مجله علوم و فنون دریایی
سال هفدهم شماره 1 (بهار 1397)

In this study, two populations of Aphanius ginaonis (Holly, 1929) and Aphanius dispar (Ruppell, 1828) were examined to determine genetic diversity using PCR-RFLP technique. A total of 60 individual specimens were collected from Hormozgan and Bushehr internal waters, comprising two sampling sites; from Geno hot spring (30 individuals of A. ginaonis) and Mir Ahmad hot spring (30 individuals of A. dispar). The D-loop region of mitochondrial DNA (550 bp) was amplified using PCR followed by RFLP analysis based on 5 restriction endonucleas enzymes (AluI, DpnI, Eco47I, HindIII HinfI). In order to undertake data analysis, Arlequin 3.11 was applied. Results at population levels indicated that Geno individuals have more haplotype diversity than Mir Ahmad individuals (9 and 3 haplotypes respectively). However, further investigation using genetic techniques is required to clarify the molecular history and evolution of Aphanius species in this area. Results obtained from this research would be applicable to understand conservation genetics and management of this important fish species in Iran.

Dust prediction such as prediction of wind and rain needs to synoptic information to the earth's surface, upper layers of the atmosphere, the prediction maps of land surface and upper levels as well as using radar and satellites. The purpose of this study, use of remote sensing technology and MODIS images to estimate dust optical depth on the Persian Gulf surface and estimating the linear correlation relationship between the dust measurements in ground and atmospheric. The dust optical depth calculated using the code developed in MATLAB software. Evaluation of extracted data conducted using Pearson correlation coefficient, RMSE and RMSD index. In this study, optical depth obtained from image processing compared with the optical depths obtained from AERONET network. The evaluation results showed a high and significant correlation between the obtained optical depth and optical depths obtained from AERONET network (R2=0.99). The best and most suitable mode demonstrated for 1.243 and 1.643 bonds. At all stations, AOD value obtained from satellite image is bigger than AOD amount corresponding to the AERONET station and the algorithm used has overestimated. The cause of this more estimate can be use of limited particle's effective radius, because the scope of this effective radius is limited at the distribution of particle size in log-normal. Error resources at the retrieving particulate matter was defined such as sensor calibration error, pollution on the radiation angle, or poor predictor of water reflection.

Taxonomic studies on the Anomura larvae of the Persian Gulf are relatively few. This research has been done on larval stage of Diogenes sp. (Anomura: Diogenidae)on coastal waters of Bahmanshir River. Anomura is a group of decapodcrustaceans, including hermit crabsthat are cosmopolitan and could be found from coastal waters to 5000 m in depth. The larval stages differ among families of Anomura. Anomura larvalsamples collected by plankton net (mesh size of 300 µm) from seven stations in February 2011 to October 2012. Planktonic larval were sampled from the Bahmanshir River in north of the Persian Gulf. The larval stages illustrated and described in detail for Diogenes sp. Finally Diogenes sp. were identified and their schematic figures were made using Camera Lucida. Maximum value of the average abundance of larvae (12.3±3.4 ind.m3) was recorded in May. Also positive relationship betweensalinity with frequency of Diogenes sp. were found significantly using spearman correlation coefficients (P

Feeding strategy of blue swimming crab (Portunus pelagicus) was investigated monthly in Khuzestan province water from April-2016 to march-2017. Samples were catch by trawl net. The content of P. pelagicus stomachs, percentage of occurrence frequency and Frequency percentage of feeding items was checked. In crab stomachs different feeding items group such as crustacean, mollusks, sponges, phytoplanktons, corals, fish, sand particles and etc. Was observed. The highest frequency of occurrence belonging to sponges, crustaceans and mollusks, respectively. Furthermore, Frequency percentage of sponges (38.65%) was higher than other preys. Costello's graphical model analysis Results analysis of P. pelagicus stomach content by Costello's model showed that this crab is a predator with specific feeding nich and feeding specific prey include sponges, crustacean and mollusks during a year. Though, it's feeding pattern show few seasonally fluctuations. In this model, phytoplanktons, fish, polycheats, corals, nematode, protista, ctenophore, nematodes, cestod, sea insects and sand identified as accidental or rare prey. Probably, ingest by crab while feeding from specific prey.

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.

The importance of the use of medicinal plants against infectious and non-infectious diseases is completely obvious. The replacement of synthetic drugs due to their multiple properties in the prevention and treatment of many diseases, particularly in the aquaculture industry seems to be very important. This study was performed with the aim of assessing the acute toxicity (LC50-96) of thyme essential oil on rainbow trout.
To study the effect of the essential oils, 80 premature rainbow trout with an average weight of 10±0.5 in 9-liter tanks were exposed to different concentrations of essential oils of thyme and daily losses based on OECD protocol were calculated during 96 hours. All the physical and chemical factors such as water temperature, dissolved oxygen, pH, nitrite, nitrate, ammonium levels, electrical conductivity and water hardness were measured in different treatments. The acute toxicity of the essential oil of thyme was calculated using Probit analysis and a concentration of 4.4 ppm was determined.