علوم زیستی دریا
Mahdie Amirinezhad; Narges Amrollahi Biuki; Morteza Yousefzadi; Arash Ghaderi
Abstract
This study investigated the green synthesis of cerium oxide nanoparticles using natural marine extracts. Characteristic peaks for CeO2 with X-ray diffraction spectrum to crystal planes (111), (200), (220) (311), (331), (420), and (422) are related. In the SEM images, the synthesized cerium oxide ...
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This study investigated the green synthesis of cerium oxide nanoparticles using natural marine extracts. Characteristic peaks for CeO2 with X-ray diffraction spectrum to crystal planes (111), (200), (220) (311), (331), (420), and (422) are related. In the SEM images, the synthesized cerium oxide nanoparticles are generally spherical with a size of about 10 to 12 nm. the FTIR analysis indicated the presence of prominent peaks that showed the presence of this nanoparticle in different capacity states of Ce +3, Ce4+ acts as an antioxidant on the surface of nano cerium. Nanoparticles synthesized from algae at concentrations of 1000, 500, and 250 µg /ml showed between 60-65% DPPH free radical inhibition. The highest reduction rate of macroalgae Sargassum ilicifolium at a concentration of 500 µg /ml, it is a significant difference between nanoparticles synthesized from the available extracts and tested at different concentrations. Antibacterial activity was observed (P≤0.05). It showed that Gram-negative bacteria are more resistant to CeO2 nanoparticles than Gram-positive bacteria. INTRODUCTIONToday, biological methods of nanoparticle synthesis using microorganisms, natural extracts, and nutrients have been suggested as suitable alternatives to chemical and physical methods (Das et al., 2013). Researchers have reported that cerium nanoparticles are effective in dealing with oxidative stress and have an antioxidant role, so these nanoparticles can act as a remover of various forms of reactive oxygen in many physiological and biochemical reactions in the body of living organisms (Dhall et al. al., 2017(. Microalgae are the main group of photoautotrophic organisms known as potential sources of secondary metabolites, phenolic compounds, pigments and polysaccharides. Biosynthesis targets algal secondary metabolites as reducing agents for stabilization of nanoparticles (NPs) (Barciela et al., 2022). Metabolites extracted from starfish with low molecular weight have remarkable characteristics. These isolated compounds include steroids, anthroquinones, alkaloids, phospholipids and peptides, which are a rich source of activity against microbes and have many uses in the field of medicine (Baharara et al., 2020). In this study, the antioxidant and antibacterial properties of green cerium oxide nanoparticles synthesized from marine extracts have been investigated. MATERIALS AND METHODS Sargassum ilicifolium macroalgae was collected from the coast of Chabahar and transported to the laboratory. Then the samples were washed several times with distilled water in order to separate the mud and dried in the shade and at a suitable temperature for a week and then ground to powder. Brittle star Ophiocoma scolopendrina was collected from Qeshm Island at the time of low tide and dried with a freeze dryer at -40C and then powdered with an industrial mill. In order to extract and synthesize CeO2NPs nano cerium oxide, 10 grams of powdered each of the samples was added to 100 ml of double distilled water and stirred for 3 to 4 hours at 60 degrees Celsius, then it was collected with filter paper and then Whitman. In an Erlenmeyer flask, 100 ml of 0.05 M of Ce(NO3)3.6H2O and 20 ml of distilled water were added to it and this solution was stirred using a magnetic stirrer until a homogeneous solution was formed (Altaf et al. al., 2021). Then 40 ml of the extract was added to the solution and the final volume was brought to 100 ml with distilled water and the reaction mixture was stirred on a hot magnetic plate with a temperature of 70-80 degrees Celsius for 3-4 hours. The formed particles after sufficient stirring time were centrifuged at 5000 rpm for 10 minutes, the nanoparticles were repeatedly washed with deionized water and dried in an oven at 60 degrees for 6 hours. Then, the obtained product was calcined in the oven at 400°C for 2 hours to produce a yellow powder of cerium oxide (Elahi et al., 2019). In the test of measuring the antioxidant capacity by the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical method, concentrations of 1000, 500, 125, 250, 62.5 and 31.25 μg/ml were made from 10 mg/ml stock, from 100 μl of each concentration was taken and poured into 96-well plates in triplicate. Also, 100 microliters of 0.3 mM DPPH solution (394.3 g/mol) was added. The 96-well plates were placed in the dark for 30 minutes, and the absorbance of the samples was read by an Elizarider device at a wavelength of 517 nm. RESULTS In the FT-IR study, the peaks around 1417, 1575, and 1577, 1432 cm2 in samples A and B are related to carbonate compounds. Scanning electron microscopy (SEM) has shown that the nanoparticles are spherical and tend to aggregate.The highest reduction rate against ascorbic acid was observed in Sargassum macroalgae at a concentration of 500 μg/ml. DISCUSSION AND CONCLUSION The highest inhibitory activity of NPS synthesized for S. ilicifolium was observed (65.45 ± 0.5% at 1000 μg/ml). The basis of the biological activities of cerium nanoparticles is the Ce3+/Ce4+ surface ratio, the cycle of oxidation and reduction between the Ce3+ and Ce4+ states, which have a unique ability to absorb and release oxygen on their surface and play a key role in antioxidant activity (Dhall and Self, 2018).
علوم زیستی دریا
Sanaz Ahmadi Falehi; Ahmad Savari; Nasrin Sakhaei; Faedeh Amini; Babak Doustshenas
Abstract
Planktonic crustaceans are of specific importance in energy transfer due to their location in the middle links of the food chain of aquatic ecosystems. Therefore, they directly affect the abundance and diversity of the higher categories of the food pyramid, especially stocks and fishery resources. In ...
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Planktonic crustaceans are of specific importance in energy transfer due to their location in the middle links of the food chain of aquatic ecosystems. Therefore, they directly affect the abundance and diversity of the higher categories of the food pyramid, especially stocks and fishery resources. In this study, the impact of a tidal cycle on the zooplanktonic Crustacean ecosystem in the estuarine Bahmanshir River (Northwestern Persian Gulf) was studied. Our samples were collected during the spring of 2018 by plankton net with mesh sizes of 100 μm. Samples were taken at 5 stations to have a tidal effect on the abundance of zooplankton, approximately from 8:00 to 18:00 every two hours. In general, 72 species belonging to 28 families related to 3 groups of crustaceans named Cirripedia, Cladocera, and Copeoda were observed. The highest percentage of relative abundance was related to Cladocera with 35%, which was caused by the abundance of Daphnia mendotae. The highest diversity (Shannon index = 2.71 ± 0.04) of copepods was revealed to be caused by the large number of species at station 5 (near the mouth of the Bahmanshir River). Most species among the families belong to the Acartiidae family, which has 10 species of Acartia. The results of PCA analysis showed that among environmental factors, salinity has a direct effect on the total density, density of Harpacticoida and Calanoida, in the first component. The tides appear to significantly affect the density and types of planktonic crustaceans during the mentioned springtime periods. Our results showed relatively strong influence of the tidal cycle on the spatial pattern of Copepod assemblages in the study area. This study may be useful for future biological monitoring and seawater salinity intrusion into rivers in the northwest of the Persian Gulf.
علوم زیستی دریا
Adel Ghabtani; Seyed Mohammad Mousavi; Annahita Rezaie; Mohammad Zakeri; Isac Zamani
Abstract
The purpose of this study was to evaluate the effects of three commercial probiotics (Bio-Aqua®, Bio-Aqua pond®, and Multi Behsil 100) on the growth, nutrition, and biochemical parameters of common carp fingerlings. For this purpose, 210 common carp fingerlings (with a mean weight: 9.6±0.02 ...
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The purpose of this study was to evaluate the effects of three commercial probiotics (Bio-Aqua®, Bio-Aqua pond®, and Multi Behsil 100) on the growth, nutrition, and biochemical parameters of common carp fingerlings. For this purpose, 210 common carp fingerlings (with a mean weight: 9.6±0.02 g and mean length: 12.9±0.32 cm) were randomly divided into 7 treatments (treatment 1 (control): basic diet without probiotics, treatment 2: 0.2 g of Bio-Aqua®, treatment 3: 0.1 g of Bio-Aqua®, treatment 4: 0.002 g/L of Bio-Aqua pond® dissolved in tank water, treatment 5: 0.001 g/L Bio-Aqua pond ® dissolved in tank water, treatment 6: 0.2 g of Multi Behsil 100, and treatment 7: 0.1 g of probiotic Multi Behsil 100) in triplicates, and 10 fish in each replicate. The commercial probiotics were added to the commercial diet, and the fish were fed based on body weight percentage for 60 days. Based on the results, the use of probiotics Bio-Aqua® and MultiBehsil 100, caused positive effects on the growth and nutrition parameters of common carp, although the use of 0.1 g of Bio-Aqua® per kilogram of the diet of common carp led to an improvement in growth, although, increasing the amount of this probiotic at the level of 0.2 g/kg led to negative effects on growth performance. The use of Multibehsil 100, caused positive effects on common carp. Thus, the best effect on growth performance and body composition was seen in the diet containing MultiBehsil 100 (0.1 and 0.2 g/kg of basic diet). Therefore, it can be concluded that the use of MultiBehsil 100 and Bio-Aqua® have favorable effects on common carp.
علوم انسانی دریا
Mohammad Amin Kouhbor; Homayoun Yousefi; Mohammad Esmaeil Doust; Arash Amraei
Abstract
The purpose of this present study was to identify the factors affecting the development of the maritime tourism industry in line with the economic growth of the ports of Khorramshahr and Abadan and its effect on attracting tourists in the Arvand Free Zone. On the other hand, citing the research ...
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The purpose of this present study was to identify the factors affecting the development of the maritime tourism industry in line with the economic growth of the ports of Khorramshahr and Abadan and its effect on attracting tourists in the Arvand Free Zone. On the other hand, citing the research objective, ranking the factors affecting the development of the maritime tourism industry will increase the income of the ports and maritime organizations of Abadan and Khorramshahr, Arvand Free Zone, as well as creating job opportunities in Khuzestan Province. The method of this research is applied in terms of its purpose and in terms of descriptive-survey nature which is conducted by interviewing, observing, studying, and ... with a deductive approach to identify influential factors. On the other hand, in the quantitative part of the research, the analysis has been carried out. Data were analyzed by using SPSS and LISREL software based on the T-test and structural equations model. Based on the results, natural variables of other variables were more effective than those with a T-statistic of 14.84 and an impact factor, of 0.85, which is a significant amount. This value is considered strong in terms of the severity of the effect since it is more than 70%. On the other hand, the variable of political factors, with the value of t statistic, is 9.71, the coefficient of influence is 0.59, and the effect of average intensity has the least effect on attracting tourists to the Arvand Free Zone.
The method of this research is applied in terms of its purpose and in terms of descriptive-survey nature which is conducted by interviewing, observing, studying and ... with a deductive approach to identify influential factors. On the other hand, in the quantitative part of the research, the analysis has been carried out. Data were analyzed by using SPSS and LISREL software based on the T-test and structural equations model. Based on the results, natural variables of other variables were more effective than those with T-statistic 14.84 and impact factor, 0.85, has a significant amount. This value is considered strong in terms of the severity of the effect since it is more than 70%. On the other hand, the variable of political factors, with the value of t statistic, is 9.71, and the coefficient of influence is 0.59, and the effect of average intensity has the least effect on attracting tourists in Arvand Free Zone.
علوم زیستی دریا
Afshin Sotoudehpour; Aghil Madadi; Sayyad Asghari
Abstract
Abstract
Remote sensing data has played an important role in natural resource management studies in recent years. These data, especially in water resources studies and research, have many uses. Among water-related studies, the use of water indexes in recent years has been widely considered. ...
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Abstract
Remote sensing data has played an important role in natural resource management studies in recent years. These data, especially in water resources studies and research, have many uses. Among water-related studies, the use of water indexes in recent years has been widely considered. These indexes have grown and developed with the advancement and production of satellite images and their precision increased dramatically. In this research, Landsat 8 and Sentinel A2 satellite images were used on the coast of Bushehr on the Persian Gulf. 8 water indexes were selected and executed on images. Despite the fact to exist two classes of water and land unsupervised classification were applied to images Finally, the overall accuracy and kappa coefficient values range from 77.0% to 99.6% and 0.55 to 0.99 respectively. For Landsat images, the Modified Normalized Difference Water Index (MNDWI) and the Normalized Difference Pond Index (NDPI) were the best indexes. Water Ratio Index (WRI) and Normalized Difference Turbidity Index (NDTI) were recognized as the worst index. For Sentinel 2A images, the Modified Normalized Difference Water Index (MNDWI) and the Normalized Water Difference Index (NDWI), respectively, were the best. and the Automatic Water Extraction Index (AWEI_NSH) had the worst result. In general, the performance of the water indexes, and the accuracy level of the sentinel 2A images was significantly higher than the Landsat 8 images This factor can be due to the higher spatial resolution of Sentinel images. For both Landsat 8 and Sentinel A2 images the Modified Normalized Difference Water Index (MNDWI) has the best results.
Keywords: Sentinel 2A, landsat8, NDWI Index, MNDWI Index, NDPI Index
INTRODUCTION
More than 70% of the earth's surface is covered by water, then the use of remote sensing data to extract information from oceans, seas, and closed waters is very important (Alavipanah, 2004). Remote sensing data with different spatial, spectral, and temporal resolutions have provided a valuable resource for evaluating the water level and its changes in recent decades (Jawak et al., 2015). Extracting water from satellite images is more than two decades old. The use of satellite images for a general overview of phenomena and terrestrial resources recording the characteristics of phenomena by sensors and finally analyzing them in this field can help us a lot (Zarghami, 2011). activities such as checking water quality including salinity studies, checking suspended substances and sediments, checking watercolor, and chlorophyll level, and also quantitative studies of water sources are among the actions that can be done using remote sensing (Hashemi et al., 2018). Using such a technique to better control and manage the environment in advanced countries is considered a strategic technology (Mobasheri, 2014).
MATERIALS AND METHODS
The studied area is a 130-kilometer stretch from Bushehr Beach in Bushehr province. The area of the study area is about 182,650 hectares, which is located at 50° 45ʹ to 51° 6ʹ E, 28° 42ʹ to 29° 10ʹ N. The Landsat 8 satellite image of March 15, 2018, and July 17, 2001, as well as the SentinelA2 image of March 26, 2018, were used. Both images were taken with a short time interval. Landsat 8 images had a spatial resolution of 30 meters. In the Sentinel images, bands with a resolution of 10 meters were used, and for the use of other bands, the bands were unified using the Fusion operation. In this research, the 1:50000 topographic map of the Geographical Organization of the Armed Forces was also used. Also, soil maps from the Jihad Agriculture and Geology Organization with a scale of 1: 100,000 were obtained from the Mapping Organization and used. 8 indices were used: Normalized Difference Water Index (NDWI), Modified Normalized Difference Water Index (MNDWI), Normalized Difference pond index (NDPI), Normalized Difference Turbidity index (NDTI), Water Ratio Index (WRI), Normalized Difference Water Index (NDWI_A)), AWEI, AWEI_SH. To determine the correctness of the classified map, the control points prepared from the Google Heritage images were used along with 35 points taken using GPS. The Kappa coefficient was evaluated
RESULTS
By applying blue indices on both Landsat 8 and Sentinel A2 images, the blue areas were separated from the dry environment. In Landsat 8 images, the MNDWI index with an overall accuracy of 98% and a kappa coefficient of 0.97 had the best results, and the WRI index with an overall accuracy of 78% and a kappa coefficient of 0.55 presented the worst results. In Sentinel A2 images, the MNDWI index with an overall accuracy of 99% and a kappa coefficient of 0.99 had the best result, and the AWEI_NSH index with an accuracy of 77% and a kappa coefficient of 0.55 presented the worst result. For Landsat images, among the implemented indices, the modified normalized water difference index (MNDWI) and the normalized lake, wetland index (NDPI) were the best indices. Water ratio indices (WRI) and normalized turbidity difference index (NDTI) were recognized as the worst indices. For Sentinel A2 images, the modified normalized water difference index (MNDWI) and normalized water difference index (NDWI) had the best results, and the automatic water extraction index (AWEI_NSH) had the worst results. In general, in the implementation of blue indices, the level of accuracy and precision in the Cetinel A2 images was significantly higher than that of the Landsat 8 images.
CONCLUSION
In the present study, in general, the accuracy and precision of Sentinel A2 images were better than Landsat 8 in most of the indicators, and the higher spatial resolution of Sentinel images can be a reason for presenting better results. For both images, the modified normalized water difference index (MNDWI) was recognized as the best index that could distinguish water phenomena from other phenomena well; Although in the mentioned index, different results can be presented due to the combination of different bands. In both Landsat 8 and Sentinel A2 images, the automatic water extraction index (AWEI_NSH) presented the worst result in this index due to the high reflection of phenomena such as rocks, sand, the presence of shadows, and clouds with negative effects on the mentioned index. It is confused with water phenomena. On the other hand, this index showed that they provide poor results for revealing shallow waters (such as estuaries). In general, it can be said that the overall accuracy obtained in most of the applied indices shows reliable values, which is proof of the optimal choice of thresholds in these indices. Finally, the monitoring of the beaches of Bushehr from 2001 to 2018 shows that the beaches of Bushehr have undergone many changes during this period, and these changes were in the form of a regression of the coastline. The imbalance between the processes of erosion and sedimentation on this coast has caused the channel and estuary of most estuaries to shift and change in width.
References
Alavipanah, S.K., 2004. Application of remote sensing in the earth sciences (soil). University of Tehran Press. Tehran, Iran. (In Persian)
Hashemi, S.N., Akbarinasab, M. and Safarrad, T., 2018. The Detection of the Plume of the Arvand River Using Satellite Images. Hydrogeomorphology, 4(13), pp.147-164.
Jawak, S.D., Kulkarni, K. and Luis, A.J., 2015. A review on extraction of lakes from remotely sensed optical satellite data with a special focus on cryospheric lakes. Advances in Remote Sensing, 4(3), pp.196-213. DOI: 10.4236/ars.2015.43016
Mobasheri, M., 2014. Principles of physics in remote sensing and satellate technology. Khaje nasir university of technology publishers. Tehran, Iran. (In Persian).
Zarghami, M., 2011. Effective watershed management; case study of Urmia Lake, Iran. Lake and Reservoir Management, 27(1), pp.87-94. https://doi.org/10.1080/07438141.2010.541327.