علوم زیستی دریا
Zahra Yarahmadi; Bita Archangi; Ahmad Savari; Mohammad Bagher Nabavi
Abstract
The objective of this study was to morphological description and phylogenetic study of Ornithocercus magnificus in Bandar Abbas waters. The genus Ornithocercus is a heterotrophic dinoflagellate of the family Dinophysaceae. The samples were collected using a phytoplankton net (mesh size: 20 µm) ...
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The objective of this study was to morphological description and phylogenetic study of Ornithocercus magnificus in Bandar Abbas waters. The genus Ornithocercus is a heterotrophic dinoflagellate of the family Dinophysaceae. The samples were collected using a phytoplankton net (mesh size: 20 µm) equipped with a flowmeter in surface waters. The plankton samples were scanned and identified with an inverted microscope. Then, the SSU rDNA gene fragment from individual cells have been amplified using the polymerase chain reaction and sequenced for the Iranian strain of this species. Phylogenetic analyzes were performed by Maximum Likelihood (ML) and Maximum parsimony (MP) methods. In this study, two new sequences of SSU rDNA from O. magnificus were reported for the first time and deposited in the GenBank. Morphological studies showed that the isolated cells from Iranian water were O. magnificus. Generally, the results showed; the morphological results of O. magnificus were matched with the molecular results of this study. Phylogenetic analysis grouped isolated Iranian sequences with O. magnificus and formed a monophyletic clad with other members of this genus as sister groups. The genus Histioneis is the closest relative to Ornithocercus.
علوم غیرزیستی دریا
Yasaman Gandomi; Ahmad Savari; Babak Doustshenas; Saleh Arekhi
Abstract
The increasing application of remote sensing for mangrove mapping and monitoring is practical for sustainable management of the biological resources. The emergence of several vegetation indices (VIs) has certainly given significant impacts on mangrove and other forest mappings. In this study, four different ...
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The increasing application of remote sensing for mangrove mapping and monitoring is practical for sustainable management of the biological resources. The emergence of several vegetation indices (VIs) has certainly given significant impacts on mangrove and other forest mappings. In this study, four different vegetation indices including Normalized Different Vegetation Index (NDVI), Simple Ratio (SR), Soil Adjusted Vegetation Index (SAVI) and Triangular Vegetation Index (TVI) were compared to discover a suitable vegetation index for identifying mangrove area in Nayband bay, Boushehr, Iran and using landsat imagery with 30-m from 2012. Maximum Likelihood Classifier (MLC) was used to classify Mangrove and NonMangrove area. The results demonstrated that the best accuracy (96.85%) was from combination between 7 landsats spectral bands and some vegetation indices including NDVI and SAVI.
علوم زیستی دریا
Nasrin Sakhaei; Masomeh Sheyamizadeh; Babak Doustshenas; Ahmad Savari; Mohammad bagher Nabavi
Abstract
The purpose of this study was to identify and investigate the density and distribution of copepoda and cladosera and the structural analysis of their dominant species in the Arvand river by SEM (scaning electron microscope). Sampling was conducted with 50 μm mesh size plankton net at 6 stations and ...
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The purpose of this study was to identify and investigate the density and distribution of copepoda and cladosera and the structural analysis of their dominant species in the Arvand river by SEM (scaning electron microscope). Sampling was conducted with 50 μm mesh size plankton net at 6 stations and four times (in different seasons) with three reputation. The samples were detected by phase contrast microscopy and SEM. Totally 15 species of copepoda and 5 species of cladocera were identified in the river. The highest density of planktonic crustaceans including copepoda and cladocera with a mean density of 9481 and 3155 individuals per cubic meter was calculated in summer. These species, Acartia faoensis, Canthocalanus pauper, Subecalanus flemingeri, Labidocera acuta, which accounted for 61% of the total copepods abundance and 54% of the cladosera abundance were related to Moina macrocopa and Daphnia longisoina. The integrity of river were study using saprobic index which showed mesosaprobic-β (medium pollution) with mean 2.48 point.
علوم زیستی دریا
Halimeh Rajabi; Hossein Zolgharnen; Ahmad Savari; Alireza Amouzandeh; Nabi Jomehzadeh
Abstract
In this paper, the venom apparatus of the marine cone snail C. frigidus that is peptide toxins manufacture section with pharmacological effect have been studied.The venom apparatus of about 6 specimens were removed and divided to 3 parts: The venom bulb, the proximal portions of the venom apparatus (close ...
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In this paper, the venom apparatus of the marine cone snail C. frigidus that is peptide toxins manufacture section with pharmacological effect have been studied.The venom apparatus of about 6 specimens were removed and divided to 3 parts: The venom bulb, the proximal portions of the venom apparatus (close to venom bulb), the distal portions of the venom apparatus (close to pharynx). Then were fixed in Bouin's for 48 hours and transferred to 70% ethanol. After dehydration and Paraffin embedded, they were cut by microtome, collected on glass slides, stained with Haematoxylin-Eosin and studied by light microscope. The results showed that the venom bulb has longitudinal, transversal muscles, and a row of cubic cells with round nuclei. The proximal and the distal parts are composed of elongated cylindrical cells with the basal ganglia. The epithelial cells of the venom apparatus have abundant granules and in the distal part that are larger than the proximal. The passageway between the lumen of the venom duct and the pharynx is a channel that lead to the radula bag containing radula with different degrees of a formation. So, C. frigidus venom production and delivery was performed by synthesis in the venom apparatus, storage toxin in the radula teeth and the venom injection is done by the venom bulb and the best section for toxin peptide extraction is the distal portion of the venom apparatus. The reason is that this part, is active in the secretion of mature toxins that can use for Medicinal purposes.
علوم زیستی دریا
Emad Koochaknejad; Ahamd Savari; Alireza Safahieh; Gholamreza Eskandari
Abstract
In this study age, growth and maturity of Hilsa shad in Khuzestan province were analyzed. 394 number of fishes from marine habitat (Life-Boseif), estuaries (Bahmanshir and Arvand) and rivers (Bahmanshir and Karoon) from February 2014 to September 2014 were collected using commercial fishing with gill ...
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In this study age, growth and maturity of Hilsa shad in Khuzestan province were analyzed. 394 number of fishes from marine habitat (Life-Boseif), estuaries (Bahmanshir and Arvand) and rivers (Bahmanshir and Karoon) from February 2014 to September 2014 were collected using commercial fishing with gill net. Total length and wet weight of each fish were measured with precision of 1 cm and 1 gram. Sagittal otoliths were extracted for age determination of the fish. Then abdominal cavity of each sample were opened for determining sex and maturity stage. Growth parameters were calculated using von Bertalanffy growth function (L∞=58.365, K=0.26, t0=-0.16). Phi-prime constant was obtained 2.95. Length and age at first maturity were obtained 27.32cm and 2.4 g respectively using logistic model to fit a and b parameters with observed data in spawning season.
علوم زیستی دریا
shafa hoveizavi; Babak Doustshenas; Gholamreza Eskandari; Ahmad Savari; Hossein Mohammadasgari
Abstract
The main purpose of this study was to describe and estimate the seasonal pattern of discard fish in the waters of the Persian Gulf coasts in Khuzestan. sampling was carried out Monthly by using fishing boats in the waters of Khuzestan province for one year in fishing areas of Lifeh, Boseif, Khure-mussa ...
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The main purpose of this study was to describe and estimate the seasonal pattern of discard fish in the waters of the Persian Gulf coasts in Khuzestan. sampling was carried out Monthly by using fishing boats in the waters of Khuzestan province for one year in fishing areas of Lifeh, Boseif, Khure-mussa and Bahrakan.Discard fish samples were included 61 species from 37 families, nearly 39 percent commercial and 61 percent of non- commercial species. Rayfish and catfish have been observed in most fishing nets. Average size of most species particularly bony fish were under 15 cm. The amount of discard fish per unit of fishing effort is not significantly different between seasons. The highest portion of the catch belongs to Rayfishes. Total discard fishes of gillnets were estimated 3162 tones. Total weight of commercial fishes with small size in trash fish was estimated 225 tones. The rate and proportion of discard fish in total catch of gillnet was estimated 0.23 and 0.31 respectively. Chondrichthyes with 12 species and 60% of gillnet catch has the highest percentage of discard fish of gillnet. A large number of commercial species with small size such as Otolithes ruber (Schneider, 1801), ( Scomberomorus commerson (Lacepede, 1801) and Scomberoides commersonnianus(Lacepede, 1801) could be due to the role of nursery grounds in Khuzestan coastal waters.
علوم زیستی دریا
Haleh Ali Abedi; Seied Mohammad Bagher Nabavi; Babak Dustshenas; Ahmad Savari; Mohammad Sharif Ranjbar
Abstract
To investigate some bioecological parameters of dolphins between Qeshm and Hengam Islands waters, the present field study was started on November 2014 and finished on may 2015. During this study morphological features of individuals, within dolphin groups, distribution and reproduction of the Indo-Pacific ...
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To investigate some bioecological parameters of dolphins between Qeshm and Hengam Islands waters, the present field study was started on November 2014 and finished on may 2015. During this study morphological features of individuals, within dolphin groups, distribution and reproduction of the Indo-Pacific Bottlenose dolphin (Tursiops aduncus) and their activities at the sea surface were registered using camera systems. At the same time a field questioner form was design to collect the local fisherman informations regarding to dolphins behaviors in the region. During this study one dolphin species namely Tursiops aduncus (Indo-Pacific Bottlenose Dolphin) was identified. The breeding period of Indo-Pacific Bottlenose dolphin was in spring season and a newborns were observed in April 2015. According to field observations, the mean number of Indo-pacific Bottlenose dolphin groups was 23/13±5/49 with 2 newborns in April 2015.Key words: Indo-pacific bottlenose dolphins, Bioecological parameters, Persian Gulf, Qeshm Island, Hengam Island.