نشریه پژوهش های علوم و فنون دریایی
سال دوازدهم شماره 2 (تابستان 1396)

Groundwater is the most important source for various uses, including drinking and farming requirements. In Qazvin plain region the existence of these resources such as springs are very important for livelihood and consumption of the region’s population. In this study, fifteen springs were sampled in 2013. The aim of this study was to evaluate water quality of springs in the north region of Qazvin plain for drinking and agricultural purposes. For this purpose, for classification of water quality for drinking water, the Water Quality Index (WQI) method and for agricultural water usages, Wilcox classification, sodium percentage and RSC was used. The results indicated that among springs evaluated, based on the WQI method, about 93 percent of them were categorized in good and excellent range and about 7 percent in poor range. Based on Wilcox classification, about 80 percent of samples were categorized in the range of low salt level suitable for agriculture (C2S1), and 20 percent were categorized as salty and should only be used when necessary(C3S1). The classification based on the percentage of sodium, showed that about 80 percent of the samples examined were in excellent, good and acceptable conditions and 20 percent were in uncertain status. Similarly, according to RSC rankings, about 93 percent had acceptable quality, and 7 percent had poor quality. In general, according to the results of classification of this study area, springs were suitable and favorable for drinking and farming purposes and a few need further monitoring and investigation.

The aim of this study was to evaluate the toxicity effect of Cadmium heavy metal on some serological parameters of Silver carp which have been in the vicinity of cadmium for a short term. In this study a total of 135 fish with mean weight of 50±10grand mean length of 13±1cm were placed in 9 aquariums of 90-liter capacity, in contact with 0.5 and 10 mg/L of CdCl2.Sampling of fishwas done randomly every 12 hours until 96 hours from caudal vein. The results showed that, the level of triglyceride in 24 and 48 hours decreased significantly, but showed no significant increase in 72 hours. The level of cholesterol increased significantly at 72 and 96 hours with increasing the concentration of cadmium (P<0/05). Glucose level increased significantly in 72 hours, but significantly decreased with increasing the concentration of cadmium in 72 and 96 hours (P<0/05). The level of total protein decreased significantly in 24 and 96 hours with increasing the concentration of cadmium, and in 72 hours increased significantly (P<0/05). The level of albumin increased significantly in 96 hours. Based on these results, biochemical parameters are useful for monitoring of cadmium acute toxicity in Silver Carp.

In this study, the amount and type of oil pollution in Pantogammarus maeoticusand sediment of the southern shores of the Caspian Sea in four stations (Sari, Chalus, Anzali, Astara) in June 2015 were investigated. Samples were taken from sediment and Gammarus. and were frozen and delivered to the laboratory. Oil pollution analysis of samples was performed using gas chromatography-mass spectrometry. The amount of hydrocarbons in Gammarus of the Chalus station was significantly different (P<0/05) in comparison with the other three stations. The highest pollution level (10±0.1 ppm) was in Gammarus of Chalus station. There was no significant difference in the hydrocarbon levels of sediments in four stations. To determine the nature and source of contamination, the molar mass of hydrocarbons was investigated. In Astara and Anzali stations the molar mass of hydrocarbons were less than 20 and hence had petrogenic origin. In Sari and Chalus stations the molar mass of hydrocarbons were more than 20 and therefore had indigenous and human origin.

Electronic and electrical wastes are special types of wastes, the main components of which include capacitors, transistors, ICs, electronic circuits, cathode and anode components have toxic and pathogenic properties and are stable in the environment and even in body of animal, are corrosive to installations and equipment The purpose of this study is to investigate and identify the effective factors in the liberation of metals, in particular cadmium, in the surrounding environment. Accordingly, the effect of different factors such as temperature, pH, humic acid and time on the release of cadmium from these wastes to aquatic environments has been studied. For this purpose, the selected parts were analyzed and examined. The results indicate that in the aqueous medium, the amount of cadmium penetration in the very acidic and very alkaline pH, the release rate increases. Also, in the aqueous medium, the increase in temperature increases the penetration of cadmium in the environment, and the effect of the contact time parameter is also proportional to the pH variation.

The fatty acid profile of fresh and dry candy fish of Hypophtalmichthys molitirix were identified and effects of the dry candy on them were investigated. In addition, the shelf life of dry candy of the fish was found in cold conditions (3-4ºC). The profile of fatty acids in fresh and dry candy samples were identified and measured using a GC instrument equipped with a FID detector. The fatty acid content in initial samples for SFA, MUFA and PUFA were 27/5± 0/2, 46/39± 0/5 and 26/11± 0/1 %, respectively. During a 90-day storage, the percentage changes of dry candy samples were, for SFA (27/82± 0/7 to 33/69± 0/84), MUFA (46/77± 0/2 to 46/39± 0/2) and PUFA (26/11± 0/2 to 17/45± 0/2) which were statistically significant (p>0/05). During the 90 days of storage, temperature was about 3-4ºC, the peroxide changed from 3/08± 0/02 to 6/10± 0/02 and reached 5/48 meq O2kg -1. In conclusion, the shelf life of dry candy flesh of this fish in cold conditions was predicted to be one month.

This study was carried out for determining beach seine effects on the macroinvertebrate communities in Shohadaye Anzali -Shirin Mahale andestuaries of Polrud River study areas. In order to survey the effects of beach seine, samplings were carried out in selected stations during the beach seine fishery season (October- March) and when no beach seine fishery was performed (June-September). Hence, four stations in Shohadaye Anzali - Shirin Mahale and three stations in Polrud River estuaries were chosen for sampling. Statistical analysis of data, normalization, correlation, mean comparison for different parameter used, was performed by applying Kolmogorov–Smirnov test (K–S test) and Pearson's Correlation Coefficient, respectively. One-way ANOVA for comparison of means of each parameter, between stations, was used. Classifications of homogeneity of the groups of different benthic organisms throughout the stations were analyzed by Tukey’s test. The results of this study showed that there were significant differences in frequency and biomass of the macroinvertebrate species, during the the beach seine fishery season and after the closing of beach seine fishery (p< 0.05). The results also showed that there were no significant differences in species diversity index (p > 0.05).

Dust storm is one of the most important climate phenomena in the east of Iran. Because the soil type of this area is fine aggregate, the appropriate wind velocity causes to rise of the particles and when the wind speed exceed than the certain threshold, suitable situation for dust and sand storms would provide. In this article to investigate the mentioned phenomenon we analyzed synoptic data from meteorological station in Zabol for the 15-years period from 1995 to 2010. To analyze the dust storm, Horizontal visibility less than 1000 m was defined as the index. Based on this definition, two of the most severe dust storms in spring and summer were chosen and by using the Synoptic data archives NCEP/ NCAR, Synoptic and dynamic conditions of the dust storms were investigated. The results showed that in the summer due to the thermal low pressure system over Pakistan accompanied by cold air advection in the North East of Iran, Causing an Intensive pressure gradient creation in the region and conditions for wind, exceed than the threshold, would be provided. In spring the a baroclinic atmospheric system with low humidity, and Relatively severe cold air advection accompanied by a active cold front, cause increases in wind speed, reducing horizontal visibility and creating dust storms in the east region of Iran.

Underwater pipelines are exposed to hydrodynamic and hydrostatic parameters of the environmental conditions, in the region. In this study, in order to investigate the stability of the underwater pipelines, taking into account the waves and currents induced forces, a stability analysis is performed. There are few standards for designing and analysis of underwater pipelines. The two standards, DNV-RP-C205 and DNV-RP-E305 were used. The study area was the coastal zone of Asaluyeh Port and data used included Asaluyeh wave data, from 2007 to 2008, which were collected by a floating buoy. On the other hand, data on currents were based on Ports and Maritime Organization information. Hydrodynamic coefficients such as Reynolds number, Kvlgan Carpenter and hydrodynamic forces induced on the pipeline in different conditions were calculated. The results showed that in current conditions, designing pipes larger than 0.7m in diameter is not suitable. However, the most suitable designs are pipes with 0.4m in diameter. The minimum weight of pipes with 0.7m diameter, in significant wave height condition under the water, was calculated to be 1365 kg/m.