فصلنامه بوم شناسی آبزیان
سال ششم شماره 1 (پیاپی 601، تابستان 1395)

We conducted a glasshouse experiment as a factorial in randomized study with six replications on pasture species of Schoenoplectus triqueter in Gonbad Kavoos University from 2012-2013. Treatments included height waterlogging in four levels (control, equal to the water surface, 10 cm below the water surface, 20 cm below the water surface) and waterlogging period over three levels (10, 20 and 30 days). In this investigation, we measured the morphological traits (length root, the number of rhizome, length rhizome, the number of internode, dry weight of root, dry weight of rhizome, the number of shoot stems and shoot dry weight) and physiological traits (proline and chlorophyll content). The results showed that the contraction effect of period × height waterlogging was significant in 1% level on all studied traits expect for root volume. We observed increased length and dry weight of root, the number of rhizome, length rhizome, number of internode, and number of shoot stems at a treatment of 10 cm below the water surface in three periods of waterlogging and with an increase of waterlogging period. The highest proline and chlorophyll contents were observed in the control group and the group with 10 cm below the water surface. This species could be introduced to flood resistance.

Changes in the color of sea water caused by algal bloom has continuously risen in recent decades. This increase is due to the harmful effects of human activities that allow sea water to change from a normal to an abnormal state. Satellite sensors are the most accessible, cost-effective means of monitoring. They have been allocated to a large number of marine science studies. The MODIS satellite data that examines changes in color of the sea has been used in this study. In the Persian Gulf and Oman Sea, red tide phenomenon began October 2008 and continued until May 2009 with a high intensity that covered large areas. The results showed that the use of different algorithms and necessary corrections could be achieved in the concentration and size of red tide by color changes of the sea water, marine and oceanic detected by satellite sensors, and extent of changes found.

The current study aims to investigate the community structure of macrobenthos to evaluate water quality of Jajrood River, Northeast Tehran, Iran. We conducted this study in 12 stations during the Spring and Winter seasons of 2014-2015. The sampling method of macrobenthos is use of the surber sampler device with three replications in each station. We measured physical and chemical parameters in each station (temperature, pH, electrical conductivity, BOD, total suspended solids, nitrate, dissolved oxygen, ammonia, and fecal coliform). We used Canonical Correspondence Analysis to examine the effects of the physical-chemical parameters on the population distribution of macrobenthos. According to the results, we identified 11362 of macrobenthos 6 orders and 25 families. The greatest frequency (52/56) of creatures belonged to the order Ephemeroptera, whereas the lowest frequencies (0.07) was seen in the order Coleopteran. Water temperature, ammonia, and electrical conductivity parameters had the largest effect in distribution of macrobenthos. The correlation between biology index and physical and chemical index of IRWQISC showed that margalef, TBI, and IBI indices were the best metrics that assessed water quality. Other than the Abnic and Taletange stations, the water quality in the other stations was unsuitable. We propose that efficient management practices should be implemented to improve water quality of this river.

We examined the temporal trend in mean trophic level (mTL), trophic category landing (TrC) and landing profile (LP) of the exploited marine community (49 species) in the fishing zone of Hormozgan (north of Persian Gulf and Oman Sea) from 2001 to 2011. LP had an increasing trend (r = 0.88, P

This study has been carried out in the coast of Chabahar Bay from March, 2013 to Febuary, 2014. We sampled macrofouling organisms in three stations. Overall, 40 species of macrofouling organisms were detected in which Barnacles, sponges, Bryozoans, echinoderms, Polychaetes and Gastropods were the major groups. The majority of biomass and highest density were observed in the first half of the sequence. Biomass and density differences in the sequence of 6 months on structures was evident. Amphibalanus amphitrite had the highest participation in these sequences.

The effect of macro green algae (Chaetomorpha gracilis) inf Bandar-Abbas and filamentous green algae (Spirogyra sp.) in the Sirch river (Kerman Province) were assayed on growth characteristics of the tomato (Lycopersicum sculentum). In the seed priming experiment, we collected hot water extracts of green algae (Chaetomorpha gracilis) from Bandar Abbas seashores and filamentous green algae (Spirogyra sp.) from Sirch River, Kerman Province. Gold seaweed extract (commercial seaweed extract), distilled water, salicylic acid, ascorbic acid and control were used for the seed germination assay. Mean comparison of seed germination data revealed that Gold seaweed extract showed the highest germination percentage followed by extracts of filamentous green algae (Spirogyra sp.) from the Sirch River and Chaetomorpha gracilis from Bandar Abbas seashores. Primed seed with Chaetomorpha gracilis and Gold seaweed extract had the highest stem and root lengths. In the second experiment, we analyzed the effect of algae extract on growth characteristics of tomato seedlings, treatments of hot water extracts of Chaetomorpha gracilis and filamentous green algae of Sirch, Gold seaweed extract, liquid kelp foliar fertilizer, and distilled water under greenhouse conditions. Extracts of Chaetomorpha gracilis, Gold seaweed and liquid kelp foliar fertilizer had the highest positive effects on root and shoot length, total chlorophyll and leaf width.

In the present study, we evaluated the effects of eyestalk ablation, Ovaprim hormone injected and sterile vehicle solution injected (control) on maturation, Ovarian tissue and biochemical changes in Litopenaeus vannamei. Sterile vehicle solution and hormone injections at 500 and 1000 ng/g body weight were performed with a 100 μl volume in three steps (0, 7 and 14 days). We examined 60 females at 4 treatments for 30 days. The apparent observation and histological studies showed that the highest percentage of the adult females and mature oocytes were related to eyestalk ablation treatment. We analyzed biochemical compounds (protein, lipid and carbohydrates) hemolymph, and body muscles at three stages of sampling (immature, maturation and after spawning). At different stages of sexual devlopment, significant differences in hemolymph and muscle amount of protein were observed between treatments (P

Heavy metals are non-biodegradable and tend to accumulate in tissues of organisms such as fish. Considering the various health risks and the nutritional benefits associated with fish consumption; assessment of heavy metals in fish tissues is important. The present study aims to measure and assess lead and cadmium concentrations in the muscles of Liza saliens from the Gomishan International Wetland. We collected 23 Liza saliens samples from 9 stations in different locations. The muscle samples were prepared by acid digestion (HNO3 and HCLO4) for analysis by graphite furnace atomic absorption spectroscopy (GFAAS). Mean concentration of cadmium was 163.26 ± 35.82 and lead was 12.46 ±8.62 μg/g dry weight. No significant correlation existed between lead and cadmium concentrations with body weight. The highest concentrations of these metals were detected in stations of the west and center of wetland that seemed to be caused by the transfer of pollutants from the Caspian Sea to the wetland. The concentration of cadmium and lead were lower than the standard levels suggested by WHO, FAO, UK (MAFF) and NHMRC. Currently, no risk to human health from the consumption of fish tissue was not determined. Therefore, consumption of Grey Mullet does not have any risk to human health.

Heavy metals are pollutants from multiple man-made or natural sources which directly or indirectly enter bodies of water. Therefore, investigation of deposits as metal contaminants is important. The international wetlands of Tiyab and Kolahi are among the most important ecosystems in the south of Iran that due to development programs are polluted by different sources. In order to identify environmental pollution of heavy metals in the sediment of Tiyab and Kolahi, we have collected 22 surface sediment samples from 11 study sites using the Grap Sampler. In order to determine the toxicity and limit pollution index of elements in the sediment, we used the Sediment Quality Standard of America and the Canadian Sediment Quality Standard was used. The results showed that the concentration of heavy metals had the following average ppm: cadmium (6.15), lead (23.22), nickel (142.8) and copper (36.18). The accumulation index of Muller regarding the level of contamination of the area in question indicated that the pollution level of the wetlands was at a medium level. Due to the concentration of heavy metals and the index findings, it could be concluded that cadmium contamination could be related to oil and anthropogenic pollution.

Iodine is the main ingredient produced by the thyroid hormone, which playa a central role in the metabolism and the immune system. The present study aims to evaluate the effects of feeding Artemia fransiscana enriched with potassium iodide on antioxidant and immune gene expression in zebra fish (Danio rerio). Zebra larvae with an average weight of 2±0.01 mg were randomly distributed into 4 treatments with 3 replicates. The treatments were larvae fed 0.2, 0.5 and 1 mg/L potassium iodide enriched Artemia for 2 months. Result showed that potassium iodide significantly (P≤0.05) increased antioxidant and immune gene expression in zebra fish and the intensity of changes followed a dose- dependent manner. The 1 mg/L potassium iodide treated fish showed the highest gene expression in all studied genes. Due to changes in the expression of immune and antioxidant related genes, it appeared that potassium iodide could improve immune and antioxidant function in zebrafish.

This study aimed to determine the effects of replacement fish meal by different levels of gammarus meal on growth performance and body composition of juvenile Siberian sturgeon (Acipenser baerii). We distributed 245 Siberian sturgeon juveniles (initial body weight: 14.24±0.15 g) in five treatments and three replications. The experimental diets were replaced by 10%, 20%, 30%, and 40% gammarus meal. During the 9-week feeding period, the fish were fed with the experimental diets to apparent satiation four times daily. According to the results, there were no significant differences in the protein and fat efficiency ratios, visceral index and survival rate (P>0.05). The fish that received 10% and 20% treatments had a significantly greater mean final weight, weight gain, feed conversion ratio, body weight increase, final length, condition factor, specific growth rate, food intake and hepatosomatic index compared with the other treatments (P0.05). The results of this study indicated that a diet with 20% gammarus meal could be used in Siberian sturgeon feed.

In this study, we investigated the effects of different levels of dietary nucleotide (0, 0.2, 0.4 and 0.6%) on immunity parameters and total protein plasma of Litopenaeus vannamei female brood stock in four experimental treatments (three replication per treatment) during the maturation period and after eye stalk ablation. Total soluble proteins and immunity parameters such as total haemocyte count and differential haemocyte counts were measured in three phases of the experimental period - the start of feeding, 21 (pre-eyestalk ablation period) and 30 (9 days post-eye stalk ablation) days after the start of feeding. The results showed that total haemocyte count and differential haemocyte count in samples from dietary nucleotide treatments significantly differed (P

In this study, we investigated the effects of herbal supplements of Carum carvi and Trigonella foenum graecum on soluble protein and antibacterial activity of mucus in common carp (Cyprinus carpio) fingerlings. Fish with a mean weight of 2.457±0.057 g were divided randomly into 7 treatments (one control group and the experimental groups treated with diets that contained different percents of caraway and fenugreek (0.5, 1 and 1.5%) with 3 replicates and a density of 15 fish per replicate. After 8 weeks feeding, the epidermal mucus protein level and antimicrobial activity against two gram-negative bacteria (Escherichia coli and Seratia marcescens) were measured. Results showed that protein levels of mucus significantly increased in fish fed diets that contained 1% herbal supplements compared to the control and other treatments (P>0.05). In addition, we observed significant differences in antibacterial activity of mucus in fish fed with caraway and fenugreek compared with the control group (p

The purpose of this study was to evaluate the effects of zinc oxide nanoparticles and ions on intestinal tissue histopathology of freshwater crayfish (Astacus leptodactylus) under laboratory conditions. We evaluated two concentrations of zinc oxide nanoparticles and zinc ions (0.5 µm/l and 1.0 mg/l) with a control group. After 14 days of exposure to the nanoparticles of zinc oxide and zinc ions, we obtained intestinal tissue samples from the crayfish. We observed damages such as increased goblet cells and degeneration of the epithelium, edema, increased plasma cells and lymphocytes, and necrosis in the intestines of freshwater crayfish.

In this study, we evaluated the effects of treated effluent of Khuzestan Pars Paper Industry (0.5% and 1%) on liver biochemical factors of Alburnus mossulensis during 21 days. There were significantly increased aspartate aminotransferase, lactate dehydrogenase and creatine phosphokinase levels observed in fish after a 21-day exposure to treated effluent. Alanine aminotransferase, alkaline phosphatase and total protein significantly decreased in liver tissue after exposure to effluent of Khuzestan Pars Paper Industry (P