera were some of the frequent types. Amongst the fungal spores group Cladosporium, Smuts spores, Colored basidiospores, Alternaria, Ulocladium and Drechslera were the dominant types.  相似文献   

17.
Middle East respiratory syndrome is the acute respiratory syndrome caused by betacoronavirus MERS-CoV. The first case of this disease was reported from Saudi Arabia in 2012. This virus is lethal and is a close relative of a severe acute respiratory syndrome (SARS), which is responsible for more than 3000 deaths in 2002–2003. According to Ministry of Health, Saudi Arabia. The number of new cases is 457 in 2015. Riyadh has the highest number of reports in comparison to the other cities. According to this report, males are more susceptible than female, especially after the age of 40. Because of the awareness and early diagnosis the incidence is falling gradually. The pre-existence of another disease like cancer or diabetic etc. boosts the infection. MERS is a zoonotic disease and human to human transmission is low. The MERS-CoV is a RNA virus with protein envelope. On the outer surface, virus has spike like glycoprotein which is responsible for the attachment and entrance inside host cells. There is no specific treatment for the MERS-CoV till now, but drugs are in pipeline which bind with the spike glycoprotein and inhibit its entrance host cells. MERS-CoV and SAR-CoV are from the same genus, so it was thought that the drugs which inhibit the growth of SARS-CoV can also inhibit the growth of MERS-CoV but those drugs are not completely inhibiting virus activity. Until we don’t have proper structure and the treatment of MERS-CoV, We should take precautions, especially the health care workers, Camel owners and Pilgrims during Hajj and Umrah, because they are at a higher risk of getting infected.  相似文献   

18.
The aim of this study was to identify the main weed communities in Al-Jouf province in northern Saudi Arabia. Moreover, the composition and diversity of these communities were studied in relation to soil variables and crop type. Some 54 stands representing olive orchards, date palm orchards, wheat crop and watermelon crop were studied, using ten quadrats (1 × 1 m) per stand. A total of 71 species belonging to 22 families and 61 genera were observed. The classification of vegetation using the Two Way Indicator Species Analysis (TWINSPAN) resulted in the recognition of four vegetation groups representing wheat crop, orchards in winter season, orchards in summer season and watermelon crop. These results suggested the importance of both crop and season for the formation of weed community. Detrended Correspondence Analysis (DCA) showed that these groups are clearly distinguished by the first two DCA axes. The species richness was higher in both olive and date palm orchards than in wheat and watermelon crops. This pattern of species richness could be related to farm management practices and habitat micro-heterogeneity. Soil electrical conductivity, organic carbon and soil texture showed significant correlations with species richness and the cover values of some dominant species, suggesting the significant role of soil characteristics in weed community structure and diversity.  相似文献   

19.
Three common Red Sea soft corals (Cnidaria: Anthozoa), Nephthea sp, Dendronephthya sp and Heteroxenia fuscescens sting humans. Nematocyst venoms of each animal are lethal to mice and hemolytic to human erythrocytes. However, these hemolysins are partially inhibited by known anti-hemolytic agents. Venoms and their gel chromatography-separated fractions have different dermonecrosis and vasopermeability potency in mouse skin. The venom of Heteroxenia fuscescens (Hf) was more lethal (LD50: 0.7 mg/kg), with one prominent 97-kDa protein fraction (LD50: 0.55 mg/kg). Hf venom was more hemolytic, more dermonecrotic, and had more vasopermeable factors than that of the two other species. SDS polyacrylamide gel electrophoresis of soft coral whole venoms and fractions showed different protein molecular masses ranging from 200 to less than 6 kDa. High IgG titers were assayed from venom-sensitized mice blood sera. Enzyme-linked immunosorbent assays (ELISA) marked significant immunological cross-reaction between the studied soft coral venoms and their bioactive fractions.  相似文献   

20.
The aim of the study was to detect the infection level of honey bees with Nosema apis and/or Nosema ceranae using microscopic and molecular analysis from indigenous honeybee race of eight Saudi Arabian geographical regions. A detailed survey was conducted and fifty apiaries were chosen at random from these locations. Infection level was determined both by microscope and Multiplex-PCR and data were analyzed using bioinformatics tools and phylogenetic analysis. Result showed that N. ceranae was the only species infecting indigenous honeybee colonies in Saudi Arabia. As determined by microscope, Nosema spores were found to be in 20.59% of total samples colonies, while 58% of the samples evaluated by PCR were found to be positive for N. ceranae, with the highest prevalence in Al-Bahah, a tropical wet and dry climatic region, whereas low prevalence was found in the regions with hot arid climate. Honeybees from all eight locations surveyed were positive for N. ceranae. This is the first report about the N. ceranae detection, contamination level and distribution pattern in Saudi Arabia.  相似文献   

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